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Sample records for alkaline pluton kola

  1. Martian alkaline basites chemically resemble basic rocks of the Lovozero alkaline massif, Kola peninsula

    Science.gov (United States)

    Kochemasov, G.

    " (syenite, granite) for Mars [5]. Actually the martian missions successively discovered andesite, dacite, low-Fe highlands. Now "Spirit" has found on a small outlier of highlands -Columbia Hills -a batch of thinly layered gently dipping light rocks that surely are not impact melts as at very short distance there is a sharp transition from light Fe-poor to ultrabasic rocks (on opposite slopes of this small hill) [6]. This layered sequence of more or less altered and weathered rocks resembles differentiated sequences of Lovozero and other alkaline and UB-alkaline massifs of Kola Peninsula (though fresh and much richer in alkalis). Here we compare compositions of alkaline basic rocks of Columbia Hills (dyke or sill [4]) with that of basic volcanics and a later dyke at Lovozero. 5 analyses in wt.%: 1-Backstay (tra1 chybasalt) & 2-Irvine (basalt) of CH, 3-augiteporphyrite, 4-essexite-porphyrite, 5- alkali- lamprophyre dyke of Lovozero. SiO2 -49.9, 47.7, 45.78, 48.09, 41.57; TiO2 - 0.93, 1.07, 7.80, 2.35, 2.92; Al2 O3 -13.2; 10.8, 8.08; 13.74; 11.77; Fe2 O3 -3.40, 7.79 (4.99), 5.90, 6.00, 4.53; FeO -10.6, 12.5 (15.0), 8.65, 7.60, 8.28; MnO -0.25, 0.37, 0.12, 0.17, 0.28; MgO -8.36, 10.8, 7.61, 7.19, 10.59; CaO -6.09, 6.12, 10.73, 8.77, 11.24; Na2 O -4.02, 2.72, 2.80, 2.84, 3.63; K2 O -1.02, 0.69, 1.97, 2.09, 1.38. Compositional similarities between basites occurring in alkaline conditions on both planets can be found. References: [1] Kochemasov G.G. (1999) Theorems of wave planetary tectonics // Geophys. Res. Abstr., v. 1, # 3, 700; [2] Gellert R. et al. (2006) JGR Planets, v. 111, #E2, EO2505; [3] Squyres S.W. et al. (2006) JGR Planets, v.111, #E2, EO2511; [4] McSween H.Y. et al. (2006) JGR Planets, submitted ; [5] Kochemasov G. G. (1995) Golombek M.P., Edgett K.S., Rice J.W. Jr. (Eds). Mars Pathfinder Landing Site Workshop II: Characteristics of the Ares Vallis Region and Field trips to the Channeled Scabland, Washington. LPI Tech. Rpt. 95-01. Pt.1.LPI, Houston, 1995, 63 pp.; [6

  2. Thermobarometry of mantle-derived garnets and pyroxenes of Kola region (NW Russia: lithosphere composition, thermal regime and diamond prospectivity

    Directory of Open Access Journals (Sweden)

    Dmitry R. Zozulya

    2009-12-01

    Full Text Available More than 700 pyrope, chrome diopside and chromite grains recovered from Quaternary sediments of the Kola craton, and from the Ermakovsky kimberlite in the Terskii Coast field were analyzed in order to determine their P-T parameters. Ni-thermometry on pyropes from SE Kola gives a range of temperatures between 650–1250 °C, corresponding to a sampling interval of c. 75–190 km. Pyrope compositions imply a stratified structure to the SE Kola lithospheric mantle, with G10-pyropes absent in the shallow mantle (75–110 km where the bulk of the G9-pyropes are sourced, while a deeper mantle horizon, between110 and 190 km, has contributed abundant G10-pyropes. Approximately 16 % of all these pyropes are derived from the diamond stability field. The Ni-temperatures of garnets from the Ermakovsky kimberlite reveal a relatively shallow sampling interval of the mantle (c.75–140 km, dominantly within the graphite-stability field. P-T values for peridotitic chrome diopsides imply that most grains from SE Kola were derived from the graphite stability field, apparently originating from non-diamondiferous alkaline-ultramafic dykes. Nevertheless, c. 15 % of SE Kola diopsides have been derived from the stability field of diamond. Diopsides from SW Kola mostly plot in the diamond stability field. 20 % of diopsides from central Kolaare derived from the diamond stability field, whereas diopsides from northern Kola region all fall within the stability field of graphite. The maximum depth of diopside xenocryst sampling varies from up to 200 km in SE and SW Kola, to 170 km in central Kola, and only to 140 km in the northern Kola region. The P-T values for chrome diopsides imply significant regional differences in heat flow: 38–44 mW/m^2 within the southern part of Kola adjacent to the Kandalaksha graben; 35–38 mW/m^2 towards the SE and SW away from the graben; 38–44 mW/m^2 in central Kola; and up to 50 mW/m^2 in northernmost Kola. These data indicate that

  3. High-K calc-alkaline magmatism at the Archaean-Proterozoic boundary: implications for mantle metasomatism and continental crust petrogenesis. Example of the Bulai pluton (Central Limpopo Belt, South Africa)

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    Laurent, Oscar; Martin, Hervé; Doucelance, Régis; Moyen, Jean-François; Paquette, Jean-Louis

    2010-05-01

    The Neoarchaean Bulai pluton, intrusive within the supracrustal granulites of the Central Limpopo Belt (Limpopo Province, South Africa) is made up of large volumes of porphyritic granodiorites with subordinate enclaves and dykes which have monzodioritic and charno-enderbitic compositions. New U-Pb LA-ICP-MS dating on separated zircons yielded pluton emplacement ages ranging between 2.60 and 2.63 Ga, which are slightly older than previous proposed ages (~ 2.57-2.61 Ga). The whole-rock major- and trace-element composition of the Bulai pluton evidences unequivocal affinities with "high-Ti" late-Archaean sanukitoids. It belongs to a high-K calc-alkaline differentiation suite, with metaluminous affinities (0.7 affinities, such as eNd ranging between -0.5 and 0.5, and in addition, are very rich in all incompatible trace elements, which is particularly obvious in monzodioritic enclaves and enderbites where primitive mantle-normalized LILE and LREE contents are up to 300. These characteristics point to an enriched mantle source for the Bulai batholith. Chondrite normalized, REE patterns are strongly fractionated ([La/Yb]N ~ 25-80), mainly due to high LREE contents (LaN ~ 250-630), and chiefly high HFSE contents (Nb ~ 15-45 ppm ; up to 770 ppm Zr) indicate that the metasomatic agent is a silicic melt rather than a hydrous fluid. Moreover, based on high Nb/Ta, Th/Rb, La/Rb and low Sr/Nd and Ba/La, we suggest that the metasomatic agent is a granitic melt generated by melting of terrigenous sediments. Interactions of this melt with mantle peridotites implies that sediments are located under a mantle slice; geometry which is easily achieved in subduction zone settings. This conclusion is supported by the fact that Bulai trace element patterns are very similar to those of sub-actual potassic magmas generated in magmatic arc environments by interactions between mantle and terrigenous sediments (e.g. Sunda arc). Geochemical modeling indicates that the mafic facies of the Bulai

  4. PRECIPITATION OF PLUTONOUS PEROXIDE

    Science.gov (United States)

    Barrick, J.G.; Manion, J.P.

    1961-08-15

    A precipitation process for recovering plutonium values contained in an aqueous solution is described. In the process for precipitating plutonium as plutonous peroxide, hydroxylamine or hydrazine is added to the plutoniumcontaining solution prior to the addition of peroxide to precipitate plutonium. The addition of hydroxylamine or hydrazine increases the amount of plutonium precipitated as plutonous peroxide. (AEC)

  5. Nutritional and Phytochemical Screening of Garcinia kola

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    A.O. Adesuyi

    2012-02-01

    Full Text Available The Nutritional and Phytochemical Screening of Garcinia kola were Investigated. The Nutritional Analyses involves Proximate analyses; Anti-Nutrient composition and Mineral composition. The Phytochemical parameters carried out were Flavonoids; Phenol; Alkaloids; Saponin and Tannin. The proximate Analyses showed that the sample has high level of Carbohydrate 88.30%, little amount of Crude Fibre and Protein 1.23 and 1.86%, respectively and negligible amount of Ash content 0.47% and Crude Fat 0.19%. Also a considerable level 7.6% of moisture was shown. This composition shows that the sample could be a good source of Carbohydrate, dietary fibre and Protein. The Anti-Nutrient composition presents are in negligible amount. The Parameters are Oxalate (0.423 g/100 g, Phytate (0.57 g/100 g and Trypsin Inhibitor (0.37 g/100 g. The Mineral content show a high level of calcium (2200 ppm,Potassium (968 ppm and Sodium (852 ppm. Other mineral analysed were found to range from moderate to negligible. Garcinia Kola could be a good source of minerals despite the negligible amount of Anti-Nutrients found that could prevent the absorption of these minerals. The result also show a high level of Saponin (2.471%, Flavonoids (2.041% and Cardiac Glycosides (3.421%. Alkaloids and Tannins were present in Considerable amount 0.647 and 0.34%, respectively. But Phenol is present in negligible amount (0.147%. With the high level of Cardiac glycosides, Garcinia kola can be used as anti-inflammatory and as active components of drugs derived from plants.

  6. Possibilities for wind energy on the Kola peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, J.; Rathmann, O.; Lundsager, P. [and others

    1999-03-01

    This paper presents an extensive feasibility study regarding the introduction of wind energy in the energy supply of the Kola peninsula in north-western Russia that was carried out during 1996-97. The study covers as well grid connected wind turbines as autonomous systems and a wind atlas was prepared. Special emphasis is put on non-technical activities and objectives like financing models, international funding and a sound politic support. The wind resources on the Kola peninsula are excellent and there are still no reasons to why wind energy installations couldn`t be carried out successfully. Recommendations for starting this development are presented. (au)

  7. Mesoarchean Gabbroanorthosite Magmatism of the Kola Region

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    Kudryashov, N.; Mokrushin, A.

    2012-04-01

    The Kola peninsula is the region marked with development of anorthosite magmatism in the NE Baltic Shield. The Archaean gabbroanorthosites intrusions - Tsaginsky, Achinsky and Medvezhe-Schucheozersky - have the age of 2.7-2.6 Ga (Bayanova, 2004). The Patchemvarek and Severny gabbroanorthosites intrusions are located in the junction zone of the Kolmozero-Voronja greenstone belt and the Murmansk domain. Age data for sedimentaryvolcanogenic rocks of the Kolmozero-Voronja belt and Murmansk domain granitoids are 2.8-2.7 Ga. The gabbroanorthosites intrusions have more calcic composition (70-85% An) of normative plagioclase, and low contents of TiO2, FeO, and Fe2O3. In terms of chemical composition, the gabbroanorthosites of the studied massifs are close to the rocks of the Fiskenesset Complex (Greenland) and to the anorthosites of the Vermillion Lake Complex (Canada). U-Pb zircon dating established Mesoarchean ages of 29257 and 29358 Ma for the gabbroanorthosites of the Patchemvarek and Severny massifs, respectively. It was shown that the gabbroanorthosites of the studied massifs have fairly low REE contents (Cen = 2.2-4.2, Ybn = 1.6-2.6) and distinct positive Eu anomaly. Comagmatic ultrabasic differentiates have practically unfractionated REE pattern, low total REE contents (Cen = 1.2, Ybn = 1.1, La/Ybn = 1.32), and no Eu anomaly. The studied samples of the Archean gabbroanorthosites are characterized by positive "Nd= + 2.68 for the gabbroanorthosites of the Severny Massif and from + 2.77 to + 1.66 for the Patchemvarek Massif. The rocks of the Severny and Patchemvarek massifs has 87Sr/86Sri = 0.702048 and 87Sr/86Sri = 0.70258_8, respectively. The oldest U-Pb zircon ages for the gabbroanorthosites of the Patchemvarek and Severny massifs marking the Mesoarchean stage in the evolution of region. The differences in the initial 143Nd/144Nd ratios between the Neoarchean and the Mesoarchean gabbroanorthosites suggest the existence of two mantle sources. One of them produced

  8. Petrology of some Mexican mesozoic-cenozoic plutons: Sources and tectonic environments

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    Stein, G.; Lapierre, H.; Monod, O.; Zimmermann, J.-L.; Vidal, R.

    1994-01-01

    In central and southern Mexico, three Late Mesozoic to Early Tertiary plutonic suites have been investigated. They record the evolution of the Mexican Pacific margin through space and time and more specifically its crustal thickness. In Central Mexico the La Angostura pluton (110-100 Ma) is calc-alkaline and intrudes a Late Jurassic-Early Cretaceous exotic arc, represented by the Guanajuato magmatic sequence. Both pluton and country rocks were affected by a greenschist facies metamorphism. Their high ɛNd(i) and low ɛSr(i) values are more or less similar to those of the Guanajuato arc tholeiitic rocks and suggest that both the calc-alkaline intrusions and the arc tholeiitic suite were derived from a mantle source essentially uncontaminated by a crustal component. The La Angostura calc-alkaline plutonic rocks could represent the remnants of the mature stage of this arc before its tectonic emplacement on the western margin of the North American craton. In the vicinity of the La Angostura pluton, the Eocene (ɛ50 Ma) Comanja and La Estancia granodiorites are chemically similar to volcanic arc granites and their low ɛNd(i) and high ɛSr(i) ratios suggest that they were derived from a mantle source highly contaminated by continental crust. Finally, the youngest plutonic suite (38 Ma), exposed near Zihuatanejo ranges from gabbro to granodiorite and displays calc-alkaline compositional features. Their ɛNd(i) and ɛSr(i) ratios indicate that the Zihuatanejo plutonic suite was derived from a mantle source which has been weakly contaminated by subducted sediments and/or continental crust. The contrasting petrology, chemistry and isotopic ratios of the Comanja-La Estancia granodiorites and the Zihuatanejo gabbro-granodiorite suite reflect a difference in thickness of their continental basement.

  9. Late-stage sinking of plutons

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    Glazner, A.F.; Miller, D.M.

    1997-01-01

    Many granodiorite to diorite plutons in the Great Basin of western North America are surrounded by rim monoclines or anticlines that suggest relative downward movement of the plutons while wall rocks were hot and ductile. We propose that such plutons rise to a level of approximately neutral buoyancy and then founder as their densities increase ??? 40% during crystallization. Late-stage sinking of intermediate to mafic plutons should be common when wall rocks are rich in weak, low-density minerals such as quartz and calcite. Structures related to sinking will overprint those related to initial pluton emplacement and may be mistaken for regional tectonic structures.

  10. Potential use ofGarcinia kola as hop substitute in lager beer brewing.

    Science.gov (United States)

    Aniche, G N; Uwakwe, G U

    1990-09-01

    The chemical, brewing and anti-microbial properties of a tropical seed,Garcinia kola, were compared with traditional hops. Treatment ofGarcinia kola with methanolic lead acetate produced a yellow precipitate from which organic acids (alpha acids) were contirmed to be present by thin-layer chromatography. Hops, however, had a higher concentration of organic acids thanGarcinia kola. Laboratory brewing trials withGarcinia kola and hops gave beers with simillar chemical properties. Organoleptically,Garcinia kola beer was as acceptable to tasters as hopped beer except that it had an improved bitterness.Garcinia kola and hop extracts exerted similar anti-microbial effects on two beer spollage micro-organisms (Lactobacillus delbruckii andCandida vini).

  11. Marketingový mix firmy ALU KOLA CB

    OpenAIRE

    URBAN, Karel

    2011-01-01

    This bachelor thesis is focused on a marketing mix practical application in my own company ALU KOLA CB. My company sells alloy wheels and tyres for personal cars. In a literary review are introduced and explained terms marketing, marketing mix and its parts - product, price, place and promotion. In a practical part of this thesis are these terms applied on my company. The end of this part contains results and improvement suggestions.

  12. Definition of magmatic suites in ediacaran bodies of the NE Province Borborema (State of Rio Grande do Norte: Pitombeira, Taipu and Gameleira Plutons

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    Maria Tatiany Duarte de Oliveira

    2014-12-01

    Full Text Available The Pitombeira, Taipu and Gameleira plutons, located in the northeasternmost portion of the São José do Campestre Domain within the Borborema Province (NE, Brazil, are subjects of lithogeochemical studies in the present work. The Pitombeira Pluton comprises a monzo- to syenogranitic facies defined by K-feldspar phenocrysts, and a quartz-dioritic to tonalitic facies, mainly as enclaves, with laths of plagioclase showing compositional zoning and chilled rims. The Taipu Pluton is made of equigranular, locally porphyritic, monzo- to syenogranites, whereas the Gamaleira Pluton encompasses tonalitic and grano- dioritic rocks with porphyritic textures and compositionally zoned plagioclase crystals. Geochemical discriminant diagrams reveal that the rocks forming the Gameleira Pluton are metaluminous, with a calc-alkaline signature and magnesian character, contrasting with the subalkaline (high-K calc-alkaline signature and ferroan character of the Taipu and Pitombeira Plutons, where the former is highly peraluminous and the latter is metaluminous to slightly peraluminous. Rare Earth Elements patterns are similar to all plutons and register negative Eu anomalies and a relative enrichment of LREE over HREE, with LaN/YbN ratios between 9.38 to 16.20 (Gamaleira Pluton, 17.99 to 31.39 (granitic facies of the Pitombeira Pluton, 14.15 to 21.81 (dioritic facies of the Pitombeira Pluton and 15.17 to 175.41 (Taipu Pluton. Based on the combined investigation of structural, textural and geochemical data, a late- to post-collisional tectonic environment is suggested for the plutons here studied.

  13. A comparative study of two rear-arc plutons and implications for the Fuegian Andes tectonic evolution: Mount Kranck Pluton and Jeu-Jepén Monzonite, Argentina

    Science.gov (United States)

    González-Guillot, M.; Prezzi, C.; Acevedo, R. D.; Escayola, M.

    2012-10-01

    A petrologic, geochemical and geophysical study of two Late Cretaceous plutons of the Fuegian Andes is carried out: the Jeu-Jepén Monzonite (JJM) and the Mt. Kranck Pluton (MKP). The plutons show a wide lithological spectrum from ultramafic lithologies (clinopyroxenites and hornblendites), gabbros, diorites to late stage K-feldspar syenite veins. They represent the top of magmatic chambers exposed at or close to the roof level. Mode and chemistry indicate a monzonitic-mildly alkaline trend with high K2O content, equivalent to shoshonitic series. Trace element composition is typical of arc magmas. These features plus their high LILE content (Ba 320-1600 ppm, Sr 475-1560 ppm), high LILE/HFSE ratio (Rb/Zr 0.6-1.6) and age confirm they belong to a rear-arc, monzonitic to mildly alkaline suite (the Fuegian Potassic Magmatism). Therefore, they represent the farthest-from-the-trench plutons in the suite. The petrographical and chemical characteristics of the plutons suggest the lithological spectrum is the result of magmatic differentiation. The process involved crystal accumulation and magma mingling at the early stages, favored either by injections of fresh magma from deeper reservoirs and/or the action of convective currents within the chamber. Country rock assimilation also took part simultaneously with crystallization. The JJM and MKP lie along the trace of a Cenozoic left-lateral strike-slip fault (Magallanes-Fagnano fault system), on opposite blocks. However, lithological, chemical and geophysical subtle differences between these two plutons suggest they evolved in individual magmatic chambers and therefore the distance between them cannot be used as an estimation of total offset along the fault, as was indicated in previous studies.

  14. A refinement of the emission data for Kola Peninsula based on inverse dispersion modelling

    NARCIS (Netherlands)

    Prank, M.; Sofiev, M.; Denier Van Der Gon, H.A.C.; Kaasik, M.; Ruuskanen, T.M.; Kukkonen, J.

    2010-01-01

    The study reviews the emission estimates of sulphur oxides (SOx) and primary particulate matter (PM) from the major industrial sources of Kola Peninsula. Analysis of the disagreements between the existing emission inventories for the Kola region combined with forward and inverse ensemble dispersion

  15. Genesis of felsic plutonic magmas and their igneous enclaves

    DEFF Research Database (Denmark)

    Clemens, John D.; Maas, Roland; Waight, Tod Earle

    2016-01-01

    -type Pyalong pluton was emplaced, apparently along an east-west-orientated fracture zone. Around 367 Ma, the main I-type Baynton pluton intruded as numerous shallow-dipping sheets. The last plutonic event was the intrusion of the broad, thin, flat-lying, and crosscutting sheet of the I-type Beauvallet pluton...

  16. Apatite fission track thermochronology of Khibina Massif (Kola Peninsula, Russia): Implications for post-Devonian Tectonics of the NE Fennoscandia

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    Veselovskiy, Roman V.; Thomson, Stuart N.; Arzamastsev, Andrey A.; Zakharov, Vladimir S.

    2015-12-01

    The thermal history of the Kola Peninsula area of NE Fennoscandia remains almost fully unknown because of the absence of any thermochronological data such as apatite and/or zircon fission track or (Usbnd Th)/He ages. In order to fill this gap and to constrain the post-Devonian erosion and exhumation history of this region, we present the results of apatite fission track (AFT) dating of eleven samples selected from the cores taken from different depths of the northern part of the Khibina intrusive massif. The Rbsbnd Sr isochron age of this alkaline magmatic complex which is located at the center of Kola Peninsula is 368 + 6 Ma (Kramm and Kogarko, 1994). Samples were analyzed from depths between + 520 and - 950 m and yielded AFT ages between 290 and 268 Ma with an age uncertainty (1σ) of between ± 19 Ma (7%) and ± 42 Ma (15%). Mean track lengths (MTL) lie between 12.5 and 14.4 μm. Inverse time-temperature modeling was conducted on the age and track length data from seven samples of the Khibina massif. Thermal histories that best predict the measured data from three samples with the most reliable data show three stages: (1) 290-250 Ma-rapid cooling from > 110 °C to 70 °C/50 °C for lower/upper sample correspondingly; (2) 250-50 Ma-a stable temperature stage; (3) 50-0 Ma-slightly increased cooling rates down to modern temperatures. We propose that the first cooling stage is related to late-Hercynian orogenesis; the second cooling stage may be associated with tectonics accompanying with opening of Arctic oceanic basin. The obtained data show that geothermal gradient at the center of Kola Peninsula has remained close to the modern value of 20 °C/km for at least the last 250 Myr. AFT data show that the Khibina massif has been exhumed not more then 5-6 km in the last 290 Myr.

  17. Dichotomy of The Messada Pluton, Serbo-Macedonian Massif, Greece: From Rifting to Subduction

    Science.gov (United States)

    Vasilatos, Charalampos

    2016-10-01

    The Messada pluton is a mafic intrusion that is located about 12 km SW of Serres town, (Macedonia Greece) that intrudes the two mica, biotite and the augen gneisses of the Vertiskos formation (Serbo-Macedonian massif). The aim of this study is to investigate, define and evaluate the geochemical characteristics of the pluton in order to determine the geotectonic environment in which the parental magma has been formed. The Mesada pluton is a mid to coarse grained intrusion presenting petrographic variety from diorite and quartz diorite to tonalite and granodiorite. The variety in petrography reflects its chemical inhomogeneity in major and trace elements. It is suggested that parts of pluton have been formed by distinctly different types of magmas originated in diverse geotectonic settings. Those parts of quartz diorite and tonalite composition, present similar geochemical characteristics, LILE/HFSE ratios and negative Nb, but no Ti anomalies in their primitive mantle normalized trace elements spider grams. They exhibit higher HFS values than those of granodioritic composition. Moreover, their ORG normalized spider grams not only suggest that they have been evolved by a common parental magma, but also present the typical characteristics of a “crust dominated” within plate pluton that may have been formed in an early stage during rifting, prior to a subsequent subduction episode. This interpretation may be in accordance with the suggestion for the Gondwanian origin of the more silicic Triassic rift related meta-granites (e.g. Arnea plutonic complex) of the Serbo-Macedonian massif. In contrary; the parts of Mesada pluton of granodioritic composition, exhibit a calc-alkaline to high K calc-alkaline magmatic suite and present higher LILE/HFSE and LREE/HREE ratios, related to a higher crustal component contribution for the magma genesis. Furthermore, their primitive mantle normalized spider grams’ present negative anomalies at Nb and Ti. These characteristics

  18. Zircon LA-ICPMS study and petrogenesis simulation of Dahuabei pluton in the Wulashan area,Inner Mongolia

    Institute of Scientific and Technical Information of China (English)

    Dapeng Li; Yuelong Chen; Liemeng Chen; Zhong Wang; Jinbao Liu

    2009-01-01

    Dahuabei pluton in the Wulashan area,Inner Mongolia,is an alkaline and peraluminous granitic pluton.LA-ICPMS U-Pb dating of zircons indicates that this pluton crystallized at 330±10 Myr.The pluton did not experience apparent zircon fractionation.The consistent temperatures between Zr saturation (765℃) and the average zircon-rutile Ti equilibrium (780℃),together with zircon ages and their CL images,indicated that there were no inherited zircons in this pluton.Through the simulation of the dry-system crystallization process of magma cooling at 200 MPa and 1100-709℃,the phase diagram and composition evolution tendency of different phases were obtained.The magma reached its liquidus at 1069℃.Sanidine was the first crystallized phase;at 709℃ the residual magma was less than 4%,and the range of 1069-719℃ should be the most suitable approach to the real condition.It is shown that at least some part of the pluton underwent such isobaric equilibrium crystallization processes during its crystallization.

  19. MEASUREMENTS OF THE CONFINEMENT LEAKTIGHTNESS AT THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

    Energy Technology Data Exchange (ETDEWEB)

    GREENE,G.A.; GUPPY,J.G.

    1998-08-01

    This is the final report on the INSP project entitled, ``Kola Confinement Leaktightness'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.1. This project was initiated in February 1993 to assist the Russians to reduce risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Units 1 and 2, through upgrades in the confinement performance to reduce the uncontrolled leakage rate. The major technical objective of this-project was to improve the leaktightness of the Kola NPP VVER confinement boundaries, through the application of a variety of sealants to penetrations, doors and hatches, seams and surfaces, to the extent that current technology permitted. A related objective was the transfer, through training of Russian staff, of the materials application procedures to the staff of the Kola NPP. This project was part of an overall approach to minimizing uncontrolled releases from the Kola NPP VVER440/230s in the event of a serious accident, and to thereby significantly mitigate the consequences of such an accident. The US provided materials, application technology, and applications equipment for application of sealant materials, surface coatings, potting materials and gaskets, to improve the confinement leaktightness of the Kola VVER-440/23Os. The US provided for training of Russian personnel in the applications technology.

  20. Distinctly different parental magmas for plutons and lavas in the central Aleutian arc

    Science.gov (United States)

    Cai, Y.; Rioux, M. E.; Kelemen, P. B.; Goldstein, S. L.; Bolge, L.; Kylander-Clark, A. R.

    2014-12-01

    While it is generally agreed that continental crust is generated by arc magmatism, average arc lavas are basaltic while the bulk continental crust is andesitic, and this has led to many models for secondary reprocessing of the arc crust in order to form continental crust. We report new data on calc-alkaline plutons in the central Aleutians showing that they have distinctly different sources compared to Holocene tholeiitic lavas. Therefore the lavas are not representative of the net magmatic transfer from the mantle into the arc crust. Eocene to Miocene (9-39 Ma) intermediate to felsic plutonic rocks from the central Aleutian arc show higher SiO2 at a given Mg#, higher ɛNd- and ɛHf-values, and lower Pb isotope ratios than Holocene volcanic rocks from the same region. Instead, the plutonic rocks resemble volcanics from the western Aleutians isotopically, and have chemical compositions similar to bulk continental crust. These data could reflect temporal variation of Aleutian magma source compositions, from Eocene-Miocene "isotopically depleted" and predominantly calc-alkaline to Holocene "isotopically enriched" and predominantly tholeiitic. Alternatively, they may reflect different transport and emplacement processes for the magmas that form plutons and lavas: calc-alkaline magmas with higher Si content and high viscosity may preferentially form plutons, perhaps after extensive mid-crustal degassing of initially high water contents. The latter case implies that the upper and middle arc crust is more like the calc-alkaline bulk composition of the continental crust than the lavas alone. Crustal reprocessing mechanisms that preserve upper and middle arc crust, while removing lower arc crust, can account for the genesis and evolution of continental crust. Since gabbroic lower arc crust extends from ca 20-40 km depth, and is density stable over most of this depth range, "delamination" of dense lithologies [1] may not be sufficient to accomplish this. Alternatively

  1. The Fazenda Gavião granodiorite and associated potassic plutons as evidence for Palaeoproterozoic arc-continent collision in the Rio Itapicuru greenstone belt, Brazil

    Science.gov (United States)

    Costa, Felipe G.; Oliveira, Elson P.; McNaughton, Neal J.

    2011-08-01

    Several granitic plutons have intruded the Palaeoproterozoic Rio Itapicuru greenstone belt, São Francisco craton, Brazil, in the time interval 2163-2080 Ma, but their tectonic significance is poorly understood. The Fazenda Gavião granodiorite (FGG) is one of a set of plutons emplaced along the western boundary of the greenstone belt with Archaean migmatite-gneiss basement. The pluton is mostly composed of hornblende granodiorite, occasionally crosscut by syn-plutonic mafic dykes. The FGG is metaluminous, medium- to high-K calc-alkaline with relatively constant silica abundances (SiO2 ˜ 63-66 wt%), high Sr (900-800 ppm) and high Ba (1000-1500 ppm). The associated mafic dykes are ultrapotassic, with high abundances of Ba, Sr, MgO, Ni, Cr, and light rare earth elements, suggesting derivation from partial melts of an enriched mantle source. The FGG originated probably by fractional crystallization from a primitive K-rich mafic magma that interacted with crustal melts. Its zircon U-Pb SHRIMP age of 2106 ± 6 Ma indicates that the FGG is younger than the early (2163-2127 Ma) tonalite-trondhjemite-granodiorite (TTG) and calc-alkaline arc plutons of the greenstone belt, and is closely related in time and space with potassic to ultrapotassic plutons (ca. 2110-2105 Ma). The negative ɛNd(t) of FGG and coeval K-rich plutons of the Rio Itapicuru greenstone belt contrasts markedly with the positive ɛNd(t) of the older arc plutons, indicating a major change of isotope signatures in granites of the Rio Itapicuru greenstone belt with time. This isotope shift may be related to magma contamination with older continental material and/or derivation of the parental potassic magma from enriched lithospheric mantle sources. We suggest that the K-rich plutons were emplaced during or shortly after Palaeoproterozoic arc-continent collision.

  2. Origin of adakite-like plutons in southern Korea

    Science.gov (United States)

    Oh, Jeong-Im; Choi, Sung Hi; Yi, Keewook

    2016-10-01

    We present Sr-Nd-Pb isotopic compositions for two adakite-like intrusions in southern Korea (Jindong and Bongnae), including major and trace element concentrations, and the sensitive high-resolution ion microprobe (SHRIMP) zircon U-Pb age. Our aim is to constrain the origin and tectonomagmatic processes that gave rise to the plutons. A SHRIMP U-Pb zircon age of 88.7 ± 0.7 Ma was obtained from a Jindong granodiorite sample. The Jindong plutons belong to the medium-K calc-alkaline series, and have an overall enrichment in large ion lithophile elements (LILE), such as K, Rb, Ba, and Pb, and a relative depletion in high field strength elements, such as Nb, Ta, and Ti, compared with the neighboring elements in the primitive mantle-normalized multi-trace element variation diagram. It was found that (87Sr/86Sr)i = 0.70475-0.70596, (143Nd/144Nd)i = 0.512547-0.512604, [(εNd)i = + 0.4 to 2.2], and (206Pb/204Pb)i = 18.19-18.37, which fall within the field of the arc-type Cretaceous to Tertiary Bulguksa intrusive rocks in the Sr-Nd and Pb-Pb isotopic correlation diagrams. The elevated Sr/Y (17-40), but low La/Yb (3.7-8.8) ratios of the Jindong plutons, together with their coherent geochemical trends and U-shaped rare earth element (REE) patterns, indicate that they were not formed by slab melting, but by amphibole-dominated fractional crystallization of the Bulguksa-like arc magma. A SHRIMP U-Pb zircon age of 226.5 ± 2.5 Ma was obtained from a Bongnae tonalite sample. The Bongnae plutons belong to the shoshonitic series. Their trace element patterns resemble the Jindong samples, but are characterized by significantly negative U anomalies in mafic rocks. They also have elevated MgO, Ni, Co, Cr, Rb, Ba, Sr, and low Al2O3 and Na2O contents at a given SiO2 concentration compared with the Jindong plutons, and are typified by highly radiogenic Sr and unradiogenic Nd and Pb isotopic compositions: [(87Sr/86Sr)i = 0.71096-0.71290, (143Nd/144Nd)i = 0.511641-0.511681, (εNd)i = - 13

  3. Kola Nut and Conflict Resolution Among the Igala People of Kogi State, Nigeria

    Directory of Open Access Journals (Sweden)

    Joel Abah

    2016-04-01

    Full Text Available This paper examined Kola nut and Conflict Resolution among the Igala people of Kogi State, Nigeria. In a world ravaged by conflicts, certain Africans have kept the fire of brotherhood, through the breaking and eating of Kola nut. Literatures exist on Conflict Resolution, but no empirical study on the topic in question. The aims are to examine (a the types of Kola nut cotyledons and its relevance in conflict resolution (b the myths about Kola nut that enhances conflict resolution, and (c its role in conflict resolution. The qualitative approach was adopted. The sources of data were primary and secondary. The Primary Sources included 20 oral interviews. Purposive sampling was adopted. Content analysis was used to analyse. The secondary sources included books and an unpublished work. The findings reveal (a two types of Kola nut, (cola acuminata 0-7 cotyledons and cola nitida 2 cotyledons, (b As regards the myth, it is used to invite and welcome the ancestors during conflict resolution, whosoever harbours grudges against a neighbour after the kola had been eaten will come under the wrath of the ancestors, and (c It is the harbinger of peace. In conclusion, peace can only be guaranteed when there is security and justice, which could be embedded in a unifying factor(s, like the kola nut. Any community that finds this generally acceptable factor will experience a considerable level of peace, especially when acculturated into every aspect of the modern conflict resolution mechanisms, putting into consideration the indigenous socio-religious conflict resolution strategies.

  4. Petrology and radiogeology of the Stripa pluton

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, H.; Flexser, S.; Andersson, L.

    1980-12-01

    Both the quartz monzonite and the metavolcanic leptite which it intruded are strongly fractured. Two stages of fracture filling are evident; an earlier stage encompassing quartz, sericite, feldspar, epidote, and chlorite, and a later stage dominated by carbonate minerals. The Stripa quartz monozite is chemically and mineralogically distinct from other plutons in the region. Muscovite is the predominant mica in the quartz monzonite; biotite has been altered to chlorite, hornblende is absent, and accessory minerals are scarce. In contrast, in other plutons in the Stripa region, biotite and hornblende are prominent mafic minerals and accessory minerals are abundant. The Stripa quartz monzonite is also considerably more radioactive than the the leptite and other plutons in the region. Uranium and thorium abundances are both approx. 30 ppM, considerably higher than in normal granitic rocks where the thorium-to-uranium ratio generally exceeds 2. Potassium-argon dating of muscovite from the Stripa quartz monzonite indicates that this rock may be older, at 1691 million years than granitic rock of the neighboring Gusselby and Kloten massifs, whose ages, based on K-Ar dating of biotite, are respectively 1604 and 1640 m.y. Heat flow and heat productivity considerations show that although Stripa quartz monzonite contains high abundances of radioelements, the pluton has little efect on the regional heat flow. If it occurs in a layered plutonic setting, it is not more than 1.5 km thick; otherwise it may comprise a stock, dike, or border phase that is relatively small compared with the large granitic plutons exposed in the region.

  5. Thermal evolution of plutons: a parameterized approach.

    Science.gov (United States)

    Spera, F

    1980-01-18

    A conservation-of-energy equation has been derived for the spatially averaged magma temperature in a spherical pluton undergoing simultaneous crystallization and both internal (magma) and external (hydrothermal fluid) thermal convection. The model accounts for the dependence of magma viscosity on crystallinity, temperature, and bulk composition; it includes latent heat effects and the effects of different initial water concentrations in the melt and quantitatively considers the role that large volumes of circulatory hydrothermal fluids play in dissipating heat. The nonlinear ordinary differential equation describing these processes has been solved for a variety of magma compositions, initial termperatures, initial crystallinities, volume ratios of hydrothermal fluid to magma, and pluton sizes. These calculations are graphically summarized in plots of the average magma temperature versus time after emplacement. Solidification times, defined as the time necessary for magma to cool from the initial emplacement temperature to the solidus temperature vary as R(1,3), where R is the pluton radius. The solidification time of a pluton with a radius of 1 kilometer is 5 x 10(4) years; for an otherwise identical pluton with a radius of 10 kilometers, the solidification time is approximately 10(6) years. The water content has a marked effect on the solidification time. A granodiorite pluton with a radius of 5 kilometers and either 0.5 or 4 percent (by weight) water cools in 3.3 x 10(5) or 5 x 10(4) years, respectively. Convection solidification times are usually but not always less than conduction cooling times.

  6. Bullialdus - Strengthening the case for lunar plutons

    Science.gov (United States)

    Pieters, Carle M.

    1991-01-01

    Although many craters expose materials of a composition different from that of the local surroundings, Bullialdus has excavated material representing three distinct stratigraphic zones that occur in the upper 6 km of crust, the top two of which are gabbroic and the deepest of which is noritic. This three-component stratigraphy at Bullialdus provides strong evidence that the lunar crust includes pockets of compositionally layered material reminiscent of mafic layered plutons. When combined with previous information on the compositional diversity at other large craters, these remote analyses obtained in a geologic context substantially strengthen the hypothesis suggested from lunar samples that plutons play an integral role in lunar crustal evolution.

  7. Multiphase groundwater flow near cooling plutons

    Science.gov (United States)

    Hayba, D.O.; Ingebritsen, S.E.

    1997-01-01

    We investigate groundwater flow near cooling plutons with a computer program that can model multiphase flow, temperatures up to 1200??C, thermal pressurization, and temperature-dependent rock properties. A series of experiments examines the effects of host-rock permeability, size and depth of pluton emplacement, single versus multiple intrusions, the influence of a caprock, and the impact of topographically driven groundwater flow. We also reproduce and evaluate some of the pioneering numerical experiments on flow around plutons. Host-rock permeability is the principal factor influencing fluid circulation and heat transfer in hydrothermal systems. The hottest and most steam-rich systems develop where permeability is of the order of 10-15 m2. Temperatures and life spans of systems decrease with increasing permeability. Conduction-dominated systems, in which permeabilities are ???10-16m2, persist longer but exhibit relatively modest increases in near-surface temperatures relative to ambient conditions. Pluton size, emplacement depth, and initial thermal conditions have less influence on hydrothermal circulation patterns but affect the extent of boiling and duration of hydrothermal systems. Topographically driven groundwater flow can significantly alter hydrothermal circulation; however, a low-permeability caprock effectively decouples the topographically and density-driven systems and stabilizes the mixing interface between them thereby defining a likely ore-forming environment.

  8. Safety Evaluation of Aqueous Extract of Garcinia Kola Seeds in Male Wistar Rats

    Directory of Open Access Journals (Sweden)

    Musa Toyin Yakubu

    2015-11-01

    Full Text Available Background: Garcinia kola seed is consumed indiscriminately in Nigeria without recourse to its potential toxicity. Therefore, this study was aimed at assessing the toxicity of the aqueous extract of G. kola seeds on selected tissues of male rats. Methods: Thirty male rats (215.00 ± 18.58 g were assigned into four groups: A, B, C and D which received 0.5 ml of distilled water, 25, 50 and 100 mg/kg body weight of the extract respectively, once daily for 7 days. Biochemical indices of organ damage and toxicity were determined using standard methods. Results: The extract significantly (P0.05 altered. Conclusion: The treatment related alterations in the present study indicates that the aqueous extract of G. kola seeds at the doses of 25, 50 and 100 mg/kg body weight caused functional toxicity to the organs of the animals and thus not safe as an oral remedy.

  9. Petrology and radiogeology of the Stripa pluton

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, Harold; Flexser, Steve; Andersson, Lennart

    1980-12-01

    To better define the character of the rock encompassing the thermomechanical and hydrological experiments at the Stripa mine in central Sweden, and to help determine the size of the Stripa pluton, detailed studies were conducted of the petrology and radiogeology of the quartz monzonite and adjacent rocks. Petrologic studies emphasized optical petrography, with supplementary X-ray diffraction, X-ray fluorescence and microprobe analyses. Radiogeologic investigations were based primarily on surface and underground gamma-ray spectrometric measurements of uranium, thorium and potassium, supplemented by laboratory gamma spectrometric analyses and fission-track radiographic determinations of the locations and abundance of uranium in the rock matrix. Both the quartz monzonite and the metavolcanic leptite which it intruded are strongly fractured. Two stages of fracture filling are evident; an earlier stage encompassing quartz, sericite, feldspar, epidote, and chlorite, and a later stage dominated by carbonate minerals. The Stripa quartz monzonite is chemically and mineralogically distinct from other plutons in the region. Muscovite is the predominant mica in the quartz monzonite; biotite has been altered to chlorite, hornblende is absent, and accessory minerals are scarce. In contrast, in other plutons in the Stripa region biotite and hornblende are prominent mafic minerals and accessory minerals are abundant. The Stripa quartz monzonite is also considerably more radioactive than the leptite and other plutons in the region. Uranium and thorium abundances are both- 30 ppm, considerably higher than in "normal" granitic rocks where the thorium-to-uranium ratio generally exceeds 2. Potassium-argon dating of muscovite from the Stripa quartz monzonite indicates that this rock may be older, at 1691 million years than granitic rock of the neighboring Gusselby and Kloten massifs, whose ages, based on K-Ar dating of biotite, are respectively 1604 and 1640 m.y. Heat flow and heat

  10. Feasibility study on introduction of KOLAS (Korea Laboratory Accreditation Scheme) in nuclear examination facility

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dae Gyu; Hong, K. P.; Song, W. S.; Min, D. K

    1999-07-01

    To be an institute officially authorized by the KOLAS, the understanding and the analysis of following contents is required.: the understanding of concept required to get the accreditation of testing, the system specifying an internationally accredited testing and examination organization, international organization in the field of laboratory accreditation, domestic laboratory accreditation organization(KOLAS), the investigation of the regulations with laboratory accreditation in Korea, the investigation of the procedures accrediting a testing and examination organization, the investigation of general requirements(ISO 17025) for a testing and examination organization. (author)

  11. Digital relief 3D model of the Khibiny massive (Kola peninsula)

    Science.gov (United States)

    Chesalova, Elena; Asavin, Alex

    2015-04-01

    On the basis of maps of 1: 50,000 and 1: 200,000 3D model Khibiny massif developed. We used software ARC / INFO v10.2 ESRI. This project will be organised to build background for gas pollution monitoring network. We planned to use the model to estimate local heterogeneities in the composition of the atmosphere at the emanation of greenhouse gases in the area, the construction of models of vertical distribution of the content of trace gases in the rock mass. In addition to the project GIS digital elevation model contains layers of geological and tectonic map that allows us to estimate the area of the output of certain petrographic rock groups characterized by different ratios of emitted hydrocarbons (CH4/ H2). The model allows to construct a classification of fault in the array. At first glance, there are two groups of faults - the ancient associated with the formation of the intrusive phases sequence, and the young - due to recent tectonic shifts. Ancient faults form a common semicircular structure of the pluton cause overall asymmetry Khibin heights with the transition to the border area between the Khibiny and Lovoozero. Modern tectonics mainly represented by radial and chord faults which are formed narrow mountain valleys and troughs. It remains an open question as to which system fault (old or young) is more productive to gas emanations? On the one hand the system characterized by a large old depth, on the other hand a young more active faults. Address these issues require further detailed observations. The essential question is to assess the possibility of maintaining a constant concentration gradient of these impurities in the atmosphere due to gas emanations of fracture zones and areas enriched occluded gases. In the simulation of these processes can be used initially set parameters: 1 the flow rate of the gas impurities 2 the value of wind flows in closed and open valley 3 Assessment of thermal diffusion coefficients determined by the temperature gradient

  12. [An in vitro study of the action of kola nitida on bacterial strains implicated in dental caries and periodontal diseases].

    Science.gov (United States)

    Kamagate, A; Attoli, L; Kone, D; Ly, Bakayoko; Brou, E; Sixou, M

    2002-06-01

    The Nitida Kola is a substance extracted from the kolanut. In West Africa its use by chewing is widespread among the Manding people. It's said to have tonic, stimulant and aphrodisiac characteristics and even recent studies have shown that it has antibacterial characteristics. The aim of this study is to make an estimation of the Nitida Kola's effects on different bacterial species involved in the two main oral and dental pathologies (teeth decays and periodontal illnesses). The obtained results indicate that the kola extract is not effectual against the tried-out bacteria at regular dose used by chewing.

  13. Correct nomenclature for the Angadimogar pluton, Kerala, southwestern India

    Indian Academy of Sciences (India)

    H M Rajesh

    2006-04-01

    The proper usage of modal composition and geochemical classification of granitoids is discussed for assigning a proper nomenclature for the Angadimogar pluton,Kerala,southwestern India.This discussion is mainly aimed at addressing questions concerning the nomenclature of Angadimogar pluton (syenite vs. granite).Modal composition and whole-rock XRD data clearly show that the pluton exposed near Angadimogar is a quartz-syenite and its geochemistry is typical of a ferroan, metaluminous,alkali (A-type)granitoid.

  14. The Precambrian/Lower Cambrian pluton from Vila Nova (Central Portugal)

    Energy Technology Data Exchange (ETDEWEB)

    Reis, A. I. M.; Silva, M. M. V. G.; Antunes, I. M. H. R.

    2010-07-01

    The Vila Nova pluton is a small, Pre-Variscan granitic body that intruded rocks of the Central Iberian Zone near the contact with the Ossa Morena Zone and is affected by several shear zones and faults. Its contact metamorphic aureole is constituted by micaschist with porphyroblasts in the outer zone and hornfels in the inner zone. Small mainstreamed xenoliths are dispersed all over the body. The pluton has a great mineralogical heterogeneity with pronounced variations in muscovite/biotite and plagioclase/ microcline contents and is classified as granite, granodiorite or tonalite. It is a leuco granite, highly peraluminous (A/CN K = 1.31 - 1.64), magnesian and calc-alkaline to alkaline-calcic. The variation diagrams show curvilinear trends with silica. Eu/Eu* = 0.47 - 0.77 and there is a slight enrichment in LREE relative to HREE. The normalized diagrams indicated dominantly crustal granite, related to subduction. U-Pb isotopic data of zircon and monazite gives 540-542 Ma age. (Author) 19 refs.

  15. Infrasound research at Kola Regional Seismological Centre, Russia

    Science.gov (United States)

    Asming, Vladimir; Kremenetskaya, Elena

    2013-04-01

    A small-aperture infrasound array has been installed in Kola Peninsula, Russia 17 km far from the town of Apatity in the year 2000. It comprises 3 Chaparral V microbarographs placed closely to the APA seismic array sensors and equipped with pipe wind reducing filters. The data are digitized at the array site and transmitted in real time to a processing center in Apatity. To search for infrasound events (arrivals of coherent signals) a beamforming-style detector has been developed. Now it works in near real time. We analyzed the detecting statistics for different frequency bands. Most man-made events are detected in 1-5 Hz band, microbaromes are typically detected in 0.2-1 Hz band. In lower frequencies we record mostly a wind noise. A data base of samples of infrasound signals of different natures has been collected. It contains recordings of microbaromes, industrial and military explosions, airplane shock waves, infrasound of airplanes, thunders, rocket launches and reentries, bolides etc. The most distant signals we have detected are associated with Kursk Magnetic Anomaly explosions (1700 km far from Apatity). We implemented an algorithm for association of infrasound signals and preliminary location of infrasound events by several arrays. It was tested with Apatity data together with data of Sweden - Finnish infrasound network operated by the Institute of Space Physics in Umea (Sweden). By agreement with NORSAR we have a real-time access to the data of Norwegian experimental infrasound installation situated in Karasjok (North Norway). Currently our detection and location programs work both with Apatity and Norwegian data. The results are available in Internet. Finnish militaries routinely destroy out-of-date weapon in autumns at the same compact site in North Finland. This is a great source of repeating infrasound signals of the same magnitude and origin. We recorded several hundreds of such explosions. The signals have been used for testing our location routines

  16. Electromagnetic sounding of the Kola Peninsula with a powerful extremely low frequency source

    Science.gov (United States)

    Velikhov, E. P.; Grigoriev, V. F.; Zhdanov, M. S.; Korotayev, S. M.; Kruglyakov, M. S.; Orekhova, D. A.; Popova, I. V.; Tereschenko, E. D.; Schors, Y. G.

    2011-05-01

    Experiment on electromagnetic sounding of the Kola Peninsula using unique mobile measuring complex of the low-frequency sounding was conducted, allowing to investigate a geoelectric section with a depth of several kilometers on distances up to 100 km from the stationary transmitting aerial. Excess on the order of amplitudes of the vertical component above the horizontal at all frequencies of sounding was registered in a number of points of measurements. This feature managed to be explained quantitatively by circulation of current on regional faults with the closure of current through the sea—before unknown galvanic coastal effect. Interpretation of the results of modeling and neural network solving of inverse problem essentially specifies the fault tectonics of the central part of the Kola Peninsula. Anomaly remote from the observation profile was found out—local pinch of a crustal conductive layer consisting of graphitized rocks and associated with the zone of overthrust.

  17. Dynamics of biomass and population density of fucus algae of the Kola Bay, Barents Sea

    Directory of Open Access Journals (Sweden)

    Malavenda S. S.

    2016-03-01

    Full Text Available The long-term dynamics of biomass and population density of Fucus distichus and F. vesiculosus in the southern and middle knees of the Kola Bay have been analyzed. The feedbacks between these parameters and their changes over several years have been revealed for the first time. Changing the prevalence of biomass and population density can be considered as an adaptation at the population level to maintain the stability of algae communities in chronic pollution

  18. Producers’ motivation for collective action for kola production and marketing in Cameroon

    Directory of Open Access Journals (Sweden)

    Steven Franzel

    2012-04-01

    Full Text Available Collective action has been used as a strategy to improve the benefits of smallholder producers of kola nuts in Cameroon. Despite demonstrated benefits, not all producers are involved in the collective action. The presented study used a modified Technology Acceptance Model (TAM namely the Collective Action Behaviour model (CAB model to analyse kola producers’ motivation for collective action activities. Five hypotheses are formulated and tested using data obtained from 185 farmers who are involved in kola production and marketing in theWestern highlands of Cameroon. Results which were generated using Partial Least Squares (PLS approach for Structural Equation Modelling (SEM showed that farmers’ intrinsic motivators and ease of use influenced their behavioural intent to join a group marketing activities. The perceived usefulness that was mainly related to the economic benefits of group activities did not influence farmers’ behavioural intent. It is therefore concluded that extension messages and promotional activities targeting collective action need to emphasise the perceived ease of use of involvement and social benefits associated with group activities in order to increase farmers’ participation.

  19. Site-sensitive hazards of potential airborne radioactive release from sources on the Kola peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, R.; Thaning, L. [Defence Research Establishment, Umeaa (Sweden). Div. of NBC Defence; Baklanov, A. [Russian Science Academy, Apatity (Russian Federation). Kola Science Centre

    1998-02-01

    In this work we focus on cases of airborne releases from some of the sources on the Kola Peninsula - primarily nuclear reactors on submarines and the Kola Nuclear Power Plant (KNPP). The purpose of our study is to illustrate, and discuss some features - dependent on site and release characteristics - of the deposition patterns resulting from assumed unit radioactive releases to the atmosphere from a location at a fjord and from the KNPP in Polyarnye Zori. Using meteorological data for one real weather situation, the analysis is based on simulating the transport in air of assumed radioactive releases and estimating the deposition pattern on local, meso- and regional scales. By allowing unit releases to occur simultaneously from the site at the fjord and from the power plant (and with the same release profile in time) comparisons are made of differences in deposition patterns in and outside the Kola region. In this case study a set of assumed release heights, durations of the release, and particle size distributions are applied to indicate the dependence for the resulting deposition pattern on these parameters

  20. Reconstruction of early Holocene paleoclimate and environment in the SW Kola region, Russian Arctic

    Science.gov (United States)

    Grekov, Ivan; Kolka, Vasiliy; Syrykh, Liudmila; Nazarova, Larisa

    2016-04-01

    In the current period of the global climate change it becomes necessary to have a clear understanding of not only the changes taking place in the components of the natural environment, but also to understand development of all interactions between those components. Quaternary terrigenic sediments and lakes of the Kola Peninsula store information about the development of the region in the Late Glacial and Holocene: movements of the glacier, neotectonic activity, post-glacial rebound, formation and development of natural environments after deglaciation. Multi-proxy study of landscapes evolution of the Kola Peninsula in the Late Quaternary will help to establish a detailed reconstruction of climatic and environmental changes of this poor studied sector of the Arctic. Quaternary history on the Kola Peninsula is represented mainly by Late Pleistocene and Holocene sediments covering the Baltic Shield (Lavrova, 1960; Evzerov, 2015). Several palaeolimnological investigations in the Baltic Shield area have been performed earlier (Donner et al., 1977; Anundsen, 1985; Berglund, 2004). Studies of the southern coast of the Kola Peninsula have shown that marine transgression took place in the Late Pleistocene that was then replaced by a regression with variable speed. The slowdown of the uplift of the area took place between 8800 - 6800 BP (cal. years) and corresponded to the time of the Tapes transgression of the Arctic Ocean (Evzerov et al. 2010; Kolka, et al., 2013). Palaeoclimatic studies based on micro-paleontological analyzes indicate uneven development of the Kola Peninsula landscapes in the Late Glacial and Early Holocene. The northern coast of the Peninsula became free of ice first. In this area tundra-steppe vegetation was established for a short time and was later replaced by tundra (Snyder et al, 2000). Southern part of the Kola Peninsula was dependent on the conditions of deglaciation of the White Sea basin and cleared of ice much later (Evzerov et al., 2010; Kolka

  1. Intrusive rocks and plutonic belts of southeastern Alaska, U.S.A.

    Science.gov (United States)

    Brew, David A.; Morrell, Robert P.; Roddick, J.A.

    1983-01-01

    About 30 percent of the 175,000-km2 area of southeastern Alaska is underlain by intrusive igneous rocks. Compilation of available information on the distribution, composition, and ages of these rocks indicates the presence of six major and six minor plutonic belts. From west to east, the major belts are: the Fairweather-Baranof belt of early to mid-Tertiary granodiorite; the Muir-Chichagof belt of mid-Cretaceous tonalite and granodiorite; the Admiralty-Revillagigedo belt of porphyritic granodiorite, quartz diorite, and diorite of probable Cretaceous age; the Klukwan-Duke belt of concentrically zoned or Alaskan-type ultramafic-mafic plutons of mid-Cretaceous age within the Admiralty-Revillagigedo belt; the Coast Plutonic Complex sill belt of tonalite of unknown, but perhaps mid-Cretaceous, age; and the Coast Plutonic Complex belt I of early to mid-Tertiary granodiorite and quartz monzonite. The minor belts are distributed as follows: the Glacier Bay belt of Cretaceous and(or) Tertiary granodiorite, tonalite, and quartz diorite lies within the Fair-weather-Baranof belt; layered gabbro complexes of inferred mid-Tertiary age lie within and are probably related to the Fairweather-Baranof belt; the Chilkat-Chichagof belt of Jurassic granodiorite and tonalite lies within the Muir-Chichagof belt; the Sitkoh Bay alkaline, the Kendrick Bay pyroxenite to quartz monzonite, and the Annette and Cape Fox trondhjemite plutons, all interpreted to be of Ordovician(?) age, together form the crude southern southeastern Alaska belt within the Muir-Chichagof belt; the Kuiu-Etolin mid-Tertiary belt of volcanic and plutonic rocks extends from the Muir-Chichagof belt eastward into the Admiralty-Revillagigedo belt; and the Behm Canal belt of mid- to late Tertiary granite lies within and next to Coast Plutonic Complex belt II. In addition, scattered mafic-ultramafic bodies occur within the Fairweather-Baranof, Muir-Chichagof, and Coast Plutonic Complex belts I and II. Palinspastic

  2. The chemical and isotopic differentiation of an epizonal magma body: Organ Needle pluton, New Mexico

    Science.gov (United States)

    Verplanck, P.L.; Farmer, G.L.; McCurry, M.; Mertzman, S.A.

    1999-01-01

    Major and trace element, and Nd and Sr isotopic compositions of whole rocks and mineral separates from the Oligocene, alkaline Organ Needle pluton (ONP), southern New Mexico, constrain models for the differentiation of the magma body parental to this compositionally zoned and layered epizonal intrusive body. The data reveal that the pluton is rimmed by lower ??(Nd) (~-5) and higher 87Sr/86Sr (~0.7085) syenitic rocks than those in its interior (??(Nd) ~ 2, 87Sr/86Sr ~0.7060) and that the bulk compositions of the marginal rocks become more felsic with decreasing structural depth. At the deepest exposed levels of the pluton, the ??(Nd)~-5 lithology is a compositionally heterogeneous inequigranular syenite. Modal, compositional and isotopic data from separates of rare earth element (REE)-bearing major and accesory mineral phases (hornblende, titanite, apatite, zircon) demonstrate that this decoupling of trace and major elements in the inequigranular syenite results from accumulation of light REE (LREE)-bearing minerals that were evidently separated from silicic magmas as the latter rose along the sides of the magma chamber. Chemical and isotopic data for microgranular mafic enclaves, as well as for restite xenoliths of Precambrian granite wall rock, indicate that the isotopic distinction between the marginal and interior facies of the ONP probably reflects assimilation of the wall rock by ??(Nd) ~-2 mafic magmas near the base of the magma system. Fractional crystallization and crystal liquid separation of the crystally contaminated magma at the base and along the margins of the chamber generated the highly silicic magmas that ultimately pooled at the chamber top.

  3. Petrogenesis of the Neoproterozoic Ngondo Plutonic complex (Cameroon, west central Africa): a case of late-collisional ferro-potassic magmatism

    Science.gov (United States)

    Tagne-Kamga, Gabriel

    2003-04-01

    The Ngondo complex is a late-collisional pluton, which was emplaced around 600 Ma along a N030° E strike-slip shear zone in the southwestern part of the Neoproterozoic Fold Belt of Cameroon. It comprises three successively emplaced plutonic groups of rocks: (i) mafic to felsic intrusive rocks (MFR), (ii) fine-grained granites (FGG) and (iii) coarse-grained granites (CGG). Late aplitic and pegmatite dykes were emplaced along brittle fractures in these plutons. The complex is metaluminous to weakly peraluminous, high-K, calc-alkaline to " trans-alkaline" ferro-potassic, with mineralogical and geochemical characteristic of I-type granites. The plutonic rocks are characterised by high Ba, Sr, Rb and ∑REE concentrations and low Ni and Cr contents in the mafic members. They also display chondrite-normalised REE patterns characterised by variable LREE enrichment, moderate to minor HREE fractionation with moderate to pronounced negative Eu anomalies (Eu/Eu∗: 0.6-0.9 (MFR), 0.2-0.5 (FGG), 0.3-0.7 (CGG)). Trace element distribution patterns for the three plutonic groups are similar with a distinctive depletion in Nb, Sr and Ti relative to other trace elements and a greater enrichment in LILE compared to HFSE. These plutonic groups present distinct evolutionary trends precluding their origin from differentiation of a single parental magma. The geochemical and isotopic data indicate that they derived from partial melting of heterogeneous (meta)-igneous mafic lower crustal materials, having possibly the composition of amphibolitised high-K calc-alkaline basaltic andesites and andesitic metagreywackes. Petrographic evidences such as the presence of quartz-ocelli, xenocrysts of feldspar, fragments of country rocks (migmatitic gneisses) strongly indicate that crustal contamination may have played an important role in the genesis of the plutonic rocks. This contamination process is further supported by the variation of major and trace elements together with Sr-Nd isotopic data

  4. Nutrient and phytochemical composition of two varieties of Monkey kola (Cola parchycarpa and Cola lepidota): An underutilised fruit.

    Science.gov (United States)

    Ene-Obong, Henrietta N; Okudu, Helen O; Asumugha, Ukamaka V

    2016-02-15

    The nutrient and phytochemical composition of two varieties of Monkey kola: Cola parchycarpa and Cola lepidota were determined. The pulps were extracted, grated and dried using solar dryer. Dried pulps were milled into flour with attrition milling machine (0.5mm sieve size). The nutrient compositions were determined using standard AOAC methods. Gravimetric and spectrophotometric methods were used for phytochemical determinations. There were significant (p1.0 and ⩽0.06, respectively). Monkey kola had substantial amounts of iron, zinc, and copper; the B-vitamins and vitamin C. The phytochemical contents were quiet high, the most abundant being flavonoids (415-494mg/100g). Monkey kola is a fruit that should be fully exploited for its potential health benefits.

  5. Experience of the chronological correlation of the Holocene sea coastal landforms in the Tuloma River valley and the Kola Bay

    Directory of Open Access Journals (Sweden)

    Tolstobrov D. S.

    2016-03-01

    Full Text Available The paper is a continuation of studies of the Earth's crust neotectonic movements within the north-western part of the Kola region. New radiocarbon data of the lake bottom sediments in the Tuloma River valley allowed to modify diagram of the relative uplift lines of the Earth surface in the north-western part of the Kola region and to compare them with previously constructed epeirogenic spectra of coastal landforms for the study area. The dynamics and nature of the area uplift have been established and the dating of the ancient shorelines within the Tuloma River valley and the Kola Bay of the Barents Sea during the Holocene has been carried out

  6. Therapeutic potential of Garcinia kola with reference to the restoration of inhibited acetylcholinesterase activities in induced Clarias gariepinus

    Directory of Open Access Journals (Sweden)

    T.O. Ikpesu

    2014-12-01

    Full Text Available This study was conducted to assess the antidotal prospect of Garcinia kola seeds extract in restoring the activity of inhibited Acetylcholinesterase. This was done by inducing Clarias gariepinus with the enzyme inhibitor (glyphosate pesticide formulation. The fish divided into six groups were exposed different treatments; the pesticide alone, the G. kola seed extract alone and different mixture of the pesticide and G. kola seeds extract. AChE activities in the brain, liver and serum of the fish were measured in the experimental and control fish on day −7, 14, 21 and 28th by the colorimetric method. The enzyme was significantly (p < 0.05 inhibited in the glyphosate formulation test alone and in group IV treatment (0.16 mg/L glyphosate formulation with 150 mg/L of extract. The inhibition percentages of AChE ranged for the brain, liver and serum between 40.7–59.4%, 50–57% and 27.5–51.3%, respectively. The AChE activities were however, recovered in G. kola seeds extract treated aquaria, and were dose, time dependent and organ specific. Modifications of this enzyme may leads to increased perspiration, increased salivation, tearing, blurred vision, abdominal cramping, diarrhea, and if severe enough, death from respiratory depression. This investigation had revealed the therapeutic significance of G. kola seeds extract, by stabilizing the enzyme activity in the investigated fish. Further investigation is required to measure the concentrations of acetylcholine at cholinergic synaptic junction in fish and mammals induced with ant-cholinesterase agent and the possibility of its restoration using G. kola seeds.

  7. Orogenic potassic mafic magmatism, a product of alkaline-peraluminous mixing ? Variscan 'calc-alkaline' rocks from the Central Iberian and Ossa Morena Zones, Central Spain.

    Science.gov (United States)

    Scarrow, Jane H.; Cambeses, Aitor; Bea, Fernando; Montero, Pilar; Molina, José F.; Moreno, Juan Antonio

    2013-04-01

    Orogenic magmatic rocks provide information about mantle and crust melt-generation and -interaction processes. In this context, minor potassic mafic stocks which are formed of enriched mantle and crustal components and are common as late-orogenic intrusions in granitic plutons give insight into the timing of new crust formation and crustal recycling. Potassic mafic stocks are prevalent, albeit low volume, constituents of granite batholiths all through the European Variscan (350-280 Ma). In the Central Iberia Zone, Spanish Central System, crustal-melt, S-type, granitoid plutons are intruded by minor concomitant ultramafic-intermediate appinitic-vaugneritic stocks. Notwithstanding their whole-rock calc-alkaline composition, the stocks apparently did not have a subduction-related origin. Recent studies have attributed their genesis to mixing of alkaline mantle and peraluminous crustal melts. Their primary alkaline character, as indicated by amphibole and biotite mineral chemistry data, points, rather, towards an extension-related genesis. In the Ossa Morena Zone, south of the Central Iberian Zone, the igneous rocks also have a whole-rock calc-alkaline composition which has been considered to be the result of northward subduction of the South Portuguese Zone. Nevertheless, identification of a 'sill' of significant volume of mafic magma in the middle crust, the ´IBERSEIS reflective body', in a seismic profile across the Ossa Morena and South Portuguese Zones has cast doubt upon the calc-alkaline magmatism-subduction model; leading, instead, to the magmatism being attributed to intra-orogenic extension related to a mantle plume active from 340 Ma to 330 Ma. The aim here, then, is to reinvestigate the petrogenesis and age of the calc-alkaline rocks of the Ossa Morena Zone to determine their tectonomagmatic context be it subduction-, plume- or extension-related, and establish what they may reveal about mantle-crust interactions. Focussing, initially, on the Valencia del

  8. Comprehensive paleoseismic geological studies in a key site in southwestern Kola Peninsula (Northeast of the Fennoscandian Shield)

    Science.gov (United States)

    Nikolaeva, S. B.; Nikonov, A. A.; Shvarev, S. V.; Rodkin, M. V.

    2016-07-01

    This paper considers the results of detailed paleoseismic and geological investigations in a key site in the wall of the Imandra Lake depression (Kola Peninsula Region, Northeast of the Fennoscandian Shield). Study of different groups of paleoseismic deformations developed in the fault zone and the application of new methods and techniques made it possible to identify a large seismotectonic zone characterized by great earthquakes at the end of the Late Glacial and in the Holocene. The investigation data are indicative of the necessity to estimate the seismic potential in the Kola Atomic plant area in a different way.

  9. The Early Paleozoic Tectonic Evolution of the West Kunlun Mountains: New Constraint from the North Kiida Pluton

    Institute of Scientific and Technical Information of China (English)

    袁超; 周辉; 孙敏; 李继亮; 侯泉林

    2001-01-01

    Systematic geochemical studies have been conducted on the North Küda Pluton,Pluton is a potassium-rich (K2O>5.4wt%) I-type granitic pluton and does not contain any alkaline ferromagnesian mineral. Its relatively high REE, LILE (e. g. Rb, Cs, U and Th) and HFSE (e. g. Nb, Zr) contents make it very akin to the A-type granites. Its heterogeneous Sr (87Sr/86Sri= 0. 7049~0. 7098) and Nd (εNdT = - 1.05~ - 4.04) isotope compositions preclude the possibility of a pure sedimentary or igneous source. Instead, its geochemical compositions suggest that it may be derived from partial melting of a complex source, which consists of igneous and sedimentary rocks. Its intraplate characteristics, together with coeval mafic dykes,indicate an extensional environment at the end of Caledonian. The recognition of the extensional event does not support a continuous subduction-accretion model for the Paleozoic tectonic evolution of the West Kunlun Mountains. On the contrary, it provides new evidence for the twostage island-arc model.

  10. The Early Paleozoic Tectonic Evolution of the West Kunlun Mountains:New Constraint from the North Kueda Pluton

    Institute of Scientific and Technical Information of China (English)

    袁超; 周辉; 等

    2001-01-01

    Systematic geochemical studies have been conducted on the North Kueda Pluton,West Kunlun,in order to reveal its petrogenesis and tectonic implications.The North Kueda Pluton is a potassium-rich(K2O>5.4wt%)I-type granitic pluton and does not contain any alkaline ferromagnesian mineral.Its relatively high REE,LILE(e.g.Rb,Cs,U and Th)and HFSE(e.g.Nd,Zr)contents make it very akin to the A-type granites.Its heterogenenous Sr(87Sr/86Sri=0.7049-0.7098)and Nd(εNdT=-1.05--4.04)isotope compositions preclude the possibility of a pure sedimentary or igneous source.Instead,its geochemical compositions suggest that it may be derived from partial melting of a complex source,which onsists of igneous and sedimentary rocks.Its intraplate characteristics,together with coeval mafic dykes, indicate an extensional environment at the end of Caledonian.The recognition of the extensional event does not support a continuous subduction-accretion model for the Paleozoic tectonic evolution of the West Kunlun Mountains.On the Contrary,it provides new evidence for the twostage island-arc model.

  11. Garcinia kola seeds: is the aqueous extract a true aphrodisiac in male Wistar rats?

    Science.gov (United States)

    Yakubu, M T; Quadri, A L

    2012-01-01

    The age long acclaimed aphrodisiac potentials of Garcinia kola seeds in some parts of Western Nigeria has not been substantiated with scientific evidence. In this study, we have decided to evaluate the effect of aqueous seed extract of G. kola at the doses of 25, 50 and 100 mg/kg body weight on sexual behaviour of male rats. Male rats weighing 215.00 ± 18.58 g were randomized completely into four groups (A-D) of six animals each. Animals in group A received, orally, 0.5 ml of distilled water only while those in groups B, C and D received same volume containing 25, 50 and 100 mg/kg body weight of the seed extract respectively. Frequencies of mount (MF), intromission (IF), genital toilet (GTF) and ejaculation (EF) as well as latencies of mount (ML), intromission (IL) and ejaculation (EL) were evaluated following the pairing of male rats (1:1) with non-oestrous female rats. The parameters were monitored for the first (15-30 min), second (75-90 min) and third (180195 min) observatory periods. The levels of testosterone, luteinizing (LH) and follicle stimulating hormones (FSH) were also determined. Phytochemical screening of the extract revealed the presence of saponins (2.78%), cardiac glycosides (0.26%), cardenolides and dienolides (0.24%), flavonoids (1.28%) and steroids (1.14%). The 25 and 100 mg/kg body weight increased (P<0.05) the MF whereas the ML was decreased by all the doses of the extract. MF and ML were not altered during the second observatory period whereas the 50 mg/kg body weight increased these parameters during the third observatory period. Other sexual behaviour parameters as well as serum testosterone, FSH and LH were not significantly altered throughout the observatory periods. Overall, the results revealed that G. kola seeds did not have sex enhancing potential as claimed. Therefore, the acclaimed pro sexual effect of Garcinia kola seeds is scientifically untrue. This study has refuted the claim that one of the rationales for consuming the seeds

  12. Adakitic-like magmatism in western Ossa-Morena Zone (Portugal): Geochemical and isotopic constraints of the Pavia pluton

    Science.gov (United States)

    Lima, S. M.; Neiva, A. M. R.; Ramos, J. M. F.

    2013-02-01

    Granitic rocks are a major component of the Earth's continental crust and occur in a wide variety of tectonic settings. Their chemical and isotopic characterization is crucial to the recognition of the potential sources and mechanisms involved in their generation. In this study, we present the first whole rock chemical and isotopic (Sr-Nd-O) data for the Pavia pluton (328-317 Ma), located near the western border of the Ossa-Morena Zone (Évora Massif, Portugal). Major and trace element geochemistry suggests that the different granitic phases composing this intrusive body (enclaves, granites (s.l.) and crosscutting dikes) represent independent magma pulses and the majority is similar to TTGs and adakites. The little Sr-Nd-O isotopic variation, with (87Sr/86Sr)328 = 0.70428-0.70560, ɛNd328 ranging between - 3.4 and + 0.4 and δ18O varying from + 5.6‰ to + 8.4‰ implies an isotopically similar protolith for all phases. The most viable mechanism for the generation of the Pavia pluton adakitic-like magmatism is assimilation-fractional crystallization of a mantle-derived magma. This mechanism was also invoked to explain the genesis of other plutons within the Évora Massif but they have a distinct chemistry (typical arc calc-alkaline rocks). The chemical differences between them and the Pavia pluton granitic rocks are interpreted as the result of lower degrees of crustal assimilation and higher degrees of contamination of mantle-derived magmas by the sinking slab (after subduction blocking and subsequent slab break-off).

  13. In Vitro Antilisterial Properties of Crude Methanol Extracts of Garcinia kola (Heckel Seeds

    Directory of Open Access Journals (Sweden)

    Dambudzo Penduka

    2012-01-01

    Full Text Available Crude methanol extracts of Garcinia kola (Heckel seeds were screened for their antilisterial activities against 42 Listeria bacteria isolated from wastewater effluents. The extract had activity against 45% of the test bacteria and achieved minimum inhibitory concentrations (MICs ranging between 0.157 and 0.625 mg/mL. The rate of kill of the extract was determined against four representative Listeria species in the study, and the results showed that the highest percentage of bacteria cells were killed after the maximum exposure time of 2 h at the highest concentration of 4×MIC value, with the maximum number of bacteria cells killed being for L. ivanovii (LEL 30 100%, L. monocytogenes (LAL 8 94.686%, L. ivanovii (LEL 18 60.330%, and L. grayi (LAL 15 56.071% We therefore conclude that the nature of inhibition of the crude methanol extracts of Garcinia kola seeds can be either bactericidal or bacteriostatic depending on the target Listeria species and can also differ among same species as evidenced by L. ivanovii strains LEL 30 and LEL 18.

  14. A refinement of the emission data for Kola Peninsula based on inverse dispersion modelling

    Directory of Open Access Journals (Sweden)

    M. Prank

    2010-11-01

    Full Text Available The study reviews the emission estimates of sulphur oxides (SOx and primary particulate matter (PM from the major industrial sources of Kola Peninsula. Analysis of the disagreements between the existing emission inventories for the Kola region combined with forward and inverse ensemble dispersion modelling, analysis of observation time-series and model-measurement comparison showed that the emission of the Nikel metallurgy plant was missing or strongly under-estimated in the major European emission inventories, such as EMEP, EDGAR, TNO-GEMS, and PAREST-MEGAPOLI. In some cases it was misplaced or mis-attributed to other sources of the region. A more consistent inventory of the anthropogenic emissions of SOx and PM has been compiled for the Peninsula, compared with the existing estimates and verified by means of dispersion modelling. In particular, the SILAM model simulations for 2003 and 2006 with the revised emission data showed much smaller under-estimation of SO2 concentrations at 8 Finnish and Norwegian observational stations. For the nearest site to the plant the 10-fold underestimation turned to a 1.5-fold over-prediction. Temporal correlation improved more moderately (up to 45% for concentrations, up to 3 times for deposition. The study demonstrates the value of a combined usage of forward and inverse ensemble modelling for source apportionment in case of limited observational data.

  15. A refinement of the emission data for Kola Peninsula based on inverse dispersion modelling

    Science.gov (United States)

    Prank, M.; Sofiev, M.; Denier van der Gon, H. A. C.; Kaasik, M.; Ruuskanen, T. M.; Kukkonen, J.

    2010-06-01

    The study reviews the emission estimates of sulphur oxides (SOx) and primary particulate matter (PM) from the major industrial sources of Kola Peninsula. Analysis of the disagreements between the existing emission inventories for the Kola region combined with forward and inverse ensemble dispersion modelling, analysis of observation time-series and model-measurement comparison showed that the emission of the Nikel non-ferrous metallurgy plant was missing from the EMEP inventory, as well as from some others, being in some cases misplaced or mis-attributed to other sources of the region. A more consistent inventory of the anthropogenic emissions of SOx and PM has been compiled for the peninsula, compared with the existing estimates and verified by means of dispersion modelling. In particular, the SILAM model simulations for 2003 and 2006 with the revised emission data showed much lower bias - up to 6 times for the most-affected sites - for SO2 with regard to the measured concentrations of 8 Finnish and Norwegian observational stations in the region. Temporal correlation improved moderately (10-20%) but homogeneously over Lapland. The study demonstrates the value of a combined usage of forward and inverse ensemble modelling for source apportionment in case of limited observational data.

  16. A refinement of the emission data for Kola Peninsula based on inverse dispersion modelling

    Directory of Open Access Journals (Sweden)

    M. Prank

    2010-06-01

    Full Text Available The study reviews the emission estimates of sulphur oxides (SOx and primary particulate matter (PM from the major industrial sources of Kola Peninsula. Analysis of the disagreements between the existing emission inventories for the Kola region combined with forward and inverse ensemble dispersion modelling, analysis of observation time-series and model-measurement comparison showed that the emission of the Nikel non-ferrous metallurgy plant was missing from the EMEP inventory, as well as from some others, being in some cases misplaced or mis-attributed to other sources of the region. A more consistent inventory of the anthropogenic emissions of SOx and PM has been compiled for the peninsula, compared with the existing estimates and verified by means of dispersion modelling. In particular, the SILAM model simulations for 2003 and 2006 with the revised emission data showed much lower bias – up to 6 times for the most-affected sites – for SO2 with regard to the measured concentrations of 8 Finnish and Norwegian observational stations in the region. Temporal correlation improved moderately (10–20% but homogeneously over Lapland. The study demonstrates the value of a combined usage of forward and inverse ensemble modelling for source apportionment in case of limited observational data.

  17. Radioactive sources of main radiological concern in the Kola-Barents region

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, R.; Baklanov, A

    1998-07-01

    This overview focuses on some major issues for risk analysis appearing in our recent study surveying radioactive sources on the Kola Peninsula, along with adjacent parts of the Arctic seas. The main issues of the parts are as follows: An introduction to the presence of radioactive sources and environmental contamination in the Barents Euro-Arctic Region and the current status as regards various significant studies. Radioactive contamination in man and the environment on the Kola Peninsula, as well as radioactive transfer during the last three decades from external sources to the Kola-Barents region. The main conclusion from the findings is that the contamination is generally relatively low and that neither the activity levels in samples of soil, vegetation, and the important food-chains, nor the content in man indicate any changes since 1986 that could not be explained by the combined effect of the cumulative deposition from the nuclear weapons testing and the accident in Chernobyl. The radioactive sources of main concern in the region belong to the following categories: nuclear power submarine and cruiser naval bases; civil nuclear power ice-breaker fleet; building and repairing shipyards; nuclear power plants; radioactive waste and spent nuclear fuel storage facilities; sunken reactors/ships; liquid radioactive waste dumping; solid radioactive waste dumping; nuclear weapon bases; nuclear weapon tests; civil nuclear explosions; nuclear accidents; mining radioactive ore deposits and plants; new projects and others. Several case studies concerning releases in the Kola-Barents region are reviewed, and followed by consequence analyses for the categories of primary interest covering: a) airborne releases from the Kola NPP, and from submarines or spent nuclear fuel; b) releases from objects in the marine environment including submarines, dumped reactors, and various other radioactive objects and waste; c) releases from liquid and solid wastes stored on land or during

  18. A ground-validated NDVI dataset for monitoring vegetation dynamics and mapping phenology in Fennoscandia and the Kola peninsula

    NARCIS (Netherlands)

    Beck, P.S.A.; Jonsson, P.; Hogda, K.A.; Karlsen, S.R.; Skidmore, A.K.; Eklundh, L.

    2007-01-01

    An NDVI dataset covering Fennoscandia and the Kola peninsula was created for vegetation and climate studies, using Moderate Resolution Imaging Spectroradiometer 16-day maximum value composite data from 2000 to 2005. To create the dataset, (1) the influence of the polar night and snow on the NDVI val

  19. An AMS study of the Takidani pluton (Japan)

    Science.gov (United States)

    Hartung, Eva; Caricchi, Luca; Floess, David; Wallis, Simon; Harayama, Satoru

    2016-04-01

    Large plutonic bodies are typically constructed incrementally often by under-accretion of distinct successive magma pulses. Petrography and geochemistry of the Takidani Pluton (1.54 Ma ± 0.23 Ma) in the Northern Japanese Alps show that the chemical and textural variability observed at the roof of this intrusion is best explained by the segregation of residual melt from a crystallising magma body. We carried out a magnetic susceptibility survey (bulk susceptibility and anisotropy of magnetic susceptibility) to identify the structures associated with the emplacement and extraction of residual melts from a magmatic mush. Additionally, we determined shape preferred orientations (SPO) of amphibole at several locations within the Takidani pluton. From bottom to top of the intrusion, the bulk susceptibility is about constant in the main granodioritic part, decreases roofwards within the porphyritic unit, before increasing again within the marginal granodiorite close to the contact with the overlaying Hotaka Andesite. Such variability mimics the major and trace elements compositional variability measured in the whole rock samples. Magnetic foliations are observed at the western tectonic contact of the pluton potentially indicating overprint, while most other magnetic fabrics across the pluton are characterised by triaxial ellipsoids of magnetic susceptibility or magnetic lineations. Our preliminary data and the lack of internal contacts indicate that Takidani Pluton was likely emplaced as a series of successive magma pulses finally merging to produce a large connected magma body. While amphibole foliations may likely be the results of super-solidus tectonic overprint, anisotropy of magnetic susceptibility data may be related to post-emplacement melt segregation.

  20. ABCGheritage project - promoting geotourism in northern Finland, northern Norway and the Kola Peninsula

    Science.gov (United States)

    Pihlaja, Jouni; Johansson, Peter; Lauri, Laura S.

    2014-05-01

    Nature tourism has been a growing business sector in the Barents area during the recent decades. With the purpose to develop nature tourism in a sustainable way, a cooperation project ABCGheritage - Arctic Biological, Cultural and Geological Heritage has been carried out. Project has received partial funding from the EU Kolarctic ENPI program. In the geoheritage part of the project the main activities were aimed to develop pro-environmental ways of geotourism in the area. The three main participants in the geoheritage part of the project are the Geological Survey of Finland, Northern Finland Office, the Geological Institute of the Kola Science Centre of the Russian Academy of Sciences and Bioforsk Soil and Environment from northeastern Norway. The duration of the project is 2012-2014 and most of the work has already been completed even if most of the results are not published yet. Totally ten different tasks have been implemented in the geological part of the project. The largest task has been the preparation of a geological outdoor map and guide book of the Khibiny Tundra locating in the central part of the Kola Peninsula. In Finland already 11 such maps have been published, and the experiences gained during their production have been used in this project, too. Geological heritage trails to the Khibiny Tundra have also been created and they will be drawn on the map. The second concrete result is the Barents Tour for Geotourist -guide, which will be published as a guide book, web pages and an exhibition. The route comprises ca 35 best geological demonstration sites along the circle route from northern Finland to northeastern Norway, from there to Kola Peninsula and then back to Finland. Information of the route will be available for all interested travelers. In addition to the geological outdoor map of the Khibiny Tundra and "Barents Tour for Geotourists"-guide, the primary outputs of the project are the geological nature trails on the field, geological

  1. The primary circuit materials properties results analysis performed on archive material used in NPP V-1 and Kola NPP Units 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    Kupca, L.; Beno, P. [Nuclear Power Plants Research Institute Inc., Trnava (Slovakia)

    1997-04-01

    A very brief summary is provided of a primary circuit piping material properties analysis. The analysis was performed for the Bohunice V-1 reactor and the Kola-1 and -2 reactors. Assessment was performed on Bohunice V-1 archive materials and primary piping material cut from the Kola units after 100,000 hours of operation. Main research program tasks included analysis of mechanical properties, corrosion stability, and microstructural properties. Analysis results are not provided.

  2. Alternative technologies for remediation of technogenic barrens in the Kola Subarctic

    Science.gov (United States)

    Koptsik, G. N.; Koptsik, S. V.; Smirnova, I. E.

    2016-11-01

    The efficiency of remediation of technogenic barrens under the reduction of air pollutant emissions from the Severonikel smelter in the Kola Subarctic is determined largely by the soil state and the technology applied. The covering of the contaminated soils with artificially made material based on organomineral substrates and the following liming and fertilization promoted a sharp and long-term reduction of acidity, decrease in the biological availability of heavy metals, increase in the supply with nutrients, and improvement of the life state of willow and birch plantations. The effect of economically more profitable chemo-phytostabilization is short-term; it requires constant maintenance. Under the current production and a high level of soil contamination, repeated measures are required to optimize the soil reaction, supply with nutrients, and to correct the availability of heavy metals in the soils based on the results of continuous monitoring

  3. Ten year trend analysis of malaria prevalence in Kola Diba, North Gondar, Northwest Ethiopia

    Directory of Open Access Journals (Sweden)

    Alemu Abebe

    2012-08-01

    Full Text Available Abstract Background Malaria is caused by protozoan parasites of the genus Plasmodium. It is one of the leading causes of illness and death in the world. It is a major public health problem in Ethiopia. Over the past years, the disease has been consistently reported as the first leading cause of outpatient visits, hospitalization and death in health facilities across the country. Methods A retrospective study was conducted to determine the prevalence of malaria from peripheral blood smear examinations from the Kola Diba Health Center of Ethiopia. The case notes of all malaria cases reported between 2002–2011 were carefully reviewed and analyzed. Additionally, any malaria intervention activities that had been taken to control malaria were collected using a well-prepared checklist from the study area. Results Within the last decade (2002–2011 a total of 59, 208 blood films were requested for malaria diagnosis in Kola Diba health center and 23,473 (39.6% microscopically confirmed malaria cases were reported in the town with a fluctuating trend. Regarding the identified plasmodium species, Plasmodium falciparum and Plasmodium vivax accounted for 75% and 25% of malaria morbidity, respectively. Malaria was reported in all age groups and both sexes, but the 15–44 year age group and males were more affected. Despite the apparent fluctuation of malaria trends in the area, the highest peak of malaria cases was reported during spring seasons. Conclusion Comparatively, after the introduction of the current malaria control strategies, the morbidity and mortality by malaria is decreasing but malaria is still a major health problem and the deadly species P. falciparium is predominant. Therefore, control activities should be continued in a strengthened manner in the study area considering both P. falciparium and P. vivax.

  4. Climatic variations on longest tree-ring chronologies for Kola Peninsula and Finnish Lapland

    Science.gov (United States)

    Kasatkina, E. A.; Shumilov, O. I.; Timonen, M.; Mielikainen, K.; Helama, S.; Kanatjev, A. G.; Kirtsideli, I. Yu.

    2010-05-01

    We investigated the external factor (solar activity, volcanic eruptions) influence on tree growth at high latitudes. We analysed a 561-year tree-ring record of pine (Pinus sylvestris L.) and a 676-year juniper (Juniperus Sibirica Burgst.) tree-ring chronology collected nearby the northern timberline (67.77-68.63N; 33.25-36.52 E) at the Kola Peninsula, northwestern Russia. As well known the climatic impacts of solar and volcanic activity vary regionally, and major volcanic eruptions do not always result in regional cooling. A response of tree growth at the Kola Peninsula to climatic changes due to solar variability and volcanic eruptions was revealed. For example, Dalton minimum of solar activity (1801-1816 AD) and Laki (1783 AD) and Tambora (1815 AD) volcanic eruptions appeared to cause the greatest ring-width reduction and cooling. The minima of solar activity Sporer (1416-1534 AD) and Maunder (1645-1715 AD) were as well accompanied by temperature decreases. Intervals with an absence of significant volcanic eruptions correspond to intervals of increased ring-width values. A superposed epoch analysis of 19 large (Volcanic Explosivity Index, VEI>5) volcanic events revealed a significant suppression of tree growth for up to 8 years following volcanic eruptions. The similar effect (supression of tree growth after powerful volcanic eruptions) was obtained under analysis of the 7641-year supra-long pine tree-ring chronology for Finnish Lapland. Our results documenting the regional climatic impacts of solar and volcanic activity permit us to understand the dynamics of the climate system and its response to external forcing. This work is financially supported by grant from Russian Foundation for Basic Research (grant No. 09-04-98801), by the Program of the Russian Academy and by the Regional Scientific Program of Murmansk region.

  5. Ferrobasalt-rhyolite immiscibility in tholeiitic volcanic and plutonic series (Invited)

    Science.gov (United States)

    Charlier, B.; Namur, O.; Kamenetsky, V. S.; Grove, T. L.

    2013-12-01

    One atmosphere experiments show that silicate liquid immiscibility develops between Fe-rich and Si-rich melts below 1000-1020°C in compositionally diverse lavas that represent classical tholeiitic trends, such as Mull, Iceland, Snake River Plain and Sept Iles. Extreme iron enrichment along the evolution trend is not necessary; immiscibility also develops during iron depletion and silica enrichment after Fe-Ti oxide saturation. Natural liquid lines of descent for major tholeiitic series also approach or intersect the experimentally-defined compositional space of immiscibility. The importance of ferrobasalt-rhyolite unmixing in both volcanic and plutonic environments is supported by worldwide occurrence of immiscible globules in the mesostasis of erupted basalts, and by unmixed melt inclusions in cumulus phases of major layered intrusions such as Sept Iles, Skaergaard and Sudbury. A clear case of liquid immiscibility is also recorded in intrusive tholeiitic gabbros from the Siberian Large Igneous Province and is evidenced by textures and compositions of millimeter-sized silicate melt pools trapped in native iron. An important implication of immiscibility in natural ferrobasaltic provinces is the development of a compositional gap characterized by the absence of intermediate compositions, a major feature observed in many tholeiitic provinces and referred to as the Daly gap. The compositions of experimental silica-rich immiscible melts coincide with those of natural rhyolites with high FeOtot and low Al2O3, which suggests a potential role for large-scale immiscibility in the petrogenesis of late-stage ferroan silicic melts. No evidence for the paired ferrobasaltic melt is observed in volcanic provinces, probably because of its uneruptable characteristics. Instead, Fe-Ti×P-rich gabbros crystallized at depth and are the cumulate products of immiscible Fe-rich melts in plutonic settings, a feature clearly evidenced in the Sept Iles intrusion. The production of

  6. Geochemical and Sr-Nd-Pb-O isotope composition of granitoids of the Early Cretaceous Copiapó plutonic complex (27°30'S), Chile

    Science.gov (United States)

    Marschik, Robert; Fontignie, Denis; Chiaradia, Massimo; Voldet, Pia

    2003-10-01

    Early Cretaceous plutonic rocks exposed south of Copiapó form part of the Coastal Batholith of northern Chile. These rocks intrude arc-derived volcanic and volcaniclastic rocks and marine limestones that were deposited in the Early Cretaceous Atacama backarc basin. The Copiapó plutonic complex consists mainly of calc-alkaline, medium- to coarse-grained diorite, granodiorite, tonalite, monzodiorite, and quartz monzonite. The plutonic rocks are subalkaline to alkaline, metaluminous, magnetite-series, volcanic arc, I-type granitoids. Batholithic magmas are a heat, potential fluid, metal, and sulphur source for the hydrothermal iron oxide-rich Cu-Au mineralization in the Candelaria-Punta del Cobre district. Ore-related hydrothermal alteration affected large portions of the Copiapó complex. The least altered batholithic rocks have initial 87Sr/ 86Sr of 0.703070-0.703231; initial 143Nd/ 144Nd of 0.512733-0.512781; and 206Pb/ 204Pb, 207Pb/ 204Pb, and 208Pb/ 204Pb of 18.428-18.772, 15.550-15.603, and 38.127-38.401, respectively. The δ18O values for these rocks range from +6.9 to +8.6‰. Isotope signatures and trace element distributions suggest that the magmas are mantle derived. A subduction fluid-modified mantle source may explain the geochemical characteristics of the Copiapó complex. The ascent of magmas occurred along deep-rooted structures without significant crustal contamination, though minor contamination by relatively young (e.g. Jurassic) igneous rocks during ascent is possible. Intrusive rocks with high-K to shoshonitic characteristics probably represent residual liquids of less evolved magmas. The regional geologic context suggests that the plutons of the Copiapó complex were emplaced at a relatively shallow crustal level of 2-3 km.

  7. SHRIMP U-Pb dating and geochemistry of the Cretaceous plutonic rocks in the Korean Peninsula: A new tectonic model of the Cretaceous Korean Peninsula

    Science.gov (United States)

    Kim, Sung Won; Kwon, Sanghoon; Park, Seung-Ik; Lee, Changyeol; Cho, Deung-Lyong; Lee, Hong-Jin; Ko, Kyoungtae; Kim, Sook Ju

    2016-10-01

    The Cretaceous tectonomagmatism of the Korean Peninsula was examined based on geochemical and geochronological data of the Cretaceous plutonic rocks, along with distribution of volcano-sedimentary nonmarine N- to NE-trending fault bounded sedimentary basins. We conducted sensitive high-resolution ion microprobe (SHRIMP) zircon U-Pb ages and whole-rock geochemical compositions of 21 Cretaceous plutonic rocks, together with previously published data, from the central to southern Korean Peninsula. Four age groups of plutonic rocks were identified: Group I (ca. 119-106 Ma) in the northern to central area, Group II (ca. 99-87 Ma) in the central southern area, Group III (ca. 85-82 Ma) in the central to southern area, and Group IV (ca. 76-67 Ma) in the southernmost area. These results indicate a sporadic trenchward-younging trend of the Cretaceous magmatism in the Korean Peninsula. The Group I, II, and III rocks are dominated by high-K calc-alkaline I-type rocks with rift-related A-type granitoids. In contrast, the Group IV rocks are high-K calc-alkaline I-type plutonic rocks with no A-type rocks. The geochemical signatures of the entire groups indicated LREEs (light rare earth elements) enrichments and negative Nb, Ta, and Ti anomalies, indicating normal arc magmatism. A new tectonic model of the Cretaceous Korean Peninsula was proposed based on temporal and spatial distribution of the Cretaceous plutons represented by four age groups; 1) magmatic quiescence throughout the Korean Peninsula from ca. 160 to 120 Ma, 2) intrusions of the I- and A-type granitoids in the northern and central Korean Peninsula (Group I plutonic rocks from ca. 120 to 100 Ma) resulted from the partial melting of the lower continental crust due to the rollback of the Izanagi plate expressed as the conversion from flat-lying subduction to normal subduction. The Gyeongsang nonmarine sedimentary rift basin in the Korean Peninsula and adakite magmatism preserved in the present-day Japanese Islands

  8. The microstructural effects of aqueous extract of Garcinia kola (Linn) on the hippocampus and cerebellum of malnourished mice

    Institute of Scientific and Technical Information of China (English)

    Sunday A Ajayi; David A Ofusori; Gideon B Ojo; Oladele A Ayoka; Taiwo A Abayomi; Adekilekun A Tijani

    2011-01-01

    Objective: To assess the neuroprotective effects of aqueous extract of Garcinia kola on neurotoxin administered malnourished mice adopting histological procedure. Methods: The study was carried out using thirty-two adult malnourished mice which were randomly assigned into four groups (n=8): A, B, C and D. Group A served as control, while the other groups served as the experimental groups. Animals in group A were fed malnourished diet ad libitum and given water liberally. Animals in group B were administered with 3-Nitropropionic acid (3-NP) (neurotoxin) only at 20 mg/kg body weight, group C were given only Garcinia kola extracts, and group D were pre-treated with Garcinia kola extracts at 200 mg/kg for seven days prior to administration of neurotoxin at 20 mg/kg body weight. After three days of neurotoxins administration in the relevant groups, the brains were excised and fixed in formal calcium for histological processing. Results:The study showed that hippocampal and cerebellar neurons of animals in group B exhibited some cellular degeneration and blood vessel blockage, which were not seen in groups A, C and D. Cresyl violet staining was least intense in group B than in groups A, C and D. Despite the fact that animals in group D has equal administration of 3-Nitropropionic acid concentration, there were no traces of neural degeneration as it was evidenced in group B. Conclusions: It is concluded that Garcinia kola has protective effects on the neurons of the hippocampus and cerebellum of malnourished mice.

  9. Norite and charnockites from the Venda Nova Pluton, SE Brazil: Intensive parameters and some petrogenetic constraints

    Directory of Open Access Journals (Sweden)

    Julio Cezar Mendes

    2012-11-01

    Full Text Available The Venda Nova Pluton (VNP is a zoned ring structure emplaced in the southern portion of the Neoproterozoic Araçuai Belt, in Espírito Santo, Brazil. It is a slightly westward tilted cylinder-like intrusion, with an almost circular horizontal section. In the center of this structure, an off-centered gabbro-noritic core, surrounded by syeno-monzonitic rocks, intrudes an outer ring of charnockites and norite. These envelop the syeno-monzonitic and gabbro-noritic center, as a narrow discontinuous belt. While, in the core intrusion, mingling and mixing processes are widespread and well documented in the literature, in the outer ring, the norite and charnockite layers show predominantly homogeneous and isotropic internal structures. Nevertheless, smaller interaction zones between charnockites and norite denote a comparatively more restricted mingling process. The norite is a fine-grained rock with hypidiomorphic granular to intergranular texture. The charnockites are medium-grained and made up of: (a orthopyroxene-tonalite, (b orthopyroxene-quartz-diorite, and (c orthopyroxene-granodiorite with hypidiomorphic granular to porphyritic textures. In all lithotypes both ortho- and clinopyroxene are replaced by hornblende and biotite. Two contrasting compositional sequences have been recognized, based on whole rock geochemistry: (1 a basic, with tholeiitic affinities (norite and, (2 an intermediate, medium-K calc-alkaline, comprising the charnockites. Estimated crystallization temperatures, which have been calculated from micro-probe analysis of pyroxenes, range from 915 ± 25 °C to 960 ± 50 °C. Re-equilibration temperature (ilmenite-magnetite calibration is around 600 ± 50 °C. This indicates oxygen fugacities four order of magnitude below the FMQ-buffer and a reduced environment. Coeval pressure conditions estimated from the Al-content in hornblende range from 5.5 ± 0.6 kbar. Data obtained for the norite point toward an evolution from

  10. The Precambrian/Lower Cambrian pluton from Vila Nova (Central Portugal

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    Reis, A. I.M.

    2010-06-01

    Full Text Available The Vila Nova pluton is a small, Pre-Variscan granitic body that intruded rocks of the Central Iberian Zone near the contact with the Ossa Morena Zone and is affected by several shear zones and faults. Its contact metamorphic aureole is constituted by micaschist with porphyroblasts in the outer zone and hornfels in the inner zone. Small metasedimentar xenoliths are dispersed all over the body. The pluton has a great mineralogical heterogeneity with pronounced variations in muscovite/biotite and plagioclase/microcline contents and is classified as granite, granodiorite or tonalite. It is a leucogranite, highly peraluminous (A/CNK = 1.31 – 1.64, magnesian and calc-alkaline to alkaline-calcic. The variation diagrams show curvilinear trends with silica. Eu/Eu* = 0.47 – 0.77 and there is a slight enrichment in LREE relative to HREE. The normalized diagrams indicated dominantly crustal granite, related to subduction. U-Pb isotopic data of zircon and monazite gives 540-542 Ma age.

    El plutón de Vila Nova es un pequeño cuerpo granítico pre-varisco, que intruyó en las rocas de la Zona Centro Ibérica, cerca del contacto con la Zona de Ossa Morena, siendo afectado por varias fallas y zonas de cizalla. Su aureola de metamorfismo de contacto consiste en esquistos con porfiroblastos y corneanas. Pequeños xenolitos metasedimentarios aparecen dispersos por todo el cuerpo granítico. Presenta una gran diversidad mineralógica, con amplias variaciones en las relaciones biotita/moscovita y microclina/plagioclasa, siendo clasificado como tonalita-granodiorita-granito. Se trata de un leucogranito fuertemente peralumínico (A/CNK = 1.31 – 1.64, magnesiano y calco-alcalino a alcalino-cálcico. Los diagramas muestran variaciones curvilíneas con la variación de sílice. Eu/Eu* = 0.47 – 0.77 y hay un ligero enriquecimiento de LREE en relación con HREE. Los diagramas indican que la norma es un granito dominante de la corteza, relacionados con la

  11. Geochronology and Geochemical Characteristics of the Early Mesozoic Tangquan Pluton in Southwestern Fujian and Its Tectonic Implications

    Institute of Scientific and Technical Information of China (English)

    MAO Jianren; HU Qing; XU Naizheng; XIE Fanggui; TAO Kuiyuan

    2003-01-01

    The Tangquan granodioritic pluton in Datian County, southwestern Fujian, China, which extends in a NE direction with an exposed area of about 130 km2, used to be considered a product of Early Cretaceous magmatism. The present study suggests for the first time that the pluton was formed in the Early Jurassic by using multiple methods for isotopic dating, which give zircon U-Pb ages of 186.8 Ma and 179.0 Ma, Rb-Sr isochron age of 162.02(4.5 Ma, and biotite 40Ar/39Ar plateau age of 158.1(0.7 Ma. The cooling rate for the pluton was relatively low (4.76°C/Ma) during the early stage (183(162 Ma) because of the compressional environment. It was emplaced in a higher cooling rate (50°C/Ma) in an extensional environment during the later stage (162(158 Ma). The granodiorites are metaluminous(peraluminous, relatively enriched in Na2O and depleted in K2O, and characteristic of I-type granites of crust-mantle mixed sources. They are moderately enriched in Rb, Th, Hf and LREE, and depleted in Ti, Nb, Ta and Sr, and have geochemical features of cal-alkaline rocks of an island arc or active continental margin. Their (87Sr/86Sr)i ratio varies from 0.70769 to 0.70822, εNd(t) from -9.68 to -10.07 and TDM from 1.52 to 1.55 Ga. They were formed by mixing of mantle-derived mafic magma with the granitic magma resulting from partial melting of crust-derived materials in an upwelling of the asthenospheric mantle in South China during the Early Mesozoic.

  12. Zircon U-Pb age, Lu-Hf isotope, mineral chemistry and geochemistry of Sundamalai peralkaline pluton from the Salem Block, southern India: Implications for Cryogenian adakite-like magmatism in an aborted-rift

    Science.gov (United States)

    Renjith, M. L.; Santosh, M.; Li, Tang; Satyanarayanan, M.; Korakoppa, M. M.; Tsunogae, T.; Subba Rao, D. V.; Kesav Krishna, A.; Nirmal Charan, S.

    2016-01-01

    The Sundamalai peralkaline pluton is one among the Cryogenian alkaline plutons occurring in the Dharmapuri Rift Zone (DRZ) of the Salem Block in the Southern Granulite Terrane (SGT) of India. Here we present zircon U-Pb age and Lu-Hf isotopic composition, mineral chemistry and geochemistry of the pluton to explore the petrogenesis and geodynamic implications. Systematic modal variation of orthoclase, Na-plagioclase, Ca-amphibole (ferro-edenite and hastingsite) and quartz developed quartz-monzonite and granite litho units in the Sundamalai pluton. Thermometry based on amphibole-plagioclase pair suggests that the pluton was emplaced and solidified at around 4.6 kbar pressure with crystallization of the major phases between 748 and 661 °C. Estimated saturation temperature of zircon (712-698 °C) is also well within this range. However, apatite saturation occurred at higher temperatures between 835 and 870 °C, in contrast with monazite saturation (718-613 °C) that continued up to the late stage of crystallization. Estimated oxygen fugacity values (log fO2: -14 to -17) indicate high oxidation state for the magma that stabilized titanite and magnetite. The magmatic zircons from Sundamalai pluton yielded a weighted mean 206Pb/238U age of 832.6 ± 3.2 Ma. Geochemically, the Sundamalai rocks are high-K to shoshonitic, persodic (Na2O/K2O ratio > 1), silica-saturated (SiO2:65-72 wt.%), and peralkaline in composition (aluminum saturation index, ASI effect) controlled differentiation between quartz-monzonite and granite. Both rock types have high content of Na2O (5.1-6.3 wt.%), Ba (350-2589 ppm) and Sr (264-1036 ppm); low content of Y (8.7-17 ppm) and Yb (0.96-1.69 ppm); elevated ratios of La/Yb (11-46) and Sr/Y (46-69) and are depleted in Ti, with a positive Sr anomaly suggesting an adakite-like composition and garnet controlled melting of a plagioclase-poor source. The low content of MgO (aborted rifting along the DRZ generating the magma that crystallized the Sundamalai

  13. Petrographical and geochemical characterization and deformation conditions of the San Cristobal pluton, Sierra de Velasco, La Rioja, Argentina; Caracterizacion petrografica y geoquimica y condiciones de deformacion del pluton San Cristobal, Sierra de Velasco, La Rioja, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Bellos, L.I.; Toselli, A.J.; Rossi, J.N.; Grosse, P.; Rosa, J.D. de la; Castro, A.

    2010-07-01

    The San Cristobal pluton is a 35 km2 granitic body that outcrops at the southestern tip of the Sierra de Velasco, located west of La Rioja city, Argentina. It is formed by monzogranites and syenogranites, together with scarce granodiorites, with medium to fine-grained, equigranular to slightly porphyritic textures. Their mineral assemblage consists of quartz + microcline + plagioclase + biotite {+-} muscovite + zircon + apatite + magnetite. The granite contains dioritic to tonalitic mafic enclaves. The central and eastern parts of the granite have been deformed by the NNW-SSE trending South Mylonitic shear zone formed by mylonitic rocks. The metamorphic host-rock is represented by scarce greenschist facies xenoliths and hornfels with the high T/P assemblage K-feldspar - cordierite - biotite {+-} sillimanite. The granites are calc-alkaline, weak- to moderately peraluminous, and formed as part of a continental magmatic arc developed along the active margin of western Gondwana during the Early Paleozoic. The depth of emplacement of the San Cristobal pluton is estimated at {approx}12 km. (Author).

  14. Neogene Uplift and Exhumation of Plutonic Bodies in the Beni Bou Ifrour Massif (Nador, northeastern Morocco)

    Science.gov (United States)

    Lebret, Noëmie; Jolivet, Laurent; Branquet, Yannick; Bourdier, Jean-Louis; Jolivet, Marc; Marcoux, Eric

    2013-04-01

    In Neogene times, the whole Mediterranean Sea was the center of an intense magmatic activity. This post-collisional magmatism produced a large amount of volcanic edifices through the Alpine belts, together with some intrusives. These plutonic bodies can be associated with skarn-type mineralization, well-known in Elba Island or Serifos Island (Cyclades), where they are generally exhumed by detachment faults. In Morocco, the plutons hosted by the Beni Bou Ifrour massif are connected to the biggest skarn-type iron concentrations of the country (production > 60 Mt, reserves ≈ 25 Mt). The purpose of this work is to explain the late uplift of this massif and subsequent exhumation of the intrusives. As a final product of the Africa-Eurasia plate convergence since ca. 70 Ma, the Rif Mountains constitute the westernmost segment of the Mediterranean Alpine belts. In the oriental part of this range, volcanic summits and Paleozoic to Mesozoic massifs outcrop in the surrounding Mio-Pliocene plains. The Beni Bou Ifrour massif, in the Nador province, consists in a dome-shaped folded Mesozoic series (Domerian to Barremian) affected by a slight epizonal regional metamorphism (ca. 14-12 Ma), dislocated by Neogene NE-SW faults and eventually sealed by upper Miocene transgressive sediments. The hosted intrusives (7.58 ± 0.03 Ma; Duggen et al., 2005) are the plutonic equivalents to the potassic calc-alkaline lavas (andesites mainly) from the surrounding "satellite" volcanic massifs. They turn out to stand in higher topographic position than the younger shoshonitic lavas of the neighboring Gourougou stratovolcano (6.12 ± 0.01 Ma; Duggen et al., 2005). Previous studies have attributed this uplift to the action of normal faults (pull-apart basins; Guillemin & Houzay, 1982), thrusting (Kerchaoui, 1985; 1995) or even of a caldeira resurgence (El Bakkali, 1995). To discriminate against those exhumation mechanisms, field work has been performed, coming along with new cross-sections to

  15. Geochronology of Zircon from Modern Plutons Beneath Two Contrasting Arc Volcanoes

    Science.gov (United States)

    Bacon, C. R.

    2006-12-01

    Ion microprobe (SHRIMP RG) 238U-230Th zircon dating documents recent crystallization of shallow plutons beneath two caldera volcanoes where magmas evolved mainly by crystallization differentiation. Mount Mazama, Oregon, is a medium-K calc-alkaline Cascade arc volcano whose 7.7-ka climactic eruption ejected granodiorite and related plutonic blocks during formation of Crater Lake caldera. Mount Veniaminof, Alaska, is a medium-K tholeiitic Aleutian arc volcano that ejected granodiorite, diorite, and gabbro blocks in its 3.7-ka caldera-enlarging eruption. Zircons in four granodiorite blocks from Mazama crystallized at various times between 20 ka and greater than 300 ka, with concentrations of model ages near 50-70, 110, and 200 ka that correspond to periods of dacitic volcanism dated by K-Ar (Bacon and Lowenstern, 2005, EPSL 233:277-293). Multiple-age zircon populations are common. The youngest zircon model ages in blocks from different locations around the caldera are similar to ages of nearby volcanic vents and may help map the distribution of intrusions within a composite pluton. Mazama zircons typically have many 10's to 100's of ppm U and Th, and grew relatively late in high- crystallinity magmas. U-Th model ages of zircon from a 27-ka rhyodacite, the only eruptive unit known with common zircon, are similar to those from granodiorite. Survival of these recycled crystals in zircon- undersaturated hydrous rhyodacitic magma suggests little time from entrainment to the 27-ka eruption. In contrast, the voluminous 7.7-ka climactic rhyodacite is virtually lacking in zircon, indicating dissolution of any granodioritic debris in the hot, vigorously growing silicic magma body during the intervening period. Veniaminof erupted basaltic through rhyodacitic magmas over the past 250 kyr. Gabbro, diorite, and miarolitic granodiorite blocks from Veniaminof represent cumulate mush and vapor-saturated residual melt segregations (Bacon, Sisson, and Mazdab, 2006, EOS 87:36:U41B-05

  16. Fracture controls on valley persistence: the Cairngorm Granite pluton, Scotland

    Science.gov (United States)

    Hall, A. M.; Gillespie, M. R.

    2016-12-01

    Valleys are remarkably persistent features in many different tectonic settings, but the reasons for this persistence are rarely explored. Here, we examine the structural controls on valleys in the Cairngorms Mountains, Scotland, part of the passive margin of the eastern North Atlantic. We consider valleys at three scales: straths, glens and headwater valleys. The structural controls on valleys in and around the Cairngorm Granite pluton were examined on satellite and aerial photographs and by field survey. Topographic lineaments, including valleys, show no consistent orientation with joint sets or with sheets of microgranite and pegmatitic granite. In this granite landscape, jointing is not a first-order control on valley development. Instead, glens and headwater valleys align closely to quartz veins and linear alteration zones (LAZs). LAZs are zones of weakness in the granite pluton in which late-stage hydrothermal alteration and hydro-fracturing have greatly reduced rock mass strength and increased permeability. LAZs, which can be kilometres long and >700 m deep, are the dominant controls on the orientation of valleys in the Cairngorms. LAZs formed in the roof zone of the granite intrusion. Although the Cairngorm pluton was unroofed soon after emplacement, the presence of Old Red Sandstone (ORS) outliers in the terrain to the north and east indicates that the lower relief of the sub-ORS basement surface has been lowered by 1 km of vertical erosion and for 400 Myr. This valley persistence is a combined product of regionally low rates of basement exhumation and of the existence of LAZs in the Cairngorm pluton and sub-parallel Caledonide fractures in the surrounding terrain with depths that exceed 1 km.

  17. New petrographic, geochemical and geochronological data for the Reguengos de Monsaraz pluton (Ossa Morena Zone, SW Iberian Massif, Portugal)

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, A.; Santos, J. F.; Azevedo, M. R.; Mendez, M. H.; Ribeiro, S.

    2010-07-01

    The Reguengos de Monsaraz pluton is a late to post-tectonic Variscan intrusion occurring in the Ossa Morena Zone (Iberian Variscan Chain). The dominant lithological types are tonalites and granodiorites, but the internal area of the massif is composed of gabbro-dioritic rocks. Field evidence shows that the intrusion is heterogeneous at mesoscopic scale suggesting that the emplacement of mafic and felsic magmas was contemporaneous. Petrographic and geochemical studies reveal that the different lithologic types define a continuous sequence with compositions varying from metaluminous to slightly peraluminous and a typical calc-alkaline signature. In Harker variation diagrams, it is possible to observe systematic rectilinear correlations pointing to the involvement of magma mingling/mixing processes in the petrogenesis of this sequence. Rb-Sr isotopic data, using a mineral-mineral pair from a granodiorite sample, yielded an age of 298 Ma, interpreted as a cooling age after igneous crystallization. (Author) 13 refs.

  18. Petrogenesis and tectonic implications of the Early Carboniferous to the Late Permian Barleik plutons in the West Junggar (NW China)

    Science.gov (United States)

    Liu, Bo; Han, Bao-Fu; Ren, Rong; Chen, Jia-Fu; Wang, Zeng-Zhen; Zheng, Bo

    2017-02-01

    The Paleozoic accretionary orogenesis and continental crustal growth in Central Asia are thought to have close relationship with the evolution of the Paleo-Asian Ocean (PAO). The well-exposed plutons in the northern Barleik Mountains of the West Junggar region, NW China, may provide essential insights into the evolution of the Junggar Ocean, a branch of the PAO, and mechanism of continental crustal growth. Our work on the Barleik plutons indicates an early suite of 324-320 Ma diorite and a late suite of 314-259 Ma quartz syenite and granitic porphyry. All the plutons are characterized by high-K calc-alkaline to shoshonitic signatures, varying depletion in Nb, Ta, Sr, P, Eu, and Ti, low initial 87Sr/86Sr ratios (0.70241-0.70585), strongly positive εNd(t) values (+ 5.7-+7.7), and young one-stage Nd model ages (390-761 Ma), suggesting that they resulted from different batches of magma that were produced by fractional crystallization of a metasomatized mantle source with minor crustal contamination. The diorite is coeval with the youngest arc magmatic rocks, indicating a subduction-related origin. By contrast, the quartz syenite and granitic porphyry are geochemically similar to A2-type granites, with high Zr, Ga, and FeOT/[FeOT + MgO], and are coeval with the widespread plutons in the West Junggar. This, together with the occurrence of Late Carboniferous fluvial deposits and the lack of < 320 Ma ophiolitic and subduction-related metamorphic lithologies, definitively indicates a post-collisional setting after the closure of the Junggar Ocean. Slab breakoff accompanied by asthenospheric upwelling and basaltic underplating is a possible geodynamic process that is responsible for the post-collisional magmatism and vertical crustal growth in the region. Thus a tectonic switch from subduction to post-collision started at the end of the Early Carboniferous ( 320 Ma), probably as a result of the final closure of the Junggar Ocean.

  19. Reconnaissance study of the Taylor Mountains pluton, southwestern Alaska

    Science.gov (United States)

    Hudson, Travis L.; Miller, Marti L.; Klimasauskas, Edward P.; Layer, Paul W.

    2010-01-01

    The Taylor Mountains pluton is a Late Cretaceous to early Tertiary (median age 65 + or ? 2 Ma) epizonal, composite biotite granite stock located about 235 km (145 mi) northeast of Dillingham in southwestern Alaska. This 30 km2 (12 mi2) pluton has sharp and discordant contacts with hornfels that developed in Upper Cretaceous clastic sedimentary rocks of the Kuskokwim Group. The three intrusive phases in the Taylor Mountains pluton, in order of emplacement, are (1) porphyritic granite containing large K-feldspar phenocrysts in a coarse-grained groundmass, (2) porphyritic granite containing large K-feldspar and smaller, but still coarse, plagioclase, quartz, and biotite phenocrysts in a fine-grained groundmass, and (3) fine-grained, leucocratic, equigranular granite. The porphyritic granites have different emplacement histories, but similar compositions; averages are 69.43 percent SiO2, 1.62 percent CaO, 5.23 percent FeO+MgO, 3.11 percent Na2O, and 4.50 percent K2O. The fine-grained, equigranular granite is distinctly felsic compared to porphyritic granite; it averages 75.3 percent SiO2, 0.49 percent CaO, 1.52 percent FeO+MgO, 3.31 percent Na2O, and 4.87 percent K2O. Many trace elements including Ni, Cr, Sc, V, Ba, Sr, Zr, Y, Nb, La, Ce, Th, and Nd are strongly depleted in fine-grained equigranular granite. Trace elements are not highly enriched in any of the granites. Known hydrothermal alteration is limited to one tourmaline-quartz replacement zone in porphyritic granite. Mineral deposits in the Taylor Mountains area are primarily placer gold (plus wolframite, cassiterite, and cinnabar); sources for these likely include scattered veins in hornfels peripheral to the Taylor Mountain pluton. The granite magmas that formed the Taylor Mountains pluton are thought to represent melted continental crust that possibly formed in response to high heat flow in the waning stage of Late Cretaceous subduction beneath interior Alaska.

  20. Accounting for local meteorological effects in the ozone time-series of Lovozero (Kola Peninsula

    Directory of Open Access Journals (Sweden)

    O. A. Tarasova

    2003-01-01

    Full Text Available The relationship between local meteorological conditions and the surface ozone variability was studied by means of statistical modeling, using ozone and meteorological parameters measured at Lovozero (250 m a.s.l., 68.5°N, 35.0°E, Kola Peninsula for the period of 1999-2000. The regression model of daily mean ozone concentrations on such meteorological parameters as temperature, relative humidity and wind speed explains up to 70% of day-to-day ozone variability in terms of meteorological condition changes, if the seasonal cycle is also considered. A regression model was created for separated time scales of the variables. Short-term, synoptical and seasonal components are separated by means of Kolmogorov-Zurbenko filtering. The synoptical scale variations were chosen as the most informative from the point of their mutual relation with meteorological parameters. Almost 40% of surface ozone variations in time periods of 11-60 days can be explained by the regression model on separated scales that is 30% more efficient than ozone residuals usage. Quantitative and qualitative estimations of the relations between surface ozone and meteorological predictors let us preliminarily conclude that at the Lovozero site surface ozone variability is governed mainly by dynamical processes of various time scale rather than photochemistry, especially during the cold season.

  1. Cardioprotective effect of Kolaviron (Garcinia kola seed extract in cholesterol-fed rats.

    Directory of Open Access Journals (Sweden)

    NWANERI-CHIDOZIE V. O.

    2014-03-01

    Full Text Available Flavonoids – a group of polyphenolic substances are naturally present in vegetables, fruits, seeds and beverages such as tea and wine. Studies have shown that flavonoid intake is inversely correlated with mortality from coronary heart diseases and myocardial infarction. The effect of kolaviron (a flavonoid complex extracted from Garcinia kola seeds on the organ weights (lungs, kidneys, heart, spleen and liver of rats administered with cholesterol, five times a week, for eight consecutive weeks was investigated. The results revealed that cholesterol administration at a dose of 30mg/day for eight consecutive weeks caused a significant increase (p<0.001 in relative heart weights of the cholesterol-fed rats when compared with the control. However, co-treatment with kolaviron at doses 100 and 200mg/kg significantly (p<0.001 reduced the cholesterol induced enlargement of the heart. This is a pointer to the cardioprotective potential of kolaviron; and thus suggests a possible use as a dietary supplement for the prevention and management of coronary heart diseases.

  2. Anodes for alkaline electrolysis

    Science.gov (United States)

    Soloveichik, Grigorii Lev

    2011-02-01

    A method of making an anode for alkaline electrolysis cells includes adsorption of precursor material on a carbonaceous material, conversion of the precursor material to hydroxide form and conversion of precursor material from hydroxide form to oxy-hydroxide form within the alkaline electrolysis cell.

  3. Crustal thickening prior to 220 Ma in the East Kunlun Orogenic Belt: Insights from the Late Triassic granitoids in the Xiao-Nuomuhong pluton

    Science.gov (United States)

    Xia, Rui; Wang, Changming; Deng, Jun; Carranza, Emmanuel John M.; Li, Wenliang; Qing, Min

    2014-10-01

    The East Kunlun Orogenic Belt (EKOB) played an important role in plate tectonics, magma generation, and crustal evolution. Late Triassic granodiorites and their mafic micro-granular enclaves (MMEs) from Xiao-Nuomuhong in the EKOB were studied for geochemistry and geochronology to constrain their petrogenesis. Zircon LA-ICP-MS dating indicates that the Xiao-Nuomuhong granodiorites are coeval with their MMEs (∼222 Ma). The granodiorites are high-K calc-alkaline rocks that are enriched in Rb, Th, U and LREE, and depleted in Cr, Ni and HFSE, with high Sr/Y ratios (82.2-85.3) and geochemically resemble the lower crust-derived adakites. The MMEs are also high-K calc-alkaline rocks, with high Al2O3 (16.8-18.8 wt.%), low Mg# (30-40), Nb, Zr and Hf, with weak negative Eu anomalies (Eu/Eu# = 0.8-0.9). We suggest the MMEs are mafic magmatic globules that were injected into the felsic host magma. The adakitic rocks from the Xiao-Nuomuhong pluton were generated by partial melting of thickened crust, while the primitive compositions of the MMEs were most likely from the lithospheric mantle beneath the EKOB. The Late Triassic Xiao-Nuomuhong pluton is important evidence that crustal thickening in the EKOB occurred prior to 220 Ma. The pluton is interpreted as the result of mixing between thickened lower crust-derived melts and lithospheric mantle-derived mafic melts and the protracted magmatic response to the break-off of the Paleo-Tethys oceanic slab at ∼232 Ma.

  4. Use of Digital Elevation Models to understand map landforms and history of the magmatism Khibiny Massif (Kola Peninsula, Russia)

    Science.gov (United States)

    Chesalova, Elena; Asavin, Alex

    2016-04-01

    most intense free gas emission. The technical possibilities that are offered by Remote Sensing (RS) and Geographical Information Systems (GIS) facilitate the geomorphological investigation of inhospitable and inaccessible mountain areas Digital Elevation Models (DEMs) are valuable tools for approximation of the real world's continuous surface. They allow a visual analysis of the earth's surface morphology, quanti?cation of sediment volumes and the calculation of topographic derivatives such as the slope gradient, slope aspect and pro?le curvature that consume ?eld investigations and optimize time The project has been sponsored by programmm Presidium of RAS P44. Reference Ivanyuk G, Kalashnikov A, Mikhailova J, Konoplyova N, Goryainov P, Yakovenchuk V, Pakhomovsky Y. Self-Organization of the Khibiny Alkaline Massif (Kola Peninsula, Russia). In Earth Sciences, Dr. Imran Ahmad Dar(Ed.), ISBN: 978-953-307-861-8, InTech, Available from: http://www.intechopen.com/books/earth-sciences/self-organization-of-the-khibiny-alkaline -massif -kolapeninsula-russia INTECH Open Access Publisher; 2012, Head7, P.131-156.

  5. Analysis of ISO/IEC 17025 for establishment of KOLAS (Korea Laboratory Accreditation Scheme) quality assurance system

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ji Hee

    2000-12-01

    Besides one existent accredited lab, radioactive material chemical analysis lab, five test laboratories and two calibration labs are under plan to acquire the accreditation from KOLAS. But the current Quality Manual was developed according to ISO Guide 25 that was superceded by ISO/IEC 17025. Since it is tailored to the radioactive material chemical analysis lab, a number of requirements of the Manual are not applicable to the labs other than radioactive material chemical analysis lab. Through the analysis of ISO/IEC 17025, a model of quality system was established which is not only consistent with ISO/IEC 17025 but reflective of the KAERI's situation.

  6. Dynamics of metamorphism processes by the fractal textures analysis of garnets, amphiboles and pyroxenes of Lapland Granulite Belt, Kola Peninsula

    Directory of Open Access Journals (Sweden)

    Miłosz A. Huber

    2012-01-01

    Full Text Available About thousand analyzes of garnet, amphibole and pyroxene crystals from selected samples of amphibolite and granulite rocks from Lapland Granulite Belt in Kandalaksha region (Kola Peninsula has been made. Indicated fractal-box dimension of studied minerals has a good correlation with tectonic zones, lead to a new insight in the dynamics of processes, which has modified the examined region. Fractal-box dimension makes the textural analysis more precise, because it consents for the mathematic and repeated review of crystals topology depending directly on processes which had created them.

  7. Perspectives of humic substances application in remediation of highly heavy metals contaminated soils in Kola Subarctic

    Science.gov (United States)

    Tregubova, Polina; Turbaevskaya, Valeria; Zakharenko, Andrey; Kadulin, Maksim; Smirnova, Irina; Stepanov, Andrey; Koptsik, Galina

    2016-04-01

    Northwestern part of Russia, the Kola Peninsula, is one of the most heavy metals (HM) contaminated areas in the northern hemisphere. The main polluters, mining-and-metallurgical integrated works "Pechenganikel" and "Severonikel", are surrounded by heavily damaged barren lands that require remediation. The main contaminating metals are Ni and Cu. Using of exogenous humic substances could be possible effective and cost-efficient solution of HM contamination problem. Rational application of humates (Na-K salts of humic acids) can result in improvement of soil properties, localization of contamination and decreasing bioavailability through binding HM in relatively immobile organic complexes. Our research aim was to evaluate the influence of increasing doses of different origin humates on i) basic properties of contaminated soils; ii) mobility and bioavailability of HMs; iii) vegetation state and chemistry. In summer 2013 a model field experiment was provided in natural conditions of the Kola Peninsula. We investigated the Al-Fe-humus abrazem, soil type that dominates in technogenic barren lands around the "Severonikel" work. These soils are strongly acid: pHH2O was 3.7-4.1; pHKCl was 3.4-4.0. The exchangeable acidity is low (0.8-1.6 cmol(+)/kg) due to the depletion of fine particles and organic matter, being the carriers of exchange positions. The abrazems of barrens had lost organic horizon. 12 sites were created in 1 km from the work. In those sites, except 2 controls, various amendments were added: i) two different by it's origin types of humates: peat-humates and coal-humates, the last were in concentrations 0.5% and 1%; ii) lime; iii) NPK-fertilizer; iv) biomates (organic degradable cover for saving warm and erosion protection). As a test-culture a grass mixture with predominance of Festuca rubra and Festuca ovina was sowed. As a result we concluded that humates of different origin have unequal influence on soil properties and cause decreasing as well as

  8. THE PALEOPROTEROZOIC IMANDRA-VARZUGA RIFTING STRUCTURE (KOLA PENINSULA: INTRUSIVE MAGMATISM AND MINERAGENY

    Directory of Open Access Journals (Sweden)

    V. V. Chashchin

    2015-09-01

    Full Text Available The article provides data on the structure of the Paleoproterozoic intercontinental Imandra-Varzuga rifting structure (IVS and compositions of intrusive formations typical of the early stage of the IVS development and associated mineral resources. IVS is located in the central part of the Kola region. Its length is about 350 km, and its width varies from 10 km at the flanks to 50 km in the central part. IVS contains an association of the sedimentary-volcanic, intrusive and dyke complexes. It is a part of a large igneous Paleoproterozoic province of the Fennoscandian Shield spreading for a huge area (about 1 million km2, which probably reflects the settings of the head part of the mantle plume. Two age groups of layered intrusions were associated with the initial stage of the IVS development. The layered intrusions of the Fedorovo-Pansky and Monchegorsk complexes (about 2.50 Ga are confined to the northern flank and the western closure of IVS, while intrusions of the Imandra complex (about 2.45 Ga are located at the southern flank of IVS. Intrusions of older complexes are composed of rock series from dunite to gabbro and anorthosites (Monchegorsk complex and from orthopyroxenite to gabbro and anorthosites (Fedorovo-Pansky complex. Some intrusions of this complexes reveal features of multiphase ones. The younger Imandra complex intrusions (about 2.45 Ga are stratified from orthopyroxenite to ferrogabbro. Their important feature is comagmatical connection with volcanites. All the intrusive complexes have the boninite-like mantle origin enriched by lithophyle components. Rocks of these two complexеs with different age have specific geochemical characteristics. In the rocks of the Monchegorsk and Fedorovo-Pansky complexes, the accumulation of REE clearly depends on the basicity of the rocks, the spectrum of REE is non-fractionated and ‘flat’, and the Eu positive anomaly is slightly manifested. In the rocks of the Imandra complex, the level of

  9. Mechanisms and Processes Leading to Reverse Zoning in the Andong Granitoid Pluton, Andong Batholith, Korea

    Institute of Scientific and Technical Information of China (English)

    Sang Koo HWANG

    2002-01-01

    The Andong pluton consists of comagmatic granitoid rocks which constitute outstanding examples of reversely zoned granitoids. The pluton has three lithofacies: hornblende biotite tonalite, biotite granodiorite and porphyritic biotite granite. The zoned pattern forms by locating a tonalite core containing high-temperature mafic assemblages in central part,granodiorite rims in marginal part, and a porphyritic granite cap containing more felsic assemblages in topside of the pluton.Mineral abundances as well as bulk compositions of the granitoids indicate that the interior is enriched in mafic minerals and that it shows higher contents of oxides than the margin and topside. The compositional gradients change gradually with continuity between the lithofacies. The regular compositional variations within the pluton support the argument that the pluton behaved as an individual petrochemical system. Model abundances of the granitoids are in agreement with the bulk compositional gradients, suggesting that no significant interaction with country rocks occurred. Remobilization (resurgence) of deeper parts of the system into the more felsic magmas of the chamber explains the reverse zoning. Fractional crystallization was of importance and probably accounts for the selective removal of the settling phases. The Andong pluton is an example of reversely zoned plutons related by remobilization of more mafic but consanguineous magmas. Large-scale upwelling occurred in the pluton leading to the present arrangement of three lithofacies. It is conceivable that remnants of the reverse zoning become more difficult to discern as the plutonic rocks reach the latest stages of their evolution. In this case, the Andong pluton represents an earlier stage in the evolution of a felsic system that is usually represented by the final stages in normally zoned plutons.

  10. Alkaline battery operational methodology

    Science.gov (United States)

    Sholklapper, Tal; Gallaway, Joshua; Steingart, Daniel; Ingale, Nilesh; Nyce, Michael

    2016-08-16

    Methods of using specific operational charge and discharge parameters to extend the life of alkaline batteries are disclosed. The methods can be used with any commercial primary or secondary alkaline battery, as well as with newer alkaline battery designs, including batteries with flowing electrolyte. The methods include cycling batteries within a narrow operating voltage window, with minimum and maximum cut-off voltages that are set based on battery characteristics and environmental conditions. The narrow voltage window decreases available capacity but allows the batteries to be cycled for hundreds or thousands of times.

  11. Interactions between plutonism and detachments during metamorphic core complex formation, Serifos Island (Cyclades, Greece)

    Science.gov (United States)

    Rabillard, Aurélien; Arbaret, Laurent; Jolivet, Laurent; Le Breton, Nicole; Gumiaux, Charles; Augier, Romain; Grasemann, Bernhard

    2015-06-01

    In order to better understand the interactions between plutonic activity and strain localization during metamorphic core complex formation, the Miocene granodioritic pluton of Serifos (Cyclades, Greece) is studied. This pluton (11.6-9.5 Ma) intruded the Cycladic Blueschists during thinning of the Aegean domain along a system of low-angle normal faults belonging to the south dipping West Cycladic Detachment System (WCDS). Based on structural fieldwork, together with microstructural observations and anisotropy of magnetic susceptibility, we recognize a continuum of deformation from magmatic to brittle conditions within the magmatic body. This succession of deformation events is kinematically compatible with the development of the WCDS. The architecture of the pluton shows a marked asymmetry resulting from its interaction with the detachments. We propose a tectonic scenario for the emplacement of Serifos pluton and its subsequent cooling during the Aegean extension: (1) A first stage corresponds to the metamorphic core complex initiation and associated southwestward shearing along the Meghàlo Livadhi detachment. (2) In the second stage, the Serifos pluton has intruded the dome at shallow crustal level, piercing through the ductile/brittle Meghàlo Livadhi detachment. Southwest directed extensional deformation was contemporaneously transferred upward in the crust along the more localized Kàvos Kiklopas detachment. (3) The third stage was marked by synmagmatic extensional deformation and strain localization at the contact between the pluton and the host rocks resulting in nucleation of narrow shear zones, which (4) continued to develop after the pluton solidification.

  12. Plutons and accretionary episodes of the Klamath Mountains, California and Oregon

    Science.gov (United States)

    Irwin, William P.; Wooden, Joseph L.

    1999-01-01

    The Klamath Mountains consist of various accreted terranes and include many plutons that range in composition from gabbro to granodiorite. Some of the plutons (preaccretionary plutons) were parts of terranes before the terranes accreted; others (accretionary plutons) intruded during or after the accretion of their host terrane(s). This report attempts to (1) graphically illustrate how the Klamath Mountains grew by the accretion of allochthonous oceanic terranes during early Paleozoic to Cretaceous times, (2) identify the plutons as either preaccretionary or accretionary, and (3) genetically relate the plutonic intrusions to specific accretionary episodes. The eight accretionary episodes portrayed in this report are similar to those shown by Irwin and Mankinen (1998) who briefly described the basis for the timing of the episodes and who illustrated the ~110 degrees of clockwise rotation of the Klamath Mountains since Early Devonian time. Each episode is named for the accreting terrane. In all episodes (Figs. 1-8), the heavy black line represents a fault that separates the accreting oceanic rocks on the left from earlier accreted terranes on the right. The preaccretionary plutons are shown within the accreting oceanic crustal rocks to the left of the heavy black line, and the accretionary plutons in most instances are shown intruding previously accreted terranes to the right. Episodes earlier than the Central Metamorphic episode (Fig. 1), and that may have been important in the formation of the early Paleozoic nucleous of the province (the Eastern Klamath terrane), are not known. The 'Present Time' distribution of the accreted terranes and plutons is shown at a large scale in Figure 9. The schematic vertical section (Fig. 10) depicts the terranes as a stack of horizontal slabs that include or are intruded by vertical plutons. Note that at their base the ~170 Ma preaccretionary plutons of the Western Hayfork subterrane are truncated by the ~164 Ma Salt Creek

  13. Three hydroxylated lupeol-based triterpenoid esters isolated from the Eastern Nigeria mistletoe parasitic on Kola acuminata.

    Science.gov (United States)

    Omeje, Edwin Ogechukwu; Osadebe, Patience Ogoamaka; Esimone, Charles Okechukwu; Nworu, Chukwuemeka Sylvester; Kawamura, Akira; Proksch, Peter

    2012-01-01

    Column fractionation and purification of an n-hexane fraction led to the isolation of three lupeol-based triterpenoid esters from the leaves of the Eastern Nigeria mistletoe, Loranthus micranthus Linn parasitic on a local kola nut tree, Kola acuminata. These three compounds were adequately characterised using a combination of UV/visible, IR, NMR (¹³C-NMR and ¹H-NMR), DEPT, MS and two-dimensional correlation (H-H COSY, Hetero-nuclear Single Quantum Correlation (HSQC), HMBC, NOE and NOESY) studies as 7β,15α-dihydroxyl-lup-20(29)-ene-3β-esters of palmitic (I), stearic (II) and eicosanoic acids (III). The characterisation of other isolated compounds is ongoing. Remarkably, this is the first report of the existence of fatty acid esters of an unusual 7β,15α-dihydroxylated lupeol in the Eastern Nigeria mistletoe. These isolated compounds might contribute in part to the numerous established bio-activities of the Eastern Nigeria mistletoes.

  14. Preliminary Results of Marine Electromagnetic Sounding with a Powerful, Remote Source in Kola Bay off the Barents Sea

    Directory of Open Access Journals (Sweden)

    Valery Grigoryev

    2013-01-01

    Full Text Available We present an experiment conducted in Kola Bay off the Barents Sea in which new, six-component electromagnetic seafloor receivers were tested. Signals from a powerful, remote super-long wave (SLW transmitter at several frequencies on the order of tens Hz were recorded at the six sites along a profile across Kola Bay. In spite of the fact that, for technical reasons, not all the components were successfully recorded at every site, the quality of the experimental data was quite satisfactory. The experiment resulted in the successful simulation of an electromagnetic field by the integral equation method. An initial geoelectric model reflecting the main features of the regional geology produced field values that differed greatly from the experimental ones. However, step-by-step modification of the original model considerably improved the fit of the fields. Thereby specific features of the regional geology, in particular the fault tectonics, were able to be corrected. These preliminary results open the possibility of inverse problem solving with more reliable geological conclusions.

  15. Uranium in alkaline rocks

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, M.; Wollenberg, H.; Strisower, B.; Bowman, H.; Flexser, S.; Carmichael, I.

    1978-04-01

    Geologic and geochemical criteria were developed for the occurrence of economic uranium deposits in alkaline igneous rocks. A literature search, a limited chemical analytical program, and visits to three prominent alkaline-rock localities (Ilimaussaq, Greenland; Pocos de Caldas, Brazil; and Powderhorn, Colorado) were made to establish criteria to determine if a site had some uranium resource potential. From the literature, four alkaline-intrusive occurrences of differing character were identified as type-localities for uranium mineralization, and the important aspects of these localities were described. These characteristics were used to categorize and evaluate U.S. occurrences. The literature search disclosed 69 U.S. sites, encompassing nepheline syenite, alkaline granite, and carbonatite. It was possible to compare two-thirds of these sites to the type localities. A ranking system identified ten of the sites as most likely to have uranium resource potential.

  16. A PCR detection method for rapid identification of Melissococcus pluton in honeybee larvae.

    Science.gov (United States)

    Govan, V A; Brözel, V; Allsopp, M H; Davison, S

    1998-05-01

    Melissococcus pluton is the causative agent of European foulbrood, a disease of honeybee larvae. This bacterium is particularly difficult to isolate because of its stringent growth requirements and competition from other bacteria. PCR was used selectively to amplify specific rRNA gene sequences of M. pluton from pure culture, from crude cell lysates, and directly from infected bee larvae. The PCR primers were designed from M. pluton 16S rRNA sequence data. The PCR products were visualized by agarose gel electrophoresis and confirmed as originating from M. pluton by sequencing in both directions. Detection was highly specific, and the probes did not hybridize with DNA from other bacterial species tested. This method enabled the rapid and specific detection and identification of M. pluton from pure cultures and infected bee larvae.

  17. Magma Emplacement and Mafic-Felsic Magma Hybridisation: Structural, Microstructural and Geochemical Evidences From the Pan-African Negash Pluton, Northern Ethiopia

    Science.gov (United States)

    ASRAT, A.; BARBEY, P.; GLEIZES, G.; LUDDEN, J.

    2002-05-01

    The Negash pluton (50 sq. km) consists of late Pan-African, high-K, calc-alkaline granitoids intruded into low-grade metavolcanics and metasediments. This almost circular massif consists of monzogranites, granodiorites, monzodiorites, monzogabbros, and hybrid quartz monzodiorites. The rocks are enriched in LIL-elements, depleted in HFS-elements, have fractionated REE patterns, low 87Sr/86Sri (0.702344 - 0.703553) and 143Nd/144Ndi (0.512031 - 0.512133) ratios, positive ɛ Nd values (3.46 to 5.40), and Pan-African model Nd ages (0.83 to 1.08 Ga). These data, along with single zircon U-Pb dating, show that the pluton was emplaced at 608 Ma from primitive source (underplated material or juvenile island arc crust) with contamination by the country rocks. The pluton shows widespread mafic-felsic magma interactions of two types: (i) homogeneous and heterogeneous hybrid monzodiorites at the northwestern part; and (ii) mingled interfaces at the diorite-granodiorite contact zones in the Eastern and Southeastern parts. Detailed structural (using the method of the anisotropy of magnetic susceptibility) and microstructural studies have been applied to understand how these interactions occurred with respect to pluton construction. The monzodiorites constituting the northwestern part of the pluton, which are composed of complexly zoned plagioclases or unzoned plagioclase laths, euhedral hornblende with biotite cores and acicular apatites, are characterized by abundant net veining, synplutonic dikes, microgranitoid enclaves, and juxtaposed series of discrete mafic-felsic pulses of hybrid nature with vertical syn-emplacement structures. The mingled interfaces between the diorites and granodiorites, on the other hand, are characterized by lobate contacts with interfingering of diorites into granodiorites at the decametric scale, abundant inclined to horizontal granitic pipes, breccia dykes and veins, which are strongly enriched in megacrysts of K-feldspars, and numerous swarms of

  18. Detection of pollution-induced forest decline in the Kola Peninsula using remote sensing and mathematical modelling

    Energy Technology Data Exchange (ETDEWEB)

    Rigina, Olga

    1998-07-01

    Forests on the Kola Peninsula in Northern Russia grow close to the northern tree line. They are subjected to both natural and anthropogenic stress factors. The Cu-Ni smelter 'Severonikel' (Lat. 67 deg 55'N; Long. 32 deg 57'E) near Monchegorsk is one of the two major sources of sulphur dioxide and heavy metals emissions on the Kola Peninsula. These emissions have caused significant deterioration of the surrounding vegetation. The thesis demonstrates how methods of Remote sensing, ground survey and mathematical modelling can be integrated for monitoring of the smelter's environmental impact on the surrounding vegetation: ground truth data are used for calibration of remote-sensed data, which further serve to verify mathematical models. The study aims were: * to estimate the scale of airborne sulphur pollution from the smelting industry on the Kola Peninsula and its effect on vegetation; * to assess spatial extent of the forest decline in the 'Severonikel' smelter impact zone; * to display dynamics of the forest damage area in spatial and temporal perspective; * to validate the Gaussian plume sector model and the IIASA forest impact model as components of the analysis of forest damage. The Regional Acidification Information and Simulation model (RAINS) was applied to calculate sulphur deposition and loads in Fennoscandia in order to assess the contribution of the Kola sources to the deposition pattern in the region. The percentage of the ecosystems where the critical load had been exceeded was calculated. For more detailed assessments, calculations based on local and meso-scale models were made. Landsat-MSS summer images from 1978, 1986 and 1992 and a Landsat -TM image from 1996 were used for change-detection analyses. The methods applied were bandwise histogram matching and subsequent differencing. An unsupervised classification of land-cover was made using the 1996 Landsat-TM image. In situ observations of vegetation type and

  19. Geochemistry and petrogenesis of high-K "sanukitoids" from the Bulai pluton, Central Limpopo Belt, South Africa: Implications for geodynamic changes at the Archaean-Proterozoic boundary

    Science.gov (United States)

    Laurent, Oscar; Martin, Hervé; Doucelance, Régis; Moyen, Jean-François; Paquette, Jean-Louis

    2011-04-01

    The Neoarchaean Bulai pluton is a magmatic complex intrusive in the Central Zone of the Limpopo Belt (Limpopo Province, South Africa). It is made up of large volumes of porphyritic granodiorites with subordinate enclaves and dykes of monzodioritic, enderbitic and granitic compositions. New U-Pb LA-ICP-MS dating on zircon yield pluton-emplacement ages ranging between 2.58 and 2.61 Ga. The whole pluton underwent a high-grade thermal overprint at ~ 2.0 Ga, which did not affect the whole-rock compositions for most of the major and trace-elements, as suggested by a Sm-Nd isochron built up with 16 samples and yielding an age consistent with U-Pb dating. The whole-rock major- and trace-element compositions evidence that the Bulai pluton belongs to a high-K, calc-alkaline to shoshonitic suite, as well as unequivocal affinities with "high-Ti" sanukitoids. Monzodioritic enclaves and enderbites have both "juvenile" affinities and a strongly enriched signature in terms of incompatible trace elements (LREE, HFSE and LILE), pointing to an enriched mantle source. Based on trace-element compositions, we propose the metasomatic agent at their origin to be a melt deriving from terrigenous sediments. We therefore suggest a two-step petrogenetic model for the Bulai pluton: (1) a liquid produced by melting of subducted terrigenous sediments is consumed by reactions with mantle peridotite, producing a metasomatic assemblage; (2) low-degree melting of this metasomatized mantle gives rise to Bulai mafic magmas. Such a model is supported by geochemical modelling and is consistent with previous studies concluding that sanukitoids result from interactions between slab melts and the overlying mantle wedge. Before 2.5 Ga, melting of hydrous subducted metabasalts produced large volumes of TTG (Tonalite-Trondhjemite-Granodiorite) forming most of the volume of Archaean continental crust. By constrast, our geochemical study failed in demonstrating any significant role played by melting of

  20. Magmatic arc construction: Constraints from the structure of the Coast plutonic complex

    Science.gov (United States)

    Andronicos, C. L.

    2007-12-01

    The Coast plutonic complex of British Columbia exposes the middle crust of a vigorous magmatic arc formed in the late Cretaceous and early Cenozoic. The arc is divided into two parts by the crustal scale Coast shear zone. West of the Coast shear zone between Prince Rupert and Douglas Channel plutons were emplaced at pressures between 500 and 850 MPa, are elongate with steeply dipping contacts and have tadpole shaped terminations. The steeply dipping sides of the plutons are concordant with country rock foliations that grade into mylonitic foliations in the cores of transpressive shear zones which strike NW parallel to the arc axis. Field relationships demonstrate that pluton emplacement occurred during displacement on the shear zones, folding of adjacent country rocks and pluton enhanced anatexis of host rocks. Pressure differences in single plutons and across shear zones attests to major vertical displacements during pluton construction. The data indicate that the plutons record emplacement during major transpressive deformation and crustal thickening. The tabular shape of the plutons, their steep dips and concordance with country rock fabric show that pluton emplacement and plate scale deformation were synchronous between ~120 and 85 Ma. East of plutons that intrude the Coast shear zone a sequence of upper amphibolite to granulite facies gneiss and migmatite (central gneiss complex) occurs that host gently dipping tonalite and granodiorite sills. Mineral assemblages in country rocks of the sills track uplift and exhumation from pressures of ~800 MPa to 200 MPa during sill emplacement between ~75 and 50 Ma. The gently to moderately dipping fabrics that host the sills are the result of transposition of an earlier steeply dipping foliation. Sill emplacement occurred during both contractional and extensional deformation as indicated by a reversal in shear from reverse to normal sense observed at a regional scale. The sills are concordant with host rock foliations and

  1. Melt segregation evidence from a young pluton, Takidani Granodiorite (Japan)

    Science.gov (United States)

    Hartung, Eva; Caricchi, Luca; Floess, David; Wallis, Simon; Harayama, Satoru; Chiaradia, Massimo; Kouzmanov, Kalin

    2016-04-01

    We are presenting new petrological data from one of the youngest exposed plutons in the world, the Takidani Granodiorite (Japan), which has been suggested as a source for large volume ignimbrites (> 300km3). Takidani Granodiorite (1.54 Ma ± 0.23 Ma) is located within the active Norikura Volcanic Chain in the Northen Japan Alps and has been previously linked to large andesitic (1.76 Ma ± 0.17 Ma) and rhyolitic eruptions (1.75 Ma ± 0.17 Ma). The pluton is vertically zoned and consists of granites (67 to 68 wt.% SiO2) in the lower section, granodiorites (65 to 66 wt.% SiO2) in the middle section, a chemically more evolved fine-grained porphyritic unit (67 to 71 wt.% SiO2) near the roof and a marginal granodiorite at the roof (67 to 68 wt.% SiO2). The porphyritic texture of the more evolved unit near the roof indicates rapid crystallisation, which could be the result of the late intrusion of this unit at the roof of the magmatic system. However, no sharp contact is found between the underlying granodiorite and the porphyritic unit. Instead, a gradual change in rock fabric, whole-rock chemistry and mineralogy is observed suggesting that melt was extracted from the granodiorite. Electron microprobe analyses of plagioclases show three main crystal populations (Type I, II and III) with distinct anorthite and Fe contents. Type I plagioclase (An30-40) occurs dominantly within the marginal granodiorite at the roof. Type II plagioclase (An40-45) are common in the granodiorite and porphyritic unit. Type III plagioclase (An45-50) is predominantly present in the granite. All plagioclase populations share a common sodic rim (An22) across the different units. Takidani Granodiorite rocks are compared to crystallisation experiments from similar magmatic suites. Emplacement conditions of the Takidani Granodiorite are obtained from the latter as well as barometry, thermometry and hygrometry indicating that magmas were ultimately emplaced at around 200 MPa, 850° C to 875° C and

  2. [Impact of industrial pollution on emission of carbon dioxide by soils in the Kola Subarctic Region].

    Science.gov (United States)

    Koptsik, G N; Kadulin, M S; Zakharova, A I

    2015-01-01

    Soil emission of carbon dioxide, the key component of carbon cycle and the characteristic of soil biological activity, has been studied in background and polluted ecosystems in the Kola subarctic, the large industrial region of Russia. Long-term air pollution by emissions of "Pechenganikel" smelter, the largest source of sulphur dioxide and heavy metals in Northern Europe, has caused the technogenic digression of forest ecosystems. As a result of the digression, the tree layer was destructed, the number of plant species was diminished, the activity of soil biota was weakened, the soils were polluted and exhausted, biogeochemical cycles of elements were disturbed and productivity of ecosystems shrunk. Field investigations revealed the decrease of the in.situ soil respiration in average from 190-230 mg C-CO2/m2 x per h in background pine forests to 130-160, 100, and 20 mg C-CO2/m2.per h at the stages of pine defoliation, sparse pine forest and technogenic barrens of the technogenic succession, respectively. The soil respira- tion in birch forests was more intense than in pine forests and tended to decrease from about 290 mg C-CO2/m2 x per h in background forests to 210-220 and 170-190 mg C-CO2/m2 x per h in defoliating forests and technogenic sparse forests, respectively. Due to high spatial variability of soil respiration in both pine and birch forests significant differences from the background level were found only in technogenic sparse forests and barrens. Soil respiration represents total production of carbon dioxide by plant roots and soil microorganisms. The decrease in share of root respiration in the total soil respiration with the rise of pollution from 38-57% in background forests up to zero in technogenic barrens has been revealed for the first time for this region. This indicates that plants seem to be more sensitive to pollution as compared to relatively resistant microorganisms. Soil respiration and the contribution of roots to the total respiration

  3. Precise Dating and Geological Significance of the Caledonian Shangyou Pluton in South Jiangxi Province

    Institute of Scientific and Technical Information of China (English)

    MAO Jianren; ZENG Qingtao; LI Zilong; HU Qing; ZHAO Xilin; YE Haimin

    2008-01-01

    The zircon SHRIMP dating age for the Shangyou granites is 464+11 Ma. The geological feature of the pluton is consistent with the isotopic age, which shows that it is a product of Caledonian orogenesis. The Shangyou granites are regarded as peraluminous crust-derived granites to possess the typical geochemical characteristics of calc-alkaline rocks on the active continental margin with enriched Si, K, AI (A/CNK = 1.11 on average), HREE, Rb, U, Th and heavily depleted V, Cr, Co, Ni, as well as Ti-Y, Nb-Ta, Zr, St, P and Ba, to be commonly corundum normative (av C = 1.44). The Shangyou granites with higher 87Sr/86Sr ratios (0.707126-0.712186),εNd(t) values (-7.29 to-10.22) and (tDM) values (1.52-1.63 Ga), which are considered to result from partial melting of continental crust metamorphic sedimentary rocks with relatively low of crust maturation degree corresponding to the Middle Proterozoic, to have some possible contributions of mantle-derived components. The Shangyou granites are regarded as post-collision granites, which were formed in a transitional tectonic setting from compression to extension in the Middle Ordovician period after the Yangtze plate was subducted beneath the Cathaysian plate. The Ar-Ar total ages of K-feldspar and biotite are 292.1 Ma and 295.5 Ma respectively, which have recorded information of a late-stage thermal alteration event.

  4. Why are plutons dry? Outgassing mechanisms of crustal magmatic bodies

    Science.gov (United States)

    parmigiani, andrea; Huber, Christian; Bachmann, Olivier; Leclaire, Sébastien

    2016-04-01

    Magma bodies crystallizing to completion within the crust (i.e., forming plutons) typically undergo significant amounts of second boiling (i.e. cooling and crystallization of dominantly anhydrous minerals lead to volatile saturation and bubble nucleation/growth). The low water content ( 6 wt % H2O for evolved compositions in subduction zones), testify that outgassing from crystalline mushy reservoirs must be an efficient and widespread process. Understanding this outgassing mechanism is key to understand how volatiles are transferred from mantle depths to the surface. From the hydrodynamics point of view, the mass balance of exsolved volatiles in these plutonic bodies is controlled by the difference between the rate of degassing (formation of bubbles by 2nd boiling) and outgassing (transport of gas out of the magma body). In this study, we use pore-scale multiphase modeling to constrain these rates as function of the crystal and volatile contents in the magma. Because second boiling is a slow process, one can consider equilibrium degassing as a valid assumption. Outgassing, on the other end, is controlled by the competition between buoyancy, capillary and viscous forces. Our numerical simulations are used to determine the most efficient setting for gas to escape its magmatic trap. The high viscosity of interstitial melts and capillary forces (due to the non-wetting nature of the gas phase with most of the mineral phases in magmatic systems) strongly limits gas transport until vertically extensive gas channels are generated. We show that channels can readily form in volatile-rich coarse-grained mush zones in the upper crust, and allow efficient outgassing at crystallinities around 50-75 vol%, when millimetric bubbles can still win capillary resistive forces.

  5. Cretaceous plutonic rocks in the Donner Lake-Cisco Grove area, northern Sierra Nevada, California

    Science.gov (United States)

    Kulow, Matthew J.; Hanson, Richard E.; Girty, Gary H.; Girty, Melissa S.; Harwood, David S.

    1998-01-01

    The northernmost occurrences of extensive, glaciated exposures of the Sierra Nevada batholith occur in the Donner Lake-Cisco Grove area of the northern Sierra Nevada. The plutonic rocks in this area, which are termed here the Castle Valley plutonic assemblage, crop out over an area of 225 km2 and for the most part are shown as a single undifferentiated mass on previously published geological maps. In the present work, the plutonic assemblage is divided into eight separate intrusive units or lithodemes, two of which each consist of two separate plutons. Compositions are dominantly granodiorite and tonalite, but diorite and granite form small plutons in places. Spectacular examples of comb layering and orbicular texture occur in the diorites. U-Pb zircon ages have been obtained for all but one of the main units and range from ~120 to 114 Ma, indicating that the entire assemblage was emplaced in a narrow time frame in the Early Cretaceous. This is consistent with abundant field evidence that many of the individual phases were intruded penecontemporaneously. The timing of emplacement correlates with onset of major Cretaceous plutonism in the main part of the Sierra Nevada batholith farther south. The emplacement ages also are similar to isotopic ages for gold-quartz mineralization in the Sierran foothills west of the study area, suggesting a direct genetic relationship between the voluminous Early Cretaceous plutonism and hydrothermal gold mineralization.

  6. Natural radioactivity levels in granitic plutons and groundwaters in Southeast part of Eskisehir, Turkey.

    Science.gov (United States)

    Orgün, Y; Altinsoy, N; Gültekin, A H; Karahan, G; Celebi, N

    2005-08-01

    The present work investigated the radioactivity level of the granitoid plutons and its effect on the groundwaters in the southeast part of Eskisehir. Fourteen granitic samples from the Kaymaz and Sivrihisar plutons and 11 groundwater samples from the near vicinity of the pluton were analyzed. The activity concentrations measured for (238)U and (232)Th ranged from 43.59+/-2 to 651.80+/-24 Bq/kg, and 51.16+/-3 to 351.94+/-13 Bq/kg, respectively. The activity concentrations obtained for (40)K varied from 418.50+/-17 to 1618.03+/-66 Bq/kg. The absorbed dose rates in air outdoors ranged from 87.14 to 531.81 nGy/h. All the results obtained from the Kaymaz pluton are higher than those from the Sivrihisar. The U (ave. 16.6 ppm) and Th (ave. 49.9 ppm) values of the Kaymaz pluton are higher than the average concentrations of the magmatic rocks of granitic composition. These results are consistent with high dose rates of the pluton. The gross-alpha activities in the groundwater samples ranged from 0.009 to 1.64 Bq/l and the gross-beta activities from 0.006 to 0.89 Bq/l. The highest gross-alpha value was found in the sample taken from near the Kaymaz pluton. The concentrations of (222)Rn varied from 0.060 to 0.557 Bq/l.

  7. An Archean Geomagnetic Reversal in the Kaap Valley Pluton, South Africa

    Science.gov (United States)

    Layer; Kroner; McWilliams

    1996-08-16

    The Kaap Valley pluton in South Africa is a tonalite intrusion associated with the Archean Barberton Greenstone Belt. Antipodal paleomagnetic directions determined from the central and marginal parts of the pluton record a geomagnetic reversal that occurred as the pluton cooled. The age of the reversal is constrained by an 40Ar/39Ar plateau age from hornblende at 3214 +/- 4 million years, making it the oldest known reversal. The data presented here suggest that Earth has had a reversing, perhaps dipolar, magnetic field since at least 3.2 billion years ago.

  8. Alkaline earth metal thioindates

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov-Ehmin, B.N.; Ivlieva, V.I.; Filatenko, L.A.; Zajtsev, B.E.; Kaziev, G.Z.; Sarabiya, M.G.

    1984-08-01

    Alkaline earth metal thioindates of MIn/sub 2/S/sub 4/ composition were synthesized by interaction of alkaline earth metal oxoindates with hydrogen sulfide during heating. Investigation into the compounds by X-ray analysis showed that calcium compound crystallizes in cubic crystal system and strontium and barium compounds in rhombic crystal system. Lattice parameters and the number of formula units were determined. Thioindates of M/sub 3/In/sub 2/S/sub 6/ composition were synthesized, their individuality was shown.

  9. Forceful Emplacement of Granitic Plutons in an Extensional Tectonic Setting: Syn-kinematic Plutons in the Yagan-Onch Hayrhan Metamorphic Core Complex

    Institute of Scientific and Technical Information of China (English)

    王涛; 郑亚东; 李天兵; 高永军; 马铭波

    2002-01-01

    It is generally considered that granitic plutons are forcefully emplaced in a compressional setting and permissively emplaced in an extensional setting. This paper, however, shows that syn-kinematic (extensional) elliptic granitic plutons in the Yagan-Onch Hayrhan metamorphic core complex (MCC) have relatively strong forceful emplacement, which are indicated by (1) concentric distribution of the rock units, (2) a strain pattern with strong strains on the margins and low strains at the centre of a pluton, and particularly (3) syn-emplacement shortening of the host rocks within the aureole. The strain analysis for the host rocks shows that the host-rock ductile shortening, I.e. Forceful emplacement, provides about 16?24% of the emplacement space for the present plutons. All these suggest that forceful emplacement occurs not only in a compressional tectonic setting, but also in an extensional setting. This study further demonstrates the significance of the multiple emplacement of granitic plutons and provides new information about the causality between granitic magmatism and the formation of the MCC and its dynamics.

  10. Geochemistry and subsequent deformation of the Triassic Longtan pluton in South China: Implications for the origin of the Indosinian tectonomagmatic event

    Science.gov (United States)

    Qiu, L.; Yan, D.; Zhou, M.; Arndt, N.; Tang, S.; Qi, L.

    2012-12-01

    The tectonic configuration of present-day Southeast Asia is the consequence of the amalgamation of microcontinents during the Triassic. The Indosinian tectonic event was recorded by Triassic angular unconformities in Vietnam and South China. Widely distributed Indosinian granitoids and the associated deformation are the key to understanding the tectonic evolution of the region. These granitoids form three tectonomagmatic belts. The Longtan pluton in the northwest belt has a zircon U-Pb age of 218±0.8 Ma, recording the termination of the extensive Indosinian magmatism. This pluton is composed of high-K calc-alkaline granodiorites and granites (64.6-71.8% SiO2 and 3.2-4.7% K2O). The rocks have high initial 87Sr/86Sr (0.7275-0.7468) and negative ɛNd (t) (-11.93 to -9.08), and were crustally derived by melting of Precambrian metasedimentary rocks. Wide spread granitoids in the South China Block have petrological and geochemical features similar to the Longtan pluton and are also considered to have formed in a similar manner. However, there is a younging trend from the southeast belt with ages of 260-240 Ma, to the middle belt at 240-230 Ma and the northwest belt at 230-210 Ma. This younging trend is consistent with EW-trending fold axes in the intruded country rocks, and northward development during the Late Permian to Late Triassic of the assemblage of the tectonic belts and the foreland basins. Therefore, we propose a model involving partial melting of crustal materials to explain the origin of granitoids and progressive northward development of the tectonomagmatic belts. The development of the tectonomagmatic belts was probably linked with the collision between the Indochina and South China Blocks during the Triassic.

  11. Origin of the fluorine-rich highly differentiated granites from the Qianlishan composite plutons (South China) and implications for polymetallic mineralization

    Science.gov (United States)

    Chen, Bin; Ma, Xinghua; Wang, Zhiqiang

    2014-10-01

    Many composite granite plutons occur in South China, accompanied by large-scale polymetallic mineralization. Each composite pluton is composed of main-phase granite and late-stage highly differentiated granite. Traditionally, the highly differentiated granite is thought to be residual melt of the former via fractionation, and ore-forming materials and fluids are from granite magma itself. We propose a different model for the origin of the granites and related mineralization, based on petrological and geochemical studies on the Qianlishan composite plutons that host the supergiant Shizhuyuan W-Sn-Bi-Mo deposit. The main-phase granite shows features of normal granites, while the highly differentiated granite is characterized by F-rich, water-deficient, low fO2, alkalinity, REE tetrad effect, and modified behavior of some trace elements, e.g., very high K/Ba and low K/Rb and Zr/Hf ratios. We suggest that the parent magma of the highly differentiated granite was derived from melting of dominantly lower crustal rocks, triggered by underplating of a new pulse of basaltic magmas; small amounts of basaltic magmas and volatiles such as fluorine were involved in the source of the granite. Addition of fluorine lowered the solidus temperature and viscosity of granite magma, and thus prolonged the process of magma evolution. This resulted in extreme fractional crystallization, and intense interaction between melt and circulating waters from country rocks, forming the unusual geochemical features of the granite. The high temperature circulating waters, along with metamorphic fluids released from deep crustal rocks, subsequently, extract ore-forming metals from country rocks through forming F-bearing complexation, forming the polymetallic deposits.

  12. Central planning, market and subsistence from a tundra perspective: Field experience with reindeer herders in the Kola Peninsula

    Directory of Open Access Journals (Sweden)

    Dessislav Sabev

    2002-04-01

    Full Text Available This paper is based on field experience in the tundra camp of a reindeer-herding brigade with mixed ethnic background (Komi, Sami, Nenets, Russians belonging to the ex-Sovkhoz of Krasnoschelie. Its purpose is to situate the new critical issues facing the reindeer-herding collectives after the economic collapse in Russia in 1998. My main argument is that the increasing economic isolation of the tundra periphery forces the herders to redefine their relationship with both the centre(s and the other tundra actors. Reindeer herding on the Kola Peninsula is analysed in relation to its heterogeneous economic system defined by the old Sovkhoz-like management and the new Western buyer of reindeer meat. Furthermore, the social environment in the herding territories has changed since the deterioration of the central planning economy, implying new renewable resources' users. After massive loss of jobs, militaries, miners and geologists came into the tundra for substantial hunting and fishing and so became actors in the local informal economy. Finally, tundra-located herders and hunters seem to be somewhere unified by a discourse against the town-based administrative power and economic actors such as mining industry. Therefore herders have to deal with both an old administrative system in the agrocentre and new realities in the tundra. Based on a case study of herding/hunting activities in a tundra camp, the paper analyses the social relationships between the different actors in the post-Soviet Kola tundra and express their quest for solutions.

  13. Bullialdus Crater: Excavation and Exposure of an Mg- or Alkali-Suite Pluton?

    Science.gov (United States)

    Klima, R. L.; Cahill, J. T. S.; Hagerty, J.; Lawrence, D.

    2012-07-01

    The reflectance spectra of Bullialdus Crater suggest an enhancement of OH^- relative to the surroundings. We examine local mineralogy and the spatial distribution of local Th and OH^- signatures to investigate the composition of the excavated pluton.

  14. Iron variation within a granitic pluton as determined by near-infrared reflectance

    Science.gov (United States)

    Baird, A. K.

    1984-01-01

    One-hundred fifty-one previously chemically analyzed samples of tonalite from the Lakeview Mountains pluton, southern California batholith, were analyzed for their iron content using near-infrared spectrophotometry. Compared to the earlier analyses of the same sample set by X-ray fluorescence spectrography, the infrared data have higher analytical variance but clearly define patterns of compositional zonation in the pluton which are closely similar to those patterns obtained from X-ray data; petrogenetic interpretations for the pluton would be the same from either data set. Infrared spectral data can be obtained directly in the field with relatively simple instruments and field measurements can be made to average local heterogeneities that often mask significant plutonic variations.

  15. Chronology and cooling history of the Tianmenshan pluton in South Jiangxi Province and their geological significance

    Institute of Scientific and Technical Information of China (English)

    ZENG Qingtao; MAO Jianren; HU Qing; ZHAO Xilin; YE Haimin

    2008-01-01

    Geochronological studies on the crust-derived Tianmenshan pluton were undertaken by SHRIMP zircon U-Pb dating and Ar-Ar dating of biotite, muscovite and K-feldspar, giving a petrogenetic age of 167 Ma. Owing to the closure systems in different minerals, the cooling history of the pluton can be determined with an age-temperature diagram. The late hydrothermal event has been recognized, which is related probably with mineralization. In terms of the comparative geochronological and petrologic records, it is concluded that there are some constrains on tectonic evolution and that the formation of the Tianmenshan pluton proceeded in a transition period from lndosinian post-orogeny extension to strong compressive tectonics. And the timing of the hydrothermal event matches the compressive climax of the Yanshanian orogeny. The temporal gap between granite emplacement and wolframite mineralization could last 10-20 Ma owing to the low cooling rate of the pluton.

  16. Near-roof structure and crack-seal emplacement, Colosseum pluton, Sierra Nevada, California

    Science.gov (United States)

    Bartley, J. M.; Glazner, A. F.; Coleman, D. S.

    2011-12-01

    Field evidence from diverse localities indicates that dike-like granitic plutons are emplaced by magmatic crack-seal, yielding plutons that are essentially huge composite dikes. Plutons that are equant in map view may also form by crack-seal from increments that are subhorizontal and vertically stacked, but field evidence to assess this hypothesis is scarce. Here we present evidence that the Late Cretaceous, granitic Colosseum pluton of Moore (1963), which crops out along the Sierra Nevada crest southwest of Big Pine, California, may have been emplaced as horizontal sheets by crack-seal. The equant outcrop pattern of the elliptical, 2x3 km Colosseum pluton as mapped by Moore (1963) mainly reflects Pleistocene glacial erosion that cut ~600 m down through the pluton's gently sloping roof contact. Moore mapped a steep eastern contact with the Spook pluton, but our field observations suggest that the Spook and Colosseum plutons may be the same. This would imply that the pluton is much larger and that the map pattern is not elliptical. Additionally, the exposed intrusive contact everywhere dips gently, but the eastern intrusive contact has been cut off by the Sierran frontal fault. If so, up to 2.5 km of largely unexplored vertical relief in the pluton is exposed on the eastern escarpment of the Sierra Nevada. Geologic and bulk magnetic susceptibility mapping of near-roof rocks revealed the following. (1) Although the intrusive contact sharply truncates wall-rock foliation, xenoliths are absent, even at contacts, indicating that stoping was an insignificant process. (2) The pluton contains a subhorizontal sheet of leucogranite that is broadly concordant with the roof but bounded both above and below by more typical biotite granodiorite. This sheet may represent one or more intrusive increments. (3) Along the western contact, thin tabular apophyses of the pluton intrude its subvertically layered and foliated roof. Although some of these dip steeply and are concordant

  17. Volcanic-plutonic parity and the differentiation of the continental crust.

    Science.gov (United States)

    Keller, C Brenhin; Schoene, Blair; Barboni, Melanie; Samperton, Kyle M; Husson, Jon M

    2015-07-16

    The continental crust is central to the biological and geological history of Earth. However, crustal heterogeneity has prevented a thorough geochemical comparison of its primary igneous building blocks-volcanic and plutonic rocks-and the processes by which they differentiate to felsic compositions. Our analysis of a comprehensive global data set of volcanic and plutonic whole-rock geochemistry shows that differentiation trends from primitive basaltic to felsic compositions for volcanic versus plutonic samples are generally indistinguishable in subduction-zone settings, but are divergent in continental rifts. Offsets in major- and trace-element differentiation patterns in rift settings suggest higher water content in plutonic magmas and reduced eruptibility of hydrous silicate magmas relative to dry rift volcanics. In both tectonic settings, our results indicate that fractional crystallization, rather than crustal melting, is predominantly responsible for the production of intermediate and felsic magmas, emphasizing the role of mafic cumulates as a residue of crustal differentiation.

  18. Petrology and Geochemistry of Neoproterozoic Arc Plutons Beneath the Atlantic Coastal Plain, SRS, SC

    Energy Technology Data Exchange (ETDEWEB)

    Maryak, M.

    1998-10-21

    In this report is presented first a brief review of the regional geologic setting of the Savannah River Site, descriptions of the plutonic rock units sampled here, whole rock geochemical data on the plutonic igneous rocks, and finally, a discussion of how the crystalline basement rocks of the Savannah River Site formed and how they may correlate with other terranes exposed in the Piedmont of the Carolinas, Georgia, and Virginia.

  19. Thermal modeling of pluton emplacement and associated contact metamorphism:Parashi stock emplacement in the Serranía de Jarara (Alta Guajira, Colombia

    Directory of Open Access Journals (Sweden)

    Zuluaga C. Carlos A.

    2010-12-01

    Full Text Available

    In the northernmost portion of the Serrania de Jarara (Alta Guajira, Colombia, low - medium grade metamorphic rocks from the Etpana Metamorphic Suite were thermally affected by emplacement of a small calc-alkaline intrusion (Parashi Stock. Detailed petrographic analysis in collected rock samples across the NE and NW plutonic contacts show occurrences of textural and mineralogical changes in the country rock fabric that evidence contact metamorphism overprinting regional metamorphism of the Etpana Suite. These changes include growth of andalusite (chiastolite, calcic clinopyroxeneand amphibole porphyroblast crosscutting Sn+1 metamorphicfoliation. Hornblende-plagioclase barometry (ca. 3.1 kbar and cooling models for the stock show maximum time temperature evolution in the country rock at the interpreted depth of intrusion (ca. 11 km and help to evaluate the behavior of the country rock with the changing local geotherm.

  20. An unusually rich scuttle fly fauna (Diptera, Phoridae from north of the Arctic Circle in the Kola Peninsula, N. W. Russia

    Directory of Open Access Journals (Sweden)

    R. Henry Disney

    2013-10-01

    Full Text Available 64 species of Phoridae, in 6 genera, are reported from the Kola Peninsula, north of the Arctic Circle. The new species Megaselia elenae and M. kozlovi are described. 33 species of Megaselia, only known from females, are given code numbers. Keys to the species of all the females of Megaselia and Phora are provided; and also a key to the males European Megaselia species with a notopleural cleft.

  1. The methanol seed extract of Garcinia kola attenuated angiotensin II- and lipopolyssacharide-inducedvascular smooth muscle cell proliferation and nitric oxide production

    Directory of Open Access Journals (Sweden)

    Adeolu A. Adedapo

    2016-10-01

    Full Text Available All over the world, cardiovascular diseases are a risk factor for poor health and early death with predisposing factors to include age, gender, tobacco use, physical inactivity, excessive alcohol consumption, unhealthy diet, obesity, family history of cardiovascular disease, hypertension, diabetes mellitus, hyperlipidemia, psychosocial factors, poverty and low educational status, and air pollution. It is envisaged that herbal products that can stem this trend would be of great benefit. Garcinia kola (GK, also known as bitter kola is one of such plants. Generally used as a social snack and offered to guests in some cultural settings, bitter kola has been indicated in the treatment of laryngitis, general inflammation, bronchitis, viral infections and diabetes. In this study, the effects of methanol seed extract of Garcinia kola on the proliferation of Vascular Smooth Muscle Cells (VSMCs in cell culture by Angiotensin II (Ang II and LPS-induced NO production were carried out. Confluent VSMCs were exposed to GK (25, 50 and 100 μg/ml before or after treatment with lipopolyssacharide (100μg/ml, and Angiotensin II (10-8-10-6M. Cellular proliferation was determined by MTT assay and NO production by Griess assay. Treatment with Angiotensin II (10-8, 10-6 or LPS significantly enhanced proliferation of VSM cells while LPS significantly increased nitric oxide (NO production. Treatment with GK (25, 50 & 100 μg/ml attenuated VSM cell proliferation. The results indicate that GK has potential to inhibit mitogen activated vascular cell growth and possibly inhibit inflammatory responses to LPS. Thus GK may be useful in condition that is characterized by cellular proliferation and inflammatory responses.

  2. Growing season changes in Fennoscandia and Kola peninsula during the period 1982 to 1999 - Implications for reindeer husbandry (In Norwegian with Summary in English)

    OpenAIRE

    Hans Tømmervik; Kjell-Arild Høgda; Jan Åge Riseth; Stein-Rune Karlsen; Frans Emil Wielgolaski

    2005-01-01

    Climate change and particularly variations in air temperature have significant impacts on the growth rhythm of plants where these occur at the limits of their natural distribution range, especially at northern latitudes. Our study area, Fennoscandia and Kola Peninsula, is characterized by large regional climatic differences from south to north, from west to east, and from lowland to mountains. Accordingly, the region is well suited for looking for evidence of climatic change and studying regi...

  3. Alkaline broadening in Stars

    CERN Document Server

    De Kertanguy, A

    2015-01-01

    Giving new insight for line broadening theory for atoms with more structure than hydrogen in most stars. Using symbolic software to build precise wave functions corrected for ds;dp quantum defects. The profiles obtained with that approach, have peculiar trends, narrower than hydrogen, all quantum defects used are taken from atomic database topbase. Illustration of stronger effects of ions and electrons on the alkaline profiles, than neutral-neutral collision mechanism. Keywords : Stars: fundamental parameters - Atomic processes - Line: profiles.

  4. INSTALLATION OF A POST-ACCIDENT CONFINEMENT HIGH-LEVEL RADIATION MONITORING SYSTEM IN THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

    Energy Technology Data Exchange (ETDEWEB)

    GREENE,G.A.; GUPPY,J.G.

    1998-09-01

    This is the final report on the INSP project entitled, ``Post-Accident Confinement High-Level Radiation Monitoring System'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.6 (Attachment 1). This project was initiated in February 1993 to assist the Russians in reducing risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Unit 2, through improved accident detection capability, specifically by the installation of a dual train high-level radiation detection system in the confinement of Unit 2 of the Kola NPP. The major technical objective of this project was to provide, install and make operational the necessary hardware inside the confinement of the Kola NPP Unit 2 to provide early and reliable warning of the release of radionuclides from the reactor into the confinement air space as an indication of the occurrence of a severe accident at the plant. In addition, it was intended to provide hands-on experience and training to the Russian plant workers in the installation, operation, calibration and maintenance of the equipment in order that they may use the equipment without continued US assistance as an effective measure to improve reactor safety at the plant.

  5. Some bioactive potentials of two biflavanols isolated from Garcinia kola on cadmium-induced alterations of raw U937 cells and U937-derived macrophages

    Institute of Scientific and Technical Information of China (English)

    Tebekeme Okoko; Diepreye Ere

    2013-01-01

    Objective: To investigate the abilities of two flavonoids - Garcinia biflavanol-1 (GB-1) and Garcinia biflavanol-2 (GB-2) from Garcinia kola (G. kola) in reducing cadmium-induced effects on raw U937 cells and U937-derived macrophages. Methods: Macrophage U937 cells were incubated with cadmium followed by treatment with the flavonoids and cell viability assessed via trypan blue staining. In the other experiment, the U937 cells were transformed to the macrophage form and treated with cadmium in order to activate them. The cells were later incubated with the flavonoids and finally the supernatant of each cell culture was analysed for the secretion of nitric oxide, catalyse activity, and the release of tumour necrosis factor-alpha, interleukin-1 and interleukin-2 as indices of macrophage activation. Quercetin (a flavonol) was used as the reference flavonoid in all experiments. Results: It revealed that the flavonoids significantly increased the viability of the cells and also reduced the cadmium-induced activation of the macrophage cells in a concentration-dependent manner. The flavanols GB-1 and GB-2 possessed higher activities than quercetin in all cases (P<0.05). Garcinia biflavanol-2 possessed a higher bioactivity than GB-1 significantly (P<0.05). Conclusions: In addition to corroborating the several reported importance of G. kola as a potential neutraceutical and pharmacological condiment, the study also clearly indicates the role hydroxylation especially at the 3´- position of polyphenols could play in enhancing bioactivities of flavonoids.

  6. Experimental Studies for the VVER-440/213 Bubble Condenser System for Kola NPP at the Integral Test Facility BC V-213

    Directory of Open Access Journals (Sweden)

    Vladimir N. Blinkov

    2012-01-01

    Full Text Available In the frame of Tacis Project R2.01/99, which was running from 2003 to 2005, the bubble condenser system of Kola NPP (unit 3 was qualified at the integral test facility BC V-213. Three LB LOCA tests, two MSLB tests, and one SB LOCA test were performed. The appropriate test scenarios for BC V-213 test facility, modeling accidents in the Kola NPP unit 3, were determined with pretest calculations. Analysis of test results has shown that calculated initial conditions and test scenarios were properly reproduced in the tests. The detailed posttest analysis of the tests performed at BC V-213 test facility was aimed to validate the COCOSYS code for the calculation of thermohydraulic processes in the hermetic compartments and bubble condenser. After that the validated COCOSYS code was applied to NPP calculations for Kola NPP (unit 3. Results of Tacis R2.01/99 Project confirmed the bubble condenser functionality during large and small break LOCAs and MSLB accidents. Maximum loads were reached in the LB LOCA case. No condensation oscillations were observed.

  7. Constraints on the depth of generation and emplacement of a magmatic epidote-bearing quartz diorite pluton in the Coast Plutonic Complex, British Columbia

    Science.gov (United States)

    Chang, J.M.; Andronicos, C.L.

    2009-01-01

    Petrology and P-T estimates indicate that a magmatic epidote-bearing quartz diorite pluton from Mt. Gamsby, Coast Plutonic Complex, British Columbia, was sourced at pressures below ???1.4 GPa and cooled nearly isobarically at ???0.9 GPa. The P-T path indicates that the magma was within the stability field of magmatic epidote early and remained there upon final crystallization. The pluton formed and crystallized at depths greater than ???30 km. REE data indicate that garnet was absent in the melting region and did not fractionate during crystallization. This suggests that the crust was less than or equal to ???55 km thick at 188 Ma during the early phases of magmatism in the Coast Plutonic Complex. Late Cretaceous contractional deformation and early Tertiary extension exhumed the rocks to upper crustal levels. Textures of magmatic epidote and other magmatic phases, combined with REE data, can be important for constraining the P-T path followed by magmas. ?? 2009 Blackwell Publishing Ltd.

  8. Is there a geochemical link between volcanic and plutonic rocks in the Organ Mountains caldera?

    Science.gov (United States)

    Memeti, V.; Davidson, J.

    2013-12-01

    Results from separate volcanic and plutonic studies have led to inconsistent conclusions regarding the origins and thus links between volcanic and plutonic systems in continental arcs and the magmatic processes and time scales responsible for their compositional variations. Some have suggested that there is a geochemical and geochronological disconnect between volcanic and plutonic rocks and hence have questioned the existence of magma mush columns beneath active volcanoes. Investigating contemporary volcanic and plutonic rocks that are spatially connected is thus critical in exploring these issues. The ca. 36 Ma Organ Mountains caldera in New Mexico, USA, represents such a system exposing contemporaneous volcanic and plutonic rocks juxtaposed at the surface due to tilting during extensional tectonics along the Rio Grande Rift. Detailed geologic and structural mapping [1] and 40Ar/39Ar ages of both volcanics and plutons [2] demonstrate the spatial and temporal connection of both rock types with active magmatism over >2.5 myr. Three caldera-forming ignimbrites erupted within 600 kyr [2] from this system with a total erupted volume of 500-1,000 km3 as well as less voluminous pre- and post-caldera trachyte and andesite lavas. The ignimbrite sequence ranges from a crystal-poor, high-SiO2 rhyolite at the base to a more crystal-rich, low-SiO2 rhyolite at the top. Compositional zoning with quartz-monzonite at the base grading to syenite and alaskite at the top is also found in the Organ Needle pluton, the main intrusion, which is interpreted to be the source for the ignimbrites [1]. Other contemporaneous and slightly younger plutons have dioritic to leucogranitic compositions. We examined both volcanic and plutonic rocks with petrography and their textural variations with color cathodoluminescence, and used whole rock element and Sr, Nd and Pb isotope geochemistry to constrain magma compositions and origins. Electron microprobe analyses on feldspars have been completed to

  9. Plutons: Simmer between 350° and 500°C for 10 million years, then serve cold (Invited)

    Science.gov (United States)

    Coleman, D. S.; Davis, J.

    2009-12-01

    The growing recognition that continental plutons are assembled incrementally over millions of years requires reexamination of the thermal histories of intrusive rocks. With the exception of the suggestion that pluton magma chambers can be revitalized by mafic input at their deepest structural levels, most aspects of modern pluton petrology are built on the underlying assumption that silicic plutons intrude as discrete thermal packages that undergo subsequent monotonic decay back to a steady-state geothermal gradient. The recognition that homogeneous silicic plutons are constructed over timescales too great to be single events necessitates rethinking pluton intrusion mechanisms, textures, thermochronology, chemical evolution and links to volcanic rocks. Three-dimensional thermal modeling of sheeted (horizontal and vertical) incremental pluton assembly (using HEAT3D by Wohletz, 2007) yields several results that are largely independent of intrusive geometry and may help understand bothersome field and laboratory results from plutonic rocks. 1) All increments cool quickly below hornblende closure temperature. However, late increments are emplaced into walls warmed by earlier increments, and they cycle between hornblende and biotite closure temperatures, a range in which fluid-rich melts are likely to be present. These conditions persist until the increments are far from the region of new magma flux, or the addition of increments stops. These observations are supported by Ar thermochronology and may explain why heterogeneous early marginal intrusive phases often grade into younger homogeneous interior map units. 2) Early increments become the contact metamorphic wall rocks of later increments. This observation suggests that much of the contact metamorphism associated with a given volume of plutonic rock is “lost” via textural modification of early increments during intrusion of later increments. Johnson and Glazner (CMP, in press) argue that mappable variations in

  10. Long-term aerosol and trace gas measurements in Eastern Lapland, Finland: the impact of Kola air pollution to new particle formation and potential CCN

    Science.gov (United States)

    Kyrö, Ella-Maria; Väänänen, Riikka; Kerminen, Veli-Matti; Virkkula, Aki; Asmi, Ari; Nieminen, Tuomo; Dal Maso, Miikka; Petäjä, Tuukka; Keronen, Petri; Aalto, Pasi; Riipinen, Ilona; Lehtipalo, Katrianne; Hari, Pertti; Kulmala, Markku

    2014-05-01

    Sulphur and primary emissions have been decreasing largely all over Europe, resulting in improved air quality and decreased direct radiation forcing by aerosols. The smelter industry in Kola Peninsula is one of largest sources of anthropogenic SO2 within the Arctic domain and since late 1990s the sulphur emissions have been decreasing rapidly (Paatero et al., 2008; Prank et al., 2010). New particle formation (NPF) is tightly linked with the oxidizing product of SO2, namely sulphuric acid (H2SO4), since it is known to be the key component in atmospheric nucleation (Sipilä et al., 2010). Thus, decreasing sulphur pollution may lead to less NPF. However, low values of condensation sink (CS), which is determined by the amount of pre-existing particles, favours NPF. We used 14 years (1998-2011) of aerosol number size distribution and trace gas data from SMEAR I station in Eastern Lapland, Finland, to investigate these relationships between SO2, NPF and CS. The station is a clean background station with occasional sulphur pollution episodes when the air masses arrive over Kola Peninsula. We found that while SO2 decreased by 11.3 % / year, the number of clear NPF event days was also decreasing by 9.9 % / year. At the same time, CS was decreasing also (-8.0 % / year) leading to formation of more particles per single NPF event (J3 increased by 29.7 % / year in 2006-2011) but the low vapour concentrations of H2SO4 (proxy decreased by 6.2 % / year) did not allow them to grow into climatically relevant sizes. Over the time, concentrations of potential CCN (cloud condensing nuclei) were also decreasing with more moderate pace, -4.0 % / year. The events started on average earlier after sunrise when the SO2 concentration during the start of the event was higher and NPF occurred more frequently in air masses which were travelling over Kola. Despite the total decrease in sulphur pollution originating from Kola there is currently no evidence of cleaning of the emissions, rather the

  11. Microstructure and magnetic fabric in the Shuanghe pluton: A synkinematic granite in Eastern Dabie Mountains, China

    Institute of Scientific and Technical Information of China (English)

    YANG; Kunguang; LIU; Qiang; LIU; Yuyan; MA; Changqian; XU

    2004-01-01

    Strain analyses for the Shuanghe pluton show that the main strain planes suffered distinct deformation. The main strain value (XZ) is up to 1.59-2.18, and the value of Flinn index (K) ranges from 0.11 to 0.82. Anisotropy of magnetic susceptibility (AMS) measurements reveal that the orientations of the magnetic foliation and lineation gently dip SE, consistent with the macroscopic foliation of the pluton. The value of anisotropy degree (P) ranges from 1.109 to 1.639, and the shape parameter (7) from 0.079 to 0.534. These studies prove that the pluton was deformed under strong compression. Quartz c-axis textures, defined by monoclinic or triclinic asymmetry, usually developed the high maxima paralleling the b-axis, which is defined by the developed in the high-ultrahigh pressure rocks (UHP) which were captured in the pluton or country rocks. It is concluded that the Shuanghe pluton emplaced under regional compression slightly after the formation of UHP, and it is characterized by synkinematic granitic deformation.

  12. Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

    Institute of Scientific and Technical Information of China (English)

    XIAO Qinghui; LU Xinxiang; WANG Fei; SUN Yangui; WEI Xiangdong; XlNG Zuoyun

    2004-01-01

    The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in China, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is exposed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North China plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±33)Ma at the upper intercept in Concorde diagram represents the age of formation of the pluton,whereas the age of (526 ± 281) Ma at the lower intercept and Ar-Ar mineral dating of hornblende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite provides a petrologic evidence for the timing of cratonization of both the continental crust basement in western China and the basement of the North China plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient China continents had ever happened during the "L(u) liang Movement" between the early Proterozoic and the mid-Proterozoic.

  13. Geochemistry, geochronology and zircon Hf isotopic study of peralkaline-alkaline intrusions along the northern margin of the North China Craton and its tectonic implication for the southeastern Central Asian Orogenic Belt

    Science.gov (United States)

    Zhao, Pan; Jahn, Bor-ming; Xu, Bei; Liao, Wen; Wang, Yanyang

    2016-09-01

    A giant Permian alkaline magmatic belt has recently been identified in southern Inner Mongolia, along the northern margin of the North China Craton (NCC). This belt is mainly composed of syenite, quartz syenite, alkaline granite and mafic microgranular enclaves (MME)-bearing granodiorite. In order to study the petrogenesis and tectonic implications of these rocks, we undertook zircon U-Pb dating and geochemical analysis of two Permian alkaline plutons. The first Guangxingyuan Pluton occurs in the Hexigten area and is composed of MME-bearing tonalite, K-feldspar granite and syenite. The second Durenwuliji Pluton, located in the Xianghuangqi area, comprises syenite, quartz syenite and K-feldspar granite. Zircon U-Pb dating on tonalite, K-feldspar granite, syenite and quartz syenite from the two plutons yielded a tight range of ages from 259 to 267 Ma. The peralkaline-alkaline rocks show high abundance of total alkalis (K2O + Na2O = 7.9-12.9%) and K2O contents (3.9-8.0%), enrichment in large ion lithophile elements (LILE) and light rare earth element (LREE), and depletion of high field strength elements (HFSE). The associated tonalite and MMEs display I-type granitic geochemical affinity, with less total abundance of trace elements than the peralkaline-alkaline rocks. Zircon Hf isotopic analysis of the Guangxingyuan pluton yielded a large range of εHf(t) values from - 15.5 to + 6.7 and model ages (TDMC) from 781 to 2012 Ma. By contrast, the Hf isotopic data of the Durenwuliji pluton shows a small range of εHf(t) from + 6.2 to + 8.9 and TDMC from 667 to 816 Ma. The geochemical and Hf isotopic characteristics indicate that the parental magma was derived from a mixing of metasomatic mantle-derived mafic magma with different amount of crust-derived felsic magma, and followed by fractional crystallization. Considering previous tectonic studies in Inner Mongolia, a Permian post-orogenic extension was proposed to account for these peralkaline-alkaline intrusions following

  14. Electrical Properties of amphiboles from the Kola super deep borehole, Russia, at mantle pressure and temperature conditions

    Science.gov (United States)

    Parthasarathy, G.; Gorbatsevich, Felix

    2012-07-01

    We present here for the first time, the temperature and pressure dependence of the electrical resistivity of ferro-actinolite amphibole from the World's deepest borehole, the Kola super-deep borehole (KSDB) up to the depth of 12.84 km. High-pressure and high-temperature measurements were carried out by using an opposed anvil system up to 700 K and 4 GPa. Ten samples from different depths (from the surface to the deepest 12,890 m) were investigated for their compositional, structural and electrical behaviour. Ferro-actinolite sample exhibits a thermally induced phase transformation to cummingtonite-clinopyroxene—quartz assemblages at 780 K and 0.5 GPa. The transformation temperature is found to be decreasing with the increase of pressure and reaches a value of 680 K at 6.0 GPa. The conductivity activation energy, (determined from the temperature dependence of conductivity) of the ferroactinolite is found to be decreasing from 0.8 eV at 0.5 GPa to 0.30 eV at 6 GPa. The present study indicates that the amphiboles at deeper crustal level is more conducting and bears significance in understanding the physical properties of rocks at the deep continental crust.

  15. Thermochronology of the Cornubian batholith in southwest England: Implications for pluton emplacement and protracted hydrothermal mineralization

    Science.gov (United States)

    Chesley, J.T.; Halliday, A.N.; Snee, L.W.; Mezger, K.; Shepherd, T.J.; Scrivener, R.C.

    1993-01-01

    The metalliferous ore deposits of southwest England are associated with biotite-muscovite granites that intruded upper Paleozoic sediments and volcanic rocks at the end of the Hercynian Orogeny. The hydrothermal mineralization can be subdivided into four stages: 1. (1) exoskarns 2. (2) high-temperature tin and tungsten oxide-bearing sheeted greisen bordered veins and Sn-bearing tourmaline veins and breccias 3. (3) polymetallic quartz-tourmaline-chlorite-sulfide-fluorite-bearing fissure veins, which represent the main episode of economic mineralization 4. (4) late-stage, low-temperature polymetallic fluorite veins. U-Pb dating of monazite and xenotime and 40Ar 39Ar dating of muscovite were used to determine emplacement ages and cooling times for individual plutons within the Cornubian batholith, as well as separate intrusive phases within the plutons. In addition, 40Ar 39Ar ages from hornblende and secondary muscovite and Sm-Nd isochron ages from fluorite were employed to determine the relationship between pluton emplacement and different stages of mineralization. The U-Pb ages indicate that granite magmatism was protracted from ~300 Ma down to ~275 Ma with no evidence of a major hiatus. There is no systematic relation between the age of a pluton and its location within the batholith. The U-Pb ages for separate granite phases within a single pluton are resolvable and indicate that magma emplacement within individual plutons occurred over periods of as much as 4.5 myrs. Felsic porphyry dike emplacement was coeval with plutonism, but continued to ~270 Ma. The geochronologic data suggest that the Cornubian batholith originated from repeated melting events over 30 myrs and was formed by a series of small coalescing granitic bodies. Cooling rates of the main plutons are unrelated to emplacement age, but decrease from the southwest to the northeast from ~210??C myr-1 to ~60??C myr-1 with a mean of 100??C myr-1. These slow cooling rates appear to reflect the addition of

  16. Use of olivine and plagioclase saturation surfaces for the petrogenetic modeling of recrystallized basic plutonic systems

    Science.gov (United States)

    Hanson, G. N.

    1983-01-01

    During petrogenetic studies of basic plutonic rocks, there are at least three major questions to be considered: (1) what were the relative proportions of cumulate crystals and intercumulus melt in a given sample? (2) what is the composition and variation in composition of the melts within the pluton? and (3) what is the original composition of the liquids, their source and evolution prior to the time of emplacement? Use of both saturation surfaces can place strong limits on the compositions of potential cumulate phases and intercumulus melts. Consideration of appropriate trace elements can indicate whether a sample is an orthocumulate, adcumulate or mesocumulate. Thus, when trace element and petrographic data are considered together with the saturation surfaces, it should be possible to begin to answer the three major questions given above, even for strongly recrystallized basic plutons.

  17. An alkaline element

    Energy Technology Data Exchange (ETDEWEB)

    Arita, T.; Murakami, K.; Okha, K.

    1983-04-28

    A cathode with a dual layer active mass is installed in the disk shaped alkaline silver and zinc element. The first layer, which is turned towards the anode, contains 85 parts Ag2O, 5 parts electrolytic MnO2 and 10 parts graphite. The second layer, which contacts the bottom of the element, contains 35 parts Ag2O, 60 parts electrolytic MnO2 and 5 parts graphite. The electrical capacity of the first and second layers is 60 and 40, respectively. The first layer may be discharged with a high current density and the second layer with less current density. The element has high characteristics with comparatively low cost.

  18. Evidence for a close phylogenetic relationship between Melissococcus pluton, the causative agent of European foulbrood disease, and the genus Enterococcus.

    Science.gov (United States)

    Cai, J; Collins, M D

    1994-04-01

    The 16S rRNA gene sequence of Melissococcus pluton, the causative agent of European foulbrood disease, was determined in order to investigate the phylogenetic relationships between this organism and other low-G + C-content gram-positive bacteria. A comparative sequence analysis revealed that M. pluton is a close phylogenetic relative of the genus Enterococcus.

  19. Time span of plutonism, fabric development, and cooling in a Neoproterozoic magmatic arc segment: U Pb age constraints from syn-tectonic plutons, Sark, Channel Islands, UK

    Science.gov (United States)

    Miller, Brent V.; Samson, Scott D.; D'Lemos, Richard S.

    1999-10-01

    New U-Pb zircon and titanite dates from syn-tectonic plutons on the British Channel Island of Sark constrain the time span of plutonism, fabric development, and cooling in this part of the Neoproterozoic Cadomian magmatic arc. The Tintageu leucogneiss is a mylonitic unit that was dated previously at 615.6 +4.2-2.3 Ma. The Port du Moulin quartz diorite, which intruded the Tintageu unit, contains a high-strain solid-state deformation fabric that is less intense than, but parallel to, fabrics in the leucogneiss and yields a U-Pb zircon date of 613.5 +2.3-1.5 Ma. The Little Sark quartz diorite also displays solid-state deformation fabrics in addition to relict magmatic textures, and yields a U-Pb zircon date of 611.4 +2.1-1.3 Ma. The North Sark granodiorite is largely penetratively undeformed, exhibits mainly magmatic fabrics and textures and has a U-Pb zircon date of 608.7 +1.1-1.0 Ma. Two fractions of titanite from each intrusion are essentially concordant and are identical within error, with mean dates of 606.5±0.4 Ma (Port du Moulin quartz diorite), 606.2±0.6 Ma (Little Sark quartz diorite), 606.4±0.6 Ma (North Sark granodiorite). The new U-Pb data, in combination with previous U-Pb and 40Ar/ 39Ar data and previous field studies, confirm the syn-tectonic nature of the Sark plutons and quantify the time span (ca. 7 m.y.) required for intrusion and sufficient crystallization of each body to record incremental strain during waning deformation. Titanite U-Pb and hornblende 40Ar/ 39Ar dates mark final cooling about 2 m.y. after intrusion of the last pluton.

  20. Petrology, geochemistry and thermobarometry of the northern area of the Flamenco pluton, Coastal Range batholith, northern Chile. A thermal approach to the emplacement processes in the Jurassic andean batholiths

    Science.gov (United States)

    Rodríguez, Natalia; Díaz-Alvarado, Juan; Rodríguez, Carmen; Riveros, Karl; Fuentes, Paulina

    2016-04-01

    The Flamenco pluton is part of a N-S alignment of Late Triassic to Early Jurassic intrusive belt comprising the westernmost part of the Coastal Range batholith in northern Chile. The Jurassic-Cretaceous voluminous magmatism related to subduction in the western active continental margin of Gondwana is emplaced in the predominantly metasedimentary Paleozoic host-rocks of the Las Tórtolas formation, which in the northern area of the Flamenco pluton present an intense deformation, including the Chañaral mélange. Geochemically, the Flamenco pluton shows a wide compositional variability (SiO2 between 48wt % and 67wt %). Gabbros, Qtz-diorites and tonalites, mesocratic and leucocratic granodiorites are classified as calc-alkaline, calcic, magnesian and metaluminous magmatism. Flamenco granitoids define cotectic linear evolution trends, typical of magmatic fractionation processes. Geochemical trends are consistent with magmas evolved from undersaturated and low-pressure melts, even though the absence of transitional contacts between intrusive units precludes in-situ fractionation. Although some granodioritic samples show crossed geochemical trends that point to the compositional field of metasediments, and large euhedral prismatic pinnite-biotite crystals, typical Crd pseudomorph, are observed in contact magmatic facies, geochemical assimilation processes are short range, and the occurrence of host-rocks xenoliths is limited to a few meters from the pluton contact. A thermal approach to the emplacement process has been constrained through the thermobarometric results and a 2D thermo-numerical model of the contact aureole. Some Qtz-diorites and granodiorites located in the north area of the pluton exhibit granulitic textures as Hbl-Pl-Qtz triple junctions, poikiloblastic Kfs and Qtz recrystallization. The Hbl-Pl pairs have been used for the thermobarometric study of this metamorphic process, resulting granoblastic equilibrium temperatures between 770 and 790 °C, whereas

  1. SHRIMP zircon U-Pb dating of the Huangfengzhai pluton in eastern Nanling and its geological implications%南岭东段黄峰寨岩体SHRIMP锆石U-Pb年龄及地质意义

    Institute of Scientific and Technical Information of China (English)

    范飞鹏; 肖惠良; 陈乐柱; 蔡逸涛; 李海立; 鲍晓明; 周延

    2016-01-01

    黄峰寨岩体位于南岭钨锡多金属成矿带的东段,对该岩体中的石英二长岩进行 SHRIM P 锆石 U‐Pb 年龄测定、岩石学和地球化学研究。石英二长岩的 SHRIMP 锆石 U‐Pb 年龄为231±3 Ma ,属中三叠世晚期。岩石学和地球化学特征表明,该岩体具有高硅、富铝、高钾、中碱、高钙的特征,属高钾钙碱性系列弱过铝质 S 型花岗岩类;微量元素 Sr 、Ba 、Nb 、P 、Ti 强烈亏损,Rb 、Th 、Ce 、Zr 、Sm 相对富集;稀土元素总量高,轻稀土富集,轻、重稀土分异明显,Eu 中等负异常;Hf(t)为-15.25~-2.88,Hf 两阶段模式年龄值为1.87~2.22Ga ,表明黄峰寨岩体为上地壳底部基性岩部分熔融的产物,推测该岩体可能形成于同碰撞构造环境。%The Huangfengzhai pluton is located in the eastern section of tungsten‐tin polymetallic met‐allogenic belt in the Nanling region .This study carried out SHRIM P zircon U‐Pb dating and lithological and geochemical anlyzses for quartz monazites from the Huangfengzhai pluton .The results show that a zircon U‐Pb age of quartz monzonite from the Huangfengzhai pluton is 231 ± 3 Ma ,belonging to late Mid‐dle Triassic .Lithological ,mineralogical and geochemical analyses suggest that the pluton is rich in Si ,Al and Ca ,with medium alkali ,indicating that the pluton belongs to high‐K ,calc‐alkaline series ,weakly‐per‐luminous S‐type granitoids .The pluton is also depleted in Sr ,Ba ,Nb ,P and Ti ,but relatively enriched in Rb ,Th ,Ce ,Zr and Sm ,with high ΣREE content ,distinct LREE and HREE differentiation ,and weak negative Eu anomalies .Zircon εHf(t) values range from - 15 .25 to - 2 .88 and Hf two‐stage model age values are 1 .87 ~ 2 .22 Ga ,indicating that the Huangfengzhai pluton was derived from partial melting of mafic rocks at the bottom of upper crust .It can be inferred that the Huangfengzhai pluton might form at a

  2. Iron mineralization and associated skarn development around southern contact of the Eğrigöz pluton (northern Menderes Massif-Turkey)

    Science.gov (United States)

    Uǧurcan, Okşan Gökçen; Oyman, Tolga

    2016-11-01

    The Eğrigöz pluton is located in the northern portion of the Menderes Massif, which is the largest known metamorphic core complex that is also characterized by large-scale extension. Kalkan and Karaağıl skarn deposits are located on the southern border of the Eğrigöz Pluton, whereas Katrandağ mineralization developed along the roof pendant. Skarnization in these three areas is associated with the peraluminous, I-type, calc-alkaline, high-K calc-alkaline Eğrigöz Pluton. Geochemical characteristics of the pluton indicate that it was generated in a continental arc setting. Kalkan, Karaağıl, and Katrandağ skarns are hosted in marble bands in two-mica gneiss of the Kalkan Formation, a locally dolomitic and clay-bearing limestone of the Arıkaya Formation and locally dolomitised limestone of the Balıkbaşı Formation, respectively. Skarn development occurred sequentially in two stages, prograde and retrograde. In Kalkan skarn, prograde stage is characterized by clinopyroxene (Di56-73 Hd26-43 Joh1-2), garnet (Adr45-69 Grs30-52 Alm0-1.4 Sps0.7-2.3), amphibole, and magnetite, whereas retrograde stage is dominated by epidote, amphibole, chlorite, quartz, and calcite. In Karaağıl, both calcic and magnesian skarn association occurred as a result of local variations in dolomite content in Arıkaya Formation. The prograde assemblage of magnesian skarn is composed chiefly of spinel, amphibole and olivine. These mineral assemblages were, partially or fully, altered to serpentine, talc, and chlorite during retrograde alteration. Mesh textures of the serpentine indicates that the serpentine was altered from olivine. Olivine was completely destroyed during retrograde alteration without relict grains remaining. Calcic skarn paragenesis include garnet (Grs36-80Adr20-62Alm0-2.2Sps0.2-2.6), clinopyroxene (Di81-92 Hd7-19 Jo0-1), and plagioclase, that belongs to the earlier stage, and amphibole of the retrograde stage. High grossular end member of the garnet probably

  3. Subduction-related Late Carboniferous to Early Permian Magmatism in the Eastern Pontides, the Camlik and Casurluk plutons: Insights from geochemistry, whole-rock Sr-Nd and in situ zircon Lu-Hf isotopes, and U-Pb geochronology

    Science.gov (United States)

    Karsli, Orhan; Dokuz, Abdurrahman; Kandemir, Raif

    2016-12-01

    Late Carboniferous to early Permian granitoid rocks represent a volumetrically minor component of the Eastern Pontide lithosphere, but they preserve useful information about the region's tectonomagmatic history. The Casurluk and Camlik plutons primarily consist of gabbro, gabbroic diorite, diorite, monzogabbro, monzodiorite and monzonite, which intrude early to middle Carboniferous granitic basement rocks in the region. In this study, we use in situ zircon U-Pb ages and Lu-Hf isotopic values, whole-rock Sr-Nd isotopic values, and mineral chemistry and geochemistry of these plutons to determine petrogenesis and crustal evolution; we also discuss geodynamic implications. LA-ICP-MS zircon U-Pb dating of magmatic zircons from the rocks suggests that the plutons were emplaced during the late Carboniferous to early Permian (302 Ma). The metaluminous and I-type intrusive rocks belong to the high-K calc-alkaline series. In addition, they are relatively enriched in light rare earth elements (LREEs) and large-ion lithophile elements (LILEs); they are depleted in heavy rare earth elements (HREEs) and high field strength elements (HFSEs), such as Nb and Ti. All of the samples have homogeneous initial ISr values (0.70675 to 0.70792) and low εNd (t) values (- 5.1 to - 3.3). Zircons from the rocks of both plutons have uniform negative to slightly positive εHf (t) values (- 3.5 to 1.4) and old Hf two-stage model ages (1323 to 1548 Ma), implying that they have the same source, as well as suggesting the involvement of old enriched lithospheric mantle materials during their magma genesis. These results, combined with the εHf (t) values and two-stage model ages, demonstrate that the primary magmas were derived from partial melting of old lithospheric mantle material metasomatized by subduction-related fluids. Considering other regional geological data from the Sakarya Zone where these plutons formed, we conclude that late Carboniferous to early Permian magmatism in the area

  4. Permian High Ba-Sr Granitoids:Geochemistry,Age and Tectonic Implications of Erlangshan Pluton,Urad Zhongqi,Inner Mongolia

    Institute of Scientific and Technical Information of China (English)

    LUO Hongling; WU Tairan; ZHAO Lei; HE Yuankai; JIN Xu

    2009-01-01

    Erlangshan Pluton from Urad Zhongqi.central Inner Mongolia,is located in the middle segment of the northern margin of the North China Plate.The rocks consist mainly of diorites with gneissic structure.Petrochemicai characteristics reveal that the diorites belong to metaluminous,high-potassium calc-alkaline series,with chemical signatures of 1-type granites.They are characterized by low SiO2 contents(56.63%-58.53%)and A/CNK(0.90-0.96),high Al2O3 contents(17.30%-17.96%)and Na2O/K2O ratios(1.20-1.70),enrichment in large ion lithophile elements(LILE,e.g.,Ba=556-915ppm,Sr=463-595 ppm),and relative depletion in high field strength elements(HFSE,e.g.,Nb,Ta,Ti)in primitive mantle-normalized spidergram.and right-declined rare earth element patterns with slightly negative Eu anomalies(δEu=0.72-0.90).They have Sr/Y ratios(20-25)evidently less than Kebu Pluton (49-75)to its east.Sensitive high resolution ion micro-probe U-Pb zircon dating of thediOrites has yieldIed an intrnsive a2e of 270±8 Ma.This leads US to conclude that Erlangshan diorites were formed by mixing between the middle or lower crustal.derived magma and minor mantle-derived mafic magnm,followed by fractional crystallization,which was trigged by crustal extension and fault activity in post-coilisional setting.

  5. Using micro-scale evidence to understand regional-scale hydrothermal alteration of plutonic rocks

    NARCIS (Netherlands)

    Plümper, O.; King, H. E.; Putnis, A.

    2009-01-01

    Subsolidus re-equilibration of plutonic feldspars induced by hydrothermal fluids provides a valuable record of fluid-rock interactions that affect large volumes of the Earth's continental crust (Taylor, 1977). The effect of hydrothermal fluids has important implications for the interpretation of the

  6. The Lac-Croche plutonic complex, Quebec: basement of Grenville paragneisses?

    NARCIS (Netherlands)

    Schrijver, K.

    1969-01-01

    A concordant body of presumably igneous, but deformed and at least partly recrystallized rocks, the Lac-Croche Plutonic Complex, consists of leuconoritic and mangeritic gneisses, and of monzonitic and granitic rocks. It is surrounded by gneisses, at least partly of sedimentary origin. Inclusions of

  7. Thermal modification of hematite-ilmenite intergrowths in the Ecstall pluton, British Columbia, Canada

    DEFF Research Database (Denmark)

    Brownlee, S.J.; Feinberg, J.M.; Harrison, R.J.;

    2010-01-01

    In this study, we examine the effects of reheating on finely exsolved hematite-ilmenite intergrowths from the similar to 91 Ma Ecstall pluton using reflected light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). As a result of the emplacement of the you......In this study, we examine the effects of reheating on finely exsolved hematite-ilmenite intergrowths from the similar to 91 Ma Ecstall pluton using reflected light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). As a result of the emplacement...... of the younger adjacent similar to 52 Ma Quottoon pluton, samples closer to a thermal boundary have experienced greater degrees of thermal alteration. Five main microstructural features characterize hematite-ilmenite intergrowths from the Ecstall: (I) exsolution lamellae of hematite and ilmenite; (II) oxidation....... Higher temperatures also enhanced oxidation in ilmenite. The formation of magnetite altered the bulk magnetic properties of these samples, increasing NRM intensity. This study underscores the need to consider a pluton's post-emplacement thermal history before making tectonic interpretations based...

  8. Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile

    Science.gov (United States)

    Somoza, R.; Tomlinson, A. J.; Zaffarana, C. B.; Singer, S. E.; Puigdomenech Negre, C. G.; Raposo, M. I. B.; Dilles, J. H.

    2015-07-01

    A paleomagnetic and AMS study on Eocene plutonic complexes in the Calama area, northern Chile, reveals high-temperature, high-coercivity magnetizations of dominantly thermoremanent origin and magnetic fabrics controlled by magnetite. The paleomagnetic results indicate that ~ 43 Ma plutons underwent clockwise tectonic rotation, whereas adjacent ~ 39 Ma plutons did not undergo discernible rotation. This points to a middle Eocene age for the younger tectonic rotations associated with the Central Andean Rotation Pattern in the Chuquicamata-Calama area. The petrofabric in these rocks formed under conditions ranging from purely magmatic (i.e. before full crystallization) to low-temperature solid-state deformation. AMS and paleomagnetism suggest that the plutonic bodies were formed by progressive amalgamation of subvertical magma sheets spanning multiple magnetic polarity chrons. The parallelism between magmatic and tectonic foliations suggests that regional tectonic stress controlled ascent, emplacement and rock deformation during cooling. In this context, we suggest that magma ascent and emplacement in the upper crust likely exploited Mesozoic structures which were locally reactivated in the Eocene.

  9. Study of the Emplacement Mechanism of the Fenghuangshan Granite Pluton and Related Cu-Au Mineralization in Tongling, Anhui Province

    Institute of Scientific and Technical Information of China (English)

    WU Ganguo; ZHANG Da; LI Dongxu; ZHANG Xiangxin; SHAO Yongjun; ZANG Wenshuan; WANG Qunfeng

    2004-01-01

    The Fenghuangshan Pluton is located in the Tongling polymineral-cluster district in the middle-lower section of the Yangtze metallogenic belt. In tectonic terms, it is in the middle of the Guichi-Fanchang faulted fold bundle of the lower Yangtze Platform fold belt between the Dabie Orogenic Belt and the Jiangnan Massif. Analyses of the structural deformation characteristics of both the contact zone and the interior of the pluton are used to explain its emplacement mechanism. The foliation and lineation of the pluton, consisting of the oriented distribution of dark minerals and xenoliths, mainly concentrate along the margin of the pluton. Toward the center of the pluton, the foliation structure becomes weak, showing intense compression formation at the margin, and reflecting the conformable intrusion of the pluton. The relatively gentle lineation is evidence of a rotatory emplacement mechanism. Relatively steep marginal foliation reflects compression expanding. Affected by the thermal power of the pluton, the metamorphism of the contact zone has zonation. Both the strike of the axial plane of fold at the contact zone and that of the flow cleavage of the ductile shear zone are consistent with the boundary of the pluton, which reflects the speciality of conformable intrusion. The hinges of the folds are mostly inclined and erect, reflecting both the rotation of the pluton and its upward spiraling emplacement mechanism. Boudins developed in both the contact zone and the steep strata indicate the emplacement characteristic of the ballon expanding. The surrounding rock of the contact zone shortens horizontally. The average percentage of shortening is 39.7%, which further proves the mechanism of the pluton expanding, and the space occupied by the active expanding intrusion was provided by the shortening of the surrounding rock. The left-lateral shear shown by the ductile shear zone and the rheomorphic fold reveals that the pluton emplacement and the deformation of

  10. Alteration of podzolized tills by acid load near Ni-Cu smelters at Monchegorsk, Kola Peninsula, Russia

    Directory of Open Access Journals (Sweden)

    Räisänen, M.L.

    1994-06-01

    Full Text Available Mineralogy and geochemistry of podzolized tills was studied in the area of dieback forest near the Ni-Cu smelters at Monchegorsk, and less extensively forest damage near by Apatity and Kirovsk in the Russian Kola Peninsula. The abundances of main elements (Si, Al, Fe, Mg, Ca, K, Na in the <64 μm fraction were determined by the hot aqua regia digestion method and inductively coupled plasma spectrometry. The clay mineralogy of the silt plus clay fraction was examined by X-ray diffraction after selective extraction and heating treatments. At all study sites, trioctahedral mica and chlorite were totally weathered from the silt and clay fraction (<64 μm of the eluvial layer, leaving behind interstratified mica-vermiculite-smectite clays. In general, the mixed-layer clay of the eluvial layer had low levels of hydroxy interlayering. Illuviated layers were characterized by hydroxy interlayered vermiculite-chlorite. The abundance of chlorite and mica was greater, and the degree of interlayering lower, in parent tills than in the overlying illuviated layers. Regardless of differences in bedrock and till geochemistry, the weathering sequence throughout the podzolized till profile was coherent at most of the sampling sites. Exceptionally, in a few profiles sampled at the totally destroyed forest site, the swelling mixed-layer clay of the eluvial layer displayed a neochloritized structure. On the basis of XRD patterns and geochemistry of the samples, it was inferred that a short-term decomposition of plagioclase had promoted, via inputs of Al-hydroxides, the transformation of mica-vermiculite-smectite to a poorly crystalline interstratification of chlorite-aluminous montmorillonite. The accelerated weathering occurring occasionally in exposed places was probably activated by the strongly acidic load in the vicinity of the smelters and the city of Monchegorsk.

  11. Calculation of elastic properties in lower part of the Kola borehole from bulk chemical compositions of core samples

    Energy Technology Data Exchange (ETDEWEB)

    Babeyko, A.Yu.; Sobolev, S.V. [Shmidt Institute of Physics of the Earth, Moscow (Russian Federation)]|[Univ. of Karlsruhe (Germany); Sinelnikov, E.D. [Shmidt Institute of Physics of the Earth, Moscow (Russian Federation)]|[State Univ. of New York, Stony Brook, NY (United States); Smirnov, Yu.P. [Scientific Center SG-3, Zapoliarniy (Russian Federation); Derevschikova, N.A. [Shmidt Institute of Physics of the Earth, Moscow (Russian Federation)

    1994-09-01

    In-situ elastic properties in deep boreholes are controlled by several factors, mainly by lithology, petrofabric, fluid-filled cracks and pores. In order to separate the effects of different factors it is useful to extract lithology-controlled part from observed in-situ velocities. For that purpose we calculated mineralogical composition and isotropic crack-free elastic properties in the lower part of the Kola borehole from bulk chemical compositions of core samples. We use a new technique of petrophysical modeling based on thermodynamic approach. The reasonable accuracy of the modeling is confirmed by comparison with the observations of mineralogical composition and laboratory measurements of density and elastic wave velocities in upper crustal crystalline rocks at high confining pressure. Calculations were carried out for 896 core samples from the depth segment of 6840-10535m. Using these results we estimate density and crack-free isotropic elastic properties of 554 lithology-defined layers composing this depth segment. Average synthetic P-wave velocity appears to be 2.7% higher than the velocity from Vertical Seismic Profiling (VSP), and 5% higher than sonic log velocity. Average synthetic S-wave velocity is 1.4% higher than that from VSP. These differences can be explained by superposition of effects of fabric-related anisotropy, cracks aligned parallel to the foliation plain, and randomly oriented cracks, with the effects of cracks being the predominant control. Low sonic log velocities are likely caused by drilling-induced cracking (hydrofractures) in the borehole walls. The calculated synthetic density and velocity cross-sections can be used for much more detailed interpretations, for which, however, new, more detailed and reliable seismic data are required.

  12. The origin of spheroidal patterns of weathering in the Pados-Tundra mafic-ultramafic complex, Kola Peninsula, Russia

    Directory of Open Access Journals (Sweden)

    A.Y. Barkov

    2016-12-01

    Full Text Available We document a new and unusual occurrence of patterns of protruding spheroidal weathering developed in a dunitic rock of the Pados-Tundra mafic-ultramafic complex of Early Proterozoic age, Kola Peninsula, Russia. It provides an example similar to that reported recently from a mineralized harzburgite in the Monchepluton layered complex in the same region. These patterns are genetically different from common results of “normal spheroidal weathering” sensu stricto. The spheroidally weathered dunite at Pados-Tundra consists of a high-Fo olivine, Ol (Fo 87. 5, which is, in fact, not altered. Accessory grains of aluminous chromite are present. Relief spheroids (1.5 to 4 cm in diameter; up to ~5 vol. % are distributed sparsely and heterogeneously. They are hosted by the olivine matrix and composed of talc, Tlc, and tremolite, Tr, (Mg# = 95-96 formed presumably at the expense of orthopyroxene, Opx, (i.e., pre-existing oikocrysts during a deuteric (autometasomatic alteration. In contrast, oikocrystic Opx (En 86.0 is quite fresh in related spheroids at Monchepluton, in which only minor deuteric alteration (Tlc + Tr are observed. We infer that (1 the ball-shaped morphology of the weathered surface is a reflection of the presence of oikocrysts of Opx, which crystallized after Ol at the magmatic stage; they were entirely replaced by the deuterically induced Tlc + Tr at Pados-Tundra. (2 Differential rates of weathering are implied for rock-forming minerals in these ultramafic rocks, with a higher resistance of Opx vs. Fo-rich Ol, and Tlc + Tr vs. Fo-rich Ol. (3 The ball-like shape of the large spheroids, produced by magmatic processes, may likely represent an additional factor of their higher stability to weathering in the superficial environment. Similar patterns can be expected in other mafic-ultramafic complexes, especially in layered intrusions.

  13. Formation of the Yandangshan volcanic-plutonic complex (SE China) by melt extraction and crystal accumulation

    Science.gov (United States)

    Yan, Li-Li; He, Zhen-Yu; Jahn, Bor-ming; Zhao, Zhi-Dan

    2016-12-01

    The association of volcanic and shallow plutonic rocks in caldera may provide important clues to the geochemical evolution of silicic magma systems. The Yandangshan caldera is a typical example of late Mesozoic volcanic-plutonic complex in SE China. It is composed of a series of rhyolitic extrusives and subvolcanic intrusions of porphyritic quartz syenites. In this work, we conducted petrological and geochemical studies, as well as zircon dating, on the coexisting volcanic and plutonic rocks from the Yandangshan caldera. The results of SHRIMP and LA-ICP-MS zircon U-Pb dating revealed that the crystallization of the rhyolitic extrusives and subvolcanic intrusions was contemporaneous within analytical errors and in a short period (104-98 Ma). Geochemically, the volcanic rocks are characterized by high Rb/Sr and Rb/Ba ratios and depletion in Ba, Sr, P, Eu and Ti, while the shallow plutons show high K, Ba, Al, Fe and low Rb/Sr and Rb/Ba ratios with insignificant negative Eu anomalies. The volcanic and plutonic rocks have a similar range of zircon Hf isotopic compositions (εHf(t) = - 10.0 to + 1.5) and TDM2 model ages of 2.10-1.23 Ga. They also have comparable whole-rock Sr and Nd isotopic compositions ((87Sr/86Sr)i = 0.7084-0.7090; εNd(t) = - 7.8 to - 6.5) and zircon oxygen isotopic compositions (δ18O mainly = 4.5 to 6.0‰). We argue that the volcanic-plutonic complex of the Yandangshan caldera was formed by reworking of Paleoproterozoic lower crusts in the eastern Cathaysia block, and that the complex could be linked by fractional crystallization and crystal accumulation in a shallow magma chamber. The volcanic rocks represent the highly fractionated end-member, whereas the subvolcanic intrusions of porphyritic quartz syenites could be the residual crystal mushes. This case study could have a general implication for the genetic relationship between volcanic and shallow plutonic rocks in calderas.

  14. Crystal structure of modular sodium-rich and low-iron eudialyte from Lovozero alkaline massif

    Science.gov (United States)

    Rozenberg, K. A.; Rastsvetaeva, R. K.; Aksenov, S. M.

    2016-09-01

    The structure of the sodium-rich representative of the eudialyte group found by A.P. Khomyakov at the Lovozero massif (Kola Peninsula) is studied by X-ray diffraction. The trigonal cell parameters are: a = 14.2032(1) and c = 60.612(1) Å, V = 10589.13 Å3, space group R3m. The structure is refined to the final R = 5.0% in the anisotropic approximation of atomic displacement parameters using 3742|F| > 3σ( F). The idealized formula ( Z = 3) is Na37Ca10Mn2FeZr6Si50(Ti, Nb)2O144(OH)5Cl3 · H2O. Like other 24-layer minerals of the eudialyte group, this mineral has a modular structure. Its structure contains two modules, namely, "alluaivite" (with an admixture of "eudialyte") and "kentbrooksite," called according to the main structural fragments of alluaivite, eudialyte, and kentbrooksite. The mineral found at the Lovozero alkaline massif shows some chemical and symmetry-structural distinctions from the close-in-composition labyrinthite modular mineral from the Khibiny massif. The difference between the minerals stems from different geochemical conditions of mineral formation in the two regions.

  15. Geographically diverse Australian isolates of Melissococcus pluton exhibit minimal genotypic diversity by restriction endonuclease analysis.

    Science.gov (United States)

    Djordjevic, S P; Smith, L A; Forbes, W A; Hornitzky, M A

    1999-04-15

    Melissococcus pluton, the causative agent of European foulbrood is an economically significant disease of honey bees (Apis mellifera) across most regions of the world and is prevalent throughout most states of Australia. 49 Isolates of M. pluton recovered from diseased colonies or honey samples in New South Wales, Queensland, South Australia, Tasmania and Victoria were compared using SDS-PAGE, Western immunoblotting and restriction endonuclease analyses. DNA profiles of all 49 geographically diverse isolates showed remarkably similar AluI profiles although four isolates (one each from Queensland, South Australia, New South Wales and Victoria) displayed minor profile variations compared to AluI patterns of all other isolates. DNA from a subset of the 49 Australian and three isolates from the United Kingdom were digested separately with the restriction endonucleases CfoI, RsaI and DraI. Restriction endonuclease fragment patterns generated using these enzymes were also similar although minor variations were noted. SDS-PAGE of whole cell proteins from 13 of the 49 isolates from different states of Australia, including the four isolates which displayed minor profile variations (AluI) produced indistinguishable patterns. Major immunoreactive proteins of approximate molecular masses of 21, 24, 28, 30, 36, 40, 44, 56, 60, 71, 79 and 95 kDa were observed in immunoblots of whole cell lysates of 22 of the 49 isolates and reacted with rabbit hyperimmune antibodies raised against M. pluton whole cells. Neither SDS-PAGE or immunoblotting was capable of distinguishing differences between geographically diverse isolates of M. pluton. Collectively these data confirm that Australian isolates of M. pluton are genetically homogeneous and that this species may be clonal. Plasmid DNA was not detected in whole cell DNA profiles of any isolate resolved using agarose gel electrophoresis.

  16. Simulation of the atmospheric transport and deposition on a local/meso-and regional scale after hypothetical accidents at the Kola nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Thaning, Lennart; Baklanov, Alexander [Defence Research Establishment, FOA, Division of NBC Defence, Umea (Sweden)

    1997-08-25

    An accident at the Kola nuclear power plant could cause a large release of radioactivity into the atmosphere. To illustrate possible effects on the environment, potential atmospheric transport and deposition are calculated for two different scales - the local/meso- and the regional, using two different models. A 3-dimensional meso-scale model, developed at the Kola Science Centre, and suitable for distances out to a few hundred kilometres, has been used for the local/meso-scale, and a model system based on the MATHEW/ADPIC code, for the regional scale. Some consequences for the population have been estimated by using the MACCS model. Calculated aerial radionuclide activity concentrations, ground contamination and consequences for the population of the Euro-Arctic Barents region are discussed for two scenarios. The results for the local scale show a considerable influence on the radionuclide ground contamination pattern from the presence of precipitation. The significance of wet deposition is confirmed by the results for the regional scale which also emphasise the importance of having access to high quality weather predictions in emergency response organisations. The importance of the specific Arctic nutrition pathways, not included in this study, is discussed. It is important to make further studies in order to investigate the significance of these pathways.

  17. Apatite trace element and halogen compositions as petrogenetic-metallogenic indicators: Examples from four granite plutons in the Sanjiang region, SW China

    Science.gov (United States)

    Pan, Li-Chuan; Hu, Rui-Zhong; Wang, Xin-Song; Bi, Xian-Wu; Zhu, Jing-Jing; Li, Chusi

    2016-06-01

    The abundances of trace elements including Sr, Ga and rare earth elements (REE) and halogens in apatite crystals from four intermediate-felsic plutons in the Zhongdian terrane in the Sanjiang region have been determined using electron microprobe and laser ablation inductively coupled plasma mass spectrometry to evaluate the potential of apatite as a petrogenic-metallogenic indicator. The selected plutons include one that is not mineralized (the Triassic Xiuwacu pluton, or the TXWC pluton), one that hosts a porphyry-type Cu deposit (the Pulang pluton, or the PL pluton), one that hosts a porphyry-type Mo deposit (the Tongchanggou pluton, or the TCG pluton), and one that hosts a vein-type Mo deposit (the Cretaceous Xiuwacu pluton, or the CXWC pluton). Except for the CXWC pluton, the other three plutons have adakite-like trace element signatures in whole rocks. The results from this study show that REE, Sr and halogens in apatite can be used to track magma compositions, oxidation states and crystallization history. Apatite crystals from the adakite-like plutons are characterized by much higher Sr/Y and δEu than the non-adakite-type pluton. This means that apatite, which is not susceptible to alteration, is a useful tool for identifying the adakite-like plutons that no longer preserve the initial Sr/Y ratios in whole rocks due to weathering and hydrothermal alteration. Based on apatite Ga contents and δEu values, it is inferred that the parental magmas for the two adakite-like plutons containing porphyry-type Cu and Mo mineralization are more oxidized than that for the non-adakite-type pluton containing vein-type Mo mineralization. Apatite crystals from the vein-type Mo deposit have much lower Cl/F ratios than those from the porphyry-type Cu and Mo deposits. Apatite crystals from the adakite-like pluton without Cu or Mo mineralization is characterized by much lower Cl/F ratios than those from the adakite-like plutons that host the porphyry-type Cu and Mo deposits. The

  18. Evaluation of phase chemistry and petrochemical aspects of Samchampi–Samteran differentiated alkaline complex of Mikir Hills, northeastern India

    Indian Academy of Sciences (India)

    Abhishek Saha; Sohini Ganguly; Jyotisankar Ray; Nilanjan Chaterjee

    2010-10-01

    The Samchampi –Samteran alkaline complex occurs as a plug-like pluton within the Precambrian granite gneisses of Mikir Hills,Assam,northeastern India and it is genetically related to Sylhet Traps.The intrusive complex is marked by dominant development of syenite within which ijolite – melteigite suite of rocks is emplaced with an arcuate outcrop pattern.Inliers of alkali pyroxenite and alkali gabbro occur within this ijolite –melteigite suite of rocks.The pluton is also traversed by younger intrusives of nepheline syenite and carbonatite.Development of sporadic,lumpy magnetite ore bodies is also recorded within the pluton.Petrographic details of the constituent lithomembers of the pluton have been presented following standard nomenclatorial rules.Overall pyroxene compositions range from diopside to aegirine augite while alkali feldspars are typically orthoclase and plagioclase in syenite corresponds to oligoclase species.Phase chemistry of nepheline is suggestive of Na-rich alkaline character of the complex.Biotite compositions are typically restricted to a uniform compositional range and they belong to ‘biotite ’field in the relevant classification scheme.Garnets (developed in syenite and melteigite)typically tend to be Ti-rich andradite,which on a closer scan can be further designated as melanites.Opaque minerals mostly correspond to magnetite.Use of Lindsley ’s pyroxene thermometric method suggests an equilibration temperature from ∼450°–600°C for melteigite/alkali gabbro and ∼400° C for syenite.Critical assessment of other thermometric methods reveals a temperature of equilibration of ∼700°–1350°C for ijolite –melteigite suite of rocks in contrast to a relatively lower equilibration temperature of ∼600° C for syenite. Geobarometric data based on pyroxene chemistry yield an equilibration pressure of 5.32 –7.72 kb for ijolite,melteigite,alkali pyroxenite,alkali gabbro and nepheline syenite.The dominant syenite member of the

  19. The rapakivi granite plutons of Bodom and Obbnäs, southern Finland: petrography and geochemistry

    Directory of Open Access Journals (Sweden)

    Kosunen, P.

    1999-12-01

    Full Text Available The Obbnäs and Bodom granite plutons of southernmost Finland show the typical petrographic and geochemical features of the Proterozoic rapakivi granites in Finland and elsewhere: they cut sharply across the 1900 Ma Svecofennian metamorphic bedrock and have the geochemical characteristics of subalkaline A-type granites. The Bodom pluton is composed of porphyritic granites (hornblende-, hornblende-biotite-, and biotite-bearing varieties and an even-grained granite that probably represent two separate intrusive phases. This lithologic variation does not occur in the Obbnäs pluton, which is almost entirely composed of porphyritic hornblende-biotite granite that gradually becomes more mafic to the southwest. Three types of hybrid granitoids resulting from magma mingling and mixing occur on the southwestern tip of the Obbnäs peninsula. The Bodom granites are syenogranites, whereas the composition of the Obbnäs granite varies from syeno- to monzogranite. The main silicates of both the Bodom and Obbnäs granites are quartz, microcline, plagioclase (An1541, biotite (siderophyllite, and generally also amphibole (ferropargasite or hastingsite. Plagioclase-mantled alkali feldspar megacrysts are absent or rare. The accessory minerals are fluorite, allanite, zircon, apatite, and iron-titanium oxides; the Obbnäs granite also contains titanite. The Bodom and Obbnäs granites are metaluminous to weakly peraluminous, with average A/CNK of 1.00 and 1.05, respectively, have high Fe/Mg (average FeOtot/[FeOtot+MgO] is 0.94 for the Bodom and 0.87 for the Obbnäs granites, and high Ga/Al (3.78 to 5.22 in Bodom and 2.46 to 4.18 in Obbnäs. The REE contents are high with LREE-enriched chondrite-normalized patterns and moderate (Obbnäs to relatively strong (Bodom negative Eu-anomalies. The Obbnäs granite is enriched in CaO, TiO2, MgO, and FeO, and depleted in SiO2 and K2O compared to the Bodom granites. Also, there are differences in the Ba, Rb, and Sr contents of

  20. Soil organic carbon sequestration as affected by afforestation: the Darab Kola forest (north of Iran) case study.

    Science.gov (United States)

    Kooch, Yahya; Hosseini, Seyed Mohsen; Zaccone, Claudio; Jalilvand, Hamid; Hojjati, Seyed Mohammad

    2012-09-01

    Following the ratification of the Kyoto Protocol, afforestation of formerly arable lands and/or degraded areas has been acknowledged as a land-use change contributing to the mitigation of increasing atmospheric CO(2) concentration in the atmosphere. In the present work, we study the soil organic carbon sequestration (SOCS) in 21 year old stands of maple (Acer velutinum Bioss.), oak (Quercus castaneifolia C.A. Mey.), and red pine (Pinus brutia Ten.) in the Darab Kola region, north of Iran. Soil samples were collected at four different depths (0-10, 10-20, 20-30, and 30-40 cm), and characterized with respect to bulk density, water content, electrical conductivity, pH, texture, lime content, total organic C, total N, and earthworm density and biomass. Data showed that afforested stands significantly affected soil characteristics, also raising SOCS phenomena, with values of 163.3, 120.6, and 102.1 Mg C ha(-1) for red pine, oak and maple stands, respectively, vs. 83.0 Mg C ha(-1) for the control region. Even if the dynamics of organic matter (OM) in soil is very complex and affected by several pedo-climatic factors, a stepwise regression method indicates that SOCS values in the studied area could be predicted using the following parameters, i.e., sand, clay, lime, and total N contents, and C/N ratio. In particular, although the chemical and physical stabilization capacity of organic C by soil is believed to be mainly governed by clay content, regression analysis showed a positive correlation between SOCS and sand (R = 0.86(**)), whereas a negative correlation with clay (R = -0.77(**)) was observed, thus suggesting that most of this organic C occurs as particulate OM instead of mineral-associated OM. Although the proposed models do not take into account possible changes due to natural and anthropogenic processes, they represent a simple way that could be used to evaluate and/or monitor the potential of each forest plantation in immobilizing organic C in soil (thus

  1. Magnetic properties of ilmenite-hematite single crystals from the Ecstall pluton near Prince Rupert, British Columbia

    DEFF Research Database (Denmark)

    Brownlee, Sarah J.; Feinberg, Joshua M.; Kasama, Takeshi

    2011-01-01

    and hematite, the primary paleomagnetic recorder in the Ecstall pluton. Measurements of hysteresis properties, low-temperature remanence, and room temperature isothermal remanent magnetization acquisition and observations from magnetic force microscopy and off-axis electron holography indicate that samples...

  2. SHRIMP U-Pb zircon age of the youngest exposed pluton in eastern China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Analysis using the Sensitive High Resolution Ion Microprobe (SHRIMP) shows that the Yongsheng pluton, located to the south of Huadian County, Jilin Province, in the North China Craton, has a zircon U-Pb isotopic emplacement age of (31.6±13) Ma. It is therefore the youngest exposed pluton so far recognized in eastern China. Although geochemical data indicate intensive crystal fractionation, the Sr-Nd isotopic features suggest that the magmatic source region of the lithospheric mantle was weakly depleted. This implies that the previous enriched lithospheric mantle had been replaced by juvenile asthenospheric mantle before or during the Palaeogene. This recognition has great significance for future work on the Mesozoic-Cenozoic geological evolution and deep geological processes in eastern China.

  3. River Valley pluton, Ontario - A late-Archean/early-Proterozoic anorthositic intrusion in the Grenville Province

    Science.gov (United States)

    Ashwal, Lewis D.; Wooden, Joseph L.

    1989-01-01

    This paper presents Nd, Sr, and Pb isotopic data indicating a late-Archean/early-Proterozoic age for the River Valley anorthositic pluton of the southwestern Grenville Province of Sudbury, Ontario. Pb-Pb isotopic data on 10 whole-rock samples ranging in composition from anorthosite to gabbro yield an age of 2560 + or - 155 Ma. The River Valley pluton is thus the oldest anorthositic intrusive yet recognized within the Grenville Province. The Sm-Nd isotopic system records an age of 2377 + or - 68 Ma. High Pb-208/Pb-204 of deformed samples relative to igneous-textured rocks implies Th introduction and/or U loss during metamorphism in the River Valley area. Rb-Sr data from igneous-textured and deformed samples and from mineral separates give an age of 2185 + or - 105 Ma, indicating substantial disturbance of the Rb-Sr isotopic system.

  4. Timing and nature of tertiary plutonism and extension in the Grouse Creek Mountains, Utah

    Science.gov (United States)

    Egger, A.E.; Dumitru, T.A.; Miller, E.L.; Savage, C.F.I.; Wooden, J.L.

    2003-01-01

    The Grouse Creek-Albion-Raft River metamorphic core complex in northwestern Utah and southern Idaho is characterized by several Tertiary plutons with a range of ages and crosscutting relations that help constrain the timing of extensional deformation. In the Grouse Creek Mountains, at least three distinct, superimposed, extension-related Tertiary deformational events are bracketed by intrusive rocks, followed by a fourth event: motion on range-bounding faults. The Emigrant Pass plutonic complex was emplaced at depths of less than 10 km into Permianage rocks. SHRIMP U-Pb zircon analysis indicates a three-stage intrusion of the complex at 41.3 ?? 0.3 Ma, 36.1 ?? 0.2 Ma, and 34.3 ?? 0.3 Ma. The two youngest phases represent distinctly younger intrusive event(s) than the oldest phase, separated by more than 5 m.y. The oldest phase cuts several metamorphosed and deformed younger-on-older faults, providing a pre-41 Ma age bracket for oldest extension-related deformation in the region. The youngest phase(s) are interpreted to have been intruded during delelopment of a map-scale. N-S-trending recumbent fold, the Bovine Mountain fold, formed during vertical shortening of roof rocks during intrusion. This second event folded older normal faults that are likely pre-41 Ma. Zircons from the youngest part of the pluton show inheritance from Archean basement (???2.5 Ga) and from its Proterozoic sedimentary cover (???1.65 Ga). The Red Butte pluton, emplaced at 15-20 km depth, intruded highly metamorphosed Archean orthogneiss at 25.3 ?? 0.5 Ma; cores of some zircons yield latest Archean ages of 2.55 Ga. The pluton is interpreted to have been intruded during a third deformational and metamorphic event that resulted in vertical flattening fabrics formed during NW to EW stretching, ultimately leading to thinning of cover and top-to-the west motion on the Ingham Pass fault. The Ingham Pass fault represents an important structure in the Grouse Creek Mountains, as it juxtaposes two parts

  5. Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, a new mineral from nepheline syenite pegmatite in the Sakharjok massif, Kola Peninsula, Russia

    Science.gov (United States)

    Lyalina, L. M.; Zolotarev, A. A.; Selivanova, E. A.; Savchenko, Ye. E.; Krivovichev, S. V.; Mikhailova, Yu. A.; Kadyrova, G. I.; Zozulya, D. R.

    2016-12-01

    Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, is a new mineral found in nepheline syenite pegmatite in the Sakharjok alkaline massif, Western Keivy, Kola Peninsula, Russia. The pegmatite mainly consists of nepheline, albite, alkali pyroxenes, amphiboles, biotite and zeolites. Batievaite-(Y) is a late-pegmatitic or hydrothermal mineral associated with meliphanite, fluorite, calcite, zircon, britholite-group minerals, leucophanite, gadolinite-subgroup minerals, titanite, smectites, pyrochlore-group minerals, zirkelite, cerianite-(Ce), rutile, behoite, ilmenite, apatite-group minerals, mimetite, molybdenite, and nickeline. Batievaite-(Y) is pale-cream coloured with white streak and dull, greasy or pearly luster. Its Mohs hardness is 5-5.5. No cleavage or parting was observed. The measured density is 3.45(5) g/cm3. Batievaite-(Y) is optically biaxial positive, α 1.745(5), β 1.747(5), γ 1.752(5) (λ 589 nm), 2 V meas. = 60(5)°, 2 V calc. = 65°. Batievaite-(Y) is triclinic, space group P-1, a 9.4024(8), b 5.5623(5), c 7.3784(6) Å, α 89.919(2), β 101.408(2), γ 96.621(2)°, V 375.65(6) Å3 and Z = 1. The eight strongest lines of the X-ray powder diffraction pattern [ d(Å)(I)( hkl)] are: 2.991(100)(11-2), 7.238(36)(00-1), 3.061(30)(300), 4.350(23)(0-1-1), 9.145(17)(100), 4.042(16)(11-1), 2.819(16)(3-10), 3.745(13)(2-10). The chemical composition determined by electron probe microanalysis (EPMA) is (wt.%): Nb2O5 2.25, TiO2 8.01, ZrO2 2.72, SiO2 29.96, Al2O3 0.56, Fe2O3 0.43, Y2O3 11.45, La2O3 0.22, Ce2O3 0.33, Nd2O3 0.02, Gd2O3 0.07, Dy2O3 0.47, Er2O3 1.07, Tm2O3 0.25, Yb2O3 2.81, Lu2O3 0.45, CaO 24.98, MnO 1.31, MgO 0.01, Na2O 1.13, K2O 0.02, F 2.88, Cl 0.19, H2O 6.75 (determined on the basis of crystal structure data), O = (F,Cl) -1.25, total 97.09 wt.%. The empirical formula based on the EPMA and single-crystal structure analyses is (Y0.81Ca0.65Mn0.15Zr0.12Yb0.11Er0.04Fe3+ 0.04Ce0.02Dy0.02Lu0.02La0.01Tm0.01)Σ2.00((H2O)0.75Ca0.70□0.55)Σ2.00Ca2.00(□0.61Na0

  6. Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, a new mineral from nepheline syenite pegmatite in the Sakharjok massif, Kola Peninsula, Russia

    Science.gov (United States)

    Lyalina, L. M.; Zolotarev, A. A.; Selivanova, E. A.; Savchenko, Ye. E.; Krivovichev, S. V.; Mikhailova, Yu. A.; Kadyrova, G. I.; Zozulya, D. R.

    2016-05-01

    Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, is a new mineral found in nepheline syenite pegmatite in the Sakharjok alkaline massif, Western Keivy, Kola Peninsula, Russia. The pegmatite mainly consists of nepheline, albite, alkali pyroxenes, amphiboles, biotite and zeolites. Batievaite-(Y) is a late-pegmatitic or hydrothermal mineral associated with meliphanite, fluorite, calcite, zircon, britholite-group minerals, leucophanite, gadolinite-subgroup minerals, titanite, smectites, pyrochlore-group minerals, zirkelite, cerianite-(Ce), rutile, behoite, ilmenite, apatite-group minerals, mimetite, molybdenite, and nickeline. Batievaite-(Y) is pale-cream coloured with white streak and dull, greasy or pearly luster. Its Mohs hardness is 5-5.5. No cleavage or parting was observed. The measured density is 3.45(5) g/cm3. Batievaite-(Y) is optically biaxial positive, α 1.745(5), β 1.747(5), γ 1.752(5) (λ 589 nm), 2V meas. = 60(5)°, 2V calc. = 65°. Batievaite-(Y) is triclinic, space group P-1, a 9.4024(8), b 5.5623(5), c 7.3784(6) Å, α 89.919(2), β 101.408(2), γ 96.621(2)°, V 375.65(6) Å3 and Z = 1. The eight strongest lines of the X-ray powder diffraction pattern [d(Å)(I)(hkl)] are: 2.991(100)(11-2), 7.238(36)(00-1), 3.061(30)(300), 4.350(23)(0-1-1), 9.145(17)(100), 4.042(16)(11-1), 2.819(16)(3-10), 3.745(13)(2-10). The chemical composition determined by electron probe microanalysis (EPMA) is (wt.%): Nb2O5 2.25, TiO2 8.01, ZrO2 2.72, SiO2 29.96, Al2O3 0.56, Fe2O3 0.43, Y2O3 11.45, La2O3 0.22, Ce2O3 0.33, Nd2O3 0.02, Gd2O3 0.07, Dy2O3 0.47, Er2O3 1.07, Tm2O3 0.25, Yb2O3 2.81, Lu2O3 0.45, CaO 24.98, MnO 1.31, MgO 0.01, Na2O 1.13, K2O 0.02, F 2.88, Cl 0.19, H2O 6.75 (determined on the basis of crystal structure data), O = (F,Cl) -1.25, total 97.09 wt.%. The empirical formula based on the EPMA and single-crystal structure analyses is (Y0.81Ca0.65Mn0.15Zr0.12Yb0.11Er0.04Fe3+ 0.04Ce0.02Dy0.02Lu0.02La0.01Tm0.01)Σ2.00((H2O)0.75Ca0.70□0.55)Σ2.00Ca2.00(□0.61Na0.25( H2O

  7. Erupted frothy xenoliths may explain lack of country-rock fragments in plutons

    Science.gov (United States)

    Burchardt, Steffi; Troll, Valentin R.; Schmeling, Harro; Koyi, Hemin; Blythe, Lara

    2016-11-01

    Magmatic stoping is discussed to be a main mechanism of magma emplacement. As a consequence of stoping, abundant country-rock fragments should occur within, and at the bottom of, magma reservoirs as “xenolith graveyards”, or become assimilated. However, the common absence of sufficient amounts of both xenoliths and crustal contamination have led to intense controversy about the efficiency of stoping. Here, we present new evidence that may explain the absence of abundant country-rock fragments in plutons. We report on vesiculated crustal xenoliths in volcanic rocks that experienced devolatilisation during heating and partial melting when entrained in magma. We hypothesise that the consequential inflation and density decrease of the xenoliths allowed them to rise and become erupted instead of being preserved in the plutonic record. Our thermomechanical simulations of this process demonstrate that early-stage xenolith sinking can be followed by the rise of a heated, partially-molten xenolith towards the top of the reservoir. There, remnants may disintegrate and mix with resident magma or erupt. Shallow-crustal plutons emplaced into hydrous country rocks may therefore not necessarily contain evidence of the true amount of magmatic stoping during their emplacement. Further studies are needed to quantify the importance of frothy xenolith in removing stoped material.

  8. Erupted frothy xenoliths may explain lack of country-rock fragments in plutons.

    Science.gov (United States)

    Burchardt, Steffi; Troll, Valentin R; Schmeling, Harro; Koyi, Hemin; Blythe, Lara

    2016-11-02

    Magmatic stoping is discussed to be a main mechanism of magma emplacement. As a consequence of stoping, abundant country-rock fragments should occur within, and at the bottom of, magma reservoirs as "xenolith graveyards", or become assimilated. However, the common absence of sufficient amounts of both xenoliths and crustal contamination have led to intense controversy about the efficiency of stoping. Here, we present new evidence that may explain the absence of abundant country-rock fragments in plutons. We report on vesiculated crustal xenoliths in volcanic rocks that experienced devolatilisation during heating and partial melting when entrained in magma. We hypothesise that the consequential inflation and density decrease of the xenoliths allowed them to rise and become erupted instead of being preserved in the plutonic record. Our thermomechanical simulations of this process demonstrate that early-stage xenolith sinking can be followed by the rise of a heated, partially-molten xenolith towards the top of the reservoir. There, remnants may disintegrate and mix with resident magma or erupt. Shallow-crustal plutons emplaced into hydrous country rocks may therefore not necessarily contain evidence of the true amount of magmatic stoping during their emplacement. Further studies are needed to quantify the importance of frothy xenolith in removing stoped material.

  9. Two stages of isotopic exchanges experienced by the Ertaibei granite pluton, northern Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    18O/16O and D/H of coexisting feldspar, quartz, and biotite separates of twenty samples collected from the Ertaibei granite pluton, northern Xinjiang, China are determined. It is shown that the Ertaibei pluton experienced two stages of isotopic exchanges. The second stage of 18O/16O and D/H exchanges with meteoric water brought about a marked decrease in the δ18O values of feldspar and biotite from the second group of samples. The D/H of biotite exhibits a higher sensitivity to the meteoric water alteration than its 18O/16O. However, the first stage of 18O/16O exchange with the 18O-rich aqueous fluid derived from the dehydration within the deep crust caused the δ18OQuartz-Feldspar reversal. It is inferred that the dehydration-melting may have been an important mechanism for anatexis. It is shown that the deep fluid encircled the Ertaibei pluton like an envelope which serves as an effective screen to the surface waters.

  10. Two stages of isotopic exchanges experienced by the Ertaibei granite pluton, northern Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    刘伟

    2000-01-01

    18O/16O and D/H of coexisting feldspar, quartz, and biotite separates of twenty samples collected from the Ertaibei granite pluton, northern Xinjiang, China are determined. It is shown that the Ertaibei pluton experienced two stages of isotopic exchanges. The second stage of 18O/16O and D/H exchanges with meteoric water brought about a marked decrease in the δ18O values of feldspar and biotite from the second group of samples. The D/H of biotite exhibits a higher sensitivity to the meteoric water alteration than its 18O/16O. However, the first stage of 18O/16O exchange with the 18O-rich aqueous fluid derived from the dehydration within the deep crust caused the Δ18OQuariz-Feidspar reversal. It is inferred that the dehydration-melting may have been an important mechanism for anatexis. It is shown that the deep fluid encircled the Ertaibei pluton like an envelope which serves as an effective screen to the surface waters.

  11. Early Paleozoic subduction processes of the Paleo-Asian Ocean: Insights from geochronology and geochemistry of Paleozoic plutons in the Alxa Terrane

    Science.gov (United States)

    Liu, Qian; Zhao, Guochun; Sun, Min; Han, Yigui; Eizenhöfer, Paul R.; Hou, Wenzhu; Zhang, Xiaoran; Zhu, Yanlin; Wang, Bo; Liu, Dongxing; Xu, Bing

    2016-10-01

    The Alxa Terrane is situated in a key area between the North China and Tarim cratons. Paleozoic magmatic records in this terrane place important constraints on the subduction processes of the southern Paleo-Asian Ocean. New data of zircon U-Pb ages and whole-rock elemental and isotopic data reveal two groups of intermediate to felsic plutons in the Alxa Terrane. One group consists of diorites and granitoids that were emplaced at ca. 460-440 Ma and characterized by lower Al2O3/TiO2 ratios and higher TiO2 contents, implying high temperature-low pressure crystallization conditions and a shallow source region. The second group is dominated by granitoids aged at ca. 420-407 Ma and displays high Sr and Ba, low Y and high rare earth elements, with very high Sr/Y ratios and mostly positive Eu anomalies. These characteristics imply low temperature-high pressure crystallization conditions and source regions at deep crustal levels where garnet is stable in the residual phase. Both of the two groups are mostly calc-alkaline to high-K calc-alkaline, depleted in Nb, Ta and Ti and enriched in Ba, K and Sr, indicative of an arc affinity most likely related to the southward subduction of the Paleo-Asian Ocean. Zircon εHf(t) and whole-rock εNd(t) values of these magmatic rocks decrease from 458 Ma to 440 Ma and increase from 417 Ma to 407 Ma, whereas whole-rock initial 87Sr/86Sr ratios display an opposite trend. Such an isotopic change suggests a tectonic switch from an advancing to a retreating subduction regime at ~ 407 Ma. Synthesized data from this and previous studies suggest that the 460-400 Ma magmatic arc in the Alxa Terrane represented the western extension of the Paleozoic arc belt on the northern margin of the North China Craton.

  12. Development of modal layering in granites: a case study from the Carna Pluton, Connemara, Ireland

    Science.gov (United States)

    McKenzie, Kirsty; McCarthy, William; Hunt, Emma

    2016-04-01

    Modal layering in igneous rocks uniquely record dynamic processes operating in magma chambers and also host a large proportion of Earth's strategic mineral deposits. This research investigates the origin of biotite modal layering and primary pseudo-sedimentary structures in felsic magmas, by using a combination of Crystal Size Distribution (CSD) analysis and Electron Probe Microanalysis (EPMA) to determine the mechanisms responsible for the development of these structures in the Carna Pluton, Connemara, Ireland. The Carna Pluton is a composite granodiorite intrusion and is one of five plutons comprising the Galway Granite Complex (425 - 380 Ma). Prominent 30 cm thick modal layers are defined by sharp basal contacts to a biotite-rich (20%) granite, which grades upward over 10 cm into biotite-poor, alkali-feldspar megacrystic granite. The layering strikes parallel to, and dips 30-60° N toward the external pluton contact. Pseudo-sedimentary structures (cross-bedding, flame structures, slumping and crystal graded bedding) are observed within these layers. Petrographic observations indicate the layers contain euhedral biotite and fresh undeformed quartz and feldspar. Throughout the pluton, alkali-feldspar phenocrysts define a foliation that is sub-parallel to the strike of biotite modal layers. Together these observations indicate that the intrusion's concentric foliation, biotite layers and associated structures formed in the magmatic state and due to a complex interaction between magma flow and crystallisation processes. Biotite CSDs (>250 crystals per sample) were determined for nine samples across three biotite-rich layers in a single unit. Preliminary CSD results suggest biotite within basal contacts accumulated via fractional crystallisation within an upward-growing crystal pile, likely reflecting the yield strength of the magma as a limiting factor to gravitational settling of biotite. This is supported by the abrupt decrease in mean biotite crystal size across

  13. Evaluation of the dust and methanol extracts of Garcinia kolae for the control of Callosobruchus maculatus (F.) and Sitophilus zeamais (Mots)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Insecticidal effects of different doses of the dust and methanol extracts ofGarcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects; none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C.maculatus by the lowest concentration of methanol extracts ranged from 95%~100% whereas in S. zeamais, the mortality ranged from 87.5%~100% and 70% ~100% in concentrations of 1 g extract+3 ml methanol and 1 g extract+5 ml methanol, respectively,from 24 to 48 h. The least concentration of 1 g extract+15 ml methanol had no significant lethal effect on Sitophilus zeamais.

  14. 2nd Generation Alkaline Electrolysis

    DEFF Research Database (Denmark)

    Yde, Lars; Kjartansdóttir, Cecilia Kristin; Allebrod, Frank;

    This report provides the results of the 2nd Generation Alkaline Electrolysis project which was initiated in 2008. The project has been conducted from 2009-2012 by a consortium comprising Århus University Business and Social Science – Centre for Energy Technologies (CET (former HIRC)), Technical...

  15. Alkaline resistant ceramics; Alkalimotstaandskraftiga keramer

    Energy Technology Data Exchange (ETDEWEB)

    Westberg, Stig-Bjoern [Vattenfall Utveckling AB, Aelvkarleby (Sweden)

    2001-02-01

    Despite durability in several environments, ceramics and refractories can not endure alkaline environments at high temperature. An example of such an environment is when burning biofuel in modern heat and power plants in which the demand for increasing efficiency results in higher combustion temperatures and content of alkaline substances in the flue gas. Some experiences of these environments has been gained from such vastly different equipment as regenerator chambers in the glass industry and MHD-generators. The grains of a ceramic material are usually bonded together by a glassy phase which despite it frequently being a minor constituent render the materials properties and limits its use at elevated temperature. The damage is usually caused by alkaline containing low-melting phases and the decrease of the viscosity of the bonding glass phase which is caused by the alkaline. The surfaces which are exposed to the flue gas in a modern power plant are not only exposed to the high temperature but also a corroding and eroding, particle containing, gas flow of high velocity. The use of conventional refractory products is limited to 1300-1350 deg C. Higher strength and fracture toughness as well as durability against gases, slag and melts at temperatures exceeding 1700 deg C are expected of the materials of the future. Continuous transport of corrosive compounds to the surface and corrosion products from the surface as well as a suitable environment for the corrosion to occur in are prerequisites for extensive corrosion to come about. The highest corrosion rate is therefore found in a temperature interval between the dew point and the melting point of the alkaline-constituent containing compound. It is therefore important that the corrosion resistance is sufficient in the environment in which alkaline containing melts or slag may appear. In environments such as these, even under normal circumstances durable ceramics, such as alumina and silicon carbide, are attacked

  16. Was the Devonian geomagnetic field dipolar or multipolar? Palaeointensity studies of Devonian igneous rocks from the Minusa Basin (Siberia) and the Kola Peninsula dykes, Russia

    Science.gov (United States)

    Shcherbakova, V. V.; Biggin, A. J.; Veselovskiy, R. V.; Shatsillo, A. V.; Hawkins, L.; Shcherbakov, V. P.; Zhidkov, G. V.

    2017-02-01

    Defining variations in the behaviour of the geomagnetic field through geological time is critical to understanding the dynamics of Earth's core and its response to mantle convection and planetary evolution. Furthermore, the question of whether the axial dipole dominance of the recent palaeomagnetic field persists through the whole of Earth's history is fundamental to determining the reliability of palaeogeographic reconstructions and the efficacy of the magnetosphere in shielding Earth from solar wind radiation. Previous palaeomagnetic directional studies have suggested that the palaeofield had a complex configuration in the Devonian period (419-359 Ma). Here we present new palaeointensity determinations from rocks aged between 408 and 375 Ma from the Minusa Basin (southern Siberia), and the Kola Peninsula to investigate the strength of the field during this enigmatic period. Palaeointensity experiments were performed using the thermal Thellier, microwave Thellier, and Wilson methods on 165 specimens from 25 sites. Six out of eight successful sites from the Minusa Basin and all four successful sites from the Kola Peninsula produced extremely low palaeointensities (uniformitarian view of the palaeomagnetic field: field intensities of nearly an order of magnitude lower than Neogene values (except during relatively rare geomagnetic excursions and reversals) together with the widespread appearance of strange directions found in the Devonian suggest that the Earth's field during this time may have had a dominantly multipolar geometry. A persistent, low intensity multipolar magnetic field and associated diminished magnetosphere would increase the impact of solar particles on the Earth's magnetosphere, ionosphere and atmosphere with potential major implications for Earth's climate and biosphere.

  17. Intrusive rocks of the Holden and Lucerne quadrangles, Washington; the relation of depth zones, composition, textures, and emplacement of plutons

    Science.gov (United States)

    Cater, Fred W.

    1982-01-01

    The core of the northern Cascade Range in Washington consists of Precambrian and upper Paleozoic metamorphic rocks cut by numerous plutons, ranging in age from early Triassic to Miocene. The older plutons have been eroded to catazonal depths, whereas subvolcanic rocks are exposed in the youngest plutons. The Holden and Lucerne quadrangles span a -sizeable and representative part of this core. The oldest of the formations mapped in these quadrangles is the Swakane Biotite Gneiss, which was shown on the quadrangle maps as Cretaceous and older in age. The Swakane has yielded a middle Paleozoic metamorphic age, and also contains evidence of zircon inherited from some parent material more than 1,650 m.y. old. In this report, the Swakane is assigned an early Paleozoic or older age. It consists mostly of biotite gneiss, but interlayered with it are scattered layers and lenses of hornblende schist and gneiss, clinozoisite-epidote gneiss, and quartzite. Thickness of the Swakane is many thousands of meters, and the base is not exposed. The biotite gneiss is probably derived from a pile of siliceous volcanic rocks containing scattered sedimentary beds and basalt flows. Overlying the Swakane is a thick sequence of eugeosynclinal upper Paleozoic rocks metamorphosed to amphibolite grade. The sequence includes quartzite and thin layers of marble, hornblende schist and gneiss, graphitic schist, and smaller amounts of schist and gneiss of widely varying compositions. The layers have been tightly and complexly folded, and, in places, probably had been thrust over the overlying Swakane prior to metamorphism. Youngest of the supracrustal rocks in the area are shale, arkosic sandstone, and conglomerate of the Paleocene Swauk Formation. These rocks are preserved in the Chiwaukum graben, a major structural element of the region. Of uncertain age, but possibly as old as any of the intrusive rocks in the area, are small masses of ultramafic rocks, now almost completely altered to

  18. The features of element concentration in natural waters of the Kola North in conditions of environmental contamination

    Science.gov (United States)

    Bazova, Mariya; Moiseenko, Tatyana

    2016-04-01

    The intensive use of fossil fuels and industrial development in last century led to the formation of acid rain and water acidification. The problem of water acidification greatly was denoted in the middle of last century in North America and in Europe as a result of air emissions of acid gases, primarily sulfur dioxide. The process of water acidification due to the interaction of two factors: 1) the high deposition of acidifying substances, taking into account the duration of exposure; 2) the sensitivity of the natural catchment area of geological, landscape, geographic and climatic characteristics (Moiseenko, 2005). The effects of acid rains on metal migration and cycling were discussed in a number of previous studies (Jeffries, 1997; Moiseenko, 1999; Manio, 2001; Moiseenko, Gashkina, 2007). The distribution of elements in water lakes has been mixed and due to the change of geochemical cycles of elements occurring in the catchment area and in water. On the Kola Peninsula as a result of long-term operation of the copper-nickel smelter was the anthropogenic acidification and water pollution metals. Increased contents of elements due to the combined effect of three factors: 1) landscape-geochemical characteristics of watersheds; 2) dispersion with flue emissions; 3) leaching elements and bonding of metals with organic matter, especially in forested watersheds and wetlands. This region is subject to long-term effects of mining and smelting industries, and therefore difficult to find of water bodies, which can serve as a background lakes. It is proved that manmade acid rain lead to leach into the water of a large group of elements entering the water as a result of man-made streams, as well as the elements that consist of the rocks forming the watersheds. In order to identify the relationships between the components of the elemental composition of the water in the lake was made a factor analysis using a computer program «STATISTICA 10". Factor analysis revealed the

  19. Geology, petrology and U-Pb geochronology of Serra da Rajada Granitic Pluton: implications about ediacaran magmatic evolution in NE portion of the Rio Piranhas-Serido Domain (NE of Borborema Province); Geologia, petrologia e geocronologia U-Pb do Pluton Granitico Serra da Rajada: implicacoes sobre a evolucao magmatica ediacarana na porcao do Dominio Rio Piranhas-Serido (NE da Provincia Borborema)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Alan Pereira da; Dantas, Alexandre Ranier, E-mail: alan.costa@cprm.gov.br, E-mail: alexandre.dantas@cprm.gov.br [Servico Geologico do Brasil (CPRM), Natal, RN (Brazil). Nucleo de Apoio de Natal/Superintendencia Regional de Recife; Nascimento, Marcos Antonio Leite do; Galindo, Antonio Carlos, E-mail: marcos@geologia.ufrn.br, E-mail: galindo@geologia.ufrn.br [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Departamento de Geologia

    2015-12-15

    The Ediacaran plutonic activity, related to the Brazilian/Pan-African orogeny, is one of the most important geological features in the Borborema Province, formed by batholiths, stocks and dikes. The Serra da Rajada Granitic Pluton (SRGP), located in the central portion of the Rio Piranhas-Serido Domain, is an example of these bodies. This site is the target of cartographic, petrographic, lithochemical and geochronological studies. Its rocks are described as monzogranites consisting of K-feldspar, plagioclase (oligoclase-An{sub 23-24%}), quartz and biotite (main mafic), having as accessory minerals opaque, titanite, allanite, apatite and zircon. Chlorite, white mica and carbonate are alteration minerals. Lithochemical data from 15 samples show quite evolved rocks (SiO{sub 2} , 69% to 75%), rich in alkalis (Na{sub 2}O + K{sub 2}O ≥ 8.0%), depleted in MgO (≤ 0.45%), CaO (≤ 1.42%) and TiO{sub 2} (≤ 0.36%), and displaying moderate levels of Fe{sub 2}O{sub 3} t (2.16 to 3.53%). These rocks present a transitional nature between metaluminous and peraluminous (predominance of the latter) and have subalkaline/monzonitic affinity (high-K Calc-alkaline). Harker diagrams represent negative correlations in Fe{sub 2}O{sub 3}t, MgO and CaO, indicating fractionation of mafic and plagioclase. The REE spectrum show enrichment of light in relation to heavy REE (LaN/YbN = 23.70 to 10.13), with negative anomaly in Eu (Eu/ Eu* = 0.70 to 10.13) suggesting fractionation or accumulation in the feldspars source (plagioclase). Data integration allows correlating the SRGP rocks with those described as Equigranular high-K Calc-alkaline Suite. The U-Pb geochronology and Sm-Nd isotope dating indicate that the biotite monzogranite have a crystallization age of 557 ± 13 Ma and TDM model age of 2.36 Ga, respectively, and ε{sub Nd} value of - 20.10 for the crystallization age, allowing to infer a crustal source for the magma generated in the Paleoproterozoic age. (author)

  20. New petrographic, geochemical and geochronological data for the Reguengos de Monsaraz pluton (Ossa Morena Zone, SW Iberian Massif, Portugal

    Directory of Open Access Journals (Sweden)

    Antunes, A.

    2010-06-01

    Full Text Available The Reguengos de Monsaraz pluton is a late to post-tectonic Variscan intrusion occurring in the Ossa Morena Zone (Iberian Variscan Chain. The dominant lithological types are tonalites and granodiorites, but the internal area of the massif is composed of gabbro-dioritic rocks. Field evidence shows that the intrusion is heterogeneous at mesoscopic scale suggesting that the emplacement of mafic and felsic magmas was contemporaneous. Petrographic and geochemical studies reveal that the different lithologic types define a continuous sequence with compositions varying from metaluminous to slightly peraluminous and a typical calc-alkaline signature. In Harker variation diagrams, it is possible to observe systematic rectilinear correlations pointing to the involvement of magma mingling/mixing processes in the petrogenesis of this sequence. Rb-Sr isotopic data, using a mineral-mineral pair from a granodiorite sample, yielded an age of 298 Ma, interpreted as a cooling age after igneous crystallization.

    El plutón de Reguengos de Monsaraz es una intrusión varisca tardi- a post- tectónica localizada en la Zona de Ossa Morena (Cadena Varisca Ibérica. Los tipos litológicos dominantes son las tonalitas y las granodioritas aunque la zona mas interna del macizo está formada por rocas gabro-dioríticas. Las evidencias de campo muestran que todos los tipos litológicos son heterogéneos a escala mesoscópica y sugieren que el emplazamiento de los magmas máficos y félsicos fue contemporáneo. Los estudios petrográficos y geoquímicos muestran que los diferentes litotipos definen una secuencia continua con una afinidad calcoalcalina típica y composiciones variando desde metaluminosas a peraluminosas. En los diagramas de Harker se observan correlaciones rectilíneas sistemáticas, lo que sugiere que la mezcla de magmas tuvo un papel decisivo en su petrogénesis. Los datos isotópicos de Rb-Sr, usando un par mineral-mineral de una granodiorita

  1. SHRIMP U-Pb zircon age, geochemistry and Nd isotope of the Guandaoshan pluton in SW Sichuan: Petrogenesis and tectonic significance

    Institute of Scientific and Technical Information of China (English)

    LI; Xianhua(李献华); LI; Zhengxiang(李正祥); ZHOU; Hanwen(周汉文); LIU; Ying(刘颖); LIANG; Xirong(梁细荣); LI; Wuxian(李武显)

    2003-01-01

    SHRIMP U-Pb zircon age, geochemical and Nd isotopic data are reported for the Neoproterozoic Guandaoshan pluton in the Yanbian region, SW Sichuan. This pluton is of typical I-type granite and emplaced at (857±13) Ma. Geochemical and Nd isotopic characters suggest that the pluton was generated by partial melting of pre-existing, young (late Mesoproterozoic to early Neoproterozoic) low-K tholeiitic protolith within an intraplate anorogenic setting. The Guandaoshan pluton probably records the earliest magmatism induced by the proposed ca. 860-750 Ma mantle superplume beneath the supercontinent Rodinia.

  2. Microstructure and magnetic fabric in the Shuanghe pluton:A synkinematic granite in Eastern Dabie Mountains, China

    Institute of Scientific and Technical Information of China (English)

    YANG Kunguang; LIU Qiang; LIU Yuyan; MA Changqian; XU Yajun; YANG Kuifeng

    2004-01-01

    Strain analyses for the Shuanghe pluton show that the main strain planes suffered distinct deformation. The main strain value (XZ) is up to 1.59-2.18, and the value of Flinn index (K) ranges from 0.11 to 0.82. Anisotropy of magnetic susceptibility (AMS) measurements reveal that the orientations of the magnetic foliation and lineation gently dip SE, consistent with the macroscopic foliation of the pluton. The value of anisotropy degree (P) ranges from 1.109 to 1.639, and the shape parameter (7) from 0.079 to 0.534. These studies prove that the pluton was deformed under strong compression. Quartz c-axis textures, defined by monoclinic or triclinic asymmetry, usually developed the high maxima paralleling the b-axis, which is defined by the developed in the high-ultrahigh pressure rocks (UHP) which were captured in the pluton or country rocks. It is concluded that the Shuanghe pluton emplaced under regional compression slightly after the formation of UHP, and it is characterized by synkinematic granitic deformation.

  3. Petrochemistry,Age and Petrogenesis of the Shexian Pluton in Southern Anhui

    Institute of Scientific and Technical Information of China (English)

    邢凤鸣; 任思明; 等

    1991-01-01

    The Shexian gneissic granodiorite in southern Anhui trends NE55°from Shexian in the west to Guitoujian in the east with a length of 22km and an outcrop area of 32km .It was considered formerly to be Caledonian on the basis of a biotite K-Ar age of 474Ma(1982).However,new evi-dence indicates that it may be Early Jinning in age as shown by:(1)it is found intruding into the Mid-Proterozoic Shangxi Group and is unconformably overlain by the Sinian Xiuning Formation,and (2) a zircon U-Th-Pb age of 928 Ma is obtained for the pluton.The pluton is composed of plagioclase(An=27.37%),K-feldspar(14%),biotite(16%) and quartz(32%).Accessory minerals are ilmenite(150g/T),xenotime(15g/T),garnet(25g/T),monazite(10g/T),zircon(20g/T)and apatite(104g/T).Petrochemical characteristics of the intrusion are:(1)Al-enrichment(A/NKC=1.30);(2)H2O enrichment(H2O=1.74%);and (3)low oxidation index(?ˊ=0.10).It belongs to the continental crust transformation type as evidenced by :(1)MF and Mg/Y values of biotite are 0.41 and 0.31 respectively;(2)(87Sr/86Sr)=0.71119;(3)δEu=0.52;and (4)A/NKC=130.The Shexian pluton is therefore considered as a product of melting of phyllite at depth in the light of similarities in trace element and REE contents with the phyllite of the Banxi Group.Calculations of REE batch partial melting indicate that it may have re-sulted from 75% melting of the Banxi phyllite.

  4. Development of alkaline fuel cells.

    Energy Technology Data Exchange (ETDEWEB)

    Hibbs, Michael R.; Jenkins, Janelle E.; Alam, Todd Michael; Janarthanan, Rajeswari; Horan, James L.; Caire, Benjamin R.; Ziegler, Zachary C.; Herring, Andrew M.; Yang, Yuan; Zuo, Xiaobing; Robson, Michael H.; Artyushkova, Kateryna; Patterson, Wendy; Atanassov, Plamen Borissov

    2013-09-01

    This project focuses on the development and demonstration of anion exchange membrane (AEM) fuel cells for portable power applications. Novel polymeric anion exchange membranes and ionomers with high chemical stabilities were prepared characterized by researchers at Sandia National Laboratories. Durable, non-precious metal catalysts were prepared by Dr. Plamen Atanassovs research group at the University of New Mexico by utilizing an aerosol-based process to prepare templated nano-structures. Dr. Andy Herrings group at the Colorado School of Mines combined all of these materials to fabricate and test membrane electrode assemblies for single cell testing in a methanol-fueled alkaline system. The highest power density achieved in this study was 54 mW/cm2 which was 90% of the project target and the highest reported power density for a direct methanol alkaline fuel cell.

  5. Ductile strain rate recorded in the Symvolon syn-extensional plutonic body (Rhodope core complex, Greece)

    Science.gov (United States)

    Cirrincione, Rosolino; Fazio, Eugenio; Ortolano, Gaetano; Fiannacca, Patrizia; Kern, Hartmut; Mengel, Kurt; Pezzino, Antonino; Punturo, Rosalda

    2016-04-01

    The present contribution deals with quantitative microstructural analysis, which was performed on granodiorites of the syn-tectonic Symvolon pluton (Punturo et al., 2014) at the south-western boundary of the Rhodope Core Complex (Greece). Our purpose is the quantification of ductile strain rate achieved across the pluton, by considering its cooling gradient from the centre to the periphery, using the combination of a paleopiezometer (Shimizu, 2008) and a quartz flow law (Hirth et al., 2001). Obtained results, associated with a detailed cooling history (Dinter et al., 1995), allowed us to reconstruct the joined cooling and strain gradient evolution of the pluton from its emplacement during early Miocene (ca. 700°C at 22 Ma) to its following cooling stage (ca. 500-300°C at 15 Ma). Shearing temperature values were constrained by means of a thermodynamic approach based on the recognition of syn-shear assemblages at incremental strain; to this aim, statistical handling of mineral chemistry X-Ray maps was carried out on microdomains detected at the tails of porphyroclasts. Results indicate that the strain/cooling gradients evolve "arm in arm" across the pluton, as also testified by the progressive development of mylonitic fabric over the magmatic microstructures approaching the host rock. References • Dinter, D. A., Macfarlane, A., Hames, W., Isachsen, C., Bowring, S., and Royden, L. (1995). U-Pb and 40Ar/39Ar geochronology of the Symvolon granodiorite: Implications for the thermal and structural evolution of the Rhodope metamorphic core complex, northeastern Greece. Tectonics, 14 (4), 886-908. • Shimizu, I. (2008). Theories and applicability of grain size piezometers: The role of dynamic recrystallization mechanisms. Journal of Structural Geology, 30 (7), 899-917. • Hirth, G., Teyssier, C., and Dunlap, J. W. (2001). An evaluation of quartzite flow laws based on comparisons between experimentally and naturally deformed rocks. International Journal of Earth

  6. Petrology of upper Eocene-Oligocene plutonic rocks of Moalleman Damghan area

    Science.gov (United States)

    Kohansal, Reza; Zolfaghari, Seddigheh; Hashem Emami, Mohammad

    2010-05-01

    The plutonic rocks of this area include cryptodoms, hypoabyssal plutonic bodies and dikes which intruded in to the late Lutetian- late Eocene rocks. The hypoabyssal plutonic rocks in Moalleman are classified in to two main groups: - Acidic rocks, including microgranite to microgranodiorite. - Intermediate rocks, including microquartzmonzodiorite to microquartzdiorite of hypoabyssal type. Presence of fine-grained mafic xenoliths with abundant biotite, amphibole and pyroxene in the intermediate rocks may be considered as an evidence of the role of mantle melting occurrence in the formation of these rocks. Occurrence of a felsitic texture, showing a high differentiation coefficient and existence of large quarts which are embayed, rounded and infiltered by material, and finally turmalinization in the acidic rocks due to Boron metasomatism suggest the role of crust in the formation of afore mentioned rocks as well. In some acidic rocks plagioclases show oscillatory zoning. This phenomenon along with the fact that biotite granites in these rocks crystallized before crystallization of quarts and after crystallization of alkali feldspar suggest that the crystallization of these rocks accomplished in the presence of 2 percent water, pertitic texture in some feldspars of the intermediate rocks this conclusion. Supports on the basis of the geochemical studies most of the hypoabyssal rocks of Moalleman area fall in subalkaline- calcoalkaline fields. Variation of immobile incompatible trace elements versus differentiation coefficient and the situation of samples in winkler diagram show the role of crustal- melting in the formation of acidic rocks. Trace element content of some rocks (e.g. Cu and Sm) with in this group show mantle specification, while some other rocks (e.g. Zr, Th, Hf) show crustal specification. The intermediate rocks of the study area therefore, indicate a hybridization of magmas from both the mantle and crust. Study of the temperature and water vapour

  7. Revisiting the Baja-British Columbia hypothesis: Argon-argon geochronology and paleomagnetism of the Ecstall, Butedale, and Smith Island plutons, British Columbia, Canada

    Science.gov (United States)

    Brownlee, Sarah Jo

    The controversy concerning terrane displacements in western British Columbia, otherwise known as the Baja-BC hypothesis, is revisited using paleomagnetism, rock magnetism, and 40Ar/39Ar geochronology and thermal modeling. We studied three plutons in northwest British Columbia, the Ecstall, Butedale, and Smith Island plutons. The Ecstall pluton is the focus of this research as it has been the subject of considerable debate over the cause of systematic variations in paleomagnetic direction across the ˜25 km wide pluton. Hollister et al. (2004) proposed that magnetization carried by lamellar magnetism in ilmenite-hematite was variably reset during reheating by emplacement of the younger Quottoon plutonic complex on the eastern margin of the Ecstall pluton, thus causing the systematic variations in paleomagnetic direction. To test this hypothesis we conducted a number of studies on samples from the Ecstall pluton. First, a detailed mineralogic study using scanning electron microscopy, and transmission electron microscopy found evidence of microstructural and mineralogic changes to the magnetic oxides of the Ecstall pluton as a function of distance from the Quottoon plutonic complex. Second, rock magnetic experiments on single crystals of Fe-Ti oxides confirm changes to the magnetic properties of single crystals that are related to both microstructure and distance from the Quottoon plutonic complex. Third, spatial trends in 40Ar/39Ar cooling ages from hornblende and biotite were found to be consistent with reheating by the Quottoon plutonic complex. In addition to reheating by the Quottoon plutonic complex, thermal modeling suggests that spatial trends in 40Ar/39Ar cooling ages are most consistent with a thermal history that also includes northeast side up tilt of the Ecstall. The Smith Island and Butedale plutons do not show evidence for tilting in their 40Ar/39Ar cooling age trends, and paleomagnetic directions from these plutons are approximately concordant with the

  8. Source variation for Mesozoic granitoid plutons in the White-Inyo Range, California, and implications for changes in the lithospheric structure

    Science.gov (United States)

    Gammel, E.; Nabelek, P. I.; Phillips, E. H. W.; Scott, S. R.; Sims, K. W. W.

    2015-12-01

    The White-Inyo Range (WIR) of eastern California lies to the east of Owen's Valley and the Sierra Nevada batholith (SNB). Over twenty recognized Mesozoic, granitic to gabbroic plutons intruded into Precambrian and Cambrian sedimentary units that were previously metamorphosed to the greenschist facies. These plutons represent intrusive equivalents of volcanics erupted during two magmatic events at ca. 180-167 Ma and 102-86 Ma (Coleman et al, 2003). The motivation of this study is to understand changes in magma sources over this time period. We propose there is a time-transgressive change in source material in the WIR. Preliminary trace element data suggest that Jurassic plutons were sourced from deep crustal material, whereas later Cretaceous plutons may have had a shallower origin. This is supported by high Sr/Y ratios in the Jurassic plutons (up to 300) and relatively lower ratios in Cretaceous plutons (down to 14). Chiaradia (2015) suggests elevated Sr/Y ratios are directly linked to increasing crustal thickness, therefore the WIR plutons may record the period of crustal thinning in this region or maturation of the crust that allowed shallower melting in the Cretaceous. The highest values also suggest possible adakitic source material. REE patterns suggest that the youngest plutons (e.g. Sage Hen Flat) are more similar to samples collected from the eastern Sierra Nevada batholith than older plutons with higher La/Yb ratios. Relatively flat patterns REE patterns of Tertiary basalts and a late diabase dike in the WIR are also similar to SNB samples. Another goal of this study is to determine the degree of mixing as a function of time during the emplacement of plutons in the range. Field and petrographic analyses suggest that older plutons represent more mafic materials and younger plutons are more granitic with mafic enclaves. We propose either (1) older plutons represent initial lower lithosphere melting, and with time, there is an increase of incorporation of

  9. Reworked old crust-derived shoshonitic magma: The Guarany pluton, Northeastern Brazil

    Science.gov (United States)

    Ferreira, Valderez P.; Sial, Alcides N.; Pimentel, Marcio M.; Armstrong, Richard; Guimarães, Ignez P.; da Silva Filho, Adejardo F.; de Lima, Mariucha Maria C.; da Silva, Thyego R.

    2015-09-01

    The 572 Ma Guarany stock consists of magmatic epidote-bearing hornblende monzodiorite to biotite granite that intruded Paleoproterozoic orthogneisses about 10 km inland from the coast in northeastern Brazil. Co-magmatic diorite enclaves and dikes are abundant throughout the pluton. The monzodiorite-granite pluton and diorite enclaves are shoshonitic and display continuous trends in variation diagrams. They display chemical and isotopic characteristics of crustal melts, such as enrichment in incompatible elements, high back-calculated initial 87Sr/86Sr ratios (avg. 0.71253), negative εNd (0.57Ga) values (avg. - 14.58), as well as high and variable (+ 9.1 to + 11.1‰VSMOW) δ18O (zircon) values. Correlations between O-isotope and whole-rock silica contents, as well as initial 87Sr/86Sr ratios with 1/Sr concentrations, suggest hybridization of a lower continental crustal melt with more felsic crustal rocks, concomitant with fractional crystallization. Amphibole chemistry and whole rock Zr, TiO2 and P2O5 contents suggest magma solidification at a pressure 7 kbar and near liquidus temperature 900 °C. The parental magma was likely formed by partial melting of old (tDM = 2.0 Ga) amphibolitic lower continental crustal rocks, in a post-collisional setting, probably triggered by underplating of mantle-derived mafic magma during the period of relaxation after collision.

  10. Geochemistry of uranium and thorium and natural radioactivity levels of the western Anatolian plutons, Turkey

    Science.gov (United States)

    Papadopoulos, Argyrios; Altunkaynak, Şafak; Koroneos, Antonios; Ünal, Alp; Kamaci, Ömer

    2017-01-01

    Seventy samples from major plutons (mainly granitic) of Western Anatolia (Turkey) have been analyzed by γ-ray spectrometry to determine the specific activities of 238U, 226Ra, 232Th and 40K (Bq/kg). Τhe natural radioactivity ranged up to 264 Bq/kg for 238U, 229.62 Bq/kg for 226Ra, up to 207.32 Bq/kg for 232Th and up to 2541.95 Bq/kg for 40K. Any possible relationship between the specific activities of 226Ra, 238U, 232Th and 40K and some characteristics of the studied samples (age, rock-type, colour, grain size, occurrence, chemical and mineralogical composition) was investigated. Age, major and trace element geochemistry, color, pluton location and mineralogical composition are likely to affect the concentrations of the measured radionuclides. The range of the Th/U ratio was large (0.003-11.374). The latter, along with 226Ra/238U radioactive secular disequilibrium, is also discussed and explained by magmatic processes during differentiation.

  11. Zircon SHRIMP Dating for the Weiya Pluton, Eastern Tianshan: Its Geological Implications

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zunzhong; GU Lianxing; WU Changzhi; LI Weiqiang; XI Aihua; WANG Shuo

    2005-01-01

    The timing of the emplacement of the Weiya pluton remains controversial due to the absence of systematic and precise dating.This paper reports zircon SHRIMP U-Pb dating of different lithologic phases in the Weiya pluton,and discusses the genesis and tectonic environment.The ages of gabbro,quartz syenite,diorite porphyrite and fine-grained granite are 236±6 Ma,246±6 Ma,233±8 Ma and 237±8 Ma,respectively.All these phases were formed in early-middle Indosinian (Triassic) in a post-orogenic environment.In addition to underplating,intraplating of mantle-derived magmas is also a substantial mechanism for magma generation and vertical accretion of the continental crust.Granitoid rocks are important products of vertical continental accretion as underplating evolves gradually to intraplating.The existence of post-orogenic Indosinian granites shows that the middle Tianshan orogenic belt underwent an important tectonic conversion from the Paleo-Asian ocean subduction-collision system to the Paleo-Tethys ocean regime.

  12. Oxygen isotope exchange kinetics between coexistent minerals and water in the Ertaibei granite pluton, northern Xinjiang

    Institute of Scientific and Technical Information of China (English)

    刘伟; 李志安; 赵志忠

    1996-01-01

    Coexistent minerals quartz, feldspar and biotite vary widely in δ18O value and display remarkable 18O/16O disequilibrium relations in the Ertaibei granite pluton, northern Xinjiang. The 18O/16O exchange reaction definitely occurred between granite and water. Initial δ18O values of the granite and exotic water are evaluated by the mass balance consideration. The results show that the 18O/16O exchange reaction is not necessarily accompanied by what geologists describe as petrological and mineralogiesl alteration effects, indicating that the exchange reaction occurs at a comparatively high temperature during subsolidus cooling of magmas. Exchange mechanism is mainly controlled by diffusion. It is demonstrated through quantitative modelling that the hydrothermal system associated with the Ertaibei pluton lived for 0.8-3 Ma, with a fluid flow rate of 3 × 10-14 mol · s-1 and water/rock (W/R) ratio of 0.79 - 3.08. Flow path and initial heterogeneity of the exotic metamorphic fluid are modelled with the δ1

  13. Tectonic significance of dykes in the Sarnu-Dandali alkaline complex, Rajasthan, northwestern Deccan Traps

    Institute of Scientific and Technical Information of China (English)

    Anjali Vijayan; Hetu Sheth; Kamal Kant Sharma

    2016-01-01

    Whether swarms of preferentially oriented dykes are controlled by regional stress fields, or passively exploit basement structural fabric, is a much debated question, with support for either scenario in individual case studies. The Sarnu-Dandali alkaline complex, near the northwestern limit of the Deccan Traps continental flood basalt province, contains mafic to felsic alkaline volcano-plutonic rocks and carbonatites. The complex is situated near the northern end of the 600 km long, NNWeSSE-trending Barmer-Cambay rift. Mafic enclave swarms in the syenites suggest synplutonic mafic dykes injected into a largely liquid felsic magma chamber. Later coherent dykes in the complex, of all compositions and sizes, dominantly strike NNWeSSE, parallel to the Barmer-Cambay rift. The rift formed during two distinct episodes of extension, NWeSE in the early Cretaceous and NEeSW in the late Cretaceous. Control of the southern Indian Dharwar structural fabric on the rift trend, as speculated previously, is untenable, whereas the regional Precambrian basement trends (Aravalli and Malani) run NEeSW and NNEeSSW. We therefore suggest that the small-scale Sarnu-Dandali dykes and the much larger-scale Barmer-Cambay rift were not controlled by basement structure, but related to contemporaneous, late Cretaceous regional ENEeWSW extension, for which there is varied independent evidence.

  14. Syn-extensional plutonism and peak metamorphism in the albion-raft river-grouse creek metamorphic core complex

    Science.gov (United States)

    Strickland, A.; Miller, E.L.; Wooden, J.L.; Kozdon, R.; Valley, J.W.

    2011-01-01

    The Cassia plutonic complex (CPC) is a group of variably deformed, Oligocene granitic plutons exposed in the lower plate of the Albion-Raft River- Grouse Creek (ARG) metamorphic core complex of Idaho and Utah. The plutons range from granodiorite to garnet-bearing, leucogranite, and during intrusion, sillimanite- grade peak metamorphism and ductile attenuation occurred in the country rocks and normal-sense, amphibolite-grade deformation took place along the Middle Mountain shear zone. U-Pb zircon geochronology from three variably deformed plutons exposed in the lower plate of the ARG metamorphic core complex revealed that each zircon is comprised of inherited cores (dominantly late Archean) and Oligocene igneous overgrowths. Within each pluton, a spread of concordant ages from the Oligocene zircon overgrowths is interpreted as zircon recycling within a long-lived magmatic system. The plutons of the CPC have very low negative whole rock ??Nd values of -26 to -35, and initial Sr values of 0.714 to 0.718, consistent with an ancient, crustal source. Oxygen isotope ratios of the Oligocene zircon overgrowths from the CPC have an average ??18O value of 5.40 ?? 0.63 permil (2SD, n = 65) with a slight trend towards higher ??18O values through time. The ??18O values of the inherited cores of the zircons are more variable at 5.93 ?? 1.51 permil (2SD, n = 29). Therefore, we interpret the plutons of the CPC as derived, at least in part, from melting Archean crust based on the isotope geochemistry. In situ partial melting of the exposed Archean basement that was intruded by the Oligocene plutons of the CPC is excluded as the source for the CPC based on field relationships, age and geochemistry. Correlations between Ti and Hf concentrations in zircons from the CPC suggest that the magmatic system may have become hotter (higher Ti concentration in zircon) and less evolved (lower Hf in zircon concentration) through time. Therefore, the CPC represents prolonged or episodic magmatism

  15. Petrogenesis and tectonic implications of the high-K Alamas calc-alkaline granitoids at the northwestern margin of the Tibetan Plateau: Geochemical and Sr-Nd-Hf-O isotope constraints

    Science.gov (United States)

    Zhang, Qichao; Liu, Yan; Huang, He; Wu, Zhenhan; Zhou, Qing

    2016-09-01

    The Alamas granitoid pluton in the eastern part of the Western Kunlun Orogen, the northwestern margin of the Tibetan Plateau, is composed of quartz diorite. Zircon separates from the pluton has SIMS U-Pb age of ∼446 Ma. Rocks from the pluton have a narrow range of SiO2 (56.84-62.57 wt%), MgO (1.76-2.94 wt%), and total alkalis (Na2O + K2O = 5.14-9.59 wt%), and are metaluminous and high-K calc-alkaline to shoshonitic in composition. They are enriched in light rare earth elements (LREEs), with (La/Yb)N = 14-25, and show weakly negative Eu anomalies. These rocks are relatively enriched in Sr (472-676 ppm) and Ba (435-2388 ppm), and depleted in Nb, Ta, Th, and Ti. Their εNd(t) values range from -6.4 to -8.4, and (87Sr/86Sr)i = 0.7184-0.7200. Zircons from the pluton show εHf(t) values of -1.4 to -8.8, and δ18O = 6.4-9.0‰. Geochemical data indicate that the granitoids were likely derived from the reworking of an ancient, deep crustal source, influenced by a minor mantle-derived component. Magmatic differentiation was dominated by the fractional crystallization of hornblende, biotite, and accessory minerals such as apatite, allanite, and Fe-Ti oxides. In summary, the Late Ordovician Alamas pluton is an I-type granitoid that was emplaced in a post-collisional environment, suggesting that this tectonic stage had already initiated prior to ∼445 Ma.

  16. Death Valley turtlebacks: Mesozoic contractional structures overprinted by Cenozoic extension and metamorphism beneath syn-extensional plutons

    Science.gov (United States)

    Pavlis, T. L.; Miller, M.; Serpa, L.

    2008-07-01

    The term turtleback was first coined to describe the curvilinear fault surfaces that produced a distinctive geomorphic form in the Black Mountains east of Death Valley, and although it was decades before their full significance was appreciated, they remain one of the most distinctive features of the extensional structure of the Death Valley region. Historically the interpretation of the features has varied markedly, and misconceptions about their character continue to abound, including descriptions in popular field guides for the area. It the 1990's, however, the full history of the systems began to be apparent from several key data: 1) the dating of the plutonic assemblage associated with the turtlebacks demonstrated that late Miocene, syn-extensional plutonism was fundamental to their formation; 2) the plutonic assemblage forms an intrusive sheet structurally above the turtlebacks, indicating a tie between much of the high grade metamorphism and Cenozoic plutonism; 3) a modern analog for the syn-extensional plutonism in the Black Mountains was recognized beneath Death Valley with the imaging of a mid-crustal magma body; 4) the Neogene structural history was worked out in the turtlebacks showing that folding of early-formed shear zones formed the turtleback anticlinoria but overprinting by brittle faults produced the final form as they cut obliquely across the older structure; and 5) the pre-extensional structural history was clarified, demonstrating that Mesozoic basement-involved thrust systems are present within the turtlebacks, but have been overprinted by the extensional system. An unresolved issue is the significance of Eocene U-Pb dates for pegmatites within the region, but presumably these relate somehow to the pre-extensional history. Miller and Pavlis (2005; E. Sci. Rev.) reviewed many features of the turtlebacks, and our working model for the region is that the turtlebacks originated as mid-crustal ductile-thrust systems within the Cordilleran fold

  17. Devonian alkaline magmatism in the northern North China Craton: Geochemistry, SHRIMP zircon U-Pb geochronology and Sr-Nd-Hf isotopes

    Directory of Open Access Journals (Sweden)

    Dingling Huang

    2017-01-01

    Full Text Available The Wulanhada pluton is among the rare suite of Devonian alkaline plutons occurring along the northern margin of the North China Craton (NCC. The intrusion is mainly composed of quartz-monzonite. Here we report zircon SHRIMP U-Pb data from this intrusion which shows emplacement age of ca. 381.5 Ma. The rock is metaluminous with high (Na2O + K2O values ranging from 8.46 to 9.66 wt.%. The REE patterns of the rocks do not show any Eu anomaly whereas the primitive-mantle-normalized spider diagram shows strong positive Sr and Ba anomalies. The Wulanhada rocks exhibit high initial values of (87Sr/86Srt = 0.70762–0.70809, low ɛNd(t = −12.76 to −12.15 values and negative values of ɛHf(t = −23.49 to −17.02 with small variations in (176Hf/177Hft (0.281873–0.282049. These geochemical features and quantitative isotopic modeling results suggest that the rocks might have been formed through the partial melting of Neoarchean basic rocks in the lower crust of the NCC. The Wulanhada rocks, together with the Devonian alkaline rocks and mafic-ultramafic complex from neighboring regions, constitute a post-collisional magmatic belt along the northern NCC.

  18. Alkaline Water and Longevity: A Murine Study.

    Science.gov (United States)

    Magro, Massimiliano; Corain, Livio; Ferro, Silvia; Baratella, Davide; Bonaiuto, Emanuela; Terzo, Milo; Corraducci, Vittorino; Salmaso, Luigi; Vianello, Fabio

    2016-01-01

    The biological effect of alkaline water consumption is object of controversy. The present paper presents a 3-year survival study on a population of 150 mice, and the data were analyzed with accelerated failure time (AFT) model. Starting from the second year of life, nonparametric survival plots suggest that mice watered with alkaline water showed a better survival than control mice. Interestingly, statistical analysis revealed that alkaline water provides higher longevity in terms of "deceleration aging factor" as it increases the survival functions when compared with control group; namely, animals belonging to the population treated with alkaline water resulted in a longer lifespan. Histological examination of mice kidneys, intestine, heart, liver, and brain revealed that no significant differences emerged among the three groups indicating that no specific pathology resulted correlated with the consumption of alkaline water. These results provide an informative and quantitative summary of survival data as a function of watering with alkaline water of long-lived mouse models.

  19. Compositional and kinetic controls on liquid immiscibility in ferrobasalt-rhyolite volcanic and plutonic series

    Science.gov (United States)

    Charlier, Bernard; Namur, Olivier; Grove, Timothy L.

    2013-07-01

    We present major element compositions of basalts and their differentiation products for some major tholeiitic series. The dry, low-pressure liquid lines of descent are shown to approach or intersect the experimentally-defined compositional space of silicate liquid immiscibility. Ferrobasalt-rhyolite unmixing along tholeiitic trends in both volcanic and plutonic environments is supported by worldwide occurrence of immiscible globules in the mesostasis of erupted basalts, unmixed melt inclusions in cumulus phases of major layered intrusions such as Skaergaard and Sept Iles, and oxide-rich ferrogabbros closely associated with plagiogranites in the lower oceanic crust. Liquid immiscibility is promoted by low-pressure, anhydrous fractional crystallization that drives the low Al2O3, high FeO liquids into the two-liquid field. Kinetic controls can be important in the development of two-liquid separation. The undercooling that occurs at the slow cooling rates of plutonic environments promotes early development of liquid immiscibility at higher temperature. In contrast rapid cooling in erupted lavas leads to large undercoolings and liquid immiscibility develops at significantly lower temperatures. Unmixing leads to the development of a compositional gap characterized by the absence of intermediate compositions, a feature of many tholeiitic provinces. The compositions of experimental unmixed silica-rich melts coincide with those of natural rhyolites and plagiogranites with high FeOtot and low Al2O3, suggesting the potential role of large-scale separation of immiscible Si-rich liquid in the petrogenesis of late-stage residual melts. No trace of the paired ferrobasaltic melt is found in volcanic environments because of its uneruptable characteristics. Instead, Fe-Ti ± P-rich gabbros are the cumulate products of immiscible Fe-rich melts in plutonic settings. The immiscibility process may be difficult to identify because both melts crystallize the same phases with the same

  20. Oxygen Isotope Perspectives on Magma Sources and Pluton Assembly in Convergent Margin Batholiths

    Science.gov (United States)

    Lackey, J.

    2008-12-01

    Oxygen isotope (δ18O) analysis of zircon in the Sierra Nevada batholith (SNB) yields fresh insight on the origin of this and other convergent margin batholiths. Zircon precisely and accurately maps (δ18O) variation by circumventing the effects of differentiation and sub-solidus alteration[1]. New temporal and spatial δ18O patterns are recognized, and the findings have bearing in current debates on the tempo and mode of pluton and intrusive suite assembly [2-4]. At large scales, regional belts of high and low δ18O reveal markedly contrasting budgets of crust and mantle in magma sources at different points during formation of the batholith. Contrary to original thinking, recycling of supracrustal rocks is greater in the western than eastern SNB. Gradients of δ18O show variable input of crust and mantle within these regional belts; however, sharp shifts in δ18O between some belts suggest pre-batholith lithospheric breaks. Generally, δ18O breaks do not coincide with the 0.706 Sri line suggesting isotopic decoupling, either in sources or during crustal contamination. Where present, crustal contamination is limited to veneers on plutons, and is largely restricted to the western SNB. Careful investigation of individual intrusive suites, reveals details of source longevity. In the Tuolumne suite, limited variability of δ18O suggests remarkably source homogeneity despite evidence for protracted emplacement[2,4]. In contrast, the John Muir suite shows distinct trends in its older and younger plutons, with a δ18O transition recorded in the Lake Edison granodiorite. Thus, some suites may draw from stable sources over several million years, with differentiation in the upper crust creating zoning and textural diversity; others record source switching or depletion of sources. Over time, shifts in δ18O in the SNB are punctuated by major pulses of magmatism suggesting reorganization of sources, likely in response to intra-arc deformation[5]. Overall, results show that a

  1. Svařování rámu jízdního kola z titanové slitiny

    OpenAIRE

    Richter, Tomáš

    2010-01-01

    Tato bakalářská práce se zabývá svařováním rámu jízdního kola z titanové slitiny. První část je zaměřena na samotné jízdní kolo. Jsou zde rozebrány typy kol, materiály, ze kterých se rámy vyrábí a vliv některých rozměrů na jízdní vlastnosti. Další kapitola je věnována titanu. Tato kapitola popisuje vlastnosti titanu a jeho slitin používaných na rámy. Dále je popsána metoda TIG, kterou se titan nejčastěji svařuje. Tato metoda je zde zmíněna obecně i konkrétně pro svařování titanu. Poslední čás...

  2. Growing season changes in Fennoscandia and Kola peninsula during the period 1982 to 1999 - Implications for reindeer husbandry (In Norwegian with Summary in English

    Directory of Open Access Journals (Sweden)

    Hans Tømmervik

    2005-04-01

    Full Text Available Climate change and particularly variations in air temperature have significant impacts on the growth rhythm of plants where these occur at the limits of their natural distribution range, especially at northern latitudes. Our study area, Fennoscandia and Kola Peninsula, is characterized by large regional climatic differences from south to north, from west to east, and from lowland to mountains. Accordingly, the region is well suited for looking for evidence of climatic change and studying regional differences in the response of such change. The International Panel on Climate Change (IPCC reports that the projected warming in northern Europe is greater than for many other regions of the world. Therefore major physical and ecological changes are expected. On land, there will be a tendency for shifts in major biomes such as tundra and boreal forest. Permafrost will decline, trees and shrubs will encroach northern tundra, and broad-leaved trees may encroach coniferous forests. Net primary productivity in ecosystems is likely to increase. The temperature level at the end of the 20th century is ca. 0.5 oC higher than in the 1930 for the Northern hemisphere (IPCC and World Meteorological Organization. Other studies show that in the period 1890-1999, the increase in temperature over Fennoscandia varies between 0.02 (Karasjok and 0.1 oC decade-1 (Helsinki, and they also showed that at several stations within the area the spring temperatures have increased steadily throughout the 20th century. Most stations experienced low spring temperatures in the beginning of the century, and rather high temperatures around 1950. At present, the winter temperature levels are considerably higher than in the rest of the period. However, at northern stations the winter temperatures were higher in the 1930s than at present. Phenological registrations have been used word-wide to look for possible effects of climate change, but within Fennoscandia the problem is that

  3. Intermetallic compounds, copper and palladium alloys in Au-Pd ore of the Skaergaard pluton, Greenland

    Science.gov (United States)

    Rudashevsky, N. S.; Rudashevsky, V. N.; Nielsen, T. F. D.

    2015-12-01

    Copper-palladium intermetallic compounds and alloys (2314 grains) from the Au-Pd ore of the Skaergaard layered gabbroic pluton have been studied. Skaergaardite PdCu, nielsenite PdCu3, (Cu,Pd)β, (Cu,Pd)α, (Pd,Cu,Au,Pt) alloys, and native palladium have been identified as a result of 1680 microprobe analyses. The average compositions and various chemical varieties of these minerals are characterized, as well as vertical and lateral zoning in distribution of noble metals. The primary Pd-Cu alloys were formed within a wide temperature interval broadly synchronously with cooling and crystallization of host gabbro and in close association with separation of Fe-Cu sulfide liquid. In the course of crystallization of residual gabbroic melt enriched in iron, noble and heavy metals and saturated with the supercritical aqueous fluid, PGE and Au are selectively concentrated in the Fe-Cu sulfide phase as Pd-Cu and Cu-Au alloys.

  4. Neo-tectonic fracturing after emplacement of quaternary granitic pluton in the Kakkonda geothermal field, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Doi, N.; Kato, O. [JMC Goethermal Eng. Co., Ltd., Iwate-ken (Japan); Kanisawa, S.; Ishikawa, K. [Tohoku Univ., Sendai (Japan)

    1995-12-31

    The fracture which occurs in the Kakkonda geothermal system was formed by neo-tectonic stress after the emplacement of the neo-granite (Quaternary Kakkonda Granite) at middle Pleistocene to recent. The characteristic contrast in permeability at ca.1.5 km is strongly controlled by the contact metamorphic zone, especially cordierite and higher grade metamorphic zones, in which the high temperature (320{degrees}C<) and low permeable deep reservoir was created. The five geothermal wells 2.5-3.0 km deep have clarified that a microearthquake zone below -1.0 km shows high permeability especially at the margin of the Kakkonda Granite, and low permeability outside of a microearthquake zone. The Kakkonda Granite is a composite pluton which has very few fractures inside of it. Thus, neo-tectonic fracturing has developed in the non-metamorphosed Tertiary formations and the margin of the Kakkonda Granite.

  5. Exploring the plutonic crust at a fast-spreading ridge:new drilling at Hess Deep

    Energy Technology Data Exchange (ETDEWEB)

    Gillis, Kathryn M. [Univ. of Victoria, BC (Canada). School of Earth and Ocean Sciences; Snow, Jonathan E. [Univ. of Houston, Houston, TX (United States). Earth & Atmospheric Sciences; Klaus, Adam [Texas A & M Univ., College Station, TX (United States). Integrated Ocean Drilling Program (IODP). United States Implementing Organization.; Guerin, Gilles [Lamont-Doherty Earth Observatory of Columbia Univ., Palisades, NY (United States). Borehole Research Group; Abe, Natsue [Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka (Japan). Inst. for Research on Earth Evolution (IFREE); Akizawa, Norikatsu [Kanazawa Univ. (Japan). Dept. of Earth Sciences; Ceuleneer, Georges [Univ. Paul Sabatier, Toulouse (France). Observatoire Midi-Pyrenees (UMS 831), CNRS; Cheadle, Michael J. [Univ. of Wyoming, Laramie, WY (United States). Dept. of Geology and Geophysics; Adriao, Alden de Brito [Federal Univ. of Rio Grande do Sul, Porto Alegre (Brazil). Geology Inst. (IGEO); Faak, Kathrin [Ruhr Univ., Bochum (Germany). Geological Inst.; Falloon, Trevor J. [Univ. of Tasmania, Hobart, TAS (Australia). Inst. for Marine and Antarctic Studies; Friedman, Sarah A. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology; Godard, Marguerite M. [Univ. Montpellier II (France). Geosciences Montpellier-UMR 5243; Harigane, Yumiko [National Inst. of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan). Marine Geology Dept.; Horst, Andrew J. [Syracuse Univ., NY (United States). Dept. of Earth Science; Hoshide, Takashi [Tohoku Univ., Sendai (Japan). Graduate School of Science; Ildefonse, Benoit [Univ. Montpellier II (France). Lab. de Tectonophysique; Jean, Marlon M. [Northern Illinois Univ., DeKalb, IL (United States). Dept. of Geology and Environmental Geosciences; John, Barbara E. [Univ. of Wyoming, Laramie, WY (United States). Dept. of Geology and Geophysics; Koepke, Juergen H. [Univ. of Hannover (Germany). Inst. of Mineralogy; Machi, Sumiaki [Kanazawa Univ. (Japan). Dept. of Earth Sciences; Maeda, Jinichiro [Hokkaido Univ., Sapporo (Japan). Dept. of Natural History Sciences; Marks, Naomi E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Chemistry and Material Sciences Dept.; McCaig, Andrew M. [Univ. of Leeds (United Kingdom). School of Earth and Environment; Meyer, Romain [Univ. of Bergen (Norway). Dept. of Earth Science and Centre for Geobiology; Morris, Antony [Univ. of Plymouth (United Kingdom). School of Earth, Ocean & Environmental Sciences; Nozaka, Toshio [Okayama Univ. (Japan). Dept. of Earth Sciences; Python, Marie [Hokkaido Univ., Sapporo (Japan). Dept. of Earth and Planetary Sciences; Saha, Abhishek [Indian Inst. of Science (IISC), Bangalore (India). Centre for Earth Sciences; Wintsch, Robert P. [Indiana Univ., Bloomington, IN (United States). Dept. of Geological Sciences

    2013-02-28

    Integrated Ocean Drilling Program (IODP) Hess Deep Expedition 345 was designed to sample lower crustal primitive gabbroic rocks that formed at the fast-spreading East Pacific Rise (EPR) in order to test models of magmatic accretion and the intensity of hydrothermal cooling at depth. The Hess Deep Rift was selected to exploit tectonic exposures of young EPR plutonic crust, building upon results from ODP Leg 147 as well as more recent submersible, remotely operated vehicle, and near-bottom surveys. The primary goal was to acquire the observations required to test end-member crustal accretion models that were in large part based on relationships from ophiolites, in combination with mid-ocean ridge geophysical studies. This goal was achieved with the recovery of primitive layered olivine gabbros and troctolites with many unexpected mineralogical and textural relationships, such as the abundance of orthopyroxene and the preservation of delicate skeletal olivine textures.

  6. The plutonic-volcanic connection: are we even on the right track? (Invited)

    Science.gov (United States)

    Lundstrom, C.; Chakraborty, P.; Zambardi, T.

    2013-12-01

    The connection between silicic volcanic and plutonic rocks is full of contradictions. Foremost, granitic plutons reflect long slow incremental emplacement yet vast amounts of aphyric ignimbrite can be erupted rapidly. Heat flow, geophysical tomography, geochronology, geochemistry and petrology all provide observations, yet we are far from any consensus. The two most popular suggestions for forming ignimbrites, extraction of partial melt from a granitic upper crust reservoir or lower crustal hot zone melting, are each inconsistent with some observations/constraints. 100% melting of a granite mush, which may be consistent with many observations, was previously proposed1 but dismissed due to the large amount of latent heat needed to completely melt a mush. This work first presents new non-traditional isotope ratio data (Fe, Si) for plutonic and volcanic rocks suites showing that like Harker diagrams, volcanics and plutonics produce identical systematic behavior with differentiation. δ56Fe forms upwardly curving trends with increasing silica whereas δ30Si increases linearly. The logical deduction is that volcanics reflect 100% mobilization of a granite mush (not necessarily melting). While the origin of NTSI variations remains debated, the systematic NTSI trends are consistent with prediction of a top-down thermal migration zone refining (TMZR) process2. In part 2, we assume TMZR generates a granitic mush and propose that an instability in this mush leads to a runaway effect that results in eruption of aphyric ignimbrite. Experiments show that wet andesite evolves to granite at the cold (400°C) end of a thermal gradient3 with hydrous peralkaline melt existing interstitially. Previous work4 shows that such melts show retrograde immiscibility, segregating into a water rich melt and a water poor melt with temperature increase. Thus, as the mush builds down into hot crust, it crosses the immiscibility boundary triggering release of the water-rich phase; buoyant rise and

  7. Post-collisional adakitic biotite plagiogranites from Guangtoushan pluton (Mianxian, central China): Petrogenesis and tectonic implication

    Institute of Scientific and Technical Information of China (English)

    QIN Jiangfeng; LAI Shaocong; LI Yongfei

    2007-01-01

    The post-collisional Guangtoushan pluton intruded into the Mianlue suture, Central China. Geochemi-cally, the Guangtoushan biotite plagiogranites show many close compositional similarities to high-silica adakites from the supra-subduction zone setting, but tend to have a higher concentration of K2O (3.22%-3.84%). Chondrite-normalized rare earth element pattems are characterized by high ratios of (La/Yb)N, concave-upward shapes of the heavy rare earth element (HREE), and a lack of significant Eu anomalies. In conjunction with high abundances of Ba and Sr, as well as low abundances of Y and HREE, these pattems suggest a feldspar-poor, garnet±amohibole-rich fractionation mineral assemblage. Coupled with previous studies, we suggest that the Guangtoushan biotite plagiogranites were likely to be caused by subducting slab break-off during the late orogenic stage in the West Qinling orogenic belt.

  8. The probable continuum between emplacement of plutons and mare volcanism in lunar crustal evolution

    Science.gov (United States)

    Pieters, Carle M.

    1991-01-01

    A scenario for the formation of the Moon is advanced and is argued to be consistent with both known data and the leading hypothesis regarding the formation of the Moon. It is concluded that, although the volume of mare basalts is estimated to be only 0.1 percent of the lunar total, this value should not be taken to represent the amount of partial melt produced within the lunar interior, nor should the mare basalts be viewed as representing the only products of internal heating. The actual amount of magnetic activity is certain to be substantially larger, but cannot be estimated without a global assessment of lunar highland heterogeneity and the character, scale, and abundance of lunar plutons.

  9. Pluton emplacement and magmatic arc construction: A model from the Patagonian batholith

    Science.gov (United States)

    Bruce, Robert; Nelson, Eric; Weaver, Stephen

    1988-01-01

    A model of batholithic construction in Andean arcs and its applicability to possibly similar environments in the past is described. Age and compositional data from the Patagonian batholith of southern Chile show a long history of magmatism in any given area (total age range is 15 to 157 Ma), but different regions appear to have different magmatic starting ages. Furthermore, mafic rocks seem to be the oldest components of any given region. An assembly line model involving semicontinuous magmatism and uplift was outlined, which has implications for other terranes: uplift rates will be proportional to observed ranges in age, and total uplift will be proportional to the age of the oldest pluton in any given area. It is suggested that misleading results would be obtained if only small areas of similar terranes in the Archean were available for study.

  10. A Structural-Thermal Model of the Karkonosze Pluton (Sudetes Mountains, SW Poland) for Hot Dry Rock (HDR) Geothermal Use

    Science.gov (United States)

    Bujakowski, Wiesław; Barbacki, Antoni; Miecznik, Maciej; Pająk, Leszek; Skrzypczak, Robert

    2016-12-01

    The main objective of this study was to develop a spatial temperature distribution of the Karkonosze Pluton to indicate optimum locations for HDR systems at drillable depth. HDR geothermal technology makes it possible to extract heat from the Earth in areas where no hydro-geothermal resources are present. To produce electricity in a binary cycle, system temperatures of > 100°C are usually required. In this paper, the authors have analysed the potential opportunities for applying HDR technology in the area of the Karkonosze Pluton, which is regarded as an optimum location for the application of the HDR concept (due to the potential for stimulation offered by the mechanical properties of the granites, radiogenic heat production, modern tectonic activity, and the thickness of the pluton). The model used in the analysis, which takes into account a hypothetical assessment of the manner and paths of fluid migration within the pluton, provides an insight into the spatial distribution of subsurface temperatures. It thus allows the location of relatively shallow high-temperature zones, which are optimal for the efficient application of HDR technology, to be identified. With respect to this technology, the Szklarska Poręba area and the NE part of the pluton seem to be better targets than the Cieplice central area, where the model indicated much lower temperatures (e.g. at a depth of 5,000 m, estimated temperatures in the vicinity of Szklarska Poręba were about 185°C and in the vicinity of Cieplice they were about 140°C).

  11. Spatially controlled Fe and Si isotope variations: an alternative view on the formation of the Torres del Paine pluton

    Science.gov (United States)

    Gajos, Norbert A.; Lundstrom, Craig C.; Taylor, Alexander H.

    2016-11-01

    We present new Fe and Si isotope ratio data for the Torres del Paine igneous complex in southern Chile. The multi-composition pluton consists of an approximately 1 km vertical exposure of homogenous granite overlying a contemporaneous 250-m-thick mafic gabbro suite. This first-of-its-kind spatially dependent Fe and Si isotope investigation of a convergent margin-related pluton aims to understand the nature of granite and silicic igneous rock formation. Results collected by MC-ICP-MS show a trend of increasing δ56Fe and δ30Si with increasing silica content as well as a systematic increase in δ56Fe away from the mafic base of the pluton. The marginal Torres del Paine granites have heavier Fe isotope signatures (δ56Fe = +0.25 ± 0.02 2se) compared to granites found in the interior pluton (δ56Fe = +0.17 ± 0.02 2se). Cerro Toro country rock values are isotopically light in both Fe and Si isotopic systems (δ56Fe = +0.05 ± 0.02 ‰; δ30Si = -0.38 ± 0.07 ‰). The variations in the Fe and Si isotopic data cannot be accounted for by local assimilation of the wall rocks, in situ fractional crystallization, late-stage fluid exsolution or some combination of these processes. Instead, we conclude that thermal diffusion or source magma variation is the most likely process producing Fe isotope ratio variations in the Torres del Paine pluton.

  12. Magma intrusion and accumulation in the southern Altiplano: Structural observations from the PLUTONS project

    Science.gov (United States)

    West, M. E.; Christensen, D. H.; Pritchard, M. E.; Del Potro, R.; Gottsmann, J.; Unsworth, M.; Minaya, E.; Sunagua, M.; McNutt, S. R.; Yu, Q.; Farrell, A. K.

    2012-12-01

    The PLUTONS project is attempting to capture the process of magma intrusion and pluton formation, in situ, through multi-disciplinary study of known magmatic inflation centers. With support from the NSF Continental Dynamics program, and a sister project in the UK funded by NERC, two such centers are receiving focused study. Uturuncu volcano in the Altiplano of southern Bolivia is being investigated with combined seismics, magnetotellurics, geodesy, microgravity, geomorphology, petrology, geochemistry, historical studies and modeling. 350 km to the south, comparable investigations are targeting the Lastarria-Cordon del Azufre complex. Field studies are ongoing into 2013. In this presentation we highlight results from Uturuncu that bear on the crustal magmatic process. Seismic tomography, gravity and magnetotellurics indicate a complex structure in the upper 20 km with some evidence for partial melt. Seismic receiver functions indicate a layer of very low velocities across the region at 15-25 km depth that is almost certainly melt-rich. High conductivities corroborate the interpretation of a partial melt component to this layer. In addition to the throughgoing melt layer, seismic velocities and attenuation indicate shallow features above the melt body extending upward toward the surface. It is not clear whether these features are associated with recent uplift or are remnants from a previous period of activity. Uturuncu is seismically active with hundreds of locatable earthquakes each year. Seismic lineations and swarm behavior suggest that the seismicity reflects regional stress patterns. While there is little evidence that these earthquakes are the direct result of magmatic intrusion, the resulting high heat flow may be hastening existing strains.

  13. Metasomatic Stages and Scapolitization Effects on Chemical Composition of Pasveh Pluton, NW Iran

    Institute of Scientific and Technical Information of China (English)

    S A Mazhari; S Amini; J Ghalamghash; F Bea

    2011-01-01

    Pasveh gabbros are mafic component of a plutonic complex in the northwest SanandajSirjan Zone.These cumulative rocks are composed of plagioclase and calcic clinopyroxene (Cpx),which yield unusually high CaO (>19 wt.%) in whole-rock chemistry.Petrographical and geochemical data suggest that Pasveh gabbros can be divided into two groups:free scapolite and scapolite-bearing gabbros.The second group has higher Na2O,K2O,and P2O5 relative to free scapolite ones and is enriched in LIL (large ion lithophile) and HFS (high field strength) elements.Two stages of metasomatism affected the primary composition of mafic rocks.Firstly,high temperature reaction caused to invert primary high Ti clinopyroxene to low Ti clinopyroxene+high Ti amphibole.This reaction was extensive and included all gabbrolc samples.Hydrothermal fluids involved in this process can be derived from dehydration reactions of country rocks or from other magmas incorporated in the formation of Pasveh complex pluton.The second metasomatic stage relates to scapolitization of limited parts of gabbroic rocks.An external saline fluid,which is composed of major NaCI and minor KCI and P2O5 components,impacted locally on Pasveh gabbros and formed the second metasomatic stage.Possible sources of Na and CI are primary evaporites or brines,which were present in the host sediments of the gabbros.The carbonate-free nature of these hydrothermal fluids suggests that hydrothermal fluids responsible for the formation of scapolite in Pasveh gabbros are derived from marine evaporitic parentage.

  14. Structural evolution of the Rieserferner Pluton: insight into the localization of deformation and regional tectonics implications

    Science.gov (United States)

    Ceccato, Alberto; Pennacchioni, Giorgio

    2016-04-01

    The Rieserferner pluton (RFP, Eastern Alps, 32.2±0.4 Ma, Romer et al. 2003) represents a relatively deep intrusion (12-15 km; Cesare, 1994) among Periadriatic plutons. The central portion of the RFP consists of dominant tonalites and granodiorites that show a sequence of solid-state deformation structures developed during pluton cooling and exhumation. This sequence includes: (1) quartz veins, filling two set of steeply-dipping joints trending respectively E-W and NW-SE, commonly showing a millimetric grain size and associated with strike-slip displacement. (2) Quartz- and locally epidote-filled shallowly E-dipping joint set, commonly exploited as discrete derived from both the quartz veins and the host tonalite. These mylonites show a composite sense of shear with a first stage of left-lateral strike-slip followed by a top-to-E dip-slip (normal) movement. The synmylonitic assemblage includes biotite + plagioclase + white mica + epidote ± sphene ± garnet. (3) Set of N-S-trending steeply-dipping joints. These joints are concentrated in zones 1-2 m wide, separated by otherwise un-jointed domains a few tens to hundred meters wide, and are commonly exploited as brittle-ductile faults with dominant dip-slip (normal) kinematics. The mineral assemblage of fault rocks includes white mica + calcite ± chlorite ± quartz. The joints/faults are locally involved in folding. (4) Mafic dikes, dated at 26.3±3 Ma (Steenken et al., 2000), locally injecting the N-S trending set of joints. (5) Cataclasite- and pseudotachylyte-bearing faults also forming a set of steeply-dipping N-S-trending structures. These faults are commonly associated with epidote veins surrounded by bleaching haloes. (6) Zeolite-bearing faults marked by whitish cataclasites, fault gouges and mirror-like surfaces. These faults have a complex oblique- to strike-slip kinematics with an overall N-S trending lineation. As observed in other plutons (e.g. Adamello; Pennacchioni et al., 2006), the network of

  15. Handbook of Indigenous Foods Involving Alkaline Fermentation

    NARCIS (Netherlands)

    Sarkar, P.K.; Nout, M.J.R.

    2014-01-01

    This book details the basic approaches of alkaline fermentation, provides a brief history, and offers an overview of the subject. The book discusses the diversity of indigenous fermented foods involving an alkaline reaction, as well as the taxonomy, ecology, physiology, and genetics of predominant m

  16. Petrogenesis and tectonic setting of Mingnandong pluton in Yanbian area:Constraints from petro-geochemistry and zircon U-Pb ages%延边地区明南洞岩体的成因及构造背景:岩石地球化学、锆石U-Pb年龄的制约

    Institute of Scientific and Technical Information of China (English)

    雷聪聪; 李世超; 刘正宏; 徐仲元; 张超; 白新会

    2014-01-01

    In this paper Mingnandong pluton was studied throughly by such means as field observation, LA-ICP-MS zircon U-Pb isotopic measurement and petro-geochemistry. The results show that Mingnandong pluton was formed in the Early Jurassic (180.47± 0.71Ma). Chemical analyses yielded the following data for Mingnandong pluton: SiO2=60.71%-67.72%, Al2O3=15.60%-17.44%, Na2O+K2O=6.79%-7.63%, K2O/Na2O=0.61-1.01 and A/CNK=0.94-1.01, implying high-potassium calc-alkaline I-type granites. Besides, Mingnandong pluton is enriched in light rare earth elements and large ion lithophile elements, and depleted in heavy rare earth elements and high field strength elements. These features suggest that Mingnandong pluton has obvious characteristics of active continental margin and volcanic arc granites. The ingredient zonation parallel to the orientation of the subduction of oceanic crust made up of cale-alkaine, high-K calc-alkaline granites and the bimodal volcanic rock association from Yanbian and Taiping Mountain to Xiao Hinggan Mountains and Zhangguangcai Mountain indicate the orientation of the subduction of ancient Pacific plate. In a word, the emplacement of Mingnandong pluton was influenced by the subduction of ancient Pacific plate in the Early Jurassic.%通过野外观测、锆石LA-ICP-MS U-Pb同位素测定及岩石地球化学等手段,详细地对延边地区明南洞岩体进行了研究。研究表明,延边地区明南洞岩体的成岩年龄为(180.5±0.7) Ma,为早侏罗世岩浆事件的产物。明南洞岩体中SiO2含量为60.71%~67.72%,Al2O3含量为15.60%~17.44%,全碱(Na2O+K2O)值为6.79%~7.63%,K2O/Na2O值为0.61~1.01,A/CNK=0.94~1.01,属高钾钙碱性I型花岗岩,并具有富集轻稀土元素和大离子亲石元素,亏损重稀土元素和高场强元素的特征。以上特征表明,明南洞岩体具有显著的活动大陆边缘及火山弧花岗岩的特点。延边-太平岭地区的陆缘钙碱性、高钾钙碱性花岗岩到张

  17. Association of alkaline phosphatase phenotypes with arthritides

    Directory of Open Access Journals (Sweden)

    Padmini A

    2004-01-01

    Full Text Available Arthritides, a symmetrical polyarticular disease of the bone are a heterogenous group of disorders in which hereditary and environmental factors in combination with an altered immune response appear to play a causative and pathogenic role in its occurrence. Alkaline phosphatase (ALP is an enzyme found in all tissues, with particularly high concentrations of ALP observed in the liver, bile ducts, placenta, and bone.Alkaline phosphatase is an orthophosphoric monoester phosphohydrolase catalyzing the hydrolysis of organic esters at alkaline pH, indicating that alkaline phosphatase is involved in fundamental biological processes.1 The present study envisages on identifying the specific electromorphic association of alkaline phosphatase with arthritides. Phenotyping of serum samples was carried out by PAGE (Polyacrylamide gel electrophoresis following Davies (19642 protocol on 41 juvenile arthritis, 150 rheumatoid arthritis and 100 osteo arthritis apart from, 25 normal children and 100 adult healthy subjects. Phenotyping of alkaline phosphatase revealed an increase in preponderance of p+ and p++ phenotypes in juvenile, rheumatoid and osteo arthritic patients. However a significant association of these phenotypes was observed only with rheumatoid arthritis condition (c2:17.46. Similarly, a significant increase of p+ phenotypes in female rheumatoid arthritis patients was observed (c2:14.973, suggesting that the decrease in p° (tissue non specific synthesis/secretion of alkaline phosphatase could be associated with decreased mineralization and ossification process in arthritis condition.

  18. Alkaline solution neutralization capacity of soil.

    Science.gov (United States)

    Asakura, Hiroshi; Sakanakura, Hirofumi; Matsuto, Toshihiko

    2010-10-01

    Alkaline eluate from municipal solid waste (MSW) incineration residue deposited in landfill alkalizes waste and soil layers. From the viewpoint of accelerating stability and preventing heavy metal elution, pH of the landfill layer (waste and daily cover soil) should be controlled. On the other hand, pH of leachate from existing MSW landfill sites is usually approximately neutral. One of the reasons is that daily cover soil can neutralize alkaline solution containing Ca(2+) as cation. However, in landfill layer where various types of wastes and reactions should be taken into consideration, the ability to neutralize alkaline solutions other than Ca(OH)(2) by soil should be evaluated. In this study, the neutralization capacities of various types of soils were measured using Ca(OH)(2) and NaOH solutions. Each soil used in this study showed approximately the same capacity to neutralize both alkaline solutions of Ca(OH)(2) and NaOH. The cation exchange capacity was less than 30% of the maximum alkali neutralization capacity obtained by the titration test. The mechanism of neutralization by the pH-dependent charge can explain the same neutralization capacities of the soils. Although further investigation on the neutralization capacity of the soils for alkaline substances other than NaOH is required, daily cover soil could serve as a buffer zone for alkaline leachates containing Ca(OH)(2) or other alkaline substances.

  19. Application of IBA to determine the effects of Kolaviron (Garcinia kola) on the elemental metabolism in the rat liver and kidney

    Energy Technology Data Exchange (ETDEWEB)

    Mars, J.A.; Kunsevi-Kilola, C.; Gihwala, D. [Department of Biomedical Sciences, Cape Peninsula University of Technology, PO Box 1906, Bellville, 7535 (South Africa)

    2013-07-01

    Full text: Poor or no antioxidant activity has been implicated in the aetiology of various pathologies. Since antioxidants are mostly derived from natural resources, the search for medicinal plants, that can either cure or alleviate ailments, has been phenomenal over the past decades. One plant, Garcinia kola, the oil of which is termed kolaviron, has been identified to have possible antioxidant activity [1]. Trace elements such as Fe, Mn, Cu, Zn and Se, form an integral part in antioxidant activity, especially in organ metabolism. In this study organ (Iiver and kidney) metabolism of major such as C, O, N, S, and trace elements is investigated. The kolaviron was dissolved in corn oil. Two groups (control and experimental) of Wistar rats were selected. The animals were housed in accordance with the WHO animal regulations. Both groups had ad libitum access to standard rat chow and potable tap water. The control group was fed, by gavage, with 200 microlitre of the solution of kolaviron in com oil once per day for a period of 4 weeks. After this period the animals were sacrificed by intraperitoneal injection of pentobarbitone. The organs were excised and homogenised into smaller parts which were freeze-dried - 80 deg C. The freeze-dried organ was then pulverized and press into a palette. Concentrations of trace elements were determined with proton induced X-ray emission (PIXE). PIXE was selected since with this technique concentrations down to minimum detection limits (MDLs) of parts per million (ppm) can be determined. A beam of 3 MeV protons was used for bombardment and a Be filter of 125 micrometer thickness for absorption. Backscattering spectrometry (BS) was used to determine the matrix composition. PIXE and BS measurements were determined simultaneously. Scanning electron microscopy was used both as complementary and supplementary to PIXE and BS. Statistical tests of p < 0.5 were considered significant. 1] Ogada and Braide (2009) Nig. J. Physio. Sci., vol. 24

  20. Kolaviron, a biflavonoid complex of Garcinia kola seeds modulates apoptosis by suppressing oxidative stress and inflammation in diabetes-induced nephrotoxic rats.

    Science.gov (United States)

    Ayepola, Omolola R; Cerf, Marlon E; Brooks, Nicole L; Oguntibeju, Oluwafemi O

    2014-12-15

    Diabetic nephropathy is a complex disease that involves increased production of free radicals which is a strong stimulus for the release of pro-inflammatory factors. We evaluated the renal protective effect of kolaviron (KV) - a Garcinia kola seed extract containing a mixture of 5 flavonoids, in diabetes-induced nephrotoxic rats. Male Wistar rats were divided into 4 groups: untreated controls (C); normal rats treated with kolaviron (C+KV); untreated diabetic rats (D); kolaviron treated diabetic rats (D+KV). A single intraperitoneal injection of streptozotocin (STZ, 50mg/kg) was used for the induction of diabetes. Renal function parameters were estimated in a clinical chemistry analyzer. Markers of oxidative stress in the kidney homogenate were analyzed in a Multiskan Spectrum plate reader and Bio-plex Promagnetic bead-based assays was used for the analysis of inflammatory markers. The effect of kolaviron on diabetes-induced apoptosis was assessed by TUNEL assay. In the diabetic rats, alterations in antioxidant defenses such as an increase in lipid peroxidation, glutathione peroxidase (GPX) activity and a decrease in catalase (CAT) activity, glutathione (GSH) levels and oxygen radical absorbance capacity (ORAC) were observed. There was no difference in superoxide dismutase (SOD) activity. Diabetes induction increased apoptotic cell death and the levels of interleukin (IL)-1β and tumor necrosis factor (TNF)-α with no effect on IL-10. Kolaviron treatment of diabetic rats restored the activities of antioxidant enzymes, reduced lipid peroxidation and increased ORAC and GSH concentration in renal tissues. Kolaviron treatment of diabetic rats also suppressed renal IL-1β. The beneficial effects of kolaviron on diabetes-induced kidney injury may be due to its inhibitory action on oxidative stress, IL-1β production and apoptosis.

  1. Temporal Evolution of Volcanic and Plutonic Magmas Related to Porphyry Copper Ores Based on Zircon Geochemistry

    Science.gov (United States)

    Dilles, J. H.; Lee, R. G.; Wooden, J. L.; Koleszar, A. M.

    2015-12-01

    Porphyry Cu (Mo-Au) and epithermal Au-Ag ores are globally associated with shallow hydrous, strongly oxidized, and sulfur-rich arc intrusions. In many localities, long-lived magmatism includes evolution from early andesitic volcanic (v) and plutonic (p) rocks to later dacitic or rhyolitic compositions dominated by plutons. We compare zircon compositions from three igneous suites with different time spans: Yerington, USA (1 m.y., p>v), El Salvador, Chile (4 m.y., p>v), and Yanacocha, Peru (6 m.y., v>p). At Yerington granite dikes and ores formed in one event, at ES in 2 to 3 events spanning 3 m.y., and at Yanacocha in 6 events spanning 5 m.y. At both ES and Yanacocha, high-Al amphiboles likely crystallized at high temperature in the mid-crust and attest to deep magmas that periodically recharged the shallow chambers. At Yanacocha, these amphiboles contain anhydrite inclusions that require magmas were sulfur-rich and strongly oxidized (~NNO+2). The Ti-in-zircon geothermometer provides estimates of 920º to 620º C for zircon crystallization, and records both core to rim cooling and locally high temperature rim overgrowths. Ore-related silicic porphyries yield near-solidus crystallization temperatures of 750-650°C consistent with low zircon saturation temperatures. The latter zircons have large positive Ce/Ce* and small negative Eu/Eu*≥0.4 anomalies attesting to strongly oxidized conditions (Ballard et al., 2001), which we propose result from crystallization and SO2 loss to the magmatic-hydrothermal ore fluid (Dilles et al., 2015). The Hf, REE, Y, U, and Th contents of zircons are diverse in the magma suites, and Th/U vs Yb/Gd plots suggest a dominant role of crystal fractionation with lesser roles for both crustal contamination and mixing with high temperature deep-sourced mafic magma. Ce/Sm vs Yb/Gd plots suggest that magma REE contents at <900°C are dominated by early crystallization of hornblende and apatite, and late crystallization (~<780°C) of titanite

  2. The Shahewan rapakivi-textured granite – quartz monzonite pluton, Qinling orogen, central China: mineral composition and petrogenetic significance

    Directory of Open Access Journals (Sweden)

    Xiaoxia Wang

    2002-01-01

    Full Text Available The Mesozoic Shahewan pluton consists of four texturally different types of biotite-hornblende quartz monzonite. In the porphyritic types alkali feldspar occurs as euhedral or ovoidal megacrysts that are often mantled by one or more plagioclase shells, and as smaller grains in the groundmass. Quartz, plagioclase (An20–28, biotite, and hornblende occur as inclusions in the alkali feldspar megacrystsand, more abundantly, in the groundmass. Euhedral quartz crystals in the groundmass are not as common and well developed as in typical rapakivi granite. Compared to typical rapakivi granites, the mafic minerals (biotite and hornblende are rich in Mg and poor in Fe, and the whole rock is low in Si, K, F, Ga, Zr, LREE, Fe/Mg, and K/Na. The rocks of the Shahewan pluton are thus regarded as rapakivi-textured quartz monzonites and granites but not true rapakivi granites.

  3. The distribution, geochronology and geochemistry of early Paleozoic granitoid plutons in the North Altun orogenic belt, NW China: Implications for the petrogenesis and tectonic evolution

    Science.gov (United States)

    Meng, Ling-Tong; Chen, Bai-Lin; Zhao, Ni-Na; Wu, Yu; Zhang, Wen-Gao; He, Jiang-Tao; Wang, Bin; Han, Mei-Mei

    2017-01-01

    Abundant early Paleozoic granitoid plutons are widely distributed in the North Altun orogenic belt. These rocks provide clues to the tectonic evolution of the North Altun orogenic belt and adjacent areas. In this paper, we report an integrated study of petrological features, U-Pb zircon dating, in situ zircon Hf isotope and whole-rock geochemical compositions for the Abei, 4337 Highland and Kaladawan Plutons from north to south in the North Altun orogenic belt. The dating yielded magma crystallization ages of 514 Ma for the Abei Pluton, 494 Ma for the 4337 Highland Pluton and 480-460 Ma for the Kaladawan Pluton, suggesting that they are all products of oceanic slab subduction because of the age constraint. The Abei monzogranites derived from the recycle of Paleoproterozoic continental crust under low-pressure and high-temperature conditions are products of subduction initiation. The 4337 Highland granodiorites have some adakitic geochemical signatures and are sourced from partial melting of thickened mafic lower continental crust. The Kaladawan quartz diorites are produced by partial melting of mantle wedge according to the positive εHf(t) values, and the Kaladawan monzogranite-syenogranite are derived from partial melting of Neoproterozoic continental crust mixing the juvenile underplated mafic material from the depleted mantle. These results, together with existing data, provide significant information about the evolution history of oceanic crust subduction during the 520-460 Ma. The initiation of subduction occurred during 520-500 Ma with formation of Abei Pluton; subsequent transition from steep-angle to flat-slab subduction at ca.500 Ma due to the arrival of buoyant oceanic plateaus, which induces the formation of 4337 Highland Pluton. With ongoing subduction, the steep-angle subduction system is reestablished to cause the formation of 480-460 Ma Kaladawan Pluton. Meanwhile, it is this model that account for the temporal-spatial distribution of these early

  4. Ion-adsorption REEs in regolith of the Liberty Hill pluton, South Carolina, USA: An effect of hydrothermal alteration

    Science.gov (United States)

    Bern, Carleton R.; Yesavage, Tiffany; Foley, Nora K.

    2017-01-01

    Ion-adsorbed rare earth element (REE) deposits supply the majority of world heavy REE production and substantial light REE production, but relatively little is known of their occurrence outside Southeast Asia. We examined the distribution and forms of REEs on a North American pluton located in the highly weathered and slowly eroding South Carolina Piedmont. The Hercynian Liberty Hill pluton experiences a modern climate that includes ~ 1500 mm annual rainfall and a mean annual temperature of 17 °C. The pluton is medium- to coarse-grained biotite-amphibole granite with minor biotite granite facies. REE-bearing phases are diverse and include monazite, zircon, titanite, allanite, apatite and bastnäsite. Weathered profiles were sampled up to 7 m-deep across the ~ 400 km2 pluton. In one profile, ion-adsorbed REEs plus yttrium (REE + Y) ranged up to 581 mg/kg and accounted for up to 77% of total REE + Y in saprolite. In other profiles, ion-adsorbed REE + Y ranged 12–194 mg/kg and only accounted for 3–37% of totals. The profile most enriched in ion-adsorbed REEs was located along the mapped boundary of two granite facies and contained trioctahedral smectite in the saprolite, evidence suggestive of hydrothermal alteration of biotite at that location. Post-emplacement deuteric alteration can generate easily weathered REE phases, particularly fluorocarbonates. In the case of Liberty Hill, hydrothermal alteration may have converted less soluble to more soluble REE minerals. Additionally, regolith P content was inversely correlated with the fraction ion-adsorbed REEs, and weathering related secondary REE-phosphates were found in some regolith profiles. Both patterns illustrate how low P content aids in the accumulation of ion-adsorbed REEs. The localized occurrence at Liberty Hill sheds light on conditions and processes that generate ion-adsorbed REEs.

  5. The Ajo Mining District, Pima County, Arizona--Evidence for Middle Cenozoic Detachment Faulting, Plutonism, Volcanism, and Hydrothermal Alteration

    Science.gov (United States)

    Cox, Dennis P.; Force, Eric R.; Wilkinson, William H.; More, Syver W.; Rivera, John S.; Wooden, Joseph L.

    2006-01-01

    Introduction: The Ajo porphyry copper deposit and surrounding Upper Cretaceous rocks have been separated from their plutonic source and rotated by detachment faulting. Overlying middle Cenozoic sedimentary and volcanic rocks have been tilted and show evidence for two periods of rotation. Following these rotations, a granitic stock (23.7?0.2 Ma) intruded basement rocks west of the Ajo deposit. This stock was uplifted 2.5 km to expose deep-seated Na-Ca alteration.

  6. Single Zircon LA-ICP-MS U-Pb Dating of the Guandimiao and Wawutang Granitic Plutons in Hunan, South China and Its Petrogenetic Significance

    Institute of Scientific and Technical Information of China (English)

    CHEN Weifeng; CHEN Peirong; ZHOU Xinmin; HUANG Hongye; DING Xing; SUN Tao

    2007-01-01

    The Guandimao and Wawutang plutons are located at the center of Hunan, South China.The former is mainly composed of biotite monzonitic granites/granodiorites and two-mica monzonitic granites, but the latter only consists of biotite monzonitic granites. The zircon ages of 203.0±1.6 Ma (biotite monzonitic granites) and 208.0±3.2 Ma (two-mica monzonitic granites) for the Guandimao pluton and 204±3 Ma for the Wawutang pluton obtained with the LA-ICP-MS U-Pb dating indicate that they were formed during the late Indosinian. In consideration of other geochronological data from Indosinlan rocks of South China and adjacent regions, it is inferred that the two plutons were derived from crustal materials by decompressional melting in a post-collisional tectonic setting during spontaneous thinning of the thickened curst. Moreover, the inherited zircon age of 1273±k57 Ma from the Wawutang pluton indicates that the source of the two plutons is related to the early Proterozoic crustal basement.

  7. Contrasting magmatic structures between small plutons and batholiths emplaced at shallow crustal level (Sierras de Córdoba, Argentina)

    Science.gov (United States)

    Pinotti, Lucio P.; D'Eramo, Fernando J.; Weinberg, Roberto F.; Demartis, Manuel; Tubía, José María; Coniglio, Jorge E.; Radice, Stefania; Maffini, M. Natalia; Aragón, Eugenio

    2016-11-01

    Processes like injection, magma flow and differentiation and influence of the regional strain field are here described and contrasted to shed light on their role in the formation of small plutons and large batholiths their magmatic structures. The final geometric and compositional arrangement of magma bodies are a complex record of their construction and internal flow history. Magma injection, flow and differentiation, as well as regional stresses, all control the internal nature of magma bodies. Large magma bodies emplaced at shallow crustal levels result from the intrusion of multiple magma batches that interact in a variety of ways, depending on internal and external dynamics, and where the early magmatic, growth-related structures are commonly overprinted by subsequent history. In contrast, small plutons emplaced in the brittle-ductile transition more likely preserve growth-related structures, having a relatively simple cooling history and limited internal magma flow. Outcrop-scale magmatic structures in both cases record a rich set of complementary information that can help elucidate their evolution. Large and small granitic bodies of the Sierra Pampeanas preserve excellent exposures of magmatic structures that formed as magmas stepped through different rheological states during pluton growth and solidification. These structures reveal not only the flow pattern inside magma chambers, but also the rheological evolution of magmas in response to temperature evolution.

  8. [Discussion on diagenesis of Xilingang pluton-constrained by X-ray Fluorescence spectroscopy, plasma mass spectrometry and Raman spectroscopy].

    Science.gov (United States)

    Tang, Yu-Kun; Chen, Guo-Neng; Zhang, Ke; Huang, Hai-Hua

    2013-05-01

    The results on Xilingang pluton, mainly consisting of red beds, granites containing numerous debris of red beds and granites, obtained by X-ray fluorescence spectroscopy, plasma mass spectrometry and Raman spectroscopy show: (1) Xilingang pluton from red beds, granites containing numerous debris of red beds to granites has obvious characteristics of decreasing silicon and alkali content, and rising ignition loss, dark mineral content and oxidation index; (2) Chondrite-normalized REE distribution curves and primitive mantle-normalized spider diagram for trace elements of redbed, granites containing numerous debris of red beds and granites have a good consistency, the distribution characteristics of elements are similar to Nanling transformation-type granite; (3) The value of Raman spectrogram characteristic peak of quartz crystal in Xilingang granite decreased from the center of quartz crystal, and FWHM is steady. According to the above, the authors believe that Xilingang granite formed was related to in-situ melting of red beds and underlying strata and magma consolidation. Volatile components were discharged continuously, and oxidation index decreased gradually in the melting process. In the process of diagenesis, the top of pluton tend to be an ongoing silicon and alkali increase, while TFeO and MgO continue to migrate to bottom, and crystallization environment is a relatively closed and steady system.

  9. Carboniferous magmatism in the Evora Massif (southwest Portugal, Ossa-Morena Zone): from typical arc calc-alkaline to adakitic-like magmatism

    Science.gov (United States)

    Lima, Selma M.; Neiva, Ana M. R.; Ramos, Joao M. F.

    2014-05-01

    The Evora Massif is one of the subdivisions of western Ossa-Morena Zone. It is a dome-like structure mainly composed of Ediacaran, Cambrian and Ordovician country rocks, affected by medium- and high-grade metamorphism coeval with the emplacement of several mafic to felsic intrusive bodies. The last magmatic event recorded in this area (Carboniferous) consists of calc-alkaline volcanism and voluminous plutonism (mainly composed by tonalites, gabbros, diorites and late-orogenic granodiorites and granites) [1]. Detailed chemical and isotopic studies from Evora Massif plutons were performed in the last few years. Whole-rock chemical and isotopic data suggest that the Hospitais tonalite (HT), Alto de Sao Bento area (ASB) and Reguengos de Monsaraz pluton (RM) resulted from fractional crystallization of mantle-derived magmas followed by mixing with variable proportions of crustal melts [2-4]. U-Pb ID-TIMS data indicate an age of 337-335 for the RM [4]. The Pavia pluton is a multiphase granitic body constructed incrementally by the episodic emplacement of several batches of magma (at 328 Ma, ca. 324 Ma and 319-317 Ma) [5]. The main granitic phases range from tonalite to two-mica granite that contain rare surmicaceous and fine-grained enclaves, and granitic and amphibolitic xenoliths. On the other hand, they are cut by abundant rhyodacite porphyries, microgranites (s.l.) and pegmatite dikes, predominantly oriented NE-SW and NW-SE. Although each phase seems to represent a distinct batch of magma, whole-rock Sr-Nd isotopic data suggest a similar and fairly homogenous source for all the constituent phases. Initial 87Sr/86Sr varies between 0.70428 and 0.7058 and ɛ Ndt ranges from -3.4 to +0.4, pointing towards a mantle or juvenile crust origin. A higher variation is observed in whole-rock δ18O (5.6-9.6 o), consistent with assimilation of crust. The PP was interpreted as the result of assimilation-fractional crystallization of a basaltic magma. Substantial differences between

  10. Fission Track Geochronology of Xiaonanchuan Pluton and the Morphotectonic Evolution of Eastern Kunlun since Late Miocene

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Apatite fission track (AFT) thermochronology of seven samples from the Xiaonanchuan(小南川) pluton in the Kunlun (昆仑) pass area was carried out, for the purpose of determining the timing of cooling and the relation between the exhumation and the morphotectonic processes. The AFT ages yield low denudation rates of 0.020-0.035 mm/ a during the late Miocene, which correspond to a stable geomorphic and weak tectonic uplifting environment. The low denudation rates can be considered as the approximate tectonic uplifting rates. The AFT geochronology shows paroxysmally rapid cooling since the Pliocene and an apparent material unroofing of more than 3 km in the Xiaonanchuan area. This was not the result of simple denudation. The rapid cooling was coupled with the intensive orogeny since the Pliocene, which was driven by tectonic uplifting. The accelerated relief building was accompanied by a series of faulting, which caused the basin and the valley formation and sinking. The space pattern of the AFT ages also shows differential uplifting, which decreases northwardly. This trend is supported by the regional AFT data, which indicate that the exhumation decreases northwardly in eastern Kunlun. This trend also exists in east-west orientation from the western Kunlun range to the eastern. The uplifting trend is also supported by geomorphic characteristics including the elevation and the relief differences as well as the distribution of the Late Cenozoic volcanism.

  11. Formation of lower continental crust by relamination of buoyant arc lavas and plutons

    Science.gov (United States)

    Kelemen, Peter B.; Behn, Mark D.

    2016-03-01

    The formation of the Earth's continents is enigmatic. Volcanic arc magmas generated above subduction zones have geochemical compositions that are similar to continental crust, implying that arc magmatic processes played a central role in generating continental crust. Yet the deep crust within volcanic arcs has a very different composition from crust at similar depths beneath the continents. It is therefore unclear how arc crust is transformed into continental crust. The densest parts of arc lower crust may delaminate and become recycled into the underlying mantle. Here we show, however, that even after delamination, arc lower crust still has significantly different trace element contents from continental lower crust. We suggest that it is not delamination that determines the composition of continental crust, but relamination. In our conceptual model, buoyant magmatic rocks generated at arcs are subducted. Then, upon heating at depth, they ascend and are relaminated at the base of the overlying crust. A review of the average compositions of buoyant magmatic rocks -- lavas and plutons -- sampled from the Aleutians, Izu-Bonin-Marianas, Kohistan and Talkeetna arcs reveals that they fall within the range of estimated major and trace elements in lower continental crust. Relamination may thus provide an efficient process for generating lower continental crust.

  12. The intrusive complexof the Island of Giglio: geomagnetic characteristics of plutonic facies with low susceptibility contrast

    Directory of Open Access Journals (Sweden)

    R. Cavallini

    1998-06-01

    Full Text Available Two main plutonic facies characterize the intrusive complex of the Island of Giglio, and the trend of their contact at depth has been modelled using a 2D½ analysis based on a detailed geomagnetic survey in order to verify the geological hypothesis of the subsurface geometry of this contact. The magnetic anomaly connected with the discontinuity is quite low, due to the small difference between the magnetic susceptibilities of the two granitic facies. Development of this model of inversion of the magnetic field, which is in good agreement with the geological interpretation, was made possible by: 1 accurate control of the geomagnetic time variations and consequent temporal reduction, 2 a very low level of the artificial magnetic noise, 3 high density of the magnetic survey, 4 detailed knowledge of the mapped geologic contact between facies and of their petrologic characteristics, and 5 direct local measurements of the magnetic susceptibilities of the key lithologies. The model shows the trends of the geological contact, as projected in three E-W sections, that dips eastward in the range between 210 and 540, supporting the geologic hypothesis that the Pietrabona facies represents an external shell of the shallowly emplaced Giglio monzogranite intrusion.

  13. Natural radionuclides in the rocks of the Valle del Cervo Pluton in Piedmont.

    Science.gov (United States)

    Sesana, Lucia; Fumagalli, Marco; Carnevale, Mauro; Polla, Giancarla; Facchini, Ugo; Colombo, Annita; Tunesi, Annalisa; De Capitani, Luisa; Rusconi, Rosella

    2006-01-01

    Monitoring of the gamma radiation in Valle del Cervo Pluton was performed by determining U and Th contents in the main rock types cropping out over the entire area and pertaining to the granitic complex, syenitic complex and monzonitic complex. In particular, syenitic rocks were largely used as building and ornamental materials (e.g. Sienite della Balma). All the samples are fresh and do not present joints or fractures filled with U minerals. In the crushed samples the activity of uranium varies from 346 to 764 Bq/kg. Concentration of thorium varies from 202 to 478 Bq/kg. For all the analysed rocks uranium activity is higher than thorium one. The lowest value of radioactive concentration is referred to rocks of the granitic complex. The most active rocks are syenites. The data confirm the high activities of Valle del Cervo rock types, strongly connected with high K content of the source magma (geochemical signature); on the contrary, the activity seems to be not related to the location of the samples.

  14. Comparison between several multi-parameter seismic inversion methods in identifying plutonic igneous rocks

    Institute of Scientific and Technical Information of China (English)

    Yang Haijun; Xu Yongzhong; Huang Zhibin; Chen Shizhong; Yang Zhilin; Wu Gang; Xiao Zhongyao

    2011-01-01

    With the objective of establishing the necessary conditions for 3-D seismic data from a Permian plutonic oilfield in western China,we compared the technology of several multi-parameter seismic inversion methods in identifying igneous rocks.The most often used inversion methods are Constrained Sparse Spike Inversion (CSSI).Artificial Neural Network Inversion (ANN) and GR Pseudo-impedance Inversion.Through the application of a variety of inversion methods with log curves correction,we obtained relatively high-resolution impedance and velocity sections,effectively identifying the lithology of Permian igneous rocks and inferred lateral variation in the lithology of tgneous rocks.By means of a comprehensive comparative study,we arrived at the following conclusions:the CSSI inversion has good waveform continuity,and the ANN inversion has lower resolution than the CSSI inversion.The inversion results show that multi-parameter seismic inversion methods are an effective solution to the identification of igneous rocks.

  15. Young cumulate complex beneath Veniaminof caldera, Aleutian arc, dated by zircon in erupted plutonic blocks

    Science.gov (United States)

    Bacon, Charles R.; Sisson, Thomas W.; Mazdab, Frank K.

    2007-06-01

    Mount Veniaminof volcano, Alaska Peninsula, provides an opportunity to relate Quaternary volcanic rocks to a coeval intrusive complex. Veniaminof erupted tholeiitic basalt through dacite in the past ˜260 k.y. Gabbro, diorite, and miarolitic granodiorite blocks, ejected 3700 14C yr B.P. in the most recent caldera-forming eruption, are fragments of a shallow intrusive complex of cumulate mush and segregated vapor-saturated residual melts. Sensitive high-resolution ion microprobe (SHRIMP) analyses define 238U-230Th isochron ages of 17.6 ± 2.7 ka, 5 +11/-10 ka, and 10.2 ± 4.0 ka (2σ) for zircon in two granodiorites and a diorite, respectively. Sparse zircons from two gabbros give 238U-230Th model ages of 36 ± 8 ka and 26 ± 7 ka. Zircons from granodiorite and diorite crystallized in the presence of late magmatic aqueous fluid. Although historic eruptions have been weakly explosive Strombolian fountaining and small lava effusions, the young ages of plutonic blocks, as well as late Holocene dacite pumice, are evidence that the intrusive complex remains active and that evolved magmas can segregate at shallow levels to fuel explosive eruptions.

  16. [Alkaline phosphatase in Amoeba proteus].

    Science.gov (United States)

    Sopina, V A

    2005-01-01

    In free-living Amoeba proteus (strain B), 3 phosphatase were found after disc-electrophoresis of 10 microg of protein in PAGE and using 1-naphthyl phosphate as a substrate a pH 9.0. These phosphatases differed in their electrophoretic mobilities - "slow" (1-3 bands), "middle" (one band) and "fast" (one band). In addition to 1-naphthyl phosphate, "slow" phosphatases were able to hydrolyse 2-naphthyl phosphate and p-nitrophenyl phosphate. They were slightly activated by Mg2+, completely inhibited by 3 chelators (EDTA, EGTA and 1,10-phenanthroline), L-cysteine, sodium dodecyl sulfate and Fe2+, Zn2+ and Mn2+ (50 mM), considerably inactivated by orthovanadate, molybdate, phosphatase inhibitor cocktail 1, p-nitrophenyl phosphate, Na2HPO4, DL-dithiothreitol and urea and partly inhibited by H2O2, DL-phenylalanine, 2-mercaptoethanol, phosphatase inhibitor cocktail 2 and Ca2+. Imidazole, L-(+)-tartrate, okadaic acid, NaF and sulfhydryl reagents -p-(hydroxy-mercuri)benzoate and N-ethylmaleimide - had no influence on the activity of "slow" phosphatases. "Middle" and "fast" phosphatases, in contrast to "slow" ones, were not inactivated by 3 chelators. The "middle" phosphatase differed from the "fast" one by smaller resistance to urea, Ca2+, Mn2+, phosphates and H2O2 and greater resistance to dithiothreitol and L-(+)-tartrate. In addition, the "fast" phosphatase was inhibited by L-cysteine but the "middle" one was activated by it. Of 5 tested ions (Mg2+, Cu2+, Mn2+, Ca2+ and Zn2+), only Zn2+ reactivated "slow" phosphatases after their inactivation by EDTA treatment. The reactivation of apoenzyme was only partial (about 35 %). Thus, among phosphatases found in amoebae at pH 9.0, only "slow" ones are Zn-metalloenzymes and may be considered as alkaline phosphatases (EC 3.1.3.1). It still remains uncertain, to which particular phosphatase class "middle" and "fast" phosphatases (pH 9.0) may belong.

  17. E-microsatellite markers for Centella asiatica (Gotu Kola) genome: validation and cross-transferability in Apiaceae family for plant omics research and development.

    Science.gov (United States)

    Sahu, Jagajjit; Das Talukdar, Anupam; Devi, Kamalakshi; Choudhury, Manabendra Dutta; Barooah, Madhumita; Modi, Mahendra Kumar; Sen, Priyabrata

    2015-01-01

    Abstract Centella asiatica (Gotu Kola) is a plant that grows in tropical swampy regions of the world and has important medicinal and culinary use. It is often considered as part of Ayurvedic medicine, traditional African medicine, and traditional Chinese medicine. The unavailability of genomics resources is significantly impeding its genetic improvement. To date, no attempt has been made to develop Expressed Sequence Tags (ESTs) derived Simple Sequence Repeat (SSR) markers (eSSRs) from the Centella genome. Hence, the present study aimed to develop eSSRs and their further experimental validation and cross-transferability of these markers in different genera of the Apiaceae family to which Centella belongs. An in-house pipeline was developed for the entire analyses by combining bioinformatics tools and perl scripts. A total of 4443 C. asiatica EST sequences from dbEST were processed, which generated 2617 nonredundant high quality EST sequences consisting 441 contigs and 2176 singletons. Out of 1776.5 kb of examined sequences, 417 (15.9%) ESTs containing 686 SSRs were detected with a density of one SSR per 2.59 kb. The gene ontology study revealed 282 functional domains involved in various processes, components, and functions, out of which 64 ESTs were found to have both SSRs and functional domains. Out of 603 designed EST-SSR primers, 18 pairs of primers were selected for validation based on the optimum parameter value. Reproducible amplification was obtained for six primer pairs in C. asiatica that were further tested for cross-transferability in nine other important genera/species of the Apiaceae family. Cross-transferability of the EST-SSR markers among the species were examined and Centella javanica showed highest transferability (83.3%). The study revealed six highly polymorphic EST-SSR primers with an average PIC value of 0.95. In conclusion, these EST-SSR markers hold a big promise for the genomics analysis of Centella asiatica, to facilitate comparative

  18. Prophylactic treatment with alkaline phosphatase in cardiac surgery induces endogenous alkaline phosphatase release

    NARCIS (Netherlands)

    Kats, Suzanne; Brands, Ruud; Hamad, Mohamed A. Soliman; Seinen, Willem; Schamhorst, Volkher; Wulkan, Raymond W.; Schoenberger, Jacques P.; van Oeveren, Wim

    2012-01-01

    Introduction: Laboratory and clinical data have implicated endotoxin as an important factor in the inflammatory response to cardiopulmonary bypass. We assessed the effects of the administration of bovine intestinal alkaline phosphatase (bIAP), an endotoxin detoxifier, on alkaline phosphatase levels

  19. Uptake of arsenic by alkaline soils near alkaline coal fly ash disposal facilities.

    Science.gov (United States)

    Khodadoust, Amid P; Theis, Thomas L; Murarka, Ishwar P; Naithani, Pratibha; Babaeivelni, Kamel

    2013-12-01

    The attenuation of arsenic in groundwater near alkaline coal fly ash disposal facilities was evaluated by determining the uptake of arsenic from ash leachates by surrounding alkaline soils. Ten different alkaline soils near a retired coal fly ash impoundment were used in this study with pH ranging from 7.6 to 9.0, while representative coal fly ash samples from two different locations in the coal fly ash impoundment were used to produce two alkaline ash leachates with pH 7.4 and 8.2. The arsenic found in the ash leachates was present as arsenate [As(V)]. Adsorption isotherm experiments were carried out to determine the adsorption parameters required for predicting the uptake of arsenic from the ash leachates. For all soils and leachates, the adsorption of arsenic followed the Langmuir and Freundlich equations, indicative of the favorable adsorption of arsenic from leachates onto all soils. The uptake of arsenic was evaluated as a function of ash leachate characteristics and the soil components. The uptake of arsenic from alkaline ash leachates, which occurred mainly as calcium hydrogen arsenate, increased with increasing clay fraction of soil and with increasing soil organic matter of the alkaline soils. Appreciable uptake of arsenic from alkaline ash leachates with different pH and arsenic concentration was observed for the alkaline soils, thus attenuating the contamination of groundwater downstream of the retired coal fly ash impoundment.

  20. The Fractal Behavior of Crystal Distribution of la Gloria Pluton, Chile

    Science.gov (United States)

    Gutiérrez, F. J.; Payacán, I. J.; Pasten, D.; Aravena, A.; Gelman, S. E.; Bachmann, O.; Parada, M. A.

    2013-12-01

    We utilize fractal analysis to study the spatial distributions of crystals in a 10 Ma granitic intrusion (La Gloria pluton) located in the central Chilean Andes. Previous work determined the crystal size distribution (CSD) and anisotropy of magnetic susceptibility (AMS) tensors throughout this pluton. Using orthogonal thin sections oriented along the AMS tensor axes, we have applied fractal analysis in three magmatic crystal families: plagioclase, ferromagnesian minerals (biotite and amphibole), and Fe-Ti oxides (magnetite with minor ilmenite). We find that plagioclase and ferromagnesian minerals have a Semi-logarithmic CSD (S-CSD), given by: log(n/n0)= -L/C (1) where n [mm-4], n0 [mm-4], L [mm] and C [mm] are crystal density, intercept (nucleation density; L=0), size of crystals (three axes) and characteristic length, respectively. In contrast, Fe-Ti oxides have a Fractal CSD (F-CSD, power law size distribution), given by: log(n)= - Dn log(L) + n1 (2) where Dn and n1 [log(mm-4)] are a non-dimensional proportionality constant and the logarithm of the initial crystallization density (n1 = log(n(L=1 mm))), respectively. Finally, we calculate the fractal dimension (D0) by applying the box-counting method on each crystal thin section image, using: log(N) = -D0 log(ɛ) (3) where N and ɛ are the number of boxes occupied by minerals and the length of the square box, respectively. Results indicate that D0 values (eq. 3) are well defined for all minerals, and are higher for plagioclase than for ferromagnesian minerals and lowest for Fe-Ti oxides. D0 values are correlated with n0 and -1/C for S-CSD (eq. 1), and with n1 values for F-CSD (eq. 2). These correlations between fractal dimensions with CSD parameters suggest crystal growth follows a fractal behaviour in magmatic systems. Fractal behaviour of CSD means that the spatial distribution of crystals follows an all-scale pattern as part of a self-organized magmatic system. We interpret S-CSD of plagioclase and

  1. Growth of a Large Composite Magma System: the EJB Pluton, Eastern California.

    Science.gov (United States)

    Matty, D. J.; Vervoort, J.; Dufrane, A.; Hart, G.; Student, J.; Morgan, S.

    2008-12-01

    The composite EJB pluton crops out in the White-Inyo Mountains of eastern California, and comprises the Eureka Valley monzonite (EVM), the Joshua Flat quartz monzonite (JFQM), the Beer Creek granite (BCG), and an unnamed diorite. While sometimes equivocal, field relationships suggest that the EVM was emplaced first, followed by the JFQM, and finally the BCG; the diorite predates the BCG. Sylvester and others (GSAB, 1978) reported zircon U-Pb ages of 179±2 Ma for the EVM and 174±5 Ma for the JFQM. Coleman and others (GSAB, 2003) determined a U-Pb age of 179±3 Ma (via Pb-loss trajectory) for the BCG. Because of the uncertainty in the ages and ambiguous field relations, the sequence and duration of EJB magmatism remain unclear. To understand more fully the timing of EJB magmatism, we separated zircons from 12 samples collected from each of the main EJB units. These samples were characterized using light microscopy, SEM and CL techniques. U-Pb ages were determined from individual zircons by LA-ICP-MS following the method of Chang and others (G3, 2006). For the ages reported below, the reported uncertainties are based on factors within the analysis, but do not include external factors such as sample/standard bias or other matrix effects. Overall uncertainty in LA-ICPMS U-Pb geochronology is hard to assess, but we estimate that all ages reported below are subject to a minimum 2% uncertainty. We determined a concordant U-Pb age of 180±2 Ma for the EVM, which agrees with the results of Sylvester and others (1978). The unnamed diorite produced a concordant U-Pb age of 177±3 Ma. Concordant U-Pb ages of 172±2, 172±3, 173±2, 174±2, and 175±2 Ma were determined for individual samples of the JFQM and agree with the age reported by Sylvester and others (1978) of 174±5 Ma. Concordant U-Pb ages of 168±4, 168±3, 169±1, 172±2, and 172±2 Ma were determined for individual BCG samples. Within the reported error, there is no difference in age between individual samples of

  2. Multi-sensor geophysical constraints on crustal melt in the central Andes: the PLUTONS project

    Science.gov (United States)

    Pritchard, M. E.; Comeau, M. J.; West, M. E.; Christensen, D. H.; Mcfarlin, H. L.; Farrell, A. K.; Del Potro, R.; Gottsmann, J.; McNutt, S. R.; Michelfelder, G.; Diez, M.; Elliott, J.; Henderson, S. T.; Keyson, L.; Delgado, F.; Unsworth, M. J.

    2015-12-01

    The central Andes is a key global location to quantify storage, transport, and volumes of magma in the Earth's crust as it is home to the world's largest zone of partial melt (the Altiplano-Puna Magma or Mush Body, APMB) as well as the more recently documented Southern Puna Magma Body (SPMB). We describe results from the recently completed international PLUTONS project that focused inter-disciplinary study on two sites of large-scale surface uplift that presumably represent ongoing magmatic intrusions in the mid to upper crust - Uturuncu, Bolivia (in the center of the APMB) and Lazufre on the Chile-Argentina border (on the edge of the SPMB). In particular, a suite of geophysical techniques (seismology, gravity, surface deformation, and electro-magnetic methods) have been used to infer the current subsurface distribution and quantity of partial melts in combination with geochemical and lab studies on samples from the area. Both Uturuncu and Lazufre show separate geophysical anomalies in the upper and mid/lower crust (e.g., low seismic velocity, low resistivity, etc.) indicating multiple distinct reservoirs of magma and/or hydrothermal fluids with different properties. The characteristics of the geophysical anomalies differ somewhat depending on the technique used - reflecting the different sensitivity of each method to subsurface melt of different compositions, connectivity, and volatile content. For example, the depth to the top of the APMB is shallower in a joint ambient noise tomography and receiver function analysis compared to a 3D magnetotelluric inversion. One possibility is that the seismic methods are detecting brines above the APMB that do not have a large electromagnetic signature. Comparison of the geophysical measurements with laboratory experiments at the APMB indicate a minimum of 4-25% melt averaged over the region is needed -- higher melt volumes are permitted by the gravity and MT data and may exist in small regions. However, bulk melt values above

  3. Geologic and hydrologic controls on the economic potential of hydrothermal systems associated with upper crustal plutons

    Science.gov (United States)

    Weis, Philipp; Driesner, Thomas; Scott, Samuel; Lecumberri-Sanchez, Pilar

    2016-04-01

    Heat and mass transport in hydrothermal systems associated with upper crustal magmatic intrusions can result in resources with large economic potential (Kesler, 1994). Active hydrothermal systems can form high-enthalpy geothermal reservoirs with the possibility for renewable energy production. Fossil continental or submarine hydrothermal systems may have formed ore deposits at variable crustal depths, which can be mined near today's surface with an economic profit. In both cases, only the right combination of first-order geologic and hydrologic controls may lead to the formation of a significant resource. To foster exploration for these hydrothermal georesources, we need to improve our understanding of subsurface fluxes of mass and energy by combining numerical process modelling, observations at both active and fossil systems, as well as knowledge of fluid and rock properties and their interactions in natural systems. The presentation will highlight the role of non-linear fluid properties, phase separation, salt precipitation, fluid mixing, permeability structure, hydraulic fracturing and the transition from brittle to ductile rock behavior as major geologic and hydrologic controls on the formation of high-enthalpy and supercritical geothermal resources (Scott et al., 2015), and magmatic-hydrothermal mineral resources, such as porphyry copper, massive sulfide and epithermal gold deposits (Lecumberri-Sanchez et al., 2015; Weis, 2015). References: Kesler, S. E., 1994: Mineral Resources, economics and the environment, New York, McMillan, 391. Lecumberri-Sanchez, P., Steele-MacInnis, M., Weis, P., Driesner, T., Bodnar, R.J. (2015): Salt precipitation in magmatic-hydrothermal systems associated with upper crustal plutons. Geology, v. 43, p. 1063-1066, doi:10.1130/G37163.1 Scott, S., Driesner, T., Weis, P. (2015): Geologic controls on supercritical geothermal resources above magmatic intrusions. Nature Communications, 6:7837 doi: 10.1038/ncomms8837 Weis, P. (2015): The

  4. Polychronous (Early Cretaceous to Palaeogene) emplacement of the Mundwara alkaline complex, Rajasthan, India: 40Ar/39Ar geochronology, petrochemistry and geodynamics

    Science.gov (United States)

    Pande, Kanchan; Cucciniello, Ciro; Sheth, Hetu; Vijayan, Anjali; Sharma, Kamal Kant; Purohit, Ritesh; Jagadeesan, K. C.; Shinde, Sapna

    2016-07-01

    The Mundwara alkaline plutonic complex (Rajasthan, north-western India) is considered a part of the Late Cretaceous-Palaeogene Deccan Traps flood basalt province, based on geochronological data (mainly 40Ar/39Ar, on whole rocks, biotite and hornblende). We have studied the petrology and mineral chemistry of some Mundwara mafic rocks containing mica and amphibole. Geothermobarometry indicates emplacement of the complex at middle to upper crustal levels. We have obtained new 40Ar/39Ar ages of 80-84 Ma on biotite separates from mafic rocks and 102-110 Ma on whole-rock nepheline syenites. There is no evidence for excess 40Ar. The combined results show that some of the constituent intrusions of the Mundwara complex are of Deccan age, but others are older and unrelated to the Deccan Traps. The Mundwara alkaline complex is thus polychronous and similar to many alkaline complexes around the world that show recurrent magmatism, sometimes over hundreds of millions of years. The primary biotite and amphibole in Mundwara mafic rocks indicate hydrous parental magmas, derived from hydrated mantle peridotite at relatively low temperatures, thus ruling out a mantle plume. This hydration and metasomatism of the Rajasthan lithospheric mantle may have occurred during Jurassic subduction under Gondwanaland, or Precambrian subduction events. Low-degree decompression melting of this old, enriched lithospheric mantle, due to periodic diffuse lithospheric extension, gradually built the Mundwara complex from the Early Cretaceous to Palaeogene time.

  5. The evolution of Neoproterozoic magmatism in Southernmost Brazil: shoshonitic, high-K tholeiitic and silica-saturated, sodic alkaline volcanism in post-collisional basins

    Directory of Open Access Journals (Sweden)

    Sommer Carlos A.

    2006-01-01

    Full Text Available The Neoproterozoic shoshonitic and mildly alkaline bimodal volcanism of Southernmost Brazil is represented by rock assemblages associated to sedimentary successions, deposited in strike-slip basins formed at the post-collisional stages of the Brasilian/Pan-African orogenic cycle. The best-preserved volcano sedimentary associations occur in the Camaquã and Campo Alegre Basins, respectively in the Sul-riograndense and Catarinense Shields and are outside the main shear belts or overlying the unaffected basement areas. These basins are characterized by alternation of volcanic cycles and siliciclastic sedimentation developed dominantly on a continental setting under subaerial conditions. This volcanism and the coeval plutonism evolved from high-K tholeiitic and calc-alkaline to shoshonitic and ended with a silica-saturated sodic alkaline magmatism, and its evolution were developed during at least 60 Ma. The compositional variation and evolution of post-collisional magmatism in southern Brazil are interpreted as the result mainly of melting of a heterogeneous mantle source, which includes garnet-phlogopite-bearing peridotites, veined-peridotites with abundant hydrated phases, such as amphibole, apatite and phlogopite, and eventually with the addition of an asthenospheric component. The subduction-related metasomatic character of post-collisional magmatism mantle sources in southern Brazil is put in evidence by Nb-negative anomalies and isotope features typical of EM1 sources.

  6. Some durability aspects of hybrid alkaline cements

    Directory of Open Access Journals (Sweden)

    Donatello S.

    2014-04-01

    Full Text Available Blended cements that contain a high content of fly ash and a low content of Portland cement typically suffer from low early strength development and long setting times. Recently, one method of overcoming these problems has been to use an alkali activator to enhance the reactivity of fly ash particles at early ages. Such cements can be grouped under the generic term “hybrid alkaline cements”, where both cement clinker and fly ash, encouraged by the presence of alkalis, are expected to contribute to cementitious gel formation. The work presented here examines some of the durability aspects of high fly ash content hybrid alkaline cement. Specifically, the aspects investigated were: exposure at high temperatures (up to 1000°C, resistance to immersion in aggressive solutions and susceptibility to the alkali aggregate reaction. All tests were repeated with a commercially available sulfate resistant Portland cement for comparison. When exposed to high temperatures, the hybrid alkaline cement showed strikingly different behaviour compared to the control Portland cement, showing fewer micro-cracks and maintaining residual compressive strengths at least equal to original strengths. Beyond 700°C, the hybrid alkaline cement began to sinter, which resulted in shrinkage of around 5% and a 100% increase in residual compressive strengths. No such sintering event was noted in the control Portland cement, which showed a drastic loss in residual compressive strengths upon heating. In immersion tests, the hybrid alkaline cement possessed excellent resistance to sulfate and seawater attack, similar to the control sulfate resistant cement. Both cements were however severely degraded by immersion in 0.1M HCl for 90 days. Both binders complied with the accelerated alkali-aggregate test but when this test was extended, the hybrid alkaline binder showed much greater dimensional stability. Possible reasons for the differences in durability behaviour in both cements

  7. Alkaline Capacitors Based on Nitride Nanoparticles

    Science.gov (United States)

    Aldissi, Matt

    2003-01-01

    High-energy-density alkaline electrochemical capacitors based on electrodes made of transition-metal nitride nanoparticles are undergoing development. Transition- metal nitrides (in particular, Fe3N and TiN) offer a desirable combination of high electrical conductivity and electrochemical stability in aqueous alkaline electrolytes like KOH. The high energy densities of these capacitors are attributable mainly to their high capacitance densities, which, in turn, are attributable mainly to the large specific surface areas of the electrode nanoparticles. Capacitors of this type could be useful as energy-storage components in such diverse equipment as digital communication systems, implanted medical devices, computers, portable consumer electronic devices, and electric vehicles.

  8. Electrochemical behaviour of alkaline copper complexes

    Indian Academy of Sciences (India)

    C L Aravinda; S M Mayanna; V R Muralidharan

    2000-10-01

    A search for non-cyanide plating baths for copper resulted in the development of alkaline copper complex baths containing trisodium citrate [TSC] and triethanolamine [TEA]. Voltammetric studies were carried out on platinum to understand the electrochemical behaviour of these complexes. In TSC solutions, the deposition of copper involves the slow formation of a monovalent species. Adsorption of this species obeys Langmuir isotherm. In TEA solutions the deposition involves the formation of monovalent ions obeying the non-activated Temkin isotherm. Conversion of divalent to monovalent copper is also slow. In TEA and TSC alkaline copper solutions, the predominant species that undergo stepwise reduction contain only TEA ligands

  9. Interaction of the lithospheric mantle and crustal melts for the generation of the Horoz pluton (Niğde, Turkey: whole-rock geochemical and Sr–Nd–Pb isotopic evidence

    Directory of Open Access Journals (Sweden)

    Kerim Kocak

    2016-08-01

    Full Text Available The Horoz pluton includes granitic and granodioritic rocks, with widespread mafic microgranular enclaves (MMEs. Petrochemically, the rocks of the pluton show calc-alkaline to shoshonitic and metaluminous to slightly peraluminous composition. The rocks also exhibit an enrichment in large ion lithophile elements, e.g. Rb, K, and depletions of high field strength elements such as Y, Lu, and Mg#, Ni, with a slightly concave-upward rare earth element pattern. Both granitic and granodioritic rocks exhibit geochemical characteristics of tonalite, trondhjemite and granodiorite assemblages, possibly developed by the partial melting of a thickened lower crust. The granitoids have high concentrations of Na2O (2.6–4.5 wt%, Sr (347–599 ppm, intermediate-high (La/YbN (8.2–18.1, mostly >11 , Al2O3 (13.2–16.9 wt%, average 15.3 wt%, low MgO (0.2–1.4 wt%, average 0.84 wt% and Co (0.7–10.3 ppm. The MMEs include higher Na2O (4.5–5.5 wt%, Sr (389–1149 ppm, Al2O3 (16.9–19.2 wt%, average 17.8 wt%, MgO (1.4–4.4 wt%, average 2.75 wt% and Co (6.2–18.7 ppm contents in comparison with that of their hosts. There is a lack of negative Eu anomalies, except a few samples. Both host rocks and MMEs have a low initial 87Sr/86Sr ratio (respectively 0.7046–0.7051 and 0.7047–0.7058, low eNd value (–1.8 to –0.2 and –0.6 to 0.7 at 50 Ma and highly radiogenic 208Pb/204Pb ratios (39.43–39.47 and 39.39–39.54. Whole-rock chemistry and isotopic data suggest that parent magmas of both MMEs and their hosts have derived from melts of the mixing between the lithospheric mantle and crustal end members, than fractional crystallization processes in crustal levels.

  10. 3.30 Ga high-silica intraplate volcanic-plutonic system of the Gavião Block, São Francisco Craton, Brazil: Evidence of an intracontinental rift following the creation of insulating continental crust

    Science.gov (United States)

    Zincone, Stefano A.; Oliveira, Elson P.; Laurent, Oscar; Zhang, Hong; Zhai, Mingguo

    2016-12-01

    High-silica rhyolites having U-Pb zircon ages of 3303 ± 11 Ma occur along the eastern border of the Gavião Block (Brazil) associated with the Contendas-Mirante and Mundo Novo supracrustal belts. Unlike many Archean greenstone sequences, they are not interlayered with mafic to intermediate units. Instead, they belong to an inter-related plutonic-volcanic system, together with granitic massifs having similar zircon crystallization ages of ca. 3293 ± 3 Ma and 3328 ± 3 Ma and plotting along the same geochemical trends as the rhyolites. The rhyolites show well-preserved primary volcanic features such as magma flow textures and euhedral phenocrysts. High emplacement temperatures are indicated by petrographic evidence (β-quartz phenocrysts), zircon saturation temperatures (915-820 °C) and geochemical data, especially high SiO2 (74-79 wt.%) together with elevated Fe2O3(T) ( 3 wt.%), MgO (0.5-1.5 wt.%) and low Al2O3 (extraction and eruption of highly silicic residual liquid formed by crystallization of granitic magma in a relatively shallow (< 10 km) reservoir, now represented by the granite massifs. The granite magma was formed by melting or differentiation of material similar to the diorite gneiss that occurs regionally. The 3.30 Ga volcanic-plutonic systems formed after a period of crustal growth and stabilization of a thick continental lithosphere, represented by massive 3.40-3.33 Ga TTG and medium to high-K calk-alkaline magmatism in the Gavião Block. The 3.30 Ga-old rhyolites and granites would therefore have formed in an intracontinental tectonic setting after the formation and stabilization of new continental crust, and accordingly would represent the first stages of rifting and continental break-up. Intraplate magmatism and intracrustal differentiation processes took place on Earth at 3.3 Ga and produced magmas that were distinct from Archean TTGs, questioning the reliability (or at least the uniqueness) of "intraplate models" to explain the origin of the

  11. Plutonic xenoliths from Martinique, Lesser Antilles: evidence for open system processes and reactive melt flow in island arc crust

    Science.gov (United States)

    Cooper, George F.; Davidson, Jon P.; Blundy, Jon D.

    2016-10-01

    The Lesser Antilles Volcanic Arc is remarkable for the abundance and variety of erupted plutonic xenoliths. These samples provide a window into the deeper crust and record a more protracted crystallisation history than is observed from lavas alone. We present a detailed petrological and in situ geochemical study of xenoliths from Martinique in order to establish their petrogenesis, pre-eruptive storage conditions and their contribution to construction of the sub-volcanic arc crust. The lavas from Martinique are controlled by crystal-liquid differentiation. Amphibole is rarely present in the erupted lavas, but it is a very common component in plutonic xenoliths, allowing us to directly test the involvement of amphibole in the petrogenesis of arc magmas. The plutonic xenoliths provide both textural and geochemical evidence of open system processes and crystal `cargos'. All xenoliths are plagioclase-bearing, with variable proportions of olivine, spinel, clinopyroxene, orthopyroxene and amphibole, commonly with interstitial melt. In Martinique, the sequence of crystallisation varies in sample type and differs from other islands of the Lesser Antilles arc. The compositional offset between plagioclase (~An90) and olivine (~Fo75), suggests crystallisation under high water contents and low pressures from an already fractionated liquid. Texturally, amphibole is either equant (crystallising early in the sequence) or interstitial (crystallising late). Interstitial amphibole is enriched in Ba and LREE compared with early crystallised amphibole and does not follow typical fractionation trends. Modelling of melt compositions indicates that a water-rich, plagioclase-undersaturated reactive melt or fluid percolated through a crystal mush, accompanied by the breakdown of clinopyroxene, and the crystallisation of amphibole. Geothermobarometry estimates and comparisons with experimental studies imply the majority of xenoliths formed in the mid-crust. Martinique cumulate xenoliths are

  12. Indoor radon risk associated to post-tectonic biotite granites from Vila Pouca de Aguiar pluton, northern Portugal.

    Science.gov (United States)

    Martins, L M O; Gomes, M E P; Teixeira, R J S; Pereira, A J S C; Neves, L J P F

    2016-11-01

    At Vila Pouca de Aguiar area, northern Portugal, crops out a post-tectonic Variscan granite pluton, related with the Régua-Vila Real-Verín fault zone, comprising three types of biotite granites. Among these granites, PSG granite yield the highest average contents of U, probably due to its enrichment in accessory U-bearing minerals such as zircon. In the proximity of faults and joints, these granites are often affected by different degrees of hydrothermal alteration, forming reddish altered rocks, commonly known as "episyenites". These altered rocks are probably associated to the occurrence of hydrothermal processes, which led to uranium enrichment in the most advanced stages of episyenitization. In these granites, both average gamma absorbed dose rates in outdoor and indoor air are higher than those of the world average. Furthermore, even in the worst usage scenario, all these granites can be used as a building material, since their annual effective doses are similar to the limit defined by the European Commission. The geometric mean of radon activity of 91 dwellings located at the Vila Pouca de Aguiar pluton is 568Bqm(-3), exceeding that of other northern Portuguese granites. Measurements carried out during a winter season, indicate that 62.6% of the analysed dwellings yield higher indoor radon average values than the Portuguese legislation limit (400Bqm(-3)), and annual effective doses due higher than the world's average value (1.2mSvy(-1)). The interaction of geogenic, architectural and anthropogenic features is crucial to explain the variance in the geometric mean of radon activity of dwellings from Vila Pouca de Aguiar pluton, but the role of geologic faults is probably the most important decisive factor to increase the indoor radon concentration in dwellings. Hence, the development of awareness campaigns in order to inform population about the incurred radiological risks to radon exposure are highly recommended for this specific area.

  13. Internal fabrics in magmatic plutons emplaced in extended brittle crust - insight from analogue models with AMS (Anisotropy of Magnetic Susceptibility)

    Science.gov (United States)

    Mirzaei, Masoud; Zavada, Prokop; Machek, Matej; Roxerova, Zuzana

    2016-04-01

    Magma emplacement in extended brittle crust was simulated by injecting plaster of Paris (magma) into a large sandbox with central deformable rubber sheet. Analog magma is during the experiments injected through small circular inlet cut in the center of the elastic sheet. Injection force oscillation during the steadily evacuating analog magma was recorded during the experiments and regularly showed 3-4 increases followed by a quick drop. The recorded oscillation amplitude is largest for static injection without extension of the sandbox, which formed a columnar body with concentric and zonal internal fabric. Experiments including normal or oblique 20% extension resulted in along rift axis elongated oblate ellipsoidal pluton with rift parallel ridges in the top part of the pluton. Inspection of horizontal profiles show bone-shaped internal zoning patterns limited by conjugate sets of shear zones. Orientation of these internal shear zones is correlated with the sand-clock fault pattern developed in the overburden sand pack. Another set of shear zones parallel with the long axes of the plutons (rift axis) are associated with successive emplacement of distinct plaster pulses during the buildup of the entire body. The innermost lastly emplaced pulses of plaster display weak vertical magnetic fabrics with vertical lineations, while the outer shells of already emplaced plaster reveal stronger and margin parallel oblate magnetic fabrics with subhorizontal lineations. We interpret the vertical innermost fabrics as a result of active ascent of plaster from the injection inlet, while the fabrics in the outer zones likely reflect push due to inflation of the inner domain reflected in the reworking of the magnetic fabric.

  14. Crystallization conditions of porphyritic high-K calc-alkaline granitoids in the extreme northeastern Borborema Province, NE Brazil, and geodynamic implications

    Science.gov (United States)

    Campos, Benedita Cleide Souza; Vilalva, Frederico Castro Jobim; Nascimento, Marcos Antônio Leite do; Galindo, Antônio Carlos

    2016-10-01

    An integrated textural and chemical study on amphibole, biotite, plagioclase, titanite, epidote, and magnetite was conducted in order to estimate crystallization conditions, along with possible geodynamic implications, for six Ediacaran porphyritic high-K calc-alkaline granite plutons (Monte das Gameleiras, Barcelona, Acari, Caraúbas, Tourão, and Catolé do Rocha) intrusive into Archean to Paleoproterozoic rocks of the São José do Campestre (SJCD) and Rio Piranhas-Seridó (RPSD) domains, northern Borborema Province. The studied rocks include mainly porphyritic leucocratic monzogranites, as well as quartz-monzonites and granodiorites. Textures are marked by K-feldspar megacrysts (5-15 cm long) in a fine-to medium-grained matrix composed of quartz, plagioclase, amphibole, biotite, as well as titanite, epidote, Fesbnd Ti oxides, allanite, apatite, and zircon as accessory minerals. Amphibole, biotite and titanite share similar compositional variations defined by increasing Al and Fe, and decreasing Mg contents from the plutons emplaced into the SJCP (Monte das Gameleiras and Barcelona) towards those in the RPSD (Acari, Caraúbas, Tourão, and Catolé do Rocha). Estimated intensive crystallization parameters reveal a weak westward range of increasing depth of emplacement, pressure and temperature in the study area. The SJCD plutons (to the east) crystallized at shallower crustal depths (14-21 km), under slightly lower pressure (3.8-5.5 kbar) and temperature (701-718 °C) intervals, and high to moderate oxygen fugacity conditions (+0.8 plutons (to the west) were emplaced at slightly deeper depths (18-23 km), under higher, yet variable pressures (4.8-6.2 kbar), temperatures (723-776 °C), and moderate to low oxygen fugacity conditions (-1.0 < ΔFQM < +1.8). These results reinforce the contrasts between the tectono-strutuctural domains of São José do Campestre and Rio Piranhas-Seridó in the northern Borborema Province.

  15. Structural characterization of the Misajé granitic pluton (NW Cameroon): constraints from magnetic and field observations

    Science.gov (United States)

    Fozing, Eric Martial; Njanko, Théophile; Naba, Séta; Kwékam, Maurice; Njonfang, Emmanuel; Rochette, Pierre

    2016-11-01

    The Misajé granitic pluton, emplaced between 569 and 560 Ma in an amphibolitic and gneissic host rock, comprises four petrographic units namely biotite-hornblende granite (BHG), granodiorite (Gd), biotite granite (BG), and leucocratic granite (LG). Four major tectonic events have been described in the studied area: a D1-early tectonic event, responsible of the E-W flat foliation which has been progressively transposed by a D2 tectonic event. A D2 event has developed heterogeneous simple shear in a dextral transpressive context with moderate to strong dipping NE-SW striking foliation; a D3 tectonic event has lead to a sinistral N-S ductile shear characterized by N- to ENE-striking foliation and E-W strike-slip shear corridors and a D4 tectonic event that developed N-S dextral ductile strike-slip deformation. The magnetic study of the pluton, based on the AMS parameters, reveals the coexistence of both paramagnetic (dominated by iron-bearing silicates; 54 % of sites) and ferromagnetic (due to the occurrence of PSD and MD grains of magnetite or other ferromagnetic minerals; 46 % of sites) behaviors. Magnetic foliation shows best poles at 55/82 for the whole pluton, 95/32 in BHG, and 273/83 in BG, and the magnetic lineation trends are mostly NNE-SSW with best lines at 210/8, 198/19, and 36/3, respectively. The trend of the magnetic lineation in BG indicates an S-shape trajectory, suggesting a sinistral sense of shear motion along discrete E-W corridors situated at the northern and southern ends. Kinematic indicators in BG point to a sinistral sense of shear, suggesting its emplacement during the D3 event. The close relationship between K 1 and K 3 points to a syn-kinematic emplacement and crystallization of the Misajé granitic pluton during the Pan-African event, and the tectonic evolution of the study area is considered to be coeval with the tectonic evolution of the trans-Saharan Pan-African belt of eastern Nigeria.

  16. The alkaline diet: is there evidence that an alkaline pH diet benefits health?

    Science.gov (United States)

    Schwalfenberg, Gerry K

    2012-01-01

    This review looks at the role of an alkaline diet in health. Pubmed was searched looking for articles on pH, potential renal acid loads, bone health, muscle, growth hormone, back pain, vitamin D and chemotherapy. Many books written in the lay literature on the alkaline diet were also reviewed and evaluated in light of the published medical literature. There may be some value in considering an alkaline diet in reducing morbidity and mortality from chronic diseases and further studies are warranted in this area of medicine.

  17. The Alkaline Diet: Is There Evidence That an Alkaline pH Diet Benefits Health?

    Directory of Open Access Journals (Sweden)

    Gerry K. Schwalfenberg

    2012-01-01

    Full Text Available This review looks at the role of an alkaline diet in health. Pubmed was searched looking for articles on pH, potential renal acid loads, bone health, muscle, growth hormone, back pain, vitamin D and chemotherapy. Many books written in the lay literature on the alkaline diet were also reviewed and evaluated in light of the published medical literature. There may be some value in considering an alkaline diet in reducing morbidity and mortality from chronic diseases and further studies are warranted in this area of medicine.

  18. Chronological and geochemical studies of granite and enclave in Baimashan pluton, Hunan, South China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Zircon LA-ICP-MS U-Pb dating reveals that the Baimashan Pluton is composed mainly of late Indosinian (204.5±2.8 Ma-209.2±3.8 Ma) biotite granodiorites/monzonitic granites (LIGs) and early Yanshanian (176.7±1.7 Ma) two-micas monzonitic granites (EYGs),and the coeval (203.2±4.5 Ma-205.1±3.9 Ma) mafic microgranular enclaves (MMEs) are generally found in the former.In addition,the ages of cores within zircons from LIGs and MMEs ranging from 221.4±4.0 Ma to 226.5±4.1Ma provide evidence of multistage magma intrusion during Indosinian in the study area.Measured 3010±20.6 Ma of inherited zircon age suggests that there may be recycling Archaean curstal material in existence in this area.LIGs and EYGs share some similar geochemical features: subalkaline and peraluminous granites,enrichment of Th,U,K,Ta,Zr,Hf and LREE but depletion of Ba,Nb,P,Ti and Eu,low εNd(t) values but high (87Sr/86Sr)i ratios,and old T2DM (ca.1.9-2.0 Ga).The behaviors of incompatible elements and REE are mainly dominated by fractional crystallization of plagioclase,K-feldspar,ilmenite and apatite,but that of Sr isotope mainly controlled by EC-AFC.They are crust-sourced and derived from partial melting of paleo-Proterozoic metagreywackes and related to biotite dehydration melting.LIGs are formed in post-collisional tectonic setting as crustal local extension and thinning during late Indosinian.But EYGs may be evolved products of congeneric granitic magma with LIGs formed in late Indoinian,which were emplaced again when crust underwent extensive thinning and extension in post-orogenic tectonic setting during Yanshanian in SC after undergoing EC-AFC.MMEs should be cognate enclaves and derived from liquid immiscibility of host magma.

  19. Biomass production on saline-alkaline soils

    Energy Technology Data Exchange (ETDEWEB)

    Chaturvedi, A.N.

    1985-01-01

    In a trial of twelve tree species (both nitrogen fixing and non-fixing) for fuel plantations on saline-alkaline soil derived from Gangetic alluvium silty clay, Leucaena leucocephala failed completely after showing rapid growth for six months. Results for other species at age two showed that Prosopis juliflora had the best productivity.

  20. Use Alkalinity Monitoring to Optimize Bioreactor Performance.

    Science.gov (United States)

    Jones, Christopher S; Kult, Keegan J

    2016-05-01

    In recent years, the agricultural community has reduced flow of nitrogen from farmed landscapes to stream networks through the use of woodchip denitrification bioreactors. Although deployment of this practice is becoming more common to treat high-nitrate water from agricultural drainage pipes, information about bioreactor management strategies is sparse. This study focuses on the use of water monitoring, and especially the use of alkalinity monitoring, in five Iowa woodchip bioreactors to provide insights into and to help manage bioreactor chemistry in ways that will produce desirable outcomes. Results reported here for the five bioreactors show average annual nitrate load reductions between 50 and 80%, which is acceptable according to established practice standards. Alkalinity data, however, imply that nitrous oxide formation may have regularly occurred in at least three of the bioreactors that are considered to be closed systems. Nitrous oxide measurements of influent and effluent water provide evidence that alkalinity may be an important indicator of bioreactor performance. Bioreactor chemistry can be managed by manipulation of water throughput in ways that produce adequate nitrate removal while preventing undesirable side effects. We conclude that (i) water should be retained for longer periods of time in bioreactors where nitrous oxide formation is indicated, (ii) measuring only nitrate and sulfate concentrations is insufficient for proper bioreactor operation, and (iii) alkalinity monitoring should be implemented into protocols for bioreactor management.

  1. Alkaline electrochemical cells and method of making

    Science.gov (United States)

    Hoyt, H. E.; Pfluger, H. L. (Inventor)

    1970-01-01

    Equilibrated cellulose ether membranes of increased electrolytic conductivity for use as separators in concentrated alkaline electrochemical cells are investigated. The method of making such membranes by equilibration to the degree desired in an aqueous alkali solution mantained at a temperature below about 10 C is described.

  2. Petrography and mineral chemistry of the composite Deboullie Pluton, northern Maine, USA: implications for the genesis of Cu-Mo mineralization

    Science.gov (United States)

    Loferski, P.J.; Ayuso, R.A.

    1995-01-01

    Biotite and apatite mineral chemistry, particularly halogen abundances and ratios, are used to investigate the relation of the two contrasting parts of the Deboullie composite pluton (syenite-granodiorite) located in northern Maine. Biotite mineral chemistry helps to classify the weakly developed porphyry-style mineralization (Cu-Mo) associated with syenitic rocks of the Deboullie pluton. Biotite and apatite occur within the matrix of the rocks and within small multiphase inclusions hosted by clinopyroxene. The inclusions are interpreted to be crystallized melt inclusions rather than solid inclusions, that were trapped by clinopyroxene during growth. The multiphase inclusions consist of K-feldspar + quartz + biotite + apatite + magnetite. On a regional scale, biotite compositions from granitic plutons in Maine do not vary in a systematic manner. -from Authors

  3. Koncentracije lebdećih čestica PM1, PM2.5, PM10 u zatvorenom prostoru te koncentracije PM2,5 čestica u otvorenom prostoru osnovnih škola u gradu Sariju u Iranu

    OpenAIRE

    2013-01-01

    Svrha je ovog istraživanja bila utvrditi raspodjelu lebdećih čestica u osnovnim školama u središtu iranskoga grada Sarija te vidjeti jesu li razine lebdećih čestica mjerenih u dvorištima škola i u učionicama međusobno povezane. Vani su mjerene PM2,5 čestice pomoću stalnog Micro Dust Pro monitora, a unutra PM1, PM2,5 i PM10 čestice pomoću GRIMM monitora. Oba su instrumenta kalibrirana gravimetrijskom metodom pomoću filtara. Kolmogorov-Smirnovljev test pokazao je normalnu raspodjelu vanjskih mj...

  4. Titanium corrosion in alkaline hydrogen peroxide environments

    Science.gov (United States)

    Been, Jantje

    1998-12-01

    The corrosion of Grade 2 titanium in alkaline hydrogen peroxide environments has been studied by weight loss corrosion tests, electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) measurements and potentiodynamic polarography. Calcium ions and wood pulp were investigated as corrosion inhibitors. In alkaline peroxide, the titanium corrosion rate increased with increasing pH, temperature, and hydrogen peroxide concentration. The corrosion controlling mechanism is thought to be the reaction of the oxide with the perhydroxyl ion. No evidence of thermodynamically stable calcium titanate was found in the surface film of test coupons exposed to calcium-inhibited alkaline peroxide solutions. Calcium inhibition is probably the result of low local alkali and peroxide concentrations at the metal surface produced by reaction of adsorbed calcium with hydrogen peroxide. It has been shown that the inhibiting effect of calcium is temporary, possibly through an effect of calcium on the chemical and/or physical stability of the surface oxide. Pulp is an effective and stable corrosion inhibitor. Raising the pulp concentration decreased the corrosion rate. The inhibiting effect of pulp may be related to the adsorption and interaction of the pulp fibers with H 2O2, thereby decreasing the peroxide concentration and rendering the solution less corrosive. The presence of both pulp and calcium led to higher corrosion rates than obtained by either one inhibitor alone. Replacement of hydrofluoric acid with alkaline peroxide for pickling of titanium was investigated. Titanium corrosion rates in alkaline peroxide exceeded those obtained in the conventional hydrofluoric acid bath. General corrosion was observed with extensive roughening of the surface giving a dull gray appearance. Preferred dissolution of certain crystallographic planes was investigated through the corrosion of a titanium single crystal. Whereas the overall effect on the corrosion rate was small

  5. Metamorphic evolution of the contact aureole of the Jhirgadandi pluton, Sonbhadra district,Mahakoshal mobile belt, central India

    Indian Academy of Sciences (India)

    S P Singh; Anand K Srivastava; Gopendra Kumar; S B Dwivedi

    2013-06-01

    The metamorphic evolution of the contact aureole around the Late Paleoproterozoic Jhirgadandi pluton in the eastern part of Parsoi Formation of Mahakoshal terrain, central India represents three distinct metamorphic zones, characterized by definite mineral assemblages. The contact-metamorphic event produced the peak-metamorphic mineral assemblages Bt + Qtz + Alb + Sil ± Cd ± Grt ± Mus ± Kfs in the metapelites of inner aureole, Bt + Qtz + And + Mus + Kfs + Plag ± Cd ± Chl in middle aureole and Chl + Mus + Bt ± And + Alb + Qtz ± Ep + Mt ± tourmaline in the outer aureole. The estimated P–T conditions based on detailed geothermobarometric calculations in the thermal metamorphosed rocks are 690°C/3.4 kbar, 580 ± 15°C and 487 ± 30°C in inner aureole, middle aureole and outer aureole, respectively. The variation in metamorphic condition suggests that the shallow crustal level emplacement of Jhirgadandi pluton is responsible for the overprinting of contact metamorphic assemblages (M2) in the low grade metapelites (regional metamorphism M1) of Mahakoshal Group.

  6. Geochemistry and petrogenesis of anorogenic basic volcanic-plutonic rocks of the Kundal area, Malani Igneous Suite, western Rajasthan, India

    Science.gov (United States)

    Krishnakanta Singh, A.; Vallinayagam, G.

    2004-12-01

    The Kundal area of Malani Igneous Suite consists of volcano-plutonic rocks. Basalt flows and gabbro intrusives are associated with rhyolite. Both the basic rocks consist of similar mineralogy of plagioclase, clinopyroxene as essential and Fe-Ti oxides as accessories. Basalt displays sub-ophitic and glomeroporphyritic textures whereas gabbro exhibits sub-ophitic, porphyritic and intergrannular textures. They show comparable chemistry and are enriched in Fe, Ti and incompatible elements as compared to MORB/CFB. Samples are enriched in LREE and slightly depleted HREE patterns with least significant positive Eu anomalies. Petrographical study and petrogenetic modeling of [Mg]-[Fe], trace and REE suggest cogenetic origin of these basic rocks and they probably derived from Fe-enriched source with higher Fe/Mg ratio than primitive mantle source. Thus, it is concluded that the basic volcano-plutonic rocks of Kundal area are the result of a low to moderate degree (conformity with the similar setting for Malani Igneous Suite.

  7. Paleozoic subduction complex and Paleozoic-Mesozoic island-arc volcano-plutonic assemblages in the northern Sierra terrane

    Science.gov (United States)

    Hanson, Richard E.; Girty, Gary H.; Harwood, David S.; Schweickert, Richard A.

    2000-01-01

    This field trip provides an overview of the stratigraphic and structural evolution of the northern Sierra terrane, which forms a significant part of the wall rocks on the western side of the later Mesozoic Sierra Nevada batholith in California. The terrane consists of a pre-Late Devonian subduction complex (Shoo Fly Complex) overlain by submarine arc-related deposits that record the evolution of three separate island-arc systems in the Late Sevonian-Early Mississippian, Permian, and Late Triassic-Jurassic. The two Paleozoic are packages and the underlying Shoo Fly Complex have an important bearing on plate-tectonic processes affecting the convergent margin outboard of the Paleozoic Cordilleran miogeocline, although their original paleogeographic relations to North America are controversial. The third arc package represents an overlap assemblage that ties the terrane to North America by the Late Triassic and helps constrain the nature and timing of Mesozoic orogenesis. Several of the field-trip stops examine the record of pre-Late Devonian subduction contained in the Shoo Fly Complex, as well as the paleovolcanology of the overlying Devonian to Jurassic arc rocks. Excellent glaciated exposures provide the opportunity to study a cross section through a tilted Devonian volcano-plutonic association. Additional stops focus on plutonic rocks emplaced during the Middle Jurassic arc magmatism in the terrane, and during the main pulse of Cretaceous magmatism in the Sierra Nevada batholith to the east.

  8. Geochemistry and petrogenesis of anorogenic basic volcanic-plutonic rocks of the Kundal area, Malani Igneous Suite, western Rajasthan, India

    Indian Academy of Sciences (India)

    A Krishnakanta Singh; G Vallinayagam

    2004-12-01

    The Kundal area of Malani Igneous Suite consists of volcano-plutonic rocks. Basalt flows and gabbro intrusives are associated with rhyolite. Both the basic rocks consist of similar mineralogy of plagioclase, clinopyroxene as essential and Fe-Ti oxides as accessories. Basalt displays sub-ophitic and glomeroporphyritic textures whereas gabbro exhibits sub-ophitic, porphyritic and intergrannu- lar textures. They show comparable chemistry and are enriched in Fe, Ti and incompatible ele- ments as compared to MORB/CFB. Samples are enriched in LREE and slightly depleted HREE patterns with least significant positive Eu anomalies. Petrographical study and petrogenetic mod- eling of [Mg]-[Fe], trace and REE suggest cogenetic origin of these basic rocks and they probably derived from Fe-enriched source with higher Fe/Mg ratio than primitive mantle source. Thus, it is concluded that the basic volcano-plutonic rocks of Kundal area are the result of a low to moderate degree (> 30%) partial melting of source similar to picrite/komatiitic composition. Within plate, anorogenic setting for the basic rocks of Kundal area is suggested, which is in conformity with the similar setting for Malani Igneous Suite.

  9. Brasiliano-age granitoids in the Sergipana Fold Belt, NE Brazil: the Coronel João Sá Pluton

    Science.gov (United States)

    Mcreath, I.; Lafon, J. M.; Davison, I.; Chaves, J. M.; Conceiçāo, H.

    1998-01-01

    The Coronel João Sá pluton is a zoned Brasiliano-age, late- to post-tectonic intrusion in the Macururé schist domain of the Sergipana Foldbelt, Northeast Brazil. Biotite-hornblende granodiorite predominates, and flattened ultramafic to intermediate enclaves are present. Igneous orientations are present but fabrics produced by strong solid-state flattening are absent. Rb-Sr whole rock isochrons including enclaves and their host rocks yielded a probable intrusion age of 614 Ma which dates the waning phase of the dominant deformation which produced the F2 foliation of the Sergipana belt and is close to ages reported for late tectonic granites in other Brasiliano domains of Northeast Brazil. More radiogenic Sr (I Sr(614) = 0.71008 ± 52) is present in some felsic rocks, while less radiogenic Sr (I Sr(614) = 0.70814 ± 18) is mainly found in the more mafic core of the main body. Sr isotopic equilibrium between most enclaves and their host rocks was attained. Textural evidence, especially in the enclaves, shows that magma mixing occurred, but late biotite formation in the enclaves caused modifications of their chemical compositions. The geological, petrographical and isotopic evidence shows that the pluton was probably fed by a complex feeder system into the crust under extensional conditions. Variable upper crustal contamination was probably responsible for the isotopic heterogeneity of Sr.

  10. The link between volcanism and plutonism in epizonal magma systems; high-precision U-Pb zircon geochronology from the Organ Mountains caldera and batholith, New Mexico

    Science.gov (United States)

    Rioux, Matthew; Farmer, G. Lang; Bowring, Samuel A.; Wooton, Kathleen M.; Amato, Jeffrey M.; Coleman, Drew S.; Verplanck, Philip L.

    2016-02-01

    The Organ Mountains caldera and batholith expose the volcanic and epizonal plutonic record of an Eocene caldera complex. The caldera and batholith are well exposed, and extensive previous mapping and geochemical analyses have suggested a clear link between the volcanic and plutonic sections, making this an ideal location to study magmatic processes associated with caldera volcanism. Here we present high-precision thermal ionization mass spectrometry U-Pb zircon dates from throughout the caldera and batholith, and use these dates to test and improve existing petrogenetic models. The new dates indicate that Eocene volcanic and plutonic rocks in the Organ Mountains formed from ~44 to 34 Ma. The three largest caldera-related tuff units yielded weighted mean 206Pb/238U dates of 36.441 ± 0.020 Ma (Cueva Tuff), 36.259 ± 0.016 Ma (Achenback Park tuff), and 36.215 ± 0.016 Ma (Squaw Mountain tuff). An alkali feldspar granite, which is chemically similar to the erupted tuffs, yielded a synchronous weighted mean 206Pb/238U date of 36.259 ± 0.021 Ma. Weighted mean 206Pb/238U dates from the larger volume syenitic phase of the underlying Organ Needle pluton range from 36.130 ± 0.031 to 36.071 ± 0.012 Ma, and the youngest sample is 144 ± 20 to 188 ± 20 ka younger than the Squaw Mountain and Achenback Park tuffs, respectively. Younger plutonism in the batholith continued through at least 34.051 ± 0.029 Ma. We propose that the Achenback Park tuff, Squaw Mountain tuff, alkali feldspar granite and Organ Needle pluton formed from a single, long-lived magma chamber/mush zone. Early silicic magmas generated by partial melting of the lower crust rose to form an epizonal magma chamber. Underplating of the resulting mush zone led to partial melting and generation of a high-silica alkali feldspar granite cap, which erupted to form the tuffs. The deeper parts of the chamber underwent continued recharge and crystallization for 144 ± 20 ka after the final eruption. Calculated magmatic

  11. Characteristic Features and U—Pb Isotopic Ages of Zircons in a Middle Proterozoic Granite Pluton from Baohan Area,Hainan Province,China

    Institute of Scientific and Technical Information of China (English)

    邓铁殷; 陈毓蔚; 等

    1993-01-01

    The crystal form,chemical composition and U-Pb isotopic composition of various zircon fractions is a Middle Proterozoic granite pluton from the Baoban area suggest that the zircons are typically magmatogenic in nature,and different from those of sedimentary and epigenetic orgins.The various zircon fractions yielded and age of about 1440.87Ma,which may represent the ge of zircon crystallization.The so-called aoban-group migmatite is,as a matter of fact,a Middle Proterozoic granite pluton.

  12. Improved electrodes and gas impurity investigations on alkaline electrolysers

    DEFF Research Database (Denmark)

    Reissner, R.; Schiller, G.; Knoeri, T.;

    Alkaline water electrolysis for hydrogenproduction is a well-established techniquebut some technological issues regarding thecoupling of alkaline water electrolysis andRenewable Energy Sources (RES) remain tobe improved....

  13. [Leucocyte alkaline phosphatase in normal and pathological pregnancy (author's transl)].

    Science.gov (United States)

    Stark, K H; Zaki, I; Sobolewski, K

    1981-01-01

    The activities of leucocyte alkaline phosphatase were determined in 511 patients with normal and pathological pregnancy. Mean values were compared and the enzyme followed up, and the conclusion was drawn that leucocyte alkaline phosphatase was no safe indicator of foetal condition. No direct relationship were found to exist between leucocyte alkaline phosphatase, total oestrogens, HSAP, HLAP, HPL, and oxytocinase.

  14. Petrochemistry and mineralogy of Dongyuan tungsten-bearing pluton in eastern Jiangnan Orogen%江南造山带东段东源含钨岩体的岩石化学、矿物学特征研究

    Institute of Scientific and Technical Information of China (English)

    周洁; 葛伟亚; 姜耀辉; 徐生发; 傅建真

    2015-01-01

    Dongyuan pluton, geographically located in south Anhui Province, is a part of eastern Jiangnan orogen. It is composed of granodiorite, monzogranite, syenogranite, showing obvious formation of sericite and carbonate in feldspar, and formation of muscovite and chlorite in biotite. Zircon LA-ICP-MS U-Pb dating results show that the pluton was emplaced at 146.7 Ma. In addition, abundant inherited zircons are identified in the granite, showing the average age of the Neoproterozoic zircon is (770.2±9.7) Ma. Biotite in Dongyuan pluton can be classified as high-Mg type, and is plotted in the crust-mantle zone on the material source discrimination diagram. The Dongyuan pluton belongs to the high potassium calc alkaline and shoshonitic series, being metaluminous-peraluminous, showing relatively high Sr and Ba, low Y and Yb, and weak negative Eu anomalies (δEu =0.74~0.83). It is enriched in light rare earth elements (LREE) and light ion lithophile elements (LILE) but is depleted in high field strength elements (HFSE), exhibiting strongly fractionated REE pattern. The pluton exhibits high initial 87Sr/86Sr ratios (0.7124), low εNd(t) (–5.53), and variable zircon εHf(t) (–13.0~ –7.0) values. The elemental and isotopic data suggests that the Dongyuan granite shows some affinities with adakite, so can be postulated to be most likely derived from partial melting of thickened lower crust with little contribution from mantle components.%东源岩体主要由花岗闪长岩、二长花岗岩、正长花岗岩构成。长石绢云母化、碳酸盐化作用较强,黑云母发生白云母化和轻微绿泥石化蚀变。锆石LA-ICP-MS U-Pb定年获得岩体的成岩年龄为晚侏罗世-早白垩世((146.7±4.1) Ma);含有大量新元古代的继承锆石,加权平均年龄为(770.2±9.7) Ma。岩体中黑云母为镁质黑云母,显示寄主岩为壳幔混合来源。岩石地球化学特征总体表现为高钾钙碱性系列-橄榄粗玄岩系列,准铝质-过铝质,

  15. A Fresh Plutonic Igneous Angrite Containing Grain Boundary Glass From Tamassint, Northwest Africa

    Science.gov (United States)

    Irving, A. J.; Kuehner, S. M.; Rumble, D.

    2006-12-01

    Tamassint Angrite: A small fragmented stone found in June 2006 south of Tamassint oasis in the Morocco-Algeria border region represents a new type of angrite lithology, unlike the coarse grained metamorphic or fine grained "basaltic" to quench-textured examples known previously. This extremely fresh, fusion-crusted specimen has a coarse grained (0.6-12 mm) plutonic igneous cumulate texture, and is composed of Al-Ti-rich clinopyroxene (33.4%), pure anorthite (28.6%), Ca-rich olivine (18.7%) with prominent exsolution lamellae (10-50 μm wide) of kirschsteinite, ulvöspinel (18.5%), and accessory glass, troilite and metal. Subhedral anorthite grains are partially enclosed within larger ulvöspinel grains. Mineral compositions are as follows: clinopyroxene (Fs20.8-33.3Wo53-54.9, Al2O3 = 5.7 to 9.4 wt.%, TiO2 = 0.9 to 2.9 wt.%, FeO/MnO = 85-278), olivine (Fa72.6-74.7Ln3.5-3.6, CaO = 2.1 wt.%, FeO/MnO = 70-87), kirschsteinite (Fa44.7-45.4Ln46-47.2, FeO/MnO = 73-82), ulvöspinel (TiO2 = 27.6 wt.%, Al2O3 = 5.5 wt.%). Reintegration of the kirschsteinite lamellae gives a pre-exsolution olivine composition of Fa68.1Ln12.2 with 7.3 wt.% CaO. Present along grain boundaries (notably between anorthite and ulvöspinel) are narrow (5-20 μm) curvilinear zones of glass associated with secondary kirschteinite, clinopyroxene and olivine (which show similar curvilinear morphology and truncate kirschsteinite lamellae). Glass compositions plot close to a mixing line between anorthite and ulvöspinel. Replicate oxygen isotopic analyses of acid-washed minerals by laser fluorination gave δ18O = 3.881, 3.845, δ17O = 1.967, 1.927, Δ17O = -0.0745, -0.0956 per mil (for TFL slope = 0.526). Comparison With NWA 2999: We previously showed [1] that angrite Northwest Africa 2999 is a metamorphically annealed breccia with distinctive symplectites and coronas representing forward and reverse versions of the same solid state reaction. We suggested that these disequilibrium textures required burial

  16. Oxidation catalysts on alkaline earth supports

    Energy Technology Data Exchange (ETDEWEB)

    Mohajeri, Nahid

    2017-03-21

    An oxidation catalyst includes a support including particles of an alkaline earth salt, and first particles including a palladium compound on the support. The oxidation catalyst can also include precious metal group (PMG) metal particles in addition to the first particles intermixed together on the support. A gas permeable polymer that provides a continuous phase can completely encapsulate the particles and the support. The oxidation catalyst may be used as a gas sensor, where the first particles are chemochromic particles.

  17. Mineral Chemistry and Crystallization Conditions of the Late Cretaceous Mamba Pluton from the Eastern Gangdese, Southern Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    Xiaowei Li; Xuanxue Mo; Mark Scheltens; Qi Guan

    2016-01-01

    The Late Cretaceous Mamba granodiorite belongs to a part of the Mesozoic Gangdese con-tinental magmatic belt. No quantitative mineralogical study has been made hitherto, and hence the depth at which it formed is poorly constrained. Here we present mineralogical data for the Mamba pluton, in-cluding host rocks and their mafic microgranular enclaves (MMEs), to provide insights into their overall crystallization conditions and information about magma mixing. All amphiboles in the Mamba pluton are calcic, withB(Ca+Na)>1.5, and Si=6.81–7.42 apfu for the host rocks and Si=6.77–7.35 apfu for the MMEs. The paramount cation substitutions in amphibole include edenite type and tschermakite type. Biotites both in the host rocks and the MMEs collectively have high MgO (13.19 wt.%–13.03 wt.%) contents, but define a narrow range of Al apfu (atoms per formula unit) variations (2.44–2.57). The oxygen fugacity es-timates are based on the biotite compositions cluster around the NNO buffer. The calculated pressure ranges from 1.2 to 2.1 kbar according to the aluminum-in-hornblende barometer. The computed pressure varies from 0.9 to 1.3 kbar based on the aluminum-in-biotite barometer which corresponds to an average depth of ca. 3.9 km. Besides, the estimates of crystallization pressures vary from 0.8 to 1.4 kbar based on the amphibole barometer proposed by Ridolfi et al. (2010), which can be equivalent to the depths ranging from 3.1 to 5.2 km. The MMEs have plagioclase oscillatory zonings and quartz aggregates, probably indi-cating the presence of magma mixing. Besides, core-to-rim element variations (Rb, Sr, Ba, and P) for the K-feldspar megacrysts serve as robust evidence to support magma mixing and crystal fractionation. This indicates the significance of the magma mixing that contributes to the formation of K-feldspar megacryst zonings in the Mamba pluton.

  18. Strain Localization Within a Syn-Tectonic Pluton in a Back-Arc Extensional Context: the Naxos granodiorite (Cyclades, Greece)

    Science.gov (United States)

    Bessiere, Eloïse; Rabillard, Aurélien; Arbaret, Laurent; Jolivet, Laurent; Augier, Romain; Menant, Armel

    2016-04-01

    Naxos Island is part of the central Cyclades (Aegean Sea, Greece) where a series of migmatite-cored metamorphic domes were exhumed below large-scale detachment systems during a Cenozoic back-arc extension. On Naxos, the Miocene exhumation history of the high-temperature metamorphic dome was notably achieved through two anastomosing and closely spaced top-to-the-north detachments belonging to the Naxos-Paros detachment system. According to previous contributions, the late exhumation stages were accompanied by the emplacement of a syn-kinematic I-type granodiorite that intruded a ductile-then-brittle detachment. Later the detachment migrated at the interface between the pluton and the metamorphic unit under ductile-to-brittle conditions. To clarify how extensional deformation was precisely distributed within the pluton, a multi-scale approach from field observations to laboratory investigations was undertaken. Through macro- to micro-structural observations, we show a continuous deformation history from magmatic to solid-state ductile/brittle conditions under an overall north-directed shearing deformation. The early magmatic or sub-solidus deformation is evidenced in a large part of the granodiorite, notably in its southern part where the original intrusive contact is still preserved. Solid-state deformation is recorded further north when approaching the detachment zone, highlighted by a thicker cataclastic zone and numerous pseudotachylite veins. From these field observations, we defined six strain facies, leading us to propose a qualitative strain map of the Naxos granodiorite. Based on field pictures and X-ray tomography of oriented samples collected along the strain gradient, we quantified the intensity of mineralogical fabrics in 2D and 3D. This step required the treatment of 600 rocks samples and pictures using SPO2003 (Shape Preferred Orientation) and Intercepts2003. Measured shape variations of the strain ellipsoid thus corroborate the large-scale strain

  19. Time-scales of assembly and thermal history of a composite felsic pluton: constraints from the Emerald Lake area, northern Canadian Cordillera, Yukon

    Science.gov (United States)

    Coulson, Ian M.; Villeneuve, Mike E.; Dipple, Gregory M.; Duncan, Robert A.; Russell, James K.; Mortensen, James K.

    2002-05-01

    Knowledge of the time-scales of emplacement and thermal history during assembly of composite felsic plutons in the shallow crust are critical to deciphering the processes of crustal growth and magma chamber development. Detailed petrological and chemical study of the mid-Cretaceous, composite Emerald Lake pluton, from the northern Canadian Cordillera, Yukon Territory, coupled with U-Pb and 40Ar/ 39Ar geochronology, indicates that this pluton was intruded as a series of magmatic pulses. Intrusion of these pulses produced a strong petrological zonation from augite syenite, hornblende quartz syenite and monzonite, to biotite granite. Our data further indicate that multiple phases were emplaced and cooled to below the mineral closure temperatures over a time-scale on the order of the resolution of the 40Ar/ 39Ar technique (˜1 Myr), and that emplacement occurred at 94.3 Ma. Simple thermal modelling and heat conduction calculations were used to further constrain the temporal relationships within the intrusion. These calculations are consistent with the geochronology and show that emplacement and cooling were complete in less than 100 kyr and probably 70±5 kyr. These results demonstrate that production, transport and emplacement of the different phases of the Emerald Lake pluton occurred essentially simultaneously, and that these processes must also have been closely related in time and space. By analogy, these results provide insights into the assembly and petrogenesis of other complex intrusions and ultimately lead to an understanding of the processes involved in crustal development.

  20. Alkaline and ultrasound assisted alkaline pretreatment for intensification of delignification process from sustainable raw-material.

    Science.gov (United States)

    Subhedar, Preeti B; Gogate, Parag R

    2014-01-01

    Alkaline and ultrasound-assisted alkaline pretreatment under mild operating conditions have been investigated for intensification of delignification. The effect of NaOH concentration, biomass loading, temperature, ultrasonic power and duty cycle on the delignification has been studied. Most favorable conditions for only alkaline pretreatment were alkali concentration of 1.75 N, solid loading of 0.8% (w/v), temperature of 353 K and pretreatment time of 6 h and under these conditions, 40.2% delignification was obtained. In case of ultrasound-assisted alkaline approach, most favorable conditions obtained were alkali concentration of 1N, paper loading of 0.5% (w/v), sonication power of 100 W, duty cycle of 80% and pretreatment time of 70 min and the delignification obtained in ultrasound-assisted alkaline approach under these conditions was 80%. The material samples were characterized by FTIR, SEM, XRD and TGA technique. The lignin was recovered from solution by precipitation method and was characterized by FTIR, GPC and TGA technique.

  1. La Escalerilla pluton, San Luis Argentina: The orogenic and post-orogenic magmatic evolution of the famatinian cycle at Sierras de San Luis

    Science.gov (United States)

    Morosini, Augusto Francisco; Ortiz Suárez, Ariel Emilio; Otamendi, Juan Enrique; Pagano, Diego Sebastián; Ramos, Gabriel Alejandro

    2017-01-01

    Field relationships, geochemical analysis and two new absolute ages (LA-MC-ICP-MS U/Pb-zircon) allow the division of the La Escalerilla pluton (previously considered to be a single granitic body) into two different plutons: a new La Escalerilla pluton (s.s.), dated at 476.7 ± 9.6 Ma, that represents the northern portion, and the El Volcán pluton, dated at 404.5 ± 8.5 Ma, located in the southern sector. The La Escalerilla pluton is composed of three facies: (1) biotite-bearing granodiorite, (2) porphyritic biotite-bearing granite, and (3) porphyritic two micas-bearing leucogranite, being the presence of late-magmatic dykes in these facies common. The El Volcán pluton is composed of two main facies: 1) porphyritic biotite-bearing granite, and 2) two micas-bearing leucogranite, but amphibole-bearing monzodioritic and tonalititic mega-enclaves are also common, as well as some dykes of amphibole and clinopyroxene-bearing syenites. A peculiarity between the two plutons is that their most representative facies (porphyritic biotite-bearing granites) have, apart from different absolute ages, distinctive geochemical characteristics in their concentrations of trace elements; the La Escalerilla granite is comparatively poorer in Ba, Sr, Nb, La, Ce, P, and richer in Rb, Tb, Y, Tm and Yb. The El Volcán granite is notably enriched in Sr and depleted in Y, resulting in high Sr/Y ratios (12.67-39.08) compared to the La Escalerilla granite (1.11-2.41). These contrasts indicate that the separation from their sources occurred at different depths: below 25 km for the La Escalerilla, and above 30 km for the El Volcán. Moreover, the contrasts allow us to interpret a thin crust linked to an environment of pre-collisional subduction for the first case, and a thickened crust of post-collisional environment for the second, respectively.

  2. Ion Microprobe U-Th Ages of Zircon From Plutonic Rock Fragments Ejected by Mount Veniaminof Volcano, Alaska Peninsula

    Science.gov (United States)

    Bacon, C. R.; Sisson, T. W.; Mazdab, F. K.

    2006-05-01

    Mount Veniaminof volcano in the Aleutian arc provides an unusual opportunity to directly relate volcanic rocks to a coeval shallow pluton. Fragments of medium- to coarse-grained plutonic rock were ejected during Veniaminof's 3700 14C yr B.P. caldera-forming eruption. The gabbro, diorite, and miarolitic granodiorite fragments are direct evidence of assembly of a shallow pluton consisting of cumulate mush and vapor- saturated residual melt segregations. We used the USGS-Stanford SHRIMP RG (Sensitive High-Resolution Ion MicroProbe with Reverse Geometry) to analyze ~30-μm-diameter areas a few μm deep on individual polished 40-150 μm zircons separated from these plutonic rocks. Samples were sputtered with a 16-22 nA primary beam of 16O- ions and secondary ion intensities were measured for 90Zr216O, 180Hf16O, 238U, 230Th16O, background, 232Th16O, and 238U16O. Crystallization ages for the single zircon populations in each rock were determined by fitting isochrons to SHRIMP RG data plotted on (230Th/232Th) versus (238U/232Th) activity ratio diagrams, after rejecting analyses affected by contamination from the epoxy mounting medium (combination of 232Th and epoxy constituents that overlaps 230Th16O). The SHRIMP RG analyses define 238U-230Th isochron ages of 17.5 ± 1.8 ka and 11.7 +4.7/-4.5 ka for zircon crystallization in granodiorite and diorite, respectively (±2σ). Sparse zircons from two gabbro samples give 238U-230Th model ages of 36.6 +7.1/-6.7 ka and 26.4 +6.7/-6.4 ka using initial activity ratios defined by the granodiorite and diorite isochrons. Zircons from granodiorite and diorite, commonly bearing ~0.2-5 μm fluid inclusions, have exceptionally high U and Th contents (up to 2 and 5 wt.%, respectively) that may be explained by crystallization in the presence of late-magmatic aqueous fluid during passive degassing in the shallow subsurface. Veniaminof erupted medium- K basaltic through dacitic magmas over the past ~250 kyr that define an arc tholeiitic trend

  3. Zircon U-Pb geochronology, Sr-Nd-Hf isotopic composition and geological significance of the Late Triassic Baijiazhuang and Lvjing granitic plutons in West Qinling Orogen

    Science.gov (United States)

    Duan, Meng; Niu, Yaoling; Kong, Juanjuan; Sun, Pu; Hu, Yan; Zhang, Yu; Chen, Shuo; Li, Jiyong

    2016-09-01

    The Qinling Orogen was a consequence of continental collision of the South China Craton with the North China Craton in the Triassic and caused widespread granitoid magmatism. However, the petrogenesis of these granitoids remains controversial. In this paper, we choose the Baijiazhuang (BJZ) and Lvjing (LJ) plutons in the West Qinling Orogen for a combined study of the zircon U-Pb geochronology, whole-rock major and trace element compositions and Sr-Nd-Hf isotopic characteristics. We obtained zircon crystallization ages of 216 Ma and 212 Ma for the BJZ and the LJ plutons, respectively. The granitoid samples from both plutons have high K2O metaluminous to peraluminous compositions. They are enriched in large ion lithophile elements (LILEs), light rare earth elements (LREEs) and depleted in high field-strength elements (HFSEs) with significant negative Eu anomalies. The BJZ samples have initial Sr isotopic ratios of 0.7032 to 0.7078, εNd(t) of - 10.99 to - 8.54 and εHf (t) of - 10.22 to - 6.41. The LJ granitoids have initial Sr isotopic ratios of 0.7070 to 0.7080, εNd(t) of - 5.37 to - 4.58 and εHf(t) of - 3.64 to - 1.78. The enriched isotopic characteristics of the two plutons are consistent with their source being dominated by ancient continental crust. However, two BJZ samples show depleted Sr isotope compositions, which may infer possible involvement of mantle materials. Mantle-derived melt, which formed from partial melting of mantle wedge peridotite facilitated by dehydration of the subducted/subducting Mianlue ocean crust, provide the required heat for the crustal melting while also contributing to the compositions of these granitoids. That is, the two granitic plutons are magmatic responses to the closure of the Mianlue ocean basin and the continental collision between the Yangtze and South Qinling crustal terranes.

  4. Magmatic and solid state structures of the Abu Ziran pluton: Deciphering transition from thrusting to extension in the Eastern Desert of Egypt

    Science.gov (United States)

    Fritz, Harald; Loizenbauer, Jürgen; Wallbrecher, Eckart

    2014-11-01

    The 606 Ma old Abu Ziran granite of the Eastern Desert of Egypt intruded the southern margin of the Meatiq dome in a sinistral shear extensional setting. Its emplacement was enabled by a system of NW-trending sinistral shears, related Riedel shears and N-S extensional shear zones and faults. Magmatic flow was east-directed and controlled by Riedel shears that progressively rotated to an orientation favourable for extension. Strain markers that document magmatic flow show eastward decreasing strain together with strain increase from pluton centre to margins. This is explained by Newtonian flow between non-parallel plates and differences in flow velocities across the pluton. Solid state fabrics including shear fabrics, orientation of late magmatic dykes and quartz tension gashes, together with quartz C-axes distributions, document southward extensional shear within the solidified pluton and adjacent host rocks. Extensional shear is correlated with exhumation of the Meatiq dome coeval and soon after pluton solidification (585 Ma). Pressure temperature evolutionary paths, derived from fluid inclusions, show a clockwise path with exhumation by isothermal decompression in the Meatiq dome. By contrast, the overlying volcanosedimentary nappes experienced an anti-clockwise path released by temperature rise due to pluton emplacement followed by isobaric cooling. Quartz fabrics indicate high-temperature coaxial N-S flow in the northern Meatiq dome and lower-temperature, non-coaxial southward flow within the overlaying superficial nappe. This is explained by the exhumation process itself that progressively localised into simple shear domains when rocks approached higher crustal levels. Late extension at ca. 580 Ma was pure shear dominated and resulted in reversal of shear, now dextral, in the western Meatiq shear zone.

  5. Surfactant-enhanced alkaline flooding: Buffering at intermediate alkaline pH

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, J.; Wasan, D.T. (Illinois Inst. of Tech., Chicago, IL (United States))

    1993-11-01

    The alkaline flooding process involves injecting alkaline agents into the reservoir to produce more oil than is produced through conventional waterflooding. The interaction of the alkali in the flood water with the naturally occurring acids in the reservoir oil results in in-situ formation of soaps, which are partially responsible for lowering IFT and improving oil recovery. The extent to which IFT is lowered depends on the specific oil and injection water properties. Numerous investigators have attempted to clarify the relationship between system chemical composition and IFT. An experimental investigation of buffered alkaline flooding system chemistry was undertaken to determine the influence of various species present on interfacial tension (IFT) as a function of pH and ionic strength. IFT was found to go through an ultralow minimum in certain pH ranges. This synergism results from simultaneous adsorption of un-ionized and ionized acid species on the interface.

  6. Tyramine functions as a toxin in honey bee larvae during Varroa-transmitted infection by Melissococcus pluton.

    Science.gov (United States)

    Kanbar, G; Engels, W; Nicholson, G J; Hertle, R; Winkelmann, G

    2004-05-01

    From wounds of honey bee pupae, caused by the mite Varroa destructor, coccoid bacteria were isolated and identified as Melissococcus pluton. The bacterial isolate was grown anaerobically in sorbitol medium to produce a toxic compound that was purified on XAD columns, gelfiltration and preparative HPLC. The toxic agent was identified by GC-MS and FTICR-MS as tyramine. The toxicity of the isolated tyramine was tested by a novel mobility test using the protozoon Stylonychia lemnae. A concentration of 0.2 mg/ml led to immediate inhibition of mobility. In addition the toxicity was studied on honey bee larvae by feeding tyramine/water mixtures added to the larval jelly. The lethal dosis of tyramine on 4-5 days old bee larvae was determined as 0.3 mg/larvae when added as a volume of 20 microl to the larval food in brood cells. Several other biogenic amines, such as phenylethylamine, histamine, spermine, cadaverine, putrescine and trimethylamine, were tested as their hydrochloric salts for comparison and were found to be inhibitory in the Stylonychia mobility test at similar concentrations. A quantitative hemolysis test with human red blood cells revealed that tyramine and histamine showed the highest membranolytic activity, followed by the phenylethylamine, trimethylamine and spermine, while the linear diamines, cadaverine and putrescine, showed a significantly lower hemolysis when calculated on a molar amine basis. The results indicate that tyramine which is a characteristic amine produced by M. pluton in culture, is the causative agent of the observed toxic symptoms in bee larvae. Thus this disease, known as European foulbrood, is possibly an infection transmitted by the Varroa destructor mite.

  7. AMS and IRM studies in the late-variscan Santa Eulália Plutonic Complex (Ossa-Morena Zone, Portugal)

    Science.gov (United States)

    Sant'Ovaia, Helena; Gomes, Celeste; Carrilho Lopes, José; Nogueira, Pedro; Cruz, Claudia; Rocha, Armando

    2013-04-01

    The Santa Eulália Plutonic Complex (SEPC) is a calc-alkaline granitic body, with an area of 400 km2, and is located in the north of the Ossa Morena Zone of the Variscan Iberian sector, near the limit with the Central Iberian Zone. SEPC is considered late-Variscan because it cross-cuts the regional variscan structures. The host rocks are metamorphic formations from Upper Proterozoic to Lower Paleozoic. The SEPC has two main granitic facies with different compositions and textures. From the rim to the core, there is a medium-to coarse-grained pink granite (G0), which involves large elongated masses of mafic to intermediate rocks (M); and a central grey monzonitic granite (G1) which presents a dominant medium granular facies, and also a slight porphyritic texture close to G0. AMS and IRM studies were conducted to characterise these rocks, from 61 sampling sites: 29 in G0, 27 in G1 and 5 in M. The Km values range between 41.6 and 7343.7 x 10-6 SI in granitic rocks: G0, with Km > 10-3 SI (mean: 1357.4 x 10-6 SI) which supports the presence of magnetite, and G1 with Km< 10-4 SI (mean: 97.0 x 10-6 SI). In M, Km values are homogeneous with a mean of 620.9 x 10-6 SI. The magnetic anisotropy (P%) and the ellipsoid shape (T) were only determined in granites. The mean values of P% are 6.2% and 3.1% in G0 and G1, respectively. T shows the strongest oblate ellipsoids in central G1 (mean: 0.365) and slightly oblate in G0 (mean: 0.099). The magnetic foliations are subvertical ENE-WSW-striking in G0 and G1. Magnetic lineations are subvertical in G0 and moderately plunge to the SE in G1.The saturation IRM (SIRM) mean values are 9.345 A/m in G0, 0.027 A/m in G1 and 2.634 A/m in M. In G0 and M, the IRM acquisition curves show saturation between 0.3 and 0.4 T, followed by a small increase in increasing fields, suggesting that the main carrier of remanence is low magnetite or Ti-magnetite. In G1, the acquisition curves demonstrate paramagnetic and antiferromagnetic fractions, but a

  8. Alkaline carbonates in blast furnace process

    Directory of Open Access Journals (Sweden)

    P. Besta

    2014-10-01

    Full Text Available The production of iron in blast furnaces is a complex of physical, chemical and mechanical processes. The input raw materials contain not only metallic components, but also a number of negative elements. The most important negative elements include alkaline carbonates. They can significantly affect the course of the blast furnace process and thus the overall performance of the furnace. As a result of that, it is essential to accurately monitor the alkali content in the blast furnace raw materials. The article analyzes the alkali content in input and output raw materials and their impact on the blast furnace process.

  9. Alkaline chemistry of transuranium elements and technetium and the treatment of alkaline radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Delegard, C.H. [Westinghouse Hanford Co., Richland, WA (United States); Peretrukhin, V.F.; Shilov, V.P.; Pikaev, A.K. [Russian Academy of Sciences (Russian Federation). Inst. of Physical Chemistry

    1995-05-01

    Goal of this survey is to generalize the known data on fundamental physical-chemical properties of TRUs and Tc, methods for their isolation, and to provide recommendations that will be useful for partitioning them from alkaline high-level wastes.

  10. Low serum alkaline phosphatase activity in Wilson's disease.

    Science.gov (United States)

    Shaver, W A; Bhatt, H; Combes, B

    1986-01-01

    Low values for serum alkaline phosphatase activity were observed early in the course of two patients with Wilson's disease presenting with the combination of severe liver disease and Coombs' negative acute hemolytic anemia. A review of other cases of Wilson's disease revealed that 11 of 12 patients presenting with hemolytic anemia had values for serum alkaline phosphatase less than their respective sex- and age-adjusted mean values; in eight, serum alkaline phosphatase activity was less than the lower value for the normal range of the test. Low values for serum alkaline phosphatase were much less common in Wilson's disease patients with more chronic forms of presentation. Copper added in high concentration to serum in vitro did not have an important effect on serum alkaline phosphatase activity. The mechanism responsible for the decrease in serum alkaline phosphatase activity in patients is uncertain.

  11. DNA DAMAGE QUANTITATION BY ALKALINE GEL ELECTROPHORESIS.

    Energy Technology Data Exchange (ETDEWEB)

    SUTHERLAND,B.M.; BENNETT,P.V.; SUTHERLAND, J.C.

    2004-03-24

    Physical and chemical agents in the environment, those used in clinical applications, or encountered during recreational exposures to sunlight, induce damages in DNA. Understanding the biological impact of these agents requires quantitation of the levels of such damages in laboratory test systems as well as in field or clinical samples. Alkaline gel electrophoresis provides a sensitive (down to {approx} a few lesions/5Mb), rapid method of direct quantitation of a wide variety of DNA damages in nanogram quantities of non-radioactive DNAs from laboratory, field, or clinical specimens, including higher plants and animals. This method stems from velocity sedimentation studies of DNA populations, and from the simple methods of agarose gel electrophoresis. Our laboratories have developed quantitative agarose gel methods, analytical descriptions of DNA migration during electrophoresis on agarose gels (1-6), and electronic imaging for accurate determinations of DNA mass (7-9). Although all these components improve sensitivity and throughput of large numbers of samples (7,8,10), a simple version using only standard molecular biology equipment allows routine analysis of DNA damages at moderate frequencies. We present here a description of the methods, as well as a brief description of the underlying principles, required for a simplified approach to quantitation of DNA damages by alkaline gel electrophoresis.

  12. The effect of alkaline agents on retention of EOR chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, P.B.

    1991-07-01

    This report summarizes a literature survey on how alkaline agents reduce losses of surfactants and polymers in oil recovery by chemical injection. Data are reviewed for crude sulfonates, clean anionic surfactants, nonionic surfactants, and anionic and nonionic polymers. The role of mineral chemistry is briefly described. Specific effects of various alkaline anions are discussed. Investigations needed to improve the design of alkaline-surfactant-polymer floods are suggested. 62 refs., 28 figs., 6 tabs.

  13. Geochemistry of an island-arc plutonic suite: Wadi Dabr intrusive complex, Eastern Desert, Egypt

    Science.gov (United States)

    Abu El-Ela, Fawzy F.

    1997-05-01

    The Wadi Dabr intrusive complex, west of Mersa-Alam, Eastern Desert, Egypt ranges in composition from gabbro to diorite, quartz diorite and tonalite. The gabbroic rocks include pyroxene-horn blend e gabbro, hornblende gabbro, quartz-hornblende gabbro, metagabbro and amphibolite. Mineral chemistry data for the gabbroic rocks indicate that the composition of clinopyroxenes ranges from diopside to augite and the corresponding magma is equivalent to a volcanic-arc basalt. Plagioclase cores range from An 75 to An 34 for the gabbroic varieties, except for the metagabbro which has An 11-18. The brown amphiboles are primary phases and classified as calcic amphiboles, which range from tschermakitic hornblende to magnesiohornblende. Green hornblende and actinolite are secondary phases. Hornblende barometry and hornblende-plagioclase themometry for the gabbroic rocks estimate crystallisation conditions of 2-5 kb and 885-716°C. The intrusive rocks cover an extensive silica range (47.86-72.54 wt%) and do not exhibit simple straight-line variation on Harker diagrams for many elements (e.g. TiO 2, Al 2O 3, FeO ∗, MgP, CaO, P 2O 5, Cr, Ni, V, Sr, Zr and Y). Most of these elements exhibit two geochemical trends suggesting two magma sources. The gabbroic rocks are relatively enriched in large ion lithophile elements (K, Rb, Sr and Ba) and depleted in high field strength elements (Nb, Zr, Ti and Y) which suggest subduction-related magma. Rare earth element (REE) data demonstrate that the gabbroic rocks have a slight enrichment of light REE [(La/Yb) N=2.67-3.91] and depletion of heavy REE ((Tb/Yb) N=1.42-1.47], which suggest the parent magma was of relatively primitive mantle source. The diorites and tonalites are clearly calc-alkaline and have negative anomalies of Nb, Zr, and Y which also suggest subduction-related magma. They are related to continental trondhjemites in terms of RbSr, KNaCa, and to volcanic-arc granites in terms of Rband NbY. The Wadi Dabr

  14. Alkali-rich intrusive rocks in the Qinghai-Xizang Plateau and its vicinities as exemplified by Kuganzi and Taihe plutons

    Institute of Scientific and Technical Information of China (English)

    张玉泉; 谢应雯

    1997-01-01

    The alkali-rich intrusive rocks in the Qinghai-Xizang Plateau can be divided into two series in terms of dark-colored rock-forming minerals, petrochemical composition and trace elements: i ) sodic alkaline series rocks consisting of alkaline rocks and alkali granite which contain dark-colored minerals, such as aegirine augite, aegirine and riebeckite, and being petrochemically enriched in alkali and sodium but low in Ca, Sr and Ba; ii ) potassic alkaline series rocks consisting of alkaline rocks and alkali granite which contain non-alkaline dark-colored minerals (diopside, edenite), and being petrochemically enriched in alkali, K and Ca with high abundances of Sr and Ba.

  15. A 17 Ma onset for the post-collisional K-rich calc-alkaline magmatism in the Maghrebides: Evidence from Bougaroun (northeastern Algeria) and geodynamic implications

    Science.gov (United States)

    Abbassene, Fatiha; Chazot, Gilles; Bellon, Hervé; Bruguier, Olivier; Ouabadi, Aziouz; Maury, René C.; Déverchére, Jacques; Bosch, Delphine; Monié, Patrick

    2016-04-01

    Bougaroun is the largest pluton (~ 200 km2) in the 1200 km-long Neogene magmatic belt located along the Mediterranean coast of Maghreb. New U-Pb dating on zircons and K-Ar ages on whole rocks and separated minerals document its emplacement at 17 Ma within the Lesser Kabylian basement, a continental block that collided with the African margin during the Neogene. This Upper Burdigalian intrusion is therefore the oldest presently identified K-rich calc-alkaline massif in the whole Maghrebides magmatic lineament and marks the onset of its activity. The Bougaroun peraluminous felsic rocks display a very strong crustal imprint. Associated mafic rocks (LREE-enriched gabbros) have preserved the "orogenic" (subduction-related) geochemical signature of their mantle source. Older depleted gabbros cropping out at Cap Bougaroun are devoid of clear subduction-related imprint and yielded Ar-Ar hornblende ages of 27.0 ± 3.0 Ma and 23.3 ± 3.2 Ma. We suggest that they are related to the Upper Oligocene back-arc rifted margin and Early Miocene oceanic crust formation of the nearby Jijel basin, an extension of the Algerian basin developed during the African (Tethyan) slab rollback. The fact that the Bougaroun pluton intrudes exhumed Kabylian lower crustal units, mantle slices and flysch nappes indicates that the Kabylian margin was already stretched and in a post-collisional setting at 17 Ma. We propose a tectono-magmatic model involving an Early Miocene Tethyan slab breakoff combined with delamination of the edges of the African and Kabylian continental lithospheres. At 17 Ma, the asthenospheric thermal flux upwelling through the slab tear induced the thermal erosion of the Kabylian lithospheric mantle metasomatized during the previous subduction event and triggered its partial melting. We attribute the strong trace element and isotopic crustal signature of Bougaroun felsic rocks to extensive interactions between ascending mafic melts and the African crust underthrust beneath the

  16. Source of magma for Elet-Ozero pluton (NE Baltic Shield) - subduction or plume-related material?

    Science.gov (United States)

    Ryabchikov, Igor; Kogarko, Liya

    2016-04-01

    Eletozero pluton is located in the northeastern part of the Karelian Craton, it covers an area of about 100 km2 and cuts through Archaean granite-gneisses. The complex has a concentric zoned structure, the peripheral part being composed of a layered gabbro series; the central area is occupied by nepheline syenites. Mafic and ultramafic rocks in this intrusion often contain potassium feldspar (olivine monzonites and monzonites). Gabbroids are characterized by rhythmic layering expressed in the alternation of leucocratic layers predominantly composed of plagioclase and melanocratic layers with pyroxenes, olivine, titanomagnetite and ilmenite. The rocks of the pluton are enriched in highly incompatible elements by comparison with moderately incompatible elements: average primitive mantle normalized La/Lu ratio is 18.3. At the same time, all the rocks from Elet-Ozero massif including the most primitive ones (high Mg-numbers and high Ni contents) exhibit distinct positive Ba anomaly: mean chondrite normalized Ba/Th ratio is 15.3 (both elements have similar incompatibility-[1]). Enrichment of parent magma in Ba is also confirmed by the presence of high-Ba feldspars and micas in some samples of gabbroids. The most Ba-rich feldspar contains 75% of celsian component: K0.09Na0.04Ca0.008Sr0.04Ba0.75Al1.73Fe0.14Si2.20O8. Ba is a fluid mobile incompatible lithophile element that is probably the most sensitive indicator of subduction fluid addition to the mantle wedge. Thus, positive Ba anomaly suggests input of subduction related component into the source of Elet-Ozero magma. The presence of subduction related material in the lithosphere of Karelian craton has been proposed on the basis of Os isotope studies of mantle xenoliths from Finnish kimberlites [2]. The age of this subduction event is similar to the age of Elet-Ozero pluton. On the other hand, there are certain arguments in favor of connection of Elet-Ozero intrusive complex with mantle plume activity. In particular it

  17. Ti Mobility in Quartzite from the Eureka Valley-Joshua Flat-Beer Creek Pluton (EJB) Aureole in California, USA.

    Science.gov (United States)

    Student, J. J.; Morgan, S.

    2015-12-01

    The EJB pluton intruded into Paleozoic sandstone during the Jurassic leaving a well-exposed aureole. Quartzite was collected from the contact outward to investigate the response of Ti in sedimentary quartz to varying grades of metamorphism using EPMA and CL imaging. TitaniQ and Zr in rutile thermobarometers were applied to rutile bearing quartzite at 225, 500, and 1540 meters from the contact. Comparison CL images, including those of Harkless sandstone collected 15 km away and Harkless quartzite in the aureole reveal significant Ti mobility and a general smoothing of the Ti distribution in the quartzite. The CL images also reveal that the redistribution of Ti in the quartzite was incomplete. Discounting this, TitaniQ was applied using a Ti activity of 1.0 and a pressure of 2.75 kbars based on previous studies. In an effort to establish possible peak conditions, Ti was measured in the brightest CL quartz grain interiors, and the Zr was measured in surrounding rutile grains. The temperature calculations are inconsistent. At 225 meters, the Zr in rutile resulted in a temperature range from 662-762 °C (n=31) compared to a maximum temperature of 595 °C based on Ti in quartz. At 500 meters, rutile resulted in a range from 635-720 °C (n=44) compared to quartz at 525 °C. At 1540 meters, the rutile ranged from 650-710 °C (n=55) compared to quartz at 547 °C. The thermometric results may suggest that the aureole was extensively heated to above 500 °C even at 1.5 km from the pluton contact. This is supported by previous studies using other thermometers, thermal modeling, quartz deformation fabrics, and evidence of partial melting-type textures. In all likelihood though, the thermometric results in this study reflect components of inheritance of the original grains, lack of complete Ti re-equilibration due to sluggish diffusion of Ti during metamorphism, and the varying effects of water availability as related to the formation of distinct deformation textures.

  18. PLUTON: Three-group neutronic code for burnup analysis of isotope generation and depletion in highly irradiated LWR fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Lemehov, Sergei E; Suzuki, Motoe [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-08-01

    PLUTON is a three-group neutronic code analyzing, as functions of time and burnup, the change of radial profiles, together with average values, of power density, burnup, concentration of trans-uranium elements, plutonium buildup, depletion of fissile elements, and fission product generation in water reactor fuel rod with standard UO{sub 2}, UO{sub 2}-Gd{sub 2}O{sub 3}, inhomogeneous MOX, and UO{sub 2}-ThO{sub 2}. The PLUTON code, which has been designed to be run on Windows PC, has adopted a theoretical shape function of neutron attenuation in pellet, which enables users to perform a very fast and accurate calculation easily. The present code includes the irradiation conditions of the Halden Reactor which gives verification data for the code. The total list of trans-uranium elements included in the calculations consists of {sub 92}U{sup 233-239}, {sub 93}Np{sup 237-239}, {sub 94}Pu{sup 238-243}, {sub 95}Am{sup 241-244} (including isomers), and {sub 96}Cm{sup 242-245}. Poisoning fission products are represented by {sub 54}Xe{sup 131,133,135}, {sub 48}Cd{sup 113}, {sub 62}Sm{sup 149,151,152}, {sub 64}Gd{sup 154-160}, {sub 63}Eu{sup 153,155}, {sub 36}Kr{sup 83,85}, {sub 42}Mo{sup 95}, {sub 43}Tc{sup 99}, {sub 45}Rh{sup 103}, {sub 47}Ag{sup 109}, {sub 53}I{sup 127,129,131}, {sub 55}Cs{sup 133}, {sub 57}La{sup 139}, {sub 59}Pr{sup 141}, {sub 60}Nd{sup 143-150}, {sub 61}Pm{sup 147}. Fission gases and volatiles included in the code are {sub 36}Kr{sup 83-86}, {sub 54}Xe{sup 129-136}, {sub 52}Te{sup 125-130}, {sub 53}I{sup 127-131}, {sub 55}Cs{sup 133-137}, and {sub 56}Ba{sup 135-140}. Verification has been performed up to 83 GWd/tU, and a satisfactory agreement has been obtained. (author)

  19. Late Pleistocene pluton formation during the waning stages of the Altiplano-Puna ignimbrite flare-up

    Science.gov (United States)

    Tierney, C. R.; Schmitt, A. K.; Lovera, O. M.; de Silva, S. L.

    2015-12-01

    least 600 km3 of plutons underpinning each dome. The combined intrusive volume of 3,000 km3 results in a high intrusive to extrusive ratio of 75:1. This suggests that plutonic addition to the uppermost crust can be significant during the waning stages of high-flux events, although volcanic output is diminished.

  20. Characterizing fractured plutonic rocks of the Canadian shield for deep geological disposal of Canada`s radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Lodha, G.S.; Davison, C.C.; Gascoyne, M. [Atomic Energy of Canada Ltd. , Pinawa, MB (Canada). Whiteshell Labs.

    1998-09-01

    Since 1978 AECL has been investigating plutonic rocks of the Canadian Shield as a potential medium for the disposal of Canada`s nuclear fuel waste. During the last two years this study has been continued as part of Ontario Hydro`s used fuel disposal program. Methods have been developed for characterizing the geotechnical conditions at the regional scale of the Canadian Shield as well as for characterizing conditions at the site scale and the very near-field scale needed for locating and designing disposal vault rooms and waste emplacement areas. The Whiteshell Research Area (WRA) and the Underground Research Laboratory (URL) in southeastern Manitoba have been extensively used to develop and demonstrate the different scales of characterization methods. At the regional scale, airborne magnetic and electromagnetic surveys combined with LANDSAT 5 and surface gravity survey data have been helpful in identifying boundaries of the plutonic rocks , overburden thicknesses, major lineaments that might be geological structures, lithological contacts and depths of the batholiths. Surface geological mapping of exposed rock outcrops, combined with surface VLF/EM, radar and seismic reflection surveys were useful in identifying the orientation and depth continuity of low-dipping fracture zones beneath rock outcrops to a depth of 500 to 1000 m. The surface time-domain EM method has provided encouraging results for identifying the depth of highly saline pore waters. The regional site scale investigations at the WRA included the drilling of twenty deep boreholes (> 500 m) at seven separate study areas. Geological core logging combined with borehole geophysical logging, TV/ATV logging, flowmeter logging and full waveform sonic logging in these boreholes helped to confirm the location of hydro geologically important fractures, orient cores and infer the relative permeability of some fracture zones. Single-hole radar and crosshole seismic tomography surveys were useful to establish the

  1. Aeolus or Pluton?; Eole ou pluton?

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-07-01

    In the next years the french government will have to take great decisions in matter of energy and specifically electric power. This report aims to give an estimation of wind power channel in France supposing financial possibilities equivalent to those implemented for the EPR (European Pressurized Reactor) channel. After a presentation of the electric power industry in France, the two channels are compared. (A.L.B.)

  2. The link between volcanism and plutonism in epizonal magma systems; high-precision U–Pb zircon geochronology from the Organ Mountains caldera and batholith, New Mexico

    Science.gov (United States)

    Rioux, Matthew; Farmer, Lang; Bowring, Samuel; Wooton, Kathleen M.; Amato, Jeffrey M.; Coleman, Drew S.; Verplanck, Philip L.

    2016-01-01

    The Organ Mountains caldera and batholith expose the volcanic and epizonal plutonic record of an Eocene caldera complex. The caldera and batholith are well exposed, and extensive previous mapping and geochemical analyses have suggested a clear link between the volcanic and plutonic sections, making this an ideal location to study magmatic processes associated with caldera volcanism. Here we present high-precision thermal ionization mass spectrometry U–Pb zircon dates from throughout the caldera and batholith, and use these dates to test and improve existing petrogenetic models. The new dates indicate that Eocene volcanic and plutonic rocks in the Organ Mountains formed from ~44 to 34 Ma. The three largest caldera-related tuff units yielded weighted mean 206Pb/238U dates of 36.441 ± 0.020 Ma (Cueva Tuff), 36.259 ± 0.016 Ma (Achenback Park tuff), and 36.215 ± 0.016 Ma (Squaw Mountain tuff). An alkali feldspar granite, which is chemically similar to the erupted tuffs, yielded a synchronous weighted mean 206Pb/238U date of 36.259 ± 0.021 Ma. Weighted mean 206Pb/238U dates from the larger volume syenitic phase of the underlying Organ Needle pluton range from 36.130 ± 0.031 to 36.071 ± 0.012 Ma, and the youngest sample is 144 ± 20 to 188 ± 20 ka younger than the Squaw Mountain and Achenback Park tuffs, respectively. Younger plutonism in the batholith continued through at least 34.051 ± 0.029 Ma. We propose that the Achenback Park tuff, Squaw Mountain tuff, alkali feldspar granite and Organ Needle pluton formed from a single, long-lived magma chamber/mush zone. Early silicic magmas generated by partial melting of the lower crust rose to form an epizonal magma chamber. Underplating of the resulting mush zone led to partial melting and generation of a high-silica alkali feldspar granite cap, which erupted to form the tuffs. The deeper parts of the chamber underwent continued recharge and crystallization for 144 ± 20 ka after the

  3. World's youngest exposed granite pluton. ; Geological features, ages, and cooling model for Takidani granodiorite. Sekaiichi wakai roshutsu kakogan pluton. ; Takidani kako senryokugan no chishitsu nendai to reikyaku model

    Energy Technology Data Exchange (ETDEWEB)

    Harayama, S.

    1992-12-01

    This paper describes the Takidani granodiorite mainly on its dating results. The granodiorite is exposed over an area of 21 km[sup 2] In an axial area in the mountain range south to the Japanese North Alps. Its lithofacies changes from a granodiorite in a deep phase to a granite in an upper phase. Any of the lithofacies is very fresh not having been subjected to alterations, and bears no evidence of having been reheated. Four test pieces were sampled from this grandiorite, and were dated using the K-Ar method and the Pb-Sr method. The result showed a minimum value of 1.09 [plus minus] 0.03 Ma, and a maximum value of 1.93 [plus minus] 0.16 Ma. This granodiorite pluton age is the youngest among those having been reported from various parts of the world. The solidification age for this granodiorite at its shallow zone is estimated at 2.2 [plus minus] 0.3 Ma with reference to the age of pyroclastic flow deposits (about 2.4 Ma) which is assumed to have close spatial and chronological relation with the granodiorite in question. 46 refs., 3 figs., 4 tabs.

  4. Polyvinyl alcohol membranes as alkaline battery separators

    Science.gov (United States)

    Sheibley, D. W.; Gonzalez-Sanabria, O.; Manzo, M. A.

    1982-01-01

    Polyvinly alcohol (PVA) cross-linked with aldehyde reagents yields membranes that demonstrate properties that make them suitable for use as alkaline battery separators. Film properties can be controlled by the choice of cross-linker, cross-link density and the method of cross-linking. Three methods of cross-linking and their effects on film properties are discussed. Film properties can also be modified by using a copolymer of vinyl alcohol and acrylic acid as the base for the separator and cross-linking it similarly to the PVA. Fillers can be incorporated into the films to further modify film properties. Results of separator screening tests and cell tests for several variations of PBA films are discussed.

  5. Acylglucuronide in alkaline conditions: migration vs. hydrolysis.

    Science.gov (United States)

    Di Meo, Florent; Steel, Michele; Nicolas, Picard; Marquet, Pierre; Duroux, Jean-Luc; Trouillas, Patrick

    2013-06-01

    This work rationalizes the glucuronidation process (one of the reactions of the phase II metabolism) for drugs having a carboxylic acid moiety. At this stage, acylglucuronides (AG) metabolites are produced, that have largely been reported in the literature for various drugs (e.g., mycophenolic acid (MPA), diclofenac, ibuprofen, phenylacetic acids). The competition between migration and hydrolysis is rationalized by adequate quantum calculations, combing MP2 and density functional theory (DFT) methods. At the molecular scale, the former process is a real rotation of the drug around the glucuconic acid. This chemical-engine provides four different metabolites with various toxicities. Migration definitely appears feasible under alkaline conditions, making proton release from the OH groups. The latter reaction (hydrolysis) releases the free drug, so the competition is of crucial importance to tackle drug action and elimination. From the theoretical data, both migration and hydrolysis appear kinetically and thermodynamically favored, respectively.

  6. Hydrogen production by alkaline water electrolysis

    Directory of Open Access Journals (Sweden)

    Diogo M. F. Santos

    2013-01-01

    Full Text Available Water electrolysis is one of the simplest methods used for hydrogen production. It has the advantage of being able to produce hydrogen using only renewable energy. To expand the use of water electrolysis, it is mandatory to reduce energy consumption, cost, and maintenance of current electrolyzers, and, on the other hand, to increase their efficiency, durability, and safety. In this study, modern technologies for hydrogen production by water electrolysis have been investigated. In this article, the electrochemical fundamentals of alkaline water electrolysis are explained and the main process constraints (e.g., electrical, reaction, and transport are analyzed. The historical background of water electrolysis is described, different technologies are compared, and main research needs for the development of water electrolysis technologies are discussed.

  7. Advanced-capability alkaline fuel cell powerplant

    Science.gov (United States)

    Deronck, Henry J.

    The alkaline fuel cell powerplant utilized in the Space Shuttle Orbiter has established an excellent performance and reliability record over the past decade. Recent AFC technology programs have demonstrated significant advances in cell durability and power density. These capabilities provide the basis for substantial improvement of the Orbiter powerplant, enabling new mission applications as well as enhancing performance in the Orbiter. Improved durability would extend the powerplant's time between overhaul fivefold, and permit longer-duration missions. The powerplant would also be a strong candidate for lunar/planetary surface power systems. Higher power capability would enable replacement of the Orbiter's auxiliary power units with electric motors, and benefits mass-critical applications such as the National AeroSpace Plane.

  8. High Temperature and Pressure Alkaline Electrolysis

    DEFF Research Database (Denmark)

    Allebrod, Frank

    and oxygen with a new type of alkaline electrolysis cell at high temperatures and pressures. To perform measurements under high pressure and at elevated temperatures it was necessary to build a measurement system around an autoclave which could stand high temperatures up to 250 °C and pressures up to 200 bar...... as well as extremely caustic environments. Based on a literature study to identify resistant materials for these conditions, Inconel 600 was selected among the metals which are available for autoclave construction. An initial single atmosphere high temperature and pressure measurement setup was build...... comprising this autoclave. A second high temperature and pressure measurement setup was build based on experiences from the first setup in order to perform automatized measurements. The conductivity of aqueous KOH at elevated temperatures and high concentrations was investigated using the van der Pauw method...

  9. RES Hydrogen: efficient pressurised alkaline electrolysers

    DEFF Research Database (Denmark)

    Bowen, Jacob R.; Bentzen, Janet Jonna; Jørgensen, Peter Stanley;

    including BoP. Investigation of cathodes revealed highly heterogeneous microstructures and 3D microstructure quantification methods were developed. Nanometre scale -Ni(OH)2 formation was identified on tested cathode surfaces and is considered a potential degradation mechanism that is not presently well......The RESelyser project addresses issues associated with coupling alkaline electrolysis to renewable energy sources such as electrode stability and gas purity by implementing improved electrodes and a new separator membrane concept. The project aims to improve performance, operation pressure...... and reduce system cost. The project supports DTU Energy's activities on electrodes within the larger FCH-JU project. The overall project demonstrated: improved electrode efficiency also during cyclic operation, safe gas purity at a system pressure of 30 bar, 10 kW stack operation and estimated system costs...

  10. Enzymatic Hydrolysis of Alkaline Pretreated Coconut Coir

    Directory of Open Access Journals (Sweden)

    Akbarningrum Fatmawati

    2013-06-01

    Full Text Available The purpose of this research is to study the effect of concentration and temperature on the cellulose and lignin content, and the reducing sugars produced in the enzymatic hydrolysis of coconut coir. In this research, the coconut coir is pretreated using 3%, 7%, and 11% NaOH solution at 60oC, 80oC, and 100oC. The pretreated coir were assayed by measuring the amount of cellulose and lignin and then hydrolysed using Celluclast and Novozyme 188 under various temperature (30oC, 40oC, 50oC and pH (3, 4, 5. The hydrolysis results were assayed for the reducing sugar content. The results showed that the alkaline delignification was effective to reduce lignin and to increase the cellulose content of the coir. The best delignification condition was observed at 11% NaOH solution and 100oC which removed 14,53% of lignin and increased the cellulose content up to 50,23%. The best condition of the enzymatic hydrolysis was obtained at 50oC and pH 4 which produced 7,57 gr/L reducing sugar. © 2013 BCREC UNDIP. All rights reservedReceived: 2nd October 2012; Revised: 31st January 2013; Accepted: 6th February 2013[How to Cite: Fatmawati, A., Agustriyanto, R., Liasari, Y. (2013. Enzymatic Hydrolysis of Alkaline Pre-treated Coconut Coir. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 34-39 (doi:10.9767/bcrec.8.1.4048.34-39[Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4048.34-39] | View in  |

  11. On electrochemical devices using alkaline polymer electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, L. [Wuhan Univ., Wuhan (China). Dept. of Chemistry

    2010-07-01

    Solid polymer electrolytes (SPEs) enable a compact assembly of fuel cells and electrolyzers, thereby increasing the space-specific conversion efficiency and avoiding electrolyte leakage. The most widely used SPE in proton exchange membrane fuel cells (PEMFC) and chloro-alkali electrolyzers is Nafion. However, this strongly acidic polyelectrolyte allows only noble metals to be used as the catalysts in the electrochemical devices, which poses a problem in terms of price and resource limits. In principle, alkaline polymer electrolytes (APEs) should be used to eliminate the dependence on noble metal catalysts. The general structure of alkaline polymer electrolytes is a positively charged polymer, notably, a polymer chain attached with fixed cations such as quaternary ammonia group, and dissociated anion, OH-, to act as the charge carrier. This presentation described the challenges of developing APEs in terms of the chemical stability of quaternary ammonia group, the mobility of OH-, and high ionic concentration. The authors have been working on developing high-performance APEs since 2001. The most recent APEs were quaternary ammonia polysulfone (QAPS), which were found to be suitable for fuel cell and electrolyzer applications. The ionic conductivity was high and the crosslinked membrane had excellent mechanical strength, enabling operation at 90 degrees C. Non-precious metal catalysts were used in the APEs. For APE-based fuel cells (APEFC), chromium decorated nickel was used as the anode catalyst for hydrogen oxidation, and silver was used as the cathode catalyst for oxygen reduction. The preliminary performance of such an APEFC with non-Pt catalysts was found to be much better than that of traditional water electrolyzers using KOH solutions. 2 refs.

  12. The Early Andean Magmatic Province (EAMP): 40Ar/ 39Ar dating on Mesozoic volcanic and plutonic rocks from the Coastal Cordillera, northern Chile

    Science.gov (United States)

    Oliveros, Verónica; Féraud, Gilbert; Aguirre, Luis; Fornari, Michel; Morata, Diego

    2006-10-01

    The Early Andean Magmatic Province (EAMP), consists of about 150 000 km 3 of volcanic and plutonic units in the Coastal Cordillera of northern Chile and southern Peru and represents a major magmatic Mesozoic event in the world, for which the precise age of the thick volcanic series was unknown. Thirty 40Ar/ 39Ar analyses were carried out on primary mineral phases of volcanic and plutonic rocks from northern Chile (18°30'-24°S). Reliable plateau and "mini plateau" ages were obtained on plagioclase, amphibole and biotite from volcanic and plutonic rocks, despite widespread strong alteration degree. In the Arica, Tocopilla and Antofagasta (700 km apart) regions, the ages obtained on lava flows constrain the volcanic activity between 164 and 150 Ma and no N-S migration of volcanism is observed. The uppermost lava flows of the volcanic sequence at the type locality of the La Negra Formation extruded at ca. 153-150 Ma, suggesting the end of the volcanic activity of the arc at that time. The oldest volcanic activity occurred probably at ca. 175-170 Ma in the Iquique area, although no plateau age could be obtained. The plutonic bodies of the same regions were dated between ca. 160 and 142 Ma, indicating that they were partly contemporaneous with the volcanic activity. At least one volcanic pulse around 160 Ma is evidenced over the entire investigated reach of the EAMP, according to the ages found in Arica, Tocopilla, Michilla and Mantos Blancos regions. The episodic emplacement of huge amounts of subduction related volcanism is observed throughout the whole Andean history and particularly during the Jurassic (southern Peru, northern Chile and southern Argentina). These events probably correspond to periodic extensional geodynamic episodes, as a consequence of particular subduction conditions, such as change of obliquity of the convergence, change in the subduction angle, slab roll back effect or lower convergence rate, that remain to be precisely defined.

  13. Mesoproterozoic island arc magmatism along the south-eastern margin of the Indian Plate: Evidence from geochemistry and zircon U-Pb ages of mafic plutonic complexes

    Science.gov (United States)

    Subramanyam, K. S. V.; Santosh, M.; Yang, Qiong-Yan; Zhang, Ze-ming; Balaram, V.; Reddy, U. V. B.

    2016-11-01

    The Prakasam Igneous Province within the Nellore Schist Belt (NSB) preserves important imprints of mafic magmatism along the south-eastern margin of the Indian plate. Here we report petrology, geochemistry and zircon U-Pb age data from three gabbro plutons namely Purimetla, Kanigiri and P C Palle which intruded into the high grade rocks of the region. LA-ICP-MS U-Pb data on zircons from the three plutons reveal prominent late Mesoproterozoic ages of 1334 ± 15 Ma, 1338 ± 27 Ma and 1251.2 ± 9.4 Ma. The cumulative 207Pb/206Pb mean age of 1315 ± 11 Ma is interpreted to represent the timing of mafic magmatism in the Prakasam Igneous Province. These rocks show adcumulus to mesocumulus and poikilitic textures indicating fractional crystallization of plagioclase and clinopyroxenes in the Purimetla pluton whereas the Kanigiri and P C Palle intrusions possess hornblende and biotite suggesting the role of water during partial melting. The rocks show LREE enrichment (∑LREE/∑HREE = 2.2-15.0), marked Eu-anomalies (Eu/Eu∗ = 0.8-2.2) and fractionated patterns (LaN/YbN = 3-79). Primitive mantle normalised trace element spider diagrams indicate subduction modified arc signatures with LILE enrichment and depletion of Nb, Ti and Zr relative to Th and La. Tectonic discrimination diagrams show arc magmatic affinities for the three gabbro plutons consistent with subduction zone setting. We propose a tectonic model involving intra oceanic island arc accretion during late Mesoproterozoic along the eastern margin of the Indian continent.

  14. An integrated zircon geochronological and geochemical investigation into the Miocene plutonic evolution of the Cyclades, Aegean Sea, Greece: Part 1: Geochronology

    Science.gov (United States)

    Bolhar, Robert; Ring, Uwe; Allen, Charlotte M.

    2010-11-01

    We use 369 individual U-Pb zircon ages from 14 granitoid samples collected on five islands in the Cyclades in the Aegean Sea, Greece, for constraining the crystallisation history of I- and S-type plutons above the retreating Hellenic subduction zone. Miocene magmatism in the Cyclades extended over a time span from 17 to 11 Ma. The ages for S-type granites are systematically ~2 million years older than those for I-type granites. Considering plutons individually, the zircon data define age spectra ranging from simple and unimodal to complex and multimodal. Seven of the 14 investigated samples yield more than one distinct zircon crystallisation age, with one I-type granodiorite sample from Mykonos Island representing the most complex case with three resolvable age peaks. Two samples from S-type granites on Ikaria appear to have crystallised zircon over 2-3 million years, whereas for the majority of individual samples with multiple zircon age populations the calculated ages deviate by 1-1.5 million years. We interpret our age data to reflect a protracted history involving initial partial melting at deeper lithospheric levels, followed by crystallisation and cooling at shallower crustal levels. Our study corroborates published research arguing that pluton construction is due to incremental emplacement of multiple magma pulses over a few million years. Assuming that multiple age peaks of our 14 samples can indeed serve to quantify time spans for magmatic emplacement, our data suggest that Aegean plutons were constructed over a few million years. Our tectonic interpretation of the U-Pb ages is that the S-type granites resulted from partial melting and migmatisation of the lower crust, possibly starting at ~23 Ma. The I-type granites and associated mafic melts are interpreted to reflect the magmatic arc stage in the Cyclades starting at ~15 Ma.

  15. Petrology and LA-ICP-MS Zircon U-Pb Geochronology of the Qianjinchang Pluton, Southeastern Inner Mongolia%内蒙古前进场岩体岩石学与锆石U-Pb年代学研究

    Institute of Scientific and Technical Information of China (English)

    徐佳佳; 赖勇; 崔栋; 鲁彬

    2012-01-01

    The Qianjinchang biotite granite from southeastern Inner Mongolia is located in the suture zone between the Siberian and North China Cratons. The Daolundaba Cu-W-Sn polymetallic deposit formed at the contact zone between the north-west margin of the pluton and the Lower Permian Linxi Formation. The biotite granite is high-K calc-alkaline and peraluminous, with Na2O+K2O: 6.12% to 9.31%, Al2O3: 14.42% to 15.59%, A/CNK: 1.09 to 1.22, and a mean 5value of 2.41. The rock samples lie within the S-type granite region in the ACF plot. They are depleted in Sr (89.91 to 192.80 μg/g), Ba, Eu (δEu: 0.46 to 0.81) and δREE (102.65 to 237.92 μg/g), but slightly enriched in Yb (2.17 to 3.46 μg/g) and La, consistent with the characteristics of S-type granites. The rocks further fall in the region of post-collisional granite in the Rb vs. Y+Nb diagram. LA-ICP-MS zircon U-Pb geochronology shows that the pluton emplaced at (273±7.7) to (278 ±4.3) Ma. These Permian granite rocks probably formed in an extensional setting that postdated the collision between the Siberian and North China Cratons.%前进场黑云母花岗岩岩体位于内蒙古东南部,华北板块与西伯利亚板块碰撞的缝合部位。岩体北西边缘与林西组地层的接触带发育道伦达坝中型铜-钨-锡多金属岩浆热液矿床。岩石地球化学研究表明,黑云母花岗岩为高钾钙碱性系列的过铝质花岗岩,Na2O+K2O含量为6.12%-9.31%,Al2O3含量为14.42%-15.59%,A/CNK值为1.09-1.22,万均值为2.41,在花岗岩ACF图解中落人s型花岗岩区。全岩总稀土含量为102.65~237.92μg/g,低Sr(89.91-192.80μg/g)高Yb(2.17~3.46μg/g),δEu值为0.46~0.81,亏损Ba,Sr,Eu,富集La,显示S型花岗岩特征,在Rb-(Y+Nb)图解中显示后碰撞岩浆地球化学性质。利用LA-ICP-MS锆石U-Pb年代学方法,确定岩体形成年代为(273±7.7)-(278±4.3)Ma,在早

  16. Petrogenesis and significance of the Hongshan syenitic pluton,South Taihang: zircon SHRIMP U-Pb age, chemical compositions and Sr-Nd isotopes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The Hongshan syenitic pluton (South Taihang) is mainly made up of hornblende syenite and minor granite. SHRIMP zircon dating yields a U-Pb age of 135 ± 2.7 Ma for the emplacement of the pluton, while biotite Rb-Sr isotopic data give an isochron of 120.3 ± 2.4 Ma. Hongshan syenites show low silica, high alkalis and LILE such as Sr, and exhibit negligible Eu anomalies or slightly positive anomalies in the REE patterns. The syenites show quite enriched isotopic compositions with Isr from 0. 7052 to 0. 7102 and εNd( t ) from - 7.5 to - 11. 1. Petrogenesis of the pluton can be that partial melting of an enriched lithospheric mantle gave birth to an alkali basaltic magma, which subsequently underplated in the lower crust and experienced a coupled fractionation of ferromagnesian phases like pyroxene and hornblende and minor ( < 10 % ) contamination of lower continental crust, producing the Hongshan syenites that partially evolved into granite through combined fractionation of hornblende and feldspar. Our data are not in agreement with a previous model that the syenites originated from melting of lower crust in a thickened crust circumstance, and thus do not support the speculation of "East China Plateau" in the Mesozoic.

  17. LA-ICPMS Zircon U-Pb Dating for Three Indosinian Granitic Plutons from Central Hunan and Western Guangdong Provinces and Its Petrogenetic Implications

    Institute of Scientific and Technical Information of China (English)

    PENG Bingxia; WANG Yuejun; FAN Weiming; PENG Touping; LIANG Xinquan

    2006-01-01

    The LA-ICPMS zircon U-Pb geochronology of three typically Indosinian granitic plutons yielded weighted mean 206Pb/238U ages of 214.1±5.9 Ma and 210.3±4.7 Ma for the biotite monzonitic granites from the Xiema and Xiangzikou plutons in Hunan Province, and 205.3±1.6 Ma for biotite granite from the Napeng pluton, western Guandong Province, respectively, showing a similar late Indosinian age of crystallization. In combination with other geochronological data from Indosinian granites within the South China Block (SCB), it is proposed that those late Indosinian granites with an age of ~210 Ma and the early Indosinian granites (230-245 Ma) have the similar petrogenesis in identical tectonic setting. The Indosinian granites within the SCB might be the products of anatexis of the thickening crust in a compressive regime. These data provide a further understanding for the temporal and spatial distribution of the Indosinian granites and the dynamic evolution of the SCB.

  18. Increased river alkalinization in the Eastern U.S

    Science.gov (United States)

    Kaushal, S.; Likens, G. E.; Utz, R.; Pace, M.; Grese, M.; Yepsen, M.

    2013-12-01

    The interaction between human activities and watershed geology is accelerating long-term changes in the carbon cycle of rivers. We evaluated changes in bicarbonate alkalinity, a product of chemical weathering, and tested for long-term trends at 97 sites in the eastern United States draining over 260,000 km2. We observed statistically significant increasing trends in alkalinity at 62 of the 97 sites, while remaining sites exhibited no significant decreasing trends. Over 50% of study sites also had statistically significant increasing trends in concentrations of calcium (another product of chemical weathering) where data were available. River alkalinization rates were significantly related to watershed carbonate lithology, acid deposition, and topography. These 3 variables explained ~40% of variation in river alkalinization rates. The strongest predictor of river alkalinization rates was carbonate lithology. The most rapid rates of river alkalinization occurred at sites with highest inputs of acid deposition and highest elevation. The rise of alkalinity in many rivers throughout the eastern U.S. suggests human-accelerated chemical weathering, in addition to previously documented impacts of mining and land use. Increased river alkalinization has major environmental implications including impacts on water hardness and salinization of drinking water, alterations of air-water exchange of CO2, coastal ocean acidification, and the influence of bicarbonate availability on primary production.

  19. Space-time variability of alkalinity in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    G. Cossarini

    2014-09-01

    Full Text Available The paper provides a basin assessment of the spatial distribution of ocean alkalinity in the Mediterranean Sea. The assessment is made using a 3-D transport-biogeochemical-carbonate model to integrate the available experimental findings, which also constrains model output. The results indicate that the Mediterranean Sea shows alkalinity values that are much higher than those observed in the Atlantic Ocean on a basin-wide scale. A marked west-to-east surface gradient of alkalinity is reproduced as a response to the terrestrial discharges, the mixing effect with the Atlantic water entering from the Gibraltar Strait and the Black Sea water from Dardanelles, and the surface flux of evaporation minus precipitation. Dense water production in marginal seas (Adriatic and Aegean Seas, where alkaline inputs are relevant, and the Mediterranean thermohaline circulation sustains the west-to-east gradient along the entire water column. In the surface layers, alkalinity has a relevant seasonal cycle (up to 40 μmol kg−1 that is driven both by physical and biological processes. A comparison of alkalinity vs. salinity indicates that different regions present different relationships. In regions of freshwater influence, the two measures are negatively correlated due to riverine alkalinity input, whereas they are positively correlated in open seas. Alkalinity always is much higher than in the Atlantic waters, which might indicate a higher than usual buffering capacity towards ocean acidification, even at high concentrations of dissolved inorganic carbon.

  20. Increased river alkalinization in the Eastern U.S.

    Science.gov (United States)

    Kaushal, Sujay S; Likens, Gene E; Utz, Ryan M; Pace, Michael L; Grese, Melissa; Yepsen, Metthea

    2013-09-17

    The interaction between human activities and watershed geology is accelerating long-term changes in the carbon cycle of rivers. We evaluated changes in bicarbonate alkalinity, a product of chemical weathering, and tested for long-term trends at 97 sites in the eastern United States draining over 260,000 km(2). We observed statistically significant increasing trends in alkalinity at 62 of the 97 sites, while remaining sites exhibited no significant decreasing trends. Over 50% of study sites also had statistically significant increasing trends in concentrations of calcium (another product of chemical weathering) where data were available. River alkalinization rates were significantly related to watershed carbonate lithology, acid deposition, and topography. These three variables explained ~40% of variation in river alkalinization rates. The strongest predictor of river alkalinization rates was carbonate lithology. The most rapid rates of river alkalinization occurred at sites with highest inputs of acid deposition and highest elevation. The rise of alkalinity in many rivers throughout the Eastern U.S. suggests human-accelerated chemical weathering, in addition to previously documented impacts of mining and land use. Increased river alkalinization has major environmental implications including impacts on water hardness and salinization of drinking water, alterations of air-water exchange of CO2, coastal ocean acidification, and the influence of bicarbonate availability on primary production.

  1. Alkaline stability of quaternary ammonium cations for alkaline fuel cell membranes and ionic liquids.

    Science.gov (United States)

    Marino, M G; Kreuer, K D

    2015-02-01

    The alkaline stability of 26 different quaternary ammonium groups (QA) is investigated for temperatures up to 160 °C and NaOH concentrations up to 10 mol L(-1) with the aim to provide a basis for the selection of functional groups for hydroxide exchange membranes in alkaline fuel cells and of ionic-liquid cations stable in basic conditions. Most QAs exhibit unexpectedly high alkaline stability with the exception of aromatic cations. β-Protons are found to be far less susceptible to nucleophilic attack than previously suggested, whereas the presence of benzyl groups, nearby hetero-atoms, or other electron-withdrawing species promote degradation reactions significantly. Cyclic QAs proved to be exceptionally stable, with the piperidine-based 6-azonia-spiro[5.5]undecane featuring the highest half-life at the chosen conditions. Absolute and relative stabilities presented herein stand in contrast to literature data, the differences being ascribed to solvent effects on degradation.

  2. The impact of geology on the migration of fluorides in mineral waters of the Bukulja and Brajkovac pluton area, Serbia

    Directory of Open Access Journals (Sweden)

    Papić Petar

    2012-01-01

    Full Text Available One of the hydrogeochemical parameters that classify groundwater as mineral water is the content of fluoride ions. Their concentration is both important and limited for bottled mineral waters. Hydrochemical research of mineral waters in the surrounding area of Bukulja and Brajkovac pluton, in central Serbia, was conducted in order to define the chemical composition and genesis of these waters. They are carbonated waters, with content of fluoride ranging from 0.2 up to 6.6 mg/L. Since hydrochemical analyses showed variations in the major water chemistry, it was obvious that, apart from hydrochemical research, some explorations of the structure of the regional terrain would be inevitable. For these purposes, some additional geological research was performed, creating an adequate basis for the interpretation of the genesis of these carbonated mineral waters. The results confirmed the significance of the application of hydrochemical methods in the research of mineral waters. The work tended to emphasize that “technological treatment” for decreasing the concentration of fluoride in mineral waters occurs in nature, indicating the existence of natural defluoridization. [Projekat Ministarstva nauke Republike Srbije, br. 43004

  3. Interaction between two contrasting magmas in the Albtal pluton (Schwarzwald, SW Germany): textural and mineral-chemical evidence

    Science.gov (United States)

    Michel, Lorenz; Wenzel, Thomas; Markl, Gregor

    2016-07-01

    The magmatic evolution of the Variscan Albtal pluton, Schwarzwald, SW Germany, is explored using detailed textural observations and the chemical composition of plagioclase and biotite in both granite and its mafic magmatic enclaves (MMEs). MMEs probably formed in a two-step process. First, mafic magma intruded a granitic magma chamber and created a boundary layer, which received thermal and compositional input from the mafic magma. This is indicated by corroded "granitic" quartz crystals and by large "granitic" plagioclase xenocrysts, which contain zones of higher anorthite and partly crystallized from a melt of higher Sr content. Texturally, different plagioclase types (e.g. zoned and inclusion-rich types) correspond to different degrees of overprint most likely caused by a thermal and compositional gradient in the boundary layer. The intrusion of a second mafic magma batch into the boundary layer is recorded by a thin An50 zone along plagioclase rims that crystallized from a melt enriched in Sr. Most probably, the second mafic intrusion caused disruption of the boundary layer, dispersal of the hybrid magma in the granite magma and formation of the enclaves. Rapid thermal quenching of the MMEs in the granite magma is manifested by An30 overgrowths on large plagioclase grains that contain needle apatites. Our results demonstrate the importance of microtextural investigations for the reconstruction of possible mixing end members in the formation of granites.

  4. Phosphatidylinositol anchor of HeLa cell alkaline phosphatase

    Energy Technology Data Exchange (ETDEWEB)

    Jemmerson, R.; Low, M.G.

    1987-09-08

    Alkaline phosphatase from cancer cells, HeLa TCRC-1, was biosynthetically labeled with either /sup 3/H-fatty acids or (/sup 3/H)ethanolamine as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography of immunoprecipitated material. Phosphatidylinositol-specific phospholipase C (PI-PLC) released a substantial proportion of the /sup 3/H-fatty acid label from immunoaffinity-purified alkaline phosphatase but had no effect on the radioactivity of (/sup 3/H)ethanolamine-labeled material. PI-PLC also liberated catalytically active alkaline phosphatase from viable cells, and this could be selectively blocked by monoclonal antibodies to alkaline phosphatase. However, the alkaline phosphatase released from /sup 3/H-fatty acid labeled cells by PI-PLC was not radioactive. By contrast, treatment with bromelain removed both the /sup 3/H-fatty acid and the (/sup 3/H)ethanolamine label from purified alkaline phosphatase. Subtilisin was also able to remove the (/sup 3/H)ethanolamine label from the purified alkaline phosphatase. The /sup 3/H radioactivity in alkaline phosphatase purified from (/sup 3/H)ethanolamine-labeled cells comigrated with authentic (/sup 3/H)ethanolamine by anion-exchange chromatography after acid hydrolysis. The data suggest that the /sup 3/H-fatty acid and (/sup 3/H)ethanolamine are covalently attached to the carboxyl-terminal segment since bromelain and subtilisin both release alkaline phosphatase from the membrane by cleavage at that end of the polypeptide chain. The data are consistent with findings for other proteins recently shown to be anchored in the membrane through a glycosylphosphatidylinositol structure and indicate that a similar structure contributes to the membrane anchoring of alkaline phosphatase.

  5. The effect of irrigated rice cropping on the alkalinity of two alkaline rice soils in the Sahel

    NARCIS (Netherlands)

    Asten, van P.J.A.; Zelfde, van 't J.A.; Zee, van der S.E.A.T.M.; Hammecker, C.

    2004-01-01

    Irrigated rice cropping is practiced to reclaim alkaline-sodic soils in many parts of the world. This practice is in apparent contrast with earlier studies in the Sahel, which suggests that irrigated rice cropping may lead to the formation of alkaline-sodic soils. Soil column experiments were done w

  6. The Choiyoi Group from central Argentina: a subalkaline transitional to alkaline association in the craton adjacent to the active margin of the Gondwana continent

    Science.gov (United States)

    Llambías, Eduardo J.; Quenardelle, Sonia; Montenegro, Teresita

    2003-08-01

    Permian and Lower Triassic igneous rocks from La Pampa province, central Argentina, are part of the Choiyoi Group, whose extension in Argentina exceeds 500,000 km 2. In La Pampa, the distribution of these outcrops occurs along a NW-SE belt that cuts obliquely across the N-S structures of the Lower Paleozoic rocks. The basement of the Choiyoi Group in western La Pampa consists of Mesoproterozoic to Lower Paleozoic rocks that form part of the exotic Cuyania terrane. In central La Pampa, the basement consists of Lower Paleozoic igneous and metamorphic rocks affected by the Lower Paleozoic Famatinian orogeny. The Choiyoi Group from La Pampa shares features with the Choiyoi Group elsewhere, such as an abundance of mesosilicic to silicic ignimbrites, subvolcanic domes, and granite plutons emplaced at sallow levels. In La Pampa, we recognize two suites: shoshonitic and trachydacitic to rhyolitic. The shoshonite suite is overlain by trachydacites and rhyolites. The plutonic rocks that belong to the cupola of the intrusive bodies are monzogranitic. The most significant difference between the Choiyoi Group from La Pampa and that from the Cordillera Frontal and the San Rafael block is that the San Rafael orogenic phase (Lower Permian) is not obvious in La Pampa. Therefore, we cannot attribute to the Choiyoi Group a postorogenic character, as in the Cordillera Frontal or the San Rafael Block. This difference in the tectonic setting is reflected in the composition of the igneous rocks of La Pampa, in that they generally have a higher alkali content with respect to silica, a weak enrichment in TiO 2, and a depletion in CaO. Both suites are transitional from subalkaline to alkaline series. The shoshonitic suite is rich in clinopyroxene and apatite. Whole-rock compositions have high content of P 2O 5 (0.5-3.9%) and Sr (1320-1890 ppm). Zr is weakly enriched (273-502 ppm), and Nb (29-37 ppm) is depleted. The Th (16-45 ppm) and U (3-14 ppm) content is high. We postulate a crustal

  7. Batteries: from alkaline to zinc-air.

    Science.gov (United States)

    Dondelinger, Robert M

    2004-01-01

    There is no perfect disposable battery--one that will sit on the shelf for 20 years, then continually provide unlimited current, at a completely constant voltage until exhausted, without producing heat. There is no perfect rechargeable battery--one with all of the above characteristics and will also withstand an infinite overcharge while providing an equally infinite cycle life. There are only compromises. Every battery selection is a compromise between the ideally required characteristics, the advantages, and the limitations of each battery type. General selection of a battery type to power a medical device is largely outside the purview of the biomed. Initially, these are engineering decisions made at the time of medical equipment design and are intended to be followed in perpetuity. However, since newer cell types evolve and the manufacturer's literature is fixed at the time of printing, some intelligent substitutions may be made as long as the biomed understands the characteristics of both the recommended cell and the replacement cell. For example, when the manufacturer recommends alkaline, it is usually because of the almost constant voltage it produces under the devices' design load. Over time, other battery types may be developed that will meet the intent of the manufacturer, at a lower cost, providing longer operational life, at a lower environmental cost, or with a combination of these advantages. In the Obstetrical Doppler cited at the beginning of this article, the user had put in carbon-zinc cells, and the biomed had unknowingly replaced them with carbonzinc cells. If the alkaline cells recommended by the manufacturer had been used, there would have been the proper output voltage at the battery terminals when the [table: see text] cells were at their half-life. Instead, the device refused to operate since the battery voltage was below presumed design voltage. While battery-type substitutions may be easily and relatively successfully made in disposable

  8. Microbial thiocyanate utilization under highly alkaline conditions.

    Science.gov (United States)

    Sorokin, D Y; Tourova, T P; Lysenko, A M; Kuenen, J G

    2001-02-01

    Three kinds of alkaliphilic bacteria able to utilize thiocyanate (CNS-) at pH 10 were found in highly alkaline soda lake sediments and soda soils. The first group included obligate heterotrophs that utilized thiocyanate as a nitrogen source while growing at pH 10 with acetate as carbon and energy sources. Most of the heterotrophic strains were able to oxidize sulfide and thiosulfate to tetrathionate. The second group included obligately autotrophic sulfur-oxidizing alkaliphiles which utilized thiocyanate nitrogen during growth with thiosulfate as the energy source. Genetic analysis demonstrated that both the heterotrophic and autotrophic alkaliphiles that utilized thiocyanate as a nitrogen source were related to the previously described sulfur-oxidizing alkaliphiles belonging to the gamma subdivision of the division Proteobacteria (the Halomonas group for the heterotrophs and the genus Thioalkalivibrio for autotrophs). The third group included obligately autotrophic sulfur-oxidizing alkaliphilic bacteria able to utilize thiocyanate as a sole source of energy. These bacteria could be enriched on mineral medium with thiocyanate at pH 10. Growth with thiocyanate was usually much slower than growth with thiosulfate, although the biomass yield on thiocyanate was higher. Of the four strains isolated, the three vibrio-shaped strains were genetically closely related to the previously described sulfur-oxidizing alkaliphiles belonging to the genus Thioalkalivibrio. The rod-shaped isolate differed from the other isolates by its ability to accumulate large amounts of elemental sulfur inside its cells and by its ability to oxidize carbon disulfide. Despite its low DNA homology with and substantial phenotypic differences from the vibrio-shaped strains, this isolate also belonged to the genus Thioalkalivibrio according to a phylogenetic analysis. The heterotrophic and autotrophic alkaliphiles that grew with thiocyanate as an N source possessed a relatively high level of cyanase

  9. Growth of plutons by incremental emplacement of sheets in crystal-rich host: Evidence from Miocene intrusions of the Colorado River region, Nevada, USA

    Science.gov (United States)

    Miller, C.F.; Furbish, D.J.; Walker, B.A.; Claiborne, L.L.; Koteas, G.C.; Bleick, H.A.; Miller, J.S.

    2011-01-01

    Growing evidence supports the notion that plutons are constructed incrementally, commonly over long periods of time, yet field evidence for the multiple injections that seem to be required is commonly sparse or absent. Timescales of up to several million years, among other arguments, indicate that the dominant volume does not remain largely molten, yet if growing plutons are constructed from rapidly solidifying increments it is unlikely that intrusive contacts would escape notice. A model wherein magma increments are emplaced into melt-bearing but crystal-rich host, rather than either solid or crystal-poor material, provides a plausible explanation for this apparent conundrum. A partially solidified intrusion undoubtedly comprises zones with contrasting melt fraction and therefore strength. Depending on whether these zones behave elastically or ductilely in response to dike emplacement, intruding magma may spread to form sheets by either of two mechanisms. If the melt-bearing host is elastic on the relevant timescale, magma spreads rather than continuing to propagate upward, where it encounters a zone of higher rigidity (higher crystal fraction). Similarly, if the dike at first ascends through rigid, melt-poor material and then encounters a zone that is weak enough (poor enough in crystals) to respond ductilely, the ascending material will also spread because the dike tip ceases to propagate as in rigid material. We propose that ascending magma is thus in essence trapped, by either mechanism, within relatively crystal-poor zones. Contacts will commonly be obscure from the start because the contrast between intruding material (crystal-poorer magma) and host (crystal-richer material) is subtle, and they may be obscured even further by subsequent destabilization of the crystal-melt framework. Field evidence and zircon zoning stratigraphy in plutons of the Colorado River region of southern Nevada support the hypothesis that emplacement of magma replenishments into a

  10. Titratable Acidity and Alkalinity of Red Soil Surfaces

    Institute of Scientific and Technical Information of China (English)

    SHAOZONG-CHEN; HEQUN; 等

    1993-01-01

    The surfaces of red soils have an apparent amphoteric character,carrying titratable acidity and titratable alkalinity simultaneously.The titratable acidity arises from deprotonation of hydroxyl groups of hydrous oxide-type surfaces and dissociation of weak-acid functional groups of soil organic matter,while the titratable alkalinity is derived from release of hydroxyl groups of hydrous oxide-type surfaces.The titratable acidity and titratable alkalinity mainly depended on the composition and content of iron and aluminum oxides in the soils.The results showed that the titratable acidity and titratable alkalinity were in significantly positive correlation not only with the content of amorphous aluminum oxide(Alo) and iron oxide(Feo) extracted with acid ammonium oxalate solution,free iron oxide(Fed) extracted with sodium dithionite-citrate-bicarbonate(DCB) and clays,but also with the zero point of charge (ZPC) of the samples.Organic matter made an important contribution to the titratable acidity.the titratable alkalinity was closely correlated with the amount of fluoride ions adsorbed.The titratable acidity and titratable alkalinity of red soils were influenced by parent materials,being in the order of red soil derived from basalt> that from tuff> that from granite.The titratable acidity and titratable alkalinity ware closely related with origination of the variable charges of red soils,and to a certain extent were responsible for variable negative and positive charges of the soils.

  11. Process for treating alkaline wastes for vitrification

    Science.gov (United States)

    Hsu, Chia-lin W.

    1994-01-01

    According to its major aspects and broadly stated, the present invention is a process for treating alkaline waste materials, including high level radioactive wastes, for vitrification. The process involves adjusting the pH of the wastes with nitric acid, adding formic acid (or a process stream containing formic acid) to reduce mercury compounds to elemental mercury and MnO{sub 2} to the Mn(II) ion, and mixing with class formers to produce a melter feed. The process minimizes production of hydrogen due to noble metal-catalyzed formic acid decomposition during, treatment, while producing a redox-balanced feed for effective melter operation and a quality glass product. An important feature of the present invention is the use of different acidifying and reducing, agents to treat the wastes. The nitric acid acidifies the wastes to improve yield stress and supplies acid for various reactions; then the formic acid reduces mercury compounds to elemental mercury and MnO{sub 2}) to the Mn(II) ion. When the pH of the waste is lower, reduction of mercury compounds and MnO{sub 2}) is faster and less formic acid is needed, and the production of hydrogen caused by catalytically-active noble metals is decreased.

  12. 2nd Generation alkaline electrolysis. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Yde, L. [Aarhus Univ. Business and Social Science - Centre for Energy Technologies (CET), Aarhus (Denmark); Kjartansdottir, C.K. [Technical Univ. of Denmark. DTU Mechanical Engineering, Kgs. Lyngby (Denmark); Allebrod, F. [Technical Univ. of Denmark. DTU Energy Conversion, DTU Risoe Campus, Roskilde (Denmark)] [and others

    2013-03-15

    The overall purpose of this project has been to contribute to this load management by developing a 2{sup nd} generation of alkaline electrolysis system characterized by being compact, reliable, inexpensive and energy efficient. The specific targets for the project have been to: 1) Increase cell efficiency to more than 88% (according to the higher heating value (HHV)) at a current density of 200 mA /cm{sup 2}; 2) Increase operation temperature to more than 100 degree Celsius to make the cooling energy more valuable; 3) Obtain an operation pressure more than 30 bar hereby minimizing the need for further compression of hydrogen for storage; 4) Improve stack architecture decreasing the price of the stack with at least 50%; 5) Develop a modular design making it easy to customize plants in the size from 20 to 200 kW; 6) Demonstrating a 20 kW 2{sup nd} generation stack in H2College at the campus of Arhus University in Herning. The project has included research and development on three different technology tracks of electrodes; an electrochemical plating, an atmospheric plasma spray (APS) and finally a high temperature and pressure (HTP) track with operating temperature around 250 deg. C and pressure around 40 bar. The results show that all three electrode tracks have reached high energy efficiencies. In the electrochemical plating track a stack efficiency of 86.5% at a current density of 177mA/cm{sup 2} and a temperature of 74.4 deg. C has been shown. The APS track showed cell efficiencies of 97%, however, coatings for the anode side still need to be developed. The HTP cell has reached 100 % electric efficiency operating at 1.5 V (the thermoneutral voltage) with a current density of 1. 1 A/cm{sup 2}. This track only tested small cells in an externally heated laboratory set-up, and thus the thermal loss to surroundings cannot be given. The goal set for the 2{sup nd} generation electrolyser system, has been to generate 30 bar pressure in the cell stack. An obstacle to be

  13. Response of Desulfovibrio vulgaris to Alkaline Stress

    Energy Technology Data Exchange (ETDEWEB)

    Stolyar, S.; He, Q.; He, Z.; Yang, Z.; Borglin, S.E.; Joyner, D.; Huang, K.; Alm, E.; Hazen, T.C.; Zhou, J.; Wall, J.D.; Arkin, A.P.; Stahl, D.A.

    2007-11-30

    The response of exponentially growing Desulfovibrio vulgarisHildenborough to pH 10 stress was studied using oligonucleotidemicroarrays and a study set of mutants with genes suggested by microarraydata to be involved in the alkaline stress response deleted. The datashowed that the response of D. vulgaris to increased pH is generallysimilar to that of Escherichia coli but is apparently controlled byunique regulatory circuits since the alternative sigma factors (sigma Sand sigma E) contributing to this stress response in E. coli appear to beabsent in D. vulgaris. Genes previously reported to be up-regulated in E.coli were up-regulated in D. vulgaris; these genes included three ATPasegenes and a tryptophan synthase gene. Transcription of chaperone andprotease genes (encoding ATP-dependent Clp and La proteases and DnaK) wasalso elevated in D. vulgaris. As in E. coli, genes involved in flagellumsynthesis were down-regulated. The transcriptional data also identifiedregulators, distinct from sigma S and sigma E, that are likely part of aD. vulgaris Hildenborough-specific stress response system.Characterization of a study set of mutants with genes implicated inalkaline stress response deleted confirmed that there was protectiveinvolvement of the sodium/proton antiporter NhaC-2, tryptophanase A, andtwo putative regulators/histidine kinases (DVU0331 andDVU2580).

  14. High temperature and pressure alkaline electrolysis

    DEFF Research Database (Denmark)

    Allebrod, Frank; Chatzichristodoulou, Christodoulos; Mogensen, Mogens Bjerg

    2013-01-01

    and pressures. Two measurement systems were built to perform measurements under high pressures and at elevated temperatures of up to 95 bar and 250 °C, respectively. The conductivity of aqueous KOH and aqueous KOH immobilized in a porous SrTiO3 structure were investigated at elevated temperatures and high...... the operational temperature and pressure to produce pressurized hydrogen at high rate (m3 H2·h-1·m-2 cell area) and high electrical efficiency. This work describes an exploratory technical study of the possibility to produce hydrogen and oxygen with a new type of alkaline electrolysis cell at high temperatures...... concentrations of the electrolyte using the van der Pauw method in combination with electrochemical impedance spectroscopy (EIS). Conductivity values as high as 2.9 S cm-1 for 45 wt% KOH aqueous KOH and 0.84 S cm-1 for the immobilized KOH of the same concentration were measured at 200 °C. Porous SrTiO3 was used...

  15. Origins of Calc-Alkaline (s.l.) Andesitic Magmas - Where We Stand Today

    Science.gov (United States)

    Sisson, T. W.

    2015-12-01

    The mainly igneous continents have intermediate mean SiO2 (~60 wt%) and Mg# (0.4-0.55 mol). Bowen championed crystallization-differentiation of basalts to silicic daughter liquids, but he encountered difficulties with conflicting evidence for iron enrichment. We now know that as dry reduced basalts crystallize, melt SiO2 begins climbing steeply at F (melt fraction): 0.25-0.35, reaching intermediate values at F: 0.1-0.2. H2O changes basalt crystallization by (1) increasing the ratio of olivine to high-Ca pyroxene, (2) delaying onset and reducing the proportion of plagioclase, (3) stabilizing calcic plagioclase, (4) destabilizing low-Ca pyroxene, (5) eventually stabilizing amphibole, and (6) destabilizing silicate minerals more than magnetite. Factors 1-5 enrich melts early in SiO2, 6 limits decline of Mg#. H2O of 2-6 wt% is sufficient for early SiO2 enrichment; fO2 modestly above Ni-NiO yields daughter liquids with high (calc-alkaline) Mg#s. These values are matched by many natural subduction zone magmas, so seemingly, the problem is solved. Yet, difficulties remain: Melt SiO2 enrichment commences at F: 0.6-0.7 in experiments on hydrous Mg basalts, reaching intermediate SiO2 at F: 0.2-0.4. Cumulates 60-80% of the basalt mass must have returned to the mantle if basalt differentiation formed the continents. Differentiation mainly near the base of the crust has geologic support, and would aid disposal of cumulates, but most experiments on hydrous basalts at such pressures yield peraluminous andesitic liquids, unlike common metaluminous andesites. A composite scenario avoiding peraluminous intermediates is crystallization-differentiation plus mixing with silicic liquids mainly residual or remelted from shortly antecedent intrusions. Even in this case, cumulates and restites exceeding the continental mass must have been lost. The Archean was different: Residual-eclogite-sourced granitoids are widespread, but experiments on hydrous eclogites at plausible temperatures

  16. Optimization of Soilless Media for Alkaline Irrigation Water

    OpenAIRE

    Tramp, Cody Alexander; Chard, Julie K.; Bugbee, Bruce

    2009-01-01

    High root zone pH reduces nutrient availability and high alkalinity water is strongly buffered around an alkaline pH. Soilless media can be altered to improve nutrient availability. This study was conducted to optimize the composition of soilless media for use with high alkalinity water. Mixes of peat and/or perlite or vermiculite in 50/50 and 33/33/33 volumetric ratios were tested. In some studies, mixes were also amended with up to 2.4 g/L of dolomite limestone to neutralize the initial aci...

  17. Onset of Grain Boundary Migration and Drastic Weakening of Quartzite during increasing grade of Metamorphism in the Contact Aureole surrounding the Eureka Valley-Joshua Flat-Beer Creek pluton, California, USA

    Science.gov (United States)

    Morgan, S. S.; Student, J. J.; Jakeway, J.

    2015-12-01

    The Eureka Valley-Joshua Flat-Beer Creek (EJB) pluton in eastern California is surrounded by a ~1.3 km wide intensely deformed concordant aureole of metasedimentary rocks. South of the pluton, the Harkless Quartzite can be mapped from where it is located outside the aureole, with its regional strike through the transition into the aureole and concordancy with the pluton. The transition into concordancy, which is fairly abrupt, occurs over a distance of less than 100 m. Across this transition the bedding rotates close to 90° to become subvertical. Here the metasedimentary formations in the aureole have undergone 65% shortening. A suite of Harkless Quartzite samples was collected starting at 2.3 km south of the pluton, across the transition into concordancy at 1.3 km, and to within 450m from the pluton contact. Microstructurally, the transition is defined by changes in the dominant recrystallization mechanisms. At 2.3 km from the pluton, subgrain rotation recrystallization (SGR) plus grain boundary migration (GBM) operate together and many sedimentary grains (rounded grain boundaries) exist. As the pluton is approached, SGR decreases, GBM increases, and rounded grain boundaries slowly disappear. The abrupt transition into concordancy is marked by the final disappearance of SGR and rounded grain boundaries and extensive GBM. The transition is not completely smooth, and other variables such as pinning and amount of fluid inclusions seem to have a strong local affect on the dominant recrystallization mechanism. We suspect that the onset of extensive GBM allows for the diffusion of water into the crystal lattice which results in the drastic weakening and rotation of metasedimentary formations into concordancy.

  18. Does numerical modelling of apparent partial loss Ar/Ar age spectra of hornblende give the correct thermal history of terranes? Insights from the Palaeoproterozoic Lapland-Kola orogen (Russia)

    Science.gov (United States)

    de Jong, K.

    2012-04-01

    We investigate the validity of numerical modelling of hornblende 40Ar/39Ar age spectra obtained from the same sample by step-heating with: 1) a defocused laser on 1.5 mm diameter discs micro-sampled from polished petrographic thin sections with a microscope-mounted drill, and 2) a resistance-heated furnace using handpicked mineral separate. Micro-sampling enables to obtain parts of mineral grains without zoning or included phases from targeted sites. Three samples were analysed: a tonalitic gneiss and a biotite-bearing amphibolite, from the same outcrop-1, and a biotite-free amphibolite from neighbouring outcrop-2. The material is from the Neoarchaean Murmansk terrane in the Palaeoproterozoic Lapland-Kola collisional belt along the northern margin of the Fennoscandian (Baltic) Shield. Hornblendes from the biotite-bearing gneiss and amphibolite (outcrop-1) yielded 40Ar/39Ar age spectra with progressively increasing step ages, whereas the biotite-free amphibole (outcrop-2) gave flat age spectra for both drilled disc and separate. These so-called staircase-type age spectra have been classically interpreted by partial loss of radiogenic argon by diffusion processes during younger thermal reworking. We applied numerical modelling tools (Double-Pulse, MacArgon) based on diffusion theory and that assume thermally activated loss of radiogenic Ar from so-called lower retentive lattice sites by solid-state volume diffusion. Modelling results suggest that staircase-shaped age spectra of our Neoarchaean hornblende are due to argon losses of 40-50% during reheating to 450 ± 25° C in Palaeoproterozoic time, and that flat spectra imply a thermally undisturbed Neoarchaean isotope system. These results would imply that neighbouring samples would have experienced sharply contrasting thermal histories. Hornblende with apparent partial loss age spectra is exclusively obtained from samples in which

  19. Assessment of gamma radiation exposure and distribution of natural radioactivity in beach sands associated with plutonic rocks of Greece

    Science.gov (United States)

    Papadopoulos, Argyrios; Koroneos, Antonios; Christofides, Georgios; Stoulos, Stylianos

    2016-04-01

    This study aims to evaluate the activity concentrations of 238U, 226Ra, 232Th, 228Th and 40K along beaches of Greece associated with plutonic rocks. They range from 6-940, 1-2292, 5-10143, 5-9953 and 27-1319 Bq/kg respectively, with some of them representing the highest values of natural radioactivity measured in sediments in Greece. The investigated beaches include Sithonia peninsula (Chalkidiki, N. Greece), some islands of the Aegean Sea (Mykonos, Paros, Naxos, Serifos, Ikaria), the area of Kavala (N. Greece), Samothraki island, NE Chalkidiki and Maronia (NE Greece). Several of these places are associated with high touristic activity such as Mykonos, Naxos, Paros, Serifos, Ikaria, Sithonia and Kavala. The (% wt.) heavy magnetic fraction (HM) (allanite, amphibole, mica, clinopyroxene, magnetite and hematite), the heavy non-magnetic fraction (HNM) (monazite, zircon, titanite and apatite) and the total heavy fraction (TH), were correlated with the concentrations of the measured radionuclides in the bulk samples. The heavy fractions seem to control the activity concentrations of 238U and 232Th of all the samples, showing some local differences in the main 238U and 232Th mineral carrier. The measured radionuclides in the beach sands were normalized to the respective values measured in the granitic rocks, which are their most probable parental rocks, so as to provide data upon their enrichment or depletion. The highest values of the equivalent dose have been reported in Mykonos, Naxos, Kavala and Sithonia. The annual equivalent dose which should be limited to at least 1 mSv y-1, varies between 0.003 and 0.759 mSv y-1 for tourists and from 0.012 to 3.164 mSv y-1 for local people working on the beach.

  20. Petrology, Magnetic susceptibility, Tectonic setting and mineralization associated with Plutonic and Volcanic Rocks, Eastern Bajestan and Taherabad, Iran

    Directory of Open Access Journals (Sweden)

    Malihe Ghoorchi

    2009-09-01

    Full Text Available Study area is located in district of Bajestan and Ferdows cities, NE of Iran. Structurally, this area is part of Lut block. The oldest exposed rocks, to the north of intrusive rocks and in Eastern Bajestan, are meta-chert, slate, quartzite, thin-bedded crystalline limestone and meta-argillite. The sedimentary units are: Sardar Formation (Carboniferous, Jamal Formation (Permian, Sorkh Shale and Shotori Formations (Triassic, carbonateous rocks (Cretaceous and lithostratigraphically equivalent to Kerman conglomerate (Cretaceous-Paleocene are exposed in this area. Based on relative age, magmatism in eastern Bajestan and Taherabad started after Late Cretaceous and it has been active and repeated during Tertiary time. At least, three episodes of volcanic activities are recognized in this area. The first stage was mainly volcanic flow with mafic composition and minor intermediate. The second episode was mainly intermediate in composition. The third stage was changed to acid-intermediate in composition. Since the plutonic rocks intruded the volcanic rocks, therefore they may be Oligo-Miocene age. Bajestan intrusive rocks are granite-granodiorite-quartz monzonite. Taherabad intrusive rocks are diorite-quartz diorite- monzonite-latite. Bajestan intrusive rocks are reduced type (ilmenite series and Taherabad intrusive rocks are oxidized type (magnetite series.Based on geochemical analysis including trace elements, REE and isotopic data, Bajestan intrusive rocks formed in continental collision zone and the magma has crustal origin. Taherabad intrusive rocks were formed in subduction zone and magma originated from oceanic crust. Taherabad intrusive rock has exploration potential for Cu-Au and pb.

  1. Sulfate—Exchange Alkalinity of Ferralsol Colloid

    Institute of Scientific and Technical Information of China (English)

    ZHANGGANGYA; ZHANGXIAONIAN

    1999-01-01

    The amount of OH- replaced by sulfate,i.e.,sulfate-exchange alkalinity,from the electric double layer of ferralsol colloid was measured quantitatively in different conditions with an automatic titration equipment.The amount of OH- release increased with the amount of Na2SO4 added and decreased with raising pH in the suspension of ferralsol colloid.The exchange acidity was displayed as pH was higher than 5.6,If the negative effect of sodium ions was offset,the amount of OH- replaced by sulfate was larger than the original amount of OH- released in the pH range of lower than 5.8.The amount of OH- released decreased rapidly as pH was higher than 6.0 and dropped to zero when pH reached 6.5.In the solution of 2.0molL-1 NaClO4,the amount of OH- repleaced by sulfate from the surface of ferralsol colloid could be considered as the amount of OH- adsorbed by ligand exchange reaction.The amount of OH- released in the solution of NaClO4 concentration below 2.0mol L-1 from which the amount of OH- adsorbed by ligand exchange reaction was subtracted could be conidered as the OH- adsorbed by electrostatic force,The OH- adsorbed by electrostatic force decreased with increases in the concentration of NaClO4 and pH and increased almost linearly with the increasing amount of Na2SON4 added.The percentages of OH- adsorbed by electrostatic force in water and in the electrolyte solutions of 0.05 and 0.5mol L-1 NaClO4 in the total OH- released were calculated,respectively.

  2. Chlorine solubility in evolved alkaline magmas

    Directory of Open Access Journals (Sweden)

    M. R. Carroll

    2005-06-01

    Full Text Available Experimental studies of Cl solubility in trachytic to phonolitic melts provide insights into the capacity of alkaline magmas to transport Cl from depth to the earth?s surface and atmosphere, and information on Cl solubility variations with pressure, temperature and melt or fluid composition is crucial for understanding the reasons for variations in Cl emissions at active volcanoes. This paper provides a brief review of Cl solubility experiments conducted on a range of trachytic to phonolitic melt compositions. Depending on the experimental conditions the melts studied were in equilibrium with either a Cl-bearing aqueous fluid or a subcritical assemblage of low- Cl aqueous fluid + Cl-rich brine. The nature of the fluid phase(s was identified by examination of fluid inclusions present in run product glasses and the fluid bulk composition was calculated by mass balance. Chlorine concentrations in the glass increase with increasing Cl molality in the fluid phase until a plateau in Cl concentration is reached when melt coexists with aqueous fluid + brine. With fluids of similar Cl molality, higher Cl concentrations are observed in peralkaline phonolitic melts compared with peraluminous phonolitic melts; overall the Cl concentrations observed in phonolitic and trachytic melts are approximately twice those found in calcalkaline rhyolitic melts under similar conditions. The observed negative pressure dependence of Cl solubility implies that Cl contents of melts may actually increase during magma decompression if the magma coexists with aqueous fluid and Cl-rich brine (assuming melt-vapor equilibrium is maintained. The high Cl contents (approaching 1 wt% Cl observed in some melts/glasses from the Vesuvius and Campi Flegrei areas suggest saturation with a Cl-rich brine prior to eruption.

  3. Photovoltaic hydrogen production with commercial alkaline electrolysers

    Energy Technology Data Exchange (ETDEWEB)

    Ursua, A.; Lopez, J.; Gubia, E.; Marroyo, L.; Sanchis, P. [Public Univ. of Navarra, Pamplona (Spain). Dept. of Electric and Electronic Engineering

    2010-07-01

    Renewable energy sources and Electrolysis generate the so-called green Hydrogen, a zero-emission and potentially fossil fuel independent energy source. However, the inherent variability of the renewable energy sources implies a mode of operation for which most current electrolysers have not been designed. This paper analyses the operation of a water electrolyser fed with photovoltaic (PV) generator electric profile. The system, Integrated by a 1 Nm{sup 3}/h Hydrogenics alkaline electrolyser and a 5100 W PV generator with 60 BP585 modules, is installed at the Public University of Navarra (Spain). The PV generator profile fed to the electrolyser is emulated by a custom-made apparatus designed and built by the authors of this paper. The profile is designed according to real irradiance data measured by a calibration cell. The irradiance data are converted to the electric power profile that the PV generator would have delivered in case of having been connected to the electrolyser by means of a DC/DC converter with maximum power point tracking (MPPT). Finally, from previously measured power-current electrolyser characteristic curves, the current profile to be delivered to the electrolyser is obtained and programmed to the electronic device. The electrolyser was tested for two types of days. During the first day, the irradiance was very stable, whereas during the second day, the irradiance was very variable. The experimental results show an average power consumption rate and an efficiency of 4908 Wh/Nm{sup 3} and 72.1%, on the first day, and 4842 Wh/Nm{sup 3} and 73.3% on the second day. The electrolyser performance was particularly good in spite of the high variability of the electric supply of the second day. (orig.)

  4. Marked Transient Alkaline Phosphatemia Following Pediatric Liver Transplantation

    Science.gov (United States)

    Koneru, Baburao; Carone, Eduardo; Malatack, J. Jeffrey; Esquivel, Carlos O.; Starzl, Thomas E.

    2010-01-01

    An isolated marked transient rise in serum alkaline phosphatase levels in otherwise healthy children is a well-documented occurrence. However, in children undergoing liver transplantation, elevated alkaline phosphatase values raise the possibility of biliary obstruction, rejection, or both. During a 6-year period, 6 of 278 children undergoing liver transplantation exhibited a similar phenomenon as an isolated abnormality. None had rejection, biliary obstruction, or other allograft dysfunction during a long follow-up. Eventually and without intervention, the alkaline phosphatase levels returned to normal. These instructive cases suggest that caution be used in advocating Invasive procedures if elevated alkaline phosphatase levels are an isolated abnormality, and close observation with noninvasive testing is recommended. PMID:2658549

  5. Cation exchange properties of zeolites in hyper alkaline aqueous media.

    Science.gov (United States)

    Van Tendeloo, Leen; de Blochouse, Benny; Dom, Dirk; Vancluysen, Jacqueline; Snellings, Ruben; Martens, Johan A; Kirschhock, Christine E A; Maes, André; Breynaert, Eric

    2015-02-03

    Construction of multibarrier concrete based waste disposal sites and management of alkaline mine drainage water requires cation exchangers combining excellent sorption properties with a high stability and predictable performance in hyper alkaline media. Though highly selective organic cation exchange resins have been developed for most pollutants, they can serve as a growth medium for bacterial proliferation, impairing their long-term stability and introducing unpredictable parameters into the evolution of the system. Zeolites represent a family of inorganic cation exchangers, which naturally occur in hyper alkaline conditions and cannot serve as an electron donor or carbon source for microbial proliferation. Despite their successful application as industrial cation exchangers under near neutral conditions, their performance in hyper alkaline, saline water remains highly undocumented. Using Cs(+) as a benchmark element, this study aims to assess the long-term cation exchange performance of zeolites in concrete derived aqueous solutions. Comparison of their exchange properties in alkaline media with data obtained in near neutral solutions demonstrated that the cation exchange selectivity remains unaffected by the increased hydroxyl concentration; the cation exchange capacity did however show an unexpected increase in hyper alkaline media.

  6. Age and isotopic fingerprints of some plutonic rocks in the Wiborg rapakivi granite batholith with special reference to the dark wiborgite of the Ristisaari Island

    Directory of Open Access Journals (Sweden)

    Rämö, O.T.

    2014-12-01

    Full Text Available The mid-Proterozoic, locus classicus Wiborg rapakivi granite batholith of southeastern Finland and adjacent Russia comprises a varying, bimodal (silicic-basic sequence of plutonic, subvolcanic, and volcanic rocks. At the current level of erosion silicic rocks are dominant, the most prominent of which are wiborgites and dark wiborgites (that have been considered to mark the main build-up stage of the batholith and pyterlites. New observations and optical microscopy data from the dark wiborgite-dominated Ristisaari Island in the southern, off-shore part of the Wiborg batholith show that dark plagioclase megacrysts in dark wiborgite are calcic xenocrysts. They were probably incorporated into wiborgite magma from consanguineous massiftype anorthosite magmas in the course of the evolution of the bimodal magmatic system. Our new ID-TIMS U-Pb zircon age of the Ristisaari Island dark wiborgite, 1627±3 Ma, is the youngest isotopic age so far determined for the plutonic rocks of the Wiborg batholith. This, combined with preexisting U-Pb zircon data, implies a minimum duration of 12 m.y. (1642–1630 Ma for the emplacement of the plutonic rocks of the batholith. Combined with data on highlevel dike rocks, a window of at least 20 m.y. (1642–1622 Ma is implied. Furthermore, as the batholith grew, the overall locus of magmatism may have shifted southwards. New whole-rock Nd isotope data on the dark wiborgite of the Ristisaari Island and three further granites of the batholith, as well as Nd (whole-rock and Sr (whole-rock, plagioclase isotope data on a spectrolite massif-type anorthosite from the east-central part of the batholith, are also presented. These data suggest that the lithosphere across the Wiborg batholith area in the southeastern part of the Svecofennian orogen may vary slightly in overall mantle separation age.

  7. Early Cretaceous U-Pb zircon ages for the Copiapó plutonic complex and implications for the IOCG mineralization at Candelaria, Atacama Region, Chile

    Science.gov (United States)

    Marschik, Robert; Söllner, Frank

    2006-12-01

    Four of the major plutons in the vicinity of the Candelaria mine (470 Mt at 0.95% Cu, 0.22 g/t Au, 3.1 g/t Ag) and a dike-sill system exposed in the Candelaria open pit have been dated with the U-Pb zircon method. The new geochronological data indicate that dacite magmatism around 123 Ma preceded the crystallization of hornblende diorite (Khd) at 118 ± 1 Ma, quartz-monzonite porphyry (Kqm) at 116.3 ± 0.4 Ma, monzodiorite (Kmd) at 115.5 ± 0.4 Ma, and tonalite (Kt) at 110.7 ± 0.4 Ma. The new ages of the plutons are consistent with field relationships regarding the relative timing of emplacement. Plutonism temporally overlaps with the iron oxide Cu-Au mineralization (Re-Os molybdenite ages at ˜115 Ma) and silicate alteration (ages mainly from 114 to 116 and 110 to 112 Ma) in the Candelaria-Punta del Cobre district. The dated dacite porphyry and hornblende diorite intrusions preceded the ore formation. A genetic link of the metallic mineralization with the quartz-monzonite porphyry and/or the monzodiorite is likely. Both of these metaluminous, shoshonitic (high-K) intrusions could have provided energy and contributed fluids, metals, and sulfur to the hydrothermal system that caused the iron oxide Cu-Au mineralization. The age of the tonalite at 110.7 Ma falls in the same range as the late alteration at 110 to 112 Ma. Tonalite emplacement may have sustained existing or driven newly developed hydrothermal cells that caused this late alteration or modified 40Ar/39Ar and K/Ar systematic in some areas.

  8. Complex trace element effects of source mixing-fractional crystallization composite processes in Kalaan granodiorite pluton along Wulungu tectonic belt,northern Xinjiang

    Institute of Scientific and Technical Information of China (English)

    刘伟; A.Masuda

    1995-01-01

    Mixing-fractional crystallization composite processes generate 6 complex patterns,which aresynthesized into 3 models,on C21/C31-C11/C31 ratio correlation plots of trace eleroents E1,E2,E3 according totheir relative incompatibility.Three of the six effects are clearly displayed on ratio-ratio correlation plots oftrace elements in the Kalaan granodiorite pluton,indicative of a source mixing-fractional crystallization compositeprocess.The overlying lithospheric mantle was modified by the subduction of oceanic plate during Palaeozoic.The incompatibility order of the 7 concerned trace elements is DTa

  9. Emplacement age for the mafic-ultramafic plutons in the northern Dabie Mts. (Hubei): Zircon U-Pb, Sm-Nd and 40Ar/39Ar dating

    Institute of Scientific and Technical Information of China (English)

    WANG; Jianghai

    2002-01-01

    , China, Sci. in China, Ser. D, 2000, 43(2): 225-236.[11]Hacker, B. R., Wang, Q. C., Ar/Ar geochronology of ultrahigh-pressure metamorphism in Central China, Tectonics, 1995, 14: 994-1006.[12]Ge, N. J., Hou, Z. H., Li, H. M. et al., Zircon U-Pb ages of the Shacun gabbro body, Yuexi, Dabie orogen and its geological implications, Chinese Sci. Bull., 2000, 45(1): 74-79.[13]Xu, S. T., Liu, Y. C., Jiang, L. L. et al., Tectonic Regime and Evolution of the Dabie Mountains, Beijing: Science Press, 1994, 1-175.[14]Li, S. G., Ni, Y. H., Zheng, S. G. et al., Interaction between subducted continental crust and the mantle: I. Major and trace element geochemistry of syncollisional mafic-ultramafic intrusions in the Dabie Mountains, Sci. in China, Ser. D, 1998, 41(5): 545-553.[15]Blundy, J. D., Holland, T. J. B., Calcic amphibole equilibrium and a new amphibole plagioclase geothermometer, Contrib. Mineral. Petrol. 1990, 104: 208-224.[16]Hammartron, J. M., Zen, E. A., Aluminum in hornbole: an empirical igneous geobarometer, Amer. Mineral., 1986, 71: 1297-1313.[17]Hollister, L. S., Grisson, G. C., Peters, E. K. et al., Confirmation of the empirical correlation of Al in hornblende with pressure of solidification of calcalkaline plutons, Amer. Mineral., 1987, 72: 231-239.[18]Johnson, M. C., Rutherford, M. J., Experimental calibration of an aluminium-hornblende geobarometer applicable to calc-alkaline rocks, EOS, 1988, 69: 1511.[19]Whitney, J. A., Stormer, J. C., The distribution of NaAlSi3O8 between coexisting microcline and plagioclase and its effect on geothermometric calculations, Am. Mineral., 1977, 62: 687-691.[20]Zhang, R. Y., Cong, B. L., Mineral Thermometers and Barometers, Beijing: Geological Publishing House, 1983, 150-173.[21]Krogh, T. E., A low-contamination method for hydrothermal decomposition of zircon and extraction of U and Pb for isotopic age determinations, Geochim. Cosmochim. Acta, 1973, 48: 505-511.[22]Krogh, T. E., Vapour

  10. Crystallization and eruption ages of Breccia Museo (Campi Flegrei caldera, Italy) plutonic clasts and their relation to the Campanian ignimbrite

    Science.gov (United States)

    Gebauer, Samantha K.; Schmitt, Axel K.; Pappalardo, Lucia; Stockli, Daniel F.; Lovera, Oscar M.

    2014-01-01

    The Campi Flegrei volcanic district (Naples region, Italy) is a 12-km-wide, restless caldera system that has erupted at least six voluminous ignimbrites during the late Pleistocene, including the >300 km3 Campanian ignimbrite (CI) which originated from the largest known volcanic event of the Mediterranean region. The Breccia Museo (BM), a petrologically heterogeneous and stratigraphically complex volcanic deposit extending over 200 km2 in close proximity to Campi Flegrei, has long remained contentious regarding its age and stratigraphic relation to the CI. Here, we present crystallization and eruption ages for BM plutonic ejecta clasts that were determined via uranium decay series and (U-Th)/He dating of zircon, respectively. Despite mineralogical and textural heterogeneity of these syenitic clasts, their U-Th zircon rim crystallization ages are indistinguishable with an average age of 49.7 ± 2.5 ka (2σ errors; mean square of weighted deviates MSWD = 1.2; n = 34). A subset of these crystals was used to obtain disequilibrium-corrected (U-Th)/He zircon ages which average 41.7 ± 1.8 ka (probability of fit P = 0.54; n = 15). This age closely overlaps with published CI 40Ar/39Ar eruption ages (40.6 ± 0.1 ka) after recalibration to recently revised flux monitor ages. Concordant eruption ages for BM and CI agree with previous chemostratigraphic and paleomagnetic correlations, suggesting their origin from the same eruption. However, they are at variance with recalibrated 40Ar/39Ar ages which have BM postdate CI by 3 ± 1 ka. BM syenites show similar geochemical and Sr-Nd isotopical features of pre-caldera rocks erupted between 58 and 46 ka, but are distinctive from subsequent caldera-forming magmas. Energy-constrained assimilation and fractional crystallization modeling of Nd-Sr isotopic data suggests that pre-caldera magmas formed a carapace of BM-type intrusions in a mid-crust magma chamber (≥8 km depth) shielding the younger CI magma from contamination by

  11. The Quantitative Study of Pluton Selection for the Disposal Repository of High Level Waste in Beishan%高放废物处置库北山预选区岩体筛选定量研究

    Institute of Scientific and Technical Information of China (English)

    钟霞; 王驹; 黄树桃; 王树红

    2012-01-01

    以北山预选岩体的地学数据集成为基础、GIS技术为支撑,开展预选区众多岩体筛选特征分析,针对预选区岩体规模、形态与完整性开展定性及定量研究,为北山预选区岩体筛选和评价提供方法与依据.%Based on the geoscience data integration and the support of the GIS, the paper analysised the characteristic of the pluton and quantificationally studied their scale and shape and integrality. The research not only provides the new ways to the assessement of the pluton but also the crieteria for the screening of candidate plutons for the disposal repositary.

  12. Evaluation of some bean lines tolerance to alkaline soil

    Directory of Open Access Journals (Sweden)

    Abeer A. Radi

    2012-01-01

    Full Text Available Introduction: In less arid climates, salts are less concentrated and sodium dominates in carbonate and bicarbonate forms, which enhance the formation of alkaline soils. The development and identification of salt-tolerant crop cultivars or lines would complement salt management programs to improve the productivity and yields of salt stressed plants.Materials and methods: This work was to study the evaluation of alkalinity tolerance of some bean lines grown under different levels of sodium carbonate (Na2CO3 to select the most alkalinity tolerant lines versus the most-sensitive ones out of 6 lines of the test plants.Results: The symptoms induced by alkalinity included reduction in root, shoot growth, and leaf area which were more severe in some bean lines. Potassium leakage was severely affected by alkalinity in some lines at all tested levels, while in some others a moderate damage was manifested only at the higher levels. The increase in Na2CO3 level was associated with a gradual fall in chlorophyll a and b biosynthesis of all the test bean lines. However, alkalinity at low and moderate levels had a favorable effect on the biosynthesis of carotenoids in all the test bean lines. The increase in Na2CO3 supply had a considerable stimulatory effect on sodium accumulation, while potassium accumulation fluctuated in organs of bean lines.Conclusion: Assiut 1104 out of all the different lines investigated was found to display the lowest sensitivity to alkalinity stress, while Assiut 12/104 was the most sensitive one.

  13. Alkalinity Enrichment Enhances Net Calcification of a Coral Reef Flat

    Science.gov (United States)

    Albright, R.; Caldeira, K.

    2015-12-01

    Ocean acidification is projected to shift reefs from a state of net accretion to one of net dissolution sometime this century. While retrospective studies show large-scale changes in coral calcification over the last several decades, it is not possible to unequivocally link these results to ocean acidification due to confounding factors of temperature and other environmental parameters. Here, we quantified the calcification response of a coral reef flat to alkalinity enrichment to test whether reef calcification increases when ocean chemistry is restored to near pre-industrial conditions. We used sodium hydroxide (NaOH) to increase the total alkalinity of seawater flowing over a reef flat, with the aim of increasing carbonate ion concentrations [CO32-] and the aragonite saturation state (Ωarag) to values that would have been attained under pre-industrial atmospheric pCO2 levels. We developed a dual tracer regression method to estimate alkalinity uptake (i.e., calcification) in response to alkalinity enrichment. This approach uses the change in ratios between a non-conservative tracer (alkalinity) and a conservative tracer (a non-reactive dye, Rhodamine WT) to assess the fraction of added alkalinity that is taken up by the reef as a result of an induced increase in calcification rate. Using this method, we estimate that an average of 17.3% ± 2.3% of the added alkalinity was taken up by the reef community. In providing results from the first seawater chemistry manipulation experiment performed on a natural coral reef community (without artificial confinement), we demonstrate that, upon increase of [CO32-] and Ωarag to near pre-industrial values, reef calcification increases. Thus, we conclude that, the impacts of ocean acidification are already being felt by coral reefs. This work is the culmination of years of work in the Caldeira lab at the Carnegie Institution for Science, involving many people including Jack Silverman, Kenny Schneider, and Jana Maclaren.

  14. CHARACTERIZATION OF BULK SOIL HUMIN AND ITS ALKALINE-SOLUBLE AND ALKALINE-INSOLUBLE FRACTIONS

    Directory of Open Access Journals (Sweden)

    Cuilan Li

    2015-02-01

    Full Text Available Humic substances are the major components of soil organic matter. Among the three humic substance components (humic acid, fulvic acid, and humin, humin is the most insoluble in aqueous solution at any pH value and, in turn, the least understood. Humin has poor solubility mainly because it is tightly bonded to inorganic soil colloids. By breaking the linkage between humin and inorganic soil colloids using inorganic or organic solvents, bulk humin can be partially soluble in alkali, enabling a better understanding of the structure and properties of humin. However, the structural relationship between bulk humin and its alkaline-soluble (AS and alkaline-insoluble (AIS fractions is still unknown. In this study, we isolated bulk humin from two soils of Northeast China by exhaustive extraction (25 to 28 times with 0.1 mol L-1 NaOH + 0.1 mol L-1 Na4P2O7, followed by the traditional treatment with 10 % HF-HCl. The isolated bulk humin was then fractionated into AS-humin and AIS-humin by exhaustive extraction (12 to 15 times with 0.1 mol L-1 NaOH. Elemental analysis and solid-state 13C cross-polarization magic angle spinning nuclear magnetic resonance (13C CPMAS NMR spectroscopy were used to characterize and compare the chemical structures of bulk humin and its corresponding fractions. The results showed that, regardless of soil types, bulk humin was the most aliphatic and most hydrophobic, AS-humin was the least aliphatic, and AIS-humin was the least alkylated among the three humic components. The results showed that bulk humin and its corresponding AS-humin and AIS-humin fractions are structurally differed from one another, implying that the functions of these humic components in the soil environment differed.

  15. Petrogenesis and tectonic setting of the early Mesozoic Xitian granitic pluton in the middle Qin-Hang Belt, South China: Constraints from zircon U-Pb ages and bulk-rock trace element and Sr-Nd-Pb isotopic compositions

    Science.gov (United States)

    Wu, Qianhong; Cao, Jingya; Kong, Hua; Shao, Yongjun; Li, Huan; Xi, Xiaoshuang; Deng, Xuantong

    2016-10-01

    The Xitian pluton in southeast Hunan province is one of the early Mesozoic (Indosinian) granitic plutons in the South China Block. It is composed of biotite adamellite with K-feldspar megacrysts, biotite adamellite, and biotite granite that have U-Pb zircon ages of 229.9 ± 1.4 Ma, 223.6 ± 1.3 Ma, and 224.0 ± 1.4 Ma, respectively. The Indosinian granitoids in the Xitian pluton belong to S-type granites, with highly radiogenic initial 87Sr/86Sr ratios (0.71397-0.71910), negative εNd(t) values ranging from -10.1 to -9.4, and old Nd model ages (1858-1764 Ma). They are enriched in radiogenic Pb isotopes, with (206Pb/204Pb)t ranging from 18.130 to 18.903, (207Pb/204Pb)t from 15.652 to 15.722, and (208Pb/204Pb)t from 38.436 to 39.037, respectively. These features indicate that the granitoidswithin the Xitian pluton were formed from magmas generated by remelting of metapelite and metapsammite of the Paleoproterozoic metamorphic basement at temperatures of ca. 800 °C, with low oxygen fugacity. The Sr-Nd isotopic compositions of the rocks from Xitian pluton indicate that the granitic magmas were mixed with less than 10% mantle-derived magmas. We suggest that the Xitian pluton was emplaced in an extensional tectonic setting related to release of compressional stresses within the thickened crust during the early Mesozoic.

  16. The Aguilar pluton (23°12‧ S-65°40‧ W; NW Argentina): Petrological implications on the origin of the Late Jurassic intraplate magmatism in the Central Andes

    Science.gov (United States)

    Omarini, Ricardo H.; Gioncada, Anna; Vezzoli, Luigina; Mazzuoli, Roberto; Cristiani, Chiara; Sureda, Ricardo J.

    2013-11-01

    The Late Jurassic Aguilar pluton is located in NW Argentina, about 300-400 Km east of the Tarapacá basin, representing the backarc basin linked to the Jurassic volcanic arc. This small-size and compositionally heterogeneous pluton intruded the metasedimentary rocks of the Ordovician Santa Victoria Group, along the Cobres-Salinas Grandes lineament. A revision of published geochemical data in the light of new field and petrological results, allows us to propose a model concerning the petrogenesis and emplacement mechanisms of Aguilar pluton and to discuss its geodynamic setting. The pluton is mainly composed of metaluminous and nearly peraluminous granitoids, showing the geochemical characteristics of ferroan granites. The volumetrically subordinate mafic rocks are both ne- and hy-normative, and their primary magmas were generated by partial melting of a pristine Proterozoic mantle. Aguilar rocks display a rather limited range in (87Sr/86Sr)i, compared to the entire rift-related plutonic suite, i.e., 0.703198-0.704601, and ɛNdt from -1.06 to 3.82, calculated at 149 Ma. Fractional crystallization of mantle-derived magmas and crustal contamination processes explain the evolution to produce strongly silica-oversaturated magmas, which emplaced in the continental crust. The petrological data indicate that magma emplacement and cooling occurred at rather shallow depth. Multiple injections of magma batches into the magma chamber caused mingling and mixing processes early in the crystallization history. The Aguilar pluton is one of the several igneous complexes whose formation was associated with the extensional tectonics active during Late Jurassic-Early Cretaceous in NW Argentina. Based on the geological position and the igneous rocks affinity, we exclude that the Late Jurassic magmatism was generated in an orogenic setting and envisage that it was linked to the early extensional phase that preceded the Cretaceous continental rifting, related to the break-up of the South

  17. Chemical U-Th-Pb Monazite Dating of Deformations versus Pluton Emplacement and the Proterozoic History of the Arkansas River Region,Colorado, USA

    Institute of Scientific and Technical Information of China (English)

    CAO Hui

    2009-01-01

    Five lengthy periods involving multiple phases of cordierite and andalusite growth were revealed by detailed studies of foliation inflection/intersection axes (FIA) preserved in porphyroblasts in schists from the Arkansas River region in Colorado, USA. The regionally consistent character of the succession of five different FIA trends enabled the relative timing of each FIA with respect to the next to be determined. The FIA succession from first to last is: FIA 1 trending W-E, FIA 2 trending SSW-NNE, FIA 3 trending NNW-SSE, FIA 4 trending NW-SE and FIA 5 trending SW-NE. For four of the FIA sets, samples were found containing monazite grains preserved as inclusions. These were dated on an electron microprobe. The ages obtained concur exactly with the FIA succession, with FIA 1 at 1506±15 Ma, FIA 2 at 1467±23 Ma, FIA 3 at 1425±18 Ma, FIA 4 not dated and FIA 5 at 1366±20 Ma.These ages are directly reflected in a succession of plutons in the surrounding region dated by other isotopic approaches, suggesting that deformation, metamorphism and pluton emplacement occurred together episodically, but effectively continuously, for some 140 Ma.

  18. Geochemical evidence for contribution of ore-forming materials from peraluminous granite basement-- Taking Fucheng pluton and No. 6722 uranium deposit in southern Jiangxi Province as examples

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Bangtong(章邦桐); CHEN; Peirong(陈培荣); YANG; Dongsheng(杨东生); KONG; Xinggong(孔兴功)

    2003-01-01

    Using the induced fission-track method, mobile uranium leaching and lead isotope analysis, this work obtianed geochemical features of the peraluminous Fucheng granite basement and the host rock (shoshonite) of the No. 6722 uranium deposit in southern Jiangxi Province. (i) Uranium contents of the leucocratic rock-forming minerals (0.18 ?g/g for quartz, 0.36 ?g/g for feldspar) are lower than the uranium content of the whole rock (4.6 ?g/g). Biotite and some accessory mineral inclusions (zircon, monazite and uraninite) are the main uranium carriers of the Fucheng granite pluton. The fissure uranium in altered minerals (hydromica and chlorite) increased evidently. (ii) Leachable rate of mobile uranium in the biotite granite is 10.4%, while that in the altered granite increased to 31%. (iii) Caculation based on lead isotopes shows that during alteration the Fucheng granite lost uranium (?U = ?37% - ?65%), whereas the Caotaobei shoshonite gained uranium (?U = +37%- +58%). These features suggest that the ore-forming material of the No. 6722 uranium deposit was mainly derived from the altered peraluminous granite basement of Fucheng pluton.

  19. Emplacement age for the mafic-ultramafic plutons in the northern Dabie Mts. (Hubei): Zircon U-Pb, Sm-Nd and 40Ar/39Ar dating

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The protoliths of mafic-ultramafic plutons in the northern Dabie Mts. (NDM) (Hubei) include pyroxenite and gabbro. The zircon U-Pb dating for a gabbro suggests that emplacement of mafic magma took place in the post-collisional setting at the age of 122.9(0.6 Ma. It is difficult to obtain a reliable Sm-Nd isochron age, due to disequilibrium of the Sm-Nd isotopic system. Two hornblende 40Ar/39Ar ages of 116.1(1.1 Ma and 106.6(0.8 Ma may record cooling of metamorphism in the mafic-ultramafic plutons in Hubei below 500(C. The hornblende 40Ar/39Ar ages for the mafic-ultramafic rocks in Hubei are evidently 15-25 Ma younger than those for the same rocks in Anhui, indicating that there is a diversity of the cooling rates for the mafic-ultramafic rocks in Hubei and Anhui. The difference in their cooling rates may be controlled by the north-dipping normal faults in the NDM. The intense metamorphism occurring in the mafic-ultramafic rocks in Hubei may result from the Yanshanian magmatic reheating and thermal fluid action induced by the Cretaceous migmatization. The geochemical similarity of these mafic-ultramafic rocks wherever in Hubei and Anhui may be attributed to the same tectonic setting via an identical genetic mechanism.

  20. Reference levels of natural radioactivity and (137)Cs in and around the surface soils of Kestanbol pluton in Ezine region of Çanakkale province, Turkey.

    Science.gov (United States)

    Öztürk, Buket Canbaz; Çam, N Füsun; Yaprak, Günseli

    2013-01-01

    The aim of the study was to conduct a systematic investigation on the natural gamma emitting radionuclides ((226)Ra, (232)Th and (40)K) as well as (137)Cs in the surface soils from Kestanbol/Ezine plutonic area in Çanakkale province as part of the environmental monitoring program on radiologic impact of the granitoid areas in Western Anatolia. The activity measurements of the gamma emitters in the surface soil samples collected from 52 sites distributed all over the region has been carried out, by means of HPGe gamma-ray spectrometry system. The activity concentrations of the relevant radionuclides in the soil samples appeared in the ranges as follows: (226)Ra was 20-521 Bq kg(-1); (232)Th, 11-499 Bq kg(-1)and; (40)K, 126-3181 Bq kg(-1), yet the (137)Cs was much lower than 20 Bq kg(-1)at most. Furthermore, based on the available data, the radiation hazard parameters associated with the surveyed soils were calculated. The present data also allowed evaluation of some correlations that may exist in the investigated natural radionuclides of the soil samples from the plutonic area in Çanakkale province. It is concluded from the above that the concerned region did not lead to any significant radiological exposure to the environment.

  1. [Analysis of X-Ray Fluorescence Spectroscopy and Plasma Mass Spectrometry of Pangxidong Composite Granitoid Pluton and Its Implications for Magmatic Differentiation].

    Science.gov (United States)

    Zeng, Chang-yu; Ding, Ru-xin; Li, Hong-zhong; Zhou, Yong-zhang; Niu, Jia; Zhang, Jie-tang

    2015-11-01

    Pangxidong composite granitoid pluton located in the southwestern margin of Yunkai massif. The metamorphic grade of this pluton increases from outside to inside, that is, banded-augen granitic gneisses, gneissoid granites and granites distribute in order from edge to core. X-Ray Fluorescence Spectroscopy and Plasma Mass Spectrometry are conducted to study the geochemical characteristics of the three types of rocks. The result shows that all the three types of rocks are peraluminous rocks and their contents of main elements and rare earth elements change gradually. From granitic gneisses to granites, the contents of Al₂O₃, CaO, MgO, TiO₂, total rare earth elements and light rare earth elements increase, but the contents of SiO₂ and heavy rare earth elements decrease. It is suggested that the phylogenetic relationship exists between granitic gneisses, gneissoid granites and granites during the multi-stage tectonic evolution process. Furthermore, the remelting of metamorphosed supracrustal rocks in Yunkai massif is probably an important cause of granitoid rocks forming. The evolutionary mechanism is probably that SiO₂ and heavy rare earth elements were melt out from the protolith and gradually enriched upward, but Al₂O₃, CaO, MgO, TiO₂ and light rare earth elements enriched downward.

  2. Origin and tectonic implications of the ∼200 Ma, collision-related Jerai pluton of the Western Granite Belt, Peninsular Malaysia

    Science.gov (United States)

    Jamil, Azmiah; Ghani, Azman A.; Zaw, Khin; Osman, Syamir; Quek, Long Xiang

    2016-09-01

    Triassic granitoids (∼200-225 Ma) are widespread in the Western Belt of Peninsular Malaysia. The Main Range granite is the biggest batholith in the Western Belt composed of peraluminous to metaluminous granite and granodiorite and displays typical ilmenite-series characteristics. Jerai granitic pluton occurs at the northwestern part of the Main Range granite batholith. The Jerai granite can be divided into three facies: (i) biotite-muscovite granite; (ii) tourmaline granite; and (iii) pegmatite and aplopegmatite. Biotite-muscovite granite accounts for 90% of the Jerai pluton, and the rest is tourmaline granite. Geochemical data reveal that pegmatite and tourmaline granite are more differentiated than biotite-muscovite granite. Both pegmatite and tourmaline granite have a higher SiO2 content (70.95-83.94% versus 69.45-73.35%) and a more pronounced peraluminous character. The U-Pb zircon geochronology of the Jerai granite gave an age ranging from 204 ± 4.3 Ma, 205 ± 4 Ma and 205 ± 2 Ma for pegmatite biotite-muscovite granite and tourmaline granite, respectively. The biotite-muscovite Jerai granites are similar to S-type Main Range granite, but the tourmaline granite has a signature of late-stage hydrothermal fluid interaction such as tourmaline quartz pods, the accumulation of large pegmatitic K-feldspar, pronounced peraluminous character, higher SiO2 content. Age evidence of these two granitic facies suggest that they are from the same magma.

  3. Rb-Sr, Pb-Pb, U-Pb dating in the Bandja plutonic series of Western Cameroon. Donnees geochronologiques (Rb-Sr, Pb-Pb, U-Pb) sur le complexe plutonique de Bandja (Centre-Ouest Cameroun)

    Energy Technology Data Exchange (ETDEWEB)

    Tchankam, C.N. (Nancy-1 Univ., 54 (France)); Vialette, Y. (Clermont-Ferrand-2 Univ., 63 - Aubiere (France))

    1994-08-01

    The results of U-Pb zircon and Pb-Pb on minerals and whole rocks are reported on a charnockite syn-D1 from the Bandja series in the western Cameroon. Data are interpreted as representing a plutonic emplacement at 640 Ma. A syn- to post-tectonic pluton is dated at 557 [+-] 8 Ma (Rb-Sr whole rocks isochron). These results confirm the Pan-African age of the charnockitic intrusive body. Initial isotopic [sup 87]Sr/[sup 86]Sr ratios of charnockite (0.709) and granite (0.7089) show the importance of crustal imprint in the magma genesis. (authors).

  4. Studies on Fast Remediation of Soda Meadow Alkaline Soil

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lianren; SUN Yankun; LI Dawei

    2010-01-01

    Researches on models of remediation quickly in soda meadow alkaline soil, and dynamic variation of water-salt in saline soil of Zhaozhou County were studied systematically from 2001 to 2006. Realize the vegetation cover of those years through the artificial planting, mixed seeding lymc grass (Elymus dahuricus Turcz) and melilot in the mode of rotary tillage and deep loosening in lower and medium saline soils. The results showed that there was remarkable relationship between net evaporation (difference of precipitation and evaporation) and total salt content in the soil. The net evaporation could be used as a new method to forecast the dynamics variation of salt to ensure the pasture optimum sowing time. Realize the autumnal vegetation cover of those years through direct planting on the bourgeon layer of soda meadow alkaline soil, on the other hand, the covered pasture made the function of restraining salt and alkaline content to realize the biology reverse succession quickly. Forage seeds were seeded directly on the seeding bed of soda alkaline meadow at the end of July. In fall of the same year, a certain amount of biomass was obtained. The model, which has remarkable economical efficiency and use widely, represented the innovative model for the fast vegetation restoration on the soda alkaline meadow soil.

  5. Tourmaline occurrences within the Penamacor-Monsanto granitic pluton and host-rocks (Central Portugal): genetic implications of crystal-chemical and isotopic features

    Science.gov (United States)

    da Costa, I. Ribeiro; Mourão, C.; Récio, C.; Guimarães, F.; Antunes, I. M.; Ramos, J. Farinha; Barriga, F. J. A. S.; Palmer, M. R.; Milton, J. A.

    2014-04-01

    Tourmalinization associated with peraluminous granitic intrusions in metapelitic host-rocks has been widely recorded in the Iberian Peninsula, given the importance of tourmaline as a tracer of granite magma evolution and potential indicator of Sn-W mineralizations. In the Penamacor-Monsanto granite pluton (Central Eastern Portugal, Central Iberian Zone), tourmaline occurs: (1) as accessory phase in two-mica granitic rocks, muscovite-granites and aplites, (2) in quartz (±mica)-tourmaline rocks (tourmalinites) in several exocontact locations, and (3) as a rare detrital phase in contact zone hornfels and metapelitic host-rocks. Electron microprobe and stable isotope (δ18O, δD, δ11B) data provide clear distinctions between tourmaline populations from these different settings: (a) schorl-oxyschorl tourmalines from granitic rocks have variable foititic component (X□ = 17-57 %) and Mg/(Mg + Fe) ratios (0.19-0.50 in two-mica granitic rocks, and 0.05-0.19 in the more differentiated muscovite-granite and aplites); granitic tourmalines have constant δ18O values (12.1 ± 0.1 ‰), with wider-ranging δD (-78.2 ± 4.7 ‰) and δ11B (-10.7 to -9.0 ‰) values; (b) vein/breccia oxyschorl [Mg/(Mg + Fe) = 0.31-0.44] results from late, B- and Fe-enriched magma-derived fluids and is characterized by δ18O = 12.4 ‰, δD = -29.5 ‰, and δ11B = -9.3 ‰, while replacement tourmalines have more dravitic compositions [Mg/(Mg + Fe) = 0.26-0.64], close to that of detrital tourmaline in the surrounding metapelitic rocks, and yield relatively constant δ18O values (13.1-13.3 ‰), though wider-ranging δD (-58.5 to -36.5 ‰) and δ11B (-10.2 to -8.8 ‰) values; and (c) detrital tourmaline in contact rocks and regional host metasediments is mainly dravite [Mg/(Mg + Fe) = 0.35-0.78] and oxydravite [Mg/(Mg + Fe) = 0.51-0.58], respectively. Boron contents of the granitic rocks are low (Monsanto pluton, either as direct tourmaline precipitation in cavities and fractures crossing the

  6. Metasomatized lithosphere and the origin of alkaline lavas.

    Science.gov (United States)

    Pilet, Sébastien; Baker, Michael B; Stolper, Edward M

    2008-05-16

    Recycled oceanic crust, with or without sediment, is often invoked as a source component of continental and oceanic alkaline magmas to account for their trace-element and isotopic characteristics. Alternatively, these features have been attributed to sources containing veined, metasomatized lithosphere. In melting experiments on natural amphibole-rich veins at 1.5 gigapascals, we found that partial melts of metasomatic veins can reproduce key major- and trace-element features of oceanic and continental alkaline magmas. Moreover, experiments with hornblendite plus lherzolite showed that reaction of melts of amphibole-rich veins with surrounding lherzolite can explain observed compositional trends from nephelinites to alkali olivine basalts. We conclude that melting of metasomatized lithosphere is a viable alternative to models of alkaline basalt formation by melting of recycled oceanic crust with or without sediment.

  7. ADVANCES IN THE MODEL OF CYLINDRICAL ALKALINE CELLS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The advancement of a systematic investigation on the modeling of cylindrical alkaline cells is presented.Initial analysis utilizes thermodynamic and kinetic information to predict alkaline cell performance under low discharge rates.Subsequent modling has taken into consideration detailed information on the chemistry of electrode reactions,mass tranport of dissolved species,physical and chemical properties of the electrolyte and solid phases,and internal geonetry of cell systems.The model is capable of predicting alkaline cell performance under a variety of dicharge conditions.The model also provides information regarding internal cell changes during discharge.The model is the basis of a rational approach for the optimal design of cells.

  8. Alkaline Comet Assay for Assessing DNA Damage in Individual Cells.

    Science.gov (United States)

    Pu, Xinzhu; Wang, Zemin; Klaunig, James E

    2015-08-06

    Single-cell gel electrophoresis, commonly called a comet assay, is a simple and sensitive method for assessing DNA damage at the single-cell level. It is an important technique in genetic toxicological studies. The comet assay performed under alkaline conditions (pH >13) is considered the optimal version for identifying agents with genotoxic activity. The alkaline comet assay is capable of detecting DNA double-strand breaks, single-strand breaks, alkali-labile sites, DNA-DNA/DNA-protein cross-linking, and incomplete excision repair sites. The inclusion of digestion of lesion-specific DNA repair enzymes in the procedure allows the detection of various DNA base alterations, such as oxidative base damage. This unit describes alkaline comet assay procedures for assessing DNA strand breaks and oxidative base alterations. These methods can be applied in a variety of cells from in vitro and in vivo experiments, as well as human studies.

  9. POLYETHER POLYURETHANE FROM MODIFIED WHEAT STRAW OXYGEN-ALKALINE LIGNIN

    Institute of Scientific and Technical Information of China (English)

    QuanxiaoLiu; HuaiyuZhan; BeihaiHe; ShuhuiYang; JianhuaLiu; JianluLiu(1); ZhenxingPang

    2004-01-01

    Polyether polyurethane was synthesized from modified wheat straw oxygen-alkaline lignin, polyethylene glycol and two different diisocyanates (diphenylemethane-4, 4'-diisocyanate, tolulene diisocyanate) by solution casting method, its properties were investigated. The results show that modified wheat straw oxygen-alkaline lignin can substitute part of polyethylene glycol to react with diisocyanate to synthesize polyurethane. The molar ratio of NCO to OH and modified wheat straw oxygen-alkaline lignin content affect the properties of lignin-based polyether polyurethane respectively. The addition of plasticizer in the polyurethane synthesis process improves the properties of synthesized polyurethane, especially the elasticity of polyurethane. The synthesized polyurethane from modified wheat straw oxygen-alkali lignin can be used as both engineering plastic and hard foam plastic in future.

  10. POLYETHER POLYURETHANE FROM MODIFIED WHEAT STRAW OXYGEN-ALKALINE LIGNIN

    Institute of Scientific and Technical Information of China (English)

    Quanxiao Liu; Huaiyu Zhan; Beihai He; Shuhui Yang; Jianhua Liu; Jianlu Liu; Zhenxing Pang

    2004-01-01

    Polyether polyurethane was synthesized from modified wheat straw oxygen-alkaline lignin,polyethylene glycol and two different diisocyanates (diphenylemethane-4, 4′-diisocyanate, tolulene diisocyanate) by solution casting method, its properties were investigated. The results show that modified wheat straw oxygen-alkaline lignin can substitute part of polyethylene glycol to react with diisocyanate to synthesize polyurethane. The molar ratio of NCO to OH and modified wheat straw oxygen-alkaline lignin content affect the properties of lignin-based polyether polyurethane respectively. The addition of plasticizer in the polyurethane synthesis process improves the properties of synthesized polyurethane, especially the elasticity of polyurethane. The synthesized polyurethane from modified wheat straw oxygen-alkali lignin can be used as both engineering plastic and hard foam plastic in future.

  11. Origin and significance of the Permian high-K calc-alkaline magmatism in the central-eastern Southern Alps, Italy

    Science.gov (United States)

    Rottura, A.; Bargossi, G. M.; Caggianelli, A.; Del Moro, A.; Visonà, D.; Tranne, C. A.

    1998-12-01

    The Atesina Volcanic District, the Monte Luco volcanics, and the Cima d'Asta, Bressanone-Chiusa, Ivigna, Monte Croce and Monte Sabion intrusions, in the central-eastern Southern Alps, form a wide calc-alkaline association of Permian age (ca. 280-260 Ma). The magmatism originated during a period of post-orogenic extensional/transtensional faulting which controlled the magma ascent and emplacement. The magmatic products are represented by a continuum spectrum of rock types ranging from basaltic andesites to rhyolites, and from gabbros to monzogranites, with preponderance of the acidic terms. They constitute a metaluminous to weakly peraluminous series showing mineralogical, petrographic and chemical characteristics distinctive of the high-K calc-alkaline suites. In the MORB-normalized trace element diagrams, the most primitive volcanic and plutonic rocks (basaltic andesites and gabbros with Mg No.=66 to 70; Ni=25 to 83 ppm; Cr=248 to 679 ppm) show LILE and LREE enriched patterns with troughs at Nb-Ta and Ti, a distinctive feature of subduction-related magmas. Field, petrographic, geochemical and isotopic evidence (initial 87Sr/ 86Sr ratios from 0.7057 to 0.7114; ɛNd values from -2.7 to -7.4; ∂ 18O values between 7.6 and 9.5‰) support a hybrid nature for both volcanic and plutonic rocks, originating through complex interactions between mantle-derived magmas and crustal materials. Only the scanty andalusite-cordierite and orthopyroxene-cordierite bearing peraluminous granites in the Cima d'Asta and Bressanone-Chiusa intrusive complexes can be interpreted as purely crustal melts (initial 87Sr/ 86Sr=0.7143-0.7167; initial ɛNd values between -7.9 and -9.6, close to average composition of the granulitic metasedimentary crust from the Ivrea Zone in the western Southern Alps). Although the Permian magmatism shows geochemical characteristics similar to those of arc-related suites, palaeogeographic restorations, and geological and tectonic evidence, seem not to support

  12. 2nd Generation alkaline electrolysis. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Yde, L. [Aarhus Univ. Business and Social Science - Centre for Energy Technologies (CET), Aarhus (Denmark); Kjartansdottir, C.K. [Technical Univ. of Denmark. DTU Mechanical Engineering, Kgs. Lyngby (Denmark); Allebrod, F. [Technical Univ. of Denmark. DTU Energy Conversion, DTU Risoe Campus, Roskilde (Denmark)] [and others

    2013-03-15

    The overall purpose of this project has been to contribute to this load management by developing a 2{sup nd} generation of alkaline electrolysis system characterized by being compact, reliable, inexpensive and energy efficient. The specific targets for the project have been to: 1) Increase cell efficiency to more than 88% (according to the higher heating value (HHV)) at a current density of 200 mA /cm{sup 2}; 2) Increase operation temperature to more than 100 degree Celsius to make the cooling energy more valuable; 3) Obtain an operation pressure more than 30 bar hereby minimizing the need for further compression of hydrogen for storage; 4) Improve stack architecture decreasing the price of the stack with at least 50%; 5) Develop a modular design making it easy to customize plants in the size from 20 to 200 kW; 6) Demonstrating a 20 kW 2{sup nd} generation stack in H2College at the campus of Arhus University in Herning. The project has included research and development on three different technology tracks of electrodes; an electrochemical plating, an atmospheric plasma spray (APS) and finally a high temperature and pressure (HTP) track with operating temperature around 250 deg. C and pressure around 40 bar. The results show that all three electrode tracks have reached high energy efficiencies. In the electrochemical plating track a stack efficiency of 86.5% at a current density of 177mA/cm{sup 2} and a temperature of 74.4 deg. C has been shown. The APS track showed cell efficiencies of 97%, however, coatings for the anode side still need to be developed. The HTP cell has reached 100 % electric efficiency operating at 1.5 V (the thermoneutral voltage) with a current density of 1. 1 A/cm{sup 2}. This track only tested small cells in an externally heated laboratory set-up, and thus the thermal loss to surroundings cannot be given. The goal set for the 2{sup nd} generation electrolyser system, has been to generate 30 bar pressure in the cell stack. An obstacle to be

  13. Direct Promotion of Collagen Calcification by Alkaline Phosphatase

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Alkaline phosphatase promotes hydrolysis of phosphate containing substrates, causes a rise in inorganic phosphate and, therefore, enhances calcification of biological tissues. In this work, the calcification of collagen in a model serum was used as a model of collagenous tissue biomaterials to study the possible calcification promotion mechanism of alkaline phosphatase. In the enzyme concentration range of 0.10.5mg/mL, the enzyme shows a direct calcification promoting effect which is independent of the hydrolysis of its phosphate containing substrates but proportional to the enzyme concentration. Potassium pyrophosphate somewhat inhibits the calcification promotion.

  14. Research on Alkaline Filler Flame-Retarded Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    HU Shuguang; ZHANG Houji; WANG Jiaolan

    2006-01-01

    Used as flame retardant of tunnel asphalt pavement, organic bromides produce a large amount of poisons and smoke in construction and flame retardation stage. The alkaline filler was found to replace mineral filler, and the flame-retarded asphalt mixtures were produced. Experimental results show that these asphalt mixtures are smoke restrained; the performances and construction technology of asphalt pavement are not influenced; also the alkaline filler is of low-price. So this kind of flame-retarded asphalt mixtures is suitable for tunnel pavement.

  15. Impact of Alkaline Dust Pollution on Soil Microbial Biomass Carbon

    OpenAIRE

    Kara, Ömer; Bolat, İlyas

    2007-01-01

    The effect of alkaline dust pollution emitted from Bartın cement plant on the soil microbial biomass carbon was investigated using the chloroform fumigation-extraction (CFE) method. Microbial biomass C (Cmic) values ranged from 157.82 to 1201.51 µg g-1 soils in the polluted area and from 726.70 to 1529.14 µg g-1 soils in the control area. Soils polluted with alkaline cement dust resulted in significant reductions in Cmic levels compared to control soils. Microbial biomass C correlated negativ...

  16. Immobilization of cesium in alkaline activated fly ash matrix

    Science.gov (United States)

    Fernandez-Jimenez, A.; Macphee, D. E.; Lachowski, E. E.; Palomo, A.

    2005-11-01

    The immobilization potential of alkaline activated fly ash (AAFA) matrices for cesium has been investigated. The presence of Cs in the AAFA pastes, prepared using 8M NaOH solution as activator, showed no significant adverse effects on mechanical strength or microstructure, nor were significant quantities of Cs leached following application of the Toxic Characteristic Leaching Procedure (TCLP) and American Nuclear Society (ANS) 16.1 leaching protocols. Microstructural analysis shows Cs associated with the main reaction product in the AAFA suggesting that cesium is chemically bound rather than physically encapsulated. It is proposed that cesium is incorporated into the alkaline aluminosilicate gel, a precursor for zeolite formation.

  17. Alkaline protease production by solid state fermentation on polyurethane foam

    OpenAIRE

    Hongzhang, Chen; Hui, Wang; Aijun, Zhang; Zuohu, Li

    2006-01-01

    This paper investigated the process of solid state fermentation (SSF) using PUF (polyurethane foam) as inert solid support to produce alkaline protease. Maximal enzyme activity was 2185U/ml at pH 9.0, incubation temperature 32 0C inoculum amount of 1.0 % (v/v) , nutrient solution3.75 ml/g PUF, incubation time for 2 h and 15.0 mM of added CaCl2. Under the same conditions, the yield of alkaline protease produced by SSF using PUF as support is higher than that by submerged fermentation (SMF).

  18. Advances in alkaline cooling water treatment technology: An update

    Energy Technology Data Exchange (ETDEWEB)

    Shaffer, A.E. Jr.; Klatskin, S.D.

    1985-01-01

    A series of chromate and non-chromate treatment programs, specifically designed for alkaline pH cooling waters, have been developed. The treatments provide excellent corrosion and scale control over a broad range of water chemistries and are applicable to high conductivity and iron contaminated waters. Low levels of zinc are used to reduce the dependency on alkalinity, chromate and calcium carbonate supersaturation for corrosion control. The precipitation and fouling problems previously encountered with zinc containing treatments have been eliminated by the use of polymeric dispersants.

  19. Application conditions for ester cured alkaline phenolic resin sand

    Institute of Scientific and Technical Information of China (English)

    Ren-he Huang; Bao-ping Zhang; Yao-ji Tang

    2016-01-01

    Five organic esters with different curing speeds: propylene carbonate (i.e. high-speed ester A); 1, 4-butyrolactone; glycerol triacetate (i.e. medium-speed ester B); glycerol diacetate; dibasic ester (DBE) (i.e. low-speed ester C), were chosen to react with alkaline phenolic resin to analyze the application conditions of ester cured alkaline phenolic resin. The relationships between the curing performances of the resin (including pH value, gel pH value, gel time of resin solution, heat release rate of the curing reaction and tensile strength of the resin sand) and the amount of added organic ester and curing temperature were investigated. The results indicated the folowing: (1) The optimal added amount of organic ester should be 25wt.%-30wt.% of alkaline phenolic resin and it must be above 20wt.%-50 wt.% of the organic ester hydrolysis amount. (2) High-speed ester A (propylene carbonate) has a higher curing speed than 1, 4-butyrolactone, and they were both used as high-speed esters. Glycerol diacetate is not a high-speed ester in alkaline phenolic resin although it was used as a high-speed ester in ester cured sodium silicate sand; glycerol diacetate and glycerol triacetate can be used as medium-speed esters in alkaline phenolic resin. (3) High-speed ester A, medium-speed ester B (glycerol triacetate) and low-speed ester C (dibasic ester, i.e., DBE) should be used below 15 ºC, 35 ºC and 50 ºC, respectively. High-speed ester A or low-speed ester C should not be used alone but mixed with medium-speed ester B to improve the strength of the resin sand. (4) There should be a suitable solid content (generaly 45wt.%-65wt.% of resin), alkali content (generaly 10wt.%-15wt.% of resin) and viscosity of alkaline phenolic resin (generaly 50-300 mPa·s) in the preparation of alkaline phenolic resin. Finaly, the technique conditions of alkaline phenolic resin preparation and the application principles of organic ester were discussed.

  20. Surface-treatment of Alkaline Earth Sulfides Based Phosphor

    Institute of Scientific and Technical Information of China (English)

    GUO Chong-feng; CHU Ben-li; XU Jian; SU Qiang

    2004-01-01

    A series of alkaline earth sulfides based phosphors Ca0.8Sr0.2S∶Eu2+, Tm3+ were covered with a layer of protective coating with alkaline earth fluorides by heating the mixture of phosphor and NH4HF2 at elevated temperatures. The coatings were characterized by means of XRD and SEM. The optical properties of the coated phosphors and the influences of the coating on their properties have been discussed extensively. The stabilities of the coated and uncoated phosphors have been compared.

  1. Human placental alkaline phosphatase electrophoretic alleles: Quantitative studies

    Science.gov (United States)

    Lucarelli, Paola; Scacchi, Renato; Corbo, Rosa Maria; Benincasa, Alberto; Palmarino, Ricciotti

    1982-01-01

    Human placental alkaline phosphatase (ALP) activity has been determined in specimens obtained from 562 Italian subjects. The mean activities of the three common homozygotes (Pl 2 = 4.70 ± 0.24, Pl 1 = 4.09 ± 0.08, and Pl 3 = 2.15 ± 0.71 μmol of p-nitrophenol produced) were significantly different. The differences among the various allelic forms account for 10% of the total quantitative variation of the human placental alkaline phosphatase. PMID:7072721

  2. Impact of Alkaline Dust Pollution on Soil Microbial Biomass Carbon

    OpenAIRE

    KARA, Ömer; Bolat, İlyas

    2014-01-01

    The effect of alkaline dust pollution emitted from Bartın cement plant on the soil microbial biomass carbon was investigated using the chloroform fumigation-extraction (CFE) method. Microbial biomass C (Cmic) values ranged from 157.82 to 1201.51 µg g-1 soils in the polluted area and from 726.70 to 1529.14 µg g-1 soils in the control area. Soils polluted with alkaline cement dust resulted in significant reductions in Cmic levels compared to control soils. Microbial biomass C correlated negativ...

  3. Igneous evolution of a complex laccolith-caldera, the Solitario, Trans-Pecos Texas: Implications for calderas and subjacent plutons

    Science.gov (United States)

    Henry, C.D.; Kunk, M.J.; Muehlberger, W.R.; McIntosh, W.C.

    1997-01-01

    laccocaldera followed this sequence of events, our field and 40Ar/39Ar data demonstrate that it developed through repeated, episodic magma injections, separated by 0.4 to 0.6 m.y. intervals of little or no activity. This evolution requires a deep, long-lived magma source, well below the main laccolith. Laccoliths are commonly thought to be small, shallow features that are not representative of major, silicic magmatic systems such as calderas and batholiths. In contrast, we suggest that magma chambers beneath many ashflow calderas are tabular, floored intrusions, including laccoliths. Evidence for this conclusion includes the following: (1) many large plutons are recognized to be laccoliths or at least tabular, (2) the Solitario and several larger calderas are known to have developed over laccoliths, and (3) magma chambers beneath calderas, which are as much as 80 km in diameter, cannot be as deep as they are wide or some would extend into the upper mantle. The Solitario formed during a tectonically neutral period following Laramide deformation and preceding Basin and Range extension. Therefore, space for the main laccolith was made by uplift of its roof and possibly subsidence of the floor, not by concurrent faulting. Laccolith-type injection is probably a common way that space is made for magma bodies of appreciable areal extent in the upper crust.

  4. SHRIMP zircon U-Pb dating and geochemical characteristics of Shihama granite pluton in northeastern Hunan province%湘东北地区石蛤蟆花岗岩体SHRIMP U—Pb年龄及地球化学特征

    Institute of Scientific and Technical Information of China (English)

    姚宇军; 马铁球; 周柯军; 柏道远

    2012-01-01

    分布于湖南东北部的石蛤蟆岩体侵位于新元古代地层中。由微细粒斑状黑云母花岗闪长岩和细粒斑状黑云母二长花岗岩等两期侵入体组成。通过锆石SHRIM PU--Pb法测得岩体侵位年龄为157土2Ma(2d),MSWD=0.98,成岩时代为晚侏罗世。SiO2=68.26%~68.53%,K2O/Na2O=1.37~1.59,岩石属镁质、准铝质-微过铝质、高钾钙碱性-钾玄岩系列;岩石明显富集大离子亲石元素,亏损高场强元素,Rb/Sr较低(0.40~0.56);乏REE较高(171.48~183.81),Eu为弱负异常(δEu=0.86~0.93),(La/Yb)N=27.11~45.87;具较高的eNd值(-5.11)和高T2DM(1.63Ga)。综合研究表明,石蛤蟆花岗岩为混合源高钾钙碱性花岗岩类(KCG),其花岗岩浆有大量幔源物质加入。讨论认为岩体形成于构造体制转换下的地球动力学背景,是造山晚期张弛作用下的产物。%Distributed in northeastern Hunan province and intruded in Neoproterozoic strata, Shihama granite pluton is mainly composed of micro-fine-grained porphyritic biotite granodiorites of early stage and fine- grained porphyritic biotite monzonitic granites of late stage. SHRIMP zircon dating of the granites gives an age of 157±2 Ma which belongs to Late Jurassic. The granites belong to magnesian, metaluminous-weak- ly peraluminous, high-K calc-alkaline-shoshonite series, with SIO2=68.26% -68.53M and K2O/Na2O= 1.37 - 1.59. The rocks show enriched large-ion lithophile elements, depleted high field-strength ele- ments, low values of Rb/Sr(0.40-0.56), high values of ∑REE (171.48-183.81), with δEu=0.86-- 0. 93, (La/Yb)N=27. 11-45.87, εNd=5.11, T2DM=1. 63 Ga. Studies indicate that the Shihama gran- ites belong to high-K calc-alkaline granites (KCG) originated form the crust-mantled mixed source ivolving large amount of mantle source materials. It is believed that the granite pluton is the result of

  5. Middle Triassic magma mixing in an active continental margin: Evidence from mafic enclaves and host granites from the Dewulu pluton in West Qinling, central China

    Science.gov (United States)

    Huang, X.; Mo, X.; Yu, X.

    2015-12-01

    The Qinling-Dabie-Sulu orogen was formed through the collision of the North and South China blocks, but the precise timing of the closure of the Paleo-Tethys ocean between the two blocks remains debated. Large volumes of Triassic granites associated with mafic microgranular enclaves (MMEs) were emplaced in the Qinling terrane. This paper presents field observations, petrography, geochronology and geochemistry of the MMEs and their host granites from the Dewulu pluton in West Qinling. The host rocks comprise granodiorite and granodioritic porphyry, and the The MMEs range in composition from gabbroic diorite to diorite. Zircon LA-ICP-MS U-Pb ages suggest that the granites and MMEs were coeval at ca. 245 Ma. The granites are relatively enriched in LILE and depleted in HFSE, and have evolved Sr-Nd-Pb and zircon Hf isotopic compositions [initial 87Sr/86Sr = 0.7070-0.7076, ɛNd(t) = -7.5 to -6.8, ɛHf(t) = -8.2 to -4.2], indicative of an origin from the amphibolitic lower crust. The near-primitive gabbro-dioritic MMEs bear a remarkable geochemical resemblance to the high-magnesium andesite (HMA), such as moderate SiO2 (~55 wt.%), low FeOT/MgO (~0.75), high Cr (268-308 ppm) and MgO (8.58-8.77 wt.%) with Mg# of ~70. Additionally, they exhibit lower initial 87Sr/86Sr, higher ɛNd(t) and ɛHf(t), and more radiogenic Pb isotopes than the dioritic MMEs which share similar isotopic compositions with the granites. These features, together with the presence of the specific minerals in the MMEs (e.g., felsic xenocrysts and acicular apatite), point to mixing process between the lower crust-derived magmas and the melts produced by the reaction of the subducting sediment-derived components and the overlying mantle. Taking into account the regional occurrence of synchronous plutonic-volcanic complexes (250-234 Ma) ranging from basaltic to granitic variants, we suggest that the Dewulu pluton formed in an active continental margin in response to the local extension triggered by the

  6. Time relationships between volcanism-plutonism-alteration-mineralization in Cu-stratabound ore deposits from the Michilla mining district, northern Chile: a 40Ar/39Ar geochronological approach

    Science.gov (United States)

    Oliveros, Verónica; Tristá-Aguilera, Dania; Féraud, Gilbert; Morata, Diego; Aguirre, Luis; Kojima, Shoji; Ferraris, Fernando

    2008-01-01

    The Michilla mining district comprises one of the most important stratabound and breccia-style copper deposits of the Coastal Cordillera of northern Chile, hosted by the Middle Jurassic volcanic rocks of the La Negra Formation. 40Ar/39Ar analyses carried out on igneous and alteration minerals from volcanic and plutonic rocks in the district allow a chronological sequence of several magmatic and alteration events of the district to be established. The first event was the extrusion of a thick lava series of the La Negra Formation, dated at 159.9 ± 1.0 Ma (2 σ) from the upper part of the series. A contemporaneous intrusion is dated at 159.6 ± 1.1 Ma, and later intrusive events are dated at 145.5 ± 2.8 and 137.4 ± 1.1 Ma, respectively. Analyzed alteration minerals such as adularia, sericite, and actinolite apparently give valid 40Ar/39Ar plateau and miniplateau ages. They indicate the occurrence of several alteration events at ca. 160-163, 154-157, 143-148, and 135-137 Ma. The first alteration event, being partly contemporaneous with volcanic and plutonic rocks, was probably produced in a high thermal gradient environment. The later events may be related either to a regional low-grade hydrothermal alteration/metamorphism process or to plutonic intrusions. The Cu mineralization of the Michilla district is robustly bracketed between 163.6 ± 1.9 and 137.4 ± 1.1 Ma, corresponding to dating of actinolite coexisting with early-stage chalcocite and a postmineralization barren dyke, respectively. More precisely, the association of small intrusives (a dated stock from the Michilla district) with Cu mineralization in the region strongly suggests that the main Michilla ore deposit is related to a magmatic/hydrothermal event that occurred between 157.4 ± 3.6 and 163.5 ± 1.9 Ma, contemporaneous or shortly after the extrusion of the volcanic sequence. This age is in agreement with the Re-Os age of 159 ± 16 Ma obtained from the mineralization itself (Tristá-Aguilera et al

  7. Extracellular Alkalinization as a Defense Response in Potato Cells

    Science.gov (United States)

    Moroz, Natalia; Fritch, Karen R.; Marcec, Matthew J.; Tripathi, Diwaker; Smertenko, Andrei; Tanaka, Kiwamu

    2017-01-01

    A quantitative and robust bioassay to assess plant defense response is important for studies of disease resistance and also for the early identification of disease during pre- or non-symptomatic phases. An increase in extracellular pH is known to be an early defense response in plants. In this study, we demonstrate extracellular alkalinization as a defense response in potatoes. Using potato suspension cell cultures, we observed an alkalinization response against various pathogen- and plant-derived elicitors in a dose- and time-dependent manner. We also assessed the defense response against a variety of potato pathogens, such as protists (Phytophthora infestans and Spongospora subterranea) and fungi (Verticillium dahliae and Colletotrichum coccodes). Our results show that extracellular pH increases within 30 min in proportion to the number of pathogen spores added. Consistently with the alkalinization effect, the higher transcription level of several defense-related genes and production of reactive oxygen species was observed. Our results demonstrate that the alkalinization response is an effective marker to study early stages of defense response in potatoes. PMID:28174578

  8. Bone alkaline phosphatase and mortality in dialysis patients

    NARCIS (Netherlands)

    C. Drechsler; M. Verduijn; S. Pilz; R.T. Krediet; F.W. Dekker; C. Wanner; M. Ketteler; E.W. Boeschoten; V. Brandenburg

    2011-01-01

    Serum alkaline phosphatase (AP) is associated with vascular calcification and mortality in hemodialysis patients, but AP derives from various tissues of origin. The aim of this study was to assess the effect of bone-specific AP (BAP) on morbidity and mortality in dialysis patients. From a prospectiv

  9. Alkalinity and hardness: Critical but elusive concepts in aquaculture

    Science.gov (United States)

    Total alkalinity and total hardness are familiar variables to those involved in aquatic animal production. Aquaculturists – both scientists and practitioners alike – tend to have some understanding of the two variables and of methods for adjusting their concentrations. The chemistry and the biolog...

  10. Induction of glomerular alkaline phosphatase after challenge with lipopolysaccharide

    NARCIS (Netherlands)

    Kapojos, Jola Jovita; Poelstra, Klaas; Borghuis, Theo; van den Berg, Anke; Baelde, Hans J.; Klok, P.A; Bakker, W.W

    2003-01-01

    Alkaline phosphatase (AP) can be considered as a host defence molecule since this enzyme is able to detoxify bacterial endotoxin at physiological pH. The question emerged whether this anti-endotoxin principle is inducible in the glomerulus and if so, which glomerular cells might be involved in the e

  11. The catalytic properties of alkaline phosphatases under various conditions

    Science.gov (United States)

    Atyaksheva, L. F.; Chukhrai, E. S.; Poltorak, O. M.

    2008-11-01

    A comparative study was performed to examine the catalytic properties of alkaline phosphatases from bacteria Escherichia coli and bovine and chicken intestines. The activity of enzyme dimers and tetramers was determined. The activity of the dimer was three or four times higher than that of the tetramer. The maximum activity and affinity for 4-nitrophenylphosphate was observed for the bacterial alkaline phosphatase ( K M = 1.7 × 10-5 M, V max = 1800 μmol/(min mg of protein) for dimers and V max = 420 μmol/(min mg of protein) for tetramers). The Michaelis constants were equal for two animal phosphatases in various buffer media (pH 8.5) ((3.5 ± 0.2) × 10-4 M). Five buffer systems were investigated: tris, carbonate, hepes, borate, and glycine buffers, and the lowest catalytic activity of alkaline phosphatases at equal pH was observed in the borate buffer (for enzyme from bovine intestine, V max = 80 μmol/(min mg of protein)). Cu2+ cations formed a complex with tris-(oxymethyl)-aminomethane ( tris-HCl buffer) and inhibited the intestine alkaline phosphatases by a noncompetitive mechanism.

  12. Chromatographic separation of alkaline phosphatase from dental enamel

    DEFF Research Database (Denmark)

    Moe, D; Kirkeby, S; Salling, E

    1989-01-01

    Alkaline phosphatase (AP) was prepared from partly mineralized bovine enamel by extraction in phosphate buffer, centrifugation and various chromatographic techniques. Chromatofocusing showed that the enamel enzyme possessed five isoelectric points at the acid pH level ranging from pH 5.7 to pH 4....

  13. Dephosphorylation of endotoxin by alkaline phosphatase in vivo

    NARCIS (Netherlands)

    Poelstra, Klaas; Bakker, W.W; Klok, P.A; Kamps, J.AAM; Hardonk, M.J; Meijer, D.K F

    1997-01-01

    Natural substrates for alkaline phosphatase (AP) are at present not identified despite extensive investigations. Difficulties in imagining a possible physiological function involve its extremely high pH optimum for the usual exogenous substrates and its localization as an ecto-enzyme. As endotoxin i

  14. Alkaline polymer electrolyte fuel cells: Principle, challenges, and recent progress

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Polymer electrolyte membrane fuel cells (PEMFC) have been recognized as a significant power source in future energy systems based on hydrogen. The current PEMFC technology features the employment of acidic polymer electrolytes which, albeit superior to electrolyte solutions, have intrinsically limited the catalysts to noble metals, fundamentally preventing PEMFC from widespread deployment. An effective solution to this problem is to develop fuel cells based on alkaline polymer electrolytes (APEFC), which not only enable the use of non-precious metal catalysts but also avoid the carbonate-precipitate issue which has been troubling the conventional alkaline fuel cells (AFC). This feature article introduces the principle of APEFC, the challenges, and our research progress, and focuses on strategies for developing key materials, including high-performance alkaline polyelectrolytes and stable non-precious metal catalysts. For alkaline polymer electrolytes, high ionic conductivity and satisfactory mechanical property are difficult to be balanced, therefore polymer cross-linking is an ultimate strategy. For non-precious metal catalysts, it is urgent to improve the catalytic activity and stability. New materials, such as transition-metal complexes, nitrogen-doped carbon nanotubes, and metal carbides, would become applicable in APEFC.

  15. Soil salinity and alkalinity in the Great Konya Basin, Turkey

    NARCIS (Netherlands)

    Driessen, P.M.

    1970-01-01

    In the summers of 1964 to 1968 a study was made of soil salinity and alkalinity in the Great Konya Basin, under the auspices of the Konya Project, a research and training programme of the Department of Tropical Soil Science of the Agricultural University, Wageningen.The Great Konya Basin, some 300 k

  16. Transcriptome Analysis of Enterococcus faecalis in Response to Alkaline Stress

    Directory of Open Access Journals (Sweden)

    Ran eshujun

    2015-08-01

    Full Text Available E. faecalis is the most commonly isolated species from endodontic failure root canals; its persistence in treated root canals has been attributed to its ability to resist high pH stress. The goal of this study was to characterize the E. faecalis transcriptome and to identify candidate genes for response and resistance to alkaline stress using Illumina HiSeq 2000 sequencing.We found that E. faecalis could survive and form biofilms in a pH 10 environment and that alkaline stress had a great impact on the transcription of many genes in the E. faecalis genome. The transcriptome sequencing results revealed that 613 genes were differentially expressed (DEGs for E. faecalis grown in pH 10 medium; 211 genes were found to be differentially up-regulated and 402 genes differentially down-regulated. Many of the down-regulated genes found are involved in cell energy production and metabolism and carbohydrate and amino acid metabolism, and the up-regulated genes are mostly related to nucleotide transport and metabolism. The results presented here reveal that cultivation of E. faecalis in alkaline stress has a profound impact on its transcriptome. The observed regulation of genes and pathways revealed that E. faecalis reduced its carbohydrate and amino acid metabolism and increased nucleotide synthesis to adapt and grow in alkaline stress. A number of the regulated genes may be useful candidates for the development of new therapeutic approaches for the treatment of E. faecalis infections.

  17. Solvent Extraction of Alkaline Earth Metals with Alkylphosphorus Acids

    Institute of Scientific and Technical Information of China (English)

    XUXin; ZHUTun

    2002-01-01

    Solvent extraction equiliria of four main alkaline earth metals (magnesium, calcium, strontium and barium) with di(2-ethylhexyl) phosphoric acid (DEHPA), 2-ethylhexyl phosphonic acid mono-(2-ethylhexyl) ester, di(2,4,4-tri-methylpentyl) phosphinic acid and IR spectra of the extracts have been studied. The selectivity order is dependent of the e/r value and hydration energy of the metal ions. The minor shift of the P→O in IR absorption of the alkaline earth metal extracts indicates that the interaction between the metal ions and P→O is much weaker for alkaline earth metals than for transitional metals. The distribution of the four alkaline earth elements between aqueous solutions and solutions of DEHPA and neutral organophosphorus compunds, tri-n-butyl phosphate (TBP) or tri-octyl phosphine oxide (TOPO) in kerosene have been determined at varying ratio of TBP or TOPO to DEHPA and the positive synergism is observed. The synergic effects is explained by using IR spectra of the loaded organic phase.

  18. Determination of the density of zinc powders for alkaline battery

    Institute of Scientific and Technical Information of China (English)

    Beatriz Ares Tejero; David Guede Carnero

    2007-01-01

    The density of zinc powder for alkaline battery was determined using a pyknometer.The results showed that powders made before the end of 2003 could reach relative densities above 99% of the theoretical density.Investigating the relative volume swelling of electrolysed gels of zinc powders,no evident relation between swelling and pyknometer density was found.

  19. Endotoxin detoxification by alkaline phosphatase in cholestatic livers

    NARCIS (Netherlands)

    Poelstra, K; Bakker, WW; Hardonk, MJ; Meijer, DKF; Wisse, E; Knook, DL; Balabaud, C

    1997-01-01

    Increased expression of alkaline phosphatase (AP) in the liver is a hallmark of cholestasis but the pathophysiological role of this is not clear. We argue that deprotonation of carboxyl groups at the active site of the enzyme may be a prerequisite for optimal AP activity. Such a creation of negative

  20. Curing mechanism of alkaline phenolic resin with organic ester

    Institute of Scientific and Technical Information of China (English)

    Huang Renhe; Wang Yanmin; Zhang Baoping

    2014-01-01

    To study the curing mechanism of alkaline phenolic resin with organic ester, three esters were chosen to react with three systems - alkaline phenolic resin, potassium hydroxide aqueous solution containing phenol, and potassium hydroxide aqueous solution. The variations of pH, heat release and gel pH during the reactions were monitored and measured. Infrared spectroscopy (IR) and thermal gravity analysis (TG) techniques were used to characterize the curing reaction. It was found that organic ester is only partial y hydrolyzed and resin can be cured through organic ester hydrolysis process as wel as the reaction with redundant organic ester. The sequential curing mechanism of alkaline phenolic resin cured by organic ester was identified as fol ows: a portion of organic ester is firstly hydrolyzed owing to the effect of the strong alkaline; the gel is then formed after the pH decreases to about 10.8-10.88, meanwhile, the redundant organic ester (i.e. non-hydrolysis ester) starts the curing reaction with the resin. It has also been found that the curing rate depends on the hydrolysis velocity of organic ester. The faster the hydrolysis speed of the ester, the faster the curing rate of the resin.

  1. Kinetic characteristics of acidic and alkaline ceramidase in human epidermis

    NARCIS (Netherlands)

    Houben, E.; Uchida, Y.; Nieuwenhuizen, W.F.; Paepe, K. de; Vanhaecke, T.; Holleran, W.M.; Rogiers, V.

    2007-01-01

    It has recently become evident that at least five ceramidase (CDase) isoforms are present in human epidermis, and that specifically acidic CDase (aCDase) and alkaline CDase (alkCDase) activities increase during keratinocyte differentiation, and thus might play a pivotal role(s) in permeability barri

  2. Field screening of cowpea cultivars for alkaline soil tolerance

    Science.gov (United States)

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at soil pH of 7.5 or higher, cowp...

  3. Yield performance of cowpea genotypes grown in alkaline soils

    Science.gov (United States)

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at soil pH of 7.5 or higher, cowp...

  4. Geochronology of plutonic rocks and their tectonic terranes in Glacier Bay National Park and Preserve, southeast Alaska: Chapter E in Studies by the U.S. Geological Survey in Alaska, 2008-2009

    Science.gov (United States)

    Brew, David A.; Tellier, Kathleen E.; Lanphere, Marvin A.; Nielsen, Diane C.; Smith, James G.; Sonnevil, Ronald A.

    2014-01-01

    We have identified six major belts and two nonbelt occurrences of plutonic rocks in Glacier Bay National Park and Preserve and characterized them on the basis of geologic mapping, igneous petrology, geochemistry, and isotopic dating. The six plutonic belts and two other occurrences are, from oldest to youngest: (1) Jurassic (201.6–145.5 Ma) diorite and gabbro of the Lituya belt; (2) Late Jurassic (161.0–145.5 Ma) leucotonalite in Johns Hopkins Inlet; (3) Early Cretaceous (145.5–99.6 Ma) granodiorite and tonalite of the Muir-Chichagof belt; (4) Paleocene tonalite in Johns Hopkins Inlet (65.5–55.8 Ma); (5) Eocene granodiorite of the Sanak-Baranof belt; (6) Eocene and Oligocene (55.8–23.0 Ma) granodiorite, quartz diorite, and granite of the Muir-Fairweather felsic-intermediate belt; (7) Eocene and Oligocene (55.8–23.0 Ma) layered gabbros of the Crillon-La Perouse mafic belt; and (8) Oligocene (33.9–23.0 Ma) quartz monzonite and quartz syenite of the Tkope belt. The rocks are further classified into 17 different combination age-compositional units; some younger belts are superimposed on older ones. Almost all these plutonic rocks are related to Cretaceous and Tertiary subduction events. The six major plutonic belts intrude the three southeast Alaska geographic subregions in Glacier Bay National Park and Preserve, from west to east: (1) the Coastal Islands, (2) the Tarr Inlet Suture Zone (which contains the Border Ranges Fault Zone), and (3) the Central Alexander Archipelago. Each subregion includes rocks assigned to one or more tectonic terranes. The various plutonic belts intrude different terranes in different subregions. In general, the Early Cretaceous plutons intrude rocks of the Alexander and Wrangellia terranes in the Central Alexander Archipelago subregion, and the Paleogene plutons intrude rocks of the Chugach, Alexander, and Wrangellia terranes in the Coastal Islands, Tarr Inlet Suture Zone, and Central Alexander Archipelago subregions.

  5. Energetics of Amino Acid Synthesis in Alkaline Hydrothermal Environments

    Science.gov (United States)

    Kitadai, Norio

    2015-12-01

    Alkaline hydrothermal systems have received considerable attention as candidates for the origin and evolution of life on the primitive Earth. Nevertheless, sufficient information has not yet been obtained for the thermodynamic properties of amino acids, which are necessary components for life, at high temperatures and alkaline pH. These properties were estimated using experimental high-temperature volume and heat capacity data reported in the literature for several amino acids, together with correlation algorithms and the revised Helgeson-Kirkham-Flowers (HKF) equations of state. This approach enabled determination of a complete set of the standard molal thermodynamic data and the revised HKF parameters for the 20 protein amino acids in their zwitterionic and ionization states. The obtained dataset was then used to evaluate the energetics of amino acid syntheses from simple inorganic precursors (CO2, H2, NH3 and H2S) in a simulated alkaline hydrothermal system on the Hadean Earth. Results show that mixing between CO2-rich seawater and the H2-rich hydrothermal fluid can produce energetically favorable conditions for amino acid syntheses, particularly in the lower-temperature region of such systems. Together with data related to the pH and temperature dependences of the energetics of amino acid polymerizations presented in earlier reports, these results suggest the following. Hadean alkaline hydrothermal settings, where steep pH and temperature gradients may have existed between cool, slightly acidic Hadean ocean water and hot, alkaline hydrothermal fluids at the vent-ocean interface, may be energetically the most suitable environment for the synthesis and polymerization of amino acids.

  6. Role of dust alkalinity in acid mobilization of iron

    Directory of Open Access Journals (Sweden)

    A. Ito

    2010-04-01

    Full Text Available Atmospheric processing of mineral aerosols by acid gases (e.g., SO2, HNO3, N2O5, and HCl may play a key role in the transformation of insoluble iron (Fe2O3 to soluble forms (e.g., Fe(II, inorganic soluble species of Fe(III, and organic complexes of iron. However, mineral dust particles also have a potential of neutralizing the acidic species due to the alkaline buffer ability of carbonate minerals (e.g., CaCO3 and MgCO3. Here we demonstrate the impact of dust alkalinity on the acid mobilization of iron in a three-dimensional aerosol chemistry transport model, which is incorporated with a mineral dissolution scheme. In our model simulations, most of the alkaline dust minerals cannot be entirely consumed by inorganic acids during the transport across the North Pacific Ocean. As a result, the inclusion of alkaline compounds in aqueous chemistry substantially limits the iron dissolution in aerosol solution during the long-range transport. Over the North Pacific Ocean, only a small fraction (<0.2% of iron dissolves from hematite in the coarse-mode dust aerosols, when assuming internally mixed with carbonate minerals. However, if the iron-containing minerals are externally mixed with carbonate minerals, a significant amount (1–2% of iron would dissolve from the acid mobilization. It implies that the alkaline content in dust aerosols might help to explain the inverse relationship between aerosol iron solubility and particle size.

  7. Geochemistry and SHRIMP Zircon U-Pb Age of Post-Collisional Granites in the Southwest Tianshan Orogenic Belt of China: Examples from the Heiyingshan and Laohutai Plutons

    Institute of Scientific and Technical Information of China (English)

    LONG Lingli; GAO Jun; WANG Jingbin; QIAN Qing; XIONG Xianming; WANG Yuwang; WANG Lijuan; GAO Liming

    2008-01-01

    The Heiyingshan granite and the Laohutai granite plutons exposed in the Southwest Tianshan resemble A-type granites geochemically. Analysis shows that the both are ferron calc-alkalic peraluminous or ferron aikali-calcic peraluminous with a relatively high concentration of SiO2 (>70%), high alkali contents (Na2O + K2O = 7.14%-8.56%; K2O>N2O; A/CNK = 0.99-1.20), and pronounced negative anomales in Eu, Ba, Sr, P and Ti. A SHRIMP zircon U-Pb age of 285±4 Ma was obtained for the Heiyingshan hornblende biotite granite intrusion. The geochemical and age dating data reported in this paper indicate that these granites were formed during the post-collisional crustal extension of the Southwest Tianshan orogenic belt, in agreement with the published data for the granites in the South Tianshan.

  8. SHRIMP U-Pb Zircon Dating of the Tula Granite Pluton on the South Side of the Altun Fault and Its Geological Implications

    Institute of Scientific and Technical Information of China (English)

    WU Suoping; WU Cailai; WANG Meiying; CHEN Qilong; Joseph L. WOODEN

    2008-01-01

    The Tula A2-subtype granite pluton is located between the Altun fault and its branching fault.According to the geological, geochemical, REE and trace elements characteristics, it belongs to the A2 (PA) subtype granite. The SHRIMP U-Pb zircon dating gives a result of 385.2+8.1 Ma, which is located between the Middle and Late Devonian in the international stratigraphic chart, and can be regarded as the crystallization age of the Tula granite. The study indicates that the Tula area was in a local extensional environment in the end of the Middle Devonian, and that environment was probably related to the synchronized strike-slip activity of the Altun fault.

  9. Pluton emplacement in a releasing bend in a transpressive regime: the arrozal granite in the Paraíba do Sul shear belt, Rio de Janeiro.

    Science.gov (United States)

    Nummer, Alexis R; Machado, Rômulo; Dehler, Nolan M

    2007-06-01

    The Arrozal Granite, situated in the southwestern region of the State of Rio de Janeiro, has a granitic to granodioritic composition. It contains a strong mylonitic foliation along its border, passing gradually to a well-developed magmatic foliation towards its center. Structural analysis indicates that the Arrozal Granite was emplaced along the Além-Paraíba Shear Zone in a dextral transpressive tectonic regime. A regional shift of the trend along this shear zone from NE-SW to E-W, observed in the area, is interpreted to be casually related to the creation of space for the emplacement of the granite. Our data indicate that releasing bends may have played an important role for space generation during the emplacement of the Arrozal Granite and other plutons.

  10. The Montalet granite, Montagne Noire, France: An Early Permian syn-extensional pluton as evidenced by new U-Th-Pb data on zircon and monazite

    Science.gov (United States)

    Poilvet, Jean-Charles; Poujol, Marc; Pitra, Pavel; Van Den Driessche, Jean; Paquette, Jean-Louis

    2011-07-01

    Dating the magmatism in the Montagne Noire gneiss dome in the southern French Massif Central is a key point for understanding the Late Palaeozoic evolution of this part of the Variscan belt, which is characterised by compressive tectonics during the Carboniferous and extensional tectonics during Stephanian-Permian times. The Montalet granite crops out in the north-western part of the dome and was first considered as an early syntectonic intrusion related to compressive deformation. More recently, it has been dated at 327 Ma and considered as contemporaneous with the diapiric ascent of the Montagne Noire gneiss dome before the Stephanian-Permian extension. We show that in fact, this pluton was emplaced 294 ± 1 Ma ago and is therefore contemporaneous with the Stephanian-Permian extension. This age is consistent with the interpretation of the Montagne Noire Massif as an extensional gneiss dome.

  11. The Capilla del Monte pluton, Sierras de Córdoba, Argentina: the easternmost Early Carboniferous magmatism in the pre-Andean SW Gondwana margin

    Science.gov (United States)

    Dahlquist, Juan A.; Pankhurst, Robert J.; Rapela, Carlos W.; Basei, Miguel A. S.; Alasino, Pablo H.; Saavedra, Julio; Baldo, Edgardo G.; Murra, Juan A.; da Costa Campos Neto, Mario

    2016-07-01

    New geochronological, geochemical, and isotopic data are reported for the Capilla del Monte two-mica granite pluton in the northeastern Sierras de Córdoba. An Early Carboniferous age is established by a U-Pb zircon concordia (336 ± 3 Ma) and a Rb-Sr whole-rock isochron (337 ± 2 Ma). Zircon saturation geothermometry indicates relatively high temperatures (735-800 °C). The granites have high average SiO2 (74.2 %), Na2O + K2O (7.8 %), and high field-strength elements, high K2O/Na2O (1.7) and FeO/MgO ratios (5.1), with low CaO content (0.71 %). REE patterns with marked negative Eu anomalies (Eu/Eu* 0.14-0.56) indicate crystal fractionation, dominantly of plagioclase and K-feldspar, from a peraluminous magma enriched in F. Isotope data (87Sr/86Srinitial = 0.7086, ɛ Nd336 = -5.5 to -4.4 with T DM = 1.5 Ga, zircon ɛ Hf336 +0.8 to -6.1; mean T DM = 1.5 Ga) suggest a Mesoproterozoic continental source, albeit with some younger or more juvenile material indicated by the Hf data. The pluton is the easternmost member of a Carboniferous A-type magmatic suite which shows an increase in juvenile input toward the west in this part of the pre-Andean margin. The petrological and geochemical data strongly suggest a similar intraplate geodynamic setting to that of the nearby but much larger, Late Devonian, Achala batholith, although Hf isotope signatures of zircon suggest a more uniformly crustal origin for the latter. Further studies are required to understand whether these bodies represent two independent magmatic episodes or more continuous activity.

  12. Mixing and mingling in the evolution of andesite dacite magmas; evidence from co-magmatic plutonic enclaves, Taupo Volcanic Zone, New Zealand

    Science.gov (United States)

    Cole, J. W.; Gamble, J. A.; Burt, R. M.; Carroll, L. D.; Shelley, D.

    2001-10-01

    The southeastern side of the Taupo Volcanic Zone, New Zealand is marked by a line of andesite/dacite/low-silica rhyolite complexes. Co-magmatic plutonic enclaves occur within the lavas of the four youngest complexes: White Island, Motuhora (Whale Island), Edgecumbe and Tauhara. The enclaves range from coarse-grained gabbros, diorites, granodiorites and a syenite to finer-grained dolerites and microdiorites. The more mafic types are generally porphyritic with large phenocrysts of plagioclase, usually with extensive sieve textures in the cores and corroded margins. Most of these enclaves, including the coarser-grained plutonic examples, contain glass and many are miarolitic. Diorites and microdiorites/dolerites predominate at White Island, Motuhora and Edgecumbe; many are porphyritic. Enclaves at Tauhara are more variable; those collected from Hipaua Dome include a range from microdiorites to quartz microdiorites and those from Rubbish Tip Dome include microdiorites, a granodiorite, and a syenite. Most enclaves show textural evidence for disequilibrium with multiple populations of plagioclase and pyroxene. They also show considerable textural variation, even within a thin section, with coarse-grained gabbros/diorites intimately mixed with finer-grained dolerites/microdiorites. Geochemically and isotopically, most enclaves have a similar composition with their host lavas, although some have lower silica contents. Enclaves at Motuhora and Tauhara are isotopically more variable, indicating multiple sources and a more complex petrogenesis. Most diorite/microdiorite enclaves are interpreted to represent parts of a crystal mush formed during fractionation of andesite/dacite magma, and entrained during later rise of magma to the surface. The granodiorite from Rubbish Tip Dome, Tauhara, probably represents part of a silicic magma chamber within the crust that fed the host low-silica rhyolite lava dome. Variability within the enclaves indicates the complexity likely to occur

  13. Screening of Alkaline Protease-Producing Streptomyces diastaticus and Optimization of Enzyme Production

    Directory of Open Access Journals (Sweden)

    Elham Dawoodi

    2014-12-01

    Full Text Available Background and Aim: Alkaline proteases are used in pharmaceutical, film and photography, silk production and food, leather and detergent industries. Actinomycetes are gram positive bacteria that produce different enzymes such as proteases. The aims of this research were isolation of native alkaline protease-producing Actinomycete spp. from different soil samples as well as optimizing the conditions for enzyme production. Materials and Methods: The different soil samples were collected from different locations of the provinces of Khouzestan, Chahar Mahalo Bakhtiari and Isfahan, Iran. After determining of the best alkaline protease producing species using Lowry method, the optimization of alkaline protease was performed. Results: The alkaline protease producing Actinomycete spp. was isolated from soil. The most enzyme activity was measured in S.diastaticus. The best concentration of sucrose as the carbon source for the highest production of alkaline protease was 10 g/l. The optimum pH and temperature for the alkaline protease production by S. diastaticus were 10 and 30°C respectively. The maximum activity of alkaline protease was measured at 200 rpm as the best aeration speed. Conclusions: This is the first report of alkaline protease production by Streptomyces diastaticus in Iran. The accomplished examinations in this research confirmed the previous theories of alkaline protease production by Actinomycetes relatively. Regarding the immense applications of alkaline proteases in several industries and isolation of a native alkaline protease producing Actinomycete, The production potential of this enzyme in our country could be accessible in the near future.

  14. Amphibole-melt trace element partitioning of fractionating calc-alkaline magmas in the lower crust: an experimental study

    Science.gov (United States)

    Nandedkar, Rohit H.; Hürlimann, Niklaus; Ulmer, Peter; Müntener, Othmar

    2016-09-01

    Ca, and Mg#. Spoon-shaped REE patterns and subchondritic Nb/Ta ratios in tonalitic to granodioritic plutonic rocks and andesitic to rhyolitic magmas directly constrained by measured trace element compositions of coexisting liquids are consistent with hornblende gabbro fractionation in the middle to lower crust. The systematic change of the measured trace element composition of fractionating calc-alkaline liquids indicates that hornblende gabbro formation in the middle to lower crust also exerts an important control on some commonly used trace element ratios such as Sr/Y, Sr/Ba or Nb/Zr.

  15. Remarkable isotopic and trace element trends in potassic through sodic Cretaceous plutons of the Yukon-Koyukuk Basin, Alaska, and the nature of the lithosphere beneath the Koyukuk terrane

    Science.gov (United States)

    Arth, Joseph G.; Criss, Robert E.; Zmuda, Clara C.; Foley, Nora K.; Patton, W. W., Jr.; Miller, T. P.

    1989-11-01

    During the period from 110 to 80 m.y. ago, a 450-km-long magmatic belt was active along the northern margin of Yukon-Koyukuk basin and on eastern Seward Peninsula. The plutons intruded Upper Jurassic(?) and Lower Cretaceous volcanic arc rocks and Cretaceous sedimentary rocks in Yukon-Koyukuk basin and Proterozoic and lower Paleozoic continental rocks in Seward Peninsula. Within Yukon-Koyukuk basin, the plutons vary in composition from calc-alkalic plutons on the east to potassic and ultrapotassic alkalic plutons on the west. Plutons within Yukon-Koyukuk basin were analyzed for trace element and isotopic compositions in order to discern their origin and the nature of the underling lithosphere. Farthest to the east, the calc-alkalic rocks of Indian Mountain pluton are largely tonalite and sodic granodiorite, and have low Rb (average 82 ppm), high Sr (>600 ppm), high chondrite-normalized (cn) Ce/Yb (16-37), low δ18O (+6.5 to +7.1), low initial 87Sr/86Sr (SIR) (0.704), and high initial 143Nd/144Nd (NIR) (0.5126). These rocks resemble those modelled elsewhere as partial melts and subsequent fractionates of basaltic or gabbroic metaigneous rocks, and may be products of melting in the deeper parts of the Late Jurassic(?) and Early Cretaceous volcanic arc. Farthest to the west, the two ultrapotassic bodies of Selawik and Inland Lake are high in Cs (up to 93 ppm), Rb (up to 997 ppm), Sr, Ba, Th, and light rare earth elements, have high (Ce/Yb)cn (30, 27), moderate to low δ18O (+8.4, +6.9), high SIR (0.712, 0.710), and moderate NIR (0.5121-0.5122). These rocks resemble rocks of Australia and elsewhere that were modelled as melts of continental mantle that had been previously enriched in large cations. This mantle may be Paleozoic or older. The farthest west alkalic pluton of Selawik Hills is largely monzonite, quartz monzonite, and granite; has moderate Rb (average 284 ppm), high Sr (>600 ppm), high (Ce/Yb)cn (15-25), moderate δ18O (+8.3 to +8.6), high SIR (0

  16. Zircon U-Pb Dating of Dayishan and Tashan Plutons in Hunan Province and Its Tectonic Implications%湖南大义山、塔山岩体锆石U-Pb年龄及其构造意义

    Institute of Scientific and Technical Information of China (English)

    李勇; 张岳桥; 苏金宝; 李建华; 董树文

    2015-01-01

    The distribution and intrusion of Early Mesozoic granites in central South China such as Dayishan pluton and Tashan pluton are closely related to folded structure in this region. Precise chronologic studies can constrain the age of the tectonic deformation. This paper report zircon U-Pb LA-ICP-MS ages of the southern part of Dayishan pluton based on dating of 3 samples:the age of the eastern margin is (171.8±1.9) Ma, that of the western margin is (169.9±1.8) Ma and that of the central part is (164.2±2.6) Ma. The zircon U-Pb LA-ICP-MS age of the eastern part of Tashan pluton is (247±5.9) Ma. Dayishan pluton experienced two phases of intrusion between 164.2 and 171.8 Ma and formed a composite pluton;after that, it experienced rapid uplift prior to 125 Ma, and then it was rapidly raised to the surface at the cooling rate of 1°C/Ma. Dayishan pluton and Tashan pluton recorded Indosinian and Yanshanian magmatic activities. The EW-trending structural zone controlled Indosinian granites, such as Yangmingshan and Tashan; the ages of Dayishan and Qitianling plutons constrain the Yanshanian tectonic deformation, and the formation of the NNE-trending folds in South China should be earlier than (171.8±1.9) Ma.%华南中部地区大义山、塔山等早中生代花岗岩的展布和侵入特征与这一时期褶皱构造之间存在着非常密切的关系,对这些岩体进行精确年代学研究,可以为构造变形时代提供年代学约束。大义山岩体南部地区锆石U-Pb LA-ICP-MS年龄为东缘(171.8±1.9) Ma、西缘(169.9±1.8) Ma、中部(164.2±2.6) Ma,塔山岩体东段为(247±5.9) Ma。大义山岩体在164.2—171.8 Ma之间经历两个期次的侵入,形成了一个复式岩体,岩体形成后至125 Ma经历了快速隆升,之后以接近1°C/Ma的冷却速率抬升到地表。大义山和塔山岩体记录了华南早中生代印支和燕山两期重要的岩浆活动。阳明山、塔山岩体等E—W向展布岩体受

  17. 周口店房山岩体西缘构造特征及其形成期次探究%Research on Structual Character and Tectonic Evolution in the Western Margin of Fangshan Pluton,Zhoukoudian

    Institute of Scientific and Technical Information of China (English)

    周学文

    2015-01-01

    Fangshan pluton composed of granodiorite developed in Yanshan fold zone during J3-K1 period in the area of Zhoukoudian. Based on the analysis of large amount of xenoliths,fractures,joints,S-C fabrics and dikes formed in the western margin of the pluton,the development of the pluton are divided into 6 tectonic stages.The results show that,the structural features of the pluton in Chechang district reflect the tectonic evolution process of different stages during its intrusion.The SN trending xenoliths reflect the extrusion features when the pluton intruded;The two NNW and SSW trending conjugated ductile shear faults formed later when the pluton began to upward coagulate;The formation of the left-lateral SEE-NWW trending brittle-ductile shear faults,the dextral EW trending brittle shear faults and pyroxene diorite dikes were the result of external force to the plastic pluton after the intrusion.When the pluton absolutely cooled down,siliceous bands and quartzite fil ed three sets of primary joints.As a result of selective weathering in the later geological period,the siliceous bands protuberance generated on the surface of the pluton.%周口店房山岩体为燕山褶皱区在J3-K1期大规模岩浆侵入形成的花岗闪长岩岩体。该文根据该岩体西缘车厂韧性剪切带内发育的大量包体、断裂、节理、S-C组构及岩脉等构造特征分析,将岩体西缘的构造演化划分为6个期次。研究认为,车厂地区房山岩体的构造特征记录了其侵位以来不同时期有序的构造演化过程,其内近SN走向的定向排列包体反映了岩体侵位时受围岩挤压的变形特征,NNW和SSW向两组共轭韧性剪切断层为岩体侵位晚期顶部开始冷凝、深部岩体上拱时的产物,SEE-NWW向脆韧性左行剪切断层和近EW向右行脆性剪切断层及其辉石闪长岩岩脉为岩体侵入末期在半固结-固结状态下受外力作用结果,三组原生节理及其硅质条带充填形成于

  18. A new electrochemical oscillatory system of bromate in alkaline solution

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A new electrochemical oscillatory system of bromate in alkaline solution is reported. In PtBromate-Alkaline solution system, two different types of electrochemical oscillations (Type Ⅰ and Type Ⅱ) can be observed. Type Ⅰ appears before hydrogen evolution and Type Ⅱ involves periodic hydrogen evolution. Type Ⅰ relates to the adsorption/desorption of the hydrogen on platinum electrode, and Type Ⅱ with periodic oscillation stems from the coupling of electrochemical reactions (the reduction of bromate and evolution hydrogen reaction) with mass transfer (diffusion and convection). More over, under the right conditions, the two types appear in different oscillatory modes, for example,simple periodical mode and mixed one, etc,, Crossed cycle in the cyclic voltammograms, which is the basiccharacteristics for electrochemical oscillatory systems, has also been observed as expected.

  19. Solubilisation of lignite during oxydesulphurization in alkaline solutions

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ., Chemical Engineering Dept. (Turkey)

    1997-12-31

    Some desulphurization processes such as oxydesulphurization in which dissolved oxygen is attached to coal particles are performed usually in alkaline solutions. Therefore, these processes are resulted in not only sulphur removal but also some solubilisation of the coal matrix. In this study three different Turkish lignite samples are subjected to various oxydesulphurization processes in which dilute solutions of NaOH, Na{sub 2}CO{sub 3}, NH{sub 4}OH or Na{sub 2}B{sub 4}O{sub 7} containing dissolved oxygen under pressure were applied. The experiments were performed in a magnetically stirred and electrically heated Parr autoclave. The extent of the solubilisation is varied depending on the type and concentration of the alkaline used, the applied temperature and the rank of the lignite sample used. (orig.)

  20. Copper Plating from Non-Cyanide Alkaline Baths

    Science.gov (United States)

    Li, Minggang; Wei, Guoying; Wang, Jianfang; Li, Meng; Zhao, Xixi; Bai, Yuze

    2014-12-01

    Non-cyanide alkaline bath was used to prepare copper thin films. Influences of various temperatures on deposition rates, surface morphologies and microstructures of films were investigated. Copper thin films prepared from non-cyanide alkaline bath show typical nodular structures. Copper films fabricated at higher temperature possess rough surface due to hydrolysis of complexing agents. According to the XRD patterns, all deposited films were crystalline and showed Cu (111), Cu (200) and Cu (220) peaks. The intensity of peak (200) increases gradually with the rise on bath temperatures. Films with maximum thickness (7.5 μm) could be obtained at the temperature of 40°C. From the cyclic voltammetry curve, it was found that the cathodic polarization decreased slightly with increase of bath temperatures. In addition, when the bath temperature was equal to 50°C, current efficiency could reach to 96.95%.

  1. Controlled charge exchange between alkaline earth metals and their ions

    Science.gov (United States)

    Gacesa, Marko; Côté, Robin

    2015-05-01

    We theoretically investigate the prospects of realizing controlled charge exchange via magnetic Feshbach resonances in cold and ultracold collisions of atoms and ions. In particular, we focus on near-resonant charge exchange in heteroisotopic combinations of alkaline earth metals, such as 9Be++10 Be9 Be+10Be+ , which exhibit favorable electronic and hyperfine structure. The quantum scattering calculations are performed for a range of initial states and experimentally attainable magnetic fields in standard coupled-channel Feshbach projection formalism, where higher-order corrections such as the mass-polarization term are explicitely included. In addition, we predict a number of magnetic Feshbach resonances for different heteronuclear isotopic combinations of the listed and related alkaline earth elements. Our results imply that near-resonant charge-exchange could be used to realize atom-ion quantum gates, as well as controlled charge transfer in optically trapped cold quantum gases. This work is partially supported by ARO.

  2. Alkylation of imidazole under ultrasound irradiation over alkaline carbons

    Energy Technology Data Exchange (ETDEWEB)

    Costarrosa, L. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain); Calvino-Casilda, V. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain); Ferrera-Escudero, S. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain); Duran-Valle, C.J. [Dpto. de Quimica Inorganica, Facultad de Ciencias, Universidad de Extremadura, Avenida de Elvas s/n, 06071 Badajoz (Spain); Martin-Aranda, R.M. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain)]. E-mail: rmartin@ccia.uned.es

    2006-06-30

    N-Alkyl-imidazole has been synthesized by sonochemical irradiation of imidazole and 1-bromobutane using alkaline-promoted carbons (exchanged with the binary combinations of Na, K and Cs). The catalysts were characterized by X-ray photoelectron spectroscopy, thermal analysis and N{sub 2} adsorption isotherms. Under the experimental conditions, N-alkyl-imidazoles can be prepared with a high activity and selectivity. It is observed that imidazole conversion increases in parallel with increasing the basicity of the catalyst. The influence of the alkaline promoter, the reaction temperature, and the amount of catalyst on the catalytic activity has been studied. For comparison, the alkylation of imidazole has also been performed in a batch reactor system under thermal activation.

  3. Lithuanian Quarry Aggregates Concrete Effects of Alkaline Corrosion Tests

    Directory of Open Access Journals (Sweden)

    Aurimas Rutkauskas

    2016-02-01

    Full Text Available Aggregate alkaline corrosion of cement in concrete is going to respond in sodium and potassium hydroxide (lye with active SiO2 found in some aggregates. During this reaction, the concrete has resulted in significant internal stresses which cause deformation of the concrete, cracking and disintegration. The reaction is slow and concrete signs of decomposition appear only after a few months or years. The study used two different aggregates quarries. Studies show that Lithuania gravel contaminated with reactive particles having amorphous silicon dioxide reacting with cement in sodium and potassium hydroxide and the resulting alkaline concrete corrosion. It was found that, according to AAR 2 large aggregates include Group II – potentially reactive because of their expansion after 14 days, higher than 0.1%.

  4. Alkaline Protease Production by a Strain of Marine Yeasts

    Institute of Scientific and Technical Information of China (English)

    WANG Ping; CHI Zhenming; MA Chunling

    2006-01-01

    Yeast strain 10 with high yield of protease was isolated from sediments of saltern near Qingdao, China.The protease had the highest activity at pH 9.0 and 45 ℃.The optimal medium for the maximum alkaline protease production of strain 10 was 2.5 g soluble starch and 2.0 g NaNO3 in 100 mL seawater with initial pH6.0.The optimal cultivation conditions for the maximum protease production were temperature 24.5 ℃, aeration rate 8.0 L min -1 and agitation speed 150 r min-1.Under the optimal conditions, 623.1 Umg-1 protein of alkaline protease was reached in the culture within 30 h of fermentation.

  5. Electrical Conductivity of Alkaline-reduced Graphene Oxide

    Institute of Scientific and Technical Information of China (English)

    WANG Huan; TIAN Hong-wei; WANG Xin-wei; QIAO Liang; WANG Shu-min; WANG Xing-li; ZHENG Wei-tao; LIU Yi-chun

    2011-01-01

    A green route using a very simple and straightforward ultrasonic process under alkaline conditions,rather than a general chemical reduction process using hydrazine,was utilized to obtain the hydrophilic reduced graphene oxide(RGO) sheets,via removing oxygen functional groups from graphene oxide(GO) and repairing the aromatic structure.It is found that the conductivity of the obtained RGO could be tuned by changing pH value in alkaline solution,and the current-voltage(Ⅰ-Ⅴ) curves of both GO and RGO are nonlinear and slightly asymmetric.Under the same applied voltage,the current of RGO is much larger than that of GO,indicating a pronounced increase in the electrical conductivity of RGO,compared to that of GO.

  6. Alkaline protease production by a strain of marine yeasts

    Science.gov (United States)

    Ping, Wang; Zhenming, Chi; Chunling, Ma

    2006-07-01

    Yeast strain 10 with high yield of protease was isolated from sediments of saltern near Qingdao, China. The protease had the highest activity at pH 9.0 and 45°C. The optimal medium for the maximum alkaline protease production of strain 10 was 2.5g soluble starch and 2.0g NaNO3 in 100mL seawater with initial pH 6.0. The optimal cultivation conditions for the maximum protease production were temperature 24.5°C, aeration rate 8.0L min-1 and agitation speed 150r min-1 Under the optimal conditions, 623.1 U mg-1 protein of alkaline protease was reached in the culture within 30h of fermentation.

  7. Chemical degradation mechanisms of membranes for alkaline membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Yoong-Kee [National Institute of Advanced Industrial Science and Technology, Umezono 1-1-1, Tsukuba (Japan); Henson, Neil J.; Kim, Yu Seung [Los Alamos National Laboratory, Los Alamos, NM (United States)

    2015-12-31

    Chemical degradation mechanisms of membranes for alkaline membrane fuel cells have been investigated using density functional theory (DFT). We have elucidated that the aryl-ether moiety of membranes is one of the weakest site against attack of hydroxide ions. The results of DFT calculations for hydroxide initiated aryl-ether cleavage indicated that the aryl-ether cleavage occurred prior to degradation of cationic functional group. Such a weak nature of the aryl-ether group arises from the electron deficiency of the aryl group as well as the low bond dissociation energy. The DFT results suggests that removal of the aryl-ether group in the membrane should enhance the stability of membranes under alkaline conditions. In fact, an ether fee poly(phenylene) membrane exhibits excellent stability against the attack from hydroxide ions.

  8. Understanding of alkaline pretreatment parameters for corn stover enzymatic saccharification

    OpenAIRE

    Chen Ye; Stevens Mark A; Zhu Yongming; Holmes Jason; Xu Hui

    2013-01-01

    Abstract Background Previous research on alkaline pretreatment has mainly focused on optimization of the process parameters to improve substrate digestibility. To achieve satisfactory sugar yield, extremely high chemical loading and enzyme dosages were typically used. Relatively little attention has been paid to reduction of chemical consumption and process waste management, which has proven to be an indispensable component of the bio-refineries. To indicate alkali strength, both alkali conce...

  9. Catalytic Diversity in Alkaline Hydrothermal Vent Systems on Ocean Worlds

    Science.gov (United States)

    Cameron, Ryan D.; Barge, Laura; Chin, Keith B.; Doloboff, Ivria J.; Flores, Erika; Hammer, Arden C.; Sobron, Pablo; Russell, Michael J.; Kanik, Isik

    2016-10-01

    Hydrothermal systems formed by serpentinization can create moderate-temperature, alkaline systems and it is possible that this type of vent could exist on icy worlds such as Europa which have water-rock interfaces. It has been proposed that some prebiotic chemistry responsible for the emergence of life on Earth and possibly other wet and icy worlds could occur as a result ofredox potential and pH gradients in submarine alkaline hydrothermal vents (Russell et al., 2014). Hydrothermal chimneys formed in laboratory simulations of alkaline vents under early Earth conditions have precipitate membranes that contain minerals such as iron sulfides, which are hypothesized to catalyze reduction of CO2 (Yamaguchi et al. 2014, Roldan et al. 2014) leading to further organic synthesis. This CO2 reduction process may be affected by other trace components in the chimney, e.g. nickel or organic molecules. We have conducted experiments to investigate catalytic properties of iron and iron-nickel sulfides containing organic dopants in slightly acidic ocean simulants relevant to early Earth or possibly ocean worlds. We find that the electrochemical properties of the chimney as well as the morphology/chemistry of the precipitate are affected by the concentration and type of organics present. These results imply that synthesis of organics in water-rock systems on ocean worlds may lead to hydrothermal precipitates which can incorporate these organic into the mineral matrix and may affect the role of gradients in alkaline vent systems.Therefore, further understanding on the electroactive roles of various organic species within hydrothermal chimneys will have important implications for habitability as well as prebiotic chemistry. This work is funded by NASA Astrobiology Institute JPL Icy Worlds Team and a NAI Director's Discretionary Fund award.Yamaguchi A. et al. (2014) Electrochimica Acta, 141, 311-318.Russell, M. J. et al. (2014), Astrobiology, 14, 308-43.Roldan, A. (2014) Chem. Comm. 51

  10. Cationic Polymers Developed for Alkaline Fuel Cell Applications

    Science.gov (United States)

    2015-01-20

    Fuel! Cells.! Macromolecules!2009,!42,!831688321.! 142 ! (27)! Ong ,!A.!L.;!Saad,!S.;!Lan,!R.;!Goodfellow,!R.!J.;!Tao,!S.:!Anionic!membrane!and...Stabilized!Per!fl!uorinated!Ionomers!for!Alkaline!Membrane!Fuel!Cells.!2013.! ! (76)! Ran,!J.;!Wu,!L.;!Varcoe,!J.!R.;! Ong ,!A.!L.;!Poynton,!S.!D.;!Xu,!T...L.;! Liu,! Y.;! Ong ,! A.! L.;! Poynton,! S.! D.;! Varcoe,! J.! R.;! Xu,! T.:! Alkali! resistant! and! conductive! guanidinium8based! anion8exchange

  11. Modelling the crystallisation of alkaline earth boroaluminosilicate glass ceramics

    DEFF Research Database (Denmark)

    Svenson, Mouritz Nolsøe; Agersted, Karsten; Holm, Paul Martin

    2014-01-01

    To investigate the potential use of a thermochemical software package (FactSage 6.2), in the design of alkaline earth boroaluminosilicate glass ceramics, experimental and modelled results on four glass ceramics were compared. Initially large discrepancies were found. These are described and related...... for the topology of multicomponent melts, before accurate prediction of phase relations within boron-containing glass ceramics can be obtained....

  12. Interaction of alkali and alkaline earth ions with Ochratoxin A

    Energy Technology Data Exchange (ETDEWEB)

    Poor, Miklos [Institute of Laboratory Medicine, University of Pecs, Pecs H-7624 (Hungary); Kunsagi-Mate, Sandor; Matisz, Gergely; Li, Yin; Czibulya, Zsuzsanna [Department of General and Physical Chemistry, University of Pecs, Pecs H-7624 (Hungary); Janos Szentagothai Research Center, Pecs H-7624 (Hungary); Peles-Lemli, Beata [Department of General and Physical Chemistry, University of Pecs, Pecs H-7624 (Hungary); Koszegi, Tamas, E-mail: koszegit@freemail.hu [Institute of Laboratory Medicine, University of Pecs, Pecs H-7624 (Hungary)

    2013-03-15

    The effect of alkali and alkaline earth ions on the chemical equilibrium of mono- and dianionic forms of the mycotoxin Ochratoxin A (OTA) and their bonding onto the surface of Bovine Serum Albumin (BSA) have been investigated by fluorescence spectroscopy and fluorescence polarization techniques. Our results show that alkali metal ions shift the chemical equilibrium towards formation of dianionic form of OTA. Furthermore, the alkaline earth ions can compete with BSA for binding to OTA when these ions are present in millimolar concentrations. Our data also highlight the possibility that the 'free' fraction of OTA (not bound onto the surface of albumin) or at least a part of it is present in cation-bound form in body fluids. These observations are supported by stability constants and quantum-chemical calculations. Among the studied alkaline metal ions magnesium showed the highest affinity towards OTA under physiological conditions. Further research is required to analyze the potential significance of Mg{sup 2+}-OTA complex in cellular uptake and/or elimination of the toxin in the human body. - Highlights: Black-Right-Pointing-Pointer Fluorescence spectroscopy reveals cation-Ochratoxin A (OTA) interactions. Black-Right-Pointing-Pointer Alkali ions shift the equilibrium of OTA to formation of a dianionic structure. Black-Right-Pointing-Pointer Alkaline earth ions directly bind to OTA in the order: Mg{sup 2+}, Ca{sup 2+}, Ba{sup 2+}. Black-Right-Pointing-Pointer Quantum chemical calculations and logK values support our experimental data.

  13. Carbonate and Bicarbonate Ion Transport in Alkaline Anion Exchange Membranes

    Science.gov (United States)

    2013-06-25

    Bicarbonate Ion Transport in Alk Block 13: Supplementary Note © 2013 . Published in Journal of the Electrochemical Society , Vol. Ed. 0 160, (9) (2013...for public release; distribution is unlimited. ... 60325.7-CH-II F994 Journal of The Electrochemical Society , 160 (9) F994-F999 (2013) 0013-4651/2013...160(9)/F994/6/$31.00 © The Electrochemical Society Carbonate and Bicarbonate Ion Transport in Alkaline Anion Exchange Membranes Andrew M. Kiss,a

  14. The Origin of Life in Alkaline Hydrothermal Vents.

    Science.gov (United States)

    Sojo, Victor; Herschy, Barry; Whicher, Alexandra; Camprubí, Eloi; Lane, Nick

    2016-02-01

    Over the last 70 years, prebiotic chemists have been very successful in synthesizing the molecules of life, from amino acids to nucleotides. Yet there is strikingly little resemblance between much of this chemistry and the metabolic pathways of cells, in terms of substrates, catalysts, and synthetic pathways. In contrast, alkaline hydrothermal vents offer conditions similar to those harnessed by modern autotrophs, but there has been limited experimental evidence that such conditions could drive prebiotic chemistry. In the Hadean, in the absence of oxygen, alkaline vents are proposed to have acted as electrochemical flow reactors, in which alkaline fluids saturated in H2 mixed with relatively acidic ocean waters rich in CO2, through a labyrinth of interconnected micropores with thin inorganic walls containing catalytic Fe(Ni)S minerals. The difference in pH across these thin barriers produced natural proton gradients with equivalent magnitude and polarity to the proton-motive force required for carbon fixation in extant bacteria and archaea. How such gradients could have powered carbon reduction or energy flux before the advent of organic protocells with genes and proteins is unknown. Work over the last decade suggests several possible hypotheses that are currently being tested in laboratory experiments, field observations, and phylogenetic reconstructions of ancestral metabolism. We analyze the perplexing differences in carbon and energy metabolism in methanogenic archaea and acetogenic bacteria to propose a possible ancestral mechanism of CO2 reduction in alkaline hydrothermal vents. Based on this mechanism, we show that the evolution of active ion pumping could have driven the deep divergence of bacteria and archaea.

  15. Combination of alkaline phosphatase anti-alkaline phosphatase (APAAP)- and avidin-biotin-alkaline phosphatase complex (ABAP)-techniques for amplification of immunocytochemical staining of human testicular tissue.

    Science.gov (United States)

    Davidoff, M S; Schulze, W; Holstein, A F

    1991-01-01

    An amplification procedure was developed for the visualization of antigens in human testis using monoclonal antibodies against desmin and vimentin. The technique combines the high sensitive and specific APAAP- and ABAP-methods. Depending on the quality of the antibodies used and the processing of the material prior to the immunocytochemical staining the amplification technique may be applied either as a single APAAP and ABAP- or as a double APAAP and ABAP-combination. Especially after the double amplification reaction a distinct increase of the staining intensity of the vimentin- (in Sertoli cells, myofibroblasts of the lamina propria, and fibroblasts of the interstitium) and desmin- (in myofibroblasts of the lamina propria and smooth muscle cells of the blood vessels) like immunoreactivity was observed. If different diazonium salts were used for the visualization of the alkaline phosphatase activity (e.g. Fast Red TR Salt, Fast Blue BB Salt) desmin- and vimentin-like immunoreactivity can be demonstrated in the same tissue section in a double sequential staining approach. For double staining, the alkaline phosphatase technique may be combined successfully with a technique or a combination that uses peroxidase as a marker.

  16. Alkaline protease from Thermoactinomyces sp. RS1 mitigates industrial pollution.

    Science.gov (United States)

    Verma, Amit; Ansari, Mohammad W; Anwar, Mohmmad S; Agrawal, Ruchi; Agrawal, Sanjeev

    2014-05-01

    Proteases have found a wide application in the several industrial processes, such as laundry detergents, protein recovery or solubilization, prion degradation, meat tenderizations, and in bating of hides and skins in leather industries. But the main hurdle in industrial application of proteases is their economical production on a large scale. The present investigation aimed to exploit the locally available inexpensive agricultural and household wastes for alkaline protease production using Thermoactinomyces sp. RS1 via solid-state fermentation (SSF) technique. The alkaline enzyme is potentially useful as an additive in commercial detergents to mitigate pollution load due to extensive use of caustic soda-based detergents. Thermoactinomyces sp. RS1 showed good protease production under SSF conditions of 55 °C, pH 9, and 50 % moisture content with potato peels as solid substrate. The presented findings revealed that crude alkaline protease produced by Thermoactinomyces sp. RS1 via SSF is of potential application in silver recovery from used X-ray films.

  17. Difference between Chitosan Hydrogels via Alkaline and Acidic Solvent Systems

    Science.gov (United States)

    Nie, Jingyi; Wang, Zhengke; Hu, Qiaoling

    2016-10-01

    Chitosan (CS) has generated considerable interest for its desirable properties and wide applications. Hydrogel has been proven to be a major and vital form in the applications of CS materials. Among various types of CS hydrogels, physical cross-linked CS hydrogels are popular, because they avoided the potential toxicity and sacrifice of intrinsic properties caused by cross-linking or reinforcements. Alkaline solvent system and acidic solvent system are two important solvent systems for the preparation of physical cross-linked CS hydrogels, and also lay the foundations of CS hydrogel-based materials in many aspects. As members of physical cross-linked CS hydrogels, gel material via alkaline solvent system showed significant differences from that via acidic solvent system, but the reasons behind are still unexplored. In the present work, we studied the difference between CS hydrogel via alkaline system and acidic system, in terms of gelation process, hydrogel structure and mechanical property. In-situ/pseudo in-situ studies were carried out, including fluorescent imaging of gelation process, which provided dynamic visualization. Finally, the reasons behind the differences were explained, accompanied by the discussion about design strategy based on gelation behavior of the two systems.

  18. Adsorptive desulfurization over hierarchical beta zeolite by alkaline treatment

    Institute of Scientific and Technical Information of China (English)

    Fuping Tian; Xiaojian Yang; Yanchun Shi; Cuiying Jia; Yongying Chen

    2012-01-01

    Hierarchical beta zeolites with SiO2/Al2O3 molar ratios of 16 to 25 were obtained by alkaline treatment in NaOH solution.The effects of treatment temperature on crystallinity,textural properties and chemical composites were studied by XRD,N2 sorption,FT-IR and XRF techniques.The desulfurization performance of parent and alkaline-treated beta zeolites was investigated by static absorption in four model fuels,containing four sulfur compounds of different molecular sizes like thiophene (TP),3-methylthiophene (3-MT),benzothiophene (BT) and dibenzothiophene (DBT),respectively.The crystallinity was observed to be successfully maintained when the treatment temperature was below 50℃.Mesoporosity of beta zeolite was evidently developed with alkaline treatment.The formation of mesopore remarkably improved the desulfurization performance for TP,3-MT,BT and DBT,especially for DBT with larger molecular diameter.Though the addition of toluene in the model fuels resulted in a significant drop of the desulfurization performance of mesoporous beta zeolite,the introduction of cerium ions to some extent mitigated the effect of toluene,which means that both the adsorbents porous structure and the adsorption mode are responsible for the desulfurization performance.The adsorbent of cerium ion-exchanged mesoporous beta showed about 80% recovery of desulfurization after the first regeneration.

  19. Alkaline flocculation of Phaeodactylum tricornutum induced by brucite and calcite.

    Science.gov (United States)

    Vandamme, Dries; Pohl, Philip I; Beuckels, Annelies; Foubert, Imogen; Brady, Patrick V; Hewson, John C; Muylaert, Koenraad

    2015-11-01

    Alkaline flocculation holds great potential as a low-cost harvesting method for marine microalgae biomass production. Alkaline flocculation is induced by an increase in pH and is related to precipitation of calcium and magnesium salts. In this study, we used the diatom Phaeodactylum tricornutum as model organism to study alkaline flocculation of marine microalgae cultured in seawater medium. Flocculation started when pH was increased to 10 and flocculation efficiency reached 90% when pH was 10.5, which was consistent with precipitation modeling for brucite or Mg(OH)2. Compared to freshwater species, more magnesium is needed to achieve flocculation (>7.5mM). Zeta potential measurements suggest that brucite precipitation caused flocculation by charge neutralization. When calcium concentration was 12.5mM, flocculation was also observed at a pH of 10. Zeta potential remained negative up to pH 11.5, suggesting that precipitated calcite caused flocculation by a sweeping coagulation mechanism.

  20. Mechanism of gold dissolving in alkaline thiourea solution

    Institute of Scientific and Technical Information of China (English)

    CHAI Li-yuan; WANG Yun-yan

    2007-01-01

    Reaction mechanism of gold dissolving in alkaline thiourea solution was studied by electrochemical methods, such as cyclic voltammetry, chronopotentiometry, AC impedance, linear sweep voltammetry. Apparent activation energy of anodic process of gold electrode dissolving in alkaline thiourea solution is 14.91 kJ/mol. Rate determining step is the process of gold thiourea complex diffusing away from electrode surface to solution. The results of AC impedance and chronopotentiometry indicate that thiourea adsorbs on gold electrode surface before dissolving in solution. There does not exist proceeding chemical reactions. Formamidine disulfide, the decomposed product of thiourea, does not participate the process of gold dissolution and thiourea complex. Species with electro-activity produced in the process of electrode reaction adsorbs on the electrode surface. In alkaline thiourea solution, gold dissolving mechanism undergoes the following courses: adsorption of thiourea on electrode surface; charge transfer from gold atom to thiourea molecule; Au[SC(NH2)2]ads+ receiving a thiourea molecule and forming stable Au[SC(NH2)2]2+; and then Au[SC(NH2)2]2+diffusing away from the electrode surface to solution, the last step is the rate-determining one.

  1. Silicon Improves Maize Photosynthesis in Saline-Alkaline Soils

    Directory of Open Access Journals (Sweden)

    Zhiming Xie

    2015-01-01

    Full Text Available The research aimed to determine the effects of Si application on photosynthetic characteristics of maize on saline-alkaline soil, including photosynthetic rate (Pn, stomatal conductance (gs, transpiration rate (E, and intercellular CO2 concentration (Ci of maize in the field with five levels (0, 45, 90, 150, and 225 kg·ha−1 of Si supplying. Experimental results showed that the values of Pn, gs, and Ci of maize were significantly enhanced while the values of E of maize were dramatically decreased by certain doses of silicon fertilizers, which meant that Si application with proper doses significantly increased photosynthetic efficiency of maize in different growth stages under stressing environment of saline-alkaline soil. The optimal dose of Si application in this experiment was 150 kg·ha−1 Si. It indicated that increase in maize photosynthesis under saline-alkaline stress took place by Si application with proper doses, which is helpful to improve growth and yield of maize.

  2. Silicon improves maize photosynthesis in saline-alkaline soils.

    Science.gov (United States)

    Xie, Zhiming; Song, Ri; Shao, Hongbo; Song, Fengbin; Xu, Hongwen; Lu, Yan

    2015-01-01

    The research aimed to determine the effects of Si application on photosynthetic characteristics of maize on saline-alkaline soil, including photosynthetic rate (P n ), stomatal conductance (g s ), transpiration rate (E), and intercellular CO2 concentration (C i ) of maize in the field with five levels (0, 45, 90, 150, and 225 kg · ha(-1)) of Si supplying. Experimental results showed that the values of P n, g s, and C i of maize were significantly enhanced while the values of E of maize were dramatically decreased by certain doses of silicon fertilizers, which meant that Si application with proper doses significantly increased photosynthetic efficiency of maize in different growth stages under stressing environment of saline-alkaline soil. The optimal dose of Si application in this experiment was 150 kg · ha(-1) Si. It indicated that increase in maize photosynthesis under saline-alkaline stress took place by Si application with proper doses, which is helpful to improve growth and yield of maize.

  3. Activation of Calf Intestinal Alkaline Phosphatase by Trifluoroethanol

    Institute of Scientific and Technical Information of China (English)

    曹志方; 徐真; 朴龙斗; 周海梦

    2001-01-01

    Alkaline phosphatase is a stable enzyme which is strongly resistant to urea, guanidine hydrochloride, acid pH, and heat. But there have been few studies on the effect of organic cosolvents on the activity and structure of alkaline phosphatase. The activity of calf intestinal alkaline phosphatase (CIAP) is markedly increased when incubated in solutions with elevated trifluoroethanol (TFE) concentrations. The activation is a time dependent course. There is a very fast phase in the activation kinetics in the mixing dead time (30 s) using convential methods. Further activation after the very fast phase follows biphasic kinetics. The structural basis of the activation has been monitored by intrinsic fluorescence and far ultraviolet circular dichroism. TFE (0 - 60%) did not lead to any significant change in the intrinsic fluorescence emission maximum, indicating no significant change in the tertiary structure of CIAP. But TFE did significantly change the secondary structure of CIAP, especially increasing α-helix content. We conclude that the activation of ClAP is due to its secondary structural change. The time for the secondary structure change induced by TFE preceds that of the activity increase. These results suggest that a rapid conformational change of ClAP induced by TFE results in the enhancement of ClAP activity, followed by further increase of this activity because of the further slightly slower rearrangements of the activated conformation. It is concluded that the higher catalytic activity of ClAP can be attained with various secondary structures.

  4. Alkalinity and trophic state regulate aquatic plant distribution in Danish lakes

    DEFF Research Database (Denmark)

    Vestergaard, Ole Skafte; Sand-Jensen, Kaj

    2000-01-01

    distinct differences in the distribution of species and growth forms among the lakes. The lakes separated into five groups of characteristic species compositions. Alkalinity was the main factor responsible for the species distribution. Lakes of high alkalinity were dominated by vascular plants...... of the elodeid growth form, lakes of intermediate alkalinity contained a variety of elodeids and vascular plants of the isoetid growth form, while lakes of low alkalinity and low pH had several isoetids and bryophytes, but very few elodeids. Alkalinity is a close descriptor of the bicarbonate concentration...

  5. Role of dust alkalinity in acid mobilization of iron

    Directory of Open Access Journals (Sweden)

    A. Ito

    2010-10-01

    Full Text Available Atmospheric processing of mineral aerosols by acid gases (e.g., SO2, HNO3, N2O5, and HCl may play a key role in the transformation of insoluble iron (Fe in the oxidized or ferric (III form to soluble forms (e.g., Fe(II, inorganic soluble species of Fe(III, and organic complexes of iron. On the other hand, mineral dust particles have a potential of neutralizing the acidic species due to the alkaline buffer ability of carbonate minerals (e.g., CaCO3 and MgCO3. Here we demonstrate the impact of dust alkalinity on the acid mobilization of iron in a three-dimensional aerosol chemistry transport model that includes a mineral dissolution scheme. In our model simulations, most of the alkaline dust minerals cannot be entirely consumed by inorganic acids during the transport across the North Pacific Ocean. As a result, the inclusion of alkaline compounds in aqueous chemistry substantially limits the iron dissolution during the long-range transport to the North Pacific Ocean: only a small fraction of iron (<0.2% dissolves from hematite in the coarse-mode dust aerosols with 0.45% soluble iron initially. On the other hand, a significant fraction of iron (1–2% dissolves in the fine-mode dust aerosols due to the acid mobilization of the iron-containing minerals externally mixed with carbonate minerals. Consequently, the model quantitatively reproduces higher iron solubility in smaller particles as suggested by measurements over the Pacific Ocean. It implies that the buffering effect of alkaline content in dust aerosols might help to explain the inverse relationship between aerosol iron solubility and particle size. We also demonstrate that the iron solubility is sensitive to the chemical specification of iron-containing minerals in dust. Compared with the dust sources, soluble iron from combustion sources contributes to a relatively marginal effect for deposition of soluble iron over the North

  6. Emplacement of the La Peña alkaline igneous complex, Mendoza, Argentina (33° S): Implications for the early Miocene tectonic regime in the retroarc of the Andes

    Science.gov (United States)

    Pagano, D. S.; Galliski, M. A.; Márquez-Zavalía, M. F.

    2014-03-01

    The La Peña alkaline complex (LPC) of Miocene age (18-19 Ma) lies on the eastern front of the Precordillera (32°41ʹ34ʺS, 68°59ʹ48″W, 1400-2900 m a.s.l.), 30 km northwest of Mendoza city, Argentina. It is a subcircular massif of 19 km2 and 5 km in diameter, intruded in the metasedimentary sequence of the Villavicencio Formation of Silurian-Devonian age. It is the result of integration of multiple pulses derived from one or more deep magma chambers, which form a suite of silicate rocks grouped into: a clinopyroxenite body, a central syenite facies with a large breccia zone at the contact with the clinopyroxenite, bodies of malignite, trachyte and syenite porphyry necks, and a system of radial and annular dikes of different compositions. Its subcircular geometry and dike system distribution are frequent features of intraplate plutons or plutons emplaced in post-orogenic settings. These morphostructural features characterize numerous alkaline complexes worldwide and denote the importance of magmatic pressures that cause doming with radial and annular fracturing, in a brittle country rock. However, in the LPC, the attitude of the internal fabric of plutonic and subvolcanic units and the preferential layout of dikes match the NW-SE extensional fractures widely distributed in the host rock. This feature indicates a strong tectonic control linked to the structure that facilitate space for emplacement, corresponding to the brittle shear zone parallel to the N-S stratigraphy of the country rock. Shearing produced a system of discontinuities, with a K fractal fracture pattern, given by the combination of Riedel (R), anti-Riedel (R‧), (P) and extensional (T) fracture systems, responsible for the control of melt migration by the opening of various fracture branches, but particularly through the NW-SE (T) fractures. Five different pulses would have ascent, (1) an initial one from which cumulate clinopyroxenite was formed, (2) a phase of mafic composition represented by

  7. Thermal effects of the Santa Eulália Plutonic Complex (southern Portugal on the meta-igneous and metasedimentary host rocks

    Directory of Open Access Journals (Sweden)

    Cruz, C.

    2014-12-01

    Full Text Available The Santa Eulália Plutonic Complex (SEPC is a late-Variscan granitic body located in the northern part of the Ossa Morena Zone, a inner zone of the Variscan Iberian Massif. The SEPC host rocks are composed of meta-igneous and metasedimentary units, from Upper Proterozoic to Paleozoic ages, with a NW-SE structure, cross-cut by the SEPC. The SEPC host rocks, with low grade metamorphism show well preserved primary sedimentary or igneous mineralogical, textural and structural features. The thermal effect induced by the SEPC is restricted to the roof pendants. At N and NE of the SEPC, textures and paragenesis resulting from thermal metamorphism, are not related to the SEPC intrusion but to a previous magmatism, controlled by the NW-SE regional anisotropies. The restriction of the thermal effects to the pluton roof may be caused by a combination of several interrelated factors: higher volume of granitic mass, thermal effect by advection of fluids and longer period of prevalence of high thermal conditions. The geochemical study of SEPC host rocks shows the heterogeneous character and diversity of metasedimentary, igneous and meta-igneous rocks. The whole rock geochemical data indicate that all the metasedimentary lithologies derived from an upper continental crustal source and the igneous and meta-igneous rocks show no evidence of metasomatic effects by the SEPC emplacement.El Complejo Plutónico de Santa Eulalia (CPSE es un cuerpo granítico tardi-Varisco situado en la parte norte de la Zona de Ossa Morena, en la zona interior del Macizo Ibérico Varisco. Las rocas encajantes del CPSE están compuestas por unidades meta-ígneas y metasedimentarias, de edades que van desde el Proterozoico Superior hasta el Paleozoico, con una estructura de dirección NW-SE, cortada por el CPSE. Las rocas encanjantes del CPSE, con metamorfismo de bajo grado conservan estructuras, mineralogía y textura primarias. El efecto térmicoinducido por el CPSE se limita a los

  8. Sphene (Titanite) as Both Monitor and Driver of Evolution of Felsic Magma: Miocene Volcanic Plutonic and Rocks of the Colorado River Region, NV-AZ, USA

    Science.gov (United States)

    Miller, C. F.; Colombini, L. L.; Wooden, J. L.; Mazdab, F. K.; Gualda, G. A.; Claiborne, L. E.; Ayers, J. C.

    2009-05-01

    Sphene is commonly the most abundant accessory mineral in metaluminous to weakly peraluminous igneous rocks. Its relatively large crystals preserve a wide array of zoning patterns and inclusions - notably, abundant other accessories and melt inclusions - and it is a major host for REE, U, Th, and HFSE. Thus it is a valuable repository of information about the history of the magmas from which it forms. Recent development of a Zr-in- sphene thermometer (Hayden et al CMP 155:529 2008) and of sensitive and precise in situ trace element analysis by SHRIMP-RG (Mazdab et al GSA abst 39:6:406 2007) permit more powerful exploitation of this repository. We have initiated a study of sphene in Miocene intrusive and extrusive rocks of the Colorado River extensional corridor for which extensive field, geochemical, and geochronological data provide context. Sphene is present as a late interstitial phase in some gabbros and diorites and common in quartz monzonites and granites. Among extrusive rocks, it occurs as phenocrysts in rhyolite lavas and tuffs that are products of small to giant eruptions (Peach Spring Tuff, >600 km3). Glasses that host sphene in the rhyolites are highly evolved (>76 wt% SiO2). Applying the Zr-in-sphene thermometer (TZr), SHRIMP-RG analyses indicate crystallization T between 730 and 810 C in both plutonic and volcanic rocks. This range is narrower than T estimates for zircon growth (Ti thermometry) for the same suite, which extend to somewhat lower and considerably higher values; zircons also tend to record more events and, evidently, longer histories. Ranges of REE patterns are variable and to some extent sample-specific, but all reveal common characteristics: (1) extremely high concentrations, especially for middle REE (maximum Sm in interiors 10-40x103 x chondrite); (2) deep negative Eu anomalies (Eu/Eu* ca. 0.1-0.2); (3) TZr and REE dropping toward rims - especially pronounced for MREE. Estimated Kds for REE from sphene rims and rhyolite glass or

  9. Oxygen and Hydrogen Isotope Values for Unaltered and Hydrothermally Altered Samples from the Cretaceous Linga Plutonic Complex of the Peruvian Coastal Batholith near Ica.

    Science.gov (United States)

    Gonzalez, L. U.; Holk, G. J.; Clausen, B. L.; Poma Porras, O. A.

    2015-12-01

    A portion of the Peruvian Coastal Batholith near Ica, Peru is being studied using stable isotopes to determine the source of hydrothermal fluids that caused propylitic, phyllic, and potassic alteration in the mineralized Linga plutonic complex. Sources of hydrothermal fluids and water/rock ratios are estimated to understand the role of such fluids in alteration during cooling. A set of 64 mineral analysis from 18 igneous samples, 7 unaltered and 11 altered, were analyzed for D/H and 18O/16O isotopes. The δ18O values for whole rocks with no apparent alteration vary from +6.8‰ to +7.9‰, with sets of δ18O mineral values indicating isotopic equilibrium at closure temperatures from 571°C to 651°C, and no interaction with meteoric water. This conclusion is bolstered by hornblende (-87‰ to -64‰) and biotite (-81‰ to -74‰) δD values Most δ18O values for samples with hydrothermal alteration suggest that alteration results from magmatic fluids; however, several analyses indicate interaction with other fluids. The high δ18O values for plagioclase (+9.3‰) and hornblende (+6.3‰) from a metamorphic aureole in volcanic host rock near a plutonic intrusion may be due to interaction with metamorphic or low temperature magmatic fluids. Plagioclase (+2.6‰) and biotite (+0.1‰) δ18O values in a sample from the Jurassic volcanic envelope indicate a significant effect from meteoric-hydrothermal fluids. An altered monzonite yielded δ18O values for quartz (+5.5‰), K-spar (+5.6‰), and magnetite (+0.4‰), also suggesting interaction with meteoric fluids. A diorite from an area with strong epidotization produced an epidote δD value of -25.8‰ and a monzonite from a highly veined area has an epidote δD value of -36.1‰ suggesting interaction with sea water. This new data indicate that the Linga complex was primarily influenced by magmatic hydrothermal fluids, but metamorphic, meteoric, and sea water may have had some influence in producing alteration

  10. Mixing and melt sources in the Miocene Aztec Wash pluton (Nevada, USA) as revealed by zircon Hf and O and whole rock Sr, Nd, and Hf isotopes

    Science.gov (United States)

    Ryan, M.; Miller, J. S.; Miller, C. F.; Bromley, S.; Davies, G. R.; Schmitt, A. K.

    2011-12-01

    The 15.6 Ma Aztec Wash Pluton (AWP) is one of several Miocene intrusions located within the northern Colorado River extensional corridor. Extensive E-W tilting of fault blocks has exposed the pluton from the roof to 5 km structural depth. Earlier field and petrologic studies subdivided the AWP into two distinct zones: (1) a Granite Zone (GZ) comprised of relatively homogeneous granite with subtle differences in textures and mineralogy; (2) a Heterogeneous Zone (HZ), which interfingers the GZ, contains evidence for mafic and felsic magma input with a wide compositional range (42-78 wt% SiO2), and abundant field evidence for hybridization. Previous whole rock geochemistry and zircon trace element analyses indicated that compositional variation was produced by multi-component mixing between mafic and felsic melts within the HZ. New whole rock Sr, Nd, and Hf isotope data from the HZ show that all rocks (including high-silica granites) formed by mixing Precambrian crust and enriched mantle, with mixtures having a large mantle fraction (≥50%). New Hf (n=189) and O (n=241) isotope analyses of zircon from samples in the HZ confirm these melt sources and provide a broader perspective on hybridization processes within the AWP. Zircon grains from all samples show heterogeneous Hf and O isotopic compositions (-5 to -18 ɛHf; 4.5-7.5% δ18O), but despite the clear signature of Precambrian crust in the whole rock data, obvious Precambrian zircons (or cores) were mostly absent; only one zircon was clearly Precambrian (ɛHf = -25). Resolvable intragrain variability is relatively limited (including the Precambrian grain, which is unzoned). Zircons from hand samples and from compositional groups also show heterogeneous ɛHf and δ18O values, although the spreads are more restricted than in the whole data set (6-10 ɛHf in granites, 5-7 ɛHf in intermediate "hybrids", 5-6 ɛHf in gabbro/diorite sheets). Oxygen isotope values for the zircons also show intra-handsample heterogeneity

  11. Tracking fluid action in Little Sark Pluton (Channel Islands, UK): a UV laserprobe Ar/Ar study of excess 40Ar

    Science.gov (United States)

    Schwenzer, S. P.; Schwanethal, J.; Tindle, A. G.; Kelley, S. P.; Sherlock, S. C.

    2011-12-01

    Little Sark pluton (Channel Islands, UK) is a weakly to moderately deformed pluton of quartz diorite composition. Zircon from Little Sark has been dated as 611.4(+2.1/-1.3) Ma [Miller et al. 1991, Tectonophysics, 312], whereas titanite has an age of 606.2±0.6 Ma. Hornblende yields an Ar-Ar age of 606.4±3.4 Ma [Dallmeyer et al., 1991, J. Geol. Soc. London 148]. The rocks show evidence for post-magmatic hydrous alteration including chloritisation of biotite, and sericite formation in feldspar. We investigated the alteration in order to understand its influence on the Ar-Ar system. Detailed petrographic investigations of two samples indicate different deformation levels - S1, (less deformed), and S2 (more deformed). The feldspar is andesine to oligoclase in composition, but contains K-rich areas with patchy and sometimes cleavage guided sericitization. Mafic minerals include hornblende and biotite (the latter partially chloritized). Ar-Ar investigations were carried out using high spatial resolution UV laser ablation gas release in combination with a Nu instruments Noblesse gas mass spectrometer using spots of 80 to 140 μm diameter. Mafic minerals in S1 have highly variable 38Ar/39Ar and 37Ar/39Ar ratios and unusually high atmospheric contents for such old samples, possibly reflecting the presence of fluid inclusions associated with the sericite, particularly in the feldspar. The apparent ages in their entirety range from 429 to 668 Ma. Hornblende yields homogeneous apparent ages, whereas the younger and older ages are measured in both micas and feldspars, whose apparent ages range from 245-670 Ma. The modal age for feldspar is around 400-450 Ma, but this may not have geological meaning. Sample S2 shows many of the same features as S1. Mafic minerals span a slightly smaller age range and feldspars display apparent ages of ~245-645 Ma with a mode around 480 Ma. The alteration of both samples appears to have been accompanied by the introduction of 40Ar-rich fluids

  12. Origin of the late Early Cretaceous granodiorite and associated dioritic dikes in the Hongqilafu pluton, northwestern Tibetan Plateau: A case for crust-mantle interaction

    Science.gov (United States)

    Li, Jiyong; Niu, Yaoling; Hu, Yan; Chen, Shuo; Zhang, Yu; Duan, Meng; Sun, Pu

    2016-09-01

    We present a detailed study of geochronology, mineral chemistries, bulk-rock major and trace element abundances, and Sr-Nd-Hf isotope compositions of the granodiorite and associated dioritic dikes in the Hongqilafu pluton at the northwestern margin of the Tibetan Plateau. The granodiorite and dioritic dikes yielded zircon U-Pb ages of 104 Ma and 100 Ma, respectively. The dioritic dikes comprise varying lithologies of gabbroic diorite, diorite porphyry and granodiorite porphyry, exhibiting a compositional spectrum from intermediate to felsic rocks. Their mineral compositions display disequilibrium features such as large major element compositional variations of plagioclase, clinopyroxene and amphibole crystals. These dioritic dikes are enriched in incompatible elements (Ba, Rb, Th, U, K) and Sr-Nd-Hf isotopes (87Sr/86Sri: 0.7066 to 0.7071, εNd(t): - 5.3 to - 7.4, εHf(t): - 3.6 to - 6.2). We suggest that the dioritic dikes were most likely derived from partial melting of mantle wedge metasomatized by the subducted/subducting seafloor with a sediment component, followed by AFC processes with fractional crystallization of clinopyroxene, amphibole and plagioclase and assimilation of lower continental crust. The mantle-wedge derived magma parental to the dioritic dikes underplated and induced the lower continental crust to melt, forming the felsic crustal magma parental to the granodiorite with mantle melt signatures and having more enriched isotope compositions (87Sr/86Sri: 0.7087 to 0.7125, εNd(t): - 9.5 to - 11.6, εHf(t): - 10.3 to - 14.1) than those of the dioritic dikes. The Hongqilafu pluton is thus the product of mantle-crust interaction at an active continental margin subduction setting over the period of several million years. This understanding further indicates that the closure timing of the Shyok back-arc basin and the collision between the Kohistan-Ladakh Arc and the Karakoram Terrane may have taken place later than 100 Ma.

  13. Gallium nitrate inhibits alkaline phosphatase activity in a differentiating mesenchymal cell culture.

    Science.gov (United States)

    Boskey, A L; Ziecheck, W; Guidon, P; Doty, S B

    1993-02-01

    The effect of gallium nitrate on alkaline phosphatase activity in a differentiating chick limb-bud mesenchymal cell culture was monitored in order to gain insight into the observation that rachitic rats treated with gallium nitrate failed to show the expected increase in serum alkaline phosphatase activity. Cultures maintained in media containing 15 microM gallium nitrate showed drastically decreased alkaline phosphatase activities in the absence of significant alterations in total protein synthesis and DNA content. However, addition of 15 microM gallium nitrate to cultures 18 h before assay for alkaline phosphatase activity had little effect. At the light microscopic and electron microscopic level, gallium-treated cultures differed morphologically from gallium-free cultures: with gallium present, there were fewer hypertrophic chondrocytes and cartilage nodules were flatter and further apart. Because of altered morphology, staining with an antibody against chick cartilage alkaline phosphatase appeared less extensive; however, all nodules stained equivalently relative to gallium-free controls. Histochemical staining for alkaline phosphatase activity was negative in gallium-treated cultures, demonstrating that the alkaline phosphatase protein present was not active. The defective alkaline phosphatase activity in cultures maintained in the presence of gallium was also evidenced when cultures were supplemented with the alkaline phosphatase substrate, beta-glycerophosphate (beta GP). The data presented suggest that gallium inhibits alkaline phosphatase activity in this culture system and that gallium causes alterations in the differentiation of mesenchymal cells into hypertrophic chondrocytes.

  14. Petrology and mineralogy of the La Peña igneous complex, Mendoza, Argentina: An alkaline occurrence in the Miocene magmatism of the Southern Central Andes

    Science.gov (United States)

    Pagano, Diego Sebastián; Galliski, Miguel Ángel; Márquez-Zavalía, María Florencia; Colombo, Fernando

    2016-04-01

    The La Peña alkaline igneous complex (LPC) is located in the Precordillera (32°41‧34″ S - 68°59‧48″ W) of Mendoza province, Argentina, above the southern boundary of the present-day flat-slab segment. It is a 19 km2 and 5 km diameter subcircular massif emplaced during the Miocene (19 Ma) in the Silurian-Devonian Villavicencio Fm. The LPC is composed of several plutonic and subvolcanic intrusions represented by: a cumulate of clinopyroxenite intruded by mafic dikes and pegmatitic gabbroic dikes, isolated bodies of malignite, a central intrusive syenite that develops a wide magmatic breccia in the contact with clinopyroxenite, syenitic and trachytic porphyries, a system of radial and ring dikes of different compositions (trachyte, syenite, phonolite, alkaline lamprophyre, tephrite), and late mafic breccias. The main minerals that form the LPC, ordered according to their abundance, are: pyroxene (diopside, hedenbergite), calcium amphibole (pargasite, ferro-pargasite, potassic-ferro-pargasite, potassic-hastingsite, magnesio-hastingsite, hastingsite, potassic-ferro-ferri-sadanagaite), trioctahedral micas (annite-phlogopite series), plagioclase (bytownite to oligoclase), K-feldspar (sanidine and orthoclase), nepheline, sodalite, apatite group minerals (fluorapatite, hydroxylapatite), andradite, titanite, magnetite, spinel, ilmenite, and several Cu-Fe sulfides. Late hydrothermal minerals are represented by zeolites (scolecite, thomsonite-Ca), epidote, calcite and chlorite. The trace element patterns, coupled with published data on Sr-Nd-Pb isotopes, suggest that the primary magma of the LPC was generated in an initially depleted but later enriched lithospheric mantle formed mainly by a metasomatized spinel lherzolite, and that this magmatism has a subduction-related signature. The trace elements pattern of these alkaline rocks is similar to other Miocene calc-alkaline occurrences from the magmatic arc of the Southern Central Andes. Mineral and whole

  15. Ethylene Inhibits Root Elongation during Alkaline Stress through AUXIN1 and Associated Changes in Auxin Accumulation.

    Science.gov (United States)

    Li, Juan; Xu, Heng-Hao; Liu, Wen-Cheng; Zhang, Xiao-Wei; Lu, Ying-Tang

    2015-08-01

    Soil alkalinity causes major reductions in yield and quality of crops worldwide. The plant root is the first organ sensing soil alkalinity, which results in shorter primary roots. However, the mechanism underlying alkaline stress-mediated inhibition of root elongation remains to be further elucidated. Here, we report that alkaline conditions inhibit primary root elongation of Arabidopsis (Arabidopsis thaliana) seedlings by reducing cell division potential in the meristem zones and that ethylene signaling affects this process. The ethylene perception antagonist silver (Ag(+)) alleviated the inhibition of root elongation by alkaline stress. Moreover, the ethylene signaling mutants ethylene response1-3 (etr1-3), ethylene insensitive2 (ein2), and ein3-1 showed less reduction in root length under alkaline conditions, indicating a reduced sensitivity to alkalinity. Ethylene biosynthesis also was found to play a role in alkaline stress-mediated root inhibition; the ethylene overproducer1-1 mutant, which overproduces ethylene because of increased stability of 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID SYNTHASE5, was hypersensitive to alkaline stress. In addition, the ethylene biosynthesis inhibitor cobalt (Co(2+)) suppressed alkaline stress-mediated inhibition of root elongation. We further found that alkaline stress caused an increase in auxin levels by promoting expression of auxin biosynthesis-related genes, but the increase in auxin levels was reduced in the roots of the etr1-3 and ein3-1 mutants and in Ag(+)/Co(2+)-treated wild-type plants. Additional genetic and physiological data showed that AUXIN1 (AUX1) was involved in alkaline stress-mediated inhibition of root elongation. Taken together, our results reveal that ethylene modulates alkaline stress-mediated inhibition of root growth by increasing auxin accumulation by stimulating the expression of AUX1 and auxin biosynthesis-related genes.

  16. Understanding of alkaline pretreatment parameters for corn stover enzymatic saccharification

    Directory of Open Access Journals (Sweden)

    Chen Ye

    2013-01-01

    Full Text Available Abstract Background Previous research on alkaline pretreatment has mainly focused on optimization of the process parameters to improve substrate digestibility. To achieve satisfactory sugar yield, extremely high chemical loading and enzyme dosages were typically used. Relatively little attention has been paid to reduction of chemical consumption and process waste management, which has proven to be an indispensable component of the bio-refineries. To indicate alkali strength, both alkali concentration in pretreatment solution (g alkali/g pretreatment liquor or g alkali/L pretreatment liquor and alkali loading based on biomass solids (g alkali/g dry biomass have been widely used. The dual approaches make it difficult to compare the chemical consumption in different process scenarios while evaluating the cost effectiveness of this pretreatment technology. The current work addresses these issues through pretreatment of corn stover at various combinations of pretreatment conditions. Enzymatic hydrolysis with different enzyme blends was subsequently performed to identify the effects of pretreatment parameters on substrate digestibility as well as process operational and capital costs. Results The results showed that sodium hydroxide loading is the most dominant variable for enzymatic digestibility. To reach 70% glucan conversion while avoiding extensive degradation of hemicellulose, approximately 0.08 g NaOH/g corn stover was required. It was also concluded that alkali loading based on total solids (g NaOH/g dry biomass governs the pretreatment efficiency. Supplementing cellulase with accessory enzymes such as α-arabinofuranosidase and β-xylosidase significantly improved the conversion of the hemicellulose by 6–17%. Conclusions The current work presents the impact of alkaline pretreatment parameters on the enzymatic hydrolysis of corn stover as well as the process operational and capital investment costs. The high chemical consumption for alkaline

  17. Hydrogen embrittlement on {alpha}-iron in high alkaline environment

    Energy Technology Data Exchange (ETDEWEB)

    Hu, R.; Habashi, M.; Galland, J. [Ecole Central Paris, Chatenay-Malabry (France)

    1994-12-31

    The partial pressure of hydrogen in concrete`s pore is very low. This hydrogen is due to the chemical reaction between the silica fumes and the alkaline solutions filling the concrete`s pore. Silica fumes are added in the concrete to increase its compression resistance. If the hydrogen pressure is low, the risk of hydrogen embrittlement is also low. However, for constructional works destined to endure more than 50 years, is this risk negligible? To answer this question, the authors have studied the hydrogen embrittlement on {alpha}-iron in alkaline solutions, in the pH range 9.5 to 13.3, presenting the liquids found in the concrete`s pores after different aging, periods. Cathodic charging has been performed for low current densities in the range 0.25 to 90 A/m{sup 2} simulating several partial pressures of hydrogen on the {alpha}-iron surface with and without EDTA inhibitor. The deformation rate was 2.5{times}10{sup {minus}5} s{sup {minus}1}. Finally {alpha}-iron samples and tensile specimens have been immersed in a mixture of silica fumes and an alkaline solution at pH 13.3 in an autoclave during 1,000 hours with the aim to measure the outgassed quantity of hydrogen under vacuum at 600C and to measure also the hydrogen embrittlement. The main conclusions of this study are as following: (1) Hydrogen embrittlement is promoted by oxide Fe{sub 3}O{sub 4} film rupture and/or hydroxide Fe(OH){sub 2}. This mechanism is efficient for current densities equivalent to a cathodic potential lower or equal to {minus}1V/NHE. (2) Silica fumes in contact with a solution of pH 13.3 provoke hydrogen release and its diffusion into the {alpha}-iron, but this quantity is not enough to embrittle it.

  18. phoD Alkaline Phosphatase Gene Diversity in Soil.

    Science.gov (United States)

    Ragot, Sabine A; Kertesz, Michael A; Bünemann, Else K

    2015-10-01

    Phosphatase enzymes are responsible for much of the recycling of organic phosphorus in soils. The PhoD alkaline phosphatase takes part in this process by hydrolyzing a range of organic phosphoesters. We analyzed the taxonomic and environmental distribution of phoD genes using whole-genome and metagenome databases. phoD alkaline phosphatase was found to be spread across 20 bacterial phyla and was ubiquitous in the environment, with the greatest abundance in soil. To study the great diversity of phoD, we developed a new set of primers which targets phoD genes in soil. The primer set was validated by 454 sequencing of six soils collected from two continents with different climates and soil properties and was compared to previously published primers. Up to 685 different phoD operational taxonomic units were found in each soil, which was 7 times higher than with previously published primers. The new primers amplified sequences belonging to 13 phyla, including 71 families. The most prevalent phoD genes identified in these soils were affiliated with the orders Actinomycetales (13 to 35%), Bacillales (1 to 29%), Gloeobacterales (1 to 18%), Rhizobiales (18 to 27%), and Pseudomonadales (0 to 22%). The primers also amplified phoD genes from additional orders, including Burkholderiales, Caulobacterales, Deinococcales, Planctomycetales, and Xanthomonadales, which represented the major differences in phoD composition between samples, highlighting the singularity of each community. Additionally, the phoD bacterial community structure was strongly related to soil pH, which varied between 4.2 and 6.8. These primers reveal the diversity of phoD in soil and represent a valuable tool for the study of phoD alkaline phosphatase in environmental samples.

  19. The 226Ra isotope activities in ground water samples drawn of two wells from the Meridional Pluton, Morungaba Granitoids, eastern Sao Paulo State; Atividades do 226Ra em aguas subterraneas extraidas de dois pocos localizados no pluton meridional, granitoides de Morungaba, SP

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Fabio de Oliveira; Silva Junior, Mario Goncalves da; Bertolla, Luciana; Ribeiro, Fernando Brenha [Sao Paulo Univ., SP (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas. Dept. de Geofisica]. E-mail: brenha@iag.usp.br

    2005-07-01

    The 226Ra activities, both in solution and associated with suspended solids, were measured in ground water samples drawn from two wells drilled in a fractured granitic aquifer from the Meridional Pluton, Morungaba Granitoids, eastern Sao Paulo State. The 226Ra isotope activities were measured in a sequence of samples collected about one month apart between March, 2003 and April 2004. The 226Ra activities were measured by radon gas emanometry. The mean dissolved 226Ra activity concentration activities observed in the two wells were (44.9 {+-} 7.1) mBq/L and (51.6 {+-} 8.8) mBq/L. The 226Ra activity of the suspend solids in a liter of these waters varied between (0,6 {+-} 0,1) mBq and (13 {+-} 1) mBq, respectively. (author)

  20. ALKALINE PHOSPHATASE ACTIVITY AS A MARKER OF DOG SEMEN FREEZABILITY

    Directory of Open Access Journals (Sweden)

    KOSINIAK-KAMYSZ K.

    2007-01-01

    Full Text Available The investigation was performed to evaluate the dog semen freezability and itsquality after thawing allowing its use for artificial insemination (AI. On the basis ofsperm motility, concentration and alkaline phosphatase (AP activity in semenplasma it was possible to establish that AP activity corresponds with the basic factorof semen examination. Significant statistical differences occurred between thequality of ejaculates which were qualified or disqualified to deep freezing and AI.These results show that AP activity in raw dog semen plasma can be used as amarker for the dog semen qualification for deep freezing and AI with 95%probability of the prognosis of the results.

  1. Fire Resistance of Wood Impregnated with Soluble Alkaline Silicates

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Giudice

    2007-01-01

    Full Text Available The aim of this paper is to determine the fire performance of wood panels (Araucaria angustifolia impregnated with soluble alkaline silicates. Commercial silicates based on sodium and potassium with 2.5/1.0 and 3.0/1.0 silica/alkali molar ratios were selected; solutions and glasses were previously characterized. Experimental panels were tested in a limiting oxygen chamber and in a two-foot tunnel. Results displayed a high fire-retardant efficiency using some soluble silicates.

  2. Evaluation of High Solids Alkaline Pretreatment of Rice Straw

    OpenAIRE

    Cheng, Yu-Shen; Zheng, Yi; Yu, Chao Wei; Dooley, Todd M.; Jenkins, Bryan M.; VanderGheynst, Jean S.

    2010-01-01

    Fresh-harvested, air-dried rice straw was pretreated at a water content of 5 g H2O/g straw using sodium hydroxide (NaOH) and compared to pretreatment at 10 g H2O/g straw by hydrated lime (Ca(OH)2). Full factorial experiments including parallel wash-only treatments were completed with both sources of alkali. The experiments were designed to measure the effects of alkaline loading and pretreatment time on delignification and sugar yield upon enzymatic hydrolysis. Reaction temperature was held c...

  3. 2011 Alkaline Membrane Fuel Cell Workshop Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Pivovar, B.

    2012-02-01

    A workshop addressing the current state-of-the-art in alkaline membrane fuel cells (AMFCs) was held May 8-9, 2011, at the Crystal Gateway Marriott in Arlington, Virginia. This workshop was the second of its kind, with the first being held December 11-13, 2006, in Phoenix, Arizona. The 2011 workshop and associated workshop report were created to assess the current state of AMFC technology (taking into account recent advances), investigate the performance potential of AMFC systems across all possible power ranges and applications, and identify the key research needs for commercial competitiveness in a variety of areas.

  4. Alkaline cyanide biodegradation by Pseudomonas pseudoalcaligenes CECT5344.

    Science.gov (United States)

    Luque-Almagro, V M; Blasco, R; Huertas, M J; Martínez-Luque, M; Moreno-Vivián, C; Castillo, F; Roldán, M D

    2005-02-01

    Pseudomonas pseudoalcaligenes CECT5344 uses cyanide, cyanate, beta-cyanoalanine, and other cyanoderivatives as nitrogen sources under alkaline conditions, which prevents volatile HCN (pK(a) 9.2) formation. The cyanide consumed by this strain is stoichiometrically converted into ammonium. In addition, this bacterium grows with the heavy metal, cyanide-containing waste water generated by the jewellery industry, and is also a cyanide-resistant strain which induces an alternative oxidase and a siderophore-based mechanism for iron acquisition in the presence of cyanide. The detection of cyanase and beta-cyanoalanine nitrilase activities in cyanide-induced cells suggests their implication in the cyanide degradation pathway.

  5. Koilocytes are enriched for alkaline-labile sites

    Directory of Open Access Journals (Sweden)

    E. I. Cortés-Gutiérrez

    2010-10-01

    Full Text Available This study investigated possible variations in the chromatin structure of koiloc