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Sample records for belt southern west

  1. Field and geochemical characterisitics of the Mesoarchean (~3075 ma) Ivisaartoq greenstone belt, southern West Greenland: Evidence for seafloor hydrothermal alteration in a supra-subduction oceanic crust

    DEFF Research Database (Denmark)

    Polat, A.; Appel, P.W.U.; Frei, Robert;

    2006-01-01

    The Mesoarchean (ca. 3075 Ma) Ivisaartoq greenstone belt in southern West Greenland includes variably deformed and metamorphosed pillow basalts, ultramafic flows (picrites), serpentinized ultramafic rocks, gabbros, sulphide-rich siliceous layers, and minor siliciclastic sedimentary rocks. Primary......-enriched, near-flat HREE, and HFSE (especially Nb)-depleted trace element patterns, indicating a subduction zone geochemical signature. Ultramafic pillows and cumulates display large positive initial eNd values of + 1.3 to + 5.0, consistent with a strongly depleted mantle source. Given the geological...

  2. Intermediate P/T-type regional metamorphism of the Isua Supracrustal Belt, southern west Greenland: The oldest Pacific-type orogenic belt?

    Science.gov (United States)

    Arai, Tatsuyuki; Omori, Soichi; Komiya, Tsuyoshi; Maruyama, Shigenori

    2015-11-01

    The 3.7-3.8 Ga Isua Supracrustal Belt (ISB), southwest Greenland, might be the oldest accretionary complex on Earth. Regional metamorphism of the ISB has a potential to constrain the tectonothermal history of the Earth during the Eoarchean. Chemical and modal analyses of metabasite in the study area (i.e., the northeast part of the ISB) show that the metamorphic grade increases from greenschist facies in the northern part of the study area to amphibolite facies in the southern part. To determine the precise metamorphic P-T ranges, isochemical phase diagrams of minerals of metabasite were made using Perple_X. A synthesis of the estimated metamorphic P-T ranges of the ISB indicates that both the metamorphic pressure and temperature increase systematically to the south in the study area from 3 kbar and 380 °C to 6 kbar and 560 °C. The monotonous metamorphic P-T change suggests that the northeast part of the ISB preserves regional metamorphism resulting from the subduction of an accretionary complex although the ISB experienced metamorphic overprints during the Neoarchean. Both the presence of the regional metamorphism and an accretionary complex having originating at subduction zone suggest that the ISB may be the oldest Pacific-type orogenic belt. The progressive metamorphism can be considered as a record of intermediate-P/T type geothermal gradient at the subduction zone in the Eoarchean. Intermediate-P/T type geothermal gradient is typical at the current zones of subducting young oceanic crust, such as in the case of the Philippine Sea Plate in the southwest part of Japan. Considering the fact that almost all metamorphisms in the Archean are greenschist-amphibolite facies, the intermediate-P/T type geothermal gradient at the ISB might have been worldwide in the Archean. This would indicate that the subduction of young micro-plates was common because of the vigorous convection of hot mantle in the Archean.

  3. The Majorqaq Belt: A record of Neoarchaean orogenesis during final assembly of the North Atlantic Craton, southern West Greenland

    Science.gov (United States)

    Dyck, Brendan; Reno, Barry L.; Kokfelt, Thomas F.

    2015-04-01

    Over the past 4.5 billion years (Ga) the Earth has undergone a secular change in tectonic regimes. Archaean tectonics was a markedly different process than observed today, involving a hotter planet with a thinner lithosphere, thicker oceanic crust, and smaller proto-continents. The transition to a more modern type of plate tectonics required the initiation of subduction of oceanic lithosphere. The onset of subduction in the Meso- to Neoarchaean (ca. 3.2 to 2.5 Ga) is shown by geochemical signatures indicative of crustal recycling and petrologic evidence of tectonically driven thickening of the continental crust. This transition is recorded in the rock record of the North Atlantic Craton, which preserves a history of crust formation through to terrane accretion and the collision of crustal blocks. Here we present petrologic, chronologic, chemical and geophysical evidence from the Majorqaq Belt, a ~ 100 km wide east-west striking zone, defined by a high gravity anomaly, voluminous metasedimentary units, olivine-rich ultramafic enclaves, and anomalously high K2O, Ni, and MgO stream-sediment chemistry. We use a 207Pb/206Pb zircon LA-ICP-MS age of 2.557 ± 0.005 Ga (2σ) from an upper-amphibolite facies metapelitic migmatite to propose Neoarchaean suturing of the Maniitsoq crustal block to the North Atlantic Craton. Ti-in-zircon temperatures and zircon-garnet REE distribution coefficients constrain zircon crystallisation to 815-729 °C, which is at, or near the solidus during leucosome crystallisation. Our data reveal a clockwise P-T path with a high-pressure assemblage of garnet-kyanite-plagioclase-rutile-biotite-quartz which grew at an apparent thermal gradient of ~ 660 °C/GPa during subduction-driven compression of surface-derived sediments to a minimum-peak-pressure of ~ 1.15 GPa at ~ 760 °C followed by the growth of gedrite-cordierite-sillimanite-ilmenite at minimum-peak-temperature conditions of ~ 810 °C at ~ 0.94 GPa. We propose the evolution of the Majorqaq

  4. New investigations in southwestern Guinea: consequences for the Rokelide belt (West Africa)

    Science.gov (United States)

    Villeneuve, Michel; Bellon, Hervé; Corsini, Michel; Le Metour, Joël; Chatelee, Sébastien

    2015-07-01

    The southern Guinean terranes belong to the "Rokelide belt" that is located in the southwestern part of the West African craton (Senegal to Liberia). Field investigations and K-Ar and 40Ar-39Ar radiometric analysis performed on samples collected from southern Guinea provide a new interpretation for metamorphic terranes not yet dated. A K-Ar whole-rock age of a gneiss and 40Ar-39Ar plateau ages of amphiboles separated from a mylonitic gneiss of the Ouankifondi formation and a gneiss from the Kissi-Kissi formation yield several Pan-African metamorphic ages at circa 650, 560, and 530 Ma, respectively. Field investigations show that these formations are unconformably capped by the Kolente group. The previous structural framework and the geodynamic evolution of the Rokelide belt based on the coeval evolution of the Ouankifondi and Kissi-Kissi formations and the Kolente group are reassessed. The Rokelide belt is linked to the Bassaride belt. Correlations with adjacent Sierra Leonean terranes and with northern Guinea and Senegal are considered.

  5. Structural features and petroleum geology of the fold-thrust belt in the southern Tarim basin, China

    Institute of Scientific and Technical Information of China (English)

    ZHOU; Xinyuan; LUO; Jinhai; WANG; Qinghua

    2004-01-01

    The west Kunlun fold-thrust belt (WKFTB) and the Altun fold-thrust belt (AFTB) are respectively located in the southern margin of the Tarim basin, NW China. The analyses of typical structures and regional dynamics of the fold-thrust belts reveal their different structural and petroleum features and mechanisms. WKFTB differs from AFTB by abundant fault-related folds and triangles zones, and was formed by northward extrusion of the west Kunlun orogen. AFTB was affected synchronously by northward extrusion of the Altun orogen and the sinistral strike-slipping of the Altun Fault, so it is characterized by the minor scale and the monotonous structural styles. The Aqike anticline and the Aqike fault, of which the strikes are orthogonal to the strike of the fold-thrust belts, are regarded as the adjustive structures between both of the fold-thrust belts. The oil-gas pools of WKFTB develop mainly in the faulted-related anticline traps, but the oil-gas pools of AFTB develop mainly in the low fault-block and anticlines traps related with the paleo-uplifts. There are different exploration countermeasures for both of the fold-thrust belts.

  6. Cabacal belt, southern Amazon craton in Mato Grosso-Brazil: Implications for the tectonic evolution (more complications)

    International Nuclear Information System (INIS)

    The Amazon Craton covers an area of about 250000Km2 on the northern part of the South America. The Precambrim time history of the craton has been divided in geochronological provinces (Cordani et al. 1979; Teixeira et al. 1989; Tassinari et al. 1996; Tassinari and Macambira, 1999; and Santos et al. 2000). The Cabacal Belt covers an area of approximately 350 square kilometers in the southern region of the Amazon Craton, Mato Grosso-Brazil. It is a narrow NNW trending belt of greenchist to amphibolite grade volcano-sedimentary rocks intruded by plutonic rocks of tonalitic to granitic composition and mafic sills/dikes (Pinho et al., 1997). To the East it is bounded by Mesoproterozoic sediments of the Aguapei Group. To the West it is separated from the Araputanga Belt by a metamorphic complex, chiefly made of orthogneisses. The Cabacal Belt is one of the three NNW trending belts from the Alto Jauru Greenstone Belt. As a whole, the supracrustal rocks of the Cabacal Belt consist of three units: a basal unit comprising mafic lavas and breccias; a middle unit of felsic to intermediate metavolcanics rocks with interlayered tuffs and sediments; and a top unit of dacite-rhyodacit lavas, tuffs, and sediments (clastic and chemical). Monteiro et al. (1986) named these units as Mata Preta (MPF), Manuel Leme (MLF) and Rancho Grande (RGF) formations respectively. Leite et al. (1986) used the name Quatro Meninas Complex for the basic unit We analyzed zircons from seven samples in the Cabacal Belt, including samples from the volcano-sedimentary sequence, from intrusive bodies, and from the gneiss that separates the Cabacal Belt from the Araputanga Belt (au)

  7. The lithospheric mantle below southern West Greenland

    DEFF Research Database (Denmark)

    Sand, Karina Krarup; Waight, Tod Earle; Pearson, D. Graham; Nielsen, Troels F.D.; Makovicky, Emil; Hutchison, Mark T.

    Geothermobarometry of primarily garnet lherzolitic xenoliths from several localities in southern West Greenland is applied to address the diamond potential, pressure and temperature distribution and the stratigraphy of the subcontinental lithospheric mantle ~600 Ma ago. The samples are from...... been conducted. No variation in P-T gradients between the three distinct crustal areas has been discerned. We find that the lithospheric mantle beneath this region extended to a depth of 215 km at the time of eruption, with a geotherm similar to those defined by peridotites from the Slave craton and...... the Kirkland Lake locality within the Superior craton. In supporting previous studies we find that the continental lithospheric mantle is layered and increases in fertility with depth. Twenty-five of 32 investigated samples are estimated to be derived from the diamond stability field that extends into...

  8. Magnetotelluric investigation in and around southern part of Hidaka metamorphic belt in Hokkaido, Japan; Hidaka henseitai nanbuiki ni okeru MT kansoku

    Energy Technology Data Exchange (ETDEWEB)

    Sato, H.; Utsugi, M.; Hirano, K.; Doi, T.; Nishida, Y.; Arita, K. [Hokkaido University, Sapporo (Japan)

    1996-05-01

    An MT observation was conducted in the Hidaka district, Hokkaido, for the estimation of the 2D resistivity structure in the southern part of the metamorphic belt, when frequencies of the VLF, ELF, and ULF bands were used. An approximately 42km-long traverse line was set to cross the Hidaka metamorphic belt from east to west. As for the observation points, 48 VLF points, 16 ELF points, and 4 ULF points were provided. During the data processing, impedance tensor was calculated in the frequency domain for the determination of the apparent resistivity relative to frequency and the phase difference. As the result, it was found that there is a fairly large resistivity gap between observation spots MNS and KWR and that the boundary corresponds to the Hidaka metamorphic belt, that the metamorphic belt that is reflected as a conspicuous high-resistivity layer in the VLF-, ELF-MT slopes down toward the east and has a distribution as deep as 10km in the vicinity of observation point KWR, that this high-resistivity layer sandwiches a low-resistivity layer at a depth of 5-7km, and that on the east side of the metamorphic belt there is a medium-resistivity layer creeping under the belt from the east side toward the west side. 5 refs., 6 figs.

  9. Structural inversion of the Tamworth Belt: Insights into the development of orogenic curvature in the southern New England Orogen, Australia

    Science.gov (United States)

    Phillips, G.; Robinson, J.; Glen, R.; Roberts, J.

    2016-05-01

    The middle to late Permian Hunter Bowen Event is credited with the development of orogenic curvature in the southern New England Orogen, yet contention surrounds the structural dynamics responsible for the development of this curvature. Debate is largely centred on the roles of orogen parallel strike-slip and orogen normal extension and contraction to explain the development of curvature. To evaluate the dynamic history of the Hunter Bowen Event, we present new kinematic reconstructions of the Tamworth Belt. The Tamworth Belt formed as a Carboniferous forearc basin and was subsequently inverted during the Hunter Bowen Event. Kinematic reconstructions of the Tamworth Belt are based on new maps and cross-sections built from a synthesis of best-available mapping, chronostratigraphic data and new interpretations of depth-converted seismic data. The following conclusions are made from our study: (i) the Hunter Bowen Event was dominantly driven by margin normal contraction (east-west shortening; present-day coordinates), and; (ii) variations in structural style along the strike of the Tamworth Belt can be explained by orthogonal vs. oblique inversion, which reflects the angular relationship between the principal shortening vector and continental-arc margin. Given these conclusions, we suggest that curvature around the controversial Manning Bend was influenced by the presence of primary curvature in the continental margin, and that the Hastings Block was translated along a sinistral strike-slip fault system that formed along this oblique (with respect to the regional east-west extension and convergence direction) part of the margin. Given the available temporal data, the translation of the Hastings Block took place in the Early Permian (Asselian) and therefore preceded the Hunter Bowen Event. Accordingly, we suggest that the Hunter Bowen Event was dominantly associated with enhancing curvature that was either primary in origin, or associated with fault block translation

  10. Structure andevolution of the austral basin fold-thrust belt, Southern Patagonian Andes

    Directory of Open Access Journals (Sweden)

    Matías C. Ghiglione

    2009-10-01

    Full Text Available This study focuseson the evolution of the Southern Patagonian Andes fold-thrust belt and theadjacent non-deformed foreland of the Austral basin between 49°45' and52°00'SL. This sector involves mainly Late Cretaceous sequences of the firstregressive cycle (Lago Viedma Cycle of the Austral basin foreland stage, andCampanian to Paleogene sequences associated with tectonic uplift of its westernboundary. From a stratigraphic-sedimentary point of view, a first-orderincrease in the fillthickness and depth to the basement exists from north tosouth including the presence of deeper depositional environments in the samedirection. Furthermore, there are strong along-strike variations in width andlateral position of the structural domains following the same trend. Based uponprevious interpretations, is concluded that the distribution of extensionaldepocenters from the early extensional phase of the basin controlled theseimportant sedimentary and structural N-S contrasts. Furthermore, in ourpresented model, East-west oriented transition zones are interpreted asaccommodation zones separating synrift sub-basins.

  11. Evidences for multiple remagnetization of Proterozoic dykes from Iguerda inlier (Anti-Atlas Belt, Southern Morocco)

    Science.gov (United States)

    Neres, Marta; Silva, Pedro F.; Ikene, Moha; Martins, Sofia; Hafid, Ahmid; Mata, João; Almeida, Francisco; Youbi, Nasrrddine; Boumehdi, Ahmed

    2016-04-01

    Paleomagnetic data able to constrain the paleoposition of the West African Craton (WAC) during Paleo-Mesoproterozoic are absent, mainly due to gaps on the sedimentary record and intense remagnetizations. Dykes that intrude several Proterozoic inliers of WAC in the Anti-Atlas Belt (southern Morocco) have recently been subjected to geochronological studies, which revealed ages between Paleoproterozoic and early Neoproterozoic. Therefore, these dykes represent a window of opportunity for paleomagnetic studies aiming to infer about the paleoposition of WAC during Proterozoic. On this scope we conducted a paleomagnetic study on seven Proterozoic dykes of the Iguerda inlier. We determined the paleomagnetic directions and evaluated their meaning by rock magnetic and mineral analyses, complemented by petrographic observations. Results revealed that these rocks record the presence of a complex history of remagnetization events, mostly assigned to several Phanerozoic thermal/chemical events. In particular, we found components assigned to the late stages of Pan African orogeny (s.l.), to the Late Carboniferous Variscan orogeny, and to more recent events. The recognized remagnetization processes are related to widespread metamorphic events under greenschist facies followed by low-temperature oxidation, both responsible for the formation of new magnetic phases (magnetite and hematite). The primary (magmatic) thermo-remanent magnetization of the dykes was obliterated during these events through multiple thermal and chemical remagnetizations. For only one dyke the presence of primary magnetization is possible to infer, though not to confirm, and would place WAC at an equatorial position around 1750 Ma. The authors wish to acknowledge FCT (Portugal) - CNRST (Morocco) bilateral agreement for its major contribution without which this work wouldn't be possible. Publication supported by project FCT UID/GEO/50019/2013 - Instituto Dom Luiz.

  12. Transpressional deformation, strain partitioning and fold superimposition in the southern Chinese Altai, Central Asian Orogenic Belt

    Science.gov (United States)

    Li, Pengfei; Sun, Min; Rosenbaum, Gideon; Cai, Keda; Chen, Ming; He, Yulin

    2016-06-01

    Transpressional deformation has played an important role in the late Paleozoic evolution of the western Central Asian Orogenic Belt (CAOB), and understanding the structural evolution of such transpressional zones is crucial for tectonic reconstructions. Here we focus on the transpressional Irtysh Shear Zone with an aim at understanding amalgamation processes between the Chinese Altai and the West/East Junggar. We mapped macroscopic fold structures in the southern Chinese Altai and analyzed their relationships with the development of the adjacent Irtysh Shear Zone. Structural observations from these macroscopic folds show evidence for four generations of folding and associated fabrics. The earlier fabric (S1), is locally recognized in low strain areas, and is commonly isoclinally folded by F2 folds that have an axial plane orientation parallel to the dominant fabric (S2). S2 is associated with a shallowly plunging stretching lineation (L2), and defines ∼NW-SE tight-close upright macroscopic folds (F3) with the doubly plunging geometry. F3 folds are superimposed by ∼NNW-SSE gentle F4 folds. The F3 and F4 folds are kinematically compatible with sinistral transpressional deformation along the Irtysh Shear Zone and may represent strain partitioning during deformation. The sub-parallelism of F3 fold axis with the Irtysh Shear Zone may have resulted from strain partitioning associated with simple shear deformation along narrow mylonite zones and pure shear-dominant deformation (F3) in fold zones. The strain partitioning may have become less efficient in the later stage of transpressional deformation, so that a fraction of transcurrent components was partitioned into F4 folds.

  13. Study of the North West Cape electron belts observed by DEMETER satellite

    OpenAIRE

    Li, Xinqiao; Ma, Yuqian; Ping WANG; Wang, Huanyu; Lu, Hong; Zhang, Xuemin; Huang, Jianping; Shi, Feng; Yu, Xiaoxia; Xu, Yanbing; Meng, Xiangcheng; Wang, Hui; Zhao, Xiaoyun; Parrot, Michel

    2012-01-01

    [1] We analyzed observation data collected by the Instrument for the Detection of Particles (IDP) on board the DEMETER satellite during a period of 17 months in 2007 and 2008. In the meantime, the VLF transmitter located at North West Cape (NWC) ground station was shut down during 7 months and working for a total of 10 months. By an (on-off) method, our analysis for the first time revealed in detail the transient properties of the space electron precipitation belt which is induced by the man-...

  14. Paleomagnetic constraints for the tectonic evolution of the southern Apennines belt (Italy)

    OpenAIRE

    Gattacceca, J.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Speranza, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia

    2007-01-01

    The southern Apennine belt is formed by nappes that have undergone large (i. e. hundreds of kms) horizontal displacements. In such tectonic scenario, orogenic rotations of nappes are clearly expected, and paleomagnetism may represent a key tool to constrain displacements and understand the pre-orogenic paleogeography. Recent paleomagnetic data have shown that the Apenninic carbonate platform, on top of the nappe pile, has rotated ~80° counterclockwise (CCW) after Langhian...

  15. Paleoproterozoic Greenstone-Granite Belts in Northern Brazil and the Former Guyana Shield - West African Craton Province

    Directory of Open Access Journals (Sweden)

    Ian McReath

    2006-03-01

    Full Text Available The mainly meta-volcano-sedimentary Vila Nova Group and associated granites constitute separate belts, which formpart of a large paleoproterozoic (mainly rhyacian province in the Guyana Shield of which northern Brazil forms a part, andthe West African Craton. In Brazil the southwestern Serra do Ipitinga and Serra Tumucumaque-Serra do Navio belts have noobvious geometrical extensions in the Guyanas or Venezuela, and may represent deposits formed at penecontemporaneouspassive continental margins and ocean floor spreading centres. To the Northeast the Serra Lombarda-Tartarugalzinho andOiapoque belts are continuations of Guianese belts. In the former the igneous rocks have geochemical characteristics ofsuprasubduction environments. Belts in the Guyana Shield and West African Craton have many similar features. Themegaprovince evolved in a number of stages, which may have started at about 2.3 Ga, and continued with diminished activityafter 2.11 Ga. Both major juvenile additions and (possibly minor reworking of earlier crust contributed to the growth of theprovince. The major transcurrent deformation, responsible for the present structure of the belts, probably occurred duringthe later stages of evolution of the province, but metamorphism and deformation are registered even in the oldest rocks.

  16. Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt

    Science.gov (United States)

    Rosengard, S. Z.; Lam, P. J.; Balch, W. M.; Auro, M. E.; Pike, S.; Drapeau, D.; Bowler, B.

    2015-07-01

    Sequestration of carbon by the marine biological pump depends on the processes that alter, remineralize, and preserve particulate organic carbon (POC) during transit to the deep ocean. Here, we present data collected from the Great Calcite Belt, a calcite-rich band across the Southern Ocean surface, to compare the transformation of POC in the euphotic and mesopelagic zones of the water column. The 234Th-derived export fluxes and size-fractionated concentrations of POC, particulate inorganic carbon (PIC), and biogenic silica (BSi) were measured from the upper 1000 m of 27 stations across the Atlantic and Indian sectors of the Great Calcite Belt. POC export out of the euphotic zone was correlated with BSi export. PIC export was not, but did correlate positively with POC flux transfer efficiency. Moreover, regions of high BSi concentrations, which corresponded to regions with proportionally larger particles, exhibited higher attenuation of > 51 μm POC concentrations in the mesopelagic zone. The interplay among POC size partitioning, mineral composition, and POC attenuation suggests a more fundamental driver of POC transfer through both depth regimes in the Great Calcite Belt. In particular, we argue that diatom-rich communities produce large and labile POC aggregates, which not only generate high export fluxes but also drive more remineralization in the mesopelagic zone. We observe the opposite in communities with smaller calcifying phytoplankton, such as coccolithophores. We hypothesize that these differences are influenced by inherent differences in the lability of POC exported by different phytoplankton communities.

  17. Exhalative Lead-Zinc Deposits in Shallow Sea, Southern Xicheng Belt, Gansu Province

    Institute of Scientific and Technical Information of China (English)

    ZHU Xinyou; WANG Dongbo; WEI Zhiguo; QIU Xiaoping; WANG Ruiting

    2008-01-01

    SEDEX-type lead-zinc deposits in the southern belt of the Xicheng Devonian basin, GansuProvince has been already identified. However, the sedimentary environment of the limestone andphilite of the Xihanshui Group within which the lead-zinc deposits occur is littoral and shallow sea.This is different from those in the northern belt such as the Changba-Lijiagou lead-zinc deposits, whichwere formed in deep sea. The reef and bioclastic limestone are widespread in the southern belt.Particularly they are associated with lead-zinc ores and there are no striae and banding but massive ordisseminated structures. It is discovered that the black chimney consists of sphalerite, ankerite, pyriteand galena, in which black, coarse and radial sphalerite occurs as irregularly veins or cylindricafitywith a width of 10-40 cm in the center, and it is surround by fine ankerite and minor celestite withribbon structure. The immediate wall rock of the chimney, reef limestone, was unaltered and theoutside reef and bioclastic limestone were intensively silicified. Those silicified reef and bioclasticlimestone host disseminated lead-zinc ores of the Lnoba and Bijiashan type. It is concluded that theexhalative system occurred in a shallow sea in the Givetian of the middle Devonian. Brine is boiled dueto low pressure, and a great deal of lead and zinc was dispersed in the interface between the limestoneand phyllite and formed a source bed. In the Triassic period, meta-hydrothermai fluids leached andextracted metals from the source bed, and then moved and mineralized in open space such as archesand inverse limbs of anticlines, and formed massive and vein ores such as the Jianyagou andDengjiashan type deposits.

  18. Centennial-scale shifts in the position of the Southern Hemisphere westerly wind belt over the past millennium

    Directory of Open Access Journals (Sweden)

    B. G. Koffman

    2013-06-01

    Full Text Available We present the first high-resolution (sub-annual dust particle dataset from West Antarctica, developed from the West Antarctic Ice Sheet (WAIS Divide deep ice core (79.468° S, 112.086° W, and use it to reconstruct past atmospheric circulation. We find a background dust flux of ∼4 mg m−2 yr−1 and a mode particle size of 5–8 μm diameter. Through comparison with other Antarctic ice core particle records, we observe that coastal and lower-elevation sites have higher dust fluxes and coarser particle size distributions (PSDs than sites on the East Antarctic plateau, suggesting input from local dust sources at lower elevations and sites closer to the coast. In order to explore the use of the WAIS Divide dust PSD as a proxy for past atmospheric circulation, we make quantitative comparisons between mid-latitude zonal wind speed and the dust size (coarse particle percentage, CPP record, finding significant positive interannual relationships. Using our CPP record, and through comparison with spatially distributed climate reconstructions from the Southern Hemisphere (SH middle and high latitudes, we infer latitudinal shifts in the position of the SH westerly wind belt during the Medieval Climate Anomaly (MCA; ∼950–1350 C.E. and Little Ice Age (LIA; ∼1400–1850 C.E. climate intervals. We suggest that the SH westerlies occupied a more southerly position during the MCA, and shifted equatorward at the onset of the LIA (∼ 1430 C.E. due to cooler surface temperatures and a contraction of the SH Hadley cell.

  19. The JCMT Gould Belt Survey: A First Look at Southern Orion A with SCUBA-2

    CERN Document Server

    Mairs, Steve; Kirk, H; Buckle, J; Berry, D S; Broekhoven-Fiene, H; Currie, M J; Fich, M; Graves, S; Hatchell, J; Jenness, T; Mottram, J C; Nutter, D; Pattle, K; Pineda, J E; Salji, C; Di Francesco, J; Hogerheijde, M R; Ward-Thompson, D; Bastien, P; Bresnahan, D; Butner, H; Chen, M; Chrysostomou, A; Coudé, S; Davis, C J; Drabek-Maunder, E; Duarte-Cabral, A; Fiege, J; Friberg, P; Friesen, R; Fuller, G A; Greaves, J; Gregson, J; Holland, W; Joncas, G; Kirk, J M; Knee, L B G; Marsh, K; Matthews, B C; Moriarty-Schieven, G; Mowat, C; Rawlings, J; Richer, J; Robertson, D; Rosolowsky, E; Rumble, D; Sadavoy, S; Thomas, H; Tothill, N; Viti, S; White, G J; Wouterloot, J; Yates, J; Zhu, M

    2016-01-01

    We present the JCMT Gould Belt Survey's first look results of the southern extent of the Orion A Molecular Cloud ($\\delta \\leq -5\\mathrm{:}31\\mathrm{:}27.5$). Employing a two-step structure identification process, we construct individual catalogues for large-scale regions of significant emission labelled as islands and smaller-scale subregions called fragments using the 850 $\\mu$m continuum maps obtained using SCUBA-2. We calculate object masses, sizes, column densities, and concentrations. We discuss fragmentation in terms of a Jeans instability analysis and highlight interesting structures as candidates for follow-up studies. Furthermore, we associate the detected emission with young stellar objects (YSOs) identified by Spitzer and Herschel. We find that although the population of active star-forming regions contains a wide variety of sizes and morphologies, there is a strong positive correlation between the concentration of an emission region and its calculated Jeans instability. There are, however, a numb...

  20. Evolution of the Bhandara-Balaghat granulite belt along the southern margin of the Sausar Mobile Belt of central India

    Indian Academy of Sciences (India)

    H M Ramachandra; Abhinaba Roy

    2001-12-01

    The Bhandara-Balaghat granulite (BBG) belt occurs as a 190 km long, detached narrow, linear, NE-SW to ENE-WSW trending belt that is in tectonic contact on its northern margin with the Sausar Group of rocks and is bordered by the Sakoli fold belt in the south. The Bhandara part of the BBG belt is quite restricted, comprising a medium to coarse grained two-pyroxene granulite body that is of gabbroic composition and preserves relic igneous fabric. The main part of the belt in Arjuni-Balaghat section includes metasedimentary (quartzite, BIF, Al- and Mg-Al metapelites) and metaigneous (metaultramafic, amphibolite and two-pyroxene granulite) protoliths interbanded with charnockite and charnockitic gneiss. These rocks, occurring as small bands and enclaves within migmatitic and granitic gneisses, show polyphase deformation and metamorphism. Geochemically, basic compositions show tholeiitic trend without Fe-enrichment, non-komatitic nature, continental affinity and show evolved nature. Mineral parageneses and reaction textures in different rock compositions indicate early prograde, dehydration melt forming reactions followed by orthopyroxene stability with or without melt. Coronitic and symplectitic garnets have formed over earlier minerals indicating onset of retrograde IBC path. Evidences for high temperature ductile shearing are preserved at places. Retrogressive hydration events clearly post-date the above paths. The present study has shown that the BBG belt may form a part of the Bastar Craton and does not represent exhumed oceanic crust of the Bundelkhand Craton. It is further shown that rocks of the BBG belt have undergone an earlier high-grade granulite metamorphism at 2672 ± 54 Ma (Sm-Nd age) and a post-peak granulite metamorphism at 1416 ± 59 Ma (Sm-Nd age, 1380 ± 28 Ma Rb-Sr age). These events were followed by deposition of the Sausar supracrustals and Neoproterozoic Sausar orogeny between 973 ± 63 Ma and 800 ± 16 Ma (Rb-Sr ages).

  1. On the upwelling off the Southern Tip and along the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Smitha, B.R.; Sanjeevan, V.N.; VimalKumar, K.G.; Revichandran, C.

    The processes of upwelling off the southern tip (the Kanyakumari coast) and the west coast of India are highly localized features with different forcing mechanisms, and they cannot be treated as a uniform wind-driven upwelling system. Off...

  2. Geomorphic signature of active tectonics in the southern Abruzzi Periadriatic hilly belt (Central Italy)

    Science.gov (United States)

    Racano, Simone; Fubelli, Giandomenico; Centamore, Ernesto; Dramis, Francesco

    2016-04-01

    The geo-structural setting of the southern Abruzzi hilly belt that stretches from the northeastern front of the Maiella Massif to the Adriatic coast is characterized by deep-seated northeast verging thrusts masked by a thick cover of Late Pliocene-Middle Pleistocene marine deposits. Most authors consider this area tectonically inactive while only few of them support the hypothesis of its recent activity from the analysis of the river network pattern. Geological and geomorphological investigations carried out in the area have clearly shown the occurrence of surface deformations resulting from the continued activity of compressive tectonics up to recent times. The analysis of the study area by of a 10 m resolution DTM (using the open-source QGIS software) confirmed and supplemented field observations. Particularly significant in this context is the topographic setting of the alluvial strath terraces in the river valleys that develop transversally to the buried thrusts. In correspondence of these structures, topographic highs have grown up displacing the middle-Pleistocene planation surface developed on top of the hilly belt, from the Maiella piedmont to the coastal zone, and diverting laterally the river courses uphill. In the same places, as along the Alento and Foro rivers that cross by antecedence the grown up topographic highs, the long profiles of terraces bend eastward and the height difference between the terrace orders, essentially related all around the area to the Quaternary regional uplift, strongly increases. In some cases, surficial faults have lowered the terraces into graben troughs or have displaced them until assuming an uphill trend. This recent tectonic activity should be taken in account in assessing the seismic hazard of the study area.

  3. Study on Capability of Power Transmission from West to East in China Southern Power Grid

    Institute of Scientific and Technical Information of China (English)

    Li Wei; Tong Mingdong; Zhang Lin; Xu Dongjie; Lin Feng; Li Xin; Zuo Zhengmin

    2007-01-01

    @@ The uneven distribution of economic development and energy resources in the Southern Power Grid, yet with stronger complementary superiority has determined the necessity to actively push forward power transmission from west to east in the Southern Power Grid and realize optimal disposition in even greater scope. To further promote transmission capability and operational security from west to east, measures including power sources disposition, unit starting schemes, power grid configuration, DC modulation and application of new transmission technologies are analyzed in this paper.

  4. Late Holocene activity and historical earthquakes of the Qiongxi thrust fault system in the southern Longmen Shan fold-and-thrust belt, eastern Tibetan Plateau

    Science.gov (United States)

    Wang, Maomao; Jia, Dong; Lin, Aiming; Shen, Li; Rao, Gang; Li, Yiquan

    2013-01-01

    The 12 May 2008 Wenchuan earthquake (Mw 7.9) generated a 285-km-long surface rupture zone along the Longmen Shan fold-and-thrust belt (LSFTB) on the eastern margin of Tibetan Plateau. The Wenchuan earthquake did not rupture into the southwestern Longmen Shan, along which there is no evidence for large paleo- or historical earthquakes. Seismic reflection profiles and field investigations reveal that the 50-km-long Qiongxi thrust fault (QTF) of the southern LSFTB is currently active. The QTF consists of three west-dipping ramp segments overlain by fault-bend folds rooted in a regional detachment that transfers shortening from the mountain belt into the Sichuan basin. Trench investigations, coupled with interpretations of seismic reflection profiles and radiocarbon results, show that a recent surface-rupturing earthquake occurred on the QTF during the Late Ming to Qing Dynasty, between AD 1600 and 1800. In addition, seismic reflection profile and topographic analysis indicate the presence of a subtle topographic, produced by kink-band migration folding above a fault bend at about 5 km depth. These findings confirm that the QTF is a significant seismic hazard, and that it should be incorporated into current regional seismic hazard models for the densely populated Sichuan basin.

  5. The Variscan belt of Northern France Southern Belgium: geodynamic implications of new palaeomagnetic data

    Science.gov (United States)

    Márton, Emő; Mansy, Jean-Louis; Averbuch, Olivier; Csontos, László

    2000-09-01

    Palaeomagnetic investigations were carried out in Devonian-early Carboniferous rocks of the Variscan foreland chain of Northern France-Southern Belgium in order to reveal the origin of its arcuate shape. The Brabant Parautochthon was sampled in the Boulonnais (near Calais) and near Tournai, while the Ardenne Allochthon was sampled near Maubeuge and in the Givet area. All the sampled localities yielded characteristic remanent magnetization as a result of stepwise demagnetization and component analysis. Fold or tilt tests were possible for three localities, with negative results indicating pervasive remagnetization. The tectonic position was sub-horizontal at two localities, while the tilt was monoclinal for the rest. Therefore, the acquisition time of the magnetic signals was estimated by comparing the palaeolatitude computed from each magnetic component to the palaeolatitudes of Variscan Europe calculated after Van der Voo (1993). Three components showing: A, a southern B, a near-Equatorial, and C, a northern palaeolatitude are recognized from our data. Since a pre-Variscan age of component A (observed only in Boulonnais, at 10 sites) is not supported by data, it is assigned to an early phase of deformation. Component B (16 sites) was acquired during the peak of the Variscan tectonics (late Westphalian), while component C (five sites) originated during Permian times. Regardless of the palaeolatitudes, declinations fall between 190 and 210°, thus being conformable with the declinations expected for Variscan Europe. The declinations show no correlation with the arcuate shape of the belt, neither are they different in the Paraauthochthon and in the Allochthon, nor in the different components. Arc formation by moulding of the Allochthon on the Brabant Parautochthon is, therefore, not supported by these data, since this mechanism requires substantial (opposed) rotations on both wings of the arc. The available palaeomagnetic data are conformable with a pre-formed arc

  6. FOOD SAFETY PERCEPTIONS AND BEHAVIOR OF CONSUMERS IN THE SOUTHERN BLACK BELT OF THE U.S.

    OpenAIRE

    Adu-Nyako, Kofi; Thompson, Alton

    1999-01-01

    A new data set is used to study differences in the food safety perceptions and behavior of black and white consumers in the Southern Black Belt of the US. Analysis of general food safety risk perceptions and ethnic origin indicate no significant differences in the perceptions of blacks and whites. Further, the issue of 'misperception' by consumers of the origin of most foodborne illness is not explained by sociodemograhic factors but rather consumers information sources and awareness of foodb...

  7. The southern Araçuaí belt and the Dom Silvério Group: geologic architecture and tectonic significance

    Directory of Open Access Journals (Sweden)

    Guilherme G. Peres

    2004-12-01

    Full Text Available The Araçuaí belt corresponds to the external portion of the western half of the Araçuaí-West Congo Neopro-terozoic orogen. TheAraçuaí belt fringes the São Francisco craton to east and is separated from the crystalline core of the orogen by the Abre Campo geophysical discontinuity. The southern Araçuaí belt involves four major lithologic units: the Archean and Paleoproterozoic gneisses of the Mantiqueira Complex, the Pedra Dourada Charnockite, the Paleoproterozoic Borrachudos Granitoid, and the metavolcanosedimentary rocks of the Dom Silvério Group. The Dom Silvério Group occurs in a NNE-SSW striking belt and consists of a thick package of metapelitic rocks with intercalations of quartzites, amphibolites, meta-ultramafics, banded iron formations, gondites and marbles. All units of the southern Araçuaí belt underwent four syn-metamorphic phases of deformation in the course of the Brasiliano event. The first phase, synchronous to a regional amphibolite facies metamorphism, was associated to a general tectonic transport towards north along the left-lateral Dom Silvério shear zone and its low angle segment. The second and third phases represent progressive stages of a west directed shortening, which led to the development of local thrusts and pervasive folds in several scales. The fourth phase is extensional and reflects the collapse of the orogen.A Faixa Araçuaí corresponde à porção ocidental externa do orógeno neoproterozóico Araçuaí-Congo Ocidental. Margeia a borda leste do Cráton do São Francisco e é separada do núcleo cristalino do orógeno pela descontinuidade geofísica de Abre Campo. A porção meridional da Faixa Araçuaí envolve quatro unidades litológicas principais: os ortognaisses arqueanos e paleoproterozóicos do Complexo Mantiqueira, os charnoquitos Pedra Dourada, os granitóides paleoproterozóicos da Suíte Borrachudos e as rochas metavulcanossedimentares do Grupo Dom Silvério. O Grupo Dom Silv

  8. PETROGENETIC AND METALLOGENETIC AGES FOR THE PORPHYRY COPPER DEPOSITS IN THE GANGDISE METALLOGENIC BELT IN SOUTHERN TIBET

    Institute of Scientific and Technical Information of China (English)

    LI Guangming; RUI Zongyao

    2004-01-01

    Recent examination and assessment about the porphyry copper deposits in Gangdise metallogenic belt in southern Tibet have revealed that these porphyry copper deposits are highly prospective. Several methods have been used for the isotopic dating of the Qulong, Tinggong and Chongjiang porphyry copper deposits, which gives out a petrogenetic age of 17.58±0.74Ma (single-zircon dating of SHRIMP), a metallogenetic age of 15.99±0.32Ma (Re-Os isochron dating) and an alteration age ranging between12.00Ma and 16.5Ma (K-Ar dating). The metallogenetic age is in general agreement with the alteration age.It can be seen that the petrogenetic and metallogenetic ages for the porphyry copper deposits in Gangdise metallogenic belt are noticeably later than the age for the collisional granitic intrusion in this belt. The authors contend that the porphyry copper deposits in the study area were formed in a post-collisional extensional tectonic setting, and are closely related to the delamination of the mountain roots of the orogenic belts and the uplifting of the Qinghai-Tibet Plateau.

  9. West Nile Virus Antibody Prevalence in Wild Mammals, Southern Wisconsin

    OpenAIRE

    Docherty, Douglas E.; Samuel, Michael D.; Nolden, Cherrie A.; Egstad, Kristina F.; Griffin, Kathryn M.

    2006-01-01

    Twenty percent prevalence of West Nile virus antibody was found in free-ranging medium-sized Wisconsin mammals. No significant differences were noted in antibody prevalence with regard to sex, age, month of collection, or species. Our results suggest a similar route of infection in these mammals.

  10. Metamorphism and gold mineralization of the Kenticha Katawicha area: Adola belt, southern Ethiopia

    Science.gov (United States)

    Tsige, Lulu

    2006-05-01

    I present geological and mineral chemistry results aiming at understanding the relationship between metamorphism and gold mineralization in the N-trending Neoproterozoic Kenticha-Katawicha area in the Adola belt of southern Ethiopia. The Kenticha-Katawicha area comprises low-grade metamorphic rocks including pelitic schists, marble, graphite schists and Fe-Mn quartzites (Kenticha marine metasedimentary rocks) and serpentinites and talc-tremolite-chlorite schists with podiform chromites (Kenticha ophiolite). Lenses of high-grade amphibolite schist are also locally present within the Kenticha-Katawicha area. These rocks are sandwiched between high-grade para- and ortho-gneisses, migmatites, schists and amphibolites. Post-orogenic granites intrude the metamorphic sequences. Mineral assemblages and textural data obtained from the high-grade rocks indicate that the dominant metamorphic condition is of upper amphibolite facies. Garnet-biotite (garnet-core-matrix-biotite) and amphibole-plagioclase geothermometry gave estimates for peak metamorphic temperatures of 630-650 °C and pressure of 7 kbar for the high-grade rocks. On the other hand, the low-grade rocks recrystallized in the greenschist facies conditions. The estimated peak T- P values for the high-grade rocks suggest a burial to ˜25 km depth and a clockwise P- T path is deduced from mineral thermometry and the textural and paragenetic relations. This combined with the geochemistry of the magmatic rocks and clockwise P- T is consistent with a collision setting in which rocks of the calc-alkaline, volcanic-arc, and oceanic fragments are assembled. In the study area, gold occurs in quartz veins and veinlets in lenses of biotite schists within ultramafic rocks that are confined to shear zones. Fluid inclusion studies of gold quartz veins and veinlets indicate a H 2O- and CO 2-rich fluid with low salinity (<5 wt% NaCl equivalent). The gold mineralization in the area is post-peak regional metamorphism and is

  11. 75 FR 32839 - Norfolk Southern Railway Company-Trackage Rights Exemption-The West Tennessee Railroad, LLC

    Science.gov (United States)

    2010-06-09

    ... Surface Transportation Board Norfolk Southern Railway Company--Trackage Rights Exemption--The West Tennessee Railroad, LLC Pursuant to a written trackage rights agreement, The West Tennessee Railroad, LLC (WTNN) has agreed to grant overhead trackage rights to Norfolk Southern Railway Company (NSR) \\1\\...

  12. Suspended particulate layers and internal waves over the southern Monterey Bay continental shelf: an important control on shelf mud belts?

    Science.gov (United States)

    Cheriton, Olivia M.; McPhee-Shaw, Erika E.; Shaw, William J.; Stanton, Timothy P.; Bellingham, James G.; Storlazzi, Curt D.

    2014-01-01

    Physical and optical measurements taken over the mud belt on the southern continental shelf of Monterey Bay, California documented the frequent occurrence of suspended particulate matter features, the majority of which were detached from the seafloor, centered 9–33 m above the bed. In fall 2011, an automated profiling mooring and fixed instrumentation, including a thermistor chain and upward-looking acoustic Doppler current profiler, were deployed at 70 m depth for 5 weeks, and from 12 to 16 October a long-range autonomous underwater vehicle performed across-shelf transects. Individual SPM events were uncorrelated with local bed shear stress caused by surface waves and bottom currents. Nearly half of all observed SPM layers occurred during 1 week of the study, 9–16 October 2011, and were advected past the fixed profiling mooring by the onshore phase of semidiurnal internal tide bottom currents. At the start of the 9–16 October period, we observed intense near-bed vertical velocities capable of lifting particulates into the middle of the water column. This “updraft” event appears to have been associated with nonlinear adjustment of high-amplitude internal tides over the mid and outer shelf. These findings suggest that nonlinear internal tidal motions can erode material over the outer shelf and that, once suspended, this SPM can then be transported shoreward to the middle and shallow sections of the mud belt. This represents a fundamental broadening of our understanding of how shelf mud belts may be built up and sustained.

  13. Suspended particulate layers and internal waves over the southern Monterey Bay continental shelf: An important control on shelf mud belts?

    Science.gov (United States)

    Cheriton, Olivia M.; McPhee-Shaw, Erika E.; Shaw, William J.; Stanton, Timothy P.; Bellingham, James G.; Storlazzi, Curt D.

    2014-01-01

    Physical and optical measurements taken over the mud belt on the southern continental shelf of Monterey Bay, California documented the frequent occurrence of suspended particulate matter features, the majority of which were detached from the seafloor, centered 9-33 m above the bed. In fall 2011, an automated profiling mooring and fixed instrumentation, including a thermistor chain and upward-looking acoustic Doppler current profiler, were deployed at 70 m depth for 5 weeks, and from 12 to 16 October a long-range autonomous underwater vehicle performed across-shelf transects. Individual SPM events were uncorrelated with local bed shear stress caused by surface waves and bottom currents. Nearly half of all observed SPM layers occurred during 1 week of the study, 9-16 October 2011, and were advected past the fixed profiling mooring by the onshore phase of semidiurnal internal tide bottom currents. At the start of the 9-16 October period, we observed intense near-bed vertical velocities capable of lifting particulates into the middle of the water column. This "updraft" event appears to have been associated with nonlinear adjustment of high-amplitude internal tides over the mid and outer shelf. These findings suggest that nonlinear internal tidal motions can erode material over the outer shelf and that, once suspended, this SPM can then be transported shoreward to the middle and shallow sections of the mud belt. This represents a fundamental broadening of our understanding of how shelf mud belts may be built up and sustained.

  14. Structural and geochemical mapping of a Fe-mineralized quartz-mica rich unit in the Ringvassøya Greenstone Belt, West Troms Basement Complex

    OpenAIRE

    Elvenes, Hallgeir

    2015-01-01

    Ringvassøy is one of a chain of large coastal islands representing the Archaean to Paleoproterozoic West Troms Basement Complex (WTBC), west of the Caledonides. On Ringvassøy, a basement of mainly tonalitic gneiss is overlain by the Ringvassøy Greenstone Belt (RGB), which is metamorphosed up to middle amphibolite facies. Tonalitic gneiss in the west and southeast of the island has U–Pb zircon ages of 2.84–2.82 Ga, similar to U–Pb zircon ages of 2.85–2.83 Ga for metavolcanics in the RGB. Mafic...

  15. Geologic Controls of Hydrocarbon Occurrence in the Southern Appalachian Basin in Eastern Tennessee, Southwestern Virginia, Eastern Kentucky, and Southern West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Robert D. Hatcher

    2004-05-31

    This report summarizes the second-year accomplishments of a three-year program to investigate the geologic controls of hydrocarbon occurrence in the southern Appalachian basin in eastern Tennessee, southwestern Virginia, eastern Kentucky, and southern West Virginia. The project: (1) employs the petroleum system approach to understand the geologic controls of hydrocarbons; (2) attempts to characterize the T-P parameters driving petroleum evolution; (3) attempts to obtain more quantitative definitions of reservoir architecture and identify new traps; (4) is working with USGS and industry partners to develop new play concepts and geophysical log standards for subsurface correlation; and (5) is geochemically characterizing the hydrocarbons (cooperatively with USGS). Second-year results include: All current milestones have been met and other components of the project have been functioning in parallel toward satisfaction of year-3 milestones. We also have been effecting the ultimate goal of the project in the dissemination of information through presentations at professional meetings, convening a major workshop in August 2003, and the publication of results. Our work in geophysical log correlation in the Middle Ordovician units is bearing fruit in recognition that the criteria developed locally in Tennessee and southern Kentucky have much greater extensibility than anticipated earlier. We have identified a major 60 mi-long structure in the western part of the Valley and Ridge thrust belt that is generating considerable exploration interest. If this structure is productive, it will be one of the largest structures in the Appalachians. We are completing a more quantitative structural reconstruction of the Valley and Ridge than has been made before. This should yield major dividends in future exploration in the southern Appalachian basin. Our work in mapping, retrodeformation, and modeling of the Sevier basin is a major component of the understanding of the Ordovician

  16. Eocene slab breakoff of Neotethys as suggested by dioritic dykes in the Gangdese magmatic belt, southern Tibet

    Science.gov (United States)

    Ma, Xuxuan; Xu, Zhiqin; Meert, Joseph G.

    2016-04-01

    The Gangdese magmatic belt in southern Tibet demarcates an important boundary between the Indian and Eurasian plates. Due to its location and magmatic evolutionary history, it is key to understanding both the history of Neotethys closure and the Indo-Asian collisional process. This study presents new geochronological and geochemical data for dioritic dykes in the southern Gangdese magmatic belt in southern Tibet. U-Pb geochronological results reveal that the dykes were emplaced at ca. 41 Ma and thus broadly coeval with the 40-38 Ma Dazi volcanics and the 42-40 Ma Gaoligong-Tengliang basaltic dykes. Geochemically, these dykes are characterized by alkaline signature, high Mg# (57-63) and low TiO2 contents (~ 0.9-1.0), showing notable enrichment of light rare earth elements relative to the heavy rare earth elements, enrichment of incompatible elements (i.e. Cs, Rb, Ba, Th and U), and depletion of high field strength elements (i.e. Nb, Ta and Ti). In addition, a large variation of zircon εHf(t) values (- 10 to + 13) was shown, implying heterogeneity of magma sources. A heterogeneous source is also suggested by the occurrence of xenocrysts in the dykes. These observations suggest that the magma source of the dykes was dominated by partial melting of lithospheric mantle and then subsequently contaminated by crustal material during ascent. In combination with other geological data in the region, we suspect that the slab slicing of the Neotethys played a key role in the formation of the lithospheric mantle-derived dioritic dykes and adakitic granite, asthenosphere-derived volcanics, basaltic dykes, as well as the recently reported strongly fractionated granites.

  17. Geology, mineralogy and geochemistry of the Holmsletfjella Au-As occurrence, West Spitsbergen Fold Belt, Svalbard

    OpenAIRE

    Simonsen, Håvard Kvåle

    2012-01-01

    Holmsletfjella is situated on the southern side of St. Jonsfjorden on the archipelago of Svalbard. The drill core herein studied is part of an exploration program by Store Norske. Chemical analysis of the drill cores in combination with the geological history have reviled the Holmsletfjella Formation and the Ultramafic Vestgötabreen Complex to have been altered by fluids migrating through the rocks during the formation of the Caledonian mountain chain. These fluids were sourced from VAMSNAZ (...

  18. Tectonic evolution of the Brusque Group, Dom Feliciano belt, Santa Catarina, Southern Brazil

    Science.gov (United States)

    Basei, M. A. S.; Campos Neto, M. C.; Castro, N. A.; Nutman, A. P.; Wemmer, K.; Yamamoto, M. T.; Hueck, M.; Osako, L.; Siga, O.; Passarelli, C. R.

    2011-12-01

    The Dom Feliciano Belt constitutes the main geotectonic unit of the southeastern portion of Brazil and Uruguay. It was formed by the end of the Neoproterozoic as a result of the interaction among the Rio de La Plata, Paranapanema, Congo and Kalahari cratons during the formation of Western Gondwana. The Brusque Group represents the supracrustal units of the Dom Feliciano Belt that occur in its northernmost part, which ends in the Brazilian coast and probable continuity in the Kaoko Belt in southwestern Africa. It is possible to constrain the evolution of the Brusque Group paleobasin to the Neoproterozoic, with the rift phase starting in the Tonian (940-840 Ma) and the main sedimentation occurring until 640 Ma, as indicated by the ages of the acid volcanic rocks intercalated with the metasedimentary sequence. The supracrustal rocks can be grouped in three main units lithostratigraphically organized from the oldest to the youngest: Rio Oliveira Formation (rift phase, predominating metavolcanic units), Botuverá Formation (metasedimentary) and Rio da Areia Formation (metavolcano-carbonatic). Between 640 and 600 Ma several metamorphism and deformation phases affected the Brusque Group. Around 600 ± 10 Ma the three granitic suites (São João Batista, Valsungana and Nova Trento) were emplaced within regional metamorphites, producing post-foliation S2 metamorphic aureoles. S2 represents the main foliation observed in the metavolcanosedimentary rocks that constitute the Brusque Group. The tectonic model for the evolution of Brusque Group can be better achieved only when the geochemical, isotopic and geochronologic information available for the Dom Feliciano Belt in Santa Catarina, is considered as a whole. Therefore it is here suggested that the Brusque Group initially evolved in an independent peri-cratonic basin setting separated from the Florianópolis - Pelotas-Aiguá magmatic arc by the Adamastor ocean, having been juxtaposed to it only around 600 Ma, when Brusque

  19. Qualitative and semiquantitative interpretation of aeromagnetic data over the Lancinha Shear Zone, Southern Ribeira Belt, in Paraná State, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Luís Gustavo de Castro

    2014-12-01

    Full Text Available The characterization of shear zones at the southern portion of the Ribeira Belt, PR, BR, as well as its recognition in depth is a major challenge. Despite the lack of subsurface information, the influence of such structures on the installation and evolution of the Paraná Basin during the Phanerozoic is widely accepted. Therefore, in this paper, are applied methods of anomaly enhancement (qualitative analysis and estimative of the sources depth (semiquantitative analysis, on the aeromagnetic coverage of the Lancinha Shear Zone area (LSZ in the Paraná state, in order to verify its spatial arrangement in subsurface. The processing resulted in the interpretation of magnetic-structural framework of the study area, which was validated by the depth estimative of the magnetic sources (Euler solutions. The results indicated the extension of the Lancinha, Morro Agudo and Itapirapuã shear zones under the Paraná Basin coverage.

  20. Importance of Wetlands Management for West Nile Virus Circulation Risk, Camargue, Southern France

    OpenAIRE

    Sophie Pradier; Alain Sandoz; Paul, Mathilde C; Gaëtan Lefebvre; Annelise Tran; Josiane Maingault; Sylvie Lecollinet; Agnès Leblond

    2014-01-01

    To assess environmental and horse-level risk factors associated with West Nile Virus (WNV) circulation in Camargue, Southern France, a serosurvey was conducted on non-vaccinated horses (n = 1159 from 134 stables) in 2007 and 2008. Fifteen Landsat images were examined to quantify areas with open water and flooded vegetation around sampled horses. Mean percentages of areas of open water and flooded vegetation, as well as variations in these percentages between 3 periods (November to Februar...

  1. Geologic Controls of Hydrocarbon Occurrence in the Appalachian Basin in Eastern Tennessee, Southwestern Virginia, Eastern Kentucky, and Southern West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Hatcher, Robert D

    2005-11-30

    This report summarizes the accomplishments of a three-year program to investigate the geologic controls of hydrocarbon occurrence in the southern Appalachian basin in eastern Tennessee, southwestern Virginia, eastern Kentucky, and southern West Virginia. The project: (1) employed the petroleum system approach to understand the geologic controls of hydrocarbons; (2) attempted to characterize the P-T parameters driving petroleum evolution; (3) attempted to obtain more quantitative definitions of reservoir architecture and identify new traps; (4) is worked with USGS and industry partners to develop new play concepts and geophysical log standards for subsurface correlation; and (5) geochemically characterized the hydrocarbons (cooperatively with USGS). Third-year results include: All project milestones have been met and addressed. We also have disseminated this research and related information through presentations at professional meetings, convening a major workshop in August 2003, and the publication of results. Our work in geophysical log correlation in the Middle Ordovician units is bearing fruit in recognition that the criteria developed locally in Tennessee and southern Kentucky are more extendible than anticipated earlier. We have identified a major 60 mi-long structure in the western part of the Valley and Ridge thrust belt that has been successfully tested by a local independent and is now producing commercial amounts of hydrocarbons. If this structure is productive along strike, it will be one of the largest producing structures in the Appalachians. We are completing a more quantitative structural reconstruction of the Valley and Ridge and Cumberland Plateau than has been made before. This should yield major dividends in future exploration in the southern Appalachian basin. Our work in mapping, retrodeformation, and modeling of the Sevier basin is a major component of the understanding of the Ordovician petroleum system in this region. Prior to our

  2. Conditions and potential evaluation of the uranium mineralization in volcanic basins at the west section of the Yanliao mineral belt

    International Nuclear Information System (INIS)

    The West section of the Yanliao Mineral Belt is an important prospective uranium mineralization area in volcanic basins at North China. It has undergone three evolutionary periods and developed into six large volcanic collapse faulted basins with tri-layer structure. This leads to three times of pre-enrichment and multiple mineralization of uranium. Finally, the accumulation of uranium and superimposed reworked actions of uranium mineralization resulted in the formation of uranium deposits. After analyzing conditions of uranium mineralization, a model for uranium mineralization of mixed hydrothermal solution of multiple sources in penetrating volcanic collapse faulted basins and seven exploring criteria are suggested. On this basis the evaluation of prospect in this area is positive, and the main exploring strategy has been decided. Furthermore, five prospective areas of mineralization and three most favorable mineralization zones are selected. For exploring large size or super-large size uranium deposits in the area, the key is to strengthen the study and boring of deep layers. Thus, the mineralization in the deep layers or basement may be found. The prediction of deep blind deposits in known ore districts has been proved effectively

  3. Addressing diarrhea prevalence in the West African Middle Belt: social and geographic dimensions in a case study for Benin

    Directory of Open Access Journals (Sweden)

    Arouna Aminou

    2008-04-01

    Full Text Available Abstract Background In West Africa, the Northern Sahelian zone and the coastal areas are densely populated but the Middle Belt in between is in general sparsely settled. Predictions of climate change foresee more frequent drought in the north and more frequent flooding in the coastal areas, while conditions in the Middle Belt will remain moderate. Consequently, the Middle Belt might become a major area for immigration but there may be constraining factors as well, particularly with respect to water availability. As a case study, the paper looks into the capacity of the Middle Belt zone of Benin, known as the Oueme River Basin (ORB, to reduce diarrhea prevalence. In Benin it links to the Millennium Development Goals on child mortality and environmental sustainability that are currently farthest from realization. However, diarrhea prevalence is only in part due to lack of availability of drinking water from a safe source. Social factors such as hygienic practices and poor sanitation are also at play. Furthermore, we consider these factors to possess the properties of a local public good that suffers from under provision and requires collective action, as individual actions to prevent illness are bound to fail as long as others free ride. Methods Combining data from the Demographic Health Survey with various spatial data sets for Benin, we apply mixed effect logit regression to arrive at a spatially explicit assessment of geographical and social determinants of diarrhea prevalence. Starting from an analysis of these factors separately at national level, we identify relevant proxies at household level, estimate a function with geo-referenced independent variables and apply it to evaluate the costs and impacts of improving access to good water in the basin. Results First, the study confirms the well established stylized fact on the causes of diarrhea that a household with access to clean water and with good hygienic practices will, irrespective of

  4. Mianlüe tectonic zone and Mianlüe suture zone on southern margin of Qinling-Dabie orogenic belt

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The Mianlue tectonic zone (Mianlue zone), an ancient suture zone in addition to theShangdan suture in the Qinling-Dabie orogenic belt, marks an important tectonic division geo-logically separating north from south and connecting east with west in China continent. To de-termine present structural geometry and kinematics in the Mianlue tectonic zone and to recon-struct the formation and evolution history involving plate subduction and collision in theQinling-Dabie orogenic belt, through a multidisciplinary study, are significant for exploring themountain-building orogenesis of the central orogenic system and the entire process of the majorChinese continental amalgamation during the Indosinian.

  5. Proposed shallow drilling at the interface between the southern Oklahoma aulacogen and Ouachita fold belt, Arbuckle Mountains region, Oklahoma

    Energy Technology Data Exchange (ETDEWEB)

    Lidiak, E.G. (Univ. of Pittsburgh, PA (United States). Dept. of Geology and Planetary Science); Denison, R.E.

    1993-02-01

    Two major tectonic elements in southern North America are the southern Oklahoma aulacogen and the Ouachita foldbelt. The Aulacogen is characterized by basement-cored high-angle fault blocks along which movement occurred throughout much of Paleozoic time. It is one of the most intensely deformed areas in the stable interior platform of the craton. The fold belt, in contrast, consists primarily of thin-skinned compressional structures that formed in Late Paleozoic time. These two prominent tectonic features strike at a high angle to one another and are juxtaposed in southeast Oklahoma where the contact is buried shallowly beneath Cretaceous rocks of the Gulf Coastal Plain. A drilling program comprised of a series of shallow holes drilled across the contact zone will establish the structural and stratigraphic relationships at this important tectonic interface. The results obtained should be critical in elucidating the effect that the transverse aulacogen structures had on the development of the Ouachita frontal zone. Proposed drilling sites are in northern Bryan and Choctaw counties, Oklahoma, along the Tishomingo--Belton anticlines southeast of the basement-cored eastern Arbuckle Mountains. Crystalline rocks in this region are massive middle Proterozoic granitoid rocks overlain by Cretaceous sedimentary rocks. Farther southeast, rocks in the frontal zone consist mainly of Late Paleozoic flysch-type sedimentary rocks. Depths to Paleozoic and older rocks beneath the coastal plain deposits are about 300--500 meters so that targeted structures can easily be reached.

  6. Impact of immigration on HIV-1 molecular epidemiology in West Africa, Maghreb and Southern Europe.

    Science.gov (United States)

    Miri, Lamia; Wakrim, Lahcen; Kassar, Hassène; Hemminki, Kari; Khyatti, Meriem

    2014-01-01

    There is global concern about the relation between international migration and the course of the AIDS epidemic. Maghreb is a North African region, which lies between sub-Saharan Africa and Europe. It has been turned recently into a region of immigration, since there are more and more flows of West African migrants hoping to reach European countries. Here we provide an overview on HIV-1 molecular epidemiology particularly in West African countries, Maghreb (Morocco, Algeria, Tunisia) and southern European countries (Spain, France, and Italy). The studies conducted in several countries of the region revealed different features of HIV-1 molecular epidemiology, especially for the distribution of viral subtypes and for transmitted drug resistance profiles. Furthermore, migration from West Africa to Europe seems to be a potential source of non-B subtype mobility to Maghreb and eventually to southern Europe, where HIV-1 non-B variants significantly increased in the last 10 to 15 years. As genetic differences between subtypes might impact the drug resistance pathways, it is important to provide continuous surveillance programs for the early detection of new variants spreading in the population before they become more prevalent, and to identify resistance profiles in different infected populations, especially migrants. PMID:24802562

  7. Large scale prediction of soil properties in the West African yam belt based on mid-infrared soil spectroscopy

    Science.gov (United States)

    Baumann, Philipp; Lee, Juhwan; Paule Schönholzer, Laurie; Six, Johan; Frossard, Emmanuel

    2016-04-01

    Yam (Dioscorea sp.) is an important staple food in West Africa. Fertilizer applications have variable effects on yam tuber yields, and a management option solely based on application of mineral NPK fertilizers may bear the risk of increased organic matter mineralization. Therefore, innovative and sustainable nutrient management strategies need to be developed and evaluated for yam cultivation. The goal of this study was to establish a mid-infrared soil spectroscopic library and models to predict soil properties relevant to yam growth. Soils from yam fields at four different locations in Côte d'Ivoire and Burkina Faso that were representative of the West African yam belt were sampled. The project locations ranged from the humid forest zone (5.88 degrees N) to the northern Guinean savannah (11.07 degrees N). At each location, soils of 20 yam fields were sampled (0-30 cm). For the location in the humid forest zone additional 14 topsoil samples from positions that had been analyzed in the Land Degradation Surveillance Framework developed by ICRAF were included. In total, 94 soil samples were analyzed using established reference analysis protocols. Besides soils were milled and then scanned by fourier transform mid-infrared spectroscopy in the range between 400 and 4000 reciprocal cm. Using partial least squares (PLS) regression, PLS1 calibration models that included soils from the four locations were built using two thirds of the samples selected by Kennard-Stones sampling algorithm in the spectral principal component space. Models were independently validated with the remaining data set. Spectral models for total carbon, total nitrogen, total iron, total aluminum, total potassium, exchangeable calcium, and effective cation exchange capacity performed very well, which was indicated by R-squared values between 0.8 and 1.0 on both calibration and validation. For these soil properties, spectral models can be used for cost-effective, rapid, and accurate predictions

  8. Great Belt

    DEFF Research Database (Denmark)

    Sørensen, Carsten S.; Kristensen, Per S.; Erichsen, Lars

    This paper describes aspects of the soil investigations and geotechnical evaluations for the foundation design of the 6.6 km long Great Belt West Bridge. The gravity foundations rest predominantly on glacial tills and pre-quaternary limestone. Special investigations for assessment of the soil pro...... properties for ship impact and ice loading are described briefly, and first experiences from settlement monitoring of the structure during erection are presented....

  9. Southern Brasilia Belt (SE Brazil): tectonic discontinuities, K-Ar data and evolution during the Neoproterozoic Brasiliano orogeny

    International Nuclear Information System (INIS)

    This paper focuses the tectonic evolution of the southern brasilia belt, with emphasis on the Furnas segment, along the 21 deg C S parallel. The uppermost structural unit (Passos Nappe - PN) comprises a highly deformed metasedimentary succession interpreted as a fragment of the Neoproterozoic passive margin of western Sao francisco craton. An inverted metamorphic gradient ranging from greensvhits to lower granulite facies of medium to high-pressure regime characterizes the PN as relict of a subduction zone. The External Domain display a complex imbrication of basement rocks (Archean Piumhi greenstones, a turbiditic gaywacke succession and a calc-alkaline granitoid suite) with undated siliciclast low-grade metasedimentary rocks. The Sao Francisco Craton (SFC) comprises pre-1.8 Ga basement rocks covered by anchimetamorphic Neoproterozoic carbonatic shallow marine platform deposits of the Bambui group. The Brasiliano thrust stacking generated a coarse clastic influx of molassic character on the foreland zone of Sao Francisco Craton, coeval with the exhumation of the External Domain thrust sheets. New K-Ar determinations on mineral separates are presented an interpreted among previous data. The SFC basement rocks display Paleo-to Meesoproterozoic cooling ages. The allochthonous units, in contrast, display K-Ar ages within the 560-675 Ma range. Brasiliano thrust stacking is therefore interpreted to have taken place onto a cold Sao Francisco craton foreland, in a thin-skinned style, as basement rocks were not heated enough to have their-K-ar systems reset during the allochthony. (author)

  10. Available technologies for soil fertility replenishment in East, West and Southern Africa

    International Nuclear Information System (INIS)

    Full text: The central issue for improving agricultural productivity in Africa is how to build up and maintain soil fertility despite the low incomes of smallholder farmers and the increasing land and labour constraints they face. Soil nutrient depletion is a major bottleneck to increased land productivity in the region and has largely contributed to poverty and food insecurity. Soil nutrient depletion occurs when nutrient inflows are less than outflows. Nutrient balances are negative for many cropping systems in Africa indicating that farmers are mining their soils. The critical issue for improving agricultural productivity in Africa is therefore how to build and maintain soil fertility under the different farming systems. Over the years, a number of potential soil fertility management practices have been developed and by researchers. This paper reviews the available technologies for soil fertility replenishment in east, west and southern Africa under the key areas: inorganic fertilizers, animal manures, grain legumes, agroforestry options, soil, water and nutrient conservation, inorganic fertilizers, and integrated nutrient management and highlights the experiences in the application of these options in East, West and Southern Africa. (author)

  11. Late Pleistocene river migrations in response to thrust belt advance and sediment-flux steering - The Kura River (southern Caucasus)

    Science.gov (United States)

    von Suchodoletz, Hans; Gärtner, Andreas; Hoth, Silvan; Umlauft, Josefine; Sukhishvili, Lasha; Faust, Dominik

    2016-08-01

    One reaction of rivers toward allogenic triggers is the large-scale river channel migration in the form of avulsions or progressive lateral migrations (combing) that are widespread phenomena around the world during the late Quaternary. Because they potentially cause significant human and economic losses and significantly change geomorphic processes in the affected regions, a deeper knowledge about causes and rates is essential and furthermore helps to identify the dominant drivers of regional landscape evolution during different periods. One possible cause for river channel migrations is sediment-flux steering, i.e. the shift of rivers in sedimentary basins against a tectonically driven trend caused by transverse sediment discharge. During the last 30 years, sediment-flux steering has been investigated by field and experimental studies in extensional half-grabens with generally small-sized transverse catchments and/or volcaniclastic sedimentation. This study presents geomorphologic, geochronologic, and heavy mineral analyses together with complementary tectonomorphometric and earthquake data to investigate late Quaternary channel migrations of the Kura River in the southern foreland basin of the Greater Caucasus, a region where the late Quaternary landscape evolution is rather fragmentarily understood so far. Special emphasis of this study is given to the interplay between axial river flow and transverse sediment supply leading to sediment-flux steering. Large-scale migrations of the course of the Kura River during the late Quaternary reflect the interplay between tectonic processes leading to the southwestward advance of the Kura Fold-and-Thrust-Belt and climatically-triggered sediment-flux steering caused by aggradation phases of transverse rivers with comparatively large catchment areas in the Lesser Caucasus. During generally warmer periods such as the Holocene with fluvial incision and low sediment supply from the transverse rivers, the main Kura River could

  12. Rock Deformation, Component Migration and 18O/16O Variations during Mylonitization in the Southern Tan-Lu Fault Belt

    Institute of Scientific and Technical Information of China (English)

    YANG Xiaoyong; LIU Deliang; FENG Min; YU Qingni; WANG Kuiren

    2007-01-01

    This paper discusses the relationship between the volume loss, fluid flow and component variations in the ductile shear zone of the southern Tan-Lu fault belt. The results show that there is a large amount of fluids flowing through the shear zone during mylonitization, accompanied with the loss of volume of rocks and variations of elements and oxygen isotopes. The calculated temperature for mylonitization in different mylonites ranges from 446 to 484℃, corresponding to that of 475 to 500℃for the wall rocks. The condition of differential stress during mylonization has been obtained between 99 and 210 MPa, whereas the differential stress in the wall rock gneiss is 70-78 MPa. The mylonites are enriched by factors of 1.32-1.87 in elements such as TiO2, P2O5, MnO, Y, Zr and V and depleted in SiO2, Na2O, K2O, Al2O3, Sr, Rb and light REEs compared to their protolith gneiss. The immobile element enrichments are attributed to enrichments in residual phases such as ilmentite, zircon, apatite and epidote in mylonites and are interpreted as due to volume losses from 15% to 60% in the ductile shear zone. The largest amount of SiO2 loss is 35.76 g/100 g in the ductile shear zone, which shows the fluid infiltration. Modeling calculated results of the fluid/rock ratio for the ductile shear zone range from 196 to 1192 by assuming different degrees of fluid saturation. Oxygen isotope changes of quartz and feldspar and the calculated fluid are corresponding to the variations of differential flow stress in the ductile shear zone. With increasing differential flow stress, the mylonites show a slight decrease of δ18O in quartz, K-feldspar and fluid.

  13. Multi-phase Uplift of the Indo-Burman Ranges and Western Thrust Belt of Minbu Sub-basin (West Myanmar): Constraints from Apatite Fission Track Data

    Science.gov (United States)

    Zhang, P.; Qiu, H.; Mei, L.

    2015-12-01

    The forearc regions in active continental margins are important keys to analysis geodynamic processes such as oceanic crust oblique subduction, mechanism of subduction zone, and sediments recycling. The West Myanmar, interpreted as forearc silver, is the archetype example of such forearc regions subordinate to Sunda arc-trench system, and is widely debated when and how its forearc regions formed. A total of twenty-two samples were obtained from the Indo-Burman Ranges and western thrust belt of Minbu Sub-basin along Taungup-Prome Road in Southwestern Myanmar (Figure 1), and five sandstone samples of them were performed at Apatite to Zircon, Inc. Three samples (M3, M5, and M11) collected from Eocene flysch and metamorphic core at the Indo-Burman Ranges revealed apatite fission track (AFT) ages ranging from 19 to 9 Ma and 6.5 to 2 Ma. Two samples (M20 and M21) acquired from the western thrust belt of Minbu Sub-basin yielded AFT ages ranging from 28 to 13.5 Ma and 7.5 to 3.5 Ma. Time-temperature models based on AFT data suggest four major Cenozoic cooling episodes, Late Oligocene, Early to Middle Miocene, Late Miocene, and Pliocene to Pleistocene. The first to third episode, models suggest the metamorphic core of the Indo-Burman Ranges has experienced multi-phase rapidly uplifted during the early construction of the forearc regions. The latest episode, on which this study focused, indicated a fast westward growth of the Palaeogene accretionary wedge and a eastward propagation deformation of folding and thrusting of the western thrust belt of Minbu Sub-basin. We argued that above multi-phase uplifted and deformation of the forearc regions were results of India/West Burma plate's faster oblique convergence and faster sedimentation along the India/Eurasia suture zone.

  14. The Cambrian initiation of intra-oceanic subduction in the southern Paleo-Asian Ocean: Further evidence from the Barleik subduction-related metamorphic complex in the West Junggar region, NW China

    Science.gov (United States)

    Liu, Bo; Han, Bao-Fu; Xu, Zhao; Ren, Rong; Zhang, Jin-Rui; Zhou, Jing; Su, Li; Li, Qiu-Li

    2016-06-01

    In this study, we present new evidence from the Barleik subduction-related metamorphic complex in the southern West Junggar region, northwestern China, for the Cambrian initiation of intra-oceanic subduction in the southern Paleo-Asian Ocean. The Barleik metamorphic complex is mainly composed of blueschist and amphibolite blocks within an ophiolitic mélange and their protoliths are calc-alkaline andesite and alkali and tholeiitic basalts. The calc-alkaline andesite has a zircon U-Pb age of 502 ± 2 Ma, obtained from magmatic cores of zircon grains, and shares geochemical features similar to the 515-485 Ma intra-oceanic arc magmatic rocks in the West Junggar region. By contrast, the alkali and tholeiitic basalts have trace element features similar to ocean island and enriched mid-ocean ridge basalts, respectively. Rutile and sodic-calcic amphibole from the amphibolite have a U-Pb age of 502 ± 25 Ma and a 40Ar/39Ar age of ∼504 Ma, respectively, which are in good agreement within errors with a 40Ar/39Ar age of 492 ± 4 Ma for phengite from the blueschist. These metamorphic ages of ∼500 Ma are interpreted to represent the timing of Pacific-type subduction-related metamorphism and are also compatible with ages of the oldest supra-subduction zone ophiolites (531-512 Ma) and intra-oceanic arc plutons (515-485 Ma) in the southern West Junggar region. Being one of the oldest subduction-related metamorphic complexes (509-490 Ma) in the southern Central Asian Orogenic Belt, the Barleik metamorphic complex, together with the oldest arc plutons, definitely indicate the initial intra-oceanic subduction in the southern Paleo-Asian Ocean at least in the Early Cambrian.

  15. Further evidence of 777 Ma subduction-related continental arc magmatism in Eastern Dom Feliciano Belt, southern Brazil: The Chácara das Pedras Orthogneiss

    Science.gov (United States)

    Koester, E.; Porcher, C. C.; Pimentel, M. M.; Fernandes, L. A. D.; Vignol-Lelarge, M. L.; Oliveira, L. D.; Ramos, R. C.

    2016-07-01

    In this study new SHRIMP U-Pb zircon data for the Chácara das Pedras Gneiss in Porto Alegre, southern Brazil are presented. They represent a small exposure of the crust which was intruded by a large volume of orogenic to anorogenic granitoids at ca. 618-562 m.y. in the Eastern Domain of the Dom Feliciano Belt. The Chácara das Pedras tonalitic orthogneiss has geochemical similarities with subduction-related magmatic rocks of continental arcs. They present high Sr initial ratios (∼0.712), negative ɛNd(t = 777) values (∼-6), TDM varying from 1.8 to 2.0 Ga. The igneous protoliths of these orthogneisses were previously considered to be Paleoproterozoic based on an upper intercept age of discordant zircon analyses. In the present study these orthogneisses were re-sampled and re-analyzed in an attempt to obtain more concordant analytical data. The U-Pb zircon analyses were carried out using the SHRIMP IIe at the Laboratório de Geocronologia de Alta Resolução of the Universidade de São Paulo. The U-Pb concordia age obtained for igneous textural domains of the zircon grains is 777 ± 4 Ma. A few analyses on zircon overgrowths give poorly defined late Cryogenian ages of ca. 650 Ma. Older ages, mostly discordant, were obtained in a few zircon cores, showing an upper intercept age of ca. 1.9 Ga. One sample of the Três Figueiras Granodiorite, which crosscut the orthogneiss in the same outcrop, was also investigated. The zircons of this granodiorite are, however, mostly metamitic, preventing the determination of a reliable age. Some concordant analyses from a few grains define ages ranging in the interval between ca. 603 and 1022 Ma. The youngest (ca. 603 Ma) may represent a maximum age for the granodiorite crystallization. Older ages, with discordance magmatic age determined for granitoids in the Porto Alegre region, although records of similar ages (780-800 Ma) are recognized within the Eastern Domain of the Dom Feliciano Belt. Examples are the Piratini Gneisses

  16. Gender Statistics in the Southern Caucasus and Central and West Asia: A Situational Analysis Promoting Gender-Inclusive Growth in Central and West Asian Developing Member Countries

    OpenAIRE

    Asian Development Bank (ADB)

    2012-01-01

    This report provides a baseline of the capacity of Asian Development Bank developing member countries to generate, analyze, disseminate, and use sex-disaggregated data. It introduces a framework on gender statistics and guides in assessing statistical systems in the Southern Caucasus (Armenia, Azerbaijan, Georgia), Central Asia (Kazakhstan, Kyrgyz Republic, Tajikistan, Turkmenistan, Uzbekistan), and West Asia (Afghanistan, Pakistan). It recommends ways to bridge the gaps in gender data collec...

  17. Mesozoic tectonic evolution of the Daba Shan Thrust Belt in the southern Qinling orogen, central China: Constraints from surface geology and reflection seismology

    Science.gov (United States)

    Li, Jianhua; Dong, Shuwen; Yin, An; Zhang, Yueqiao; Shi, Wei

    2015-08-01

    The Daba Shan Thrust Belt is located along the southern margin of the Qinling orogen that separates the north China block in the north from the south China block in the south. Despite decades of research, the total magnitude of shortening accommodated by continent-continent convergence across the Qinling orogen after Triassic ocean closure between north and south China remains poorly constrained. The lack of knowledge on the shortening magnitude in turn limits our ability to test a wide array of tectonic models for the development of the Qinling orogen and thus the convergence history between north and south China. In order to address this issue, we construct a balanced cross section and develop a new kinematic model for the evolution of the Daba Shan Thrust Belt. This work was accomplished by integrating (1) surface geologic mapping, (2) detailed kinematic analysis of key structures, (3) existing geochronologic and thermochronological data, and (4) a recently obtained lithospheric-scale seismic reflection profile. Restoration of the cross section indicates that the minimum shortening strain increases northward from ~10% in the foreland to >45% in the thrust belt interior. The estimated amount of upper crustal shortening across the Daba Shan Thrust Belt is >130 km, which is sufficient to allow the inferred mafic lower crust of the subducted south China lithosphere to have experienced eclogite phase transition. Thus, our work supports that the development of the Daba Shan Thrust Belt may have been driven by slab pull of the subducted mafic lower crust at the leading edge of the down-plunging south China continental lithosphere.

  18. Structure and SHRIMP U/Pb zircon ages of granites adjacent to the Chitradurga Schist belt: implications for neoarchaean convergence in the Dharwar Craton, Southern India

    International Nuclear Information System (INIS)

    Neoarchaean granites adjacent to the Chitradurga schist belt were emplaced in thc inner margin of the foreland in the context of the Neoarchaean oblique convergent setting of the Dharwar craton. Two previously unreported granites, one 50 km and the other 80 km NW of Chitradurga town, and a mylonitised granite in the hanging wall of a duplex in the NW of the schist belt yielded SHRIMP U/Pb zircon emplacement ages of 2648±40 Ma, 2598± 19 Ma, and ca. 2600 Ma, respectively, the large errors being due to radiogenic Pb loss during an unidentified Neoproterozoic event. Some discrete zircon grains and xenocrystic cores yielded ≥3000 Ma ages that were derived from older rocks during anatexis or emplacement. The granites NW of Chitradurga town were emplaced as steep sheets trending NW-SE. The Chitradurga granite has a similar form, bifurcating N of Chitradurga town into two separate, steeply dipping, NW-SE sheets. Magmatic- and solid-state fabrics in these granites show that emplacement took place during, but was outlasted by, sinistral and dextral strike-parallel shear. Emplacement of the granite above the hanging wall of the duplex in the NW of the schist belt was outlasted by top-SW displacement. The shapes of the granites and their emplacement in relation to the structure of the Ranibennur and Chitradurga schist belts in the west of the craton are modelled as a mid-crustal part of a craton-wide imbricate fold-thrust belt. The relationships show that whereas some Neoarchaean granites in the craton were emplaced prior to, or during, SW -vergent thrust thickening, most granites and related plutonic suites in the foreland and accretionary complex were emplaced later as multipulse injections in steep NW-SE sheets or wedges during orogen-parallel, sinistral and dextral shear. Steep high- strain zones in the foreland and accretionary complex are interpreted as listric structures that root into an attachment at a depth of ca. 18-20 km in accord with the depth of the boundary

  19. Emplacement kinematics of nepheline syenites from the Terrane Boundary Shear Zone of the Eastern Ghats Mobile Belt, west of Khariar, NW Orissa: Evidence from meso- and microstructures

    Indian Academy of Sciences (India)

    T K Biswal; Harish Ahuja; Himansu Sekhar Sahu

    2004-12-01

    Nepheline syenite plutons emplaced within the Terrane Boundary Shear Zone of the Eastern Ghats Mobile Belt west of Khariar in northwestern Orissa are marked by a well-developed magmatic fabric including magmatic foliation, mineral lineations, folds and S-C fabrics. The minerals in the plutons, namely microcline, orthoclase, albite, nepheline, hornblende, biotite and aegirine show, by and large, well-developed crystal faces and lack undulose extinction and dynamic recrystallization, suggesting a magmatic origin. The magmatic fabric of the plutons is concordant with a solid-state strain fabric of the surrounding mylonites that developed due to noncoaxial strain along the Terrane Boundary Shear Zone during thrusting of the Eastern Ghats Mobile Belt over the Bastar Craton. However, a small fraction of the minerals, more commonly from the periphery of the plutons, is overprinted by a solid state strain fabric similar to that of the host rock. This fabric is manifested by discrete shear fractures, along which the feldspars are deformed into ribbons, have undergone dynamic recrystallization and show undulose extinction and myrmekitic growth. The shear fractures and the magmatic foliations are mutually parallel to the C-fabric of the host mylonites. Coexistence of concordant solid state strain fabric and magmatic fabric has been interpreted as a transitional feature from magmatic state to subsolidus deformation of the plutons, while the nepheline syenite magma was solidifying from a crystal-melt mush state under a noncoaxial strain. This suggests the emplacement of the plutons synkinematic to thrusting along the Terrane Boundary Shear Zone. The isotopic data by earlier workers suggest emplacement of nepheline syenite at 1500 + 3/− 4Ma, lending support for thrusting of the mobile belt over the craton around that time.

  20. Importance of Wetlands Management for West Nile Virus Circulation Risk, Camargue, Southern France

    Directory of Open Access Journals (Sweden)

    Sophie Pradier

    2014-08-01

    Full Text Available To assess environmental and horse-level risk factors associated with West Nile Virus (WNV circulation in Camargue, Southern France, a serosurvey was conducted on non-vaccinated horses (n = 1159 from 134 stables in 2007 and 2008. Fifteen Landsat images were examined to quantify areas with open water and flooded vegetation around sampled horses. Mean percentages of areas of open water and flooded vegetation, as well as variations in these percentages between 3 periods (November to February = NOT, March to July = END and August to October = EPI, were calculated for buffers of 2 km radius around the stables. Results of the final logistic regression showed that the risk of WNV seropositivity in horses decreased with their date of acquisition and age. Results also demonstrated the significant role of environmental variables. Horse serological status was associated with variations of open water areas between the NOT (November to February and END (March to July periods, as well as between END and EPI (August to October. WNV spillover was found more intense in areas where water level decreased strongly from winter to spring and from spring to summer.

  1. Seismotectonic Study on the West Part of the Interaction Zone Between Southern Tianshan and Northern Tarim

    Institute of Scientific and Technical Information of China (English)

    Tian Qinjian; Ding Guoyu; Hao Ping

    2007-01-01

    The interaction zone between southern Tianshan and northern Tarim is located at the northeast side of Pamir.It is a region with high seismicity.We constructed a seismotectonic model for the west part of this zone from geological profiles,deep crust seismic detection and earthquake focal mechanisms data.Based on the synthesized geological features,deep crust structure,and earthquake focal mechanisins,we think that the main regional tectonic feature is that the Tianshan recto-lithostratigraphic unit overthrusts on the Tarim block.The Tianshan tectonic system includes the Maidan fault and thrust sheets in front of the fault;The Tarim tectonic system includes the underground northern Tarim margin fault,conjugate faults in basement and overthrust fault in shallow.The northern Tarim margin fault is a high angle fault deep in the Tarim crust, adjusting difierent trending deformation between Tianshan and Tarim.It is a major active fault that can generate large earthquakes.The other faults,such as the Tianshan overthrnst system and the Tarim basement faults in this area may generate moderately strong earthquakes with different styles.

  2. Crustal structure in the southern part of West Java based on analysis of teleseismic receiver function

    Science.gov (United States)

    Syuhada, Anggono, Titi

    2016-02-01

    We analyzed teleseismic receiver functions from five broadband stations to determine the crustal thickness and Vp/vs ratios in the southern part of west Java. We observed that the study area is characterized by crustal thickness around 31-37 km with Vp/Vs varying between 1.66 and 1.87. We suggest that lower values of Vp/Vs obtained in some stations indicate more felsic crustal composition. The mid-crust low velocity zone is observed beneath a seismic station located near the volcanic zones with high values of Vp/Vs ratio suggesting the presence of partial melt due to geothermal activities in the upper mantle. Furthermore, a seismic station located near the active fault zone also has high Vp/Vs ratio, which may indicate the presence of fluid filled fracture zone. However, this station exhibits complicated receiver functions, thus it needs further research involving a larger dataset with good backazimuth coverage of the teleseismic data to resolve this issue.

  3. Impact of valley fills on streamside salamanders in southern West Virginia

    Science.gov (United States)

    Wood, Petra Bohall; Williams, Jennifer M.

    2013-01-01

    Valley fills associated with mountaintop-removal mining bury stream headwaters and affect water quality and ecological function of reaches below fills. We quantified relative abundance of streamside salamanders in southern West Virginia during 2002 in three streams below valley fills (VFS) and in three reference streams (RS). We surveyed 36 10- × 2-m stream transects, once in summer and fall, paired by order and structure. Of 2,343 salamanders captured, 66.7% were from RS. Total salamanders (adults plus larvae) were more abundant in RS than VFS for first-order and second-order reaches. Adult salamanders had greater abundance in first-order reaches of RS than VFS. Larval salamanders were more abundant in second-order reaches of RS than VFS. No stream width or mesohabitat variables differed between VFS and RS. Only two cover variables differed. Silt cover, greater in VFS than RS first-order reaches, is a likely contributor to reduced abundance of salamanders in VFS. Second-order RS had more boulder cover than second-order VFS, which may have contributed to the higher total and larval salamander abundance in RS. Water chemistry assessments of our VFS and RS reported elevated levels of metal and ion concentrations in VFS, which can depress macroinvertebrate populations and likely affect salamander abundance. Valley fills appear to have significant negative effects on stream salamander abundance due to alterations in habitat structure, water quality and chemistry, and macroinvertebrate communities in streams below fills.

  4. Neoglacial and historical glacier changes around Kangersuneq fjord in southern West Greenland

    Directory of Open Access Journals (Sweden)

    Weidick, Anker

    2012-12-01

    Full Text Available The Nuup Kangerlua region in southern West Greenland became eglaciated in the early Holocene and by the mid-Holocene, the margin of the Inland Ice was located east of its present position. Discussion of late Holocene changes in the frontal positions of outlets relies on descriptions, paintings, photographs, maps, data from investigations of Norse ruins, aerial photographs and satellite images.The Kangiata Nunaata Sermia glacier system has receded over 20 km during the last two centuries, indicating a marked response to climatic fluctuations during and since the Little Ice Age (LIA. A large advance between 1700 and 1800 was followed by rapid recession in the first half of the 1800s. Limited data from c. 1850–1920 indicate that although the long-term position of the glacier front remained c. 10–12 km behind the LIA maximum, the late 1800s and the early 1900s may have seen a recession followed by an advance that resulted in a pronounced moraine system. The ice-dammed lake Isvand formed during the LIA maximum when meltwater from the western side of Kangiata Nunaata Sermia drained to the Ameralla fjord in the west. This is in contrast to the drainage pattern before the 1700s, when water probably drained to Kangersuneq in the north. Thinning of Kangiata Nunaata Sermia resulted in total drainage of Isvand between 2000 and 2010 and the discharge of water through Austmannadalen has now returned to the same level as that in medieval times.Other outlets in the region, such as Akullersuup Sermia and Qamanaarsuup Sermia have varied in phase with Kangiata Nunaata Sermia, but with amplitudes of only a few kilometres. In contrast, Narsap Sermia has been nearly stationary and Kangilinnguata Sermia may have advanced until the middle of the 1900s.Lowland marine outlets in south-western Greenland were characterised by large amplitude changes during the Neoglacial. Extreme examples, in addition to Kangiata Nunaata Sermia, are Eqalorutsit Killiit Sermiat at the

  5. Chronic Diseases in North-West Tanzania and Southern Uganda. Public Perceptions of Terminologies, Aetiologies, Symptoms and Preferred Management

    OpenAIRE

    Soori Nnko; Dominic Bukenya; Bazil Balthazar Kavishe; Samuel Biraro; Robert Peck; Saidi Kapiga; Heiner Grosskurth; Janet Seeley

    2015-01-01

    Background Research has shown that health system utilization is low for chronic diseases (CDs) other than HIV. We describe the knowledge and perceptions of CDs identified from rural and urban communities in north-west Tanzania and southern Uganda. Methods Data were collected through a quantitative population survey, a quantitative health facility survey and focus group discussions (FGDs) and in-depth interviews (IDIs) in subgroups of population survey participants. The main focus of this pape...

  6. Hydrologic reconnaissance of the southern Great Salt Lake Desert and summary of the hydrology of west-central Utah

    Science.gov (United States)

    Gates, Joseph S.; Kruer, Stacie A.

    1981-01-01

    This report is the last of 19 hydrologic reconnaissances of the basins in western Utah. The purposes of this series of studies are (1) to analyze available hydrologic data and describe the hydrologic system, (2) to evaluate existing and potential water-resources development, and (3) to identify additional studies that might be needed. Part 1 of this report gives an estimate of recharge and discharge, an estimate of the potential for water-resources development, and a statement on the quality of water in the southern Great Salt Lake Desert part of west-central Utah. Part 2 deals with the same aspects of west-central Utah as a whole. Part 2 also summarizes the evidence of interbasin ground-water flow in west-central Utah and presents a theory for the origin of the water discharged from Fish Springs.

  7. Results of a paleomagnetic survey undertaken in the Damara mobile belt, South West Africa, with special reference to the magnetisation of the uraniferous pegmatitic granites

    International Nuclear Information System (INIS)

    A project study, undertaken by the Geology Division of the AEB, on the correlation between airborne magnetic and radiometric data covering a portion of the Damara Mobile Belt in South West Africa, has revealed that all the known occurrences of uranium in late- to post-tectonic leucogranite (alaskite) of the Damara orogeny are associated with negative geomagnetic anomalies. Although the uranium occurrences themselves do not display marked geomagnetic anomalies, their immediate geological environment is characterised by the negative anomalies, which are semi-regional in extent. To investigate the origin of these anomalies, the Atomic Energy Board and the Geological Survey of South Africa undertook a palaeomagnetic study of the area. Oriented cores were taken from 31 sites in the mobile belt, 18 of which were selected within the negative magnetic zones, mostly in close association with known uraniferous alaskitic granites. Palaeomagnetic evidence suggests that the negative geomagnetic anomalies are associated with a remanent magnetisation, resulting from the Damara orogenic event, whose direction is removed from the earth's present field and which has affected rocks of the Nosib Group. Absence of this stable remanent direction in rocks stratigraphically overlying the Nosib Group accounts for the distinctive geomagnetic signature, in the form of negative anomalies, of the Nosib Group. It is this signature which can be used in airborne surveys to identify rocks of the Nosib Group outcropping, or of shallow suboutcrop, in anticlinal or dome-like structures. Since the uraniferous alaskites are mostly confined stratigraphically to the Nosib Group, the negative geomagnetic anomalies form an important prospecting criterion as they may be used to delineate target areas for further exploration in areas covered by sand, scree and duricrust deposits

  8. Research of the structural evolution and its action on uranium mineralization of Nanxiong fracture belt, southern China

    International Nuclear Information System (INIS)

    By studying the sediment formations in the basin to the southeast of Naxiong fracture belt and the lithologic composition of structre rocks, this paper discusses the the origination and development, evolution of structural dynamics, fracture pattern and locating pattern of uranium deposits. It was suggested that the NW striking tensional fractures matched to Nanxiong fracture belt during the intensely compress periond were the intrusive passageway of mantle magmatism and deep hydrothermal fluid, and the store place for uranium deposit. The furthering efforts should focus on the covert NW extending fractures by selecting available geophysical and geochemical detecting method to identify the these fractures in exactly position of outcrop,change of occurrence and spacial pattern and validated them with drilling so as to deepen the recognition of uranium mineralization pattern and expand the prospecting achievement. (authors)

  9. Participatory planning in river catchments, an innovative toolkit tested in Southern Africa and North West England.

    Science.gov (United States)

    Tippett, J

    2005-01-01

    The European Union Water Framework Directive (WFD) offers an unparalleled opportunity for improving river basin management. Active participation is essential for its delivery. "End-of-pipe" solutions will not deliver the improvements needed to achieve its ambitious goals. This research tested DesignWays, a toolkit for participatory planning, as a mechanism for maximizing the long-term social and environmental benefits of such stakeholder and community participation. It examined the emerging role of "planning for sustainability" in the context of river catchments. Sustainable management of water requires integration, and recognition of interconnections between systems at different levels of scale. This is an endeavour in which systems thinking provides useful tools. The development of DesignWays was a conscious attempt to embed 'new paradigm' living systems metaphors into a practical planning tool. This paper begins with a description of DesignWays and its development in Southern Africa. An outline of the context of the action research in North-West England is followed by a description of the stages of the process, with highlights of the outcomes. This research had two major outcomes: a contribution to theory through an in-depth exploration of the theoretical basis of participatory, ecologically informed design; and a contribution to practice through investigating DesignWays' potential to meet key challenges of the WFD. This research points to the importance of understanding participatory planning as a societal process, aiming to make the process engaging and meaningful. It has pointed to the need to see participatory planning and education for sustainability as an integrated process. It demonstrated the benefits of an iterative process in which planning at the landscape level of scale informs, and is informed by, work at the site level. It has shown that an approach consistent with a living systems paradigm can contribute to the development of more integrated

  10. Timing of Deformation in the Central Metasedimentary Belt Boundary Thrust Zone (CMBbtz), southern Ontario, Canada, from Electron Microprobe Dating of Monazite

    Science.gov (United States)

    Markley, M. J.; Dunn, S. R.; Peck, W. H.; Jercinovic, M. J.; Williams, M. L.

    2015-12-01

    In the Grenville Province of Southern Ontario, the Central Metasedimentary Belt boundary thrust zone (CMBbtz) is a crustal-scale tectonic boundary between the older, granulite-facies Central Gneiss Belt to the NW and the younger, amphibolite-facies Central Metasedimentary Belt to the SE. Although there are a range of tectonic models for the CMBbtz, most workers agree it is a major tectonic boundary that accommodated ductile thrusting and crustal shortening during the Ottawan phase of the Grenville Orogeny (~1080-1020 Ma). Some studies suggest that ductile thrusting in the CMBbtz was roughly synchronous with synorogenic extensional collapse below an orogenic lid. Previous geochronological studies also provide evidence of earlier deformation and/or metamorphic events in the CMBbtz, although the relation between deformation in the CMBbtz to the Elzeviran (~1230 Ma) and Shawinigan (~1180 Ma) orogenies is unclear. Our study is the first to report in situ electron microprobe monazite (mnz) dates from amphibolite-grade ortho- and para-gneisses of the CMBbtz. Our results are broadly consistent with other chronometers. We present dates from 132 age-domains within 83 mnz grains in 14 samples. Although our data provide strong evidence for deformation and metamorphism along the length of the CMBbtz during the Ottawan (1080-1020 Ma), we also report two other clusters of ages: 1140-1110 Ma and 1230-1170 Ma. The latter cluster falls between the widely accepted ranges for the Elzeviran and Shawinigan orogenies. In addition, some individual outcrops, particularly those in Killaloe and Minden, show mnz ages spanning over 200 m.y., and the setting and compositions of individual monazite domains allow us to link mnz growth to episodes of garnet growth during multiple events. Together these data indicate an unexpectedly continuous and long-lived period of deformation and metamorphism in the CMBbtz.

  11. Tectono-metamorphic evolution and timing of the melting processes in the Svecofennian Tonalite-Trondhjemite Migmatite Belt: An example from Luopioinen, Tampere area, southern Finland

    Directory of Open Access Journals (Sweden)

    Mouri, H.

    1999-06-01

    Full Text Available The Svecofennian Orogen is in southern Finland characterized by two major migmatite belts. These are the so-called Granite Migmatite Belt, in which Kfs-rich leucosomes predominate, and the Tonalite-Trondhjemite Migmatite Belt, which is characterized by Kfs-poor leucosomes and borders the former belt in the north. The present paper deals with selected migmatitic rocks from the latter belt. It is aimed to study the temporal and structural relationships of the different leucosome generations, and to establish the pressure-temperature-time paths of this belt. The Tonalite-Trondhjemite Migmatite Belt consists mainly of migmatitic rocks with various types of synorogenic granitoids and minor mafic and ultramafic crocks. The mesosome of the migmatites consist of garnet-sillimanite-biotite-plagioclase-cordierite-quartz assemblages with rare K-feldspar and late andalusite. The oldest leucosomes are dominated by plagioclase and quartz, and the content of K-feldspar increases in later leucosomes. Microtextural analysis in conjunction with THERMOCALC calculations and geothermometry shows that these rocks were metamorphosed at peak conditions of 700-750°C at 4-5 kbar and aH20 = 0.4-0.7. The formation of cordierite coronas around garnet and the late crystallization of andalusite suggest that the final stage of the P-T history was characterized by decompression and cooling within the andalusite stability field, estimated at 500-650°C and 3-4 kbar. Detailed isotopic dating of mesosome and leucosomes of the migmatites was undertaken by conventional U-Pb analyses on monazite and zircon, Sm-Nd analyses on garnet, and ion probe dating on zircon. The monazites are nearly concordant with an average age of 1878.5±1.5 Ma, and garnet-whole rock analyses show that the concordant leucosomes and the mesosome are coeval within error margins having ages of 1893±40 and 1871±14 Ma, respectively. However, garnet in the discordant vein leucosome provides an age of 1843±11

  12. Provenance of the Passo Feio complex, Dom Feliciano Belt: Implications for the age of supracrustal rocks of the São Gabriel Arc, southern Brazil

    Science.gov (United States)

    Lopes, Carina Graciniana; Pimentel, Marcio Martins; Philipp, Ruy Paulo; Gruber, Leonardo; Armstrong, Richard; Junges, Sergio

    2015-03-01

    The Passo Feio complex (PFC) is a sequence of metapelite, amphibolite, metavolcanic/metavolcanoclastic rocks, marble, calc-silicate rocks, quartzite and magnesium schist. It is part of the São Gabriel Terrane, a Neoproterozoic juvenile arc formed during the early stages of evolution of the Neoproterozoic Dom Feliciano Belt (DFB), in southern Brazil. This belt corresponds to the southernmost portion of the Mantiqueira Province, an important Neoproterozoic orogenic system exposed in the NNE direction along the southeastern coast of Brazil. The geotectonic significance of the original Passo Feio basin in the tectonic evolution of São Gabriel Terrene is not well understood. It has been considered as part of a passive margin sequence or as a back-arc sequence. Geochronological and isotopic data are very scarse for the Passo Feio rocks and this has hampered the better understanding of its significance in the Neoproterozoic tectonic evolution of southern Brazil. In the present study the age and significance of metasedimentary rocks of the PFC were investigated. The provenance study was carried out in four metapelite samples from the southern and northern Passo Feio complex, using U-Pb dating of detrital zircon. The results showed varied provenance patterns and zircon ages range from 3637 to 803 Ma. Paleo- and Mesoproterozoic detrital zircon grains are present in all samples, but an important Neoproterozoic population has been identified in one of them. 3.5 Ga old zircon grains form the oldest population of detrital zircon ever reported in southern Brazil. Paleoproterozoic/Archean terranes within the Rio de la Plata Craton may represent the main source of detrital sediments and this suggests that part of the Passo Feio complex might have been a passive margin sequence, developed along the northeastern margin of that paleocontinent. However, the presence of a Neoproterozoic zircon population is not consistent with derivation solely from the craton and indicates

  13. Comparison of radio data and model calculations of Jupiter's synchrotron radition 2. East--west asymmetry in the radiation belts as a functon of Jovian longitude

    International Nuclear Information System (INIS)

    On the basis of comparison of radio data and model calculations of Jupiter's synchrotron radiaton the 'hot region' or east--west asymmetry in the planet's radiation belts is proposed to be due to the combined effect of an overabundance of electrons at jovicentric longitudes lambda/sub J/approx.240 0--360 0 and the existence of a dusk dawn directed electric field over the inner magnetosphere, generated by the wind system in the upper atmosphere. The model calculations were based upon the magnetic field configurations derived from the Pioneer data by Acuna and Ness [1976] (the O4 model) and Davis, Jones and Smith (quoted in Smith and Gulkis [1979]) (the P11 (3,2)A model), with an electron distribution derived in the first paper of this series [de Pater, this issue]. We would infer from the calculations that the O4 model gives a slightly better fit to the data; the relatively large number density at lambda/sub J/approx.240 0--360 0, however, might indicate the presence of even higher order moments in the field

  14. Detrital zircon age distribution from Devonian and Carboniferous sandstone in the Southern Variscan Fold-and-Thrust belt (Montagne Noire, French Massif Central), and their bearings on the Variscan belt evolution

    Science.gov (United States)

    Lin, Wei; Faure, Michel; Li, Xian-hua; Chu, Yang; Ji, Wenbin; Xue, Zhenhua

    2016-05-01

    In the Southern French Massif Central, the Late Paleozoic sedimentary sequences of the Montagne Noire area provide clues to decipher the successive tectonic events that occurred during the evolution of the Variscan belt. Previous sedimentological studies already demonstrated that the siliciclastic deposits were supplied from the northern part of the Massif Central. In this study, detrital zircon provenance analysis has been investigated in Early Devonian (Lochkovian) conglomerate and sandstone, and in Carboniferous (Visean to Early Serpukhovian) sandstone from the recumbent folds and the foreland basin of the Variscan Southern Massif Central in Montagne Noire. The zircon grains from all of the samples yielded U-Pb age spectra ranging from Neoarchean to Late Paleozoic with several age population peaks at 2700 Ma, 2000 Ma, 980 Ma, 750 Ma, 620 Ma, 590 Ma, 560 Ma, 480 Ma, 450 Ma, and 350 Ma. The dominant age populations concentrate on the Neoproterozoic and Paleozoic. The dominant concordant detrital zircon age populations in the Lochkovian samples, the 480-445 Ma with a statistical peak around 450 Ma, are interpreted as reflecting the rifting event that separated several continental stripes, such as Armorica, Mid-German Crystalline Rise, and Avalonia from the northern part of Gondwana. However, Ediacaran and Cambrian secondary peaks are also observed. The detrital zircons with ages at 352 - 340 Ma, with a statistical peak around 350 Ma, came from the Early Carboniferous volcanic and plutonic rocks similar to those exposed in the NE part of the French Massif Central. Moreover, some Precambrian grains recorded a more complex itinerary and may have experienced a multi-recycling history: the Archean and Proterozoic grains have been firstly deposited in Cambrian or Ordovician terrigenous rocks, and secondly re-sedimented in Devonian and/or Carboniferous formations. Another possibility is that ancient grains would be inherited grains, scavenged from an underlying but not

  15. Climatology and dynamics of nocturnal low-level stratus over the southern West African monsoon region

    Science.gov (United States)

    Fink, A. H.; Schuster, R.; Knippertz, P.; van der Linden, R.

    2013-12-01

    The southern parts of West Africa, from the coast to about 10°N, are frequently covered by an extensive deck of shallow, low (200 - 400 m above ground) stratus or stratocumulus clouds during the summer monsoon season. These clouds usually form at night in association with a nocturnal low-level jet (NLLJ) and can persist into the early afternoon hours until they are dissipated or replaced by fair-weather cumuli. Recent work suggests that the stratus deck and its effect on the surface radiation balance are unsatisfactorily represented in standard satellite retrievals and simulations by state-of-the-art climate models. We will present the first ever climatology of the diurnal cycle of the low cloud deck based on surface observations and satellite products. In addition, we use high-resolution regional simulations with the Weather Research and Forecast (WRF) model and observations from the African Monsoon Multidisciplinary Analysis (AMMA) 2006 campaign to investigate (a) the spatiotemporal distribution, (b) the influence on the radiation balance, and (c) the detailed formation and maintenance mechanisms of the stratiform clouds as simulated by the model. The model configuration used for this study has been determined following an extensive sensitivity study, which has shown that at least some configurations of WRF satisfactorily reproduce the diurnal cycle of the low cloud evolution. The main conclusions are: (a) The observed stratus deck forms after sunset along the coast, spreads inland in the course of the night, reaches maximum poleward extent at about 10°N around 09-10 local time and dissipates in the early afternoon. (b) The average surface net radiation balance in stratus-dominated regions is 35 W m-2 lower than in those with less clouds. (c) The cloud formation is related to a subtle balance between 'stratogenic' upward (downward) fluxes of latent (sensible) heat caused by shear-driven turbulence below the NLLJ, cold advection from the ocean, forced lifting at

  16. An overview of the lithological and geochemical characteristics of the Mesoarchean (ca. 3075) Ivisaartoq greenstone belt, southern West Greenland

    DEFF Research Database (Denmark)

    Polat, A.; Frei, Robert; Appel, P.W.U.;

    2008-01-01

    Ca-plagioclase and are interpreted as anorthositic cumulates of the lower oceanic crust brought to the surface by upwelling gabbroic magmas. Alternatively, the inclusions may represent the xenoliths from older (>3075 Ma) anorthositic crust onto which the Ivisaartoq magmas were emplaced as an...

  17. Eclogite-high-pressure granulite metamorphism records early collision in West Gondwana: new data from the Southern Brasilia Belt, Brazil

    DEFF Research Database (Denmark)

    Reno II, Barry Len; Brown, Michael; Kobayashi, Katsura;

    2009-01-01

    to the bottom of this nappe date formation of a retrograde sillimanite-bearing penetrative fabric to c. 590 Ma at temperatures of c. 750 degrees C (based on Ti-in-quartz thermometry). Rare zircons from leucosome in high-pressure granulite from the overlying arc-derived nappe yield a Pb-206/U-238 age of 622...

  18. Zircon dating of Neoproterozoic and Cambrian ophiolites in West Mongolia and implications for the timing of orogenic processes in the central part of the Central Asian Orogenic Belt

    Science.gov (United States)

    Jian, Ping; Kröner, Alfred; Jahn, Bor-ming; Windley, Brian F.; Shi, Yuruo; Zhang, Wei; Zhang, Fuqin; Miao, Laicheng; Tomurhuu, Dondov; Liu, Dunyi

    2014-06-01

    We present new isotopic and trace element data to review the geochronological/geochemical/geological evolution of the central part of the Central Asian Orogenic Belt (CAOB), and find a fundamental geological problem in West Mongolia, which has traditionally been subdivided into northwestern early Paleozoic (formerly Caledonian) and southerly late Paleozoic (formerly Hercynian) belts by the Main Mongolian Lineament (MML). We resolve this problem with SHRIMP zircon dating of ophiolites and re-evaluation of much published literature. In Northwest Mongolia the Dariv-Khantaishir ophiolite marks the boundary between the Lake arc in the west and the Dzabkhan-Baydrag microcontinent in the east. Zircons from a microgabbro and four plagiogranites yielded weighted mean 206Pb/238U ages of 568 ± 5 Ma, 567 ± 4 Ma, 560 ± 8 Ma (Dariv), 573 ± 8 Ma and 566 ± 7 Ma (Khantaishir) that we interpret as reflecting the time of ophiolite formation (ca. 573-560 Ma). Metamorphic zircons from an amphibolite on a thrust boundary between the Khantaishir ophiolite and the Dzabkhan-Baydrag microcontinent formed at 514 ± 8 Ma, which we interpret as the time of overthrusting. In South Mongolia the Gobi Altai ophiolite and the Trans-Altai Gurvan Sayhan-Zoolen forearc with an ophiolite basement were investigated. Zircons of a layered gabbro (lower ophiolite crust) and a leucogabbro (mid-upper crust) of the Gobi Altai ophiolite yielded crystallization ages of 523 ± 5 Ma and 518 ± 6 Ma. The age data constrain the formation time of ophiolite within ca. 523-518 Ma. Zircons from four samples of the Gurvan Sayhan-Zoolen forearc, with similar hybrid adakite-boninite affinities, yielded 519 ± 4 Ma for an anorthosite, ≥ 512 ± 4 Ma for a hornblendite and 520 ± 5 and 511 ± 5 Ma for two diorites. The ophiolite basement has an upper age limit of 494 ± 6 Ma, determined by dating a tonalite dike cutting the Zoolen ophiolite. Integrating available zircon ages as well as geochemical and geological data

  19. Zircon (U-Th)/He thermochronometry and modeling of Cenozoic exhumation of the West Spitsbergen Fold Belt: a HeFTy task

    Science.gov (United States)

    Barnes, Chris; Schneider, David; Majka, Jaroslaw; Lorenz, Henning; Kosminska, Karolina; Manecki, Maciej

    2015-04-01

    The West Spitsbergen Fold Belt (WSFB) is part of a ca. 55 Ma Eurekan deformation zone which trends N-S along the western margin of the Svalbard archipelago and is largely comprised of Meso- to Neoproterozoic metasediments and metavolcanics. (U-Th)/He thermochronometry is being conducted from three different regions within the fold belt to resolve the time-temperature history: Wedel Jarlsberg Land, Prins Karls Forland, and Sorkapp Land. Preliminary data obtained from Wedel Jarlsberg Land (amphibolite facies Eimfjellet Group and greenschist facies Sofiebogen Group) yield zircon (U-Th)/He (ZHe) ages indicative of Late Cretaceous to Early Paleogene cooling. It is apparent from the cooling ages that these Neoproterozoic rocks were >200°C before Eurekan deformation. Despite no clear trend between cooling age and grain size, the zircons exhibit a large range of eU values (51 to 826), viewed as a proxy for radiation damage, corresponding to a Gaussian distribution with age. Preliminary ZHe ages obtained from the Macnairrabbane unit of Prins Karls Forland suggests slightly younger cooling, as young as Late Eocene. HeFTy inversion models suggest the possibility that these rocks were at near-surface conditions through much of the Carboniferous and Permian as part of the Sorkapp-Hornsund High as a consequence of the Late Devonian Svalbardian Event. A moderate-temperature burial or heating event is therefore required to explain the Late Cretaceous /Early Paleogene ZHe cooling ages. With the current data, it is difficult to resolve whether this heating event was the result of pre-Eurekan sedimentation or syn-Eurekan over-thrusting. Nonetheless, the data strongly suggest fast cooling (and exhumation) through the He partial-retention zone during Eurekan tectonism, which may have commenced prior to 55 Ma. Similar thermochronometry results have been produced from Mesozoic rocks of the Sverdrup Basin exposed on Axel Heiberg and Ellesmere Islands of Canada; apatite fission-track and

  20. Backscatter Mapping of the West Florida Shelf (Southern Region), Gulf of Mexico (NODC Accession 0001410)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XYZ ASCII format data generated from the 2001 multibeam sonar survey of the West Florida Shelf, Gulf of Mexico. The data include high-resolution bathymetry and...

  1. Bathymetry Mapping of the West Florida Shelf (Southern Region), Gulf of Mexico (NODC Accession 0001410)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XYZ ASCII format data generated from the 2001 multibeam sonar survey of the West Florida Shelf, Gulf of Mexico. The data include high-resolution bathymetry and...

  2. Wetlands Management and risk for West Nile Virus Circulation in Camargue, Southern France

    Science.gov (United States)

    Leblond, Agnes; Pradier, Sophie; Paul, Mathilde; Lecollinet, Sylvie; Sandoz, Alain

    2016-04-01

    West Nile Virus (WNV) is a flavivirus transmitted between mosquitoes (mainly the genus Culex) and wild birds. Horses and humans are incidental hosts and can develop severe neurological disorders. During last decades, the number of WNV cases reported in Europe has increased dramatically. Large outbreaks of increased clinical severity have been reported in parts of Russia, Southern and Eastern Europe. In the Camargue area, WNV outbreaks have been reported in 2000, 2004 and more recently in 2015. We hypothesize that the management of Camargue wetlands could play a key role in the emergence of outbreaks in this area during recent years. WNV transmission requires competent vectors, receptive hosts, and environmental parameters which allow contact between the vectors and the different hosts. The Rhône Delta is known for its landscape of wetlands and its wealth of different bird species. It is also a region where mosquito populations are very abundant. Recent observations have shown that environmental changes, mainly resulting from anthropogenic practices, have had an impact on inter-annual variations in the wetlands and consequently on the abundance of mosquitoes. Water is provided either by rainfall or by a very tight canal network diverted from the river Rhone. Water management is under the control of individual field owners and dependent on its various uses (grazing, rice culture, hunting reserves). This specific management of water resources could play a role in the circulation of WNV in the area. Non-vaccinated horses (n = 1159 from 134 stables) were sampled in 2007 and 2008 in the Camargue area and a serological test was performed to identify a possible contact with the WNV. Environmental variables related to water resources and management were collected through fifteen Landsat images. Areas with open water and flooded vegetation and their variations within a year and between years (2007-08) were quantified for buffers of 2 km radius around the stables. Mean

  3. Pervasive Palaeogene remagnetization of the central Taurides fold-and-thrust belt (southern Turkey) and implications for rotations in the Isparta Angle

    Science.gov (United States)

    Meijers, Maud J. M.; van Hinsbergen, Douwe J. J.; Dekkers, Mark J.; Altıner, Demir; Kaymakcı, Nuretdin; Langereis, Cor G.

    2011-03-01

    The Turkish Anatolide-Tauride block rifted away from the northern margin of Gondwana in the Triassic, which gave way to the opening of the southern Neo-Tethys. By the late Palaeocene to Eocene, it collided with the southern Eurasian margin, leading to the closure of the northern Neo-Tethys ocean. To determine the position of the Anatolide-Tauride block with respect to the African and Eurasian margin we carried out a palaeomagnetic study in the central Taurides belt, which constitutes the eastern limb of the Isparta Angle. The sampled sections comprise Carboniferous to Palaeocene rocks (mainly limestones). Our data suggest that all sampled rocks are remagnetized during the late Palaeocene to Eocene phase of folding and thrusting event, related to the collision of the Anatolide-Tauride block with Eurasia. To further test the possibility of remagnetization, we use a novel end-member modelling approach on 174 acquired isothermal remanent magnetization (IRM) curves. We argue that the preferred three end-member model confirms the proposed remagnetization of the rocks. Comparing our data to the post-Eocene declination pattern in the central Tauride belt, we conclude that our clockwise rotations are in agreement with data from other studies. After combining our results with previously published data from the Isparta Angle (that includes our study area), we have reasons to cast doubt on the spatial and temporal extent of an earlier reported early to middle Miocene remagnetization event. We argue that the earlier reported remagnetized directions from Triassic rocks—in tilt corrected coordinates—from the southwestern Antalya Nappes (western Taurides), are in good agreement with other studies from the area that show a primary origin of their characteristic remanent magnetization. This implies that we document a clockwise rotation for the southwestern Antalya Nappes since the Triassic that is remarkably similar to the post-Eocene (˜40°) rotation of the central Taurides

  4. Paleomagnetism of an east-west transect across the Cascade arc in southern Washington: Implications for regional tectonism

    Science.gov (United States)

    Hagstrum, J.T.; Swanson, D.A.; Evarts, R.C.

    1999-01-01

    Paleomagnetic data from a transect across the Cascade arc in southern Washington were collected to test models of vertical axis rotations for this part of the Pacific Northwest and to provide information on the tectonic history of the St. Helens seismic zone. The 75 site-mean directions are divided into three groups based on isotopic, fission track, and stratigraphic ages. Group 1 consists of samples from rocks deposited between 39 and 30 Ma and shows a mean clockwise vertical axis rotation of 34?? ?? 13??, group 2 consists of samples from rocks deposited be-tween 30 and 24 Ma and shows a mean clockwise rotation of 17?? ?? 11??, and group 3 consists of samples from rocks between 24 and 16 Ma and shows a mean clockwise rotation of 20?? ?? 12??. Although these three values of rotation are statistically indistinguishable at the 95% confidence level, we interpret them in combination with other data to indicate differential rotation across the St. Helens seismic zone (SHZ). The available paleomagnetic data for Eocene-Oligocene rocks west of the seismic zone show clockwise vertical axis rotations of 30?? ?? 8?? and 35?? ?? 9?? consistent with the value for group 1. The rotational values for groups 2 and 3 and the intrusive suite of Kidd Creek (13 Ma), despite their different ages, have similar values east of the SHZ. Comparing these groups of data east and west of the seismic zone indicates a differential rotation of 10?? ?? 3?? across it. In addition, the rates of rotation in southern Washington are similar to those for rocks in the western Cascades of Oregon and indicate that rotational deformation of Miocene age extends northward into southern Washington and eastward into the axis of the arc.

  5. Structural style variation and its impact on hydrocarbon traps in central Fars, southern Zagros folded belt, Iran

    Science.gov (United States)

    Motamedi, Hossein; Sherkati, Shahram; Sepehr, Mohammad

    2012-04-01

    The Fars area is the main target for Permian gas exploration in the Zagros fold belt. It contains approximately 15 percent of the world's proven gas reserves. The geometrical characteristics of the folded structures change dramatically across the N-S trending Gavbandi High. We used seismic profiles, well data, magnetic survey information and field observations to show that thickness variation of the sedimentary pile inherited from basement geometry is the main reason behind structural style variation in this area which occurred during the Zagros folding. Differences in thickness were more significant in Early-Middle Paleozoic time and decreased considerably upward in time. The total thickness of the Lower Paleozoic succession in the eastern side of the Gavbandi High is approximately 40-50% thicker than on the summit of this basement high. Sedimentary pinch-outs through Cretaceous and Tertiary times indicate that the activity of the basement faults decreased but did not stop. The impact on hydrocarbon traps of the pre-folding basin architecture and the differences in the behavior of the sedimentary cover after Miocene folding is discussed and documented.

  6. Assembly of the Pamirs: Age and origin of magmatic belts from the southern Tien Shan to the southern Pamirs and their relation to Tibet

    Science.gov (United States)

    Schwab, M.; Ratschbacher, L.; Siebel, W.; McWilliams, M.; Minaev, V.; Lutkov, V.; Chen, F.; Stanek, K.; Nelson, B.; Frisch, W.; Wooden, J.L.

    2004-01-01

    Magmatic rocks and depositional setting of associated volcaniclastic strata along a north-south traverse spanning the southern Tien Shan and eastern Pamirs of Kyrgyzstan and Tajikistan constrain the tectonics of the Pamirs and Tibet. The northern Pamirs and northwestern Tibet contain the north facing Kunlun suture, the south facing Jinsha suture, and the intervening Carboniferous to Triassic Karakul-Mazar subduction accretion system; the latter is correlated with the Songpan-Garze-Hoh Xi system of Tibet. The Kunlun arc is a composite early Paleozoic to late Paleozoic-Triassic arc. Arc formation in the Pamirs is characterized by ???370-320 Ma volcanism that probably continued until the Triassic. The cryptic Tanymas suture of the southern northern Pamirs is part of the Jinsha suture. A massive ??????227 Ma batholith stitches the Karakul-Mazar complex in the Pamirs. There are striking similarities between the Qiangtang block in the Pamirs and Tibet. Like Tibet, the regional structure of the Pamirs is an anticlinorium that includes the Muskol and Sares domes. Like Tibet, the metamorphic rocks in these domes are equivalents to the Karakul-Mazar-Songpan-Garze system. Granitoids intruding the Qiangtang block yield ???200-230 Ma ages in the Pamirs and in central Tibet. The stratigraphy of the eastern Pshart area in the Pamirs is similar to the Bangong-Nujiang suture zone in the Amdo region of eastern central Tibet, but a Triassic ocean basin sequence is preserved in the Pamirs. Arc-type granitoids that intruded into the eastern Pshart oceanic-basin-arc sequence (???190-160 Ma) and granitoids that cut the southern Qiangtang block (???170-160 Ma) constitute the Rushan-Pshart arc. Cretaceous plutons that intruded the central and southern Pamirs record a long-lasting magmatic history. Their zircons and those from late Miocene xenoliths show that the most distinct magmatic events were Cambro-Ordovician (???410-575 Ma), Triassic (???210-250 Ma; likely due to subduction along the

  7. First data on Sm-Nd isotope systematics of the Kholodnikansk greenstone belt metavolcanites, the Southern Aldan shield

    International Nuclear Information System (INIS)

    The age of the Kholodnikansk greenstone metavolcanites, located in the south of the Southern Aldan shield, is determined through the method of the Sm-Nd dating with the purpose of studying its earth crust constituent segments formation. The obtained metavolcanites isochronous age, equal to 2.41±0.08 billion years testifies to the fact, that the processes of the early proterozoic activation (2.2-2.4 billion years ago) were manifested not only within the limits of the Central-Aldan complex but also in the south of the Aldan shield

  8. Reconstruction and Comparison of P-T Paths in the Andrelândia Nappe System, Southern Brasília Fold Belt, MG

    Directory of Open Access Journals (Sweden)

    Rafael Gonçalves da Motta

    2010-10-01

    Full Text Available The Andrelândia Nappe System consists of three main nappes, from bottom to top: the lower Andrelândia nappe, themiddle Liberdade nappe and the upper Três Pontas-Varginha nappe and associated klippen, Pouso Alto, Aiuruoca, Carvalhosand Serra da Natureza. In the Andrelândia Nappe System, metamorphism increases from north to south and east to west, withthe highest temperatures and pressures recorded in rocks of the Três Pontas-Varginha nappe and associated klippen. Samplesof pelitic and mafic rocks were selected from the three nappes to determine the conditions of metamorphism using the programThermocalc. In this study, peak metamorphic conditions were calculated for the following samples: one sample of theAndrelândia Nappe (688 ± 35 °C and 5.63 ± 0.9 kbar, one sample of the Liberdade Nappe (648 ± 23°C and 7.41 ± 1 kbar, andthree samples of the Carvalhos Klippe (845 ± 53ºC and 15.7 ± 5.2 kbar, and 847 ± 45oC and 13.6 ± 5.8 kbar for two samplesof pelitic granulites respectively, and 854 ± 71ºC and 15 ± 1.4 kbar for one sample of mafic granulite. P-T paths inferred onthe basis of the observed textures are clockwise and typical of collisional belts.

  9. Geochronology of Triassic-Jurassic granitoids in the southern frames of Mongol-Okhotsk fold belt and the principles of early mesozoic granitic formation in the Central and East Asia

    International Nuclear Information System (INIS)

    Results of U-Pb and U-Pb-Th-isotope dating of zircon from biotite and leucocratic granites in the southern frames of the Mongol-Okhotsk fold belt are presented. The similar estimates of the above mentioned granite ages (208±9 and 190±3 mln. years), the granites being referred traditionally to different intrusive complexes, permit defining essentially the scale of the early mesozoic magmatism manifestations in the Central and East Asia

  10. Geologic Controls of Hydrocarbon Occurrence in the Southern Appalachian Basin in Eastern Tennessee, Southwestern Virginia, Eastern Kentucky, and Southern West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Robert D. Hatcher

    2003-05-31

    This report summarizes the first-year accomplishments of a three-year program to investigate the geologic controls of hydrocarbon occurrence in the southern Appalachian basin in eastern Tennessee, southwestern Virginia, eastern Kentucky, and southern West Virginia. The project: (1) employs the petroleum system approach to understand the geologic controls of hydrocarbons; (2) attempts to characterize the T-P parameters driving petroleum evolution; (3) attempts to obtain more quantitative definitions of reservoir architecture and identify new traps; (4) is working with USGS and industry partners to develop new play concepts and geophysical log standards for subsurface correlation; and (5) is geochemically characterizing the hydrocarbons (cooperatively with USGS). First-year results include: (1) meeting specific milestones (determination of thrust movement vectors, fracture analysis, and communicating results at professional meetings and through publication). All milestones were met. Movement vectors for Valley and Ridge thrusts were confirmed to be west-directed and derived from pushing by the Blue Ridge thrust sheet, and fan about the Tennessee salient. Fracture systems developed during Paleozoic, Mesozoic, and Cenozoic to Holocene compressional and extensional tectonic events, and are more intense near faults. Presentations of first-year results were made at the Tennessee Oil and Gas Association meeting (invited) in June, 2003, at a workshop in August 2003 on geophysical logs in Ordovician rocks, and at the Eastern Section AAPG meeting in September 2003. Papers on thrust tectonics and a major prospect discovered during the first year are in press in an AAPG Memoir and published in the July 28, 2003, issue of the Oil and Gas Journal. (2) collaboration with industry and USGS partners. Several Middle Ordovician black shale samples were sent to USGS for organic carbon analysis. Mississippian and Middle Ordovician rock samples were collected by John Repetski (USGS) and

  11. 40Ar/39Ar ages (600-570 Ma of the Serra do Azeite transtensional shear zone: evidence for syncontractional extension in the Cajati area, southern Ribeira belt

    Directory of Open Access Journals (Sweden)

    Rômulo Machado

    2007-12-01

    Full Text Available This paper presents 40Ar/39Ar ages of the rocks from the Serra do Azeite transtensional shear zone in the southern part of the Ribeira belt, between the States of São Paulo and Paraná, and also discusses the regional correlations and the tectonic implications for other parts of the belt. The geochronological data suggest that transtensional deformation was active between 600 and 580 Ma (hornblende and muscovite apparent ages, respectively. This time span is considerably older than previous proposals for the period of activity of these structures (520-480 Ma in the northern segment of this belt and in the Araçuaí belt. Kinematic analysis of the dated mylonites shows extensional structures with top-down movement to ESE compatible with structures found in other tectonic segments in the eastern portion of the Quadrilátero Ferrífero and in the Rio Doce Valley region. Our ages are situated in the same time interval defined for the alkaline magmatism of the Serra do Mar suite. We suggest that the regional tectonic framework was developed during continental-scale extension. This process has been coeval with convergent strain in the adjacent Neoproterozoic shear zones of the Apiaí/Ribeira and Araçuaí belts, which make up significant segments of these belts. The available data show that these structures may not be simply related to post-orogenic gravitational collapse, but must involve a more complex process probably related to dynamic balance between crustal thickening and thinning during tectonic convergence, basin formation and exhumation processes.Este trabalho apresenta idades 40Ar/39Ar de rochas da Zona de Cisalhamento Transtrativa Sinistral da Serra do Azeite, situada na parte sul do cinturão Ribeira, entre os Estados de São Paulo e Paraná, bem como discute a correlação regional e as implicações tectônicas com outras partes do cinturão. Os dados geocronológicos sugerem que a deformação extensional foi ativa entre 600 e 580 Ma

  12. Structural control on gold mineralization in the Satulinmäki and Riukka prospects, Häme Schist Belt, southern Finland

    Directory of Open Access Journals (Sweden)

    Kerstin Saalmann

    2007-01-01

    Full Text Available The Satulinmäki and Riukka prospects located in the Häme Schist Belt in southern Finland are dominated by mafic and intermediate to felsic metavolcanic rocks of the Forssa Group formed in a continental arc setting. This magmatic belt formed some 1890–1880 Ma ago and has been deformed during the Svecofennian orogeny. The dominant penetrative foliation is represented by Sn+1, which is axial planar to cm- to dm-scale iscolinal Fn+1 folds and thus parallel to the layering Sn. Associated ductile shearing might reflect early thrusting. Dn+2 post-dating peak metamorphism is characterized by small-scale to regional-scale refolding of Fn+1 folds around ~SW-NE fold axes. This phase is transitional to development of SW-NE to WSW-ENE and NW-SE striking shear zones and faults formed due to dextral transpressionduring Dn+3 at retrograde conditions crossing the brittle-ductile transition. Many mineralized quartz veins have formed during this event. Later faults and quartz veins and reactivation of pre-existing structures during Dn+4 indicate rotation of the stress field to ~NESWoriented compression. A clear ~SW-NE trend of sulphide mineralization and elevated gold contents and the spatial association to Dn+3 quartz veins, shear zones and faults suggest a strong structural control, typical of orogenic gold deposits, and that mineralization took place during Dn+3. The controlling structures, (i WSW-ENE to SW-NE shear zones and faults and (ii NW-SE oriented fault, are second and third order structures to major regional-scale shear zones. The fault zones and their intersection points impart a directional permeability so that the mineralising fluids were channelled along dilatant zones. Approximately (WNW-(ESE trending faults being (reactivated as extensional faults or dilatant shear planes during Dn+3 transpression with WNW-ESE to NW-SE oriented compression direction could have acted as conduits for fluids during upward flow from deeper crustal level. Future

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

    Science.gov (United States)

    Brew, David A.; Morrell, Robert P.

    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

  14. Petrogenesis of Cretaceous adakite-like intrusions of the Gangdese Plutonic Belt, southern Tibet: Implications for mid-ocean ridge subduction and crustal growth

    Science.gov (United States)

    Zheng, Yuan-chuan; Hou, Zeng-qian; Gong, Ying-li; Liang, Wei; Sun, Qing-Zhong; Zhang, Song; Fu, Qiang; Huang, Ke-Xian; Li, Qiu-Yun; Li, Wei

    2014-03-01

    least 70% of the magma source region was juvenile materials. Combined with the presence of HT (high temperature) charnockitic magmatism, HT granulite facies metamorphism, and large volumes of Late Cretaceous batholiths, the oceanic-slab-derived Nuri adakitic rocks indicate a substantial high heat flux in the Gangdese batholith belt during the Late Cretaceous, which may have been related to subduction of a Neo-Tethyan mid-ocean ridge system. According to this model, hot asthenosphere would rise up through the corresponding slab window, and come into direct contact with both the oceanic slab and the base of the overlying plate. This would cause melting of both the oceanic slab and the overlying plate by the addition of heat that was ultimately linked with peak magmatism and the significant growth and chemical differentiation of juvenile crust in southern Tibet during the Late Cretaceous (105-76 Ma). In addition, the petrogenesis of the Langxian adakite-like two-mica granite indicates that the southern Tibetan crust was still of normal thickness prior to the emplacement of these intrusions at ca. 76 Ma. This probably means that large parts of southern Tibet were not very highly elevated prior to the Indian-Asian collision.

  15. Using blue-ice moraines to constrain elevation changes of the West Antarctic Ice Sheet in the southern Ellsworth Mountains

    Science.gov (United States)

    Sugden, David; Woodward, John; Dunning, Stuart; Hein, Andy; Marrero, Shasta; Le-Brocq, Anne

    2014-05-01

    Observations in the Weddell Sea sector of the Antarctic Ice Sheet have not yet allowed the dating of elevated glacier trimlines and associated deposits in the Ellsworth Mountains. This uncertainty limits the value of models of changing ice-sheet configuration, volume and, by extension, sea level during glacial cycles and earlier. Here we present the emerging results of a study into the origin and evolution of blue-ice moraines in the Heritage Range, southern Ellsworth Mountains, and begin to unravel the long record of ice-sheet history they hold. Our findings so far are: (a) Ground Penetrating Radar shows that the blue-ice moraines are equilibrium forms bringing basal debris to the ice surface; the compressive ice flow is caused by enhanced ablation at the mountain foot. (b) Moraines are concentrated in embayments that focus katabatic winds and their location is largely controlled by topography. (c) The elevated blue-ice moraines in the southern Ellsworth Mountains hold a continuous record of West Antarctic Ice Sheet history going back 600,000 years; so far we have not found evidence of de-glacial intervals. (d) Thinning since the LGM (~40 ka?) is blue-ice moraine formation.

  16. Pre-1.91 Ga deformation and metamorphism in the Palaeoproterozoic Vammala Migmatite Belt, southern Finland, and implications for Svecofennian tectonics

    Directory of Open Access Journals (Sweden)

    R. W. Roye Rutland

    2004-01-01

    Full Text Available A metamorphic event in the Vammala Migmatite Belt (VMB at ~1.92 Ga, revealed by SHRIMP U-Pb analyses of both zircon overgrowths and monazite, is interpreted as post-depositional and is correlated with the development of the early high-grade schistosity. Neither this Early Svecofennian deformation and metamorphism, nor the associatedcomplex folding, is present in the overlying Tampere Schist Belt (TSB sequence, consistent with the VMB being part of a pre-1.91 Ga basement complex. The ~1.92 Ga event provides a maximum deposition age for the TSB, confirming earlier age estimates. Earlier stratigraphic correlations between parts of the VMB and TSB, and associated tectonic interpretations, can no longer be sustained. The crustal thickening seen in the VMB, and previously attributed to arc accretion at ~1.89 Ga, is now attributed to accretion of a large Svionian marginal basin during the ‘Early Svecofennian’ orogenicphase at ~1.92 Ga. This is of similar age to the deformation and metamorphism associated with collision in the Lapland-Kola Orogen to the north of the Karelian Province. The well-known post-TSB orogenic phase was also identified in the VMB by a monazite age of 1881±6 Ma. A granitoid intrusion gave an emplacement age of 1888±5 Ma,comparable to the age of granitoid clasts in the upper part of the TSB succession. The detrital zircon data are interpreted to suggest that deposition of the precursor VMB sediments probably took place soon after an earlier pre-depositional metamorphism at ~1.98 Ga, which affected igneous source complexes dated at ~1.99 Ga and ~2.01 Ga. Mafic rocks in the southern part of the VMB, and probably also the Haveri basalts, represent a renewed episode of extensional magmatism, which might correlate with the 1.96–1.95 Ga Jormua and Outokumpu ophiolites. A pre-1.96 Ga older stage basin has an expression in Sweden and complexes of similar age occur in theconcealed Palaeoproterozoic basement south of the Gulf of

  17. Shallow structure of the Chichinautzin Range, southern Mexico basin, central Trans-Mexican Volcanic Belt. A gravity and seismic study

    Science.gov (United States)

    Campos-Enriquez, J. O.; Lermo-Samaniego, J. F.; Antahyua-Vera, Y. T.; Chavacan, M.; Ramón, V. M.; Hernández-García; Pita, C.

    2013-12-01

    Chichinautzin Range (ChR) closes to the S the Mexico Basin (MB). Initially based on height differences between MB and the to-he S-located Morelos Plataform (MP) , a major S-dipping fault was proposed. Depths differences to the limestone basement beneath MB and MP respectively supported its existence. This assumed fault was named La Pera. Earlier studies reported the existence of several faults affecting the ChR. New studies were focused to analyze the cinematic and dynamic character of faults to the W of ChR (Tenango Fault System) and of southern Sierra de la Cruces Range. Also based on a gravity study (Campos-Enríquez et al., 2000), the existence of a major N-dipping fault was inferred to delimit the MB to the S (i.e., delimiting the ChR to the N). Our study is based on gravity modelling, and local seismicity analysis. Accordingly, Mezosoic sandstones above metamorphic rocks constitute the basement underlying ChR. This structural high is faulted to the N and S. To the N, fault blocks displace the basement to larger depths (2-4 km). To the S the basement is shallower. The faults of the gravity model correlate with all reported faults, which collectively are refferred to as Aztlan Fault System. Two N-S MT profiles confirm the model. Several of these faults are associated with seismic activity with a N-S extension and a left-lateral component. The seismic event were located at depths of 7-15 km (i.e. the brittle crust). The system can be traced from the Nevado de Tolca volcano up to the Popocatépetl volcano and even further eastwards. The system is about 200 km long, 30-40 km wide, tectonically active. It enabled the fast emplacement of the ChR volcanic rocs. A flower-type structure was inferred to the S of ChR, further south, the profile is cut by faults belonging either to the Taxco-San Miguel de Allende Fault System or to the Chapala-Oaxaca Fault System. This profile shows how the transpressive tectonics, to the S, accomodates, with the N-S extension affecting

  18. Runic Inscriptions Reflecting Linguistic Contacts between West Slav Lands and Southern Scandinavia

    OpenAIRE

    Lerche Nielsen, Michael

    2014-01-01

    This article discusses the discrepancy between historical accounts of the contacts between Scandinavians and West Slavs in the late Viking Age and early Middle Ages on the one hand and linguistic evidence — loan words, place-names, personal names, and runic inscriptions — on the other. The main focus is the small corpus of runic inscriptions found in urban contexts along the south coast of the Baltic Sea. The inscriptions were previously seen as signs of hostilities, but the finds from Starig...

  19. Postglacial paleoenvironmental history of the Southern Patagonian Fjords at 53°S

    OpenAIRE

    Francois, Jean-Pierre

    2014-01-01

    Southern Patagonia (50°-56°S) is as key region for paleoenvironmental studies, in particular, for addressing fundamental paleoclimatic and paleoecological questions. This is due to a number of physical and biotic characteristics of the region: (i) its location allows to examine and reconstruct changes of the Southern Westerly Wind (SWW) belt, (ii) the presence of the Andes, which intercepts the flux of the SWWs creating a strong orographic precipitation gradient on a west-east axis, and (iii)...

  20. Tropical West Pacific moisture dynamics and climate controls on rainfall isotopic ratios in southern Papua, Indonesia

    Science.gov (United States)

    Permana, Donaldi S.; Thompson, Lonnie G.; Setyadi, Gesang

    2016-03-01

    Understanding the controls on stable isotopologues of tropical rainfall is critical for paleoclimatic reconstruction from tropical ice core records. The southern Papua region, Indonesia, has a unique climate regime that allows for the evaluation of the influence of precipitation and convective activity on seasonal rainfall δ18O. The influence of the El Niño-Southern Oscillation (ENSO) on interannual rainfall δ18O variation is also important for paleoclimate reconstruction. Here we present stable isotope analyses of 1332 rain samples collected daily during the period from January 2013 to February 2014 (ENSO-normal) and December 2014 to September 2015 (El Niño) at various elevation stations (9 to 3945 m above sea level) on the southern slope of the central mountain ranges in Papua. The results suggest an altitude effect with an isotopic lapse rate for δ18O (δD) of -2.4‰/km (-18.2‰/km). The temporal δ18O variability (daily to interannual) is controlled mostly by regional convective activity rather than local/regional precipitation amount. The intraseasonal δ18O variation resembles the Madden-Julian Oscillation cycle with major δ18O depletion events associated with active (wet) phases. Moisture origins, transport pathways, moisture convergence, and raindrop evaporation appear to have no significant seasonal effects on δ18O, leading to the conclusion that condensation temperature controls δ18O depletion associated with convective activity. Seasonal δ18O variation is likely associated with atmospheric temperature at the mean condensation level as indicated by the altitude of latent heat release in the troposphere. Rainfall δ18O (δD) is generally enriched by 1.6‰-2‰ (11‰-15‰) during El Niño than during ENSO-normal periods.

  1. Holocene Southern Ocean surface temperature variability west of the Antarctic Peninsula.

    Science.gov (United States)

    Shevenell, A E; Ingalls, A E; Domack, E W; Kelly, C

    2011-02-10

    The disintegration of ice shelves, reduced sea-ice and glacier extent, and shifting ecological zones observed around Antarctica highlight the impact of recent atmospheric and oceanic warming on the cryosphere. Observations and models suggest that oceanic and atmospheric temperature variations at Antarctica's margins affect global cryosphere stability, ocean circulation, sea levels and carbon cycling. In particular, recent climate changes on the Antarctic Peninsula have been dramatic, yet the Holocene climate variability of this region is largely unknown, limiting our ability to evaluate ongoing changes within the context of historical variability and underlying forcing mechanisms. Here we show that surface ocean temperatures at the continental margin of the western Antarctic Peninsula cooled by 3-4 °C over the past 12,000 years, tracking the Holocene decline of local (65° S) spring insolation. Our results, based on TEX(86) sea surface temperature (SST) proxy evidence from a marine sediment core, indicate the importance of regional summer duration as a driver of Antarctic seasonal sea-ice fluctuations. On millennial timescales, abrupt SST fluctuations of 2-4 °C coincide with globally recognized climate variability. Similarities between our SSTs, Southern Hemisphere westerly wind reconstructions and El Niño/Southern Oscillation variability indicate that present climate teleconnections between the tropical Pacific Ocean and the western Antarctic Peninsula strengthened late in the Holocene epoch. We conclude that during the Holocene, Southern Ocean temperatures at the western Antarctic Peninsula margin were tied to changes in the position of the westerlies, which have a critical role in global carbon cycling. PMID:21307939

  2. Guangxi West River Economic Belt City Groups’Development Strategy in View of Ecological Niche%生态位视角下广西西江经济带城市群发展策略

    Institute of Scientific and Technical Information of China (English)

    黄河东

    2012-01-01

    从城市经济生态位、人口生态位、环境生态位三个方面选择15项指标,运用城市生态位的评估方法就可以确定广西西江经济带城市群的生态位及其特征。据此可知,广西西江经济带城市群发展的政策应按照生态位分离策略、生态位扩充策略、生态位共生策略等方面的要求去制订。%The article chooses 15 indexes from the city economic ecological niche,population ecological niche and environment ecological niche,and uses the city economic niche assessment methods to determine city groups' ecological niche and features in Guangxi West River economic belt.So it is found that the development policy of the city groups in Guangxi West River economic belt should be made based on the coexisting ecological niche separation strategies,ecological niche expansion strategy and ecological niche symbiosis strategy.

  3. Sphagnum peatland development at their southern climatic range in West Siberia: trends and peat accumulation patterns

    Energy Technology Data Exchange (ETDEWEB)

    Peregon, Anna [Center for Global Environmental Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Uchida, Masao [Environmental Chemistry Division, NIES-TERRA AMS Facility, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Shibata, Yasuyuki [Environmental Chemistry Division, NIES-TERRA AMS Facility, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan)

    2007-10-15

    A region of western Siberia is vulnerable to the predicted climatic change which may induce an important modification to the carbon balance in wetland ecosystems. This study focuses on the evaluation of both the long-term and contemporary trends of peat (carbon) accumulation and its patterns at the southern climatic range of Sphagnum peatlands in western Siberia. Visible and physical features of peat and detailed reconstructions of successional change (or sediment stratigraphies) were analysed at two types of forest-peatland ecotones, which are situated close to each other but differ by topography and composition of their plant communities. Our results suggest that Siberian peatlands exhibit a general trend towards being a carbon sink rather than a source even at or near the southern limit of their distribution. Furthermore, two types of peat accumulation were detected in the study area, namely persistent and intermittent. As opposed to persistent peat accumulation, the intermittent one is characterized by the recurrent degradation of the upper peat layers at the marginal parts of raised bogs. Persistent peat accumulation is the case for the majority of Sphagnum peatlands under current climatic conditions. It might be assumed that more peat will accumulate under the 'increased precipitation' scenarios of global warming, although intermittent peat accumulation could result in the eventual drying that may change peatlands from carbon sinks to carbon sources.

  4. Sphagnum peatland development at their southern climatic range in West Siberia: trends and peat accumulation patterns

    International Nuclear Information System (INIS)

    A region of western Siberia is vulnerable to the predicted climatic change which may induce an important modification to the carbon balance in wetland ecosystems. This study focuses on the evaluation of both the long-term and contemporary trends of peat (carbon) accumulation and its patterns at the southern climatic range of Sphagnum peatlands in western Siberia. Visible and physical features of peat and detailed reconstructions of successional change (or sediment stratigraphies) were analysed at two types of forest-peatland ecotones, which are situated close to each other but differ by topography and composition of their plant communities. Our results suggest that Siberian peatlands exhibit a general trend towards being a carbon sink rather than a source even at or near the southern limit of their distribution. Furthermore, two types of peat accumulation were detected in the study area, namely persistent and intermittent. As opposed to persistent peat accumulation, the intermittent one is characterized by the recurrent degradation of the upper peat layers at the marginal parts of raised bogs. Persistent peat accumulation is the case for the majority of Sphagnum peatlands under current climatic conditions. It might be assumed that more peat will accumulate under the 'increased precipitation' scenarios of global warming, although intermittent peat accumulation could result in the eventual drying that may change peatlands from carbon sinks to carbon sources

  5. Land cover, landscape structure, and West Nile virus circulation in southern France.

    Science.gov (United States)

    Pradier, S; Leblond, A; Durand, B

    2008-04-01

    The transmission of West Nile virus (WNV) is strongly influenced by environmental factors. In France, two endemic areas for WNV have been identified: Camargue and Var. The objective of our study was to test whether landscape characteristics could be associated with the risk of endemic circulation of WNV in these two ecologically different areas. Equine serological data collected during outbreaks in Var (2003) and Camargue (2004) were used. Both areas were marked out in cells of 5 km(2), and data were aggregated for each cell. Sixteen cells, classified as "high" level viral circulation, and 28 cells, classified as "low" level viral circulation were used for the analysis. The Corine Land Cover database (European Environment Agency) was used to evaluate, for each geographic cell, the area covered by 12 land cover classes, as well as the value of 5 landscape metrics (patch richness and density, edge density, the Shannon's diversity index, and interspersion and juxtaposition index (IJI). Multivariate linear generalized regression showed that IJI as well as the surface covered by heterogeneous agricultural areas were significantly higher in high level WNV circulation cells than in low level ones (p = 0.01 and 0.05 respectively). Both variables are indicators of a complex spatial biotope configuration that may favor the co-existence of competent vectors and reservoir hosts: the structure of the landscape thus appeared as a key element in WNV circulation. An internal validation was performed and the model was used to compute a risk map for the French Mediterranean coast. Cells with a probability > 0.8 of having a high level of viral circulation were found near Aix-en-Provence, Beziers, and Perpignan, areas where no serological study has yet been conducted. Equine cases reported in 2006 were all located in the neighborhood of cells having a > 0.8 probability for high WNV circulation status. PMID:18429693

  6. Chronic Diseases in North-West Tanzania and Southern Uganda. Public Perceptions of Terminologies, Aetiologies, Symptoms and Preferred Management.

    Directory of Open Access Journals (Sweden)

    Soori Nnko

    Full Text Available Research has shown that health system utilization is low for chronic diseases (CDs other than HIV. We describe the knowledge and perceptions of CDs identified from rural and urban communities in north-west Tanzania and southern Uganda.Data were collected through a quantitative population survey, a quantitative health facility survey and focus group discussions (FGDs and in-depth interviews (IDIs in subgroups of population survey participants. The main focus of this paper is the findings from the FGDs and IDIs.We conducted 24 FGDs, involving approximately 180 adult participants and IDIs with 116 participants (≥18 years. CDs studied included: asthma/chronic obstructive lung disease (COPD, diabetes, epilepsy, hypertension, cardiac failure and HIV- related disease. The understanding of most chronic conditions involved a combination of biomedical information, gleaned from health facility visits, local people who had suffered from a complaint or knew others who had and beliefs drawn from information shared in the community. The biomedical contribution shows some understanding of the aetiology of a condition and the management of that condition. However, local beliefs for certain conditions (such as epilepsy suggest that biomedical treatment may be futile and therefore work counter to biomedical prescriptions for management.Current perceptions of selected CDs may represent a barrier that prevents people from adopting efficacious health and treatment seeking behaviours. Interventions to improve this situation must include efforts to improve the quality of existing health services, so that people can access relevant, reliable and trustworthy services.

  7. Late Cretaceous (ca. 90 Ma) adakitic intrusive rocks in the Kelu area, Gangdese Belt (southern Tibet): Slab melting and implications for Cu-Au mineralization

    Science.gov (United States)

    Jiang, Zi-Qi; Wang, Qiang; Li, Zheng-Xiang; Wyman, Derek A.; Tang, Gong-Jian; Jia, Xiao-Hui; Yang, Yue-Heng

    2012-07-01

    The Gangdese Belt in southern Tibet (GBST) is a major Cu-Au-Mo mineralization zone that mostly formed after the India-Asia collision in association with the small-volume, though widespread, Miocene (18-10 Ma) adakitic porphyries. Cu-Au mineralization has scarcely been found in the regional Jurassic-Early Tertiary batholiths related to subduction of the Neo-Tethyan oceanic plate. Here, we report petrological, zircon geochronological and geochemical data for Late Cretaceous (˜90 Ma) intrusive rocks that contain Cu-Au mineralization from the Kelu area in the GBST. These rocks consist of quartz monzonites and diorites. The quartz monzonites, with SiO2 of 58-59 wt.% and Na2O/K2O of 1.1-1.2, are geochemically similar to slab-derived adakites characterized by apparent depletions in heavy rare earth elements (e.g., Yb = 1.4-1.5 ppm) and Y (16-18 ppm) contents, positive Sr but negative Nb and Ti anomalies on multi-element variation diagrams. They have relatively low (87Sr/86Sr)i (0.7038-0.7039) ratios and high ɛNd(t) (+3.4 to +3.9) and in situ zircon ɛHf(t) (+9.3 to +15.8) values. The diorites exhibit high Mg-numbers (0.57-0.61) similar to those of magnesian andesites, and have (87Sr/86Sr)i (0.7040-0.7041) and ɛNd(t) (+3.0 to +4.4) values similar to those of the quartz monzonites. We suggest that the quartz monzonitic magmas were most likely generated by partial melting of the subducted Neo-Tethyan basaltic oceanic crust and minor associated oceanic sediments, with subsequent melt-mantle interaction, and the dioritic magmas were mainly derived by the interaction between slab melts and mantle wedge peridotites, with fractionation of apatite and hornblende. These slab-derived adakitic magmas have high oxygen fugacity that may have facilitated Cu-Au mineralization. The close association of the Late Cretaceous adakitic intrusive rocks and Cu-Au mineralization in the Kelu area suggests that the arc magmatic rocks in the GBST may have higher potential than previously thought

  8. Carbon Dynamics of Bioenergy Cropping Systems Compared to Conventional Cotton Cropping Systems in the Southern Cotton Belt Region of the U.S.

    Science.gov (United States)

    Rajan, N.; Sharma, S.; Casey, K.; Maas, S. J.

    2015-12-01

    We are facing an unprecedented challenge in securing America's energy future. To address this challenge, increased biofuel crop production is needed. Second-generation biofuels are made from the by-products of intensive agriculture or from less-intensive agriculture on more marginal lands. The Southwestern U.S. Cotton Belt can play a significant role in this effort through a change from more conventional crops (like continuous cotton) to second-generation biofuel feedstocks (biomass sorghum and perennial grasses). We have established eddy covariance flux towers in producer fields in the Southern High Plains region. Among the four land uses compared, the net carbon uptake was the highest for the biomass sorghum field. During the year 2014, the biomass sorghum field gained approximately 672 gC m-2y-1. The next highest carbon uptake was recorded for the Old World Bluestem grass field, which was approximately 301 gC m-2y-1. The dominant land use in the region is cotton. While the forage sorghum and grass fields acted as net carbon sinks, the irrigated cotton field acted as a net carbon source to the atmosphere during the same period. The irrigated cotton field exhibited a net carbon loss of approximately 246 gC m-2y-1. In contrast, the dryland cotton field acted as a net carbon sink, with a total uptake of approximately 58 g C m-2y-1. The net primary production of the irrigated cotton field was higher than that of the dryland cotton field, yet the irrigated field was a significant carbon source to the atmosphere. This was due to conventional tillage practices combined with irrigation which enhanced the ecosystem respiration significantly compared to the dryland field. In 2014, an early spring cold front caused poor germination of seeds in the majority of the cotton fields in the region, including the eddy covariance site. This site was re-planted on 9 June, which shortened the growing season for cotton. This was also a contributing factor to this field being a net

  9. Correlation of Coseismic Velocity and Static Volumetric Strain Changes Induced by the 2010 Mw6.3 Jiasian Earthquake under the Southern Taiwan Orogenic Belt

    Science.gov (United States)

    Wu, S. M.; Hung, S. H.

    2015-12-01

    Earthquake-induced temporal changes in seismic velocity of the earth's crust have been demonstrated to be monitored effectively by the time-lapse shifts of coda waves recently. Velocity drop during the coseismic rupture has been explicitly observed in proximity to the epicenters of large earthquakes with different styles of faulting. The origin of such sudden perturbation in crustal properties is closely related to the damage and/or volumetric strain change influenced by seismic slip distribution. In this study, we apply a coda wave interferometry method to investigate potential velocity change in both space and time related to the moderate-sized (Mw6.3) 2010 Jiasian earthquake, which nucleated deeply in the crust (~23 km), ruptured and terminated around the depth of 10 km along a previously unidentified blind thrust fault near the lithotectonic boundary of the southern Taiwan orogenic belt. To decipher the surface and crustal response to this relatively deep rupture, we first measure relative time-lapse changes of coda between different short-term time frames spanning one year covering the pre- and post-seismic stages by using the Moving Window Cross Spectral Method. Rather than determining temporal velocity variations based on a long-term reference stack, we conduct a Bayesian least-squares inversion to obtain the optimal estimates by minimizing the inconsistency between the relative time-lapse shifts of individual short-term stacks. The results show the statistically significant velocity reduction immediately after the mainshock, which is most pronounced at the pairs with the interstation paths traversing through the hanging-wall block of the ruptured fault. The sensitivity of surface wave coda arrivals mainly in the periods of 3-5 s to shear wave speed perturbation is confined within the depth of 10 km, where the crust mostly experienced extensional strain changes induced by the slip distribution from the finite-fault model. Compared with coseismic slip

  10. Wetland Expansion on the Southern Edge of the West Siberian Sphagnum Wetlands

    Science.gov (United States)

    Peregon, A.

    2006-12-01

    The southern border of Vasyugan wetland was chosen to analyse the long term trend in organic carbon (peat) accumulation and wetland expansion processes. In our study, the comprehensive field (soil/peat and geobotanical) studies were conducted and the results were extrapolated using Landsat ETM+ satellite images. Two types of interaction (ecotones) between forest and wetland were revealed within the study area. Variations in the trend of peat accumulation were found in two types of ecotones, strongly affected by topography and chemical properties of the mineral subsoil of wetland basin. One ecotone is represented by a range of forest ecosystems on flat terrain, and differs from another by the absence of reed communities. Flat topography, coupled with loamy structure and poorness of the subsoil provide conditions for the "permanent" formation of wetlands in the forest ecotone. Progression of the Sphagnum wetlands toward the adjoining deciduous forests was confirmed by existence of the residual soils, recently covered by peat sediments. Another, forest-reeds ecotone is situated on the more uneven terrain providing the path for water flow from the periphery of wetland basin. This causes the recurrence of drying and wetting of upper peat layers, resulting in the fluctuation in the carbon-storage capability of the area and recurring peat degradation on the periphery of peatland basin. The reed ecosystems are the sure indicator of carbonates located close to the land surface. The high concentration of carbonates in subsoil inhibits the advance of Sphagnum mosses and subsequent expansion of wetlands (i.e. "intermittent" wetland formation). Finally, the forest wetland boundary areas on the satellite images were classified into different types of ecotones described earlier. The final layout, prepared in the scale of 1:200K, demonstrates the evident activity of the wetland expansion processes even in the relatively dry climate without excess of precipitation over evaporation

  11. IDENTIFICATION OF URBAN HEAT ISLANDS FROM MULTI TEMPORAL MODIS LAND SURFACE TEMPERATURE DATA IN THE SOUTHERN PART OF WEST BENGAL, INDIA

    OpenAIRE

    Naval Kishore Yadav *, Abhisek Santra, Amiya Kumar Samanta

    2016-01-01

    Land surface temperature is the temperature of the earth’s ground surface and is crucial for climate studies in different aspects like geology, engineering, phenology etc. Research on urban heat island is mainly dependent upon the land surface temperature studies and is highly useful from civil engineering perspective. An attempt has been made here to study the spatio-temporal dynamics of the land surface temperature and associated urban heat islands in the southern part of West Bengal,...

  12. Spatial and temporal dynamics of sediment in contrasted mountainous watersheds (Mexican transvolcanic belt and French Southern Alps) combining river gauging, elemental geochemistry and fallout radionuclides

    Science.gov (United States)

    Evrard, O.; Navratil, O.; Gratiot, N.; Némery, J.; Duvert, C.; Ayrault, S.; Lefèvre, I.; Legout, C.; Bonté, P.; Esteves, M.

    2009-12-01

    In mountainous environments, an excessive fine sediment supply to the rivers typically leads to an increase in water turbidity, contaminant transport and a rapid filling of reservoirs. This situation is particularly problematic in regions where water reservoirs are used to provide drinking water to large cities (e.g. in central Mexico) or where stream water is used to run hydroelectric power plants (e.g. in the French Southern Alps). In such areas, sediment source areas first need to be delineated and sediment fluxes between hillslopes and the river system must be better understood before implementing efficient erosion control measures. In this context, the STREAMS (« Sediment Transport and Erosion Across MountainS ») project funded by the French National Research Agency (ANR) aims at understanding the spatial and temporal dynamics of sediment at the scale of mountainous watersheds (between 500 - 1000 km2) located in contrasted environments. This 3-years study is carried out simultaneously in a volcanic watershed located in the Mexican transvolcanic belt undergoing a subhumid tropical climate, as well as in a sedimentary watershed of the French Southern Alps undergoing a transitional climate with Mediterranean and continental influences. One of the main specificities of this project consists in combining traditional monitoring techniques (i.e. installation of river gauges, turbidimeters and sediment samplers in several sub-catchments) and sediment fingerprinting using elemental geochemistry (measured by Instrumental Neutron Activation Analysis - INAA - and Inductively Coupled Plasma - Mass Spectrometry - ICP-MS) and fallout radionuclides (measured by gamma spectrometry). In the French watershed, geochemical analysis allows outlining different sediment sources (e.g. the contribution of calcareous vs. marl-covered sub-watersheds). Radionuclide ratios (e.g.Be-7/Cs-137) allow identifying the dominant erosion processes occurring within the watershed. Areas mostly

  13. A comparison of the radio data and model calculations of Jupiter's synchrotron radiation. I - The high energy electron distribution in Jupiter's inner magnetosphere. II - East-west asymmetry in the radiation belts as a function of Jovian longitude

    Science.gov (United States)

    De Pater, I.

    1981-01-01

    A comparison has been made between detailed model calculations of Jupiter's synchrotron radiation and the radio data at wavelengths of 6, 21, and 50 cm. The calculations were performed for a Jovian longitude of 200 deg and were based on the multipole field configurations as derived from the Pioneer data. The electron distribution in the inner magnetosphere was derived as a function of energy, pitch angle, and spatial coordinates. In addition, the hot region or east-west asymmetry in the radiation belts is investigated. It is suggested that this asymmetry is due to the combined effect of an overabundance of electrons at jovicentric longitudes of 240-360 deg and the existence of a dusk-to-dawn directed electric field over the inner magnetosphere generated by the wind system in the upper atmosphere.

  14. Cave bats of the central west coast and southern section of the Northwest Panay Peninsula, Panay Island, the Philippines

    Directory of Open Access Journals (Sweden)

    A. Mould

    2012-09-01

    Full Text Available Bats (order Chiroptera form a large proportion of the species-rich mammalian fauna of the Philippines, and while the threats posed to these animals are well documented, for many species there is currently insufficient data to enable even a basic assessment of their conservation status. This is true for Panay Island, located in the Western Visayas region of the archipelago, where the need for surveying remaining suitable bat habitat has been identified as a priority. Between 5 April and 9 May 2011 a survey of 21 caves was undertaken on Panay, along the central section of the west coast of the island and within the southern section of the Northwest Panay Peninsula. Survey methods included visual observations, emergence counts and the recording of echolocation calls. Of the caves surveyed, 19 were found to support bats or show signs of their use, and at least 12 different species were observed. Three large maternity colonies of the Common Rousette Rousettus amplexicaudatus and two of the Dusky Roundleaf Bat Hipposideros ater were noted as having particular significance in terms of their conservation value for local populations. Potential maternity colonies of Asian Lesser False Vampire Megaderma spasma, Black-bearded Tomb Bat Taphozous melanopogon and Diadem Roundleaf Bat Hipposideros diadema were also observed but not confirmed. M. spasma was the most frequently encountered species, occurring in small numbers at five different caves. Other species/genera encountered in small numbers were the Arcuate Horseshoe Bat Rhinolophus arcuatus, Common Short-nosed Fruit Bat Cynopterus brachyotis, Philippine Sheath-tailed Bat Emballonura alecto, Yellow-faced Horseshoe Bat Rhinolophus virgo, Bent-wing (Miniopterus and Myotis bat species, and at least one other Horseshoe (Rhinolophus bat species. Ten of the caves were confirmed to support multiple bat species. An indication of current threats and recommendations for further survey and management priorities are

  15. Metamorphic belts of Anatolia

    Science.gov (United States)

    Oberhänsli, Roland; Prouteau, Amaury; Candan, Osman; Bousquet, Romain

    2015-04-01

    Investigating metamorphic rocks from high-pressure/low-temperature (HP/LT) belts that formed during the closure of several oceanic branches, building up the present Anatolia continental micro-plate gives insight to the palaeogeography of the Neotethys Ocean in Anatolia. Two coherent HP/LT metamorphic belts, the Tavşanlı Zone (distal Gondwana margin) and the Ören-Afyon-Bolkardağ Zone (proximal Gondwana margin), parallel their non-metamorphosed equivalent (the Tauride Carbonate Platform) from the Aegean coast in NW Anatolia to southern Central Anatolia. P-T conditions and timing of metamorphism in the Ören-Afyon-Bolkardağ Zone (>70?-65 Ma; 0.8-1.2 GPa/330-420°C) contrast those published for the overlying Tavşanlı Zone (88-78 Ma; 2.4 GPa/500 °C). These belts trace the southern Neotethys suture connecting the Vardar suture in the Hellenides to the Inner Tauride suture along the southern border of the Kirşehir Complex in Central Anatolia. Eastwards, these belts are capped by the Oligo-Miocene Sivas Basin. Another HP/LT metamorphic belt, in the Alanya and Bitlis regions, outlines the southern flank of the Tauride Carbonate Platform. In the Alanya Nappes, south of the Taurides, eclogites and blueschists yielded metamorphic ages around 82-80 Ma (zircon U-Pb and phengite Ar-Ar data). The Alanya-Bitlis HP belt testifies an additional suture not comparable to the northerly Tavşanlı and Ören-Afyon belts, thus implying an additional oceanic branch of the Neotethys. The most likely eastern lateral continuation of this HP belt is the Bitlis Massif, in SE Turkey. There, eclogites (1.9-2.4 GPa/480-540°C) occur within calc-arenitic meta-sediments and in gneisses of the metamorphic (Barrovian-type) basement. Zircon U-Pb ages revealed 84.4-82.4 Ma for peak metamorphism. Carpholite-bearing HP/LT metasediments representing the stratigraphic cover of the Bitlis Massif underwent 0.8-1.2 GPa/340-400°C at 79-74 Ma (Ar-Ar on white mica). These conditions compares to the Tav

  16. A review of Lower and Middle Palaeozoic biostratigraphy in west peninsular Malaysia and southern Thailand in its context within the Sibumasu Terrane

    Science.gov (United States)

    Cocks, L. R. M.; Fortey, R. A.; Lee, C. P.

    2005-03-01

    Fossils from the Cambrian to Devonian rocks of southern Thailand, the Langkawi Islands, mainland Kedah, Perlis, north Perak and central West Peninsular Malaysia are listed and reviewed, and their stratigraphy and correlation reassessed. The hitherto anomalous record of the trilobite Dalmanitina from Malaysia is reviewed and found to be of latest Ordovician (Hirnantian) age, rather than Lower Silurian age as previously reported, and is considered a probable synonym of the widespread Mucronaspis mucronata. A new stratigraphical nomenclature is erected for part of the Langkawi, mainland Kedah and Perlis area successions, in which the term Setul Limestone (which stretched from the Ordovician to the Devonian) is abandoned and replaced by the Middle Ordovician Kaki Bukit Limestone, the late Ordovician and early Silurian Tanjong Dendang Formation, the Silurian Mempelam Limestone, and the early Devonian Timah Tasoh Formation, all underlying the paraconformity with the late Devonian Langgun Red Beds. There was a single depositional basin in the generally shallow-water and cratonic areas of southern Thailand, Langkawi, and mainland Kedah and Perlis, in contrast to the deeper-water basin of north Perak. Only Silurian rocks are dated with certainty within another basin in central West Malaysia, near Kuala Lumpur, which were also cratonic and shallow-water, although to the east in west Pahang there are basal Devonian deeper-water sediments with graptolites. The area is reviewed in its position within the Sibumasu Terrane, which, in the Palaeozoic, also included central and northern Thailand, Burma (Myanmar) and southwest China (part of Yunnan Province).

  17. Precambrian Cratons and Fold-Belts in Brazil: Overview

    Science.gov (United States)

    Fuck, R.

    2008-05-01

    The main Precambrian terrains recognized in Brazil comprise the Amazonian, São Francisco and Rio de la Plata cratons, surrounded by Neoproterozoic Brasiliano fold belts, making up the Borborema, Mantiqueira and Tocantins provinces. The Amazonian craton comprises an Archean core, surrounded by Paleoproterozoic terrains (Maroni-Itacaiunas, Ventuari-Tapajós, Rio Negro-Juruena), which southwestwards give way to the Mesoproterozoic Rondoniano-San Ignacio and Sunsas belts, the latter thought to be related to the Grenville belt of North America. The São Francisco craton comprises several Archean blocks (Gavião, Serrinha, Jequié) amalgamated by the Paleoproterozoic high-grade Itabuna-Salvador-Curaçá orogen. The Rio de la Plata craton, largely covered by Phanerozoic strata, is made of Paleoproterozoic basement gneiss and several Paleoproterozoic greenstone belts. Other cratonic blocks are hidden below large Phanerozoic basins, like the Paranapanema and Parnaíba blocks below the Paraná and Parnaíba basins, respectively. Several smaller Archean/Paleoproterozoic blocks appear within the Brasiliano provinces: some were strongly reworked during the Neoproterozoic orogenic events (São José do Campestre, Pernambuco-Alagoas, Goiás, Guanhães, Juiz de Fora, Curitiba), others were only marginally affected (São Luiz, Rio Apa, Luís Alves). The Brasiliano provinces are the result of Neoproterozoic to early Paleozoic orogenic events within the framework of West Gondwana amalgamation. The Mantiqueira Province extends from eastern Brazil to southern Uruguay and includes the Araçuaí, Ribeira and Dom Feliciano fold belts, bordering the São Francisco, Paranapanema and Rio de la Plata cratons and surrounding the Luís Alves craton. The Tocantins province in central Brazil includes the Araguaia, Paraguay and Brasília fold belts, the former bordering the Amazonian craton, the second bordering both the southern Amazonian craton and the Rio Apa block, and the last established on

  18. Geology and geochemistry of the Middle Proterozoic Eastern Ghat mobile belt and its comparison with the lower crust of the Southern Peninsular shield

    Science.gov (United States)

    Rao, M. V. Subba

    1988-01-01

    Two prominent rock suites constitute the lithology of the Eastern Ghat mobile belt: (1) the khondalite suite - the metapelites, and (2) the charnockite suite. Later intrusives include ultramafic sequences, anorthosites and granitic gneisses. The chief structural element in the rocks of the Eastern Ghats is a planar fabric (gneissosity), defined by the alignment of platy minerals like flattened quartz, garnet, sillimanite, graphite, etc. The parallelism between the foliation and the lithological layering is related to isoclinal folding. The major structural trend (axial plane foliation trend) observed in the belt is NE-SW. Five major tectonic events have been delineated in the belt. A boundary fault along the western margin of the Eastern Ghats, bordering the low grade terrain has been substantiated by recent gravity and the deep seismic sounding studies. Field evidence shows that the pyroxene granulites (basic granulites) post-date the khondalite suite, but are older than the charnockites as well as the granitic gneisses. Polyphase metamorphism, probably correlatable with different periods of deformation is recorded. The field relations in the Eastern Ghats point to the intense deformation of the terrain, apparently both before, during and after metamorphism.

  19. Measurement of 222Rn concentration levels in drinking water and the associated health effects in the Southern part of West bank – Palestine

    International Nuclear Information System (INIS)

    Radon concentration and annual effective doses were measured in drinking water in the Southern Part of West Bank – Palestine, by using both passive and active techniques. 184 samples were collected from various sources i.e. tap water, groundwater, rain waters and mineral waters. It is found that the annual effective dose resulting from inhalation and ingestion of radon emanated from all types of drinking water is negligible compared to the total annual effective dose from indoor radon in the region. Results reveal that there is no significant public health risk from radon ingested and inhalation with drinking water in the study region. - Highlights: • The radon concentrations are measured for drinking water samples in the southern part of West Bank – Palestine. • We conclude that there is no significant public health risk from radon ingested and inhalation with drinking water in the study region. • We recommend that this study can be used as a baseline for information or further research

  20. Investigating the spatial risk distribution of West Nile virus disease in birds and humans in southern Ontario from 2002 to 2005

    Directory of Open Access Journals (Sweden)

    Wilson Jeffrey

    2007-05-01

    Full Text Available Abstract Background The West Nile virus (WNv became a veterinary public health concern in southern Ontario in 2001 and has continued to threaten public health. Wild bird mortality has been shown to be an indicator for tracking the geographic distribution of the WNv. The purpose of this study was to investigate the latent risk distribution of WNv disease among dead birds and humans in southern Ontario and to compare the spatial risk patterns for the period 2002–2005. The relationship between the mortality fraction in birds and incidence rate in humans was also investigated. Methods Choropleth maps were created to investigate the spatial variation in bird and human WNv risk for the public health units of southern Ontario. The data were smoothed by empirical Bayesian estimation before being mapped. Isopleth risk maps for both the bird and human data were created to identify high risk areas and to investigate the potential relationship between the WNv mortality fraction in birds and incidence rates in humans. This was carried out by the geostatistical prediction method of kriging. A Poisson regression analysis was used to model regional human WNv case counts as a function of the spatial coordinates in the east and north direction and the regional bird mortality fractions. The presence of disease clustering and the location of disease clusters were investigated by the spatial scan test. Results The isopleth risk maps exhibited high risk areas that were relatively constant from year to year. There was an overlap in the bird and human high risk areas, which occurred in the central-west and south-west areas of southern Ontario. The annual WNv cause-specific mortality fractions in birds for 2002 to 2005 were 31.9, 22.0, 19.2 and 25.2 positive birds per 100 birds tested, respectively. The annual human WNv incidence rates for 2002 to 2005 were 2.21, 0.76, 0.13 and 2.10 human cases per 100,000 population, respectively. The relative risk of human WNv

  1. Use of fracture filling mineral assemblages for characterizing water-rock interactions during exhumation of an accretionary complex: An example from the Shimanto Belt, southern Kyushu Japan

    Science.gov (United States)

    Ono, Takuya; Yoshida, Hidekazu; Metcalfe, Richard

    2016-06-01

    Various fracture filling minerals and secondary minerals in fracture walls were formed by fluid-rock interaction during the exhumation of the Palaeogene Shimanto Belt of Kyushu, Japan, which is located in an accretionary complex. Each mineral formed under favourable geological conditions and can be used to estimate the conditions of accretion and formation of the related rock sequences. Petrographic observations, mineralogical and geochemical analyses were made on fracture filling minerals and secondary minerals from boreholes of ca. 140 m depth, drilled in the Shimanto Belt. Results reveal that the secondary minerals were formed in three major stages distinguished by the sequential textural relationships of the minerals and the interpreted environment of mineral formation. Filling mineral assemblages show that the studied rock formation has been subducted to a depth of several km and the temperature reached was ca. 200-300 °C. After the subduction, the rock formation was uplifted and surface acidic water penetrated up to 80 m beneath the present ground surface. The acid water dissolved calcite fracture filling minerals to form the present groundwater flow-paths, which allowed recent wall rock alteration to occur. The results shown here imply that filling mineral assemblages can be an effective tool to evaluate the environmental changes during exhumation of an accretionary complex.

  2. An Evaluation of the Wetlands and Upland Habitats and Associated Wildlife Resources in Southern Canaan Valley West Virginia

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary goal of this report is to evaluate wetland and upland habitats and associated wildlife values in the southern end of Canaan Valley. This report will...

  3. Determining Deep Basin Structure of the Hueco and southern Mesilla Bolsons, West Texas, Southern New Mexico and Northern Chihuahua Using Nonseismic Geophysical Techniques

    Science.gov (United States)

    Doser, D. I.; Avila, V.; Budhathoki, P.; Marrufo, S.; Montana, C. J.; Kaip, G.; Moncada, M.; Dena Ornelas, O.

    2012-12-01

    The Hueco and southern Mesilla bolsons are the primary groundwater source for much of the El Paso/Ciudad Juarez metropolitan region of over 1 million residents. The bolsons lie at the point where the strike of the southern Rio Grande rift changes from north-south to northwest-southeast, likely due to its interaction with pre-existing Mesozoic and Paleozoic structures. Tectonic activity continues with recent (< 750,000 years) movement along basin bounding and low level (M<4) seismicity. Over the past 4 years we have been using a conjunction of microgravity, magnetic, water well logs and electrical resistivity studies to image the complex structure of these basins within a heavily urbanized environment. These studies suggest the presence of several northwest-southeast striking cross faults within the southern Mesilla Bolson as well as an extensive subsurface andesite body related to the Cristo Rey laccolith. Intrabasin faults in the Hueco Bolson appear to cut the basin into at least 3 smaller subbasins and to control the boundary between fresh and saline water within the aquifer system beneath El Paso. We are also able to trace the East Franklins Mountain fault (last movement < 15,000 ya) at least 15 km south of the U.S.-Mexico border.

  4. Structural control and metamorphic setting of the shear zone-related Au vein mineralization of the Adola Belt (southern Ethiopia) and its tectono-genetic development

    Science.gov (United States)

    Worku, H.

    1996-10-01

    Structural study of the Adola Belt shows that most of its known and potential Au deposits occur in quartz veins which are localised within shear contacts between lithological units, and along major shear zones that divide the Adola Belt into different lithostructural domains. Analysis of the shear zone-related ore bodies and their host volcano-sedimentary succession and gneisses indicates that Au mineralization in the Adola Belt is pre-dated by two stages of deformation and a regional prograde metamorphism. The first deformation event (D 1) is a fold-and-thrust event which is characterised by low-angle thrusts, associated recumbent folds and axial planar S 1 foliation, and is related to nappe-style deformation. The second event (D 2) has folded and/or reactivated the thrust-related structures and formed upright folds and high-angle reverse shear zones and is related to the collision event. Gold mineralization occurred over a prolonged deformation history but is closely related to alteration, retrograde greenschistfacies assemblages and brittle-ductile deformation of late D 2 and D 3 transpressional shear zones that accommodate regional shortening both by crustal thickening and lateral displacement. The mineralization occurs in associated dilational jogs or bends that might have formed during the lateral or vertical expulsion. The Au-hosting shear zones are characterised by extensive development of heterogeneous mylonitic fault rocks which reveals that the accompanied deformation is characterised by processes that can increase the porosity and permeability of the rocks within the shear zones. This gave rise to further extensive dilatancy within the major dilational jogs and produced a suitable structural regime for vein-hosted Au mineralization. This implies that the Au mineralization is epigenetic in origin and that it resulted from precipitation from metamorphic hydrothermal fluids circulating through major shear zones and associated structures late during the

  5. The Grenvillian Namaqua-Natal fold belt adjacent to the Kaapvaal Craton: 1. Distribution of Mesoproterozoic collisional terranes deduced from results of regional surveys and selected profiles in the western and southern parts of the fold belt

    Science.gov (United States)

    Colliston, W. P.; Schoch, A. E.; Cole, J.

    2014-12-01

    Sixteen tectonic terranes of the Namaqua-Natal metamorphic complex are distinguished (the Aggeneys, Agulhas, Bladgrond, Gamka, Grootdrink, Grünau, Fraserburg, Upington, Margate, Mossel, Mzumbe, Okiep, Olifantshoek, Steinkopf, Pofadder, and Tugela terranes). Evidence obtained from field investigations in the outcrop regions of Namaqualand and Natal are correlated with the geophysical data, enabling recognition of terrane suboutcrops in the regions covered by Phanerozoic deposits in the south. This is illustrated by nine selected profiles over the western and southern parts of the metamorphic complex. Four terranes that have not been observed in outcrop are postulated (Agulhas, Fraserburg, Gamka and Mossel terranes) and may represent extensions of some of the Natal terranes (Mzumbe and Margate terranes). The depth to Moho is generally about 40 km, diminishing dramatically at the present continental edge to as little as 15 km. Listric thrust ramps may originate on rises of the gently undulating topography of the Moho zone. Zones of thrusting and later shearing often exploit older structures and fabrics. The terranes that participated in the Grenvillian Namaqua-Natal Orogeny exhibit a dichotomy of vergences regionally. Those that moved to the northeast and north accreted onto the Archaean Kaapvaal Craton before becoming part of the Kalahari Craton. Terranes with vergences to the south and southwest were amalgamated onto other Archaean cratons. All of the composite cratons took part in the assembly of Rodinia.

  6. Triple junction orogeny: tectonic evolution of the Pan-African Northern Damara Belt, Namibia

    Science.gov (United States)

    Lehmann, Jérémie; Saalmann, Kerstin; Naydenov, Kalin V.; Milani, Lorenzo; Charlesworth, Eugene G.; Kinnaird, Judith A.; Frei, Dirk; Kramers, Jan D.; Zwingmann, Horst

    2014-05-01

    Trench-trench-trench triple junctions are generally geometrically and kinematically unstable and therefore can result at the latest stages in complicated collisional orogenic belts. In such geodynamic sites, mechanism and timescale of deformations that accommodate convergence and final assembly of the three colliding continental plates are poorly studied. In western Namibia, Pan-African convergence of three cratonic blocks led to pene-contemporaneous closure of two highly oblique oceanic domains and formation of the triple junction Damara Orogen where the NE-striking Damara Belt abuts to the west against the NNW-striking Kaoko-Gariep Belt. Detailed description of structures and microstructures associated with remote sensing analysis, and dating of individual deformation events by means of K-Ar, Ar-Ar (micas) and U-Pb (zircon) isotopic studies from the Northern Damara Belt provide robust constraints on the tectonic evolution of this palaeo-triple junction orogeny. There, passive margin sequences of the Neoproterozoic ocean were polydeformed and polymetamorphosed to the biotite zone of the greenschist facies to up to granulite facies and anatexis towards the southern migmatitic core of the Central Damara Belt. Subtle relict structures and fold pattern analyses reveal the existence of an early D1 N-S shortening event, tentatively dated between ~635 Ma and ~580 Ma using published data. D1 structures were almost obliterated by pervasive and major D2 E-W coaxial shortening, related to the closure of the Kaoko-Gariep oceanic domain and subsequent formation of the NNW-striking Kaoko-Gariep Belt to the west of the study area. Early, km-scale D1 E-W trending steep folds were refolded during this D2 event, producing either Type I or Type II fold interference patterns visible from space. The D2 E-W convergence could have lasted until ~533 Ma based on published and new U-Pb ages. The final D3 NW-SE convergence in the northernmost Damara Belt produced a NE-striking deformation

  7. Role of phosphate solubilizing Burkholderia spp. for successful colonization and growth promotion of Lycopodium cernuum L. (Lycopodiaceae) in lateritic belt of Birbhum district of West Bengal, India.

    Science.gov (United States)

    Ghosh, Ranjan; Barman, Soma; Mukherjee, Rajib; Mandal, Narayan C

    2016-02-01

    Profuse growth of Lycpodium cernuum L. was found in phosphate deficient red lateritic soil of West Bengal, India. Interaction of vesicular-arbuscular mycorrhiza (VAM) with Lycopodium rhizoids were described earlier but association of PGPR with their rhizoids were not studied. Three potent phosphate solubilizing bacterial strains (P4, P9 and P10) associated with L. cernuum rhizoids were isolated and identified by 16S rDNA homologies on Ez-Taxon database as Burkholderia tropica, Burkholderia unamae and Burkholderia cepacia respectively. Day wise kinetics of phosphate solubilization against Ca3(PO4)2 suggested P4 (580.56±13.38μgml(-1)) as maximum mineral phosphate solubilizer followed by P9 (517.12±17.15μgml(-1)) and P10 (485.18±14.23μgml(-1)) at 28°C. Release of bound phosphates by isolated strains from ferric phosphate (FePO4), aluminum phosphate (AlPO4) and four different complex rock phosphates indicated their very good phosphate solubilizng efficacy. Nitrogen independent solubilizition also supports their nitrogen fixing capabilities. Inhibition of P solubilization by calcium salts and induction by EDTA suggested pH dependent chelation of metal cations by all of the isolates. Rhizoidal colonization potentials of Burkholderia spp. were confirmed by in planta experiment and also using scanning electron microscope (SEM). Increases of total phosphate content in Lycopodium plants upon soil treatment with these isolates were also recorded. In addition siderophore production on CAS agar medium, tryptophan dependent IAA production and antifungal activities against pathogenic fungi by rhizospheric isolates deep-rooted that they have definite role in nutrient mobilization for successful colonization of L. cernuum in nutrient deficient lateritic soil. PMID:26805621

  8. Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations

    Science.gov (United States)

    Hudson, Mark R.; John, David A.; Conrad, James E.; McKee, Edwin H.

    2000-01-01

    Paleomagnetic and geochronologic data combined with geologic mapping tightly restrict the timing and character of a late Oligocene to early Miocene episode of large magnitude extension in the southern Stillwater Range and adjacent regions of west central Nevada. The southern Stillwater Range was the site of an Oligocene to early Miocene volcanic center comprising (1) 28.3 to 24.3 Ma intracaldera ash flow tuffs, lava flows, and subjacent plutons associated with three calderas, (2) 24.8 to 20.7 Ma postcaldera silicic dikes and domes, and (3) unconformably overlying 15.3 to 13.0 Ma dacite to basalt lava flows, plugs, and dikes. The caldera-related tuffs, lava flows, and plutons were tilted 60°-70° either west or east during the initial period of Cenozoic deformation that accommodated over 100% extension. Directions of remanent magnetization obtained from these extrusive and intrusive, caldera-related rocks are strongly deflected from an expected Miocene direction in senses appropriate for their tilt. A mean direction for these rocks after tilt correction, however, suggests that they were also affected by a moderate (33.4° ± 11.8°) component of counterclockwise vertical axis rotation. Paleomagnetic data indicate that the episode of large tilting occurred during emplacement of 24.8 to 20.7 Ma postcaldera dikes and domes. In detail, an apparent decrease in rotation with decreasing age of individual, isotopically dated bodies of the postcaldera group indicates that most tilting occurred between 24.4 and 24.2 Ma. The onset of tilting immediately following after the final caldera eruptions suggests that the magmatism and deformation were linked. Deformation was not driven by magma buoyancy, however, because tilting equally affected the caldera systems of different ages, including their plutonic roots. It is more likely that regional extension was focused in the southern Stillwater Range due to magmatic warming and reduction of tensile strength of the brittle crust

  9. 39Ar/40Ar dating of the trans-Himalayan calc-alkaline magmatism of southern Tibet

    International Nuclear Information System (INIS)

    The results are reported of an 39Ar-40Ar age determination investigation which show that the earlier basic plutons of the southern edge of the trans-Himalayan belt have ages of 90-110 Myr (Albian to Cenomanian), whereas the lavas of the upper unconformable series are clearly younger (60 Myr, Palaeocene). Comparing the present results with those obtained from the Ladakh and Kohistan magmatic belts further west it is concluded that a subduction zone has been active during the Cretaceous between India and Asia. (U.K.)

  10. Reconstruction and Comparison of P-T Paths in the Andrelândia Nappe System, Southern Brasília Fold Belt, MG

    OpenAIRE

    Rafael Gonçalves da Motta; Renato de Moraes; Rudolph Allard Johannes Trouw; Mário da Costa Campos Neto

    2010-01-01

    The Andrelândia Nappe System consists of three main nappes, from bottom to top: the lower Andrelândia nappe, themiddle Liberdade nappe and the upper Três Pontas-Varginha nappe and associated klippen, Pouso Alto, Aiuruoca, Carvalhosand Serra da Natureza. In the Andrelândia Nappe System, metamorphism increases from north to south and east to west, withthe highest temperatures and pressures recorded in rocks of the Três Pontas-Varginha nappe and associated klippen. Samplesof pelitic and mafic ro...

  11. Regional structure of the southern segment of Central Iberian Zone (Spanish Variscan Belt) interpreted from potential field images and 2.5 D modelling of Alcudia gravity transect

    Science.gov (United States)

    García-Lobón, J. L.; Rey-Moral, C.; Ayala, C.; Martín-Parra, L. M.; Matas, J.; Reguera, M. I.

    2014-02-01

    This study presents a structural interpretation of potential field data at the southern segment of the Spanish Central Iberian Zone, where little is known about its geometry and physical properties in depth. We used ground gravity and aeromagnetic data from the Spanish Geological Survey (IGME) databases, together with a gravity survey recently acquired along the Alcudia deep seismic reflection profile, and also petrophysical data from rock samples, in part specifically acquired for this work. The aim is to characterize with potential fields the depth structure and physical properties of a complex area, focusing on features of the upper crust where the potential fields can provide a useful insight, as these features appear to be transparent in the images of seismic surveys carried up to date. After building a 2.5 D model of the magnetic susceptibility and density distribution for the whole crust with the constraints of the Alcudia seismic transect, relationships between lower and upper crustal structures can be better established, and surface geophysical maps allow estimating the lateral extensions of the main structures characterized by the potential field modelling. Interpreted gravity and magnetic Alcudia features consist of: 1) long-wavelength anomalies due to changes in crustal thickness and structure, identified along the Alcudia seismic reflection profile; some crustal boundaries and the seismic Moho have been slightly modified in the potential field model to fit the observed data; and, 2) short wavelength anomalies related to upper crustal features as large NW-SE faults and folds, and plutonic alignments. Northern and southern Alcudia segments show relevant lower-middle crust shortening structures underneath extensive Variscan plutons (Mora, Pedroches) and folded basins (Pedroches). Potential field imaging and modelling of these structures have provided a better understanding of the subsurface geology, particularly in non-reflective areas, unravelling the

  12. The 2010-2011 Revival of Jupiter's South Equatorial Belt: Perturbations of Temperatures, Clouds and Composition from Infrared Observations

    Science.gov (United States)

    Orton, G.; Fletcher, L.; Yanamandra-Fisher, P.; Sanchez-Lavega, A.; Perez-Hoyos, S.; Baines, K.; de Pater, I.; Wong, M.; Goetz, R.; Valkov, S.; Greco, J.; Edwards, M.; Rogers, J.

    2011-01-01

    On 2010 November 9, a perturbation appeared in Jupiter's South Equatorial Belt (SEB), which began a classical "revival" of the SEB, returning the entire axisymmetric region to its normal dark color from its anomalous, light, "faded" state. The early revival is marked by strong upwelling gas at the outbreak location, to the west of which appear alternating clear and cloudy regions. Clear regions are correlated with dark clouds near the outbreak and in a southern retrograding branch but less so in a northern prograding branch. A 5-micrometer image from 2010 March 1 shows much of the SEB closer to a pre-faded state.

  13. Adakitic magmatism in post-collisional setting: An example from the Early-Middle Eocene Magmatic Belt in Southern Bulgaria and Northern Greece

    Science.gov (United States)

    Marchev, Peter; Georgiev, Stoyan; Raicheva, Raya; Peytcheva, Irena; von Quadt, Albrecht; Ovtcharova, Maria; Bonev, Nikolay

    2013-11-01

    Post-collisional (56.0-40.4 Ma) adakitic magmatism in the Rhodope Massif and the Kraishte region, including W. Srednogorie, in South Bulgaria followed the collision of the Rhodope and Pelagonian Massifs. It forms a 250 km NW trending belt which continues into the 1000 km long belt of Eocene magmatism in northern Turkey and Iran. The rocks are represented by felsic subvolcanic dykes and sills in the Kraishte and plutons in the Rhodopes. Here, we synthesize new chemical (whole-rock major and trace elements, and Sr and Nd isotopes) and LA-ICP/MS mineral and U-Pb zircon age data along with published similar data in order to constrain the genesis of this magmatism and the early Cenozoic geodynamic evolution of the central Balkan Peninsula. The rocks display typical subduction-related characteristics with enrichment in LILE and LREE and depletion in HFSE (Nb, Ta and Ti). In the Kraishte and western Srednogorie Zones these are calc-alkaline to high-K calc-alkaline rhyolites, displaying a typical adakitic signature, i.e. high La/Yb and Sr/Y ratios. The studied Rhodope Massif rocks are predominantly high-K calc-alkaline and subordinate calc-alkaline granites and granodiorites with a minor amount of tonalites. Petrographically, they are H2O- and accessory-rich (allanite, epidote, titanite, apatite) rocks, showing geochemical affinities from non-adakitic tonalites and mafic granodiorites to adakitic granodiorites and granites. Similarity of Sr and Nd isotopic compositions of the Kraishte subvolcanic and Rhodope intrusive adakitic rocks with the neighboring and coeval NW Anatolian basaltic to dacitic volcanics and plutons suggests that the most likely source for the South Bulgarian adakitic rocks is the subduction-enriched depleted lithospheric mantle. The nearby and contemporaneous East Serbian alkaline basalts are isotopically and compositionally different and, probably, originate from an OIB-like mantle source. Subsequent fractionation within an isotopically similar lower

  14. Belt attachment and system

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Abraham D.; Davidson, Erick M.

    2016-02-02

    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  15. The 29 July 2014 (Mw 6.4) Southern Veracruz, Mexico Earthquake: Scenary Previous to Its Occurrence.

    Science.gov (United States)

    Yamamoto, J.

    2014-12-01

    On 29 July 2014 (10:46 UTC) a magnitude 6.4 (Mw) earthquake occurred at the southern Veracruz, Mexico region. The epicenter was preliminary located at 17.70° N and 95.63° W. It was a normal fault event with the slip on a fault that trend NNW and a focus approximately 117 km below the surface of the Gulf of Mexico costal plane. The earthquake was widely felt through centro and southern Mexico. In Oaxaca City 133 km to the south a person die of a hearth attack. No damages were reported. Most prominent moderate-sized earthquakes occurring in the southern Veracruz region since 1959 has been concentrated along two well defined seismic belts. One belt runs off the coast following nearly its contour. Here the earthquakes are shallow depth and mostly show a reverse fault mechanism. This belt of seismicity begins at the Los Tuxtlas volcanic field. Another seismic belt is located inland 70 km to the west. Here most earthquakes are of intermediate-depth (108-154 km) focus and normal faulting mechanism. The July 2014 earthquake is located near to this second seismic belt. In the present paper we discuss, within the regional geotectonic framework, the location and some aspects of the rupture process of the July 2014 earthquake.

  16. 南方国家终端市场:“一带一路”战略的新机遇%The End Markets in Southern Countries:New Opportunities for "One Belt, One Road" Strategy

    Institute of Scientific and Technical Information of China (English)

    沈梓鑫; 贾根良

    2015-01-01

    The research shows that Chinese enterprises are impossible to gradually upgrade to the high end of global value chain which is dominated by multinational corporations from developed countries and become their replacers through integrating into the chain. It is an inevitable fate for them to be locked in the low and middle end of value chain for a long time, which is the predicament that China cannot escape. The historical experiences of developed countries succeeded are worth of learning and references, those countries once were less-developed in history all achieved the rising by refusing to be integrated into the leading economies at that time and establishing the commodity chain controlled by themselves in the backward countries. The core of "one belt, one road" strategy is that the focus of economic globalization for China should be changed to the southern nations. After the outbreak of global financial crisis, the end markets of global export shift from the North to the South at a much quicker pace, such significant changes in world economic pattern provide new opportunities for the "one belt, one road" strategy to get success on the basis of historical experiences. The transferring of end markets to southern nations provide specific ways of implement "one belt, one road" strategy, and the purpose of this strategy is not to tackle the problems of overcapacity, but to establish a new ecosystem of global value chain controlled by Chinese enterprises so that China can realize the strategic objective of transformation and upgrading.%研究说明,中国企业不可能通过融入发达国家跨国公司控制的全球价值链逐步升级到高端并成为其替代者,长期锁定在价值链的中低端是必然的宿命,这是我国目前转型升级难以摆脱的困局。发达国家成功的历史经验值得借鉴,当他们在历史上处于欠发达状态时都是通过拒绝与当时领先经济一体化并在落后国家建立自身掌控的商品

  17. Segmentations of foreland belts and their tectonic mechanism in the Southwest Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    QU Guosheng; LI Yigang; LI Yanfeng; J. Canerot; CHEN Xinfa; YIN Junping; CHEN Xinan; ZHANG Ning; J. Deramond

    2005-01-01

    Based on lots of field investigations and comprehensive interpretations of seismic profiles with outcrop cross-sections, this paper shows that the foreland belts surrounding the Southwest Tarim Foreland Basin have the regularity of segmentation along the strike of foreland belts. There are many thin-skinned thrusting systems thrusting from mountains to the basin and the arcuate back-thrusting systems to the mountains distributed at intervals in the front of West Kunlun-Pamir and Southern Tianshan. Between thrusting and back-thrusting systems, the strike-slip faults developed. The northeast uplifts and depressions of Southwest Tarim Basin correspond with the segmentation of foreland basin. The thin-skinned thrusting system is formed in the case that the thickness of sedimentary covers is less than 10 km in depth where the basement is an uplift belt in general. The back-thrusting systems and triangle zones are formed in the case that the thickness of sedimentary covers is larger than 8 km in depth where the basement is a depression zone. The main mechanics of segmentation of foreland basin are the difference of mountain uplift and deformation rate along the longitude of the mountains, the huge sedimentary rocks in different depression centers, the uplift belts and depression zones in the basement rocks, and multi-displaced weak layers in the foreland basin. The segmentation of Southwest Tarim Foreland Basin is due to the intra-plate deformation of re-orogenies of West Kunlun-Pamir and Southwest Tianshan and the co-related deformation between mountains and basement of basin since Neocene.

  18. Metal partitioning in sediments and mineralogical controls on the acid mine drainage in Ribeira da Água Forte (Aljustrel, Iberian Pyrite Belt, Southern Portugal)

    International Nuclear Information System (INIS)

    This work focuses on the geochemical processes taking place in the acid drainage in the Ribeira da Água Forte, located in the Aljustrel mining area in the Iberian Pyrite Belt. The approach involved water and stream sediment geochemical analyses, as well as other techniques such as sequential extraction, Mössbauer spectroscopy, and X-ray diffraction. Ribeira da Água Forte is a stream that drains the area of the old mine dumps of the Aljustrel mine, which have for decades been a source of acid waters. This stream flows to the north for a little over than 10 km, but mixes with a reduced, organic-rich, high pH waste water from the municipal waste water pools of the village. This water input produces two different results in the chemistry of the stream depending upon the season: (i) in the winter season, effective water mixing takes place, and the flux of acid water from the mine dumps is continuous, resulting in the immediate precipitation of the Fe from the acid waters; (ii) during the summer season, acid drainage is interrupted and only the waste water feeds the stream, resulting in the reductive dissolution of Fe hydroxides and hydroxysulfates in the stream sediments, releasing significant quantities of metals into solution. Throughout the year, water pH stays invariably within 4.0–4.5 for several meters downstream of this mixing zone even when the source waters come from the waste water pools, which have a pH around 8.4. The coupled interplay of dissolution and precipitation of the secondary minerals (hydroxides and sulfates), keeps the system pH between 3.9 and 4.5 all along the stream. In particular, evidence suggests that schwertmannite may be precipitating and later decomposing into Fe hydroxides to sustain the stream water pH at those levels. While Fe content decreases by 50% from solution, the most important trace metals are only slightly attenuated before the solution mixes with the Ribeira do Rôxo stream waters. Concentrations of As are the only ones

  19. Conceptual model about the interaction between El Nio/ Southern Oscillation and Quasi-Biennial Oscillation in far west equatorial Pacific

    Institute of Scientific and Technical Information of China (English)

    LIU; Qinyu

    2006-01-01

    [1]White W B,Cayan D R.A global El Nino-Southern Oscillation wave in surface temperature and pressure and its interdecadal modulation from 1900 to 1996.J Geophys Res,2000,105 C5:11223-11242[2]White W B,Allan R J.A global quasi-biennial wave in surface temperature and pressure and its decadal modulation from 1900 to 1994.J Geophys Res,2001,106 C11:26789-26803[3]Jin F F,Neelin D,Ghil M.El Nino on the Devil's staircase:Annual subharmonic steps to chaos.Science,1994,264:70-72[4]Tziperman E,Stone L,Cane M,et al.El Nino chaos:Overlapping of resonances between the seasonal and the Pacific ocean-atmos-phere oscillator.Science,1994,264:72-74[5]Flügel M,Chang P.Stochastically induced climate shift of El Nino-Southern Oscillation.Geophys Res Lett,1999,26(16):2473-2477[6]Clarke A J,Liu X,Gorder S V.Dynamic of the biennial oscillation in the equatorial Indian and far western Pacific Oceans.J Clim,1998,11:987-1001[7]Lau K M,Wu H T.Assessment of the impacts of the 1997-98 El Nino on the Asian-Australia Monsoon.Geophys Res Lett,1999,26(12):1747-1750[8]Chang C P,Li T.A theory for the tropospheric biennial oscillation.J Atmos Sci,2000,57:2209-2224[9]Wang B,Wu R,Fu X.Pacific-East Asian teleconnection:How does ENSO affect East Asian climate? J Clim,2000,13:1517-1536[10]Li C,Hu J.A analysis of interaction between the atmospheric circulation over East Asia/Northwest Pacific and El Nino.Chin J Atmos Sci,1987,11:411-420[11]Liu Z.A simple model study of ENSO suppression by external periodic forcing.J Clim,2002,15:1088-1098[12]Pan A,Liu Q,Liu Z.Periodic forcing and ENSO supression in the Cane-Zibiak Model J Oceanogr,2005,61(1):109-113[13]Weisberg R H,Wang C.A Western Pacific oscillator paradigm for the El Nino-Southern Oscillation.Geophys Res Lett,1997,24:779-782[14]Wang B,Wu R,Lukas R.Roles of the western North Pacific wind variation in thermocline adjustment and ENSO phase transition.J Meteor Soc Japan,1999,77:1-16[15]Wang C,Weisberg R H,Virmani J I.Western Pacific interannual

  20. Radiological survey and assessment of associated activity concentration of the naturally occurring radioactive materials (NORM) in the Migori artisanal gold mining belt of southern Nyanza, Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Odumo, O.B., E-mail: benodumoo@uonbi.ac.k [Department of Physics, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya); Mustapha, A.O. [Department of Physics, University of Agriculture, P.M.B. 2240 Abeokuta (Nigeria); Patel, J.P.; Angeyo, H.K. [Department of Physics, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya)

    2011-06-15

    A radiological survey and assessment was carried out at selected sites (Osiri, Mikei, Masara and Macalder) in the Migori gold mines of southern Nyanza, Kenya to determine the levels of exposure of the artisanal miners to the naturally occurring radioactive materials (NORM) and dust. The activity concentrations of {sup 40}K and the decay products of {sup 232}Th and {sup 226}Ra were obtained using an innovative method in single channel NaI(Tl) gamma-ray spectrometry. The counts for both the sample and the reference material in a specific window for a particular radionuclide were compared to arrive at the activity concentration of the radionuclide in the sample. Measurement of dust loading at various crushing sites was carried out by trapping the dust particles on a 0.45 {mu}m cellulose acetate filter paper (47 mm diameter) using a vacuum pump. The activity concentration levels range widely 80-413, 12-145 and 21-258 Bq/kg for {sup 40}K, {sup 232}Th and {sup 226}Ra, respectively. The calculated absorbed dose in air range from 16 to 178 nGy/h (with a mean of 42 nGy/h). Dust loading was found to range from 1.3 to 3.7 mg/m{sup 3}. Although the activity concentration of the radionuclides and the calculated annual absorbed dose is below the world's average, the dust level at the mines was relatively high. The results obtained show that the artisanal miners are exposed to various levels of radionuclides and dust and necessary precautions need to be taken.

  1. Southern montane populations did not contribute to the recolonization of West Siberian Plain by Siberian larch (Larix sibirica): a range-wide analysis of cytoplasmic markers.

    Science.gov (United States)

    Semerikov, Vladimir L; Semerikova, Svetlana A; Polezhaeva, Maria A; Kosintsev, Pavel A; Lascoux, Martin

    2013-10-01

    While many species were confined to southern latitudes during the last glaciations, there has lately been mounting evidence that some of the most cold-tolerant species were actually able to survive close to the ice sheets. The contribution of these higher latitude outposts to the main recolonization thrust remains, however, untested. In the present study, we use the first range-wide survey of genetic diversity at cytoplasmic markers in Siberian larch (Larix sibirica; four mitochondrial (mt) DNA loci and five chloroplast (cp) DNA SSR loci) to (i) assess the relative contributions of southern and central areas to the current L. sibirica distribution range; and (ii) date the last major population expansion in both L. sibirica and adjacent Larix species. The geographic distribution of cpDNA variation was uninformative, but that of mitotypes clearly indicates that the southernmost populations, located in Mongolia and the Tien-Shan and Sayan Mountain ranges, had a very limited contribution to the current populations of the central and northern parts of the range. It also suggests that the contribution of the high latitude cryptic refugia was geographically limited and that most of the current West Siberian Plain larch populations likely originated in the foothills of the Sayan Mountains. Interestingly, the main population expansion detected through Approximate Bayesian Computation (ABC) in all four larch species investigated here pre-dates the LGM, with a mode in a range of 220,000-1,340,000 years BP. Hence, L. sibirica, like other major conifer species of the boreal forest, was strongly affected by climatic events pre-dating the Last Glacial Maximum. PMID:24033458

  2. Geochemical evolution of groundwater in southern Bengal Basin: The example of Rajarhat and adjoining areas, West Bengal, India

    Indian Academy of Sciences (India)

    Paulami Sahu; P K Sikdar; Surajit Chakraborty

    2016-02-01

    Detailed geochemical analysis of groundwater beneath 1223 km2 area in southern Bengal Basin along with statistical analysis on the chemical data was attempted, to develop a better understanding of the geochemical processes that control the groundwater evolution in the deltaic aquifer of the region. Groundwater is categorized into three types: `excellent', `good' and `poor' and seven hydrochemical facies are assigned to three broad types: `fresh', `mixed' and `brackish' waters. The `fresh' water type dominated with sodium indicates active flushing of the aquifer, whereas chloride-rich `brackish' groundwater represents freshening of modified connate water. The `mixed' type groundwater has possibly evolved due to hydraulic mixing of `fresh' and `brackish' waters. Enrichment of major ions in groundwater is due to weathering of feldspathic and ferro-magnesian minerals by percolating water. The groundwater of Rajarhat New Town (RNT) and adjacent areas in the north and southeast is contaminated with arsenic. Current-pumping may induce more arsenic to flow into the aquifers of RNT and Kolkata cities. Future large-scale pumping of groundwater beneath RNT can modify the hydrological system, which may transport arsenic and low quality water from adjacent aquifers to presently unpolluted aquifer.

  3. Mosquito fauna and perspectives for integrated control of urban vector-mosquito populations in Southern Benin (West Africa).

    Science.gov (United States)

    Lingenfelser, Andre; Rydzanicz, Katarzyna; Kaiser, Achim; Becker, Norbert

    2010-01-01

    This study aims at an integrated vector management (IVM) concept of implementing biological control agents against vector mosquito larvae as a cost-effective and scalable control strategy. In the first step, the mosquito species composition fauna of southern Benin was studied using standard entomological procedures in natural and man-made habitats. Altogether, 24 species belonging to 6 genera of mosquitoes Aedes, Anopheles, Culex, Mansonia, Uranotaenia, Ficalbia were recorded. Five species, Cx. thalassius, Cx. nebulosus, Cx. perfuscus, Cx. pocilipes and Fi. mediolineata are described the first time for Benin. The local mosquito species showed high susceptibility to a Bacillus sphaericus formulation (VectoLex(R) WDG ) in a standardized field test. A dosage of 1 g/m(2) was effective to achieve 100 percent mortality rate for Cx. quinquefasciatus late instar larvae in a sewage habitat, with a residual effect of up to 7 days. After more than 1 year of baseline data collection, operational larviciding with B. thuringiensis var. israelensis and B. sphaericus was commenced in 2006 in selected areas. Microbial insecticides products for larval control show great potential within IVM programmes and may augment control efforts against adult insects, such as the use of insecticide-treated bed nets or indoor wall spraying in many parts of Africa. PMID:20684480

  4. SHRIMP U-Pb age and high temperature conditions of the collisional metamorphism in the Várzea do Capivarita Complex: Implications for the origin of Pelotas Batholith, Dom Feliciano Belt, southern Brazil

    Science.gov (United States)

    Philipp, Ruy Paulo; Bom, Francisco Molina; Pimentel, Márcio Martins; Junges, Sérgio Luiz; Zvirtes, Gustavo

    2016-03-01

    The Várzea do Capivarita Complex is composed of pelitic gneisses with subordinate calc-silicate rock, marble and rare quartzite. It is part of the neoproterozoic Dom Feliciano Belt, in southern Brazil. The gneisses are associated to veins and tabular leucogranite bodies, which are the product of anatexis of the pelitic gneiss. The paragneisses of the Várzea do Capivarita Complex are tectonically juxtaposed to orthogneisses of the Arroio dos Ratos Complex. This complex is exposed as megaxenoliths in granites of the Encruzilhada do Sul Suite and as smaller fragments in the Quitéria and Cordilheira Granites, all part of the Pelotas Batholith. The metamorphic foliation is oriented to N30°W, with dips between 35 and 55° to the SW and mineral lineation is suborizontal with rake ranging from 15° to 30° and down dip to NW and SE, suggesting deformation associated with a transpressive system. Based on the paragenesis garnet-cordierite-sillimanite-biotite, metamorphism occurred at 720-820° C and pressure of 8-9 kbar, characterizing it as of intermediate pressure and high temperature series. Zircon grains of one sample of garnet-cordierite-sillimanite-biotite gneiss and one of peraluminous leucogranite was dated by the U-Pb SHRIMP method. The paragneiss metamorphic zircon yielded an age of 619 ± 4.3 Ma interpreted as an age of the main metamorphic event, whereas igneous zircon grains from the leucogranite indicates that magma crystallization took place at 620 ± 6.3 Ma. The main metamorphic foliation (S2) of the paragneiss and the leucogranite magmatic foliation (S0) are parallel to each other, indicating that they were formed during the same event. This suggests that anatexis of the paragneisses of the Várzea do Capivarite Complex generated the peraluminous leucogranites right after the climax of the collisional metamorphism.

  5. Selenium distribution and mode of occurrence in the Kanawha Formation, southern West Virginia, U.S.A.

    Energy Technology Data Exchange (ETDEWEB)

    Vesper, Dorothy J.; Rhoads, Christina J. [West Virginia University, Department of Geology and Geography, PO Box 6300, Morgantown, WV 26506 (United States); Roy, Mimi [West Virginia University, Department of Plant and Soil Sciences, PO Box 6108, Morgantown, WV 26506 (United States)

    2008-02-01

    Selenium concentrations were measured in five rock cores from a mine in Boone County, West Virginia to determine their relationship to sulfur, rock type and stratigraphic location. The samples spanned the Winifrede and Coalburg coal beds of the Middle Pennsylvania upper Kanawha Formation and included coals and clastic lithologies. The coals generally contained the highest concentrations of Se and the sandstones the lowest. No correlation was observed between total Se and sulfur concentrations for either the entire data set or for individual lithologies. Better correlations were identified for log concentrations between total Se and total organic carbon. Principal component analysis identified a strong sulfur-acid component, interpreted to be due to sulfide mineral presence, which correlates well with S but not with Se. Coal sample chemistry is more likely to load onto this component while clastic rock chemistry is more likely to load onto the second, non-sulfur component. Se concentrations load onto both components indicating they are not controlled by a single overriding chemistry. Selective extractions indicate that Se is distributed between both sulfide and organically-bound fractions, as defined by the test. Overall, the lack of correlation between Se and S, the distribution of Se among extracted fractions, and the loading of Se onto both sulfur and non-sulfur components support that the Se in these rock layers is distributed in more than one chemically-bound form. Non-coal rock units with the highest concentrations of Se were found adjacent to coal beds, suggesting that redistribution of Se may have occurred post-deposition. The acidic domed swamps that formed these coals were low in sulfur and a reasonable chemical setting to accumulate Se if it were introduced. The preservation of Se in the domed swamp peat coupled with post-depositional redistribution may partly explain the data presented. (author)

  6. Early Silurian (~ 440 Ma) adakitic, andesitic and Nb-enriched basaltic lavas in the southern Altay Range, Northern Xinjiang (western China): Slab melting and implications for crustal growth in the Central Asian Orogenic Belt

    Science.gov (United States)

    Shen, Xiao-Ming; Zhang, Hai-Xiang; Wang, Qiang; Ma, Lin; Yang, Yue-Heng

    2014-10-01

    As an important part of the Central Asian Orogenic Belt (CAOB), the Altay Range contains large-scale Paleozoic magmatic rocks. However, owing to the lack of precise age constraints, the tectonic setting and petrogenesis of the magmatic rocks in this area have been controversial, which has led to the debate on Phanerozoic crustal growth mechanisms and accretionary orogenic processes in the CAOB. Herein, we report geochronological and geochemical data of the Suoerkuduke adakitic, andesitic and Nb-enriched basaltic (NEB) lavas in the southern margin of the southern Altay Range. LA-ICP-MS zircon U-Pb analyses for five adakitic, andesitic and NEB samples indicate that they were coevally generated in the Early Silurian (~ 440 Ma). The adakites and basaltic andesites are geochemically characterized by high Na2O/K2O, Sr/Y, Al2O3, Sr, εNd(t) and zircon εHf(t) values and relatively low (87Sr/86Sr)i ratios. The NEBs are sodium-rich and have higher TiO2, P2O5, Zr, Nb, and Nb/U values than those of typical arc basalts. They also have positive εNd(t) values and positive and variable zircon εHf(t) values. We suggest that the Suoerkuduke adakites were derived by a partial melting of the subducted oceanic crust with minor overlying sediments, and the continuous compositional variations between adakites and basaltic andesites confirm that the interaction between slab melts and mantle peridotite played an important role in the formation of basaltic andesites. The associated NEBs were possibly generated by a partial melting of mantle wedge peridotites metasomatized by slab-derived adakitic melts and minor fluids. In combination with the occurrence of voluminous Silurian-Devonian granitoids, coeval ophiolite mélanges, and a series of intra-arc basins, a slab window model triggered by slab tearing is proposed to account for the formation of the Suoerkuduke adakite-basaltic andesite-NEB suites. The upwelling of the asthenospheric mantle through the slab window probably caused

  7. Genesis and Characteristics of the Two Sub-belts in the Western Yarlung-Zangbo Suture Zone, Tibet, China

    Science.gov (United States)

    Liu, F.; Yang, J.; Lian, D.; Dilek, Y.; Robinson, P. T.

    2014-12-01

    The Yarlung Zangbo Suture zone (YZSZ), extending more than 2000 km across southern Tibet, is thought to mark the tectonic boundary between the Indian and Asian plates. West of Saga county of the YZSZ is divided into two sub-belts (Dajiweng-Saga to the north and Daba-Xiugugabu to the south), which are separated by the Zhongba-Zhada microcontinent/terrane containing Sinian to Triassic metamorphic and sedimentary rocks. Several large ophiolitic massifs that crop out in the southern sub-belt, e.g., the Dongbo (400 km2), Purang (650km2) and Xiugugabu (700km2), have a seamount-like stratigraphy, consisting from the base upward of peridotites, mafic dikes, massive basalt and basaltic hyaloclastites, mudstone and silty shale and radiolarian chert. The sedimentary sequence also locally contains discontinuous basalt flows and siliceous to massive limestones with minor oolites. The peridotites are highly depleted harzburgites, minor lherzolites and dunites, all of which were enriched by later fluids/melts. Mafic dikes (120-130 Ma) intruding the peridotites exhibit N-MORB-like chondrite-normalized REE patterns and negative Nb anomalies in spider diagrams. These geochemical features are similar to those of volcanic-rifted margin basalts. E-MORB-like basalts (137 Ma) within the Late Jurassic to Early Cretaceous radiolarian cherts and OIB-like basalts (140 Ma) between the silty shale and peridotites reflect limited seamount volcanism. In the northern sub-belt ophiolitic peridotites, mafic dikes, cumulate gabbros, massive basalts, chert and limestone crop out discontinuously as lenses in mélange complexes. The peridotites are harzburgite and minor dunite, both of which were modified by later LREE-enriched melts/fluids. Mafic dikes (122-127 Ma) intruding the peridotites are geochemically similar to those in the southern sub-belt. A 500-meter-thick sequence of cumulate gabbro is tectonically sandwiched between the peridotites and basalts. A 1- 2 km sequence of OIB-type basalt

  8. Application of integrated remote sensing and GIS technologies to geoenvironmental issues in far west Texas and southern New Mexico

    Science.gov (United States)

    Perez, Adriana Evangelina

    The primary goal of this dissertation was to utilize a geographic information system (GIS) to better understand geological, geophysical, forestry and environmental issues in the west Texas-New Mexico region. Studies such as these are especially important in the border region where economic limitations are usually a factor in studying and solving some of these problems. The availability of satellite imagery through the Pan-American Center for Earth and Environmental Studies (PACES), data from the Geospatial Center and the collaboration with the United States Department of Agriculture (USDA) and National Forest entities (Guadalupe and Lincoln Ranger Districts) enhance the value of our investigation. Research was conducted in two distinct areas: Cloudcroft-Ruidoso, New Mexico, and the Salt Flat basin of southwest Texas (Figure 1). The dissertation will be presented as a set of independent chapters. Chapter 1. A GIS and remote sensing investigation of the effects of interactions of terrain, soil, and other physiographic factors on the Pine Community of Lincoln National Park in the Sacramento Mountains of Southwest New Mexico. This study utilized GIS and remote sensing to better understand the dynamics of White Pine Blister Rust (WPBR) infestation in the white pine community of the Sacramento Mountains of southwest New Mexico. Both field spectral sampling of the needles and imagery analysis were incorporated to better understand the infestation, progression and vulnerability of the forest to this and other diseases. A major contribution of this study was to construct a GIS database, which was utilized to analyze USDA, elevation, satellite imagery, geological, and hydrological data to produce a hazard-rating map. The GIS environment also allowed for a 3-D perspective on the data, which was very useful in spatial visualization. Chapter 2. An integrated study of the basin structure of the Salt Flat basin. In this study we utilized, gravity and magnetic data, satellite

  9. The first cross sectional survey on intracranial malignancy in Kolkata, India: reflection of the state of the art in southern West Bengal.

    Science.gov (United States)

    Ghosh, Anirban; Sarkar, Susobhan; Begum, Zarina; Dutta, Shukla; Mukherjee, Joydeep; Bhattacharjee, Malabika; Sarkar, Pallab; Banerjee, Chandra; Mandal, Mousumi; Mazumdar, Anup; Bhattacharjee, Manoj Kumar; Chaudhuri, Samaresh; Chaudhuri, Swapna

    2004-01-01

    Recent increase in the occurrence of intracranial malignancies and poor performance of therapeutic measures have established the disease as an important concern of medical sciences. The lack of information about the disease pattern throughout India creates problems for maintaining community health for prevention. The present study on the hospital population of Kolkata was conducted to determine the incidence pattern of the disease in the population of southern West Bengal, focusing on distribution with age, sex, occupation and religion in different districts of the region, and characterizing diagnostic and therapeutic measures. Among a total of 39,509 cancer patients from 21 health centers of Kolkata, 2.4% had brain cancers and among these more than 60% are gliomas. A cross-sectional study for a period of 3 years reported the occurrence of 15 types of intracranial malignancy, which demonstrated astrocytomas (36.8%), glioblastoma multiforme (GBM) (7.9%) and meningiomas (11.6%) to be predominant. Brain tumors occur more frequently in males with few exceptions and the incidence was found to be highest among the 40-49 year old group (20.2%). No specific trend for religion and occupation was apparent. However, the district wise distribution showed maximum incidences among industrial areas, namely, Kolkata (33.1%), North 24-Parganas (18.2%), Howrah (9.3%) and Hoogly (7.6%). Diagnosis of the disease was by CT scan, MRI and histological identification (pre and post operative). Therapeutic procedures rely mainly on surgery and radiotherapy, whereas chemotherapy was used as an adjuvant for about 10% of the cases. Evaluation of the scenario regarding intracranial malignancy in this region was a long awaited requirement which should ultimately serve an important function in pointing to risk zones within the population and allow better control measures to be introduced for the disease. PMID:15373704

  10. Observations of Upwelling Filaments in the Southern North-West African Upwelling System : a Joint Effect of the Bottom Topography and the Offshore Eddy Field?

    Science.gov (United States)

    Meunier, T.; Barton, E. D.; Torres, R.; Barreiro, B.

    2010-12-01

    The nature and dynamics of the long filaments forming in the southern edge of the West-African upwelling system are investigated using data from the SOLAS-ICON cruise, that took place in April-May 2009 offshore of Cap Blanc, between 19.5 and 22.5 °N and 17 and 19 °W. Two synoptic hydrographic surveys using a Moving Vessel Profiler were performed at a 15 days interval on two distinct upwelling filaments at different stages of development. The first survey showed the presence of a large anticyconic eddy North of the filament, also evident in the satellite imagery. Two transects were performed across the tip of the filament, showing a steep rising of the isohalines and the isotherms, with horizontal gradients of 3.10-2 psu km-1 and 10 -1 °C km-1. The density compensation of temperature and salinity in this part of the North West African upwelling system resulted in a weaker doming of the isopycnals across the filament. The second filament developed during a strong wind episode directly following a 2 days wind relaxation period. 8 cross sections were performed, all showing a steeper doming of the isohalines and isotherms than during the first survey, resulting in horizontal gradients of 8.10-2 psu km-1 and 5.10-1 °C km-1 near the surface. The hydrographic signature of the filament was evident as deep as 300 m. Satellite imagery showed the persistence between the two surveys of a shorter and colder filament West of Cap Blanc , rolling around a small anticyclonic eddy, in spite of the relaxation of the wind. The surveyed filaments both appeared to emerge from this struc ture. A process study using a simple two layer shallow water isopycnic numerical model (MICOM) and an idealized topography was carried out to elucidate the development and stationarity of the anticyclone and cold filament at the root of the longer structures. Potential vorticity anomalies generated by topographic effects were shown to play a major role in the filament formation, when interacting with

  11. Magnetic fabric and petrology of Miocene sub-volcanic sills and dykes emplaced into the SW Flysch Belt of the West Carpathians (S Moravia, Czech Republic) and their volcanological and tectonic implications

    Czech Academy of Sciences Publication Activity Database

    Hrouda, F.; Buriánek, D.; Krejčí, O.; Chadima, Martin

    2015-01-01

    Roč. 290, č. 1 (2015), s. 38. ISSN 0377-0273 Institutional support: RVO:67985831 Keywords : Miocene volcanics * Outer Western Carpathian Flysch belt * magnetic fabric Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 2.543, year: 2014

  12. Climate history of the Southern Hemisphere Westerlies belt during the last glacial-interglacial transition revealed from lake water oxygen isotope reconstruction of Laguna Potrok Aike (52° S, Argentina

    Directory of Open Access Journals (Sweden)

    J. Zhu

    2014-05-01

    Full Text Available The Southern Hemisphere westerly winds (SHW play a crucial role in the large-scale ocean circulation and global carbon cycling. Accordingly, the reconstruction of its latitudinal position and intensity is essential for understanding global climatic fluctuations during the last glacial cycle. The southernmost part of the South American continent is of great importance for paleoclimate studies as the only continental mass intersecting a large part of the SHW belt. However, continuous proxy records back to the last Glacial are rare in southern Patagonia, owing to the Patagonian Ice Sheets expanding from the Andean area and the scarcity of continuous paleoclimate archives in extra-Andean Patagonia. Here, we present an oxygen isotope record from cellulose and purified bulk organic matter of aquatic moss shoots from the last glacial-interglacial transition preserved in the sediments of Laguna Potrok Aike (52° S, 70° W, a deep maar lake located in semi-arid, extra-Andean Patagonia. The highly significant correlation between oxygen isotope values of aquatic mosses and their host waters and the abundant well-preserved moss remains allow a high-resolution oxygen isotope reconstruction of lake water (δ18Olw for this lake. Long-term δ18Olw variations are mainly determined by δ18O changes of the source water of lake, surface air temperature and evaporative 18O enrichment. Under permafrost conditions during the Glacial, the groundwater may not be recharged by regional precipitation. The isolated groundwater could have had much less negative δ18O values than glacial precipitation. The less 18O depleted source water and prolonged lake water residence time caused by reduced interchange between in- and outflows could have resulted in the reconstructed glacial δ18Olw that was only ca. 3‰ lower than modern values. The significant two-step rise in reconstructed δ18Olw during the last deglaciation demonstrated the response of isotope composition of lake

  13. Early Silurian (~ 440 Ma) adakites and high-Nb basaltic rocks in the southern Altay Range (Northern Xinjiang): Slab melting and implications for crustal growth in the Central Asian Orogenic Belt

    Science.gov (United States)

    Shen, X.; Zhang, H.; Wang, Q.; Ma, L.

    2012-12-01

    As an important part of the Central Asian Orogenic Belt (CAOB), the Altay Range contain large-scale Paleozoic magmatic rocks. However, owing to lack of precise age constraints, the tectonic setting and petrogenesis of the magmatic rocks in this area have been controversial, which cause the debate on Phanerozoic crustal growth mechanism and accretionary orogenic processes in CAOB. Here we report geochronological and geochemical data of the Suoerkuduke adakites and associated high-Nb basaltic rocks in the southern margin of the southern Altay Range. LA-ICP-MS zircon U-Pb isotopic data for five adakite and high-Nb basaltic rock samples indicate that they were generated in the Early Silurian (~ 440 Ma). The adakites are geochemically characterized by high Na2O/K2O (1.3 to 16.7), Sr/Y (21 to 117), Al2O3 (13.0 to 18.3 wt.%), Sr (405 to 1813 ppm), ɛNd(t) (+3.6 to +6.5) and zircon ɛHf(t) (+10.8 to +18.9) values and relatively low (87Sr/86Sr)i ratios (0.7046 to 0.7049). The high-Nb basaltic rocks are sodium-rich (Na2O/K2O = 1.5-5.5) and have higher TiO2 (2.99 to 3.49 wt.%), P2O5 (1.09 to 1.56 wt.%), Zr (335 to 431 ppm), Nb (17.7 to 20.9 ppm), and Nb/U (11.7 to 30.2) values than those of typical arc basalts. They also have positive ɛNd(t) values (+5.4 to +8.4) and positive and variable zircon ɛHf(t) values (+0.71 - +16.9). We suggest that the Suoerkuduke adakites were derived by partial melting of subducted oceanic crust with minor overlying sediments, and the high-Nb basaltic rocks were possibly generated by partial melting of mantle wedge peridotite metasomatized by slab-derived adakitic melts and minor fluids. In combination with the occurrence of voluminous Silurian-Devonian granitoids, coeval ophiolite mélanges, and a series of intra-arc basins, a slab window model triggered by slab tearing or breakoff is proposed to interpret the formation of the Suoerkuduke adakite and high-Nb basaltic rock suites. The upwelling of asthenospheric mantle through the slab window

  14. Riding the belt

    Energy Technology Data Exchange (ETDEWEB)

    Potts, A.

    1998-04-01

    Recent developments in conveyor systems have focused on accessories rather than the belt itself. Radio frequency identification (RFID) is a technology using transponders embedded in conveyor belts and this is the latest development at the German firm Contitech. The system described in the articles developed with Moers, features transponders for cooling, controlling and monitoring conveyor belts. Other developments mentioned include a JOKI drum motor featuring a fully integrated gearbox and electric motor enclosed in a steel shell, from Interoll; a new scraper cleaning system from Hosch, new steel cord belting from Fenner, a conveying system for Schleenhain lignite opencast mine by FAM Foerdelantigen Magdeburg; new bearings from Nadella (the sales arm of Intersoll-Rand), an anti-shock belt transfer table from Rosta and new caliper disc brakes from GE Industrial.

  15. The Caucasian-Arabian segment of the Alpine-Himalayan collisional belt:Geology, volcanism and neotectonics

    Institute of Scientific and Technical Information of China (English)

    E. Sharkov; V. Lebedev; A. Chugaev; L. Zabarinskaya; A. Rodnikov; N. Sergeeva; I. Safonova

    2015-01-01

    The Caucasian-Arabian belt is part of the huge late Cenozoic Alpine-Himalayan orogenic belt formed by collision of continental plates. The belt consists of two domains:the Caucasian-Arabian Syntaxis (CAS) in the south and the EW-striking Greater Caucasus in the north. The CAS marks a zone of the indentation of the Arabian plate into the southern East European Craton. The Greater Caucasus Range is located in the south of the Eurasian plate;it was tectonically uplifted along the Main Caucasian Fault (MCF), which is, in turn, a part of a megafault extended over a great distance from the Kopetdag Mts. to the Tornquist-Teisseyre Trans-European Suture Zone. The Caucasus Mts. are bounded by the Black Sea from the west and by the Caspian Sea from the east. The SN-striking CAS is characterized by a large geophysical isostatic anomaly suggesting presence of mantle plume head. A 500 km long belt of late Cenozoic volcanism in the CAS extends from the eastern Anatolia to the Lesser and Greater Caucasus ranges. This belt hosts two different types of volcanic rocks: (1) plume-type intraplate basaltic plateaus and (2) suprasubduction-type calc-alkaline and shoshonite-latite volcanic rocks. As the CAS lacks signatures of subduction zones and is characterized by relatively shallow earthquakes (50e60 km), we suggest that the “supra-subduction-type”magmas were derived by interaction between mantle plume head and crustal material. Those hybrid melts were originated under conditions of collision-related deformation. During the late Cenozoic, the width of the CAS reduced to ca. 400 km due to tectonic “diffluence” of crustal material provided by the continuing Arabia-Eurasia collision.

  16. The Two Subduction Zones of the Southern Caribbean: Lithosphere Tearing and Continental Margin Recycling in the East, Flat Slab Subduction and Laramide-Style Uplifts in the West

    Science.gov (United States)

    Levander, A.; Bezada, M. J.; Niu, F.; Schmitz, M.

    2015-12-01

    The southern Caribbean plate boundary is a complex strike-slip fault system bounded by oppositely vergent subduction zones, the Antilles subduction zone in the east, and a currently locked Caribbean-South American subduction zone in the west (Bilham and Mencin, 2013). Finite-frequency teleseismic P-wave tomography images both the Atlanic (ATL) and the Caribbean (CAR) plates subducting steeply in opposite directions to transition zone depths under northern South America. Ps receiver functions show a depressed 660 discontinuity and thickened transition zone associated with each subducting plate. In the east the oceanic (ATL) part of the South American (SA) plate subducts westward beneath the CAR, initiating the El Pilar-San Sebastian strike slip system, a subduction-transform edge propagator (STEP) fault (Govers and Wortel, 2005). The point at which the ATL tears away from SA as it descends into the mantle is evidenced by the Paria cluster seismicity at depths of 60-110 km (Russo et al, 1993). Body wave tomography and lithosphere-asthenosphere boundary (LAB) thickness determined from Sp and Ps receiver functions and Rayleigh waves suggest that the descending ATL also viscously removes the bottom third to half of the SA continental margin lithospheric mantle as it descends. This has left thinned continental lithosphere under northern SA in the wake of the eastward migrating Antilles subduction zone. The thinned lithosphere occupies ~70% of the length of the El Pilar-San Sebastian fault system, from ~64oW to ~69oW, and extends inland several hundred kilometers. In northwestern SA the CAR subducts east-southeast at low angle under northern Colombia and western Venezuela. The subducting CAR is at least 200 km wide, extending from northernmost Colombia as far south as the Bucaramanga nest seismicity. The CAR descends steeply under Lake Maracaibo and the Merida Andes. This flat slab is associated with three Neogene basement cored, Laramide-style uplifts: the Santa Marta

  17. Vulnerability to climate change of cocoa in West Africa: Patterns, opportunities and limits to adaptation.

    Science.gov (United States)

    Schroth, Götz; Läderach, Peter; Martinez-Valle, Armando Isaac; Bunn, Christian; Jassogne, Laurence

    2016-06-15

    The West African cocoa belt, reaching from Sierra Leone to southern Cameroon, is the origin of about 70% of the world's cocoa (Theobroma cacao), which in turn is the basis of the livelihoods of about two million farmers. We analyze cocoa's vulnerability to climate change in the West African cocoa belt, based on climate projections for the 2050s of 19 Global Circulation Models under the Intergovernmental Panel on Climate Change intermediate emissions scenario RCP 6.0. We use a combination of a statistical model of climatic suitability (Maxent) and the analysis of individual, potentially limiting climate variables. We find that: 1) contrary to expectation, maximum dry season temperatures are projected to become as or more limiting for cocoa as dry season water availability; 2) to reduce the vulnerability of cocoa to excessive dry season temperatures, the systematic use of adaptation strategies like shade trees in cocoa farms will be necessary, in reversal of the current trend of shade reduction; 3) there is a strong differentiation of climate vulnerability within the cocoa belt, with the most vulnerable areas near the forest-savanna transition in Nigeria and eastern Côte d'Ivoire, and the least vulnerable areas in the southern parts of Cameroon, Ghana, Côte d'Ivoire and Liberia; 4) this spatial differentiation of climate vulnerability may lead to future shifts in cocoa production within the region, with the opportunity of partially compensating losses and gains, but also the risk of local production expansion leading to new deforestation. We conclude that adaptation strategies for cocoa in West Africa need to focus at several levels, from the consideration of tolerance to high temperatures in cocoa breeding programs, the promotion of shade trees in cocoa farms, to policies incentivizing the intensification of cocoa production on existing farms where future climate conditions permit and the establishment of new farms in already deforested areas. PMID:26974571

  18. The Glória quartz-monzodiorite: isotopic and chemical evidence of arc-related magmatism in the central part of the Paleoproterozoic Mineiro belt, Minas Gerais State, Brazil.

    Science.gov (United States)

    Avila, Ciro A; Teixeira, Wilson; Cordani, Umberto G; Barrueto, Héctor R; Pereira, Ronaldo M; Martins, Veridiana T S; Dunyi, Liu

    2006-09-01

    The Glória quartz-monzodiorite, one of the mafic plutons of the Paleoproterozoic Mineiro belt, is intrusive into banded gneisses, amphibolites, schists and phyllites of the Rio das Mortes greenstone belt, in the southern portion of the São Francisco Craton, State of Minas Gerais, Brazil. The Glória quartz-monzodiorite yields a SHRIMP U-Pb zircon age of 2188 +/- 29 Ma, suggesting a tectonic relationship with the pre-collisional phase of the Mineiro belt. According to the Nd isotopic evidence (epsilonNd(T) = -3.4; T DM = 2.68 Ga) the original magmas was formed by a mixture among Archean crustal material and Paleoproterozoic juvenile magma. The Glória quartz-monzodiorite shows metaluminous and calc-alkaline tendency with intermediate K content, comparable to that of volcanic-arc rocks. The primary mineralogical assemblage was partly modified by metamorphism, dated between 2131-2121 Ma in nearby coeval plutons. Such metamorphism is significantly older than the reported metamorphic episodes of the Mineiro belt in the Quadrilátero Ferrífero region (2059-2041 Ma) in the eastern portion of the study area. This evidence, together with chemical and isotopic data from other mafic and felsic plutons coeval with the Glória quartz-monzodiorite, indicate a tectonic and magmatic migration within the Mineiro belt from west to east. PMID:16936942

  19. Shallow crustal structure of eastern-central Trans-Mexican Volcanic Belt.

    Science.gov (United States)

    Campos-Enriquez, J. O.; Ramón, V. M.; Lermo-Samaniego, J.

    2015-12-01

    Central-eastern Trans-Mexican Volcanic Belt (TMVB) is featured by large basins (i.e., Toluca, Mexico, Puebla-Tlaxcala, Libres-Oriental). It has been supposed that major crustal faults limit these basins. Sierra de Las Cruces range separates the Toluca and Mexico basins. The Sierra Nevada range separates Mexico basin from the Puebla-Tlaxcala basin. Based in gravity and seismic data we inferred the Toluca basin is constituted by the Ixtlahuaca sub-basin, to the north, and the Toluca sub-basin to the south, which are separated by a relative structural high. The Toluca depression is more symmetric and bounded by sub-vertical faults. In particular its eastern master fault controlled the emplacement of Sierra de Las Cruces range. Easternmost Acambay graben constitutes the northern and deepest part of the Ixtlahuaca depression. The Toluca-Ixtlahuaca basin is inside the Taxco-San Miguel de Allende fault system, and limited to the west by the Guerrero terrane which continues beneath the TMVB up to the Acambay graben. Mexico basin basement occupies an intermediate position and featured by a relative structural high to the north-east, as established by previous studies. This relative structural high is limited to the west by the north-south Mixhuca trough, while to the south it is bounded by the east-west Copilco-Xochimilco-Chalco sub-basin. The Puebla-Tlaxcala basin basement is the shallowest of these 3 tectonic depressions. In general, features (i.e., depth) and relationship between these basins, from west to east, are controlled by the regional behavior of the Sierra Madre Oriental fold and thrust belt basement (i.e., Oaxaca Complex?). This study indicates that an active east-west regional fault system limits to the south the TMVB (from the Nevado de Toluca volcano through the Popocatepetl volcano and eastward along southern Puebla-Tlaxcala basin). The Tenango and La Pera fault systems constituting the western part of this regional fault system coincide with northern

  20. Mineral deposits of Southern Africa. V. 1-2

    International Nuclear Information System (INIS)

    This publication was needed to update our knowledge of the 'older' mineral deposits and mineral fields and to record in detail the geology of more recent discoveries. The discovery of copper over 300 years ago in Namaqualand was followed by even more dramatic finds - diamonds in the Kimberley area; gold and uranium in the Witwatersrand conglomerates; platinum, chromite, vanadium, iron, nickel and copper within certain horizons of the unique Bushveld Complex; iron, manganese and asbestos within the Transvaal sequence; and last, the large coal deposits within the Karoo sequence. This discoveries prompted further exploration which lead to the establishment of rich diamond mines in South West Africa/Namibia and Botswana, uranium in South West Africa/Namibia, nickel in Zimbabwe, and copper, tin and other base metal mines in other parts of Southern Africa. Volume one contains 79 papers. Two introductory papers are followed by 36 papers describing various Archaean mineral deposits. Volume two contains a 100 papers and commences with 25 papers dealing with aspects of mineralization. Descriptions of mineral deposits from various metamorphic mobile belts in Southern Africa are included in 22 papers. Late Proterozoic mineral deposits from South West Africa/Namibia are described in a series of 11 papers. The Phanerozoic deposits of the Karoo Sequence are discussed in 29 papers, followed by 7 papers describing mineralization associated with carbonatites and alkaline rocks. The final four papers discuss mineral occurences extending through to Recent Times, including present-day surficial deposits

  1. Origin of the Ediacaran Porongos Group, Dom Feliciano Belt, southern Brazilian Shield, with emphasis on whole rock and detrital zircon geochemistry and U-Pb, Lu-Hf isotopes

    Science.gov (United States)

    Pertille, Juliana; Hartmann, Léo Afraneo; Philipp, Ruy Paulo; Petry, Thales Sebben; de Carvalho Lana, Cristiano

    2015-12-01

    The Porongos Group is the major component of a fold and thrust belt located in the central portion of the Dom Feliciano Belt in the Sul-Riograndense Shield, Brazil. In this paper, the variations in composition of sediments and the depositional time are presented. Major and trace elements indicate that Porongos Group is composed mostly of immature sediments derived from intermediate felsic sources with minor contribution from mature recycled sources. U-Pb SHRIMP ages for a chlorite schist (sample 300) exhibit a proeminent population of 570-800 Ma, subordinate population of 1800-2250 Ma and minor population of 1200 Ma, whereas for a schist (sample 198) the main population is 1050-1500 and minor populations are 2040-2300 and 580-800 Ma. The ɛHf values of Neoproterozoic grains indicate variable degrees of crustal reworking (ɛHf = -18 to -4) with three main TDM model ages (2.2, 1.8, 1.5 Ga). The Paleoproterozoic grains include a few Archean (3.2-2.5 Ga) TDM ages. The trace elements of all analyzed detrital zircon grains reflect continental crust origin. According to the data set, the sediments of the Porongos Group were derived from locally eroded granitic rocks of the Dom Feliciano Belt and from the uplifted Paleoproterozoic basement (La Plata Craton). Further analytical signal and total magnetic field maps delimit regionally the shape and extension of the Porongos fold and thrust belt and includes the Capané region. We conclude that the duration of Porongos Group basin filling probably lasted from 650 to 570 Ma in a foreland tectonic setting of the Dom Feliciano Belt.

  2. Denudation History and Paleogeographic Reconstruction of the Phanerozoic of southern Mantiqueira Province, Brazil

    Science.gov (United States)

    Jelinek, A. R.; Chemale, F., Jr.

    2012-12-01

    In this work we deal with the Phanerozoic history of the Southern Mantiqueira Province and adjacent areas after the orogen-collapse of the Brasiliano orogenic mountains in southern Brazil and Uruguay, based on thermocronological data (fission track and U-Th/He on apatite) and thermal history modelling. During the Paleozoic intraplate sedimentary basins formed mainly bordering the orogenic systems, and thus, these regions have not been overprinted by younger orogenic processes. In the Mesocenozoic this region was affected by later fragmentation and dispersal due to the separation of South America and Africa. Denudation history of both margins quantified on the basis of thermal history modeling of apatite fission track thermocronology indicates that the margin of southeastern Brazil and Uruguay presented a minimum 3.5 to 4.5 Km of denudation, which included the main exposure area of the Brasiliano orogenic belts and adjacent areas. The Phanerozoic evolution of the West Gondawana is thus recorded first by the orogenetic collapses of the Brasiliano and Pan-African belts, at that time formed a single mountain system in the Cambrian-Ordovician period. Subsequentlly, formed the intraplate basins as Paraná, in southeastern Brazil, and Congo and some records of the Table Mountains Group and upper section of Karoo units, in Southwestern Africa. In Permotriassic period, the collision of the Cape Fold Belt and Sierra de la Ventana Belt at the margins of the West Gondwana supercontinent resulted an elastic deformation in the cratonic areas, where the intraplate depositional basin occurred, and also subsidence and uplift of the already established Pan-African-Brasiliano Belts. Younger denudation events, due to continental margin uplift and basin subsidence, occurred during the rifting and dispersal of the South America and Africa plates, which can be very well defined by the integration of the passive-margin sedimentation of the Pelotas and Santos basins and apatite fission

  3. Planck intermediate results. XII: Diffuse Galactic components in the Gould Belt System

    DEFF Research Database (Denmark)

    Planck Collaboration,; Ade, P. A. R.; Aghanim, N.;

    2013-01-01

    We perform an analysis of the diffuse low-frequency Galactic components in the Southern part of the Gould Belt system (130^\\circ\\leq l\\leq 230^\\circ and -50^\\circ\\leq b\\leq -10^\\circ). Strong ultra-violet (UV) flux coming from the Gould Belt super-association is responsible for bright diffuse for...

  4. A belted kingfisher flies above KSC

    Science.gov (United States)

    1999-01-01

    A belted kingfisher soars over the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. The pigeon-sized, blue-gray male is identified by the blue-gray breast band; females show a chestnut belly band. The belted kingfisher ranges throughout the United States and Canada, wintering south to Panama and the West Indies. They dive into the water for fish and may also take crabs, crayfish, salamanders, lizards, mice and insects. The 92,000-acre refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

  5. Geometry, kinematics and evolution of the Tongbai orogenic belt

    Institute of Scientific and Technical Information of China (English)

    HUANG Shaoying; XU Bei; WANG Changqiu; ZHAN Sheng; DENG Rongjing

    2006-01-01

    The Tongbai orogenic belt (TOB) is composed of six tectonic units. From south to north these units are: Tongbai gneiss rise (TGR); Hongyihe-Luozhuang eclogite belt (HLE); Maopo-Hujiazhai igneous rock belt (MHI); Zhoujiawan flysch belt (ZFB); Yangzhuang greenschist belt (YGB); and Dongjiazhuang marble belt (DMB).The geometry and kinematic images of the TOB include: the antiformal structures caused by a later uplift process, the top-to-north ductile shear structure that related to a process that the ultrahigh pressure rocks are brought to surface, the top-to-south ductile shear thrust and the sinistrial shear structures related to a south-north direction compression, and the east-west direction fold structures in the upper crust. In the view of the multistage subduction-collision orogenic belt, according to the characters of petrology and its distribution, geometry, kinematics and structural chronology in these tectonic units, tectonic evolution of the TOB can be divided into four stages: oceanic crust subduction during 400-300 Ma, continental collision during 270-250 Ma, continental deep subduction and uplift during 250-205 Ma and doming deformation during 200-185 Ma.

  6. Dynamic characteristics of conveyor belts

    Institute of Scientific and Technical Information of China (English)

    HOU You-fu; MENG Qing-rui

    2008-01-01

    The dynamic characteristics of a belt conveyor are determined to a large extent by the properties of the belt. This paper describes experiments designed to establish the dynamic properties of belting material. The dynamic elastic modulus, viscous damping and theological constants of the belt were measured. Several properties were studied as a function of the tensile loading on the belt. These included longitudinal vibration, the natural vibration frequency in the transverse direction and the response to an impulse excitation. Vibration response was observed under several different excitation frequencies. Most of these properties have not been tested previously under conditions appropriate for the ISO/DP9856 standard. Two types of belt were tested, a steel reinforced belt and a fabric reinforced belt. The test equipment was built to provide data appropriate for designing belt conveyors. It was observed that the stress wave propagation speed increased with tensile load and that tensile load was the main factor influencing longitudinal vibrations.

  7. The Namuskluft and Dreigratberg sections in southern Namibia (Kalahari Craton, Gariep Belt): a geological history of Neoproterozoic rifting and recycling of cratonic crust during the dispersal of Rodinia until the amalgamation of Gondwana

    Science.gov (United States)

    Hofmann, Mandy; Linnemann, Ulf; Hoffmann, Karl-Heinz; Gerdes, Axel; Eckelmann, Katja; Gärtner, Andreas

    2014-07-01

    This paper presents combined U/Pb, Th/U and Hf isotope analyses on detrital and magmatic zircon grains together with whole-rock geochemical analyses of two basement and eight sedimentary rock samples from the Namuskluft and the Dreigratberg in southern Namibia (Gariep Belt). The sedimentary sections evolved during the Cryogenian on the SW part of the Kalahari Craton and where therefore deposited in an active rift setting during the break-up of Rodinia. Due to insufficient palaeomagnetic data, the position of the Kalahari Craton within Rodinia is still under discussion. There are possibilities to locate Kalahari along the western side of Australia/Mawsonland (Pisarevski et al. in Proterozoic East Gondwana: supercontinent assembly and break-up, Geological Society, London, 2003; Evans in Ancient Orogens and modern analogues. Geological Society, London, 2009; and others) or together with the Congo-Sao Francisco and Rio de la Plata Cratons (Li et al. in Prec Res 45: 203-2014, 2008; Frimmel et al. in Int J Earth Sci (Geol Rundsch) 100: 323-354, 2011; and others). It is sill unclear which craton rifted away from the Kalahari Craton during the Cryogenian. Although Middle to Upper Cryogenian magmatic activity is known for the SE Kalahari Craton (our working area) (Richtersveld Suite, Rosh Pinah Fm), all the presented samples show no U/Pb zircon ages younger than ca. 1.0 Ga and non-older than 2.06 Ga. The obtained U/Pb ages fit very well to the exposed basement of the Kalahari Craton (1.0-1.4 Ga Namaqua Province, 1.7-2.0 Ga Vioolsdrif Granite Suite and Orange River Group) and allow no correlation with a foreign craton such as the Rio de la Plata or Australia/Mawsonland. Lu-Hf isotopic signatures of detrital zircon point to the recycling of mainly Palaeoproterozoic and to a smaller amount of Archean crust in the source areas. ɛHf( t) signatures range between -24 and +14.8, which relate to TDM model ages between 1.05 and 3.1 Ga. Only few detrital zircon grains derived from

  8. The Analysis of Metamorphism-deformation Sequence for the Paired Metamorphic Belt in West Tianshan Orogen:An Example from Chahanwusu Area,Zhaosu County,Xinjiang%西天山造山带双变质带变质变形序列分析--以新疆昭苏县察汗乌苏一带为例

    Institute of Scientific and Technical Information of China (English)

    程培起

    2015-01-01

    西天山造山带中双变质带以新疆昭苏察汗乌苏一带较为典型,根据变质作用的不同,划分出绿片岩相绢云母绿泥石带、绿片岩相蓝闪石带、角闪岩相黑云母普通角闪石带、角闪岩相矽线石铁铝榴石带等变质相带;按其变质作用以及构造变形程度分为上部层次脆性性构造层、中上部层次、深部层次3种构造层次。根据之间的相互叠加关系,确立了造山带内的岩石主要存在着3期以上构造变形特征;在主要的3期构造变形过程中见有相应的变质矿物,并根据生成的矿物组合与变形之间的相互关系,通过变质矿物先后生成关系与岩石的结构、构造建立了变质与变形序列关系,确立了变质与变形非简单一一对应,而是具有渗透叠加和循环往复的特点。%The paired metamorphic belt of West Tianshan Orogen is more typical in Chahanwusu Area,Xinjiang. According to the difference of metamorphism,this paired metamorphic belt can be divided into several metamorphic facies zone,including sericite-chlorite zone with greeanschist-facies,glaucophane zone with greenschist facies,biotite-hornblende zone with amphibolite facies belt and sillimanite-almandite zone with amphibolite facies. Based on the degree of metamorphism and tectonic deformation,this paired metamorphic belt can be divided into three kinds of structur-al levels:the brittle structural layer in the upper level,the structural layers in the middle-upper level and the ones in the lower level. After analyzing the superimposed relationship among these structural levels,more than threetimes of tectonic deformation characteristics have been distin-guished in the rocks of West Tianshan Orogen. And the corresponding metamorphic minerals for these three tectonic stages in the process of deformation can be observed. And then,the interre-lationship between generated mineral association and deformation has been discussed,the rela

  9. The JET belt limiter

    International Nuclear Information System (INIS)

    A limiter with an effective area in contact with the plasma of about 16 m2 is presently being manufactured for installation in 1987. This belt limiter consists of two toroidal rings located above and below the equatorial plane of the vacuum vessel. Each of the two rings comprises a structure with water cooling pipes and fins welded to the pipes. The limiter material in contact with the plasma (graphite or beryllium) is inserted between fins in the form of tiles. The belt limiter is designed to handle up to 40 MW of total power at flux densities of 3 - 5 MW/m2 for 10 s and to permit rapid exchange of different limiter materials. The design and manufacture of the belt limiter and the results of thermomechanical analysis for different edge properties, power levels and shot repetition rates, are reported. (author)

  10. The jet belt limiter

    International Nuclear Information System (INIS)

    A limiter with an effective area in contact with the plasma of about 16 m/sup 2/ is presently being manufactured for installation in 1987. This belt limiter consists of two toroidal rings located above and below the equatorial plane of the vacuum vessel. Each of the two rings comprises a structure with water cooling pipes and fins welded to the pipes. The limiter material in contact with the plasma (graphite or beryllium) is inserted between fins in the form of tiles. The belt limiter is designed to handle up to 40 MW of total power at flux densities of 3 - 5 MW/m/sup 2/ for 10 s and to permit rapid exchange of different limiter materials. This paper describes the design and manufacture of the belt limiter and the results of thermomechanical analysis for different edge properties, power levels and shot repetition rates

  11. Black-tailed Godwit Demographic Project - Why should Black-tailed Godwits still winter in West-Africa if Southern Iberia is just as good?

    NARCIS (Netherlands)

    Hooijmeijer, Joslyn; Valkema, Haije; Loos, Bob; Piersma, Theun

    2014-01-01

    In November 2014 the University of Groningen, in cooperation with Global Flyway Network and financially supported by Birdlife Netherlands, embarked upon a 19 days expedition to the wintering grounds in West-Africa. We aim to set up a demographic research project in this area. Most important goal of

  12. Three years of aircraft-based trace gas measurements over the Fyodorovskoye southern taiga forest, 300 km north-west of Moscow

    NARCIS (Netherlands)

    Ramonet, M.; Ciais, P.; Nepomniachii, I.; Sidorov, K.; Neubert, R.E.M.; Langendörfer, U.; Picard, D.; Kazan, V.; Biraud, S.; Gusti, M.; Kolle, O.; Schulze, E.-D.; Lloyd, J.

    2002-01-01

    As part of the Eurosiberian Carbonflux project, regular measurements have been performed in the lower troposphere over a southern taiga forest area in Fyodorovskoye, Western Russia (56°28'N, 32°56'E). Up to 70 flights have been made between May 1998 and December 2000, plus additional intensive campa

  13. Coal belt options

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-03-15

    Whether moving coal long distances overland or short distances in-plant, belt conveyors will always be in demand. The article reports on recent systems developments and applications by Beumer, Horizon Conveyor Equipment, Conveyor Dynamics, Doppelmayr Transport Technology, Enclosed Bulk Systems, ContiTech and Bateman Engineered Technologies. 2 photos.

  14. Cenozoic intracontinental deformation of the Kopeh Dagh Belt, Northeastern Iran

    Science.gov (United States)

    Chu, Yang; Wan, Bo; Chen, Ling; Talebian, Morteza

    2016-04-01

    Compressional intracontinental orogens represent large tectonic zones far from plate boundaries. Since intracontinental mountain belts cannot be framed in the conventional plate tectonics theory, several hypotheses have been proposed to account for the formations of these mountain belts. The far-field effect of collision/subduction at plate margins is now well accepted for the origin and evolution of the intracontinental crust thickening, as exemplified by the Miocene tectonics of central Asia. In northern Iran, the Binalud-Alborz mountain belt witnessed the Triassic tectonothermal events (Cimmerian orogeny), which are interpreted as the result of the Paleotethys Ocean closure between the Eurasia and Central Iran blocks. The Kopeh Dagh Belt, located to the north of the Binalud-Alborz Belt, has experienced two significant tectonic phases: (1) Jurassic to Eocene rifting with more than 7 km of sediments; and (2) Late Eocene-Early Oligocene to Quaternary continuous compression. Due to the high seismicity, deformation associated with earthquakes has received more and more attention; however, the deformation pattern and architecture of this range remain poorly understood. Detailed field observations on the Cenozoic deformation indicate that the Kopeh Dagh Belt can be divided into a western zone and an eastern zone, separated by a series of dextral strike-slip faults, i.e. the Bakharden-Quchan Fault System. The eastern zone characterized by km-scale box-fold structures, associated with southwest-dipping reverse faults and top-to-the NE kinematics. In contrast, the western zone shows top-to-the SW kinematics, and the deformation intensifies from NE to SW. In the northern part of this zone, large-scale asymmetrical anticlines exhibit SW-directed vergence with subordinate thrusts and folds, whereas symmetrical anticlines are observed in the southern part. In regard to its tectonic feature, the Kopeh Dagh Belt is a typical Cenozoic intracontinental belt without ophiolites or

  15. Araguaia fold belt, new geochronological data

    International Nuclear Information System (INIS)

    The northern part of the Araguaia Fold Belt (AFB) outcrops in a N-S direction for about 400 km in the state of Tocantins. Dome-like structures occur in this fold belt also in a N-S direction. Both deformation and metamorphism increase from the West to the East. The basement of the AFB consist of Colmeia complex and Cantao gneiss, which crop out mainly in the core of the dome-like structures. The supracrustals rocks of the fold belt belongs to the Baixo Araguaia supergroup which is divided into the lower Estrondo group and the upper Tocantins group. Preliminary Sm-Nd data from the Colmeia complex (Grota Rica dome) gave Archean model ages of 2.8 Ga (TNd sub(DM)) while Rb-Sr data in the same rocks give an age of 2530 ± 200 Ma. In the others dome-like structures, the Rb-Sr systematics gave ages for the Colmeia a complex of 2239 ± 47 Ma (Colmeia structure) and 1972 ± 46 Ma (Lontra structure). These younger ages are believed to represent partial to total isotopic resetting of the Rb-Sr system during the Transamazonian Event. The Rb-Sr studies of the Cantao gneiss gave an age of 1774 ± 31 Ma. (author)

  16. Tropical cyclone Dera, the unusual 2000/01 tropical cyclone season in the South West Indian Ocean and associated rainfall anomalies over Southern Africa

    Science.gov (United States)

    Struchtrup, Henning; Thatcher, Toby

    2007-08-01

    Austral summer 2000/01 in the southern African region was unusual in several respects. Tropical cyclone activity in the southwest Indian Ocean was substantially less than average despite large areas of this region showing anomalously warm sea surface temperatures (SST) for much of the season. Many areas of southern Africa experienced above average rainfall with local flooding in parts of Mozambique. In the tropical southeast Atlantic, a large warm SST anomaly evolved off the coast of Angola and northern Namibia in late summer suggesting a Benguela Niño event. During the late summer (February April 2001), three particularly widespread and intense wet spells occurred over tropical southern Africa, one of which coincided with tropical cyclone Dera. This study considers the generation and evolution of the middle wet spell of late summer 2001 and its relationship with tropical cyclone Dera. This storm was generated in the northwestern part of the Mozambique Channel and then tracked more or less due south through the Channel and into the subtropical southwest Indian Ocean. Rainfall associated with Dera contributed to the ongoing floods over central Mozambique that arose from rains earlier in the season. Dera occurred in early March following a relatively long period of no tropical cyclone activity in the southwest Indian Ocean. A build up of favorable conditions during the preceding weeks contributed towards the storm whereas an anticyclonic anomaly east of Madagascar led to the northerly steering current and the southward track of tropical cyclone Dera out of the Mozambique Channel.

  17. Geochemistry of metavolcanics from the Neoproterozoic Tuludimtu orogenic belt, western Ethiopia

    Science.gov (United States)

    Tadesse, Gebremedhin; Allen, Alistair

    2004-06-01

    The 200 km wide Tuludimtu Belt of Western Ethiopia is one of a series of N-S trending Neoproterozoic orogenic belts of the East African Orogenic Province in southeastern Sudan and western and southern Ethiopia. The Tuludimtu Belt consists of deformed greenschist facies metasediments and metavolcanics, flanked to the east and west by gneissic terranes, all of which are invaded by pre-, syn- and post-tectonic intrusives ranging from ultramafic to felsic in composition. The Tuludimtu Belt has been subdivided into five lithotectonic domains, from east to west, the Didesa, Kemashi, Dengi, Sirkole and Daka Domains. On the basis of lithological associations, the three domains in the core of the belt, the Kemashi, Dengi and Sirkole Domains, are respectively interpreted to represent an ophiolitic terrane of oceanic crustal origin, a volcanic arc, and a fold-thrust terrane composed of interleaved thrust sheets of gneissic basement and cover strata. The Didesa and Daka Domains are composed of moderate- to high-grade gneisses, possibly representing the basement forelands to the belt. Major and trace element geochemistry for metavolcanics of predominantly basaltic and andesitic composition from the Kemashi, Dengi and Didesa Domains, are presented, and a preliminary analysis of the data undertaken. Two suites of metavolcanics are clearly differentiated by the discrimination diagrams. The samples from all three domains are predominantly tholeiitic, subalkaline basalts and andesites. Bivariate plots reveal weak negative correlations of SiO 2 and Al 2O 3 with MgO, and a positive correlation of CaO with MgO, indicating that magmas evolved by fractionation of clinopyroxene, orthopyroxene and olivine from the parent liquids. Trace element spider diagrams show a tight coherence of patterns for the Dengi and Sirkole samples, suggestive that alteration did not accompany metamorphic processes to any great extent, and a slight depletion of HFS elements possibly due to fractionation

  18. Infrared Kuiper Belt Constraints

    International Nuclear Information System (INIS)

    We compute the temperature and IR signal of particles of radius a and albedo α at heliocentric distance R, taking into account the emissivity effect, and give an interpolating formula for the result. We compare with analyses of COBE DIRBE data by others (including recent detection of the cosmic IR background) for various values of heliocentric distance R, particle radius a, and particle albedo α. We then apply these results to a recently developed picture of the Kuiper belt as a two-sector disk with a nearby, low-density sector (40< R<50 endash 90 AU) and a more distant sector with a higher density. We consider the case in which passage through a molecular cloud essentially cleans the solar system of dust. We apply a simple model of dust production by comet collisions and removal by the Poynting-Robertson effect to find limits on total and dust masses in the near and far sectors as a function of time since such a passage. Finally, we compare Kuiper belt IR spectra for various parameter values. Results of this work include: (1) numerical limits on Kuiper belt dust as a function of (R, a, α) on the basis of four alternative sets of constraints, including those following from recent discovery of the cosmic IR background by Hauser et al.; (2) application to the two-sector Kuiper belt model, finding mass limits and spectrum shape for different values of relevant parameters including dependence on time elapsed since last passage through a molecular cloud cleared the outer solar system of dust; and (3) potential use of spectral information to determine time since last passage of the Sun through a giant molecular cloud. copyright copyright 1999. The American Astronomical Society

  19. Belt-up!

    Energy Technology Data Exchange (ETDEWEB)

    Woof, M.

    1999-07-01

    Advanced control systems, improved materials and new dust control systems have turned the humble conveyor belt into a sophisticated method for transporting materials. RJB Mining has improved productivity at the Price of Wales colliery in Yorkshire, UK, with the installation of Alstom`s VDM drive system; Qualter Hall`s upgraded conveyor system at the Rugely Power Station in the UK is proving its ability to minimise coal spillage. The article highlights advances by several manufacturers in conveyor technology. 5 photos.

  20. The Late Paleozoic Southern Margin of the Siberian paleocontinent: transformation from an active continental margin to intracontinental rifting

    Science.gov (United States)

    Kozlovsky, A. M.; Yarmolyuk, V. V.; Sal'Nikova, E. B.

    2009-04-01

    The large volcanoplutonic belt was formed on the southern margin of Siberian paleocontinent in the Early Carboniferous-Early Permian. Now it's stretched through whole Mongolia and the adjacent region of China. In the belt structure there are defined the successive rock complexes: the older one represented by differentiated basalt-andesite-rhyodacite series and younger bimodal complex of basalt-comendite-trachyrhyolite composition. The granodiorite-plagiogranite and diorite-monzonite-granodiorite plutonic massifs are associated with the former, while peralkaline granite massifs are characteristic of the latter. Geochronological results and geological relations between rocks of the bimodal and differentiated complexes showed first that rocks of the differentiated complex originated 350 to 330 Ma ago at the initial stage of forming of the marginal continental belt, linked with development active continental margin. This is evident from geochronological dates obtained for the Adzh-Bogd and Edrengiyn-Nuruu massifs and for volcanic associations of the complex. The dates are consistent with paleontological data. The bimodal association was formed later, 320 to 290 Ma ago. The time span separating formation of two igneous complexes ranges from several to 20-30 m.y. in different areas of the marginal belt. The bimodal magmatism was interrelated with rifting responsible for development of the Gobi-Tien Shan rift zone in the belt axial part and the Main Mongolian lineament along the belt northern boundary. Loci of bimodal rift magmatism likely migrated with time: the respective magmatic activity first initiated on the west of the rift system and then advanced gradually eastward with development of rift structures. Normal granitoids untypical but occurring nevertheless among the products of rift magmatism in addition to peralkaline massifs are assumed to have been formed, when the basic magmatism associated with rifting stimulated crustal anatexis and generation of crustal

  1. Ignimbrite Flare-up in the North-Central Sierra Madre del Sur, Southern Mexico: a Continuation of the Sierra Madre Occidental Ignimbrite Province?

    Science.gov (United States)

    Moran-Zenteno, D. J.; Alba-Aldave, L.; Gonzalez-Torres, E. A.; Martiny, B.; Bravo-Diaz, B. A.; Sohn, E.

    2007-05-01

    The north-central Sierra Madre del Sur, immediately south of the Trans Mexican Volcanic Belt, is made up of a series of Eocene silicic volcanic centers distributed along a WNW trending 300 km long belt from Valle de Bravo to Huautla (98°50'-100°30'W longitude). This belt constitutes an inland arc near parallel to, and coeval with, the coastal batholitic belt of southern Mexico. It includes at least 9 exhumed volcanic edifices that display diverse caldera styles controlled by regional fracture zones and rheological contrasts in the host rocks. Initiation of the volcanism ranges from 37 Ma in the west to 32 Ma in the east, and extinction of magmatism was nearly simultaneous in the eastern half of the belt. Southwest of the silicic volcanic belt, andesitic volcanism is slightly younger (33-29 Ma) and the combined effect of post-Eocene uplift and erosion removed most of the extracaldera facies. The remnants of the silicic volcanic cover extend over an area of ~3000 km2. Reactivated fracture zones related to the volcanic activity include NW to W- trending faults that reveal a transition from left lateral to right lateral slip as result of a change in the stress field during the last stages of silicic volcanism. These and other groups of N-S to NNW trending faults accommodated the collapse structures and were the sites of emplacement of massive pyroclastic dikes. Immediately north of the Trans Mexican Volcanic Belt, ignimbrites and related rocks of the Mesa Central and southern Sierra Madre Occidental are slightly younger and display a westward 30 to ~15 Ma migration pattern accompanied by E-W regional extension. These patterns have been attributed to the roll back of the subducted slab, which caused the ascent of asthenospheric mantle and probably triggered ignimbrite flare-up. The distinct tectonic and geochronologic patterns of the arc volcanic rocks in the northern Sierra Madre del Sur and the southern Sierra Madre Occidental-Mesa Central suggests two slab segments

  2. Climate history of the Southern Hemisphere Westerlies belt during the last glacial-interglacial transition revealed from lake water oxygen isotope reconstruction of Laguna Potrok Aike (52° S, Argentina)

    OpenAIRE

    J. Zhu; A. Lücke; H. Wissel; Mayr, C.; D. Enters; Kim, K. J.; C. Ohlendorf; F. Schäbitz; B. Zolitschka

    2014-01-01

    The Southern Hemisphere westerly winds (SHW) play a crucial role in the large-scale ocean circulation and global carbon cycling. Accordingly, the reconstruction of its latitudinal position and intensity is essential for understanding global climatic fluctuations during the last glacial cycle. The southernmost part of the South American continent is of great importance for paleoclimate studies as the only continental mass intersecting a large part of the SHW ...

  3. Three Alkali—Rich Intrusive Rock Belts Bewly Discovered in the Mt.Kunlkun—Mt.Altun Region,Xinjiang,China

    Institute of Scientific and Technical Information of China (English)

    朱笑青; 王元龙; 等

    2002-01-01

    The newly discovered three alkali-rich intrusive rock belts in the Mt.Kunlun Mt.Altun region of southern Xinjiang are the Lapeiquan-Yitunbulak alkali-rich intrusive fock belt, the Gez-Taxkorgan alkali-rich intrusive rock belt and the Beeilisai-Abulash alkali-rich intrusive rock belt.The former two belts were formed during the Yanshanian period,and the third one was formed during the Himalayan period,which is the youngest alkali-rich intrusive rock belt in China.The discovery of the alkali-rich intrusive rock belts is of great significance in shedding light on the history of tectono-magmatic activities in this region.

  4. Three Alkali-Rich Intrusive Rock Belts Newly Discovered in the Mt. Kunlun-Mt. Altun Region, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    朱笑青; 王元龙; 毕华; 王中刚

    2002-01-01

    The newly discovered three alkali-rich intrusive rock belts in the Mt. Kunlun Mt.Altun region of southern Xinjiang are the Lapeiquan-Yitunbulak alkali-rich intrusive rock belt,the Gez-Taxkorgan alkali-rich intrusive rock belt and the Beilisai-Abulash alkali-rich intrusive rock belt. The former two belts were formed during the Yanshanian period, and the third one was formed during the Himalayan period, which is the youngest alkali-rich intrusive rock belt in China. The discovery of the alkali-rich intrusive rock belts is of great significance in shedding light on the history of tectono-magmatic activities in this region.

  5. Lap belt injuries in children.

    LENUS (Irish Health Repository)

    McGrath, N

    2010-07-01

    The use of adult seat belts without booster seats in young children may lead to severe abdominal, lumbar or cervical spine and head and neck injuries. We describe four characteristic cases of lap belt injuries presenting to a tertiary children\\'s hospital over the past year in addition to a review of the current literature. These four cases of spinal cord injury, resulting in significant long-term morbidity in the two survivors and death in one child, arose as a result of lap belt injury. These complex injuries are caused by rapid deceleration characteristic of high impact crashes, resulting in sudden flexion of the upper body around the fixed lap belt, and consequent compression of the abdominal viscera between the lap belt and spine. This report highlights the dangers of using lap belts only without shoulder straps. Age-appropriate child restraint in cars will prevent these injuries.

  6. Belt conveyor for recycle aggregate

    OpenAIRE

    Bezrodný, Roman

    2014-01-01

    This bachelor thesis deals with the belt conveyor for the transport of recycled aggregate in an oblique direction. The aim is to find constructional solutions to the belt conveyor for the assigned transport capacity of 95 000 kg per hour, and the assigned axial distance of 49 m and different height of 12 m. The thesis contains a brief description of the belt conveyor and a description of basic constructional components. It also contains a functional calculation of the capacity and forces acco...

  7. Three years of aircraft-based trace gas measurements over the Fyodorovskoye southern taiga forest, 300 km north-west of Moscow

    International Nuclear Information System (INIS)

    As part of the EUROSIBERIAN CARBONFLUX project, regular measurements have been performed in the lower troposphere over a southern taiga forest area in Fyodorovskoye, Western Russia (56 deg 28 min N, 32 deg 56 min E). Up to 70 flights have been made between May 1998 and December 2000, plus additional intensive campaigns to study the diurnal variability of atmospheric trace gases within the boundary layer. We sampled flasks between 100 and 3000 m for analysis of CO2, (delta) 13C and (delta) 18O in CO2, CH4 and CO. In addition, in-situ CO2, relative humidity, pressure and temperature were performed for a better description of the vertical variability and accurate determination of the boundary layer height. The peak-to-peak amplitude of the seasonal cycle of atmospheric CO2 within the boundary layer of 26.5 ppm is about twice the one observed in the free troposphere (14.6 ppm). The spring draw down of CO2 also occurs one month earlier than in the free troposphere aloft. There is also an increase by factor of two in the vertical variability of CO2 within the free troposphere between summer and winter, which may be related to the variability of advection and mixing. Linear regression analysis applied to flask measurements of CO, CH4 and (delta) 13C versus CO2 in the free troposphere indicates that industrial emissions over Europe are a dominant source of synoptic variability in wintertime in air masses reaching Fyodorovskoye. On the other hand, the variability of trace gases in the boundary layer observed during intensive campaigns is consistent with the patterns of proximate sources over the underlying southern taiga landscape at Fyodorovskoye

  8. SLH Timing Belt Powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Abe

    2014-04-09

    The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

  9. Scheelite distribution a long of amphibolitic belt from greenstone belt Barbacena, Minas Gerais, Brazil

    International Nuclear Information System (INIS)

    In the middle southern portion of the Minas Gerais state a 60 Km long and 12 Km wide tungsten belt was discovered, and related to the amphibolitic rocks of the Barbacena Greenstone. Tungsten, present as scheelite, is associated with amphibolites, amphibole schists and amphibole gneisses, with chemical characteristics indicating an igneous origin. Chemical analyses on pan concentrates by I.C.P. showed high values on lead, tin, yttrium, lanthanum, cerium and zirconium, and average values for zinc and copper. The scheelite mineralization is probably strata bound and has a possible submarine exhalative origin. (author)

  10. Geodynamic evolution of the West Africa between 2.2 and 2 Ga: the Archaean style of the Birimian greenstone belts and the sedimentary basins in northeastern Ivory-Coast; Evolution de l`Afrique de l`Ouest entre 2,2 Ga et 2 Ga: le style archeen des ceintures vertes et des ensembles sedimentaires birimiens du nord-est de la Cote-d`Ivoire

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, M.; Pouclet, A. [Orleans Univ., 45 (France); Delor, C. [Bureau de Recherches Geologiques et Minieres (BRGM), 45 - Orleans (France); Simeon, Y. [ANTEA, 45 - Orleans (France); Alric, G. [Etablissements Binou, 27 - Le Mesnil-Fuguet (France)

    1996-12-31

    The litho-structural features of Palaeo-proterozoic terrains of northeastern Ivory-Coast, greenstones belts and then sedimentary (basin Birimian), are similar to those of Archaean terrains. Their early deformation is only voluminal deformation due to granitoid intrusions, mainly between 2.2 and 2.16 Ga. The shortening deformation (main deformation) is expressed by right folds and transcurrent shear zones ca 2.1 Ga. Neither thrust deformation nor high pressure metamorphic assemblages are known. This pattern of flexible and hot crust, at least between 2.2 and 2.16 Ga, is pole apart to a collisional pattern, proposed for West African Craton by some authors. The Archaean/Palaeo-proterozoic boundary would not represent a drastic change of the geodynamic evolution of the crust. (authors). 60 refs., 5 figs., 6 photos.

  11. Metamorphism and plutonism in the Quetico Belt, Superior Province, N.W. Ontario

    Science.gov (United States)

    Percival, J. A.

    1986-01-01

    The Quetico Belt lies between the metavolcanic Wawa-Shebandowan and Wabigoon Belts. It consists of marginal metasedimentary rocks and central pelitic, gneissic and plutonic rocks. Metamorphism is Barrovian, at depths less than 10 km, and grade increases from margins to core of the belt: the outermost pelites are at chlorite-muscovite grade; inward a garnet-andalusite zone formed throughout the inner margin; and the central zone ranges form garnet-andalusite in the west and garnet-sillimanite-muscovite to garnet-sillimanite-cordierite and rare kyanite 6 to 150 km to the east. This increase is correlated with granitic intrusives. Migmatites in the core have intrusive leucosomes in the west and locally derived ones in the east. Isograd surfaces are steep where the belt is narrow and dip gently where it is wide. The Quetico Park intrusive complex of the central region of the Quetico Belt shows a zonation across it 20 to 50 km width from older, medium grained biotite composition to younger, coarse to pegmatitic granitic composition. Sediment of the Quetico basin had its source in the bordering metavolcanic belts and was deposited ca. 2.75 to 2.70 Ga ago. Boundaries of the belt dip inward, so it essentially is a graben of inter-arc or back-arc type.

  12. Diversity of Dicotyledenous-Infecting Geminiviruses and Their Associated DNA Molecules in Southern Africa, Including the South-West Indian Ocean Islands

    Directory of Open Access Journals (Sweden)

    Lindy L. Esterhuizen

    2012-09-01

    Full Text Available The family Geminiviridae comprises a group of plant-infecting circular ssDNA viruses that severely constrain agricultural production throughout the temperate regions of the world, and are a particularly serious threat to food security in sub-Saharan Africa. While geminiviruses exhibit considerable diversity in terms of their nucleotide sequences, genome structures, host ranges and insect vectors, the best characterised and economically most important of these viruses are those in the genus Begomovirus. Whereas begomoviruses are generally considered to be either monopartite (one ssDNA component or bipartite (two circular ssDNA components called DNA-A and DNA-B, many apparently monopartite begomoviruses are associated with additional subviral ssDNA satellite components, called alpha- (DNA-as or betasatellites (DNA-βs. Additionally, subgenomic molecules, also known as defective interfering (DIs DNAs that are usually derived from the parent helper virus through deletions of parts of its genome, are also associated with bipartite and monopartite begomoviruses. The past three decades have witnessed the emergence and diversification of various new begomoviral species and associated DI DNAs, in southern Africa, East Africa, and proximal Indian Ocean islands, which today threaten important vegetable and commercial crops such as, tobacco, cassava, tomato, sweet potato, and beans. This review aims to describe what is known about these viruses and their impacts on sustainable production in this sensitive region of the world.

  13. Deep-water bivalve mollusks collected during the TALUD XV cruise off the west coast of the southern Baja California Peninsula, Mexico

    Science.gov (United States)

    Valentich-Scott, Paul; Suárez-Mozo, Nancy Yolimar

    2016-01-01

    Abstract Background During the TALUD XV research cruise off the southern part of the Baja California Peninsula, Mexico, samples of macro-invertebrates obtained in the deep-sea (296–2136 m) revealed a rich fauna of bivalves (17 species belonging to 10 families). The number of species per station varied from one to five. The richest families were Nuculidae, Nuculanidae, Neilonellidae, Limidae, and Cuspidariidae. Solemyidae, Lucinidae, Poromyidae, Verticordiidae, and Pectinidae were each represented by a single species. Some species groups need a thorough revision and were tentatively identified (Nuculana cf. hamata, Limatula cf. saturna). New information Significant new distribution information is provided for two species, both recorded for the first time from off western Mexico: Ennucula panamina with an extension of its known distribution over 20° of latitude north and Jupiteria callimene with an extension of 16° 42' of latitude to the north. One species (Ennucula taeniolata) is reported in shallower depth and one in deeper water (Acesta sphoni). New records are provided for an additional nine species. Environmental and habitat conditions are given for the first time for many of the bivalve species. PMID:27346956

  14. Seawater-like trace element signatures (REE + Y) of Eoarchaean chemical sedimentary rocks from southern West Greenland, and their corruption during high-grade metamorphism

    Science.gov (United States)

    Friend, C. R. L.; Nutman, A. P.; Bennett, V. C.; Norman, M. D.

    2008-02-01

    Modern chemical sediments display a distinctive rare earth element + yttrium (REE + Y) pattern involving depleted LREE, positive La/La*SN, Eu/Eu*SN, and YSN anomalies (SN = shale normalised) that is related to precipitation from circumneutral to high pH waters with solution complexation of the REEs dominated by carbonate ions. This is often interpreted as reflecting precipitation from surface waters (usually marine). The oldest broadly accepted chemical sediments are c. 3,700 Ma amphibolite facies banded iron-formation (BIF) units in the Isua supracrustal belt, Greenland. Isua BIFs, including the BIF international reference material IF-G are generally considered to be seawater precipitates, and display these REE + Y patterns (Bolhar et al. in Earth Planet Sci Lett 222:43 60, 2004). Greenland Eoarchaean BIF metamorphosed up to granulite facies from several localities in the vicinity of Akilia (island), display REE + Y patterns identical to Isua BIF, consistent with an origin by chemical sedimentation from seawater and a paucity of clastic input. Furthermore, the much-debated magnetite-bearing siliceous unit of “earliest life” rocks (sample G91/26) from Akilia has the same REE + Y pattern. This suggests that sample G91/26 is also a chemical sediment, contrary to previous assertions (Bolhar et al. in Earth Planet Sci Lett 222:43 60, 2004), and including suggestions that the Akilia unit containing G91/26 consists entirely of silica-penetrated, metasomatised, mafic rock (Fedo and Whitehouse 2002a). Integration of our trace element data with those of Bolhar et al. (Earth Planet Sci Lett 222:43 60, 2004) demonstrates that Eoarchaean siliceous rocks in Greenland, with ages from 3.6 to 3.85 Ga, have diverse trace element signatures. There are now geographically-dispersed, widespread examples with Isua BIF-like REE + Y signatures, that are interpreted as chemically unaltered, albeit metamorphosed, chemical sediments. Other samples retain remnants of LREE depletion but

  15. Geography of the asteroid belt

    Science.gov (United States)

    Zellner, B. H.

    1978-01-01

    The CSM classification serves as the starting point on the geography of the asteroid belt. Raw data on asteroid types are corrected for observational biases (against dark objects, for instance) to derive the distribution of types throughout the belt. Recent work on family members indicates that dynamical families have a true physical relationship, presumably indicating common origin in the breakup of a parent asteroid.

  16. Pathogenicity of two recent Western Mediterranean West Nile virus isolates in a wild bird species indigenous to Southern Europe: the red-legged partridge

    Directory of Open Access Journals (Sweden)

    Sotelo Elena

    2011-01-01

    Full Text Available Abstract West Nile virus (WNV is an emerging zoonotic pathogen whose geographic spread and incidence in humans, horses and birds has increased significantly in recent years. WNV has long been considered a mild pathogen causing self-limiting outbreaks. This notion has changed as WNV is causing large epidemics with a high impact on human and animal health. This has been particularly noteworthy since its introduction into North America in 1999. There, native bird species have been shown to be highly susceptible to WNV infection and disease with high mortalities. For this reason, the effect of WNV infection in North American bird species has been thoroughly studied by means of experimental inoculations in controlled trials. To a lesser extent, European wild birds have been shown to be affected clinically by WNV infection. Yet experimental studies on European wild bird species are lacking. The red-legged partridge (Alectoris rufa is a gallinaceous bird indigenous to the Iberian Peninsula, widely distributed in South Western Europe. It plays a key role in the Mediterranean ecosystem and constitutes an economically important game species. As such it is raised intensively in outdoor facilities. In this work, red-legged partridges were experimentally infected with two recent WNV isolates from the Western Mediterranean area: Morocco/2003 and Spain/2007. All inoculated birds became viremic and showed clinical disease, with mortality rates of 70% and 30%, respectively. These results show that Western Mediterranean WNV variants can be pathogenic for some European bird species, such as the red-legged partridge.

  17. Cenozoic crustal shortening and thickening contributions to Andean orogenesis: Preliminary results from structural mapping in the southern Peruvian Andes

    Science.gov (United States)

    Perez, N.; Horton, B. K.

    2012-12-01

    Estimates of Cenozoic crustal shortening and thickening from the southern Peruvian Andes are necessary to address ongoing debates regarding growth of the Andes and Altiplano plateau. However, limited regional studies in southern Peru prevent accurate assessments of the structural contributions to high topography. This study provides new structural mapping along a >200 km transect spanning the northernmost Altiplano to Subandes at 13-15.5°S and fills the gap between existing central Peruvian and northern Bolivian studies. New stratigraphic data, fault relationships and fold orientations are used to create an updated geologic map and provide insights into the style, timing and magnitude of crustal deformation. Preliminary cross sections accompanying these map transects illustrate deformation style and provide first-order estimates of shortening. Further cross section analyses will be balanced and provide estimates of total crustal shortening and associated thickening in southern Peru. The study transect is subdivided into belts according to the age of exposed rocks and style of deformation. From west to east these belts include: Cretaceous strata dominated by tight folds, closely spaced faults and multiple detachments; Permo-Triassic strata dominated by thicker thrust sheets and fault-fold orientations departing from typical Andean trends; and Paleozoic rocks characterized by thick thrust sheets and deformation focused near major faults. The Cretaceous belt is composed of marine limestones and upward coarsening, siltstone to coarse sandstone progradational sequences. Disharmonic and detachment folds in the Cretaceous section demonstrate the importance of interbedded gypsum and mudstone layers. Fault relationships suggest local shortening during the Early Cretaceous. The Permo-Triassic belt is composed of thick Permian carbonates (Copacabana Formation) and interbedded sandstones, conglomerates and volcanics of the Mitu Formation. This study defines the orientation of

  18. Tourmaline and Rutile as Indicators of a Magmatic-hydrothermal Origin for Tourmalinite Layers in the São José do Barreiro Area, NE Ribeira Belt, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Gianna Maria Garda

    2010-10-01

    Full Text Available Tourmalines from tourmaline-rich layers intercalated with schists of the Rio Una Unit of the Embu Complex and fromcoarse-grained tourmalinite layers associated with quartzite from São José do Barreiro and Formoso (Central Ribeira Belt,São Paulo State, Brazil were analyzed for major, trace- and rare-earth elements and boron stable isotopes. Two main phasesof tourmaline formation were identified by mineral chemistry. The tourmalines from the schist-hosted tourmaline layers arecharacterized by relatively low MgO (from 4.7 to 6.5%, Na2O (1.5 to 2.1% and CaO (from 0.2 to 1.1% contents andhigh Al2O3 (from 32 to 35% and FeO (from 6.7 to 9.0% contents, and also by two (REECN patterns, one represented by(La/YbCN from 2.7 to 4.3 and positive Eu anomalies, and the other by (La/YbCN from 0.2 to 0.3 and practically no Euanomaly. The variations in major-element contents reflect the composition of the rock being metamorphosed and in whichtourmaline is crystallizing, whereas the (REECN patterns indicate the evolution of the metamorphic fluid in face of changingmetamorphic conditions. The tourmaline of the tourmalinite layers intercalated in quartzite is characterized by relatively highAl2O3 (from 32.3 to 33.92%, FeO (from 6.54 to 7.3% and Na2O (from 1.8 to 2.1% contents and very low total REE (3.5ppm contents, in particular of HREE. The (REECN pattern for this tourmaline is characterized by a positive Eu anomaly,indicating a high fluid/rock ratio. The δ11B values for this tourmaline fall in the -12.3 and -13.9‰ interval. On the other hand,the tourmaline of a massive tourmalinite also associated with quartzite has the highest MgO (from 7.3 to 9.7%, CaO (from0.8 to 2.5%, F, Th, U, Hf, Zr, Y, Sr and total REE (305 ppm contents and the lowest Al2O3 (from 28.6 to 31.8% and FeO(from 5.4 to 8.3% contents, when compared to the other tourmalines analyzed. Differing from all other (REECN patterns,the one that characterizes this tourmaline is LREE-enriched [(La

  19. Magnetotelluric array data analysis from north-west Fennoscandia

    Science.gov (United States)

    Cherevatova, M.; Smirnov, M. Yu.; Jones, A. G.; Pedersen, L. B.; Becken, M.; Biolik, M.; Cherevatova, M.; Ebbing, J.; Gradmann, S.; Gurk, M.; Hübert, J.; Jones, A. G.; Junge, A.; Kamm, J.; Korja, T.; Lahti, I.; Löwer, A.; Nittinger, C.; Pedersen, L. B.; Savvaidis, A.; Smirnov, M.

    2015-06-01

    New magnetotelluric (MT) data in north-west Fennoscandia were acquired within the framework of the project "Magnetotellurics in the Scandes" (MaSca). The project focuses on the investigation of the crustal and upper mantle lithospheric structure in the transition zone from stable Precambrian cratonic interior to passive continental margin beneath the Caledonian orogen and the Scandinavian Mountains in western Fennoscandia. An array of 59 synchronous long period and 220 broad-band MT sites was occupied in the summers of 2011 to 2013. We estimated MT transfer functions in the period range from 0.003 to 105 s. The Q-function multi-site multi-frequency analysis and the phase tensor were used to estimate strike and dimensionality of MT data. Dimensionality and strike analyses indicate generally 2-D behaviour of the data with 3-D effects at some sites and period bands. In this paper we present 2-D inversion of the data, 3-D inversion models are shown in the parallel paper. We choose to invert the determinant of the impedance tensor to mitigate 3-D effects in the data on our 2-D models. Seven crustal-scale and four lithospheric-scale 2-D models are presented. The resistive regions are images of the Archaean and Proterozoic basement in the east and thin Caledonian nappes in the west. The middle and lower crust of the Svecofennian province is conductive. The southern end of the Kittilä Greenstone Belt is seen in the models as a strong upper to middle crustal conductor. In the Caledonides, the highly conductive alum shales are observed along the Caledonian Thrust Front. The thickest lithosphere is in the Palaeoproterozioc Svecofennian Domain, not in the Archaean. The thickness of the lithosphere is around 200 km in the north and 300 km in the south-west.

  20. Maintain and control of vaccination belt along neighbouring rabies infected area

    Directory of Open Access Journals (Sweden)

    Hostnik P.

    2012-01-01

    Full Text Available The programme of oral vaccination of wildlife started in 1988 in Slovenia and is based on our and the experiences of other countries. Red foxes are the main reservoir of rabies in Slovenia. When the oral vaccination programme started in whole territory of Slovenia in the year 1995, 1089 (28.75% of tested animals were detected positive among wild and domestic animals. Four years later only 6 (0.5% positive cases were detected among 1195 tested animals. The number of positive cases been increased again in 2001 to 135 cases. Between 2002 and 2008 the vaccination was done only in the protection zone, a 30 to 50 km wide belt along the southern border with Croatia because no new rabies cases were found in the north-west region of the country. When rabies was reintroduced in Italy in 2008 the vaccination was carried out again in the whole territory of Slovenia. In order to improve the vaccination campaign the stability of two vaccines was measured over 8 weeks. In both vaccines the drop of the virus titre was the highest when baits were placed in the sunlight, but, in the shadow, the virus was detected until day 53 of observation. The aim of this study is to summarise the current status of rabies and to look for the best solutions in the next vaccination campaign.

  1. Evaluation of the static belt fit provided by belt-positioning booster seats.

    Science.gov (United States)

    Reed, Matthew P; Ebert, Sheila M; Sherwood, Christopher P; Klinich, Kathleen D; Manary, Miriam A

    2009-05-01

    Belt-positioning booster seats are recommended for children who use vehicle seat belts as primary restraints but who are too small to obtain good belt fit. Previous research has shown that belt-positioning boosters reduce injury risk, but the belt fit produced by the wide range of boosters in the US market has not previously been assessed. The present study describes the development of a method for quantifying static belt fit with a Hybrid-III 6-year-old test dummy. The measurement method was applied in a laboratory seat mockup to 31 boosters (10 in both backless and highback modes) across a range of belt geometries obtained from in-vehicle measurements. Belt fit varied widely across boosters. Backless boosters generally produced better lap belt fit than highback boosters, largely because adding the back component moved the dummy forward with respect to the lap belt routing guides. However, highback boosters produced more consistent shoulder belt fit because of the presence of belt routing guides near the shoulder. Some boosters performed well on both lap belt and shoulder belt fit. Lap belt fit in dedicated boosters was generally better than in combination restraints that also can be used with an integrated harness. Results demonstrate that certain booster design features produce better belt fit across a wide range of belt geometries. Lap belt guides that hold the belt down, rather than up, and shoulder belt guides integrated into the booster backrest provided better belt fit. PMID:19393812

  2. Chaos on the conveyor belt

    CERN Document Server

    Sándor, Bulcsú; Tél, Tamás; Néda, Zoltán

    2013-01-01

    The dynamics of a spring-block train placed on a moving conveyor belt is investigated both by simple experiments and computer simulations. The first block is connected by spring to an external static point, and due to the dragging effect of the belt the blocks undergo complex stick-slip dynamics. A qualitative agreement with the experimental results can only be achieved by taking into account the spatial inhomogeneity of the friction force on the belt's surface, modeled as noise. As a function of the velocity of the conveyor belt and the noise strength, the system exhibits complex, self-organized critical, sometimes chaotic dynamics and phase transition-like behavior. Noise induced chaos and intermittency is also observed. Simulations suggest that the maximum complexity of the dynamical states is achieved for a relatively small number of blocks, around five.

  3. Tectonics of the Tongbai-Dabie fold belt

    Science.gov (United States)

    Wenpu, Ma

    The Qinling fold belt is the northernmost branch of the Paleozoic and Mesozoic Tethys in eastern Asia and contains all the inter-reacting records of the North China Block (NCB) and the South China Block (SCB). The Tongbai-Dabie fold belt is its eastern section. The Qinling belt was a collage of two orogens. The north Qinling is a late Paleozoic collision orogen, which started with Proterozoic rifting, transforming into active continental margin during the middle Ordovician. The intermitten ophiolite fragments indicate the existence of an oceanic crust at that time. The collision that occurred in the Devonian was an east-west diachronous process. The main suture zone is marked by ophiolitic melange extending nearly 500 km. The late Mesozoic molasse, volcano-plutonic activity and huge imbricate thrust system all respond to the further shortening of the crust and adjustment of the intracontinental strain. The south Qinling east of the Nanyang Basin is located to the south of Tongbai mountain. A pile of thick Sinian-Silurian volcanic and marine clastic deposits imply another marine incursion. Its history in south Shaanxi could continue to the Mesozoic. The flysch trough represented by Xinyang group may be the key area for revealing the relationship between north and south Qinling. The discussion in the paper is mainly focused on the nature and evolution of the Tongbai-Dabie fold belt.

  4. Structural appraisal of the Gadag schist belt from gravity investigations

    Indian Academy of Sciences (India)

    G Ramadass; D Himabindu; N Srinivasulu

    2003-12-01

    Semi-detailed gravity investigations were carried out over an area of approximately 2750 sq km with maximum N-S and E-W extents of 55 and 50km respectively in the Gadag region in the Dharwar craton with a view to obtain a clearer perception of the structural configuration of the region. From qualitative analysis of the gravity data, several tectonic features are inferred: the high density Gadag schist belt is characterized by a gravity high and occurs in two discontinuous segments — the main N-S trending segment, and its thinner NW-SE trending extension, the two separated by a NE-SW trending deep seated fault. While the N-S trend of the Gadag schist belt is bounded on its east by the NW-SE trending Chitradurga thrust fault and on its west by another major NNW-SSE trending fault, the NW-SE extension is likewise bounded by two other NW-SE major faults. Quantitative evaluation from forward modeling/inversion of five profiles in the region, assuming a density contrast of 0.29 gm/cc of the anomalous schistose body with the gneissic host rocks indicated a synclinal structure plunging to the southeast along its axis for the Gadag schist belt. The maximum width and depth from surface of the schist belt are 22km and 5.6km respectively.

  5. Neoproterozoic geodynamic evolution of SW-Gondwana: a southern African perspective

    Science.gov (United States)

    Frimmel, H. E.; Basei, M. S.; Gaucher, C.

    2011-04-01

    Our current understanding of the tectonic history of the principal Pan-African orogenic belts in southwestern Africa, reaching from the West Congo Belt in the north to the Lufilian/Zambezi, Kaoko, Damara, Gariep and finally the Saldania Belt in the south, is briefly summarized. On that basis, possible links with tectono-stratigraphic units and major structures on the eastern side of the Río de la Plata Craton are suggested, and a revised geodynamic model for the amalgamation of SW-Gondwana is proposed. The Río de la Plata and Kalahari Cratons are considered to have become juxtaposed already by the end of the Mesoproterozoic. Early Neoproterozoic rifting led to the fragmentation of the northwestern (in today's coordinates) Kalahari Craton and the splitting off of several small cratonic blocks. The largest of these ex-Kalahari cratonic fragments is probably the Angola Block. Smaller fragments include the Luis Alves and Curitiba microplates in eastern Brazil, several basement inliers within the Damara Belt, and an elongate fragment off the western margin, named Arachania. The main suture between the Kalahari and the Congo-São Francisco Cratons is suspected to be hidden beneath younger cover between the West Congo Belt and the Lufilian/Zambezi Belts and probably continues westwards via the Cabo Frío Terrane into the Goiás magmatic arc along the Brasilia Belt. Many of the rift grabens that separated the various former Kalahari cratonic fragments did not evolve into oceanic basins, such as the Northern Nosib Rift in the Damara Belt and the Gariep rift basin. Following latest Cryogenian/early Ediacaran closure of the Brazilides Ocean between the Río de la Plata Craton and the westernmost fragment of the Kalahari Craton, the latter, Arachania, became the locus of a more than 1,000-km-long continental magmatic arc, the Cuchilla Dionisio-Pelotas Arc. A correspondingly long back-arc basin (Marmora Basin) on the eastern flank of that arc is recognized, remnants of which

  6. Estimation of the shortening rate since late Pleistocene in the Aksu area on the southern flank of the Tianshan, China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This research focused on the Aksu area in the central part of the southern Tianshan. Along the 60 km wide Aksu fold-and-thrust belt, active thrusts reach the surface and offset the youngest sediments. Our research was based on the geomorphologic study that examined the advance and retreat of glaciers cut by thrusts in the Tomur area in the north of Aksu. Our fieldwork revealed that two fault scarps were clearest across three different moraines that represent the maximum of advance of glaciers during three glacial periods along the Tailan River in the Tomur area. The measured heights of the fault scarps that cut the moraines, together with the moraines-inferred age, imply a shortening rate of 1.85 mm/a on the Aksu area since late Pleistocene. This rate, similar to that of the Korla area on its east side and of the Kaping area on its west side, but lower than that of the Kashgar area farther west and of the Manas area in the northern margin of the belt, implies that the distribution of shortening across the Tianshan changed markedly along the mountain.

  7. Geological setting and tectonic subdivision of the Neoproterozoic orogenic belt of Tuludimtu, western Ethiopia

    Science.gov (United States)

    Allen, Alistair; Tadesse, Gebremedhin

    2003-05-01

    The N-S trending Tuludimtu Belt in the extreme west of Ethiopia has been subdivided into five lithotectonic domains, from east to west, the Didesa, Kemashi, Dengi, Sirkole and Daka domains. The Kemashi, Dengi and Sirkole Domains, forming the core of the belt, contain volcano-sedimentary successions, whilst the Didesa and Daka Domains are gneiss terranes, interpreted to represent the eastern and western forelands of the Tuludimtu Belt. The Kemashi Domain, which consists of an ophiolitic sequence of ultramafic and mafic volcanic and plutonic rocks together with sedimentary rocks of oceanic affinity, is interpreted as oceanic crust and is considered to represent an arc-continent suture zone. The Dengi Domain, composed of mafic to felsic volcanic and plutonic rocks, and a sequence of volcanoclastic, volcanogenic, and carbonate sediments, is interpreted as a volcanic arc. The Sirkole Domain consists of alternating gneiss and volcano-sedimentary sequences, interpreted as an imbricated basement-cover thrust-nappe complex. All the domains are intruded by syn- and post-kinematic Neoproterozoic granitoids. Structural analysis within the Didesa and Daka Domains indicate the presence of pre-Pan African structures, upon which Neoproterozoic deformation has been superimposed. The gneissic rocks of these two domains are regarded as pre-Pan African continental fragments amalgamated to West Gondwana during Neoproterozoic collision events. Unconformably overlying all of the above are a series of tilted but internally undeformed conglomerate-sandstone-shale sequences, regarded as post-accretionary molasse-type deposits, formed during gravitational collapse of the Tuludimtu Belt. The Tuludimtu Belt is interpreted as a collision orogenic belt formed during the assembly of West Gondwana prior to final closure of the Mozambique Ocean.

  8. Notes on Southern African Tuberales

    Directory of Open Access Journals (Sweden)

    W. F. O. Marasas

    1973-09-01

    Full Text Available Three species of Tuberales have been found in Southern Africa.  Terfezia pfeilii Henn. occurs in the Kalahari Desert and adjacent areas of the Cape Province, Botswana and South-West Africa. The other two,  Terfezia austroafricana sp. nov. and  Choiromyces echinulatus sp. nov., are known only from the Cape.  C. echinulatus is the first representative of that genus to be collected in Africa or the Southern Hemisphere.

  9. Neurocisticercose em pacientes internados por epilepsia no Hospital Regional de Chapecó região oeste do Estado de Santa Catarina Prevalence of neurocysticercosis among epileptic in-patients in the west of Santa Catarina - Southern Brazil

    Directory of Open Access Journals (Sweden)

    PAULO CESAR TREVISOL-BITTENCOURT

    1998-03-01

    evaluate NC as aetiology of epilepsy in the west of Santa Catarina. This state belong to southern Brazil and it has a very developed economy. However, due the widespread swine farming in the west district, many of them without any sanitary control, the national health authorities have considered all this area at risk to NC. The study was carried out in Chapecó, the main town in that region, where CT Scan service was started in 1995. All patients put on hospital care due epileptic seizures in 1995-96 were considered. Febrile convulsions were excluded of the sample. We found a very expressive prevalence rate of NC among patients suffering from epilepsy. Roughly 24% of these patients, showed unequivocal tomography evidences for the diagnosis of NC. Our data suggest cysticercosis as a real endemic trouble in the area and, overdosis of information in proper language, diffuse to the whole population, seems to be the only remedy to fight against it. Moreover, we should pay special attention to everyone related to swine farming, does not matter how this activity has been classificated.

  10. Launching jets from accretion belts

    CERN Document Server

    Schreier, Ron

    2016-01-01

    We propose that sub-Keplerian accretion belts around stars might launch jets. The sub-Keplerian inflow does not form a rotationally supported accretion disk, but it rather reaches the accreting object from a wide solid angle. The basic ingredients of the flow are a turbulent region where the accretion belt interacts with the accreting object via a shear layer, and two avoidance regions on the poles where the accretion rate is very low. A dynamo that is developed in the shear layer amplifies magnetic fields to high values. It is likely that the amplified magnetic fields form polar outflows from the avoidance regions. Our speculative belt-launched jets model has implications to a rich variety of astrophysical objects, from the removal of common envelopes to the explosion of core collapse supernovae by jittering jets.

  11. Kuiper Belts Around Nearby Stars

    CERN Document Server

    Nilsson, R; Brandeker, A; Olofsson, G; Pilbratt, G L; Risacher, C; Rodmann, J; Augereau, J -C; Bergman, P; Eiroa, C; Fridlund, M; Thébault, P; White, G J

    2010-01-01

    In order to detect and characterise cold extended circumstellar dust originating from collisions of planetesimal bodies in disks, belts, or rings at Kuiper-Belt distances (30--50\\,AU or beyond) sensitive submillimetre observations are essential. Measurements of the flux densities at these wavelengths will extend existing IR photometry and permit more detailed modelling of the Rayleigh-Jeans tail of the disks spectral energy distribution (SED), effectively constraining dust properties and disk extensions. By observing stars spanning from a few up to several hundred Myr, the evolution of debris disks during crucial phases of planet formation can be studied. // We have performed 870\\,$\\mu$m observations of 22 exo-Kuiper-Belt candidates, as part of a Large Programme with the LABOCA bolometer at the APEX telescope. Dust masses (or upper limits) were calculated from integrated 870\\,$\\mu$m fluxes, and fits to the SED of detected sources revealed the fractional dust luminosities $f_{\\mathrm{dust}}$, dust temperatures...

  12. Morphotectonics of the Southern Puerto Rico Offshore Margin

    Science.gov (United States)

    Granja Bruna, J.; Carbó-Gorosabel, A.; Llanes Estrada, P.; Ten Brink, U. S.; Munoz Martin, A.; Fuertes Ortega, R.; Druet, M.; Gómez, M.; Martin Davila, J. M.; Pazos, A.; Catalan, M.

    2012-12-01

    The southern insular slope of Puerto Rico is characterized by active tectonics, sedimentary and slope failure processes related to the southward thrusting of the island arc over the Caribbean plate's interior. The east-west trending Muertos fold-and-thrust belt and the Investigator fault zone are the main structural and morphological features along the insular slope. It was suggested that these tectonic features accommodate a highly oblique motion between the Caribbean plate's interior and the North American plate. New systematic multibeam bathymetry data and seismic reflection profiles have allowed us to improve the knowledge of the complex morphologic and structural fabric of this zone of active deformation. We divided the region into morphotectonic slope provinces on the basis of morphological, structural and sedimentological criteria. The lower slope province is occupied by the east-west trending Muertos fold-and-thrust belt. Seismic data image pelagic, hemipelagic and turbiditic sediments of the Venezuelan basin and Muertos Trough basin being partially offscraped and accreted forming a sequence of numerous imbricate thrust slices verging southwards. The surface expression of the imbricate structure is a highly steeped slope characterized by an alternation of narrow troughs and elongate anticline ridges oriented sub-parallel to the deformation front. The upper slope province is occupied by the Investigator fault zone, a broad zone of deformation composed of two straight strands that form narrow E-W trending valleys in the insular slope. Submarine canyons carve through the narrow E-W trending valleys or terminate in them but show no evidence for lateral offsets, indicating an absence of recent strike-slip motion. The seafloor expression of the Investigator fault zone suggests a sub-vertical fault plane accommodating a small amount of N-S extension. This fault zone terminates eastward in Whiting basin and disappears westwards beneath the thick slope deposits on a

  13. Oakland, West

    OpenAIRE

    Kwamille, Tasion Shawniece

    2013-01-01

    “Oakland, West” Produced by: Tasion Kwamilele          After World War II, many blacks from the south migrated to Oakland to work in the shipyards; housing discrimination forced blacks to move to West Oakland. But when those jobs died out many Blacks moved from West Oakland and the area became deserted and filled with crime, drugs, violence, and poverty.         The 7.0 Loma Prueta Earthquake, also known as the World Series Quake of 1989, shook the Bay Are...

  14. Tectonic entities connection between West Junggar (NW China) and East Kazakhstan

    Science.gov (United States)

    Zhao, Lei; He, Guoqi

    2013-08-01

    West Junggar (NW China) and East Kazakhstan are situated in the southwest of the Central Asian orogenic belt (CAOB). Tectonic entities in the two areas share the same tectonic evolution history and make up the famous horseshoe-shaped orocline in Central Asia. This paper presents a newly compiled cross-border tectonic sketch map of West Junggar and East Kazakhstan and proposes the extension of the Chingiz-Tarbagatai belt and the North Balkhash-West Junggar belt. The Chingiz-Tarbagatai Belt in East Kazakhstan consists mainly of Middle-Late Ordovician differentiated volcanic rocks, pyroclastic sediments and flysch; while in the Tarbagatai Mountain in China, Tarbagatai (Kujibai) ophiolite is newly found with zircon (gabbro) age of 478 ± 3 Ma and the Ordovician flysch metamorphosed to a greenschist facies is distinguished from Devonian-Carboniferous rock associations. Therefore, the Early Paleozoic Chingiz-Tarbagatai belt of East Kazakhstan evidently extends to the northern part of West Junggar along the Tarbagatai orogenic belt. The North Balkhash-West Junggar belt lying south to the Chingiz-Tarbagatai belt is separated by the EW-trending Baiyanghe-Heshituoluogai depression in West Junggar. Early Ordovician-Early Silurian ophiolitic fragments and related pyroclastic sediments are widely exposed in Tekturmas, North Balkhash and Agadyr of East Kazashtan. Similarly, Early Paleozoic ophiolites have also been verified in Tangbale, Mayile, Baerluke, Darbut and Karamay of West Junggar in recent years. Therefore, nearly all ophiolites in West Junggar and East Kazakhstan are proved to have formed in Early Paleozoic, which suggests that the evolution of the paleo-ocean in the two areas reached its peak in the Early Paleozoic. Based on the ages of the Tangbale, Karamay and Hongguleleng ophiolites, an Early Paleozoic continental accretionary belt extending from Tangbale to Hongguleleng is determined at the NW margin of the Junggar basin for the first time. According to

  15. Study of thermal conditions at belt slippage

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, R.; Pampel, W.; Pfleger, P.

    1987-04-01

    Conveyor belt slippage experiments are carried out on the Chrudim (Czechoslovakia) industrial sized test stand for belt widths up to 1 m and driving drum forces up to 400 kW. The stand is operated jointly by TAKRAF (GDR) and VITKOVICE VUTZ, Prague. From 1972 to 1981, 7 belt conveyor fires occurred in GDR brown coal surface mines due to belt slippage. One of these cases led to a belt fire after only 15 s at 100% belt slippage. Aim of the study was to determine accurate permissible slippage values. Design of the test stand is explained as well as test procedures with belt slippage at the driving drum varying between 10 and 100%. Belt driving parameters were measured along with temperature of the drum surface. The heat penetration parameter b (in kJ/m/sup 2/) was calculated. Maximum temperatures up to 150 C were measured on the drum during partial slippage and 370 C at 100% belt slippage. The ignition temperature of rubber abrasion fines was also analyzed and found to vary between 40 and 318 C, i.e. substantially lower than belt and drum layer ignition temperatures. Graphs and diagram of slippage measurement results are calculated. Values for permissible maximum slippage time for operating belt slippage monitoring devices are shown. These devices are required to be installed in the GDR at heavy mine belt conveyors with driving forces exceeding 500 kW. 8 refs.

  16. French experience in seat belt use.

    NARCIS (Netherlands)

    Lassarre, S. & Page, Y.

    1992-01-01

    This paper concerns the French experience in seat belt use. As well as the seat belt regulations, the strategies employed to reinforce the wearing of seat belts by using information and encouragement campaigns and checks by the police and gendarmerie are described here along with their timetables an

  17. Canonical Correlation Factors Causing the Formation of Accumulated Sand-belts along the Oasis Fringe in Hexi Corridor

    Institute of Scientific and Technical Information of China (English)

    Chang; Zhaofeng; Wang; Qiangqiang; Zhang; Jianhui; Tang; Jinnian; Zhu; Shujuan; Fan; Baoli; Zhang; Dabiao; Liu; Shizeng; Zhang; Guozhong; Li; Aide

    2014-01-01

    Accumulated sand-belts refer to those formed along the oasis fringe,especially at the upwind location,due to the accumulation of sand blocked by farmland windbreak. In the 60 years since the foundation of new China,a lot of trees have been planted for desertification combating in northwest and north China,thus,accumulated sand-belts were formed at the upwind location. The formation and the ecological effects of the accumulated sand-belts along the oasis fringe is a new scientific concern. To study the formation causes of these belts in Hexi corridor,21 samples were selected,and the height / width of the belts,as well as the vegetation,soil,soil moisture and climatic factors were investigated. This paper analyzed the correlation between the height / width of the belts and the vegetation,soil,soil moisture and climatic factors using the methods of variance analysis,correlation analysis and canonical correlation analysis. The results indicate that: the accumulated sand-belts take a trend of being high and wide in the east whereas low and narrow in the west,and most of the parts tend to be stable; the species on the belts are dominated by Tamarix austromongolica,the vegetation cover and the pure vegetation cover of different dominant species on the leeward slope of the accumulated sand-belts vary significantly. The canonical correlation analysis shows that: the height and width of accumulated sand-belt is the interaction of precipitation,distance to the sand source,leeward vegetation cover and annual average wind speed. Moreover,the height of accumulated sand-belts are negatively correlated to the soil moisture at the depth of 30- 50 cm,air humidity and leeward vegetation cover,and the width of the belts is also negatively correlated with the distance to the sand source. The ecological effects of the accumulated sand-belts are both positive( stopping sands from moving into farmland,protective role as an obstacle)and negative( when the belts decay and activate one day

  18. The constraints of strain partitioning and geochronology in Luonan-Luanchuan tectonic belts on Qinling orogenic belt

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Luonan-Luanchuan tectonic belt lies between the North China Block and Qinling Mountains, in- cluding the Luonan-Luanchuan fault zone and the strong deformation zone to the north of the fault. The ductile shear zone, imbricate brittle fault and duplex structure in the fault zone now are the expression of the same tectonic event in different depth. Such lineation structure exists in the tectonic belts as mineral lineation, elongation lineation, crenulation lineation, sheath folds and so on, indicating NE-directed plate motion. Fold axes and thrusts in the strong deformation zone are inclined to the Luonan-Luanchuan fault zone at small angles. The structures with different natures show a regular pattern, produced during oblique convergence of plates. The convergence factors are as follows:The direction of plate convergence is 22°, 31° and the angle between the plate convergence direction and plate boundary is 73°, 82° respectively in the west and east segment. The Luonan-Luanchuan tectonic belt was deformed strongly in 372 Ma, resulted from Erlangping back-arc ocean basin subduction sin- istrally and obliquely to North China Block during the collision of North China Block and South China Block.

  19. Discussion on regional geo tectonic setting of Ganhang tectonic belt

    International Nuclear Information System (INIS)

    The knowledge of Precambrian structural framework in southern China has been progressed during a long period of study. Based on the comprehensive analysis on Precambrian formations and tectonic evolution the following conclusions are made: (1) The Cathaysia is a desintegrated Early Precambrian old land; (2) Zhexi-Gandongbei region was an active continental margin; (3) The Wuling orogeny is the most important one in the evolution of southern China during which a collision between the Cathaysia and Yangzi blocks occurred forming the united South China Old-land; (4) The Late Proterozoic tectonic evolution in various areas showed obvious difference because of the difference in regional geology. In a word, the Ganhang fault belt was an 'A' subduction zone in the early stage of Late Proterozoic

  20. Tectonic affinity of the Alxa Block, Northwest China: Constrained by detrital zircon U-Pb ages from the early Paleozoic strata on its southern and eastern margins

    Science.gov (United States)

    Zhang, Beihang; Zhang, Jin; Zhang, Yiping; Zhao, Heng; Wang, Yannan; Nie, Fengjun

    2016-06-01

    The tectonic affinity of the Alxa Block is important in the reconstruction of the paleogeographical evolution of China. The early Paleozoic strata (the Dahuangshan Formation and Xiangshan Group) of the southern and eastern Alxa Block have consistent rock compositions, similar depositional ages, paleocurrents, detrital zircon age distributions, and cumulative probability curves of crystallization ages for detrital zircon grains relative to the depositional ages, and were deposited in similar slope basins. All these data indicate that the early Paleozoic strata of the Alxa Block were sourced predominantly from Neoproterozoic orogenic belts in the eastern Gondwana continent, instead of the Alxa Block to the north, the North China Block to the east and the North Qilian Orogenic Belt to the south. During the early Paleozoic, the Alxa Block was an independent block with the South China Block (SCB) to the west and the North China Block (NCB) to the east and situated to the northwest of the eastern Gondwana with its long axis trending north northwest-south southeast, and it belonged to a passive continental margin dipping to the north northwest, with the eastern part of the margin located closer to the eastern Gondwana. The Hexi Corridor is part of the Alxa Block and a part of the same slope basin during the early Paleozoic. The southern boundary of the Alxa Block is now the front thrust of the North Qilian Shan.

  1. Planck intermediate results. XII: Diffuse Galactic components in the Gould Belt System

    CERN Document Server

    Ade, P A R; Alves, M I R; Arnaud, M; Ashdown, M; Atrio-Barandela, F; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Bartlett, J G; Battaner, E; Bedini, L; Benabed, K; Benoît, A; Bernard, J -P; Bersanelli, M; Bonaldi, A; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Burigana, C; Butler, R C; Chen, X; Chiang, L -Y; Christensen, P R; Clements, D L; Colombi, S; Colombo, L P L; Coulais, A; Cuttaia, F; Davies, R D; Davis, R J; de Bernardis, P; de Zotti, G; Delabrouille, J; Dickinson, C; Diego, J M; Dobler, G; Dole, H; Donzelli, S; Doré, O; Douspis, M; Dupac, X; Enßlin, T A; Finelli, F; Forni, O; Frailis, M; Franceschi, E; Galeotta, S; Ganga, K; Génova-Santos, R T; Ghosh, T; Giard, M; Giardino, G; Giraud-Héraud, Y; González-Nuevo, J; Górski, K M; Gregorio, A; Gruppuso, A; Hansen, F K; Harrison, D; Hernández-Monteagudo, C; Hildebrandt, S R; Hivon, E; Hobson, M; Holmes, W A; Hornstrup, A; Hovest, W; Huffenberger, K M; Jaffe, T R; Jaffe, A H; Juvela, M; Keihänen, E; Keskitalo, R; Kisner, T S; Knoche, J; Kunz, M; Kurki-Suonio, H; Lagache, G; Lähteenmäki, A; Lamarre, J -M; Lasenby, A; Lawrence, C R; Leach, S; Leonardi, R; Lilje, P B; Linden-Vørnle, M; Lubin, P M; Macías-Pérez, J F; Maffei, B; Maino, D; Mandolesi, N; Maris, M; Marshall, D J; Martin, P G; Martínez-González, E; Masi, S; Massardi, M; Matarrese, S; Mazzotta, P; Melchiorri, A; Mennella, A; Mitra, S; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; Osborne, S; Oxborrow, C A; Pajot, F; Paladini, R; Paoletti, D; Peel, M; Perotto, L; Perrotta, F; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Popa, L; Poutanen, T; Pratt, G W; Prunet, S; Puget, J -L; Rachen, J P; Reach, W T; Rebolo, R; Reinecke, M; Renault, C; Ricciardi, S; Ristorcelli, I; Rocha, G; Rosset, C; Rubiño-Martín, J A; Rusholme, B; Salerno, E; Sandri, M; Savini, G; Scott, D; Spencer, L; Stolyarov, V; Sudiwala, R; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Terenzi, L; Tibbs, C T; Toffolatti, L; Tomasi, M; Tristram, M; Valenziano, L; Van Tent, B; Varis, J; Vielva, P; Villa, F; Vittorio, N; Wade, L A; Wandelt, B D; Ysard, N; Yvon, D; Zacchei, A; Zonca, A

    2013-01-01

    We perform an analysis of the diffuse low-frequency Galactic components in the Southern part of the Gould Belt system ($130^\\circ\\leq l\\leq 230^\\circ$ and $-50^\\circ\\leq b\\leq -10^\\circ$). Strong UV flux coming from the Gould Belt super-association is responsible for bright diffuse foregrounds that we observe from our position inside the system and that can help us improve our knowledge of the Galactic emission. Free-free emission and anomalous microwave emission (AME) are the dominant components at low frequencies ($\

  2. Age distribution of detrital zircons in the psammitic schist of the Sanbagawa Belt, southwest Japan

    International Nuclear Information System (INIS)

    We measured the 206Pb/238U age distribution of detrital zircons in five psammitic schist samples from the Sanbagawa Belt in east-central Shikoku and the western Kii Peninsula to constrain their depositional age. The age-distribution diagrams for the five psammitic schist samples all show that detrital zircons of 100 to 90 Ma are most abundant and the age of the youngest zircon in each sample is less than 80 Ma. Considering the age of the retrogressive metamorphism of these psammitic schists, ca. 80-60 Ma, the protoliths age of the psammitic schists is constrained to 75-70 Ma, correlative to the age of the sandstone of the Middle Shimanto Belt (Yanai, 1984). A similar age-distribution has already been reported for two psammitic schist samples from the Central Unit of the Sanbagawa Belt in the Kanto Mountains (Tsutsumi et al., 2009). Thus the Sanbagawa Belt is most widely occupied by metamorphic rocks originating from rocks of the Middle Shimanto Belt. We also measured the 206Pb/238U age distribution of detrital zircons in Turonian sandstone from the Northern Shimanto Belt in the central Kii Peninsula. The age-distribution diagram shows that detrital zircons of around 128 Ma are most abundant and the age of the youngest zircon in the sample is about 100 Ma. A similar age-distribution has already been reported from a psammitic schist sample from the Southern Unit of the Sanbagawa Belt in the Kanto Mountains, overlying the Central Unit (Tsutsumi et al., 2009). The protolith age is still younger than the metamorphic age of the eclogites in central Shikoku, ca. 120-110 Ma (Okamoto et al., 2004), which occupy the uppermost portion of the Sanbagawa Belt. Although some previous studies suggested that the Sanbagawa Belt consists of metamorphosed Late Jurassic to Early Cretaceous accretionary complex, the present study shows that the belt is largely occupied by metamorphosed Late Cretaceous rocks: the Shimanto Metamorphic Rocks of Aoki et al. (2007). As a result, the

  3. Towards a new understanding of the Neoproterozoic-early palæozoic Lufilian and northern Zambezi belts in Zambia and the Democratic Republic of Congo

    Science.gov (United States)

    Porada, Hubertus; Berhorst, Volker

    2000-04-01

    horizons of the 'Ore Formation' in Zambia and 'Series des Mines' in Katanga are related to temporarily anoxic conditions prevailing in the Roan Lagoon-Basin which had a southwest-northeast extent of ca 400 km. The lagoon-basin was subsequently filled by clastics derived from mainly northeastern sources (upper Kitwe Subgroup/Zambia; Dipeta Subgroup/Katanga). Possibly due to continental rupture in the southeastern, more advanced, segment of the rift and concomitant differential movement in the rupturing plate, the Kundelungu Basin started to open during deposition of the Mwashia Group. Opening of the extensional basin was accompanied by rifting, rapid subsidence of the affected platform segment and widespread mafic magmatism, which lasted until deposition of the Lower Kundelungu Group. The elevated margins of the rapidly subsiding Kundelungu Basin offered favourable conditions for inland glaciation during the Sturtian-Rapitan global glaciation epoch. The diamictites of the Grand Conglomát are thus dated at ca 750 Ma. Tectonogenesis in the Lufilian and Zambezi Belts is related to ca 560-550 Ma collision of the 'Angola-Kalahari Plate' (comprising the Kalahari Craton and southwestern part of the Congo Craton) and the 'Congo-Tanzania Plate' (comprising the remaining part of the Congo Craton) along a southeast-northwest trending suture linking up the southern Mozambique Belt with the West Congo Belt. Collision was accompanied by northeast directed thrusting involving deep crustal detachments and forward-propagating thrust faults that developed in platform and slope deposits below a high level thrust. In the Domes region, the platform sequence was detached from its basement and displaced for ca 150 km into the External Fold-Thrust Belt of Katanga. The large displacement was enhanced by fluids liberated from evaporite-rich mudflat deposits of the R.A.T. Subgroup. In the Zambezi Belt, northeast directed thrusting was succeeded by southwest directed backfolding and backthrusting

  4. Structural Discordance Between Neogene Detachments and Frontal Sevier Thrusts, Central Mormon Mountains, Southern Nevada

    Science.gov (United States)

    Wernicke, Brian; Walker, J. Douglas; Beaufait, Mark S.

    1985-02-01

    Detailed geologic mapping in the Mormon Mountains of southern Nevada provides significant insight into processes of extensional tectonics developed within older compressional orogens. A newly discovered, WSW-directed low-angle normal fault, the Mormon Peak detachment, juxtaposes the highest levels of the frontal most part of the east-vergent, Mesozoic Sevier thrust belt with autochthonous crystalline basement. Palinspastic analysis suggests that the detachment initially dipped 20-25° to the west and cut discordantly across thrust faults. Nearly complete lateral removal of the hanging wall from the area has exposed a 5 km thick longitudinal cross-section through the thrust belt in the footwall, while highly attenuated remnants of the hanging wall (nowhere more than a few hundred meters thick) structurally veneer the range. The present arched configuration of the detachment resulted in part from progressive "domino-style" rotation of a few degrees while it was active, but is largely due to rotation on younger, structurally lower, basement-penetrating normal faults that initiated at high-angle. The geometry and kinematics of normal faulting in the Mormon Mountains suggest that pre-existing thrust planes are not required for the initiation of low-angle normal faults, and even where closely overlapped by extensional tectonism, need not function as a primary control of detachment geometry. Caution must thus be exercised in interpreting low-angle normal faults of uncertain tectonic heritage such as those seen in the COCORP west-central Utah and BIRP's MOIST deep-reflection profiles. Although thrust fault reactivation has reasonably been shown to be the origin of a very few low-angle normal faults, our results indicate that it may not be as fundamental a component of orogenic architecture as it is now widely perceived to be. We conclude that while in many instances thrust fault reactivation may be both a plausible and attractive hypothesis, it may never be assumed.

  5. Important Summer Concentrations of Seaducks in West Greenland

    DEFF Research Database (Denmark)

    Boertmann, D.; Mosbech, A.

    Aerial surveys for seaducks were conducted in West Greenland in July 1998 and 1999. Important concentrations of harlequin ducks, common eiders and red-breasted mergansers were located in central and southern West Greenland, while only few king eiders had yet arrived to the moulting grounds in cen...

  6. Aeromagnetic and aeromagnetic-based geologic maps of the Coastal Belt, Franciscan Complex, northern California

    Science.gov (United States)

    Langenheim, V.E.; Jachens, R.C.; McLaughlin, R.J.

    2011-01-01

    The Coastal belt of the Franciscan Complex represents a Late Cretaceous to Miocene accretionary prism and overlying slope deposits. Its equivalents may extend from the offshore outer borderland of southern California to north of the Mendocino Triple Junction under the Eel River Basin and in the offshore of Cascadia. The Coastal belt is exposed on land in northern California, yet its structure and stratigraphy are incompletely known because of discontinuous exposure, structural disruption, and lithologically non-distinctive clastic rocks. The intent of this report is to make available, in map form, aeromagnetic data covering the Coastal belt that provide a new dataset to aid in mapping, understanding, and interpreting the incompletely understood geology and structure in northern California. The newly merged aeromagnetic data over the Coastal belt of the Franciscan Complex reveal long, linear anomalies that indicate remarkably coherent structure within a terrane where mapping at the surface indicates complex deformation and that has been described as "broken formation" and, even locally as "melange". The anomalies in the Coastal belt are primarily sourced by volcanic-rich graywackes and exotic blocks of basalt. Some anomalies along the contact of the Coastal belt with the Central belt are likely caused by local interleaving of components of the Coast Ranges ophiolite. These data can be used to map additional exotic blocks within the Coastal belt and to distinguish lithologically indistinct graywackes within the Coastal terrane. Using anomaly asymmetry allows projection of these "layers" into the subsurface. This analysis indicates predominant northeast dips consistent with tectonic interleaving of blocks within a subduction zone.

  7. Synchronous and Cogged Fan Belt Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, D.; Dean, J.; Acosta, J.

    2014-02-01

    The GSA Regional GPG Team commissioned the National Renewable Energy Laboratory (NREL) to perform monitoring of cogged V-belts and synchronous belts on both a constant volume and a variable air volume fan at the Byron G. Rodgers Federal Building and U.S. Courthouse in Denver, Colorado. These motor/fan combinations were tested with their original, standard V-belts (appropriately tensioned by an operation and maintenance professional) to obtain a baseline for standard operation. They were then switched to the cogged V-belts, and finally to synchronous belts. The power consumption by the motor was normalized for both fan speed and air density changes. This was necessary to ensure that the power readings were not influenced by a change in rotational fan speed or by the power required to push denser air. Finally, energy savings and operation and maintenance savings were compiled into an economic life-cycle cost analysis of the different belt options.

  8. Belt technology stretches conveyors' coverage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-15

    With China the leading growth engine in the conveyor market, leading belt manufacturers are establishing local manufacturing plants to boost their presence. Fenner is planning to almost triple production capacity over the next three years, with a third of its investment in China. Shanxi-Phoenix Conveyor Belt Systems is a joint venture between Phoenix Conveyor Belt Systems GmbH, now part of ContiTech Ag, and its Chinese partners Lu An Mining Group Co. Ltd. and Jingcheng Anthracite Group Co. Ltd. It manufacturers steel cable belts, PVC and multi-ply belts for coal mines and power plants. Recent belt designs by FennerEurope and Metso Minerals are reported. 2 photos.

  9. New Findings in High-Pressure and Ultrahigh-Pressure Metamorphic Belt of Tongbaishan-Dabieshan Regions, Central China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The Tongbai-Dabieshan high-pressure (HP) and ultrahigh-pressure (UHP) belt is sandwiched between the Yangtze and the Sinokorean cratons. It connects the Qinling orogenic belt in the west and links toward the east to the Sulu ultrahigh-pressure (UHP) belt. At present there is a consensus that the UHP metamorphic rocks are the products of the oblique collision between the Yangtze and Sinokorean cratons during the Triassic. However, there is still a lot of controversies about the formation and exhumation of the HP- and UHP-metamorphic belts. The present research work on the composition and the structural geometry and kinetics of the HP- and UHP- metamorphic belt has shown the following new results: (1) The overall structural geometry pattern of Dabieshan is similar to the metamorphic core complex developed in the western North America; (2) The discoveries of HP and UHP metamorphic rocks in the north of Dabieshan indicate that the significance of Shuihou-Wuhe fault should be re-evaluated; (3) A series of micro-structural evidence, including the newly-found retrograde granulite facies assemblages in the garnet pyroxenites, substantiate the extensional processes following the collision event; (4) The discovery of partial melting phenomena in the UHP-metamorphic belts illuminates the relationship between the HP- and UHP metamorphic rocks and their associated granite gneiss. All of these new findings will greatly improve our understanding of the formation and exhumation of the high-pressure and ultrahigh pressure metamorphic belts.

  10. Some problems of geologic relations between the Amazon craton and east margins fold belts

    International Nuclear Information System (INIS)

    This paper deals with some geologic problems related to the limits between the Amazon craton and the fold belts developed at its margins during the Precambrian. These limits are diversified but clearly recognized. To the north, the Araguaia-Tocantins fold belt, of presumed Middle Proterozoic age, is separated from the cratonic block by a deep marginal fracture zone permeated by mafic and ultramafic rocks. The geologic, magmatic and aeromagnetic characteristics of this zone point out the presence of deep faults, supposed to be of Middle Proterozoic age. The southern Paraguay fold belt constitutes and accurated zone of linear structures supposed to be of Late Proterozoic development. Despite the great increase of knowledge during the last ten years many tectonic, stratigraphic and geochronologic problems remain unsolved. The aim of this paper is to point out some of these problems and suggest specific studies to solve them. (author)

  11. NONLINEAR DYNAMIC BEHAVIOR OF VISCOELATIC TRANSMISSION BELT

    Institute of Scientific and Technical Information of China (English)

    Li Yinghui; Gao Qing; Jian Kailin; Yin Xuegang

    2003-01-01

    The nonlinear dynamic responses of viscoelastic axially transmission belts are investigated and the Kelvin viscoelastic differential constitutive model is employed to characterize the material property of belts. The generalized equation of motion is obtained for a viscoelatic axially transmission belts with geometric nonlinearity first, and then is reduced to be a set of second-order nonlinear ordinary differential equations by applying Galerkin's method. Finally, the effects of viscosity parameter and elastic parameter and the moving velocity of the belts on the transient responses are investigated by the research of digital simulation.

  12. GOLD MINERAL PROSPECTING USING PHASED ARRAY TYPE L-BAND SYNTHETIC APERTURE RADAR (PALSAR) SATELLITE REMOTE SENSING DATA, CENTRAL GOLD BELT, MALAYSIA

    OpenAIRE

    Beiranvand Pour, Amin; Hashim, Mazlan

    2016-01-01

    The Bentong-Raub Suture Zone (BRSZ) of Peninsular Malaysia is one of the significant structural zones in Sundaland, Southeast Asia. It forms the boundary between the Gondwana-derived Sibumasu terrane in the west and Sukhothai arc in the east. The BRSZ is also genetically related to the sediment-hosted/orogenic gold deposits associated with the major lineaments and form-lines in the central gold belt Central Gold Belt of Peninsular Malaysia. In tropical environments, heavy tropical rainforest ...

  13. Brusque belt: a monocyclic evolution ?

    International Nuclear Information System (INIS)

    This paper discusses the radiometric data for the Brusque Belt (SC) where Rb-Sr isochrons, U-Pb in zircons, K-Ar in minerals and whole rock Sm-Nd model ages are available. The analysis of these results reveals two main groups, without intermediate values. The first, 500 to 800Ma., is related to magmatic and metamorphic ages and the second, 1600-2000Ma begin with the (probably) sedimentation age. A monociclic evolution is proposed, but with uncertanties in the age of the first metamorphic phase. (author)

  14. Unique recovery stage of reef communities after F/F event in a huge coral reef of Carboniferous, Southern Guizhou, China

    Institute of Scientific and Technical Information of China (English)

    GONG; Enpu; YANG; Hongying; GUAN; Changqing; SUN; Baolian

    2004-01-01

    A huge coral reef occurring in the Triticites belt of the Maping Formation, in Bianping Village, about 4 km west of Houchang Town from Ziyun County, Southern Guizhou, China is described. The coral reef has been well studied and some significant characteristics were discovered: the composition of reef-building community is very monotonous; there are only one or two builders in each reef-building stage; the dwellers are also poor in variety; the reef-building process is very simple; the reef has been separately built by various reef-building mechanisms, and there have been few parts built by two coexisting building mechanisms; the process of reef building is often discontinuous and lacks transition. All these characteristics are considered to be unique to the recovery stage of reef communities after F/F event and are representative of a process that reef communities must undergo post the catastrophe.

  15. Compliance with Use of Seat Belt among Commercial Drivers in a Nigerian Community

    Directory of Open Access Journals (Sweden)

    Oluwole C. Omolase

    2012-06-01

    Full Text Available AIM: This study aimed at determining compliance with use of seat belt among commercial intercity drivers. METHOD: This is a descriptive cross-sectional study conducted in Owo, South West Nigeria among commercial intercity drivers between June and September, 2009. Ethical clearance was obtained from the Ethical Review Committee of Federal Medical Centre, Owo, Ondo State, Nigeria prior to commencement of this study. The permission of the leadership of Road Transport Workers’ Union was also sought and obtained. Ninety intercity commercial drivers out of the estimated one hundred and sixty intercity commercial drivers in the community were enrolled in this study. Informed consent was obtained from each of the respondents. The data obtained was collated and analyzed with SPSS 15.0.1 statistical soft ware version. RESULTS: Ninety respondents were enrolled in this study. The driving experience of the respondents revealed that most respondents: 53 (58.9% had more than 20 years driving experience. Most respondents;78 (86.7% complied with use of seat belt .The main barrier to compliance with seat belt was short trip;28 (50.9%.Most respondents; 67 (74.4%were in support of penalization of defaulters. The major source of awareness about seat belt was Federal Road Safety Corps;59 (65.6%. CONCLUSION: Most respondents complied with use of seat belt. The major barrier to compliance with seat belt was short trip within the community. The Federal Road Safety Corps should enforce compliance with the use of seat belt most especially within communities. [TAF Prev Med Bull 2012; 11(3.000: 281-286

  16. Contrasting Peridotite Types in the Dabie UHP Belt, Eastern China: the Raobazhai and Bixiling Ultramafic-mafic Complex

    Institute of Scientific and Technical Information of China (English)

    Jianping Zheng; Min Sun; W. L. Griffin; Mei-Fu Zhou; Guochun Zhao

    2007-01-01

    @@ The Dabie UHP metamorphic belt, central China,contains two contrasting types of mafic-ultramafic complex. The Bixiling peridotite in the southern Dabie terrane contains abundant garnet (21.1-32.2 vol% )and thus has high CaO + Al2O3 (9.81-15.9 wt% ).

  17. Structure of the Irian Jaya Mobile BElt, Irian Jaya, Indonesia

    Science.gov (United States)

    Nash, C. R.; Artmont, G.; Gillan, M. L.; Lennie, D.; O'Connor, G.; Parris, K. R.

    1993-01-01

    Image interpretation and field investigation over the Central Ranges of Irian Jaya has provided a structural overview of the inaccessible and largely unmapped Irian Jaya Mobile Belt (IJMB) in the region bounded by longitudes 136°30'E and 141°00'E. Throughout much of the southern (para-autochthonous) part of the belt, structural facing directions are visible on imagery through selective illumination of hogbacks and cuestas formed on thick-bedded Mesozoic siliciclastics and extensive Late Cretaceous-Neogene platform carbonate sequences. North of the regional Derewo Fault Zone, the Derewo Metamorphics are regarded in part as correlatives of the "metamorphosed Om Beds" in western Papua New Guinea and display a regional structural grain parallel to the orogen. The limited extent of spectrally anomalous features associated with ultramafic rocks indicate that ophiolites are confined to the southern part of the "Irian Jaya Ophiolite Belt", which may be largely composed of metamorphic rocks. Interpreted macroscopic and megascopic structures suggest the presence of seven discrete structural domains in the IJMB. From north to south these are (1) North Coast Basin region, consisting of Paleogene-Neogene volcanics and sediments overlain by a Pliocene-Pleistocene successor basin sequence; (2) an allochthonous terrane composed of ophiolites and high-grade metamorphic rocks; (3) the Derewo metamorphic assemblage, displaying polyphase deformation; (4) a complex marginal zone within Mesozoic-Paleogene miogeoclinal sediments which includes steep duplex structures and remnant klippen; (5) a 40 to 50-km-wide partly inverted synclinorium composed of miogeoclinal sediments; (6) a regional south vergent overturned anticlinorium formed by incompetent Paleozoic sediments; and (7) a foreland thrust domain involving both Mesozoic-Cenozoic miogeoclinal cover and a deformed Neogene foreland molasse basin sequence. The regional disposition of interpreted structures in the Irian Jaya Mobile

  18. Hydrocarbon accumulations of Mississippian Berea sandstone in west-central West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Cox, D.L. (Peake Energy, Inc., Ravenswood, WV (USA))

    1988-08-01

    The Berea Sandstone is a widely recognized producer of oil and gas in the Appalachian basin. Subsurface mapping, core analysis, and production data from producing wells have been evaluated in west-central West Virginia, where the Berea Sandstone represents a wide range of nearshore and coastal environments. Fluvial system deposits are found in southern Jackson County as channel sands (Gay-Fink) and adjacent deltaic facies. Coastal sediments were deposited to the north as intertidal shoals, tidal flats, and coarse-grained tidal-creek point bars. Marine shelf sands are found to the west.

  19. Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau:Implication for geodynamic setting and duration of the Cu mineralization

    Institute of Scientific and Technical Information of China (English)

    HOU Zengqian; QU Xiaoming; WANG Shuxian; DU Andao; GAO Yongfeng; HUANG Wei

    2004-01-01

    environment. Constraint of the NS-trending rifting zones (grabens) on localization of these porphyry bodies implies that the minor east-west stretching dates back to approximately 18 Ma. Highly precise Re-Os age of the Cu mineralization event indicates that a significant east-west extension has commenced at about (14±0.5) Ma ago, which is identical to that of the normal faulting in central Tibet (13.5 Ma) and southern Tibet (14 Ma). The strong extension not only provided dilatant conduits for the migration and emplacement of the porphyry magmas pooling near the base of lithosphere, but also resulted in the rapid rising of a large volume of volatile, thus in turn constraining the temporal-spatial localization of the Gangdese porphyry Cu belt.

  20. Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geodynamic setting and duration of the Cu mineralization

    Institute of Scientific and Technical Information of China (English)

    HOU; Zengqian; QU; Xiaoming; WANG; Shuxian; DU; Andao; GAO

    2004-01-01

    environment. Constraint of the NS-trending rifting zones (grabens) on localization of these porphyry bodies implies that the minor east-west stretching dates back to approximately 18 Ma. Highly precise Re-Os age of the Cu mineralization event indicates that a significant east-west extension has commenced at about (14±0.5) Ma ago, which is identical to that of the normal faulting in central Tibet (13.5 Ma) and southern Tibet (14 Ma). The strong extension not only provided dilatant conduits for the migration and emplacement of the porphyry magmas pooling near the base of lithosphere, but also resulted in the rapid rising of a large volume of volatile, thus in turn constraining the temporal-spatial localization of the Gangdese porphyry Cu belt.

  1. Late Palaeozoic retreating and advancing subduction boundary in the New England Fold Belt, New South Wales

    International Nuclear Information System (INIS)

    Compositions of Carboniferous and Lower Permian mafic and felsic magmatic rocks from the southern New England Fold Belt, combined with a time-space evaluation of appropriate regional geological elements, indicate that Late Palaeozoic tectonic events can be simply explained in terms of ongoing west-dipping subduction. The diversity of igneous rock types and tectonostratigraphic assemblages are interpreted to reflect sequential development of a stationary (Carboniferous), retreating (Early Permian) and advancing (Late Permian) subduction boundary along the active continental margin of East Gondwana. The stationary Carboniferous subduction boundary is expressed as a dual magmatic chain comprising a volcanic arc front of intermediate-felsic volcanic rocks in the Tamworth Belt and a subparallel rear-arc chain of granitoids and rare high-K gabbroic rocks represented by the Bathurst Batholith and satellite plutons. Waning of arc-front magmatism at ca 330 Ma corresponded to climactic activity in the rear-arc between 330 Ma and 320 Ma. Subduction boundary retreat is reflected by outboard migration of magmatism into the former accretionary prism of the Tablelands Complex, represented by the ca 300 Ma S-type Hillgrove Suite granites and coeval Bakers Creek Suite gabbros. Trace-element chemistry of these gabbros, and of Lower Permian basalts in the nascent Sydney Basin, suggests generation in a backarc setting. The 290-270 Ma Sydney Basin basalts record a transition from steep to flat, N-MORB normalised chemical trends, which suggests progressive upper plate (Gondwanan) lithospheric thinning during ongoing subduction boundary retreat. The S-type Bundarra and I-type Barrington Tops granite suites formed from contrasting crustal sources in this Early Permian extensional backarc setting. A reversal to compressional deformation is recorded by the Late Permian Hunter-Bowen Orogeny, which placed the Sydney-Bowen Basin in a foreland setting. An increasing volume of volcanic material

  2. Apparatus for heat treating plastic belts

    Science.gov (United States)

    Topits, A., Jr.

    1975-01-01

    Apparatus performs programed rotating, stretching/shrinking and heat treatment necessary to fabrication of high-performance plastic belts. Belts can be treated in lengths varying from 7 to 48 in., in widths up to 1 in., and in thicknesses up to approximately 0.003 in.

  3. Parameters affecting seat belt use in Greece.

    Science.gov (United States)

    Yannis, G; Laiou, A; Vardaki, S; Papadimitriou, E; Dragomanovits, A; Kanellaidis, G

    2011-09-01

    The objective of this research is the exploration of seat belt use in Greece and particularly the identification of the parameters affecting seat belt use in Greece. A national field survey was conducted for the analytical recording of seat belt use. A binary logistic regression model was developed, and the impact of each parameter on seat belt use in Greece was quantified. Parameters included in the model concern characteristics of car occupants (gender, age and position in the car), the type of the car and the type of the road network. The data collection revealed that in Greece, the non-use of seat belt on the urban road network was higher than on the national and rural road network and young and older men use seat belts the least. The developed model showed that travelling on a national road is negative for not wearing the seat belt. Finally, the variable with the highest impact on not wearing a seat belt is being a passenger on the back seats. PMID:21452095

  4. Understanding Quaternions and the Dirac Belt Trick

    Science.gov (United States)

    Staley, Mark

    2010-01-01

    The Dirac belt trick is often employed in physics classrooms to show that a 2n rotation is not topologically equivalent to the absence of rotation whereas a 4n rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors…

  5. Situational characteristics of safety belt use.

    Science.gov (United States)

    Fockler, S K; Cooper, P J

    1990-04-01

    Past research concerning the use and nonuse of safety belts has tended to stereotype users and nonusers as distinct entities on the basis of a single observed situation. The thought processes underlying the reasons given by drivers for using or not using seat belts have not been explored. The purpose of this study was to observe belt use by a group of drivers and describe factors contributing to their use or nonuse as defined by the drivers themselves. In-depth interviews were undertaken with 239 drivers whose safety belt wearing behavior was observed in specific city or highway driving locations. Vehicle license numbers, gender, and age group of selected drivers were used to retrieve driver records and insurance policy data. Open-ended questions were asked concerning their reasons for use or nonuse and their attitudes towards safety belts and other types of traffic safety countermeasures. Driver attitudes, characteristics, and records were compared between observed safety belt user and nonuser groups to validate variables predicting use or nonuse. Respondents' descriptions of the social and personal context of their choice to use or not use safety belts provide a broader view of seat belt wearing that suggests implications for planning future enforcement and education programs. PMID:2331287

  6. Clustering of velocities in a GPS network spanning the Sierra Nevada Block, the northern Walker Lane Belt, and the Central Nevada Seismic Belt, California-Nevada

    Science.gov (United States)

    Savage, James C.; Simpson, Robert W.

    2013-01-01

    The deformation across the Sierra Nevada Block, the Walker Lane Belt, and the Central Nevada Seismic Belt (CNSB) between 38.5°N and 40.5°N has been analyzed by clustering GPS velocities to identify coherent blocks. Cluster analysis determines the number of clusters required and assigns the GPS stations to the proper clusters. The clusters are shown on a fault map by symbols located at the positions of the GPS stations, each symbol representing the cluster to which the velocity of that GPS station belongs. Fault systems that separate the clusters are readily identified on such a map. Four significant clusters are identified. Those clusters are strips separated by (from west to east) the Mohawk Valley-Genoa fault system, the Pyramid Lake-Wassuk fault system, and the Central Nevada Seismic Belt. The strain rates within the westernmost three clusters approximate simple right-lateral shear (~13 nstrain/a) across vertical planes roughly parallel to the cluster boundaries. Clustering does not recognize the longitudinal segmentation of the Walker Lane Belt into domains dominated by either northwesterly trending, right-lateral faults or northeasterly trending, left-lateral faults.

  7. The Gould's Belt distance survey

    CERN Document Server

    Loinard, L; Torres, R M; Dzib, S; Rodriguez, L F; Boden, A F

    2011-01-01

    Very Long Baseline Interferometry (VLBI) observations can provide the position of compact radio sources with an accuracy of order 50 micro-arcseconds. This is sufficient to measure the trigonometric parallax and proper motions of any object within 500 pc of the Sun to better than a few percent. Because they are magnetically active, young stars are often associated with compact radio emission detectable using VLBI techniques. Here we will show how VLBI observations have already constrained the distance to the most often studied nearby regions of star-formation (Taurus, Ophiuchus, Orion, etc.) and have started to provide information on their internal structure and kinematics. We will then briefly describe a large project (called The Gould's Belt Distance Survey) designed to provide a detailed view of star-formation in the Solar neighborhood using VLBI observations.

  8. Strategy for replacing conveyor belts in complex haulage systems

    Energy Technology Data Exchange (ETDEWEB)

    Gladysiewicz, L.; Jurdziak, L.; Masella, J.

    1986-01-01

    Discusses service life and reliability of conveyor belts used for mine haulage in brown coal surface mining and a method for optimizing belt service life. Based on analysis of operation of 900-1,200 m long belt conveyors in the Konin surface mine, failure rates and factors that influence belt reliability were determined. Effects of joints, length of belt sections and service life of each belt section were analyzed. Formulae for determining the optimum time interval for replacing belt sections on a long belt conveyor were derived. The formulae consider cost of new belt sections, replacement cost and haulage losses associated with possible belt failure caused by excessive belt service life. The optimization procedure has been successfully tested at the Turow surface mine and power plant. 4 refs.

  9. Main-Belt Comet P/2012 T1 (PANSTARRS)

    CERN Document Server

    Hsieh, Henry H; Novakovic, Bojan; Yang, Bin; Haghighipour, Nader; Micheli, Marco; Denneau, Larry; Fitzsimmons, Alan; Jedicke, Robert; Kleyna, Jan; Veres, Peter; Wainscoat, Richard J; Ansdell, Megan; Elliott, Garrett T; Keane, Jacqueline V; Meech, Karen J; Moskovitz, Nicholas A; Riesen, Timm E; Sheppard, Scott S; Sonnett, Sarah; Tholen, David J; Urban, Laurie; Kaiser, Nick; Chambers, K C; Burgett, William S; Magnier, Eugene A; Morgan, Jeffrey S; Price, Paul A

    2013-01-01

    We present initial results from observations and numerical analyses aimed at characterizing main-belt comet P/2012 T1 (PANSTARRS). Optical monitoring observations were made between October 2012 and February 2013 using the University of Hawaii 2.2 m telescope, the Keck I telescope, the Baade and Clay Magellan telescopes, Faulkes Telescope South, the Perkins Telescope at Lowell Observatory, and the Southern Astrophysical Research (SOAR) telescope. The object's intrinsic brightness approximately doubles from the time of its discovery in early October until mid-November and then decreases by ~60% between late December and early February, similar to photometric behavior exhibited by several other main-belt comets and unlike that exhibited by disrupted asteroid (596) Scheila. We also used Keck to conduct spectroscopic searches for CN emission as well as absorption at 0.7 microns that could indicate the presence of hydrated minerals, finding an upper limit CN production rate of QCN100 Myr and is unlikely to be a rec...

  10. Polyphase thrust tectonic in the Barberton greenstone belt

    Science.gov (United States)

    Paris, I. A.

    1986-01-01

    In the circa 3.5 by-old Barberton greenstone belt, the supracrustal rocks form a thick and strongly deformed thrust complex. Structural studies in the southern part of the belt have shown that 2 separate phases of over-thrusting (D sub 1 and D sub 2) successively dismembered the original stratigraphy. Thrust nappes were subsequently refolded during later deformations (D sub 3 and D sub 4). This report deals with the second thrusting event which, in the study region appears to be dominant, and (unlike the earlier thrusting), affects the entire supracrustal pile. The supracrustal rocks form a predominantly NE/SW oriented, SE dipping tectonic fan (the D sub 2 fan) in which tectonic slices of ophiolitic-like rocks are interleaved with younger sedimentary sequences of the Diepgezet and malalotcha groups. Structural and sedimentological data indicate that the D sub 2 tectonic fan was formed during a prolonged, multi-stage regional horizontal shortening event during which several types of internal deformation mechanisms were successively and/or simultaneously active. Movement appears to have been predominantly to the NW and to the N. During D sub 2, periods of quiescence and sedimentation followed periods of thrust propagation. Although the exact kinematics which led to the formation of this fan is not yet known, paleoenvironmental interpretations together with structural data suggest that D sub 2 was probably related to (an) Archean collision(s).

  11. Seat belt use law in developing countries

    Institute of Scientific and Technical Information of China (English)

    SangWanLee

    1999-01-01

    Objective:To highlight the way to successful implementation of mandantory seat belt use law in developing countries particulary where have significant increase in number or cars and subsequent increase in car occupant casualties.Methods:Literatures concerning seat belt use were reviewed and experiences of the world.Satisfactory or not,investigated.It summed up general aspects of seat belt use as well as benefits,attitude toward legislation and measures to enhance the usage.Results:Seat belt use has been proven and stood time tested as the most effective means to protect car occupants from road crash injuries.It appears to be arduous to achieve the golal of seat belt use law in developing countries. but possible via strategies appropriately leading to legislation and promotion of the belt usage.Conclusions:It is prime necessity for the government authorities to recognize the importance of seat belt use.There needs an organizational structure composed of relevant professional from both private and government sectors which is able to carry out every steps toward successful legislation and implementation:education,publicity,enforcement,evaluation and dissemination of the law's benefits.

  12. DYNAMIC RESPONSES OF VISCOELASTIC AXIALLY MOVING BELT

    Institute of Scientific and Technical Information of China (English)

    李映辉; 高庆; 蹇开林; 殷学纲

    2003-01-01

    Based on the Kelvin viscoelastic differential constitutive law and the motion equation of the axially moving belt, the nonlinear dynamic model of the viscoelastic axial moving belt was established. And then it was reduced to be a linear differential system which the analytical solutions with a constant transport velocity and with a harmonically varying transport velocity were obtained by applying Lie group transformations. According to the nonlinear dynamic model, the effects of material parameters and the steady-state velocity and the perturbed axial velocity of the belt on the dynamic responses of the belts were investigated by the research of digital simulation. The result shows: 1 ) The nonlinear vibration frequency of the belt will become small when the relocity of the belt increases. 2 ) Increasing the value of viscosity or decreasing the value of elasticity leads to a deceasing in vibration frequencies. 3 ) The most effects of the transverse amplitudes come from the frequency of the perturbed velocity when the belt moves with harmonic velocity.

  13. Petrology of plagiogranite from Sjenica, Dinaridic Ophiolite Belt (southwestern Serbia)

    Science.gov (United States)

    Milovanović, Dragan; Srećković-Batoćanin, Danica; Savić, Marija; Popovic, Dana

    2012-04-01

    The Sjenica plagiogranite occurs in the southern part of the Dinaridic Ophiolite Belt, 5 km northwest of Sjenica. The main minerals are albite with strongly altered biotite (replaced with chlorite), with occasional amphibole (magnesio hornblende to tschermakite) and quartz. An enclave of fine-grained granitic rocks with garnet grains was noted too. Secondary minerals are calcite and chlorite (daphnite). Major, trace and REE geochemistry coupled with field observations support a model by which the Sjenica plagiogranite could be formed by fractional crystallization of mantle origin mafic magma in a supra-subduction zone setting. Occurrences of calcite and chlorite nests in the Sjenica plagiogranites revealed that these rocks underwent hydrothermal alteration due to intensive sea water circulation in a sub-sea-floor environment.

  14. From transmission error measurement to Pulley-Belt slip determination in serpentine belt drives: influence of tensioner and belt characteristics

    OpenAIRE

    Manin, Lionel; Michon, Guilhem; Rémond, Didier; Dufour, Regis

    2007-01-01

    Serpentine belt drives are often used in front end accessory drive of automotive engine. The accessories resistant torques are getting higher within new technological innovations as stater-alternator, and belt transmissions are always asked for higher capacity. Two kind of tensioners are used to maintain minimum tension that insure power transmission and minimize slip: dry friction or hydraulic tensioners. An experimental device and a specific transmission error measurement method have been u...

  15. Simulation of engine auxiliary drive V-belt slip motion. Part 1. Development of belt slip model; Engine hoki V belt slip kyodo no simulation. 1. Belt slip model no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kurisu, T. [Mazda Motor Corp., Hiroshima (Japan)

    1997-10-01

    V-belts are widely used for driving auxiliary components of an engine. Inadequet design of such belt system sometimes results in troubles such as belt squeak, side rubber separation and/or bottom rubber crack. However, there has been no design tools which can predict belt slip quantitatively. The author developed a motion simulation program of Auxiliary Drive V-Belt System considering belt slip. The program showed good prediction accuracy for belt slip motion. This paper describes the simulation model. 1 ref., 12 figs.

  16. The Compositional Structure of the Asteroid Belt

    CERN Document Server

    DeMeo, Francesca E; Walsh, Kevin J; Chapman, Clark R; Binzel, Richard P

    2015-01-01

    The past decade has brought major improvements in large-scale asteroid discovery and characterization with over half a million known asteroids and over 100,000 with some measurement of physical characterization. This explosion of data has allowed us to create a new global picture of the Main Asteroid Belt. Put in context with meteorite measurements and dynamical models, a new and more complete picture of Solar System evolution has emerged. The question has changed from "What was the original compositional gradient of the Asteroid Belt?" to "What was the original compositional gradient of small bodies across the entire Solar System?" No longer is the leading theory that two belts of planetesimals are primordial, but instead those belts were formed and sculpted through evolutionary processes after Solar System formation. This article reviews the advancements on the fronts of asteroid compositional characterization, meteorite measurements, and dynamical theories in the context of the heliocentric distribution of...

  17. Handbook Timing Belts Principles, Calculations, Applications

    CERN Document Server

    Perneder, Raimund

    2012-01-01

    Timing belts offer a broad range of innovative drivetrain solutions; they allow low-backlash operation in robot systems, they are widely used in automated processes and industrial handling involving highly dynamic start-up loads, they are low-maintenance solutions for continuous operation applications, and they can guarantee exact positioning at high operating speeds. Based on his years of professional experience, the author has developed concise guidelines for the dimensioning of timing belt drives and presents proven examples from the fields of power transmission, transport and linear transfer technology. He offers definitive support for dealing with and compensating for adverse operating conditions and belt damage, as well as advice on drive optimization and guidelines for the design of drivetrain details and supporting systems. All market-standard timing belts are listed as brand neutral. Readers will discover an extensive bibliography with information on the various manufacturers and their websites. This...

  18. Dynamics of the outer asteroid belt

    International Nuclear Information System (INIS)

    This paper considers the issue of modeling the dynamics of the outer asteroid belt. The hypotheses and assumptions of an asteroid-belt model are discussed together with their problems, of which gaps at some mean-motion resonances with Jupiter and the depletion of the outer belt are the most outstanding ones. Particular attention is given to the theory of the 2:1 gap, the depletion problem, and the mechanisms of dynamical protection against strong perturbations by Jupiter. It is suggested that the observed asteroids must have gone through a process of natural selection as a result of which all objects in unprotected orbits have been ejected from the system. Spectral observations show a reddening in spectral slope with increasing heliocentric distance; it is proposed that this is an evidence that outer-belt asteroids might be primordial objects. 41 refs

  19. Comparison of tropical nematode communities from three harbours, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Nanajkar, M.; Ingole, B.S.

    . Biol. Mar., vol.51(1); 2010; 9-18 Comparison of tropical nematode communities from the three harbours, west coast of India. Mandar Nanajkar, Baban Ingole* National Institute of Oceanography (CSIR), Dona Paula. Goa-403004, India. mandar... environmental risks linked to poor water and sediment quality (Estacio et al. 1997). The central west coast of India has dense human habitation and is an industrial belt along with extensive agriculture. The harbours in this region have heavy traffic, which...

  20. Graphite as a Biomarker in Rocks of the 3.8 Ga Isua Supracrustal Belt

    Science.gov (United States)

    Lepland, A.; van Zuilen, M.; Layne, G. D.; Arrhenius, G.

    2002-12-01

    Recent petrographic and isotopic studies of graphite and apatite in supracrustal rocks from the 3.8 Ga Isua belt (ISB) in southern West Greenland [1, 2] have shown inconsistencies in interpreting traces of life in the earliest terrestrial sediment record. Isotopically light graphitic carbon, suggestive of a bioorganic origin, has been previously reported from the carbonate-rich Isua rocks [3, 4] that at the time were recognized as sedimentary deposits. However, these carbonate-rich rocks, that provided the basis for original biologic interpretations, have been shown to have a metasomatic origin [5] not sedimentary as previously believed. This protolith reinterpretation has highlighted the need for assessment of graphite genesis and related isotopic systematics when using graphite as an ancient biomarker. We have, for this purpose, studied graphite in a suite of samples from the ISB including metacarbonates, turbidites, cherts and banded iron formations (BIFs). Graphite is relatively abundant (0.1-2 wt. %) in metacarbonate samples, while the abundances of reduced carbon in metasedimentary BIFs and metacherts are below 100 ppm. Petrographic analyses show that graphite in metacarbonates typically associates with Fe-bearing carbonate and magnetite. This mineral association indicates graphite formation in Isua metacarbonates by thermal-metamorphic reduction of carbonate ion, in which the carbonate ion is reduced to form graphite and ferrous iron is oxidized to form magnetite. Carbon isotopic compositions of graphite (δ13C ca. -2 per mil) and associated Fe-carbonate (δ13C ca. -6 per mil) indicate isotopic equilibrium between these two phases at ca. 500 C, consistent with the metamorphic history of the ISB. Stepped-combustion experiments undertaken on Isua BIFs and metacherts reveal that these sediments contain virtually no graphite, and the small amount of reduced carbon found there represents recent organic contamination. Our stepped-combustion-mass-spectrometry data

  1. Petrogenesis of Early-Permian sanukitoids from West Junggar, Northwest China: Implications for Late Paleozoic crustal growth in Central Asia

    Science.gov (United States)

    Yin, Jiyuan; Chen, Wen; Xiao, Wenjiao; Yuan, Chao; Sun, Min; Tang, Gongjian; Yu, Shun; Long, Xiaoping; Cai, Keda; Geng, Hongyan; Zhang, Yan; Liu, Xinyu

    2015-11-01

    Sanukitoids and their equivalents are rare subduction-related rock types that have been found in modern arc settings and in Late Archean sequences. The investigation of sanukitoids is of particular importance to a better understanding of crust-forming processes and continental growth. In this paper we report zircon U-Pb and Ar-Ar ages and major element, trace element, and Sr-Nd-Hf isotope data for the Bieluagaxi dioritic pluton and dikes from the southern part of the West Junggar, NW China. These rocks formed in the Early Permian and show a remarkable geochemical affinity with Cenozoic sanukitoids of the Setouchi Volcanic Belt of SW Japan with high Mg# (48-73) values, Cr (54-539 ppm), Ni (21-197 ppm) contents and Th/La (0.15-0.37) ratios and low Sr/Y ratios (16-27) and Sr (263-442 ppm) contents. They may be generated by the partial melting of subducting sediments, and subsequent melt-mantle interaction. Additionally, the sanukitoids are also widespread in the Karamay-Baogutu area of West Junggar accompanied by high Sr (average 713 ppm) contents and Sr/Y (50-130) ratios, and low Y (6.9-12.6 ppm) contents. The difference in petrochemical characteristics between the Baogutu-Karamay and Bieluagaxi sanukitoids can be explained by the difference in depth of initial melting, origin composition and fractional crystallization. The Baogutu-Karamay sanukitoids were probably formed under eclogitic conditions, while the Bieluagaxi sanukitoids were at a shallower depth. Moreover, the compositional similarity between continental-crust forming rocks and the Bieluagaxi sanukitoids suggests that the sanukitoids genesis could be closely related to the process of continental crust formation. The Late Carboniferous-Early Permian sanukitoids in the West Junggar may be an indicator of anomalous thermal activity. Ridge subduction may play a crucial role in the evolution and growth of the continental crust in Central Asia.

  2. THE GOULD'S BELT DISTANCE SURVEY

    Directory of Open Access Journals (Sweden)

    L. Loinard

    2011-01-01

    Full Text Available Observaciones que utilizan la interferometría de muy larga línea de base (VLBI por sus siglas en ingl´es pueden proveer la posición de radiofuentes compactas con una precisión del orden de 50 micro-segundos de arco. Esto es suficiente para medir la paralaje trigonométrica y los movimientos propios de cualquier objeto localizado hasta 500 pc del Sol con una precisión mejor que unos porcientos. Por ser magnéticamente activas, las estrellas jóvenes a menudo emiten emisión radio compacta detectable usando técnicas VLBI. Aquí, mostraremos cómo observaciones VLBI ya han restringido la distancia a las regiones de formación estelar cercanas más frecuentemente estudiadas (Tauro, Ofiuco, Orión, etc. y han empezado a revelar su estructura y su cinemática interna. Luego, describiremos un gran proyecto (llamado The Gould's Belt Distance Survey diseñado para proveer una vista detallada de la formación estelar en la vecindad Solar, usando observaciones VLBI.

  3. 西秦岭隧道连续皮带机出碴下的同步衬砌施工组织管理%Construction Organization Management for Synchronous Lining Casting in the Case of Continuous Belt Conveyor Mucking System:Case Study on West Qinling Tunnel

    Institute of Scientific and Technical Information of China (English)

    戴润军; 杨永强

    2011-01-01

    为减小衬砌施工与掘进施工的相互干扰,提高衬砌施工进度、缩短工期、降低工程安全风险,从设备管理、施工管理、劳动组织管理3方面介绍了TBM正常掘进时连续皮带机在出碴情况下的同步衬砌情况。通过合理的协调组织,实现了TBM掘进与衬砌施工的同步,有效缓解了本工程工期压力。%The synchronous lining casting in the case of belt conveyor mucking system during TBM boring is presented in terms of equipment management,construction management and labor organization,so as to minimize the influence between the lining casting and TBM boring,shorten the construction period and reduce the safety risks.In the end,the synchronization between TBM boring and lining casting is realized,which effectively relieves the pressure on the construction schedule.

  4. Geochemistry of metavolcanic rocks in the Archean Greenstone Belt of Identidade, SE Para, Brazil

    International Nuclear Information System (INIS)

    The paper discusses the geochemistry of the ultramafic and mafic volcanic rocks of the Identidade belt (IDB), in order to present hypothesis about their possible sources and magmatic evolution. The chemical data were obtained by ICP method. The analytical errors are less then 5% for major elements, less than 10% for the minor ones, and around 5% for trace elements. Save additional data from the meta ultramafic rocks of the Seringa belt, situated 100 km to the west of the IDB, were also considered. The XLFRAC program was employed for fractional crystallization modelling of major elements. For trace element modelling the equations of fractional crystallization and equilibrium partial melting were applied, using an unpublished program written in Pascal. 10 figs. 8 tabs

  5. Seat belts, airbags and child protection devices. [previously: Seat belts and child restraint seats.

    NARCIS (Netherlands)

    2010-01-01

    In the Netherlands, the use of seat belts results in a yearly reduction of hundreds of fatalities. Seat belts reduce the risk of fatal injury by 37 to 48%, depending on the position in the car. At 50%, the effect of child protection devices is even slightly higher. When last measured (in 2010), 97%

  6. Analysis of stress distribution of timing belts by FEM; Yugen yosoho ni yoru timing belt oryoku kaiseki (belt code oryoku bunpu kaiseki hokoku)

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, Y.; Tomono, K.; Takahashi, H.; Uchida, T. [Honda R and D Co. Ltd., Tokyo (Japan)

    1997-10-01

    A model of the belt analyzed by-ABAQUS (: a general nonlinear finite element program) successfully confirmed the mechanism that generates the belt cord stress. A quite good agreement between experimental and computed results for the stress distribution of the belt cord. It is found that maximum stress of the cords occurs near the root of the tooth by calculation, where the belt cords break off. 3 refs., 9 figs.

  7. What's West Nile Virus?

    Science.gov (United States)

    ... Help White House Lunch Recipes What's West Nile Virus? KidsHealth > For Kids > What's West Nile Virus? Print A A A Text Size en español ¿Qué es el Virus del Nilo Occidental? What exactly is the West ...

  8. Managing Soil Erosion Potential by Integrating Digital Elevation Models with the Southern China's Revised Universal Soil Loss Equation——A Case Study for the West Lake Scenic Spots Area of Hangzhou, China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In China, many scenic and tourism areas are suffering from the urbanization that results from physical development of tourism projects, leading to the removal of the vegetative cover, the creation of areas impermeable to water, in-stream modifications,and other problems. In this paper, the risk of soil erosion and its ecological risks in the West Lake Scenic Spots (WLSS) area were quantitatively evaluated by integrating the revised universal soil loss equation (RUSLE) with a digital elevation model (DEM) and geographical information system (GIS)software. The standard RUSLE factors were modified to account for local climatic and topographic characteristics reflected in the DEM maps, and for the soil types and vegetation cover types. An interface was created between the Arcinfo software and RUSLE so that the level of soil erosion and its ecological risk in the WLSS area could be mapped immediately once the model factors were defined for the area. The results from an analysis using the Arcinfo-RUSLE interface showed that the risk value in 93 % of the expanding western part of the WLSS area was moderate or more severe and the soil erosion risk in this area was thus large compared with that in the rest of the area. This paper mainly aimed to increase the awareness of the soil erosion risk in urbanizing areas and suggest that the local governments should consider the probable ecological risk resulting from soil erosion when enlarging and developing tourism areas.

  9. Paleostructural geomorphology of the Paleozoic central uplift belt and its constraint on the development of depositional facies in the Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    LIN ChangSong; YANG HaiJun; LIU JingYan; PENG Li; CAI ZhenZhong; YANG XiaoFa; YANG YongHeng

    2009-01-01

    Inclined eastward and consisting of the Hetianhe,Hetianhedong,Tazhong paleouplifts and Bachu pa-leoslope,the central paleouplift belt in the Tarim Basin was a large composite paleouplift and pa-leoslope belt with complicated palaeogeomorphic features during the Middle to early Late Ordovician.A number of paleostructural geomorphic elements have been identified in the paleouplift belt and sur-rounding areas,such as the high uplift belts,the faulted uplift platforms,the marginal slopes and slope break zones flanking the paleouplift belt,the surrounding shelf slopes or low relief ramps,the shelf slope break zones and deep basin plains.They exerted great influence on the development of paleo-geography of the basin.The marginal slopes and slope break zones flanking the uplift belt constrained the formation and deposition of the high-energy facies including reefal and shoal deposits during the Late Ordovician,which comprise the major reservoirs of the Lower Paleozoic in the basin.Toward the end of the Ordovician,the Tazhong paleouplift hinged westward and became a westward-dipped nose as the southeastern margin of the basin was strongly compressed and uplifted.The tec-tono-paleogeomorphic framework of the central northern basin during the Early Silurian and the Late Devonian to Early Carboniferous changed remarkably in topography from the initial low in east and high in west to high in northeast and low in southwest.The major paleogeomorphic elements devel-oped in these periods included the strong eroded uplift high,the uplift marginal slope,the gentle ramp of the depression margin and the depression belt.The sandstones of the Iowstand and the early transgressive systems tracts were deposited along the uplift marginal slopes and the gentle ramps of the depressions comprise the prolific reservoirs in the basin.The study indicates that the distribution patterns of the unconformities within the basin are closely related to the paleogeomorphic features and evolution of the

  10. Classification of West Virginia and Virginia Balsam Fir Communities Affected by Balsam Woolly Adelgid Infestation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Balsam fir reaches its southern limit in several high elevation wetlands in West Virginia and highelevation forests and rock outcrops in Virginia. This study...

  11. Shock melting of K-feldspar and interlacing with cataclastically deformed plagioclase in granitic rocks at Toqqusap Nunaa, southern West Greenland: Implications for the genesis of the Maniitsoq structure

    Science.gov (United States)

    Keulen, Nynke; Garde, Adam A.; Jørgart, Tommy

    2015-11-01

    Folded sheets of Mesoarchaean, leucocratic plagioclase-K-feldspar-mesoperthite-bearing granitic rocks in the Toqqusap Nunaa area of the Maniitsoq structure, West Greenland, are characterised by their very fine grain sizes and microstructures without normal igneous or planar/linear tectonic fabrics. Quartz forms equidimensional and branching, ductilely deformed aggregates and bifurcating panels with protrusions, constrictions and chains of ball-shaped grains with healed, radiating intergranular fractures. Plagioclase (An10-20) was cataclastically deformed and comminuted, whereas K-feldspar and mesoperthite are devoid of cataclastic microstructures. K-feldspar forms dispersed, highly irregular grains with numerous cusps and saddles, indicating almost ubiquitous direct (shock) melting of this mineral. It is commonly located along former fractures in plagioclase, resulting in an 'interlaced' feldspar microstructure with contact shapes indicating subsequent melting of plagioclase directly adjacent to K-feldspar. Mesoperthite forms separate, rounded, and irregular grains with protrusions and cusped margins indicating crystallisation from melts. Some mesoperthite grains are texturally and compositionally heterogeneous and contain internal lenses of K-feldspar and/or plagioclase. Other mesoperthite grains comprise coarsened, 'unzipped' areas, presumably due to localised, fluid-controlled dissolution-reprecipitation processes. The ternary feldspar precursor of the mesoperthite is interpreted as having crystallised from variably effectively mixed K-feldspar shock melts and plagioclase contact melts. Direct melting of K-feldspar, but no whole-rock melting, requires shock metamorphism with a short-lived temperature excursion to above the melting temperature of K-feldspar (~ 1300 °C). The presence of three different feldspar species and absence of chemical zonation, magmatic mantling, or metamorphic coronas furthermore hinders interpretations solely by means of endogenic

  12. The Compositions of Kuiper Belt Objects

    CERN Document Server

    Brown, Michael E

    2011-01-01

    Objects in the Kuiper belt are small and far away thus difficult to study in detail even with the best telescopes available at earth. For much of the early history of the Kuiper belt, studies of the compositions of these objects were relegated to collections of moderate quality spectral and photometric data that remained difficult to interpret. Much early effort was put into simple correlations of surface colors and identifications of spectral features, but it was difficult to connect the observations to a larger understanding of the region. The last decade, however, has seen a blossoming in our understanding of the compositions of objects in the Kuiper belt. This blossoming is a product of the discoveries of larger -- and thus easier to study -- objects, continued dedication to the collection of a now quite large collection of high quality photometric and spectroscopic observations, and continued work at the laboratory and theoretical level. Today we now know of many processes which affect the surface compos...

  13. Lubricants for Metal Belt Continuously Variable Transmissions

    Directory of Open Access Journals (Sweden)

    Keiichi Narita

    2014-02-01

    Full Text Available This paper reviews the effects of lubricant additives and base stock used in metal belt continuously variable transmissions (CVT fluids on the CVT transmission torque capacity. Additive formulation composed of phosphorus anti-wear agent, calcium detergent, and dispersant improved the friction coefficient between the metals. The analysis on the post-test surface suggests that the friction behavior strongly depends on the local morphology of the tribofilms derived from lubricant additives. Examining the effect of base stock on the torque capacity in actual belt CVTs revealed that SN (synthetic naphthene exhibited 10% higher torque capacity than that of PAO (polyalphaolefin. It is believed that the difference in the torque capacity is due to the difference in the oil-film shearing force generated by the relative sliding between the belt and pulley.

  14. A shell model for tyre belt vibrations

    Science.gov (United States)

    Lecomte, C.; Graham, W. R.; Dale, M.

    2010-05-01

    We present a new formulation for the prediction of tyre belt vibrations in the frequency range 0-500 Hz. Our representation includes the effects of belt width, curvature and anisotropy, and also explicitly models the tyre sidewalls. Many of the associated numerical parameters are fixed by physical considerations; the remainder require empirical input. A systematic and general approach to this problem is developed, and illustrated for the specific example of a Goodyear Wrangler tyre. The resulting predictions for the radial response to radial forcing show good correspondence with experiment up to 300 Hz, and satisfactory agreement up to 1 kHz.

  15. WASCAL - West African Science Service Center on Climate Change and Adapted Land Use Regional Climate Simulations and Land-Atmosphere Simulations for West Africa at DKRZ and elsewhere

    Science.gov (United States)

    Hamann, Ilse; Arnault, Joel; Bliefernicht, Jan; Klein, Cornelia; Heinzeller, Dominikus; Kunstmann, Harald

    2014-05-01

    Changing climate and hydro-meteorological boundary conditions are among the most severe challenges to Africa in the 21st century. In particular West Africa faces an urgent need to develop effective adaptation and mitigation strategies to cope with negative impacts on humans and environment due to climate change, increased hydro-meteorological variability and land use changes. To help meet these challenges, the German Federal Ministry of Education and Research (BMBF) started an initiative with institutions in Germany and West African countries to establish together a West African Science Service Center on Climate Change and Adapted Land Use (WASCAL). This activity is accompanied by an establishment of trans-boundary observation networks, an interdisciplinary core research program and graduate research programs on climate change and related issues for strengthening the analytical capabilities of the Science Service Center. A key research activity of the WASCAL Competence Center is the provision of regional climate simulations in a fine spatio-temporal resolution for the core research sites of WASCAL for the present and the near future. The climate information is needed for subsequent local climate impact studies in agriculture, water resources and further socio-economic sectors. The simulation experiments are performed using regional climate models such as COSMO-CLM, RegCM and WRF and statistical techniques for a further refinement of the projections. The core research sites of WASCAL are located in the Sudanian Savannah belt in Northern Ghana, Southern Burkina Faso and Northern Benin. The climate in this region is semi-arid with six rainy months. Due to the strong population growth in West Africa, many areas of the Sudanian Savannah have been already converted to farmland since the majority of the people are living directly or indirectly from the income produced in agriculture. The simulation experiments of the Competence Center and the Core Research Program are

  16. 南疆西部近10年沙尘暴特征分析%Analysis on the climatic characteristics of the sandstorm in the west of Southern Xinjiang in recent ten years

    Institute of Scientific and Technical Information of China (English)

    周向玲; 刘皑国; 阿不都米吉提; 张伟; 俞胜清

    2012-01-01

    Based on the sandstorm data collected from the four meteorological stations in western Shache, Markit, Bachu and Kashgar of Southern Xinjiang in recent 10 years, the time and speed characteristics of the sandstorms were studied. The results show that dust storm frequency has tapered year by year in recent 10 years. Kashgar's dust storms tapered more in the first three years. In the last two years, frequencies still decreased in Kashgar, but it increased in Shache and Markit. The sandstorms mainly occurred from April to June, erpecially in April. The dust storms mainly occurred at 20 : 00 in the evening, with a maximum duration of about 10 h happening in shache, Markit and Bachu. The average wind speed of sandstorms of the 4 places was different from each other. As there is a higher climate testing level in recent years, data acquisition for 1 times changes from 10 minutes to 1 minute. The sandstorm characteristics of wind speed were more accurately studied. Wind speed characteristics of the longest duration time of the two sandstorms were analyzed in Bachu and Markit. The wind direction is respectively northwest in Markit and northeast in Bachu. The wind speed changed obviously in Markit, with an average reriodic variation of 4 minutes, and is of obvious of gust characteristics.%对新疆南疆西部莎车县、麦盖提县、巴楚县和喀什市4地的4个气象站近10年发生的沙尘暴数据资料进行了统计分析,研究了沙尘暴发生的时间特征和风速特征.结果表明:4地沙尘暴均多发生在4~6月份,且4月份发生沙尘暴次数最多.沙尘暴发生在傍晚20:00时段频数最多,其中莎车县、麦盖提县和巴楚县沙尘暴持续时间最长为10h左右.10年间喀什市的沙尘暴每年发生次数逐渐减少.4地发生沙尘暴的平均风速不同,风向多以西北风和东北风为主.发生沙尘暴时风速大小变化幅度大,平均变化周期为4 min左右,有明显的阵风特点.

  17. Timing belts - development, milestones and innovations; Zahnriemen Entwicklungsmeilensteine und Innovationen

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, H. [Contitech Power Transmission Group (Germany)

    2005-12-01

    Contitech has much contributed to improve the characteristics of timing belts until today. In this article Contitech introduces some current developments and shows the advantages of belts compared to chain drives. (orig.)

  18. 近千年中国东部夏季雨带位置的变化%Variations of Geographical Latitude of Summer Rain Belts over Eastern China During the Last Millennium

    Institute of Scientific and Technical Information of China (English)

    黄建斌; 王绍武

    2007-01-01

    Based on the variations of geographical locations, the summer rain belts over eastern China were classified in this study into eight types: Inner Mongolia, North China, the Yellow River, the Huaihe River, the Yangtze River, the northern and southern parts of Jiangnan ( to the south of the lower Yangtze River valley), and South China. The file of 8-type rain belts was compiled from 1470 to 2005, and in order to extend the file of rain belts, it was further merged into a file of 4-type rain belts and also completed during the last millennium from 1000 to 1999. At last, the two files show that summer rain belts frequently occur in the Yangtze River valley in warm climate periods, but in the Yellow River or the Huaihe River valley in cold periods.

  19. Estimation of the internal structure of Trans-Mexican volcanic belt by gravimetric data

    International Nuclear Information System (INIS)

    The regional gravimetric data of Trans-Mexican volcanic belt and surroundings, has been analyzed in order to estimate the depth of its internal structure. The short profiles with N-S orientation give a model of four shells with an average depth in the rank 24, 34, 56 and 83 kilometers. Only the profiles included between 97 West degrees to 102 West degrees give a depth of crust larger than the rest of the profiles with the same orientation. This profiles are associated with that of the Valleys of Toluca, D.F. and Puebla where the maximum crust thickness was estimated. The 3 long profiles with S-W orientation, give a model of 3 shells. The tendency of the first shell has a cortical thickness of 38 kilometers in the latitude of 18 North degrees. This tendency to increase the depth in the crust is associated with the minimum gravimetric in the map of Bouguer anomaly. (Author)

  20. Paleozoic archipelagic tectonic evolution of Western Junggar, NW China: implications for continental growth of southern Altaids

    Science.gov (United States)

    Zhang, Jien; Xiao, Wenjiao; Han, Chunming; Ma, Chong; Song, Dongfang

    2013-04-01

    The Western Junggar, NW China, a dominant site for continental growth in Southern Altaids, bridges the Circum-Balkhash and Junggar belts and exposes ophiolite, igneous rocks and strata from Cambrian to Carboniferous. Recent updated data on structure, geochronology, geochemisty and paleomagnetism, integrated with previous data, present a newly Paleozoic spatial and temporal framework of Western Junggar. In Cambrian, the Western Junggar begins to birth at the Tangbale area to south, where occurs Ordovician blueschist and top-to-south vergence structures, indicating north-dipping subduction. This event triggers intra-arc extension to generate Ordovician island arc in the Hongguleleng-Xiemisitai area to north and seamount in the Mayile area, middle of Western Junggar. Until Silurian, a southeastward subduction begins in the extended back-arc basin to west of Mayile, occurring blueschist at the Barleik trench and the Nalunsuo magmatic arc, at the rear of which generates Devonian back-arc basin around the Durbut area. Meanwhile, a Silurian Xiemisitai magmatic arc has been developed at the northern part of Western Junggar, along which a northward subduction has emplaced the Tarbahatai ophiolite and generates the Carboniferous Sawur magmatic arc. At the middle part of Western Junggar, the coeval adakite and sanukitic dykes, charnockite, multiple properties of ophiolite and plutons, SSZ-like andesite, dacite and rhyolite and regional structures suggest that there develop double-subduction systems with ridge-trench interaction in Carboniferous. These features suggest that the Western Junggar experiences rollback, intra-oceanic extension and subduction polarity reversal/flip in back-arc basin settings. Furthermore, positive ɛNd(t) values and no huge movements of blocks suggest that the Western Junggar is amalgamated by juvenile elements with different orientations. Therefore, we conclude that the Western Junggar enlarges from an island arc to Paleozoic tectonic regime with

  1. Composite Microdiscs with a Magnetic Belt

    DEFF Research Database (Denmark)

    Knaapila, Matti; Høyer, Henrik; Helgesen, Geir

    2015-01-01

    We describe an emulsion-based preparation of patchy composite particles (diameter of 100-500 mu m) consisting of a disclike epoxy core and a belt of porous polystyrene particles (diameter of 30 mu m) with magnetite within the pores. Compared to the magnetically uniform polystyrene particles, the...

  2. West Greenlandic Eskimo

    DEFF Research Database (Denmark)

    Trondhjem, Naja Blytmann; Fortescue, Michael David

    West Greenlandic Eskimo. The current situation of the West Greenlandic language as principal means of communication among the majority Greenlandic population will be presented with special emphasis on the northwest hunting district of Upernavik, where traditional marine mammal hunting is still th...... facing immediate endangerment, althoug the minority dialects (including East Greenlandic and Polar Eskimo) face increasing pressure from the standard Central West Greenlandic dialect....

  3. The Glória quartz-monzodiorite: isotopic and chemical evidence of arc-related magmatism in the central part of the Paleoproterozoic Mineiro belt, Minas Gerais State, Brazil

    OpenAIRE

    Ciro A. Ávila; Wilson Teixeira; Umberto G. Cordani; Héctor R. Barrueto; Ronaldo M. Pereira; Veridiana T.S. Martins; Liu Dunyi

    2006-01-01

    The Glória quartz-monzodiorite, one of the mafic plutons of the Paleoproterozoic Mineiro belt, is intrusive into banded gneisses, amphibolites, schists and phyllites of the Rio das Mortes greenstone belt, in the southern portion of the São Francisco Craton, State of Minas Gerais, Brazil. The Glória quartz-monzodiorite yields a SHRIMP U-Pb zircon age of 2188 ± 29 Ma, suggesting a tectonic relationship with the pre-collisional phase of the Mineiro belt. According to the Nd isotopic evide...

  4. Antibody Prevalence of West Nile Virus in Birds, Illinois, 2002

    OpenAIRE

    Ringia, Adam M.; Blitvich, Bradley J.; Koo, Hyun-Young; Van de Wyngaerde, Marshall; Brawn, Jeff D.; Novak, Robert J

    2004-01-01

    Antibodies to West Nile virus were detected in 94 of 1,784 Illinois birds during 2002. Captive and urban birds had higher seropositivity than did birds from natural areas, and northern and central Illinois birds’ seropositivity was greater than that from birds from the southern sites. Adult and hatch-year exposure rates did not differ significantly.

  5. Ambient noise tomography across the southern Alaskan Cordillera

    Science.gov (United States)

    Ward, Kevin M.

    2015-05-01

    I present the results of an extensive data mining effort integrating 197 permanent and temporary seismic stations into a Rayleigh wave ambient noise study across southern Alaska and westernmost Canada. Principal observations of my tomography model are largely consistent with mapped geology features and previous geophysical studies while providing previously unavailable, laterally continuous details of the southern Alaskan Cordillera lithosphere. At intermediate periods, a geophysically uniform crust is observed north of the Denali Fault and is consistent with a sharp transition in crustal thickness. Under the Wrangell volcanic belt, a prominent low-phase-velocity anomaly correlates well with the lateral extent of a relative low-gravity anomaly and Neogene surface volcanics. At longer periods, a low-phase-velocity anomaly bounds the inferred eastern extent of the subducted Yakutat microplate beneath the Wrangell volcanic belt.

  6. Imaging Jupiter Radiation Belts At Low Frequencies

    Science.gov (United States)

    Girard, J. N.; de Pater, I.; Zarka, P.; Santos-Costa, D.; Sault, R.; Hess, S.; Cecconi, B.; Fender, R.; Pewg, Lofar

    2014-04-01

    The ultra-relativistic electrons, trapped in the inner radiation belts of Jupiter, generates a strong synchrotron radio emission (historically known as the jovian decimeter radiation (DIM)) which is beamed, polarized (~20% linear, ~1% circular) and broadband. It has been extensively observed by radio telescopes/ probes and imaged by radio interferometers over a wide frequency spectrum (from >300 MHz up to 22 GHz). This extended emission presents two main emission peaks constantly located on both sides of the planet close to the magnetic plane. High latitude emissions were also regularly observed at particular frequencies, times and in particular observational configurations. This region of the magnetosphere is "frozen" due to the strong magnetic field (~4.2 G as the equator) and therefore is forced to rotate at the planetary period (T≈9h55m). Due to the tilt (~ 10o) between the spin axis of the planet and the magnetic axis (which can be seen as dipolar in first approximation), the belts and the associated radio emission wobble around the planet center. The analysis of the flux at different frequencies highlighted spatial, temporal and spectral variabilities which origins are now partly understood. The emission varies at different time scales (short-time variations of hours to long-term variation over decades) due to the combination of visibility effect (wobbling, beaming, position of the observer in the magnetic rotating reference frame) [1], [2] and intrinsic local variations (interaction between relativistic electrons and satellites/dust, delayed effect of the solar wind ram pressure, impacts events) [3], [4], [5]. A complete framework is necessary to fully understand the source, loss and transport processes of the electrons originating from outside the belt, migrating by inward diffusion and populating the inner region of the magnetosphere. Only a few and unresolved measurements were made below 300 MHz and the nonsystematic observation of this radio emission

  7. The Modi Taung-Nankwe gold district, Slate belt, central Myanmar: mesothermal veins in a Mesozoic orogen

    Science.gov (United States)

    Mitchell, A. H. G.; Ausa, C. A.; Deiparine, L.; Hlaing, T.; Htay, N.; Khine, A.

    2004-07-01

    The recently discovered quartz-gold veins comprising the Modi Taung-Nankwe gold district in central Myanmar are largely hosted by mudstones of the late Palaeozoic Slate belt. Mesozoic rocks of the Paunglaung-Mawchi zone separate the Slate belt from the Shan Scarp and Shan Plateau to the east. At Modi Taung 5 km of exploration adits indicate that the veins, within steeply dipping oblique reverse-slip shear zones, are displaced by movements along the shears, intruded by late Jurassic calc-alkaline dykes, and offset on conjugate cross-faults. Drill intercepts show that mineralization extends vertically for more than 500 m. Coarse visible gold, book-and-ribbon texture and stylolitic laminations, and trace metal values are consistent with mineralization at mesothermal depths of several kilometres in the brittle-ductile regime. Our field observations suggest that mineralization took place in the early Jurassic following collision of Myanmar on the passive western margin of a Greater Shan-Thai continental block with an oceanic arc on the overriding plate to the west. Collision generated intra-continental thrusting in and east of the Paunglaung-Mawchi zone, metamorphism of Plateau rocks thrust west beneath the Slate belt to form the Mogok Metamorphics, and ascent of mineralizing fluids expelled from dehydrating underthrust rocks. Reversal in orogenic polarity initiated late Jurassic eastward subduction of oceanic crust beneath Myanmar, and generation of a magmatic arc with dykes cutting the quartz-gold veins. Renewed east-directed thrusting translated the Slate belt over arc clastics, and probably resulted in exhumation of the Mogok Metamorphics and offsets of the veins on conjugate faults. Young K/Ar, Rb 87/Sr 86 and Ar 40/Ar 39 ages on the Mogok Metamorphic belt imply renewed Tertiary uplift and possibly intrusion of mid-Tertiary or Palaeogene granites.

  8. Crustal architecture of the southern Uralides from true amplitude processing of the Urals Seismic Experiment and Integrated Studies (URSEIS) vibroseis profile

    Science.gov (United States)

    Tryggvason, A.; Brown, D.; PéRez-Estaún, A.

    2001-12-01

    True amplitude processing of the Urals Seismic Experiment and Integrated Studies (URSEIS) vibroseis deep reflection seismic data acquired by the URSEIS consortium shows the southern Uralide crust to be composed of four major blocks with distinctive reflection characteristics. These blocks are juxtaposed along crustal-scale boundaries. The foreland thrust and fold belt, developed from the East European craton crust, is imaged as subhorizontal to east dipping reflectivity that can be related to its Paleozoic and older tectonic history. The Moho beneath the foreland thrust and fold belt is not imaged in the vibroseis data set. The Main Uralian fault (the major arc-continent suture) is unreflective, but its subsurface location can be inferred by the truncation of the reflection pattern of the East European craton and its contrast with that of the Magnitogorsk arc. The Magnitogorsk arc reflectivity is characterized by patchy, noncoherent to coherent reflections in the upper ˜10 - 15 km that are interpreted to be related to the arc volcanic rocks. Below this, reflectivity is diffuse, or the arc crust is transparent, and the Moho is not imaged. The East Magnitogorsk fault zone, which juxtaposes the arc against the East Uralian zone, is not imaged by the data. The upper 5 to 6 km of the East Uralian zone, corresponding to the Dzhabyk granite, is transparent. Below the granite the crust is characterised by east dipping patches of moderately coherent, high-amplitude reflections that in the east become shallowly west-dipping. A ˜10 km thick, west dipping band of coherent, high amplitude reflections between 12 and 35 km depth, corresponding to the Kartaly Reflection Sequence, extends beneath almost the entire East Uralian zone. The crust beneath the easternmost East Uralian zone reaches 53 km in thickness. The upper and middle crust of the Trans-Uralian zone is characterized by a series of east and west dipping, concave upward, moderately coherent, high-amplitude reflections

  9. Influence of Salt Beds on the Segmentation of Structure and Hydrocarbon Accumulation in Qiulitag Structural Belt, Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    Fan Qiuhai; Lü Xiuxiang; Yang Minghui; Xie Huiwen

    2008-01-01

    Seismic information and balanced profile technology were used to reveal the influence of the salt bed in segmentation of structure and hydrocarbon accumulation in Qiulitag structural belt in Tarim basin. From west to east, the shortening of strata above the salt beds gradually decreases, while,the shortening below the salt beds gradually increases, which shows that the segmentation of structure integrated the seismic profile. There is great difference of the deformation of strata below and above the salt beds between the west segment and the east segment. The analysis of the distribution of oil/gas fields and the hydrocarbon properties indicates the similar segmentation to the structure segmentation.The salt beds in relatively shallow layers change the stress condition from basement of Kuqa foreland basin, which leads to the segmentation of Qiulitag structural belt. Because the salt beds in the west segment came into being earlier than those in the east segment, the west segment captures hydrocarbon from two sets of source rock, while the east segment can only capture hydrocarbons from one set of source rock. So, the salt beds play an important role in the segmentation of structure and hydrocarbon accumulation.

  10. Imaging Jupiter's radiation belts down to 127 MHz with LOFAR

    CERN Document Server

    Girard, J N; Tasse, C; Hess, S; de Pater, I; Santos-Costa, D; Nenon, Q; Sicard, A; Bourdarie, S; Anderson, J; Asgekar, A; Bell, M E; van Bemmel, I; Bentum, M J; Bernardi, G; Best, P; Bonafede, A; Breitling, F; Breton, R P; Broderick, J W; Brouw, W N; Brüggen, M; Ciardi, B; Corbel, S; Corstanje, A; de Gasperin, F; de Geus, E; Deller, A; Duscha, S; Eislöffel, J; Falcke, H; Frieswijk, W; Garrett, M A; Grießmeier, J; Gunst, A W; Hessels, J W T; Hoeft, M; Hörandel, J; Iacobelli, M; Juette, E; Kondratiev, V I; Kuniyoshi, M; Kuper, G; van Leeuwen, J; Loose, M; Maat, P; Mann, G; Markov, S; McFadden, R; McKay-Bukowski, D; Moldon, J; Munk, H; Nelles, A; Norden, M J; Orru, E; Paas, H; Pandey-Pommier, M; Pizzo, R; Polatidis, A G; Reich, W; Röttgering, H; Rowlinson, A; Schwarz, D; Smirnov, O; Steinmetz, M; Swinbank, J; Tagger, M; Thoudam, S; Toribio, M C; Vermeulen, R; Vocks, C; van Weeren, R J; Wijers, R A M J; Wucknitz, O

    2015-01-01

    Context. Observing Jupiter's synchrotron emission from the Earth remains today the sole method to scrutinize the distribution and dynamical behavior of the ultra energetic electrons magnetically trapped around the planet (because in-situ particle data are limited in the inner magnetosphere). Aims. We perform the first resolved and low-frequency imaging of the synchrotron emission with LOFAR at 127 MHz. The radiation comes from low energy electrons (~1-30 MeV) which map a broad region of Jupiter's inner magnetosphere. Methods (see article for complete abstract) Results. The first resolved images of Jupiter's radiation belts at 127-172 MHz are obtained along with total integrated flux densities. They are compared with previous observations at higher frequencies and show a larger extent of the synchrotron emission source (>=4 $R_J$). The asymmetry and the dynamic of east-west emission peaks are measured and the presence of a hot spot at lambda_III=230 {\\deg} $\\pm$ 25 {\\deg}. Spectral flux density measurements ar...

  11. Low- to high-grade metamorphic transition in the Southern part of Karnataka Nucleus, India

    Science.gov (United States)

    Naqvi, S. M.

    The southern part of Karnataka Nucleus has a strong imprint of 2.6 Ga metamorphism. This has affected the schist belts of Karnataka Nucleus from greenschist to upper amphibolite facies. The higher grades of metamorphism are in the Holenarasipur, Nuggihalli, Krishnarajpet, Hadnur and Melkote schist belts. In the high grade transition zone, around Sargur only keels of schist belts are preserved and occur as highly dismembered, disconnected belts with the top and bottom of the stratigraphic column obliterated due to high grade metamorphism and accompanying migmatization. Absence of high-grade metamorphic minerals in the sediments of the Dharwar schist belts supports the contention that high grade metamorphism post-dated the Dharwar sedimentation and occurred around 2.6 Ga ago. Sargur type metamorphism occurred at upper crustal levels and charnockite type metamorphism occurred in lower crustal levels. The P-T conditions for the mineral assemblage in metapelites of Sargur Group indicate burial depths up to at least 15 km suggesting that they were subducted and later obducted during the development of Early Proterozoic Mobile Belt along the southern border of the Karnataka Nucleus.

  12. Detecting Extrasolar Asteroid Belts Through Their Microlensing Signatures

    CERN Document Server

    Lake, Ethan; Dong, Subo

    2016-01-01

    We propose that extrasolar asteroid belts can be detected through their gravitational microlensing signatures. Asteroid belt + star lens systems create so-called "pseudo-caustics", regions in the source plane where the magnification exhibits a finite but discontinuous jump. These features allow such systems to generate distinctive microlensing light curves across a wide region of belt parameter space and possess remarkably large lensing cross-sections. Sample light curves for a range of asteroid belt parameters are presented. In the near future, space-based microlensing surveys (e.g., WFIRST) may be able to discover extrasolar asteroid belts with masses of the order of $0.1 M_{\\oplus}$.

  13. Geometry and modeling of an active offshore thrust-related fold system: the Amendolara Ridge, Ionian Sea, southern Italy

    OpenAIRE

    L. Ferranti; Pepe, F.; P. Burrato; Santoro, E.; Mazzella, ME; Morelli, D; Passaro S; G. Vannucci

    2012-01-01

    On the Ionian Sea coast of southern Italy, spanning the transition from the Calabrian Arc to the Apennines, NE-directed motion of the thin-skinned frontal thrust belt of the Apennines toward the Apulian foreland reportedly ceased during the Early-Middle Pleistocene. The submarine extension of the frontal thrust belt is represented by the Amendolara ridge, which stretches for over 80 km to the SE beneath the Taranto Gulf. High-resolution marine geophysical data collected on the Amendolara ridg...

  14. Modelling of current crustal tectonic deformation in the Chinese Tianshan orogenic belt constrained by GPS observations

    International Nuclear Information System (INIS)

    It is important to discover the deformation characteristics of the Tianshan mountain range for a better understanding of the geodynamics of the Tianshan orogenic belt. Constrained by the GPS-derived velocity vectors of crustal movement, the current velocity field, stress field and strain rate in the Tianshan mountains have been retrieved from a three-dimensional numerical model presented in this paper by using the finite-element code ANSYS, on the basis of geological structures, tectonic regimes, active fault belts and seismic velocity structures of the crust and upper mantle. The results suggest that: (1) the general direction of crustal movement is NNE, and yet gradually turns to NE from west to east; (2) the regional stress field is characterized by near N–S tectonic compression, resulting in crustal shortening in the near N–S direction as well; and (3) the shortening strain rate is ∼10−8 a−1 and decreases gradually from west to east. Our results support the opinion that the crustal deformation of the Tianshan mountain range is controlled by the clockwise rotation of the Tarim basin

  15. Call From China West

    Institute of Scientific and Technical Information of China (English)

    Yang Wei; Guo Jin

    2008-01-01

    @@ The 12th East-West China Cooperation and Investment and Trade Fair was held from April 5 to 8 at the International Conference and Exhibition Center in Qu-jiang,Xi'an.Shaanxi province,in the west of China.

  16. Seat Belt Use Among Adult Workers - 21 States, 2013.

    Science.gov (United States)

    Boal, Winifred L; Li, Jia; Rodriguez-Acosta, Rosa L

    2016-01-01

    Roadway incidents involving motorized vehicles accounted for 24% of fatal occupational injuries in the United States during 2013 and were the leading cause of fatal injuries among workers.* In 2013, workers' compensation costs for serious, nonfatal injuries among work-related roadway incidents involving motorized land vehicles were estimated at $2.96 billion.(†) Seat belt use is a proven method to reduce injuries to motor vehicle occupants (1). Use of lap/shoulder seat belts reduces the risk for fatal injuries to front seat occupants of cars by 45% and the risk to light truck occupants by 60%.(§) To characterize seat belt use among adult workers by occupational group, CDC analyzed data from the 2013 Behavioral Risk Factor Surveillance System (BRFSS) and found that not always using a seat belt was significantly associated with occupational group after controlling for factors known to influence seat belt use. Occupational groups with the highest prevalences of not always using a seat belt included construction and extraction; farming, fishing, and forestry; and installation, maintenance, and repair. To increase seat belt use among persons currently employed, states can enact and enforce primary seat belt laws, employers can set and enforce safety policies requiring seat belt use by all vehicle occupants, and seat belt safety advocates can target interventions to workers in occupational groups with lower reported seat belt use. PMID:27309488

  17. LOAD DISTRIBUTION ON DRUMS OF DOUBLE DRIVE BELT CONVEYOR

    Institute of Scientific and Technical Information of China (English)

    薛河; 苏清祖; 马胜利

    1999-01-01

    The double drum drive is widely used on the mine belt conveyor, which are divided the rigid connected double drums and separately driving double drums according to connected method of two drums. Because of the change of real work condition, the load distribution is changed on the two drive drums, which may produce a slippage between a drum and belt. Slippage may intensify the wear of the drum, and sometimes causing the fire of the belt. This restricts the development toward narrow belt, high velocity and large power of belt conveyor. In this paper, the factors affecting the load distribution of two drums of double drum belt conveyor are'systematically analyzed and some computing formulas derived, by these formulas, the actual load distribution onthe two drums of rigid connected or separately driving belt conveyor can be separately calculated. These formulas also can be as the theory base for adjusting the driving force of two drums.

  18. Discussion on the precambrlan structural framework of the Gan-Hang tectonic belt

    International Nuclear Information System (INIS)

    Progresses have been made successively on the study of the precambrian structural framework of the southern China. The comprehensive analysis and study on the precambrian formations and structures suggest that: the Cathaysia is a dismembered Early proterozoic old-land, the western Zhejiang-Northeast Jiangxi region was located at the active continental margin of the Cathaysia during the late stage of middle Proterozoic, Wuling movement is the most important orogeny in the southern China, and the collision between the Cathaysia and the Yangtze block along the Gangdongbei fault belt led to the formation of a united south China old -land. Because of different regional geological conditions, there exists evident difference in the late proterozoic tectonic evolution in different parts of the Cathaysia. During caledonian period, the studied region was developed into the Western Zhejiang Northeast Jiangxi aulacogen

  19. Structure and geological evolution of the bedrock at southern Satakunta, SW Finland

    International Nuclear Information System (INIS)

    The southern Satakunta area lies on the west coast of Finland, mainly covering the mainland (with main towns Pori and Rauma), but also including the coastal archipelago and part of the Bothnian Sea. Near the centre of the area lies the island of Olkiluoto, on which Finland's site for a deep repository for spent nuclear fuel is located. The purpose of the present report is to compile and interpret all available geological and geophysical data relevant to understanding the regional geological setting of the Olkiluoto site. The area described is covered by four 1:100 000 scale geological map sheets, published by the Geological Survey of Finland, which, together with low-altitude aeromagnetic maps, provide the basis for a new 1:250 000 geological map compilation. This shows that the bedrock of southern Satakunta can be subdivided into three main zones: a pelitic migmatite belt in the southwest, a central, NW-SE trending area of sandstone, and a psammitic migmatite belt in the northeast. The migmatite belts formed during the Svecofennian orogeny, 1900-1800 Ma ago (Palaeoproterozoic). The sandstone area is the remnant of an alluvial basin, preserved now in a NW-SE trending graben, bounded on both sides by normal fault zones. The sandstones are thought to be at least 1400-1300 Ma old (Mesoproterozoic), and they are cut by Postjotnian olivine diabase dykes, 1270-1250 Ma in age. The Svecofennian migmatite belts show a complex history of formation, with various phases of anatexis/metamorphism, deformation and intrusion. In the pelitic migmatite belt, in which the Olkiluoto site is situated, four phases of ductile deformation (D-D4) and two phases of regional highT/lowP metamorphism and migmatite formation can be recognised, together with synorogenic (tonalite, granodiotite) and late orogenic ( potassium granite) intrusions. Subsequently, this very heterogeneous complex was intruded by anorogenic rapakivi granites, with ages 1580-1550 Ma. One pluton, the Eurajoki stock

  20. Structure and geological evolution of the bedrock at southern Satakunta, SW Finland

    Energy Technology Data Exchange (ETDEWEB)

    Paulamaeki, S.; Paananen, M.; Elo, S. [Geological Survey of Finland (Finland)

    2002-02-01

    The southern Satakunta area lies on the west coast of Finland, mainly covering the mainland (with main towns Pori and Rauma), but also including the coastal archipelago and part of the Bothnian Sea. Near the centre of the area lies the island of Olkiluoto, on which Finland's site for a deep repository for spent nuclear fuel is located. The purpose of the present report is to compile and interpret all available geological and geophysical data relevant to understanding the regional geological setting of the Olkiluoto site. The area described is covered by four 1:100 000 scale geological map sheets, published by the Geological Survey of Finland, which, together with low-altitude aeromagnetic maps, provide the basis for a new 1:250 000 geological map compilation. This shows that the bedrock of southern Satakunta can be subdivided into three main zones: a pelitic migmatite belt in the southwest, a central, NW-SE trending area of sandstone, and a psammitic migmatite belt in the northeast. The migmatite belts formed during the Svecofennian orogeny, 1900-1800 Ma ago (Palaeoproterozoic). The sandstone area is the remnant of an alluvial basin, preserved now in a NW-SE trending graben, bounded on both sides by normal fault zones. The sandstones are thought to be at least 1400-1300 Ma old (Mesoproterozoic), and they are cut by Postjotnian olivine diabase dykes, 1270-1250 Ma in age. The Svecofennian migmatite belts show a complex history of formation, with various phases of anatexis/metamorphism, deformation and intrusion. In the pelitic migmatite belt, in which the Olkiluoto site is situated, four phases of ductile deformation (D-D4) and two phases of regional highT/lowP metamorphism and migmatite formation can be recognised, together with synorogenic (tonalite, granodiotite) and late orogenic ( potassium granite) intrusions. Subsequently, this very heterogeneous complex was intruded by anorogenic rapakivi granites, with ages 1580-1550 Ma. One pluton, the Eurajoki stock

  1. Crust and upper mantle electrical structure of Haiyuan-Liupanshan Thrust Belt and its vicinity revealed by magnetotelluric(MT) detection

    Science.gov (United States)

    Han, S.; Liu, G.; Han, J.

    2015-12-01

    Under the auspices of SinoProbe Project, an array of 91 broad-band magnetotelluric(MT) sites across the southern segment of the Haiyuan-Liupanshan Thrust Belt (HLTB) was occupied to determine the crust and upper mantle structure of the transition zone between the Ordos Block (OB) and the Qilian Orogenic Belt (QOB).An electrical structure model of the crust and the upper mantle was finally obtained after data processing, qualitative analysis and 2D inversion of the observed data.The model revealed the deep structure of the profile.The upper crust of the HLTB is modelled as resistive while the other two tectonic units are modelled as less resistive.The massive high resistive blocks in the upper crust are seen in the HLTB.On the contrast,the lower crust is revealed as conduvtive on the whole.Middle to lower crustal high conductive layers (HCL) are seen both in the QOB and the OB.A strong lower crust conductor is revealed in the HLTB.Electrical structure of the upper mantle is revealed as resistive,respectively.The wedge structure is seen in the uppermost mantle under the Liupanshan Mountain.According to the electrical structure of the profile,the study region can be divided into three tectonic units:the QOB,the Liupan Transition Zone (LTZ,expansion of the HLTB) and the OB.The tectonic deformation for the QB manifest as thrust nappe in the upper crust and shortening strain in the lower crust.The east-dipping conductor in the west of QOB may represent the accumulated weak material in the form of middle crust flow and the HCL of the QB may be the migration channel.The fluctuation of HCL may indicate interior deformation of the OB.The LTZ is quite different from the adjacent tectonic units that fragment structure exists in the upper crust and deep thrust faults cut through the upper crust.The conductor located in the lower crust is interpreted as partial melt zone as a result of the vertical decompression process.Joint interpretation of the electrical structure and the

  2. Petrology and geochemistry of the ~2.9 Ga Itilliarsuk banded iron formation and associated supracrustal rocks, West Greenland

    DEFF Research Database (Denmark)

    Haugaard, Rasmus; Frei, Robert; Stendal, Henrik;

    2013-01-01

    Here we present new field, petrographic and geochemical data from the ∼2.9 Ga Itilliarsuk banded iron formation (BIF) and associated lithologies within the Itilliarsuk supracrustal belt, south-eastern Nussuuaq, West Greenland. The supracrustals represent a volcanic–sedimentary sequence, which res...

  3. Southern Appalachian Regional Seismic Network

    International Nuclear Information System (INIS)

    The seismic activity in the southern Appalachian area was monitored by the Southern Appalachian Regional Seismic Network (SARSN) since late 1979 by the Center for Earthquake Research and Information (CERI) at Memphis State University. This network provides good spatial coverage for earthquake locations especially in east Tennessee. The level of activity concentrates more heavily in the Valley and Ridge province of eastern Tennessee, as opposed to the Blue Ridge or Inner Piedmont. The large majority of these events lie between New York - Alabama lineament and the Clingman/Ocoee lineament, magnetic anomalies produced by deep-seated basement structures. Therefore SARSN, even with its wide station spacing, has been able to define the essential first-order seismological characteristics of the Southern Appalachian seismic zone. The focal depths of the southeastern U.S. earthquakes concentrate between 8 and 16 km, occurring principally beneath the Appalachian overthrust. In cross-sectional views, the average seismicity is shallower to the east beneath the Blue Ridge and Piedmont provinces and deeper to the west beneath the Valley and Ridge and the North American craton. Results of recent focal mechanism studies by using the CERI digital earthquake catalog between October, 1986 and December, 1991, indicate that the basement of the Valley and Ridge province is under a horizontal, NE-SW compressive stress. Right-lateral strike-slip faulting on nearly north-south fault planes is preferred because it agrees with the trend of the regional magnetic anomaly pattern

  4. Ionic composition of the earth's radiation belts

    Science.gov (United States)

    Spjeldvik, W. N.

    1983-01-01

    Several different ion species have been positively identified in the earth's radiation belts. Besides protons, there are substantial fluxes of helium, carbon and oxygen ions, and there are measurable quantities of even heavier ions. European, American and Soviet space experimenters have reported ion composition measurements over wide ranges of energies: at tens of keV (ring-current energies) and below, and at hundreds of keV and above. There is still a gap in the energy coverage from several tens to several hundreds of keV where little observational data are available. In this review emphasis is placed on the radiation belt ionic structure above 100 keV. Both quiet time conditions and geomagnetic storm periods are considered, and comparison of the available space observations is made with theoretical analysis of geomagnetically trapped ion spatial, energy and charge state distributions.

  5. Biogeochemical cycling of cadmium isotopes in the Southern Ocean along the Zero Meridian

    NARCIS (Netherlands)

    Abouchami, W.; Galer, S.J.G.; de Baar, H.J.W.; Middag, R.; Vance, D.; Zhao, Y.; Klunder, M.; Mezger, K.; Feldmann, H.; Andreae, M.O.

    2014-01-01

    We present depth profiles of Cd isotopes and concentrations from the Southern Ocean at four stations in the Atlantic sector along the Greenwich Meridian (47 degrees S to 68 degrees S) located across the main Antarctic frontal zones and productivity belt. The vertical profiles of Cd concentration typ

  6. Precambrian crustal evolution and Cretaceous–Palaeogene faulting in West Greenland: A lead isotope study of an Archaean gold prospect in the Attu region, Nagssugtoqidian orogen, West Greenland

    OpenAIRE

    Stendal, Henrik; Frei, Robert; Stensgaard, Bo Møller

    2006-01-01

    This paper presents a lead isotope investigation of a gold prospect south of the village Attu in the northern part of the Nagssugtoqidian orogen in central West Greenland. The Attu gold prospect is a replacement gold occurrence, related to a shear/mylonite zone along a contact between orthogneissand amphibolite within the Nagssugtoqidian orogenic belt. The mineral occurrence is small, less than 0.5 m wide, and can be followed along strike for several hundred metres. The mineral assemblage is ...

  7. Alien Asteroid Belt Compared to our Own

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1: Band of Light Comparison This artist's concept illustrates what the night sky might look like from a hypothetical alien planet in a star system with an asteroid belt 25 times as massive as the one in our own solar system (alien system above, ours below; see Figure 1). NASA's Spitzer Space Telescope found evidence for such a belt around the nearby star called HD 69830, when its infrared eyes spotted dust, presumably from asteroids banging together. The telescope did not find any evidence for a planet in the system, but astronomers speculate one or more may be present. The movie begins at dusk on the imaginary world, when HD 69830, like our Sun, has begun to set over the horizon. Time is sped up to show the onset of night and the appearance of a brilliant band of light. This light comes from dust in a massive asteroid belt, which scatters sunlight. In our solar system, anybody observing the skies on a moonless night far from city lights can see the sunlight that is scattered by dust in our asteroid belt. Called zodiacal light and sometimes the 'false dawn,' this light appears as a dim band stretching up from the horizon when the Sun is about to rise or set. The light is faint enough that the disk of our Milky Way galaxy remains the most prominent feature in the sky. (The Milky Way disk is shown perpendicular to the zodiacal light in both pictures.) In contrast, the zodiacal light in the HD 69830 system would be 1,000 times brighter than our own, outshining even the Milky Way.

  8. Skin manifestations of West Nile virus infection.

    Science.gov (United States)

    Del Giudice, P; Schuffenecker, I; Zeller, H; Grelier, M; Vandenbos, F; Dellamonica, P; Counillon, E

    2005-01-01

    West Nile virus (WNV) infection is a potentially lethal arbovirus infection. Many notable outbreaks have occurred during the last few years throughout the world, including Europe and the USA. The severity of the disease is mainly related to the neurological complications. A maculopapular exanthema is reported as a clinical sign of the disease. Recently an outbreak of WNV infection occurred in southern France. Three patients out of 6 had a similar skin roseola-like eruption. The cluster of 3 cases of similar febrile roseola of unexplained cause during the same week led to the diagnosis of the first WNV human outbreak in France for 40 years. PMID:16286745

  9. Understanding quaternions and the Dirac belt trick

    International Nuclear Information System (INIS)

    The Dirac belt trick is often employed in physics classrooms to show that a 2π rotation is not topologically equivalent to the absence of rotation whereas a 4π rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors has been achieved, or if the trick is just an amusing analogy. The goal of this paper is to demystify the belt trick and to show that it suggests an underlying four-dimensional parameter space for rotations that is simply connected. An investigation into the geometry of this four-dimensional space leads directly to the system of quaternions, and to an interpretation of three-dimensional vectors as the generators of rotations in this larger four-dimensional world. The paper also shows why quaternions are the natural extension of complex numbers to four dimensions. The level of the paper is suitable for undergraduate students of physics.

  10. The atmospheric implications of radiation belt remediation

    Directory of Open Access Journals (Sweden)

    C. J. Rodger

    2006-08-01

    Full Text Available High altitude nuclear explosions (HANEs and geomagnetic storms can produce large scale injections of relativistic particles into the inner radiation belts. It is recognised that these large increases in >1 MeV trapped electron fluxes can shorten the operational lifetime of low Earth orbiting satellites, threatening a large, valuable population. Therefore, studies are being undertaken to bring about practical human control of the radiation belts, termed "Radiation Belt Remediation" (RBR. Here we consider the upper atmospheric consequences of an RBR system operating over either 1 or 10 days. The RBR-forced neutral chemistry changes, leading to NOx enhancements and Ox depletions, are significant during the timescale of the precipitation but are generally not long-lasting. The magnitudes, time-scales, and altitudes of these changes are no more significant than those observed during large solar proton events. In contrast, RBR-operation will lead to unusually intense HF blackouts for about the first half of the operation time, producing large scale disruptions to radio communication and navigation systems. While the neutral atmosphere changes are not particularly important, HF disruptions could be an important area for policy makers to consider, particularly for the remediation of natural injections.

  11. Substyles of belting: phonatory and resonatory characteristics.

    Science.gov (United States)

    Sundberg, Johan; Thalén, Margareta; Popeil, Lisa

    2012-01-01

    Belting has been described as speechlike, yell-like, or shouting voice production commonly used in contemporary commercial music genres and substantially differing from the esthetic of the Western classical voice tradition. This investigation attempts to describe phonation and resonance characteristics of different substyles of belting (heavy, brassy, ringy, nasal, and speechlike) and the classical style. A professional singer and voice teacher, skilled in these genres, served as the single subject. The recorded material was found representative according to a classification test performed by an expert panel. Subglottal pressure was measured as the oral pressure during the occlusion for the consonant /p/. The voice source and formant frequencies were analyzed by inverse filtering the audio signal. The subglottal pressure and measured flow glottogram parameters differed clearly between the styles heavy and classical assuming opposite extremes in most parameters. The formant frequencies, by contrast, showed fewer less systematic differences between the substyles but were clearly separated from the classical style with regard to the first formant. Thus, the differences between the belting substyles mainly concerned the voice source. PMID:21439776

  12. Structure of the Cordillera de la Costa Belt, North-Central Venezuela: Implications for plate tectronic models

    Energy Technology Data Exchange (ETDEWEB)

    Ave Lallemant, H.G.; Sisson, V.B.; Wright, J.E. (Rice Univ., Houston, TX (United States))

    1993-02-01

    Preliminary results of an on-going study of the Cordillera de la Costa belt between Puerto Cabello and Choroni, north-central Venezuela, indicate that the deformational history is far more complicated than expected from simple plate-tectonic models. The Cordillera de la Costa belt consists of oceanic rocks (e.g., serpentinites, amphibilites, with lenses of eclogite and blueschist) intimately intermixed with metamorphosed continental margin deposits (e.g., mica and graphite schist, quartzite, marble). Locally, large granitic (basement ) complexes of Lower Paleozoic age are included as well. In late Cretaceous time, the entire belt was involved in four synmetamorphic deformations phases (D[sub 1a] to D[sub 1d]); the first (D[sub 1a]) occurred at depths of at 35-40 km and the later ones at successively shallower depths. This deformation occurred in a subduction zone, related to right-oblique convergence of the Farallon and Atlantic plates. The most penetrative structures resulted from (all in present coordinates) north-south contraction and east-west dextral simple shear (D[sub 1b]). During an Early Tertiary ( ) event (D[sub 2]), the belt was emplaced southward onto the South American continental margin. Subsequent deformational structures (D[sub 3]) resulted in cross folds and faults (with small pull-apart basins) which are consistent with the eastward passage of the Caribbean past the South American plate.

  13. Green Belt Europe – nature knows no boundaries. From “Iron Curtain” to Europe’s lifeline

    Directory of Open Access Journals (Sweden)

    Liana Geidezis

    2004-01-01

    Full Text Available The “Iron Curtain” divided Europe for almost forty years from the Barents Sea to the Black Sea. It was a political, ideological and physical barrier, most strongly expressed in Germany. Despite its inhumanity, this border granted nature a pause for breath: nature flourished and developed something extremely rare in intensively used landscapes – the so called Green Belt. Since the fall of the Iron Curtain in 1989, a lifeline of habitats about 8.500 km long runs through Europe. It originated from the project Green Belt Germany, initiated by BUND, the vision of a European Green Belt development. It can become a backbone of an ecological network that is a global symbol for trans-boundary co-operation in nature conservation and sustainable development. Moreover, it connects people and shows that the enlarged European Union has not only a cultural but also a natural heritage. The Green Belt is a unique chance to overcome the old boundaries and barriers between East and West – a living symbol of growing together in Europe.

  14. Reservoir-forming age and its exploration significance to stratigraphic reservoirs in southern Songliao Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Despite many studies concerning the forming age, evolution characteristics and the age of petroleum charging in the Fuxin upheaval of southern Songliao Basin, no consensus has been reached so far. This paper presents the first K-Ar dating of autogenetic illite from stratigraphic petroleum reservoirs in the Fuyu oil layer of the Fuxin upheaval belt. Isotopic test and age calculation were carried out based on the separation and purification of illite mineral, X-diffraction analysis and the detection of scanning electron microscopy. The evolution characteristics of structure, sedimentation, reservoir-forming about the Fuxin upheaval belt were interpreted in terms of the synthetical analysis of "six-type geological history" evolution in southern Songliao Basin. The geologic background of petroleum evolution and reservoir formation are similar in the entire central depression region of southern Songliao Basin. The Changling sag and the Fuxin upheaval belt brought about obvious upheaval-sag separation after the hydrocarbon-generation peak of K2qn1 and the main reservoir-forming period of the Fuyu oil layer, namely reservoir-forming happened before the Fuxin upheaval belt extensively raised. The reservoirs have three characteristics: the hydrocarbon source rock above the reservoir, the oil source in the locality, and the vertical migration. The geological cognition is corrected, that is, oil source came from the Changling sag and migrated from the side direction. The bulk process of petroleum charging in the stratigraphic hydrocarbon reservoirs in the Fuxin upheaval belt of southern Songliao Basin is determined according to the isotopic age of autogenetic illite in combination with the method of fluid inclusions. The cognition is helpful to exactly evaluate the resource potential and exploration direction in the Fuxin upheaval belt, Changling sag and their peripheral areas. The present results indicate that the combination of the two methods (the K-Ar dating of

  15. Mineralization features of the granite-type uranium deposits in southern China

    International Nuclear Information System (INIS)

    The present paper deals with the mineralization features of nearly 20 granite-type uranium deposits in Southern China. These features include one in shape of ore bodies, host-rock alteration, mineralogical composition of ore, texture and structure of ore, mineralization type and para-genetic association of mineral. It is shown that the granite-type uranium deposits in Southern China may be situated not only in granite bodies (i.e. inter-belt-type) but also in an exo-contact belts of granite bodies (i.e. exo-belt-type). Shape of ore bodies may be various and is essentially controlled by shape of fracture belts of host-rock and basic veins. Mineralogical compositions of ore are relatively simple. Pitchblende and coffinite are the most important original uranium minerals in this type of uranium deposits. The assemblage of gangue ore-minerals in exo-belt-type uranium deposits is more complex than in inter-belt-type uranium deposits. Most of minerals in ore are fine and show gel texture. The ores of this type of uranium deposits are in form of vein let-dissemination and brecciation. These features suggest that mineralization of the granite-type uranium deposits in Southern China is characterized by low temperature, rapid deposition and shallow ore-source. Kinds of host-rock alteration in this type of uranium deposits are many and varied. The degree of alteration, however, is rather weak. Uranium mineralization in this type of deposits only occurs in certain positions within area of hydrothermal face-type alteration of host rocks. Ore-rich bodies are generally located in the position of strong line-type alteration of host rocks. Various face-type alterations of host rocks which are dispersed in a large limit are an important sign for search after the granite-type uranium deposits in Southern China

  16. Seat belt use during pregnancy in Iran: attitudes and practices

    Institute of Scientific and Technical Information of China (English)

    Mojgan Karbakhsh; Zahra Ershadi; Ali Khaji; Fatemeh Rahimi-Sharbaf

    2010-01-01

    Objective: Seat belt use during pregnancy reduces injury to the mother and her fetus. During recent years, the use of seat belts has been mandated by law in Iran. The purpose of this study was to determine the attitudes and practices of pregnant women regarding seat belt use.Methods: In this cross-sectional study, we asked 335 pregnant women at a hospital-based prenatal care clinic on the use of safety belt before and during pregnancy. SPSS version 13.0 was used for data analysis.Results: The mean age of study subjects was 27.3 years±5.3 years with the median of 27 years. Compared with the seat belt use before pregnancy, no change was detected in 48.7% of the women; seat belt use had increased in 17.5 %of them and decreased in 33.8 %. Eighty-one percent of women knew the correct placing of both lap belt and shoulder belt. Only 4% of women had received education on proper restraint use during pregnancy.Conclusions: The prevalence of seat belt use during pregnancy is lower than reports which are mostly from developed nations. The fact that about one-third of women have decreased their seat belt usage during pregnancy highlights the importance of education of mothers on this topic.

  17. Census Snapshot: West Virginia

    OpenAIRE

    Romero, Adam P; Rosky, Clifford J; Badgett, M. V. Lee; Gates, Gary J.

    2008-01-01

    Using data from the U.S. Census Bureau, this report provides demographic and economic information about same-sex couples and same-sex couples raising children in West Virginia. We compare same-sex “unmarried partners,” which the Census Bureau defines as an unmarried couple who “shares living quarters and has a close personal relationship,” to different-sex married couples in West Virginia. In many ways, the almost 3,500 same-sex couples living in West Virginia are similar to married ...

  18. Minibasins and salt canopy in foreland fold-and-thrust belts: The central Sivas Basin, Turkey

    Science.gov (United States)

    Kergaravat, Charlie; Ribes, Charlotte; Legeay, Etienne; Callot, Jean-Paul; Kavak, Kaan Sevki; Ringenbach, Jean-Claude

    2016-06-01

    The Sivas Basin in the Central Anatolian Plateau (Turkey), which formed in the context of a foreland fold-and-thrust belt (FTB), exhibits a typical wall and basin (WAB) province characterized by symmetric minibasins separated by continuous steep-flanked walls and diapirs. Extensive fieldwork including regional and detailed local mapping of the contacts and margins of minibasins, and interpretation of a set of 2-D regional seismic lines, provide evidence for the development of a shallow evaporite level separating two generations of minibasins within the WAB province. Here beds of symmetric exposed minibasins along diapir flank are younger than minibasins observed over autochthonous evaporites. Laterally away from the WAB province, increase in wavelength of the tectonic structures suggests a deepening of the decollement level. We interpret that a shallower evaporite level developed in the form of an evaporite canopy, triggered by significant lateral shortening. The Upper Eocene-Lower Oligocene autochthonous Tuzhisar evaporite level was remobilized by the northward migrating sedimentary load and the tilting of the southern basin margin during propagation of the foreland fold-and-thrust belt. Asymmetric and symmetric primary minibasins were overrun by an allochthonous sheet forming a canopy. A second generation of salt withdrawal minibasins subsided into the allochthonous salt sheet. The polygonal pattern of the WAB province influences the growing fold-and-thrust belt system during the late stage of the secondary minibasins development. The Sivas FTB basin is the result of the interaction between fold-and-thrust belt propagation, evaporite remobilization, and interaction between evaporite flow and sedimentation in the minibasins.

  19. Fault-related fold styles and progressions in fold-thrust belts: Insights from sandbox modeling

    Science.gov (United States)

    Yan, Dan-Ping; Xu, Yan-Bo; Dong, Zhou-Bin; Qiu, Liang; Zhang, Sen; Wells, Michael

    2016-03-01

    Fault-related folds of variable structural styles and assemblages commonly coexist in orogenic belts with competent-incompetent interlayered sequences. Despite their commonality, the kinematic evolution of these structural styles and assemblages are often loosely constrained because multiple solutions exist in their structural progression during tectonic restoration. We use a sandbox modeling instrument with a particle image velocimetry monitor to test four designed sandbox models with multilayer competent-incompetent materials. Test results reveal that decollement folds initiate along selected incompetent layers with decreasing velocity difference and constant vorticity difference between the hanging wall and footwall of the initial fault tips. The decollement folds are progressively converted to fault-propagation folds and fault-bend folds through development of fault ramps breaking across competent layers and are followed by propagation into fault flats within an upper incompetent layer. Thick-skinned thrust is produced by initiating a decollement fault within the metamorphic basement. Progressive thrusting and uplifting of the thick-skinned thrust trigger initiation of the uppermost incompetent decollement with formation of a decollement fold and subsequent converting to fault-propagation and fault-bend folds, which combine together to form imbricate thrust. Breakouts at the base of the early formed fault ramps along the lowest incompetent layers, which may correspond to basement-cover contacts, domes the upmost decollement and imbricate thrusts to form passive roof duplexes and constitute the thin-skinned thrust belt. Structural styles and assemblages in each of tectonic stages are similar to that in the representative orogenic belts in the South China, Southern Appalachians, and Alpine orogenic belts.

  20. Paleo-Tethyan evolution of Tibet as recorded in the East Cimmerides and West Cathaysides

    Science.gov (United States)

    Xu, Zhiqin; Dilek, Yildirim; Cao, Hui; Yang, Jingsui; Robinson, Paul; Ma, Changqian; Li, Huaqi; Jolivet, Marc; Roger, Françoise; Chen, Xijie

    2015-06-01

    The Paleozoic-early Mesozoic geology of Tibet was controlled by the rift-drift, seafloor spreading and subduction zone tectonics of a Paleo-Tethyan realm, which evolved between the West Cathaysides (WC) and the East Cimmerides (EC). Different suture zones with ophiolites and ophiolitic mélanges, high-pressure metamorphic belts, magmatic arcs and accretionary prism complexes separating different terranes mark multiple subduction-accretion systems within this Paleo-Tethyan domain, reminiscent of the modern Western Pacific Ocean. Discrete basins separated by different continental blocks and magmatic arcs constituted a complex paleogeography of Paleo-Tethys, and these oceanic strands were closed as a result of subduction with different polarities during the late Paleozoic-Triassic. The Longmu Tso Shuanghu-Changning Menglian Suture zone (LS-CMS) in Tibet represents the main tectonic boundary between the WC and EC that developed in the Devonian. The East Kunlun-A'nyemaqen oceanic slab was subducted northward beneath the East Kunlun terrane in northern Tibet, whereas the Sumdo oceanic slab was subducted northward beneath the South Qiangtang-North Lhasa terrane in southern Tibet. The Longmu Tso Shuanghu-Changning Menglian and Jinshajiang-Ailaoshan-Song Ma ophiolites were developed and emplaced in subduction-accretion systems with opposite polarities (westward and eastward) beneath the North Qiangtang-Qamdo-Simao-Indochina terrane in central Tibet. The Jinshajiang-Ailaoshan-Song Ma oceanic slab was subducted westward beneath the North Qiangtang-Simao-Indochina terrane along the Jinshajiang and Ailaoshan-Song Ma trenches in a trench-ridge-trench triple junction plate configuration. The Emeishan mantle plume produced a large Permian basaltic terrane, developed on the western passive margin of the South China block. The final closure of the Paleo-Tethyan oceanic branches resulted in continental collisions and development of a vast Indosinian orogenic collage in the latest

  1. The Neoproterozoic-Cambrian Paraguay Belt, central Brazil: Part I - New structural data and a new approach on the regional implications

    Science.gov (United States)

    Silva, Luiz José Homem D'el-Rey; Walde, Detlef Hans-Gerd; Saldanha, Davi Oliveira

    2016-04-01

    Together with the Araguaia and Brasília belts, the Paraguay belt forms in central Brazil, the Tocantins Province that is one of the largest orogens of western Gondwana. The Corumbá area occupies the site where the northern and southern parts of the Paraguay belt form, together with the Chiquitos-Tucavaca aulacogen (stretching E-W in the adjacent Bolivian territory) an R-R-R basin system opened-filled in the ~ 700/650-540 Ma interval within the Amazon-Rio Apa paleo-continent. The sedimentary (volcanic) rocks of the Jacadigo and Corumbá Groups found around the Corumbá city record part of the Neoproterozoic-Cambrian passive margin precursor of the Paraguay belt. Our pioneer structural analysis reveals that these rocks experienced progressive deformation (phases D1-D2-D3) and low-grade metamorphism during the Brasiliano Cycle (540-513 Ma). The crystalline basement was also involved, according to structural data and K-Ar ages in the literature. The paleo-passive margin was thickened during the D1-D2 deformation and was lately shortened (D3) in two orthogonal directions, SE-NW (D3P) and SW-NE (D3T). Developed co-axially and verging to NW, D1-D2-D3P structures record the closure of the basin precursor of the Paraguay belt, whereas D3T structures seem related to the inversion of the aulacogen. Although the tectonic transport to NW, as observed in the Corumbá area, matches the reported transport of Paraguay belt's supracrustal rocks towards the eastern margin of the Rio Apa block and Araguaia belt's rocks towards the Amazon craton, the transport direction is opposite in other parts of the Paraguay belt. Our comprehensive discussion of these facts brings to light profound regional implications.

  2. Charnockitic magmatism in southern India

    Science.gov (United States)

    Rajesh, H. M.; Santosh, M.

    2004-12-01

    Large charnockite massifs cover a substantial portion of the southern Indian granulite terrain. The older (late Archaean to early Proterozoic) charnockites occur in the northern part and the younger (late Proterozoic) charnockites occur in the southern part of this high-grade terrain. Among these, the older Biligirirangan hill, Shevroy hill and Nilgiri hill massifs are intermediate charnockites, with Pallavaram massif consisting dominantly of felsic charnockites. The charnockite massifs from northern Kerala and Cardamom hill show spatial association of intermediate and felsic charnockites, with the youngest Nagercoil massif consisting of felsic charnockites. Their igneous parentage is evident from a combination of features including field relations, mineralogy, petrography, thermobarometry, as well as distinct chemical features. The southern Indian charnockite massifs show similarity with high-Ba-Sr granitoids, with the tonalitic intermediate charnockites showing similarity with high-Ba-Sr granitoids with low K2O/Na2O ratios, and the felsic charnockites showing similarity with high-Ba-Sr granitoids with high K2O/Na2O ratios. A two-stage model is suggested for the formation of these charnockites. During the first stage there was a period of basalt underplating, with the ponding of alkaline mafic magmas. Partial melting of this mafic lower crust formed the charnockitic magmas. Here emplacement of basalt with low water content would lead to dehydration melting of the lower crust forming intermediate charnockites. Conversely, emplacement of hydrous basalt would result in melting at higher {ie565-01} favoring production of more siliceous felsic charnockites. This model is correlated with two crustal thickening phases in southern India, one related to the accretion of the older crustal blocks on to the Archaean craton to the north and the other probably related to the collision between crustal fragments of East and West Gondwana in a supercontinent framework.

  3. Charnockitic magmatism in southern India

    Indian Academy of Sciences (India)

    H M Rajesh; M Santosh

    2004-12-01

    Large charnockite massifs cover a substantial portion of the southern Indian granulite terrain. The older (late Archaean to early Proterozoic) charnockites occur in the northern part and the younger (late Proterozoic) charnockites occur in the southern part of this high-grade terrain. Among these, the older Biligirirangan hill, Shevroy hill and Nilgiri hill massifs are intermediate charnockites, with Pallavaram massif consisting dominantly of felsic charnockites. The charnockite massifs from northern Kerala and Cardamom hill show spatial association of intermediate and felsic charnockites, with the youngest Nagercoil massif consisting of felsic charnockites. Their igneous parentage is evident from a combination of features including field relations, mineralogy, petrography, thermobarometry, as well as distinct chemical features. The southern Indian charnockite massifs show similarity with high-Ba–Sr granitoids, with the tonalitic intermediate charnockites showing similarity with high-Ba–Sr granitoids with low K2O/Na2 ratios, and the felsic charnockites showing similarity with high-Ba–Sr granitoids with high K2O/Na2O ratios. A two-stage model is suggested for the formation of these charnockites. During the first stage there was a period of basalt underplating, with the ponding of alkaline mafic magmas. Partial melting of this mafic lower crust formed the charnockitic magmas. Here emplacement of basalt with low water content would lead to dehydration melting of the lower crust forming intermediate charnockites. Conversely, emplacement of hydrous basalt would result in melting at higher fH2O favoring production of more siliceous felsic charnockites. This model is correlated with two crustal thickening phases in southern India, one related to the accretion of the older crustal blocks on to the Archaean craton to the north and the other probably related to the collision between crustal fragments of East and West Gondwana in a supercontinent framework.

  4. US west coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aerial surveys are conducted along the US west coast to determine distribution and abundance of endangered leatherback turtles (Dermochelys coriacea), loggerhead...

  5. Tectonic Subdivision of Dabie Orogenic Belt, Central China: Evidence from Pb Isotope Geochemistry of Late Mesozoic Basalts

    Institute of Scientific and Technical Information of China (English)

    匡少平; 张本仁

    2002-01-01

    It has long been debated that the Dabie orogenic belt belongs to the North China or Yangtze craton. In recent years, eastern China has been suggested, based on the Pb isotopic compositions of Phanerozoic ore and Mesozoic granitoid K-feldspar (revealing the crust Pb) in combination with Meso-Cenozoic basalts (revealing the mantle Pb), being divided into the North China and Yangtze Pb isotopic provinces, where the crust and mantle of the Yangtze craton are characterized by more radiogenic Pb. In this sense, previous researchers suggested that the pro-EW-trending Dabie orogenic belt with less radiogenic Pb in the crust was part of the North China craton. In this paper, however, the Late Cretaceous basalts in the central and southern parts of the Dabie orogenic belt are characterized by some more radiogenic Pb (206pb/204pb = 17. 936 - 18. 349, 207pb/204pb = 15. 500 - 15. 688, 208pb/204pb = 38. 399 - 38. 775 )and a unique U-Th-Pb trace element system similar to those of the Yangtze craton, showing that the Mesozoic mantle is of the Yangtze type. In addition, the decoupled Pb isotopic compositions between crust and mantle were considerably derived from their rheological inhomogeneity, implying a complicated evolution of the Dabie orogenic belt.

  6. 40Ar/39Ar ages of granitoids from the Truong Son fold belt and Kontum massif in Laos

    International Nuclear Information System (INIS)

    Geochemical and geochronological studies were conducted on granitoids in central-southern Laos. S-type ilmenite-series granitoids associated with Sn mineralization are distributed in the Truong Son fold belt of central Laos. Plateau ages determined by 40Ar/39Ar incremental heating method for biotite and muscovite of the granitoids range from 253 Ma to 247 Ma and from 244 Ma to 199 Ma in the southwest and northeast of the fold belt, respectively. During this period, the fractionated granites in the early stage are related to mineralization of medium-large Sn deposits. The granitoids of the Truong Son fold belt formed in the Indosinian orogeny are contemporaneous with the Late Permian-Early Jurassic Sn-bearing granites in the Southeast Asian Sn Belt. In contrast, I-type magnetite-series granitoids are distributed in the Kontum massif of southeasternmost Laos. Plateau ages for biotite and previously reported mineral ages of the magnetite-series granitoids range widely from 414 Ma to 252 Ma. The Carboniferous-Permian granitoids represents adakitic characteristics and the Permian adakitic granodiorites are associated with Cu ± Au mineralized quartz veins. (author)

  7. Study provides new evidence of back belts' effectiveness.

    Science.gov (United States)

    McIntyre, D R; Bolte, K M; Pope, M H

    1996-12-01

    A major new study conducted by the UCLA School of Public Health has bolstered the claim that back support devices reduce low-back injuries. The study involved nearly 36,000 employees at Home Depot stores in California who logged 101 million work hours from 1989 through 1994. The company implemented mandatory wearing of belts in early 1990, and the study's authors reported that the workers' rate of acute low back injuries fell from 30.6 per million hours before implementation to 20.2 per million hours. UCLA Professor of Epidemiology Jess F. Kraus, the study's lead author, told The Wall Street Journal. "The study found a pretty big effect with a simple countermeasure. It is pretty hard to argue that it is a chance phenomenon." Kraus, who is the director of UCLA's Southern California injury Prevention Research Center, began his research by visiting 30 Home Depot stores to see whether employees were wearing the belts consistently. Compliance with the mandatory policy was quite high overall-above 98 percent, as calculated during an unannounced walk-through of all 77 stores in late 1993 and early 1994, according to the study. Back support manufactures hailed the Home Depot study as the largest long-term epidemiological study yet undertaken of the supports. It is proof, they said, that back supports are effective personal protective equipment-a contention at odds with the position of NIOSH the National institute for Occupational Safety and Health. In 1994, NIOSH reviewed the scientific literature and concluded there was not enough evidence to recommend that the supports be worn by uninjured workers. Sales plunged after NIOSH released its findings, according to the manufactures. The UCLA researchers found that low-back injuries declined in workers of both sexes, in younger workers as well as those older than 55, and among those with low levels of lifting as well as those with higher levels. The researchers concluded that mandatory use of back supports significantly reduces

  8. Health Monitoring for Coated Steel Belts in an Elevator System

    OpenAIRE

    Yimei Mao; Zuoying Huang; Guiyun Tian; Hui Zhao; Huaming Lei

    2012-01-01

    This paper presents a method of health monitoring for coated steel belts in an elevator system by measuring the electrical resistance of the ropes embedded in the belt. A model on resistance change caused by fretting wear and stress fatigue has been established. Temperature and reciprocating cycles are also taken into consideration when determining the potential strength degradation of the belts. It is proved by experiments that the method could effectively estimate the health degradation of ...

  9. Device for continuous tare measurement at belt weighers

    International Nuclear Information System (INIS)

    The described device can be used for belt weighers connected with a computing unit. Its development has been aimed at measuring the weight of the belt without standstill. This could be achieved by arranging radiation sources and detectors over the whole width of the belt and transforming the radiation attenuation into weight equivalents with the aid of an evaluation unit connected to the computing unit

  10. The relation of the mid-Tertiary coastal magmatic belt in south-central Chile to the late Oligocene increase in plate convergence rate

    OpenAIRE

    Jorge Muñoz; Rosa Troncoso; Paul Duhart; Pedro Crignola; Lang Farmer; Charles R. Stern

    2000-01-01

    The mid-Tertiary Coastal Magmatic Belt in south-central Chile, which crops out both in the Central Valley and, south of 41°S, in the Coastal Cordillera as far west as the Pacific coast, formed when the locus of Andean magmatic activity expanded, both to the west and to the east relative to its previous and current location in the Main Cordillera. This expansion of the magmatic arc occurred in conjunction with a regionally widespread episode of late Oligocene to Miocene extension which thinned...

  11. Car safety belts: a study of two models adapted for people with arthritis.

    Science.gov (United States)

    Arie, E

    1986-05-01

    People with arthritis find car seat belts difficult to use. Sixteen arthritic patients and 19 healthy volunteers completed a comparative study of one standard inertia-reel belt and two adapted inertia-reel belts with reduced retraction forces. Those with arthritis were strong enough to use the standard belt but both adapted belts had features making them easier to use. PMID:3708235

  12. Rirang Uranium Ore Processing System Design Horizontal Belt Filter

    International Nuclear Information System (INIS)

    Horizontal belt filter one of the solid-liquid separation process equipment. The design of Horizontal Belt Filter have been conducted for capacity of 250 g/minute. The result obtained was filtering velocity of 0,4 g/cm2 minute. The linear belt speeds 100 cm/minute. The length and width of the belt 125 cm also the filtering cycle of 1,25 minute. The operation of that equipment give result about 77,9 - 79,1% of product cake

  13. Health Monitoring for Coated Steel Belts in an Elevator System

    Directory of Open Access Journals (Sweden)

    Huaming Lei

    2012-01-01

    Full Text Available This paper presents a method of health monitoring for coated steel belts in an elevator system by measuring the electrical resistance of the ropes embedded in the belt. A model on resistance change caused by fretting wear and stress fatigue has been established. Temperature and reciprocating cycles are also taken into consideration when determining the potential strength degradation of the belts. It is proved by experiments that the method could effectively estimate the health degradation of the most dangerous section as well as other ones along the whole belts.

  14. Predicting Facies Patterns within Fluvial Channel Belts

    Science.gov (United States)

    Willis, B. J.; Sech, R.; Sun, T.; Pyrcz, M.

    2014-12-01

    Reservoirs (aquifers) in fluvial channel belt sandstones can have very different subsurface flow behavior depending on the degree and distribution of internal heterogeneities. Fluvial channel belts are composed of multiple "storeys" formed as individual channel segments increase in sinuosity and then are cut off and abandoned. Heterogeneities are defined by depositional variations across storeys and inter-story connectivity patterns along the channel belt. Although commonly inferred to reflect the formative river pattern (sinuosity & braiding), the spatial arrangement of facies depend most directly on the relative preservation of deposits formed within different areas of the migrating channels and the lateral stacking arrangement of storeys due to style of bend cutoff. Grains are poorly sorted across the inner bank along upstream parts of channel bends and become better sorted laterally in downstream areas adjacent to a deeper thalweg scour. If deposition occurs evenly along the entire inner bank (bar), this grain size pattern leads to an elliptical body in planview with weak vertical grain size trends upstream and more fining-upward trend downstream. As channel bend segments migrate to a greater extent downstream, preserved inner-bank-bar deposits are increasingly dominated by upward-fining deposits and more outer-bank-deposits are preserved ("concave bank" deposits). Although concave bank deposits have highly variable character in different systems, vertical-grainsize trends tend to be weaker in straighter systems dominated by downstream-accretion, and more strongly upward-fining in higher sinuosity systems where these deposits form by eddy accretion or low flow aggradation. River cutoffs of straighter channel segments abandon slowly, leading to more gradual vertical fining. Subsurface heterogeneity prediction requires documentation of shape and character of deposits preserved in different zones within the channel (upstream and downstream inner bank, concave bank

  15. Terrestrial heat flow in east and southern Africa

    Science.gov (United States)

    Nyblade, Andrew A.; Pollack, Henry N.; Jones, D. L.; Podmore, Francis; Mushayandebvu, Martin

    1990-10-01

    We report 26 new heat flow and 13 radiogenic heat production measurements from Zimbabwe, Zambia and Tanzania, together with details and some revisions of 18 previous heat flow measurements by other investigators from Kenya and Tanzania. These measurements come from Archean cratons, Proterozoic mobile belts, and Mesozoic and Cenozoic rifts. Heat flow data from eight new sites in the Archean Zimbabwe Craton are consistent with previous measurements in the Archean Kaapvaal-Zimbabwe Craton and Limpopo Belt (Kalahari Craton) and do not change the mean heat flow of 47±2 mW m-2 (standard error of the mean) in the Kalahari Craton based on 53 previous measurements. Eight new sites in the Archean Tanzania Craton give a mean heat flow of 34±4 mW m-2. The mean heat flow from nine sites in the Proterozoic Mozambique Belt to the east of the Tanzania Craton in Kenya and Tanzania is 47±4 mW m-2. Twelve measurements in the Mesozoic rifted continental margin in east Africa give a mean heat flow of 68±4 mW m-2; four measurements in the Mesozoic Luangwa and Zambezi Rifts range from 44 to 110 mW m-2 with a mean of 76±14 mW m-2. In comparing heat flow in east and southern Africa, we observe a common heat flow pattern of increasing heat flow away from the centers of the Archean cratons. This pattern suggests a fundamental difference in lithospheric thermal structure between the Archean cratons and the Proterozoic and early Paleozoic mobile belts which surround them. Superimposed on this common pattern are two regional variations in heat flow. Heat flow in the Tanzania Craton is lower by about 13 mW m-2 than in the Kalahari Craton, and in the Mozambique Belt in east Africa heat flow is somewhat lower than in the southern African mobile belts at similar distances from the Archean cratonic margin. The two regional variations can be explained in several ways, none of which can as yet be elevated to a preferred status: (1) by variations in crustal heat production, (2) by thin

  16. Energy in corn belt crop production

    Energy Technology Data Exchange (ETDEWEB)

    Lockeretz, W.; Klepper, R.; Gertler, M.; Fast, S.; O' Leary, D.

    1975-07-01

    The study presents data on the quantity and cost of the energy used to produce corn, soybeans, and wheat in the western part of the Corn Belt in 1974. The analysis covers fuel for field equipment, energy required to manufacture fertilizers and pesticides, and energy for drying corn. Corn is the most energy-intensive of the three crops studied, with soybeans the lowest. The cost of energy for crop production amounts to 11%, 8%, and 6% of the overall direct production costs for corn, wheat, and soybeans, respectively. These energy costs come to less than 3% of the value of the crop in all three cases. (GRA)

  17. Meningococcal carriage in the African meningitis belt

    OpenAIRE

    2013-01-01

    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent ...

  18. Parametric resonances of convection belt system

    Institute of Scientific and Technical Information of China (English)

    Zhi-an YANG; Gao-feng LI

    2009-01-01

    Based on the Coriolis acceleration and the Lagrangian strain formula,a generalized equation for the transverse vibration system of convection belts is derived using Newton's second law.The method of multiple scales is directly applied to the governing equations,and an approximate solution of the primary parameter resonance of the system is obtained.The detuning parameter,cross-section area,elastic and viscoelastic parameters,and axial moving speed have a significant influences on the amplitudes of steady-state response and their existence boundaries.Some new dynamical phenomena are revealed.

  19. Two stages of deformation and fluid migration in the central Brooks Range fold-and-thrust belt

    Science.gov (United States)

    Moore, Thomas E.; Potter, Christopher J.; O'Sullivan, Paul B.; Shelton, Kevin L.; Underwood, Michael B.

    2004-01-01

    The Brooks Range is a north-directed fold and thrust belt that forms the southern boundary of the North Slope petroleum province in northern Alaska. Field-based studies have long recognized that large-magnitude, thin-skinned folding and thrusting in the Brooks Range occurred during arc-continent collision in the Middle Jurassic to Early Cretaceous (Neocomian). Folds and thrusts, however, also deform middle and Upper Cretaceous strata of the Colville foreland basin and thus record a younger phase of deformation that apatite fission-track data have shown to occur primarily during the early Tertiary (~60 and ~45 Ma). A structural and kinematic model that reconciles these observations is critical to understanding the petroleum system of the Brooks Range fold and thrust belt.

  20. The relationship between continental collision process and metamorphic pattern in the Himalayan collision belts

    Science.gov (United States)

    Oh, Chang-Whan

    2015-04-01

    Both UHP and HP eclogites are reported from the Kaghan Valley and Tso Morari Massif in the western part of the Himalayan collision belt (Ghazanfar and Chaudhry, 1987; Thakur, 1983). UHP eclogites in the Kaghan record peak metamorphic conditions of 770 °C and 30 kbar (O'Brien et al., 2001) and was retrograded into the epidote-amphibolite or blueschist (580-610 °C, 10-13 kbar; Lombardo and Rolfo, 2000). Sensitive high-resolution ion microprobe dating of zircon reveals that the UHP eclogite formed at ca. 46 Ma (Kaneko et al., 2003; Parrish et al., 2006). The Tso Morari UHP eclogite had formed at 750 °C, > 39 kbar (Mukheerjee et al., 2003; Bundy, 1980) and underwent amphibolite facies retro-grade metamorphism (580 °C, 11 kbar) during uplift (Guillot et al., 2008). Peak metamorphism of the Tso Morari Massif was dated at ca. 53-55 Ma (Leech et al., 2005). Only HP eclogites have been reported from the mid-eastern part of the Himalayan collision belt (Lombardo and Rolfo, 2000; Corrie et al., 2010). The HP eclogite in the mid-eastern part may have formed at ca. > 780 °C and 20 kbar and was overprinted by high-pressure granulite facies metamorphism (780-750°C, 12-10 kbar) at ca. 30 Ma (Groppo et al. 2007; Corrie et al., 2010). HP granulite (890 °C, 17-18 kbar) is reported from the NBS, at the eastern terminus of the Himalayan collision belt; the granulite was subjected to retrograde metamorphism to produce lower-pressure granulite (875-850°C, 10-5 kbar), representing near-isothermal decompression (Liu and Zhong, 1997). The HP granulite metamorphism may have occurred at ca. 22-25 Ma. Along the Himalayan collision belt, peak metamorphism changes eastward from UHP eclogite facies through HP eclogite facies to high-pressure granulite facies, indicating a progressive eastwards decrease in the depth of subduction of continental crust and an eastwards increase in the geothermal gradient. The peak metamorphic ages also decrease from 53-46 Ma in the west to 22-25 Ma in the

  1. The ARM West Antarctic Radiation Experiment (AWARE)

    Science.gov (United States)

    Lubin, Dan; Bromwich, David; Vogelmann, Andrew; Verlinde, Johannes; Russell, Lynn

    2016-04-01

    West Antarctica is one of the most rapidly warming regions on Earth, and its changing climate in both atmosphere and ocean is linked to loss of Antarctic ice mass and global sea level rise. The specific mechanisms for West Antarctic Ice Sheet (WAIS) warming are not fully understood, but are hypothesized to involve linkage between moisture from Southern Ocean storm tracks and the surface energy balance over the WAIS, and related teleconnections with subtropical and tropical meteorology. This present lack of understanding has motivated a climate science and cloud physics campaign jointly supported by the US National Science Foundation (NSF) and Department of Energy (DOE), called the Atmospheric Radiation Measurement Program (ARM) West Antarctic Radiation Experiment (AWARE). The DOE's second ARM Mobile Facility (AMF2) was deployed to McMurdo Station on Ross Island in November 2015 and will operate through December 2016. The AMF2 includes (1) cloud research radars, both scanning and zenith, operating in the Ka- and X-bands, (2) high spectral resolution and polarized micropulse lidars, and (3) a suite of shortwave and longwave broadband and spectral radiometers. A second suite of instruments is deployed at the WAIS Divide Ice Camp on the West Antarctic plateau during December 2015 and January 2016. The WAIS instrument suite provides (1) measurement of all surface energy balance components, (2) a polarized micropulse lidar and shortwave spectroradiometer, (3) microwave total water column measurement, and (4) four times daily rawinsonde launches which are the first from West Antarctica since 1967. There is a direct linkage between the WAIS instrument suite and the AMF2 at McMurdo, in that air masses originating in Southern Ocean storm tracks that are driven up over the WAIS often subsequently descend over the Ross Ice Shelf and arrive at Ross Island. Preliminary data are already illustrating the prevalence of mixed-phase clouds and their role in the surface energy balance

  2. Fading of Jupiter's South Equatorial Belt

    Science.gov (United States)

    Sola, Michael A.; Orton, Glenn; Baines, Kevin; Yanamandra-Fisher, Padma

    2011-01-01

    One of Jupiter's most dominant features, the South Equatorial Belt, has historically gone through a "fading" cycle. The usual dark, brownish clouds turn white, and after a period of time, the region returns to its normal color. Understanding this phenomenon, the latest occurring in 2010, will increase our knowledge of planetary atmospheres. Using the near infrared camera, NSFCAM2, at NASA's Infrared Telescope Facility in Hawaii, images were taken of Jupiter accompanied by data describing the circumstances of each observation. These images are then processed and reduced through an IDL program. By scanning the central meridian of the planet, graphs were produced plotting the average values across the central meridian, which are used to find variations in the region of interest. Calculations using Albert4, a FORTRAN program that calculates the upwelling reflected sunlight from a designated cloud model, can be used to determine the effects of a model atmosphere due to various absorption, scattering, and emission processes. Spectra that were produced show ammonia bands in the South Equatorial Belt. So far, we can deduce from this information that an upwelling of ammonia particles caused a cloud layer to cover up the region. Further investigations using Albert4 and other models will help us to constrain better the chemical make up of the cloud and its location in the atmosphere.

  3. The Dynamical Evolution of the Asteroid Belt

    CERN Document Server

    Morbidelli, Alessandro; O'Brien, David P; Minton, David A; Bottke, William F

    2015-01-01

    The asteroid belt is the leftover of the original planetesimal population in the inner solar system. However, currently the asteroids have orbits with all possible values of eccentricities and inclinations compatible with long-term dynamical stability, whereas the initial planetesimal orbits should have been quasi-circular and almost co-planar. The total mass in the asteroid population is a small fraction of that existing primordially. Also, asteroids with different chemical/mineralogical properties are not ranked in an orderly manner with mean heliocentric distance as one could expect from the existence of a radial gradient of the temperature in the proto-planetary disk, but they are partially mixed. These properties show that the asteroid belt has been severely sculpted by one or a series of processes during its lifetime. This paper reviews the processes that have been proposed so far, discussing the properties that they explain and the problems that they are confronted with. Emphasis is paid to the interpl...

  4. Stabilization of electrostatic accelerator charging belt current

    International Nuclear Information System (INIS)

    For the purpose of improving reliability and quality of electrostatic accelerator basic parameters the stabilizer of charging belt current is developed. The stabilizer consists of two units: high-voltage unit and control unit. The charging rectifier assures voltage up to 60 kV at total current load of 750 μA. For the EG- 2.5 and the EGP-10 M accelerators supply circuits of charging device with an earth screen and posAitive voltage supply the needles. t the EGP-10-1 accelerator negative charging voltage is supplied to the screens of the charging device. ''Plus'' of the rectifier is earthed. Charging and recharging are performed by means of brushes slipping over the internal belt side. At all accelerators the stability of charging current mean value is not worse 0.1%. The highest response of the system are obtained at the EG-2.5 accelerator for account of rectifier load by charging current and instrument resistor from 140 to 400 MOhm

  5. Islam and the West

    Directory of Open Access Journals (Sweden)

    Mohd. Kamal Hassan

    1997-06-01

    Full Text Available The scientific and technological developments during the 18th and' the 19th centuries ensured material progress of the West, as well as emergence of the West as the dominating power which colonized the rest of the world. During the post-colonial phase, Islam emerged as a revitalized sociopolitical force. This has been mistaken as a threat by the West, and Islam has been portrayed as the "new enemy after the demise of communism. This is partly an effort to establish a Western identity, which is disintegrating due to lack of a challenge; and partly a reflection of the failure of Muslims to realize the social and ethical ideals of Islam.

  6. 30 CFR 57.4263 - Underground belt conveyors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Underground belt conveyors. 57.4263 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Firefighting Equipment § 57.4263 Underground belt conveyors. Fire protection shall...

  7. Safety belt usage in Finland and in other Nordic countries.

    NARCIS (Netherlands)

    Valtonen, J.

    1992-01-01

    Legislation has played a significant role in increasing safety belt usage in Finland and in the other Nordic countries. Publicity and enforcement have, however, been required to support the legislation. The development of safety belt regulations has been nearly similar in all these countries, both i

  8. Canadian seat belt wearing rates, promotion programs, and future directions.

    NARCIS (Netherlands)

    Grant, B.A.

    1992-01-01

    On the basis of a national driver seat belt survey conducted in Canada each year, the most important results are presented. A number of programmes for increasing seat belt use has been evaluated in Canada. Finally, a description is given of some of the current and planned activities within Canada wh

  9. Respiratory Belt Transducer Constructed Using a Singing Greeting Card Beeper

    Science.gov (United States)

    Bhaskar, Anand; Subramani, Selvam; Ojha, Rajdeep

    2013-01-01

    An article by Belusic and Zupancic described the construction of a finger pulse sensor using a singing greeting card beeper. These authors felt that this beeper made of piezoelectric material could be easily modified to function as a respiratory belt transducer to monitor respiratory movements. Commercially available respiratory belt transducers,…

  10. A belt charging system for the Vivitron - design, early results

    International Nuclear Information System (INIS)

    A specific belt charging system has been designed, built and assembled for the 35 MV Vivitron. 100 m long belt is used. Together with main features of the design, experimental studies, tests in a pilot machine and the results of the very early tests of the real system are reviewed

  11. Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province

    Science.gov (United States)

    Helmstaedt, H.; Padgham, W. A.

    The Yellowknife greenstone belt is the western margin of an Archean turbidite-filled basin bordered on the east by the Cameron River and Beaulieu River volcanic belts (Henderson, 1981; Lambert, 1982). This model implies that rifting was entirely ensialic and did not proceed beyond the graben stage. Volcanism is assumed to have been restricted to the boundary faults, and the basin was floored by a downfaulted granitic basement. On the other hand, the enormous thickness of submarine volcanic rocks and the presence of a spreading complex at the base of the Kam Group suggest that volcanic rocks were much more widespread than indicated by their present distribution. Rather than resembling volcanic sequences in intracratonic graben structures, the Kam Group and its tectonic setting within the Yellowknife greenstone belt have greater affinities to the Rocas Verdes of southern Chile, Mesozoic ophiolites, that were formed in an arc-related marginal basin setting. The similarities of these ophiolites with some Archean volcanic sequences was previously recognized, and served as basis for their marginal-basin model of greenstone belts. The discovery of a multiple and sheeted dike complex in the Kam Group confirms that features typical of Phanerozoic ophiolites are indeed preserved in some greenstone belts and provides further field evidence in support of such a model.

  12. Experimental Measurements of Belt Gears in Newly Developed Device

    Directory of Open Access Journals (Sweden)

    Jozef Mascenik

    2016-05-01

    Full Text Available The paper deals with the alternative of determination of state of the belt gear. To realize themeasurements a newly developed device was designed for measurement and diagnostics of the belt gears. The main task is to detect the V-belt slip expressed by the coefficient of elastic creep and of specific slip with a measuring device. The measurements regarding can be performed if input revolutions of the electric motor and torque of the belt gear are constant whereas the tensioning force of the belt gear changes. It is also possible to perform the measurement if the input revolutions of the electric motor and the tensioning forces are constant and the torque changes.

  13. Traffic restrictions due to wind on the Fehmarn Belt bridge

    DEFF Research Database (Denmark)

    Dellwik, E.; Mann, Jakob; Rosenhagen, G.

    2006-01-01

    same as used in this report and here the comparison is satisfactory. We estimate that the prospective Fehmarn Belt bridge will be closed roughly 2% of the timefor light roadway vehicles (unloaded trucks and caravans), corresponding to 7 days per year. This is slightly less than for the Fehmarnsund...... Bridge. For the Great Belt bridge the corresponding actual fraction is 1.5%, despite the fact that this bridge usesstricter criteria. The most important difference between the bridges in this connection is their orientation with respect to the prevailing wind direction. If all the large bridges (Øresund......, Great Belt and Fehmarn Belt) used the same criteria the FehmarnBelt bridge would be closed approximately twice as much as the two others. The majority of these restrictions are likely to take place in the winter time and can be significantly reduced with wind screens....

  14. Petrology and geochemistry of metamorphosed komatiites and basalts from the Sula Mountains greenstone belt, Sierra Leone

    Science.gov (United States)

    Rollinson, Hugh

    The Sula Mountains greenstone belt is the largest of the late-Archaean greenstone belts in the West African Craton. It comprises a thick (5km) lower volcanic formation and a thinner (2km) upper metasedimentary formation. Komatiites and basalts dominate the volcanic formation and komatiites form almost half of the succession. All the volcanic rocks are metamorphosed to amphibolite grade and have been significantly chemically altered. Two stages of alteration are recognised and are tentatively ascribed to hydrothermal alteration and later regional amphibolite facies metamorphism. Ratios of immobile trace elements and REE patterns preserve, for the most part, original igneous signatures and these are used to identify five magma types. These are: low-Ti komatiites - depleted in light REE; low-Ti komatiites - with flat REE patterns; high-Ti komatiitic basalts - with flat REE; low-Ti basalts - depleted in light REE; high-Ti basalts - with flat REE patterns. Much of the variation between the magma types can be explained in terms of different melt fractions of the mantle source, although there were two separate mantle sources one light REE depleted, the other not. The interleaving of the basalts and komatiites produced by this melting indicates that the two mantle sources were melted simultaneously. The simplest model with which to explain these complex melting processes is during melting within a rising mantle plume in which there were two different mantle compositions. The very high proportion of komatiites in the Sula Mountains relative to other greenstone belts suggests either extensive deep melting and/or the absence of a thick pre-existing crust which would have acted as a ``filter'' to komatiite eruption.

  15. A Study on the Vibration of the Charging Belt in an Electrostatic Accelerator

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The vibration of the charging belt in an electrostatic accelerator has intense influences on the accelerator operation. A calculating model was set up in this paper to study the belt vibration. The results show that the belt tension, belt velocity and belt current all contribute to the belt vibration. There is an optimal relationship among the three factors by which the belt would run most smoothly. There exists a minimum value of optimal tension for various belt velocities. The vibrating frequency of the is generally around several Hz.

  16. Natural radioactivity in soil and ground waters in uranium mineralised belt in east Singhbhum, Jharkhand, India

    International Nuclear Information System (INIS)

    The geologically well-known Singhbhum Thrust Belt of Jharkhand State in India is depository of a variety of minerals including a few low-grade uranium ore deposits. Mining and milling of uranium ores was commenced at Jaduguda three decades ago. Two other ore deposits at Bhatin and Narwapahar, located 3 and 12 km north-west of Jaduguda, were taken up for underground mining during mid 1980s and 1990s and ore deposits at Turamdih and Bagjata have been explored. Soil and ground water in different parts of this low-level uranium mineralisation area have been analysed to evaluate the natural radioactivity levels. This paper summarises the results of the study and their bearing on the natural radiation exposure in the area. (author)

  17. Australian Palaeozoic palaeomagnetism and tectonics—I. Tectonostratigraphic terrane constraints from the Tasman Fold Belt

    Science.gov (United States)

    Powell, C. McA.; Li, Z. X.; Thrupp, G. A.; Schmidt, P. W.

    The Tasman Fold Belt (TFB) of Eastern Australia can be divided into three meridional orogenic realms: the Kanmantoo, Lachlan-Thomson and New England Orogens. The geological histories of the orogens overlap, but each is distinctive. The Kanmantoo Orogen was provenance-linked to the Australian craton in the Early Cambrian, and accreted to Australia by Late Cambrian. There are many possible tectonostratigraphic terranes in the Lachlan Fold Belt (LFB) but these can be simplified to two major amalgamated terranes by the Middle Silurian. All the LFB terranes appear provenance-linked in the Ordovician, and were progressively covered, from the west, during the Late Silurian to Late Devonian, by a quartzose overlap assemblage. The New England Orogen has a fragmentary Early Palaeozoic history, but from the Devonian onwards its geology is related to a series of volcanic island and continental margin magmatic arcs. There is some evidence of provenance-linking between the Lachlan and New England Orogens in the Devono-Carboniferous but docking is not demonstrated until the mid-Carboniferous. The few reliable pre-Late Carboniferous palaeomagnetic poles available from the TFB come from the eastern LFB. The poles post-date accretion of the LFB to the Australian craton. Thus, the possibility that parts of the Lachlan-Thomson and New England Orogens contain exotic elements is yet to be tested palaeomagnetically.

  18. Equilibria and Free Vibration of a Two-Pulley Belt-Driven System with Belt Bending Stiffness

    Directory of Open Access Journals (Sweden)

    Jieyu Ding

    2014-01-01

    Full Text Available Nonlinear equilibrium curvatures and free vibration characteristics of a two-pulley belt-driven system with belt bending stiffness and a one-way clutch are investigated. With nonlinear dynamical tension, the transverse vibrations of the translating belt spans and the rotation motions of the pulleys and the accessory shaft are coupled. Therefore, nonlinear piecewise discrete-continuous governing equations are established. Considering the bending stiffness of the translating belt spans, the belt spans are modeled as axially moving beams. The pattern of equilibria is a nontrivial solution. Furthermore, the nontrivial equilibriums of the dynamical system are numerically determined by using two different approaches. The governing equations of the vibration near the equilibrium solutions are derived by introducing a coordinate transform. The natural frequencies of the dynamical systems are studied by using the Galerkin method with various truncations and the differential and integral quadrature methods. Moreover, the convergence of the Galerkin truncation is investigated. Numerical results reveal that the study needs 16 terms after truncation in order to determine the free vibration characteristics of the pulley-belt system with the belt bending stiffness. Furthermore, the first five natural frequencies are very sensitive to the bending stiffness of the translating belt.

  19. The great West Road

    CERN Multimedia

    1975-01-01

    From right to centre the 'Nationale 84' relying Meyrin to Saint-Genis. The fence limits Lab I on that side. From bottom the road leading to the double inclined tunnel linking Lab I and Lab II. On the foreground the ISR building (left) and the West Hall (centre).

  20. West African Antislavery Movements

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi; Pelckmans, Lotte

    2011-01-01

    In the context of liberalization of West African political regimes, the upsurge of audacious political entrepreneurs who want to end chattel slavery in their nation-state, resulted in the legal criminalisation of slavery in both Mauritania (2007) and Niger (2003) and in a proposal to revise the...... cultures (or ‘mentalities’) go hand in hand....

  1. First Steps Towards the Paleoseismological History of the Pastores and Venta de Bravo Faults, Acambay Graben, Trans-Mexican Volcanic Belt, Central Mexico

    Science.gov (United States)

    Persaud, M.; Zúñiga, F. R.; Aguirre-Díaz, G.; Villamor, P.; Langridge, R.

    2006-12-01

    The Acambay graben is part of the Trans-Mexican Volcanic Belt (TMVB) which strikes ESE-WNW across central Mexico. The belt is an active, calc-alkaline volcanic arc that is related to the subduction of the Rivera and Cocos plates underneath the North American plate (e.g. Suter et al. 1995). The TMVB comprises a series of intra-arc basins that form the Chapala-Tula fault zone (450 km long, 50 km wide, Suter et al. 1995). The Acambay graben is c. 80 km long, 15 to 35 km wide and limited by four large E-W striking normal faults that are from west to east, the Epitacio-Huerta (EHF) and the Acambay-Tixmadejé faults (ATF) in the north and the Venta de Bravo (VBF) and the Pastores faults (PF) in the south. In the region, there is a low current seismicity but two known historic earthquakes occurred in the graben, the November 19, 1912, ms = 7.0 Acambay event and the February 22, 1979, ms = 4.9 Maravatío earthquake (Astíz-Delgado 1980). The paleoseismic history of the ATF has been previously studied by Langridge et al. (2000). Our focus lies on the paleoseismicity of the southern faults. The rupture history is assessed by tectonic geomorphology and paleoseismic trenches. To study the recent paleoseismic history of the two southern faults, we excavated two trenches on the PF. These trenches lie on young alluvial fans protruding from the Pastores fault scarp. Their location was chosen because of ' steps'\\ in the surface of the alluvial fan that might indicate the position of the most recent fault scarps, in combination with georadar profiles that confirmed vertical displacements in reflectors underneath those steps. The strata in the trenches consist of lake sediments at the base of one trench overlain by interbedded volcanic pyroclastic flows and ash falls which are found in both trenches. In both trenches we found evidence for one paleoearthquake respectively. We are in the process of dating these events by means abundant charcoal which we found in the pyroclastic

  2. Magnetotelluric characterization through the Ambargasta-Sumampa Range: The connection between the northern and southern trace of the Río de La Plata Craton - Pampean Terrane tectonic boundary

    Science.gov (United States)

    Peri, V. Gisel; Barcelona, Hernan; Pomposiello, M. Cristina; Favetto, Alicia

    2015-04-01

    The South American Platform was part of the Western Gondwana, a collage of plates of different ages assembled in late Neoproterozoic to Cambrian times. The Transbrasiliano Lineament, a continental shear belt that transversely intersects this platform from NE to SW, has its southern expression in the tectonic boundary between the Río de La Plata Craton and the Pampean Terrane. Magnetotelluric long-period data in a W-E profile (29°30‧ S) that crosses the Ambargasta-Sumampa Range and the Chaco-Pampean Plain were obtained to connect information of this mostly inferred tectonic boundary. A 2-D inversion model shows the Chacoparanense basin, Río Dulce lineament, Ambargasta-Sumampa Range and Salina de Ambargasta in the upper crust. At mid-to-lower crust and 40 km to the east of the Ambargasta-Sumampa Range, a discontinuity (500-2000 Ω m) of 20-km-wide separates two highly resistive blocks, the Río de La Plata Craton (6000-20,000 Ω m) in the east, and the Pampean Terrane (5000-20,000 Ω m) in the west. This discontinuity represents the tectonic boundary between both cratons and could be explained by the presence of graphite. The geometry of the Pampean Terrane suggests an east-dipping paleo-subduction. Our results are consistent with gravimetric and seismicity data of the study area. A more conductive feature beneath the range and the tectonic boundary was associated with the NE-SW dextral transpressive system evidenced by the mylonitic belts exposed in the Eastern Pampean Ranges. This belt represents a conjugate of the mega-shear Transbrasiliano Lineament and could be explained by fluid-rock interaction by shearing during hundreds of years. The eastern border of the Ambargasta-Sumampa Range extends the trace of the Transbrasiliano Lineament. The electrical Moho depth (40 km to the west and 35 km to the east) was identified by a high electrical contrast between the crust and upper mantle. The upper mantle shows a resistive structure beneath the Río de La Plata

  3. The Foundations of Radiation Belt Research

    Science.gov (United States)

    Ludwig, G. H.

    2008-12-01

    phenomenon. It also provided the first hint that there were two distinct radiation belts, although that conclusion was not reached until later. Although that new information was quickly announced, the results of the high altitude nuclear detonations were kept secret until well into 1959. They clearly revealed the charged particle shells created by the Argos nuclear detonations. The next major step in mapping and understanding the high-intensity radiation involved the launch of deep space probes Pioneers III and IV in December 1958 and March 1959. Although both launches fell short in their primary objective, to reach the moon, they traveled far enough from the Earth to fully meet the needs of the scientific experiment. They very clearly showed the two-radiation belt structure, and mapped its extent. They also showed the probable effect of a magnetic storm on 25 February, thus indicating the direct influence of solar activity on the outer belt. By the end of 1959, the existence of the Van Allen Radiation Belts and their general structure were solidly established, early information about the composition of the radiation was appearing in print, and energetic work was under way to understand the physics of the processes involved.

  4. Space electronics: radiation belts set new challenges

    International Nuclear Information System (INIS)

    Telecommunications satellites have been in use since 1962 with the first satellite network (constellation) coming into operation in 1966. GPS systems have been available since the mid seventies. Until now, all these systems have avoided orbits which lie within the radiation belts. The latest constellation projects, offering much wider bandwidths, need to use orbits between 1500 and 2000 km, where the proton density is at its highest. The vulnerability of future generations of components can be predicted by extrapolating the behaviour of current devices. Screening is not a viable option due to cost and weight limitations in satellite applications. As a result, satellite and component manufacturers are seeking new methods of hardening components or making them more radiation tolerant in an environment where the radiation levels are ten times those currently experiences. (authors)

  5. The east-west asymmetry in Coronal Mass Ejections: evidence for active longitudes

    OpenAIRE

    Skirgiello, M.

    2005-01-01

    Various manifestations of solar activity are not uniformly distributed with heliographic longitude. By using east-west asymmetry in the occurrence rate of CMEs (coronal mass ejections), the longitudinal dependence in SOHO LASCO 1996-2004 data has been studied in this work. The solar rotation periodicity has been found, indicating the presence of active longitudes, whose phase is reversed twice during the studied period. It is more prominent in the Southern Hemisphere. The east-west a...

  6. Is the Paleoproterozoic Jiao-Liao-Ji Belt (North China Craton) a rift?

    Science.gov (United States)

    Li, Zhuang; Chen, Bin; Wei, Chunjing

    2016-04-01

    As a typical example of the Paleoproterozoic crust in the Eastern Block of the North China Craton, the Paleoproterozoic Jiao-Liao-Ji Belt consists principally of the Liaohe Group (and its equivalents), Liaoji granites and mafic intrusions. Previous studies indicate that the evolution of the Jiao-Liao-Ji Belt has been mainly attributed to the opening and closing of an intracontinental rift along the eastern continental margin of the North China Craton. Here we synthesize the Paleoproterozoic magmatism, sedimentation, metamorphism and metallogeny against the rift model and propose a process of arc-continent collision between the northern Longgang and the southern Nangrim Blocks. This conclusion is consistent with the observations, including that (a) the 2.0- to 2.2-Ga magmatism shows a typical subalkaline series, rather than a bimodal distribution, since the mafic rocks mostly have arc affinities and the acidic-intermediate rocks belong to the calc-alkaline series; (b) the main source of the 1.9- to 2.0-Ga sedimentary rocks is the Paleoproterozoic arc materials, indicating a fore-arc or back-arc basin setting; (c) a couple of big borate deposits occur in the boron-rich volcanic rocks that were formed in convergent continental margins; (d) the North and South Liaohe Groups show different rock associations and metamorphic histories (P-T paths); and (e) the Nangrim and Longgang Blocks vary in lithological units, geochronology and metamorphic features. Thus, an arc-continent collision tectonic scenario for the Paleoproterozoic Jiao-Liao-Ji Belt is involved: (a) a southward subduction in the period 2.0-2.2 Ga; (b) sedimentation during the period 1.9-2.0 Ga; (c) arc-continent collision at ca. 1.9 Ga; and (d) post-collisional extension at 1.82-1.87 Ga, marking the end of the Paleoproterozoic tectonothermal event.

  7. Evaluation of Recent Tectonomagmatic Discrimination Diagrams and their Application to the Origin of Basic Magmas in Southern Mexico and Central America

    Science.gov (United States)

    Verma, Surendra P.; Verma, Sanjeet K.; Pandarinath, Kailasa; Rivera-Gómez, María Abdelaly

    2011-08-01

    Discrimination diagrams to decipher tectonic settings have been in use for nearly 40 years. Although old diagrams have been extensively used, the recent ones based on discriminant functions of ratio variables, with or without log-transformation, proposed during 2004-2010 for the discrimination of four tectonic settings of island arc, continental rift, ocean-island and mid-ocean ridge, were newly evaluated to show their high success rates of 57.3-100% and 58.5-100% for major-element and immobile-element based diagrams, respectively. For the continental arc of the Andes evaluated for its similarity to island arc, these four sets of diagrams showed success rates of 62.1-83.8%. These four sets of five diagrams per set were therefore used to infer tectonic setting of the Mexican Volcanic Belt (MVB), Los Tuxtlas volcanic field (LTVF), and Central American Volcanic Arc (CAVA). Using this approach, the MVB, especially its western, central and eastern parts, and the LTVF of Southern Mexico show a dominantly continental rift setting and the CAVA shows an arc setting. The west-central part of the MVB is consistent with dual tectonics of arc and rift. These results confirm the application of an unusual mantle upwelling rift-model for the Mexican on-land volcanism, whereas the conventional plate tectonic subduction model seems to be applicable for the CAVA from Guatemala to north-western Costa Rica.

  8. U-Pb zircon constraints on the age of the Cretaceous Mata Amarilla Formation, Southern Patagonia, Argentina: Its relationship with the evolution of the Austral Basin

    International Nuclear Information System (INIS)

    Despite the abundant fossil content of the Mata Amarilla Formation (Southern Patagonia, Santa Cruz Province, Argentina), its age has always generated a considerable number of questions and debates. The chronological data provided by invertebrates, dinosaurs, fish, turtles, plesiosaurs and fossil flora are contradictory. In this work, twenty U-Pb spot analyses by laser ablation were carried out on the outer parts of the zoned zircon crystals from a tuff layer of the middle section of the Mata Amarilla Formation, yielding a U-Pb concordia age of 96.23±0.71 Ma, which corresponds to the middle Cenomanian. The deposition of the lower section of the Mata Amarilla Formation marks the onset of the foreland stage of the Austral Basin (also known as Magallanes Basin); this transition is characterized by the west-east shift of the depositional systems, which is consistent with the progradation of the Cretaceous fold-and-thrust belt. Thus, the onset of the foreland stage could have occurred between the upper Albian and lower Cenomanian, as the underlying Piedra Clavada Formation is lower Albian in age. On comparing the data obtained with information from the Ultima Esperanza Province in Chile, it can be suggested that the initiation of the closure of the Rocas Verdes Marginal Basin occurred simultaneously

  9. FAQ: General Questions about West Nile Virus

    Science.gov (United States)

    ... Public Service Videos General Questions About West Nile Virus Recommend on Facebook Tweet Share Compartir On this ... West Nile virus cases? What is West Nile virus? West Nile virus is an arthropod-borne virus ( ...

  10. Tectonomagmatic relationship between the Sierra Madre Occidental ignimbrite flare-up and the southern Basin and Range province

    Science.gov (United States)

    Aguirre-Diaz, G. J.; Labarthe-Hernandez, G.

    2004-12-01

    The Sierra Madre Occidental (SMO) is a Mid-Tertiary, large-volume, ignimbrite province at least 1,200 km long and 200-500 km wide, extending continuously from the U.S.-Mexico border (31\\deg N) to its intersection with the Mexican Volcanic Belt (21\\deg N). Considering the average thickness of 1,000 m for the ignimbrite plateau, based on several measured sections along the province, and the average wide of the province of 300 km, a conservative estimate of the physical volume of the SMO ignimbrites is about 360,000 km3. The southern part of the Basin and Range province is in Mexico. This extensional province overlaps in space and time with the SMO ignimbrite flare-up and formed NW- to NE-trending normal faults that bound many large grabens, which are particularly long and deep in the southern SMO. Basin and Range faulting occurred between at least 32 Ma and 12 Ma with both limits probably extending until the Eocene and the Quaternary. Ignimbrite activity can be as old as 51 Ma and as young as 17-16 Ma, but most of the ignimbrite volume was erupted in the 38-23 Ma period. Thus, the ignimbrite flare-up can be defined as a period of intense explosive volcanic activity that produced enormous volumes of silicic ignimbrite sheets, which took place mainly between 38 and 23 Ma in Mexico. The ignimbrite flare-up coincided in time with peaks in Basin and Range faulting, and the ignimbrite activity apparently migrated from the east-northeast to the west-southwest, i.e., from central Chihuahua (38-27 Ma) to Durango-Tayoltita-Nazas (32-29 Ma) to Zacatecas-Tepic (24-23 Ma), finishing by 16 Ma at Jalisco-Nayarit, as deduced from the compilation of geologic works done in the SMO. It is unknown yet whether there was a west-southward migration of Basin and Range faulting and if the ignimbrite flare-up occurred episodically as peaks (38-27 Ma, 32-29 Ma, and 24-23 Ma) or was continuous. Nevertheless, by the time that the ignimbrite flare-up started, the Basin and Range extension was

  11. Ecological speciation in Nolina parviflora (Asparagaceae: lacking spatial connectivity along of the Trans-Mexican Volcanic Belt.

    Directory of Open Access Journals (Sweden)

    Eduardo Ruiz-Sanchez

    Full Text Available The hypothesis of ecological speciation states that as populations diverge in different niches, reproductive isolation evolves as a by-product of adaptation to these different environments. In this context, we used Nolina parviflora as a model to test if this species evolved via ecological speciation and to explore current and historical gene flow among its populations. Nolina parviflora is a montane species endemic to Mexico with its geographical distribution restricted largely to the Trans-Mexican Volcanic Belt. This mountain range is one of the most complex geological regions in Mexico, having undergone volcanism from the mid-Miocene to the present. Ecologically, the Trans-Mexican Volcanic Belt possesses different types of vegetation, including tropical dry forest; oak, pine, pine-oak, and pine-juniper forests; and xerophytic scrub--all of which maintain populations of N. parviflora. Using species distribution models, climatic analyses, spatial connectivity and morphological comparisons, we found significant differences in climatic and morphological variables between populations of N. parviflora in two distinct Trans-Mexican Volcanic Belt regions (east vs. west. This could mean that the geographically isolated populations diverged from one another via niche divergence, indicating ecological speciation. Spatial connectivity analysis revealed no connectivity between these regions under the present or last glacial maximum climate models, indicating a lack of gene flow between the populations of the two regions. The results imply that these populations may encompass more than a single species.

  12. The Herpetology of the Southern Kalahari domain

    Directory of Open Access Journals (Sweden)

    W. D Haacke

    1984-12-01

    Full Text Available The herpetofauna of the southern Kalahari has mixed affinities, as this area lies on a rainfall gradient in a critical area where a transition between the arid south-west and the moister north-east takes place. As the variation in substrate type is relatively limited, the effect of the rainfall gradient appears to influence and determine the range limits of many taxa in both directions, resulting in an area in which of 55 recorded reptiles, 11 western taxa overlap or form a parapatric zone with 25 eastern taxa, while the remaining taxa are endemic or wideranging.

  13. The Herpetology of the Southern Kalahari domain

    OpenAIRE

    W. D Haacke

    1984-01-01

    The herpetofauna of the southern Kalahari has mixed affinities, as this area lies on a rainfall gradient in a critical area where a transition between the arid south-west and the moister north-east takes place. As the variation in substrate type is relatively limited, the effect of the rainfall gradient appears to influence and determine the range limits of many taxa in both directions, resulting in an area in which of 55 recorded reptiles, 11 western taxa overlap or form a parapatric zone wi...

  14. Chemical weathering in active mountain belts controlled by stochastic bedrock landsliding

    Science.gov (United States)

    Emberson, Robert; Hovius, Niels; Galy, Albert; Marc, Odin

    2016-01-01

    A link between chemical weathering and physical erosion exists at the catchment scale over a wide range of erosion rates. However, in mountain environments, where erosion rates are highest, weathering may be kinetically limited and therefore decoupled from erosion. In active mountain belts, erosion is driven by bedrock landsliding at rates that depend strongly on the occurrence of extreme rainfall or seismicity. Although landslides affect only a small proportion of the landscape, bedrock landsliding can promote the collection and slow percolation of surface runoff in highly fragmented rock debris and create favourable conditions for weathering. Here we show from analysis of surface water chemistry in the Southern Alps of New Zealand that weathering in bedrock landslides controls the variability in solute load of these mountain rivers. We find that systematic patterns in surface water chemistry are strongly associated with landslide occurrence at scales from a single hillslope to an entire mountain belt, and that landslides boost weathering rates and river solute loads over decades. We conclude that landslides couple erosion and weathering in fast-eroding uplands and, thus, mountain weathering is a stochastic process that is sensitive to climatic and tectonic controls on mass wasting processes.

  15. The Gould's Belt Distances Survey (GOBELINS) III. Distances and structure towards the Orion Molecular Clouds

    CERN Document Server

    Kounkel, Marina; Loinard, Laurent; Ortiz-León, Gisela N; Mioduszewski, Amy J; Rodríguez, Luis F; Dzib, Sergio A; Torres, Rosa M; Pech, Gerardo; Galli, Phillip A B; Rivera, Juana L; Boden, Andrew F; Evans, Neal J; Briceño, Cesar; Tobin, John J

    2016-01-01

    We present the results of the Gould's Belt Distances Survey (GOBELINS) of young star forming regions towards the Orion Molecular Cloud Complex. We detected 36 YSOs with the Very Large Baseline Array (VLBA), 27 of which have been observed in at least 3 epochs over the course of 2 years. At least half of these YSOs belong to multiple systems. We obtained parallax and proper motions towards these stars to study the structure and kinematics of the Complex. We measured a distance of 388$\\pm$5 pc towards the Orion Nebula Cluster, 428$\\pm$10 pc towards the southern portion L1641, 388$\\pm$10 pc towards NGC 2068, and roughly $\\sim$420 pc towards NGC 2024. Finally, we observed a strong degree of plasma radio scattering towards $\\lambda$ Ori.

  16. Tectonic Map of the Ellesmerian and Eurekan deformation belts on Svalbard, North Greenland and the Queen Elizabeth Islands (Canadian Arctic)

    Science.gov (United States)

    Piepjohn, Karsten; von Gosen, Werner; Tessensohn, Franz; Reinhardt, Lutz; McClelland, William C.; Dallmann, Winfried; Gaedicke, Christoph; Harrison, Christopher

    2016-04-01

    The tectonic map presented here shows the distribution of the major post-Ellesmerian and pre-Eurekan sedimentary basins, parts of the Caledonian Orogen, the Ellesmerian Fold-and-Thrust Belt, structures of the Cenozoic Eurekan deformation, and areas affected by the Eurekan overprint. The present continental margin of North America towards the Arctic Ocean between the Queen Elizabeth Islands and Northeast Greenland and the present west margin of the Barents Shelf are characterized by the Paleozoic Ellesmerian Fold-and-Thrust Belt, the Cenozoic Eurekan deformation, and, in parts, the Caledonian Orogen. In many areas, the structural trends of the Ellesmerian and Eurekan deformations are more or less parallel, and often, structures of the Ellesmerian Orogeny are affected or reactivated by the Eurekan deformation. While the Ellesmerian Fold-and-Thrust Belt is dominated by orthogonal compression and the formation of wide fold-and-thrust zones on Ellesmere Island, North Greenland and Spitsbergen, the Eurekan deformation is characterized by a complex network of regional fold-and-thrust belts (Spitsbergen, central Ellesmere Island), large distinct thrust zones (Ellesmere Island, North Greenland) and a great number of strike-slip faults (Spitsbergen, Ellesmere Island). The Ellesmerian Fold-and-Thrust Belt was most probably related to the approach and docking of the Pearya Terrane (northernmost part of Ellesmere Island) and Spitsbergen against the north margin of Laurasia (Ellesmere Island/North Greenland) in the earliest Carboniferous. The Eurekan deformation was related to plate tectonic movements during the final break-up of Laurasia and the opening of Labrador Sea/Baffin Bay west, the Eurasian Basin north, and the Norwegian/Greenland seas east of Greenland. The tectonic map presented here shows the German contribution to the Tectonic Map of the Arctic 1:5,000,000 (TeMAr) as part of the international project "Atlas of geological maps of Circumpolar Arctic at 1

  17. Warming and extensive glacier recession at Southern Hemisphere middle latitudes during Heinrich Stadial 1

    Science.gov (United States)

    Putnam, A. E.; Schaefer, J. M.; Denton, G. H.; Hall, B. L.; Lowell, T. V.; Porter, C. T.; Barrell, D. J.; Andersen, B. G.; Kaplan, M. R.; Koffman, T.; Lennon, J.; Rowan, A. V.; Finkel, R. C.; Rood, D.; Schwartz, R.; Vandergoes, M.; Plummer, M. A.; Brocklehurst, S. H.; Kelley, S. E.; Ladig, K. L.

    2013-12-01

    The termination of the last ice age featured a major reconfiguration of Earth's climate and cryosphere, yet the underlying causes of these massive changes continue to be debated. Documenting the spatial and temporal variations of atmospheric temperature during deglaciation can help discriminate among potential drivers. Here, we present 10Be surface-exposure chronologies and glaciological reconstructions of ice recession following the Last Glacial Maximum in the New Zealand Southern Alps and Patagonian Andes. Our field sites straddle opposite sides of the South Pacific and record climate changes near Southern Ocean fronts. Most of the deglacial warming in the Southern Alps and southern Andes occurred during the early part of the Heinrich Stadial 1 (HS1) of the North Atlantic region. We attribute southern mid-latitude warming and glacier recession during HS1 to a southward shift of the Subtropical and Subantarctic Fronts. Because these oceanic fronts are associated with the position of the westerly wind belt, our findings support the concept that a southward shift of Earth's wind belts accompanied the early parts of HS1 cooling in the North Atlantic, leading to major warming and deglaciation in southern middle latitudes.

  18. The optimization of steelcord belt splices; Optimierung von Stahlseilgurtverbindungen

    Energy Technology Data Exchange (ETDEWEB)

    Hager, M. [Hannover Univ. (Germany); Keller, M. [ContiTech Transportbandsysteme GmbH, Northeim (Germany)

    2002-03-01

    Belt-conveyors have proven themselves for the continuous bulk conveying under technical and economic points of view for a long time. For long belt conveyors and big mass flows, steelcord conveyor belts technologically represent the state of the art. In a steelcord belt splice, the tensile force between the spliced belt ends is transmitted almost completely by locally differing shear forces in the rubber of the elastomer composite construction. Under the dynamically swelling load, to which the belt is exposed in operation, the splices represent the weakest part of a conveyor belt. In experimental examinations of this paper it was found, that the characteristic behavior of the material of the elastomer and the constructive design influences distortion behavior under force of steelcord belt test samples. As most important parameter of the compound design, the filler proves itself as the strongest influence on the dynamic shear modulus, which characterizes the non linear dynamic stiffness of the elastomer. The filling degree and the filler composition influence the degree of non linearity of the dynamic shear modulus and its complex components. On the basis of the results of the experimental examinations, an approximation model of the non linear dynamic shear modulus was employed, with which it is possible, to characterize the non linear, amplitude dependent material behavior of the examined elastomer. In the scope of this paper, a program system was developed on basis of the finite element method, that allows the arithmetical simulation of the force flow in steelcord belt splices and in highly stressed areas of the splices. (orig.)

  19. Detection of Small Kuiper Belt Objects by Stellar Occultations

    OpenAIRE

    Stevenson, R

    2007-01-01

    Knowledge of the Kuiper Belt is currently limited to those objects that can be detected directly. Objects with diameters less than $\\sim$10km reflect too little light to be detected. These smaller bodies could contain most of the mass in the Kuiper Belt while the abundance of these bodies may constrain the distribution of mass. The overall size distribution of bodies within the Kuiper Belt can also be inferred from the relative abundances of sub-km and larger bodies. Stellar occultations are ...

  20. Into the Kuiper Belt: New Horizons Post-Pluto

    Science.gov (United States)

    Harrison Parker, Alex; Spencer, John; Benecchi, Susan; Binzel, Richard; Borncamp, David; Buie, Marc; Fuentes, Cesar; Gwyn, Stephen; Kavelaars, JJ; Noll, Keith; Petit, Jean-Marc; Porter, Simon; Showalter, Mark; Stern, S. Alan; Sterner, Ray; Tholen, David; Verbiscer, Anne; Weaver, Hal; Zangari, Amanda

    2015-11-01

    New Horizons is now beyond Pluto and flying deeper into the Kuiper Belt. In the summer of 2014, a Hubble Space Telescope Large Program identified two candidate Cold Classical Kuiper Belt Objects (KBOs) that were within reach of New Horizons' remaining fuel budget. Here we present the selection of the Kuiper Belt flyby target for New Horizons' post-Pluto mission, our state of knowledge regarding this target and the potential 2019 flyby, the status of New Horizons' targeting maneuver, and prospects for near-future long-range observations of other KBOs.

  1. Ebola in West Africa

    OpenAIRE

    Lul Raka; Monica Guardo

    2015-01-01

    Ebola viral disease (EVD) is a severe and life-threatening disease. The current Ebola outbreak in West Africa entered its second year and is unprecedented because it is the largest one in history, involved urban centers and affected a large number of health care workers. It quickly escalated from medical into a humanitarian, social, economic, and security crisis. The primary pillars to prevent EVD are: early diagnosis, isolation of patients, contact tracing and monitoring, safe burials, infec...

  2. Petrology of the Plutonic Rocks of west-central Alaska

    Science.gov (United States)

    Miller, Thomas P.

    1970-01-01

    A series of plutons in west-central Alaska defines the Hogatza plutonic belt which extends for about 200 miles in an east-west direction from the northeastern Seward Peninsula to the Koyukuk River. The plutonic rocks have an aggregate area of about 1,200 square miles and their composition, distribution, and possible petrogenesis are discussed for the first time in this report. Field, petrographic and chemical data supported by K/Ar age dating indicate the plutonic rocks are divisible into two suites differing in age, location, and composition. The western plutons are mid-Cretaceous (~100 m.y.) in age and consist of a heterogeneous assemblage of monzonite, syenite, quartz monzonite. Associated with these granitic rocks is a group of alkaline sub-silicic rocks that forma belt of intrusive complexes extending for a distance of at least 180 miles from west-central Alaska to the Bering Sea. The complex at Granite Mountain shows a rare example of zoning from an alkaline rim to a quartz-bearing core. The occurrence of a similar complex at Cape Dezhnev on the easternmost tip of Siberia suggests the alkaline province may extend into Siberia. The easternmost plutons are Late Cretaceous (180 m.y.) in age and composed primarily of granodiorite and quartz monzonite similar to calc-alkaline plutons found throughout the North America Cordillera. The plutons are epizonal and intrude deformed but unmetamorphosed Lower Cretaceous andesitic volcanics and volcanic graywacke which constitute the highly mobile Yukon-Koyukuk volcanogenic province of west-central Alaska. No older rocks have been found within the confines of this vast tract; the occurrence of a bounding ophiolite sequence has lead to the suggestion that the province was formed by large-scale rifting and is underlain by oceanic crust. The possibility of no juvenile sialic crust over much of the area suggests that the potassium-rich magma now represented by the alkaline rocks originated in the mantle. The distribution of the

  3. Drought in West Africa

    Science.gov (United States)

    2007-01-01

    Drought settled over West Africa's Ivory Coast region when wet season rains came late in 2007. Instead of beginning in February, the rainy season didn't start until March, and steady rains didn't start until late March, said the Famine Early Warning System Network. Though the rain had started to alleviate the drought, vegetation was still depressed in parts of Cote d'Ivoire (Ivory Coast) between March 22 and April 6, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured the data used to make this image. The image shows current vegetation conditions compared to average conditions recorded since 2000. Areas where plants are growing more slowly or more sparsely than average are brown, while areas where vegetation is denser than average are green. The brown tint that dominates the image indicates that plants through most of the country are more sparse than normal. Among the crops affected by the lack of rain was West Africa's cocoa crop. About 70 percent of the world's cocoa comes from West Africa, and Cote d'Ivoire is a top grower, said Reuters. Cocoa prices climbed as the crop fell short. Farmers called the drought the worst in living memory, Reuters said. The delay in rainfall also led to water shortages in parts of Cote d'Ivoire, according to the United Nations Office for the Coordination of Humanitarian Affairs.

  4. Syn- and post-tectonic granite plutonism in the Sausar Fold Belt, central India: Age constraints and tectonic implications

    Science.gov (United States)

    Chattopadhyay, Anupam; Das, Kaushik; Hayasaka, Yasutaka; Sarkar, Arindam

    2015-08-01

    Sausar Fold Belt (SFB) in central India forms the southern part of the Central Indian Tectonic Zone (CITZ) - a crustal scale Proterozoic mobile belt dissecting the Indian craton, whose tectonothermal history and age is important for understanding the Proterozoic crustal history of the Indian craton. SFB comprises a gneissic basement (TBG: Tirodi Biotite Gneiss) overlain by a supracrustal sequence of quartzite-pelite-carbonate (SSG: Sausar Group). SSG and TBG are deformed and metamorphosed in greenschist to amphibolite facies. Two phases of granite intrusion are observed in the SSG - a syntectonic foliated granite and a post-tectonic massive granite, with clear structural relationship with the host rocks. Monazite chemical dating (U-Th-total Pb) of the foliated and massive granites yield Neoproterozoic (ca. 945-928 Ma) ages that contradict many earlier geochronological interpretations. Foliated granites and the immediately adjacent TBG show monazite grains with ca. 945 Ma mean age, interpreted as the timing of D2 deformation and amphibolite facies metamorphism of SSG. The post tectonic granites intruded these rocks around 928 Ma, and were largely undeformed. A terminal thermal overprint is found in some monazite grain rims at ca. 785 Ma age. The younger Sausar tectonothermal events have overprinted the adjacent high-grade granulites of Ramakona-Katangi Granulite (RKG) belt, and should not be considered as parts of the same tectonothermal event representing different depth sections only.

  5. MACRO MODEL OF SEAT BELT USE BY CAR DRIVERS AND PASSENGERS

    Directory of Open Access Journals (Sweden)

    Kazimierz JAMROZ

    2013-12-01

    Full Text Available The article presents some problems of seat belt use by car drivers and passengers. It looks in particular at seat belt use and effectiveness in selected countries. Next, factors of seat belt use are presented and methodology of model development. A macro model of seat belt use is presented based on data from around fifty countries from different continents.

  6. Geochronologic studies in the Grants mineral belt

    International Nuclear Information System (INIS)

    Geologic observation coupled with radiometric age dating can be used to assess ages of ore formation and, in some cases, ages of sedimentation in the Grants mineral belt. Rb-Sr studies indicate the earliest mineralization is trend ore at Ambrosia Lake and Smith Lake, dated at 139 +- 9.5 m.y. This date is similar to that for barren-rock montmorillonite from the Jackpile sandstone (Late Jurassic): 142 +- 14 m.y.; it may be used, with caution, to indicate the minimum age of sedimentation for the Morrison Formation. Geologic evidence indicates epigenetic rather than syngenetic ore formation. Barren-rock montmorillonites from Ambrosia Lake yield a poorly defined isochron of 132 +- 26 m.y. Early formed ore at the Jackpile-Paguate mine, Laguna district, was remobilized and reprecipitated at 113 +- 7 m.y. This date is older than the range of dates for the Dakota Formation (Cretaceous) and Mancos Shale. The 113 +- 7 m.y. mid-Cretaceous date for the Jackpile-Paguate ore is consistent with geologic evidence; geologic control suggests that other ore deposits are post-Late Jurassic but pre-Dakota Formation. Based on geologic evidence, mineralization in the Dakota Formation is thought to be very young. Laramide mineralization (60 to 70 m.y.) is evidenced by the presence of some stack ore. At least one uranium deposit, located partly in oxidized ground at the main redox front of the Grants mineral belt, may represent Tertiary mineralization; the clay-mineral Rb-Sr systematics of this deposit have been severely perturbed. Younger mineralization is indicated by U-Pb dates on uranophane (9 to 10 m.y.), and Pleistocene mineralization is noted for some ore. U-Pb dates of U4+ -rich ore minerals cluster between 80 and 100 m.y., although some are as old as 140 to 150 m.y. K-Ar dates on clay minerals range from 49 to 138 m.y. The reasons for this scatter are not known, although loss of radiogenic 40Ar due to burial is probable

  7. Archaean greenstone belt tectonism and basin development: some insights from the Barberton and Pietersburg greenstone belts, Kaapvaal Craton, South Africa

    Science.gov (United States)

    de Wit, Maarten J.

    The sediments in two of South Africa's major Archaean greenstone belts, the Barberton and Pietersburg greenstone belts, span an age range of some 800 million years. Both greenstone belts represent remnants of extensive fold and thrust belts with complex, but different polyphase tectonic histories. The oldest sediments were deposited between circa 3470 and 3490 M.a. on oceanic like crust preserved in the Barberton belt, possibly at the same time as sedimentation on similar oceanic crust preserved in the Pietersburg belt. Thereafter, the geologic evolution of these two belts diverged considerably. In the Barberton belt, there is clear evidence that the oceanic crust and sediments were obducted onto an intra-arc basin environment within 50 million years of its formation. The sequence was later further imbricated by northwest directed thrust stacking between 3300-3200 M.a. Basin development during both periods of thrusting took place in close proximity to active "calc-alkaline" arc systems. Deformation of the sediments within these basins took place while the same sediments were being deposited. Sedimentation took place predominantly in subaqueous environments, ranging from submarine mid-fans below the photic zone to tidal flats and deltaic plains. The sediments represent a polyhistory successor-type basin: early basins developed along a complex subduction related plate boundary; these basins later evolved into foreland depositories along and within collisional environments of an accretionary orogen. Late in the history of the Barberton greenstone belt (circa 3100 M.a.), the rocks were in places thermally reactivated and probably subjected to extensional processes; these processes overlapped in time with the main episodes of economic gold mineralization, and are of "early Witwatersrand-basin" age. The oceanic-like crust (including associated sediments) preserved in the Pietersburg belt was not significantly deformed until at least 500 million years after its formation

  8. Face-Saving Devices: Seat Belts and Air Bags

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160032.html Face-Saving Devices: Seat Belts and Air Bags Using ... 11 percent) suffered facial fractures -- nasal and mid-face fractures most often. Those most likely to suffer ...

  9. CRED REA Fish Team Belt Transect Survey at Laysan 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 3 sites at Laysan in the...

  10. Back belts in occupational setting: what are the evidences?

    Directory of Open Access Journals (Sweden)

    João Marcos Bernardes

    2012-01-01

    Full Text Available Although, widely used the mechanisms of action and the effectiveness of back belts in the prevention of occupational low back disorders remains uncertain, generating controversy about its use. Therefore, the purpose of this study was to do a critical literature review about back belts use in the prevention of occupational low back pain in the occupational setting. In order to do that, a bibliographic research in the following data basis: Medline, SciELO and LILACS was conducted. There is evidence that back belts use reduces spine range of motion, however the studies about intra-abdominal pressure and muscle activity presented contradictory results, as the epidemiologic studies, not allowing the recommendation of its use in the prevention of occupational low back pain. Based on this literature review it is suggested therefore, the implementation of new studies, to confirm or not the effectiveness of back belts as personal protective equipment, in the prevention of occupational low back disorders.

  11. A Physical Model of Electron Radiation Belts of Saturn

    Science.gov (United States)

    Lorenzato, L.; Sicard-Piet, A.; Bourdarie, S.

    2012-09-01

    Enrolling on the Cassini age, a physical Salammbô model for the radiation belts of Saturn have been developed including several physical processes governing the kronian magnetosphere. Results have been compared with Cassini MIMI LEMMS data.

  12. Tectonothermal evolution in the core of an arcuate fold and thrust belt: the south-eastern sector of the Cantabrian Zone (Variscan belt, north-western Spain)

    Science.gov (United States)

    Valín, María Luz; García-López, Susana; Brime, Covadonga; Bastida, Fernando; Aller, Jesús

    2016-07-01

    The tectonothermal evolution of an area located in the core of the Ibero-Armorican Arc (Variscan belt) has been determined by using the conodont colour alteration index (CAI), Kübler index of illite (KI), the Árkai index of chlorite (AI) and the analysis of clay minerals and rock cleavage. The area is part of the Cantabrian Zone (CZ), which represents the foreland fold and thrust belt of the orogen. It has been thrust by several large units of the CZ, what resulted in the generation of a large number of synorogenic Carboniferous sediments. CAI, KI and AI values show an irregular distribution of metamorphic grade, independent of stratigraphic position. Two tectonothermal events have been distinguished in the area. The first one, poorly defined, is mainly located in the northern part. It gave rise to very-low-grade metamorphism in some areas and it was associated with a deformation event that resulted in the emplacement of the last large thrust unit and development of upright folds and associated cleavage (S1). The second tectonothermal event gave rise to low-grade metamorphism and cleavage (S2) crosscutting earlier upright folds in the central, western and southern parts of the study area. The event continued with the intrusion of small igneous rock bodies, which gave rise to contact metamorphism and hydrothermal alteration. This event was linked to an extensional episode due to a gravitational instability at the end of the Variscan deformation. This tectonothermal evolution occurred during the Gzhelian-Sakmarian. Subsequently, several hydrothermal episodes took place and local crenulation cleavage developed during the Alpine deformation.

  13. A study on the geochemical characteristics of Upper Permian continental marginal arc volcanic rocks in the northern segment of South Lancangjiang Belt

    Institute of Scientific and Technical Information of China (English)

    SHEN Shangyue; FENG Qinglai; WEI Qirong; ZHANG Zhibin; ZHANG Hu

    2006-01-01

    Geochemical characteristics of the Upper Permian ( P2 ) continental marginal arc volcanic rocks are described, which have been found recently around the areas of Xiaodingxi and Zangli on the eastern side of the Yunxian-Lincang granite, in terms of rock assemblage, petrochemistry, REE, trace elements, Pb isotopes, geotectonic environment and so on. The volcanic rock assemblage is dominated by basalt-andesite-dacite, with minor trachyte andecite-trachyte; the volcanic rock series is predominated by the calc-alkaline series, with minor tholleiite series and alkaline series rocks; the volcanic rocks are characterized by high Al2O3 and low TiO2 , with K2O contents showing extremely strong polarity; the REE distribution patterns are characterized by LREE enrichment and right-inclined type; trace elements and large cation elements are highly enriched, Ti and Cr are depleted, and P and Nb are partially depleted; the Pb composition is of the Gondwana type; the petrochemical points mostly fall within the field of island-arc volcanic rocks, in consistency with the projection of data points of continental marginal volcanic rocks in the southern segment of the South Lancangjiang Belt and the North Lancangjiang Belt. This continental marginal arc volcanic rock belt, together with the ocean-ridge and ocean-island volcanic rocks and ophiolites in the Changning-Menglian Belt, constitute the ocean-ridge volcanic rock, ophiolite-arc rock-magmatic rock belts which are distributed in pairs, indicating that the Lancangjiang oceanic crust subducted eastwards. This result is of great importance in constraining the evolution of the paleo-Tethys in the Lancangjiang Belt.

  14. SPECIFIC RESISTANCE AND SPECIFIC INTENSITY OF BELT SANDING OF WOOD

    Directory of Open Access Journals (Sweden)

    Boleslaw Porankiewicz

    2010-06-01

    Full Text Available This paper examines and discusses the specific belt sanding resistance K (N·cm-2 and specific belt sanding intensity SI (g·cm-2·min-1, for wood of Pinus sylvestris L., Picea abies L., Quercus robra L., Acer pseudoplatanus L., Alnus glutinosa Gaertn., and Populus Nigra L., by different sanding pressure pS, different sanding grit NG number, and different wood grain angles Phi(v.

  15. Promoting automobile safety belt use by young children.

    OpenAIRE

    Sowers-Hoag, K M; Thyer, B A; Bailey, J S

    1987-01-01

    A program using behavioral practice, assertiveness training, and social and contrived reinforcers was developed to establish and maintain automobile safety belt use by young children. Sixteen children (ages 4.8 to 7 years) who never used their safety belts during a 5-day preexperimental observation period were randomly assigned to two groups of eight each. A multiple baseline design across groups was used to evaluate the effectiveness of the training program. During the 8-day baseline period ...

  16. Back belts in occupational setting: what are the evidences?

    OpenAIRE

    João Marcos Bernardes; Antonio Renato Pereira Moro

    2012-01-01

    Although, widely used the mechanisms of action and the effectiveness of back belts in the prevention of occupational low back disorders remains uncertain, generating controversy about its use. Therefore, the purpose of this study was to do a critical literature review about back belts use in the prevention of occupational low back pain in the occupational setting. In order to do that, a bibliographic research in the following data basis: Medline, SciELO and LILACS was conducted. There is evid...

  17. Tribological Properties of Metal V-Belt Type CVT Lubricant

    OpenAIRE

    Keiichi Narita

    2012-01-01

    The priority for lubricant performance for metal V-belt-type CVT (B-CVTFs) should be the improvement of transmittable torque capacity between the belt and pulley plus excellent antishudder properties for lockup clutch used in B-CVTs. This study intends to investigate the effect of lubricant additives for improving these performances of B-CVTs. In addition, surface analysis techniques were utilized to gain a novel insight into the chemical composites and morphology of the tribofilms. As a resu...

  18. Design of MGA trajectories for main belt asteroid

    Institute of Scientific and Technical Information of China (English)

    崔祜涛; 乔栋; 崔平远; 栾恩杰

    2003-01-01

    Asteroid exploration is one of the most sophisticated missions currently being investigated. Gravityassist trajectories have proven valuable in interplanetary missions such as the Pioneer, Voyager and Galileo. In this paper, we design interplanetary trajectory for main belt asteroid exploration mission with the Mars gravityassist (MGA) using "pork chop" plots and patched-conic theory and give some initial valuable trajectory parameters on main belt asteroid exploration mission with MGA.

  19. Occultation Searches for Kuiper Belt Objects

    CERN Document Server

    Cooray, A R; Cooray, Asantha; Farmer, Alison J.

    2003-01-01

    The occultation of background stellar sources by foreground Kuiper Belt Objects (KBOs) can be used to survey physical properties of the KBO population. We discuss statistics related to a KBO occultation survey, such as the event duration distribution, and suggest that occultation searches can be effectively used to probe the KBO size distribution below 10 km. In particular, we suggest that occultation surveys may be best suited to search for a turnover radius in the KBO size distribution due to collisions between small-size objects. For occultation surveys that monitor stellar sources near the ecliptic over a few square degrees, with time sampling intervals of order 0.1 sec and sensitivity to flux variations of a few percent or more, a turnover radius between 0.1 and 1.0 km can be probed. While occultation surveys will probe the low-radius limit and imaging surveys will detect KBOs of size 100 km or more, statistics of objects with sizes in the intermediate range of around 1 km to 100 km will likely remain un...

  20. Detecting Mass Loss in Main Belt Asteroids

    Science.gov (United States)

    Sandberg, Erik; Rajagopal, Jayadev; Ridgway, Susan E.; Kotulla, Ralf C.; Valdes, Francisco; Allen, Lori

    2016-01-01

    Sandberg, E., Rajagopal, J., Ridgway, S.E, Kotulla, R., Valdes, F., Allen, L.The Dark Energy Camera (DECam) on the 4m Blanco telescope at the Cerro Tololo Inter-American Observatory (CTIO) is being used for a survey of Near Earth Objects (NEOs). Here we attempt to identify mass loss in main belt asteroids (MBAs) from these data. A primary motivation is to understand the role that asteroids may play in supplying dust and gas for debris disks. This work focuses on finding methods to automatically pick out asteroids that have qualities indicating possible mass loss. Two methods were chosen: looking for flux above a certain threshold in the asteroid's radial profile, and comparing its PSF to that of a point source. After sifting through 490 asteroids, several have passed these tests and should be followed up with a more rigorous analysis.Sandberg was supported by the NOAO/KPNO Research Experience for Undergraduates (REU) Program which is funded by the National Science Foundation Research Experiences for Undergraduates Program (AST-1262829)

  1. Radiation belts study in RESONANCE project

    Science.gov (United States)

    Mogilevsky, Mikhail; Demekhov, Andrei; Zelenyi, Lev; Petrukovich, Anatoly; Shklyar, David

    The Earth’s inner magnetosphere is an important part of space weather framework. Outer radiation belt is a home for numerous communication and navigation satellites. But besides this practical problem, this region is a theoretical nugget. Hot magnetospheric, cold plas¬mospheric, and, in contrast, high energy plasma coexist here. Such non-equilibrium state of plasma is glued by various plasma oscillations actively interacting with particles and resulting, in particular, in spatial and velocity diffusion. Diffusion influences acceleration and precipitation of particles and defines their life¬time in the Earth’s magnetosphere. The project RESONANCE is aimed to study the whole complex of these issues, both practical (space weather), and fundamental (nonlinear plasma dynamics). The project RESONANCE is a part of the Russian Federal State Program. Lavochkin Association is responsi¬ble for preparation and testing of the satellites. Space Research Institute of the Russian Academy of Sciences is a leading scientific organization. Besides Russian scientists, specialists from Austria, Bulgaria, Czech Re¬public, Finland, France, Germany, Greece, Poland, Slovakia, Ukraine, USA take part.

  2. Role of dust direct radiative effect on the tropical rain belt over Middle East and North Africa: A high-resolution AGCM study

    Science.gov (United States)

    Bangalath, Hamza Kunhu; Stenchikov, Georgiy

    2015-05-01

    To investigate the influence of direct radiative effect of dust on the tropical summer rain belt across the Middle East and North Africa (MENA), the present study utilizes the high-resolution capability of an Atmospheric General Circulation Model, the High-Resolution Atmospheric Model. Ensembles of Atmospheric Model Intercomparison Project style simulations have been conducted with and without dust radiative impacts, to differentiate the influence of dust on the tropical rain belt. The analysis focuses on summer season. The results highlight the role of dust-induced responses in global- and regional-scale circulations in determining the strength and the latitudinal extent of the tropical rain belt. A significant response in the strength and position of the local Hadley circulation is predicted in response to meridionally asymmetric distribution of dust and the corresponding radiative effects. Significant responses are also found in regional circulation features such as African Easterly Jet and West African Monsoon circulation. Consistent with these dynamic responses at various scales, the tropical rain belt across MENA strengthens and shifts northward. Importantly, the summer precipitation over the semiarid strip south of Sahara, including Sahel, increases up to 20%. As this region is characterized by the "Sahel drought," the predicted precipitation sensitivity to the dust loading over this region has a wide range of socioeconomic implications. Overall, the study demonstrates the extreme importance of incorporating dust radiative effects and the corresponding circulation responses at various scales, in the simulations and future projections of this region's climate.

  3. On-conveyor belt determination of ash in coal

    International Nuclear Information System (INIS)

    A laboratory feasibility study has been carried out on new and advanced neutron and gamma-ray analysis systems for the direct on-conveyor belt analysis of ash in coal without the need for sample by-lines. Such an analysis system could deliver the combined advantages of a direct on-conveyor configuration with new and accurate analysis techniques. An industry survey of 18 coal companies carried out in early 1996 indicated that accurate on-belt ash analysis is of the highest priority. Subsequent laboratory work has focussed on the investigation of methods with the potential for improving the accuracy of ash content measurement relative to existing on-belt ash analysers, the most widely-used of which are based on dual energy gamma-ray transmission (DUET), which is sensitive to variations in ash composition. The current work indicates that on-belt neutron/gamma-ray techniques combined with advanced spectral analysis techniques show promise for development into an on-belt ash analysis system which is significantly less sensitive to composition changes than DUET and which analyses a much larger proportion of coal on the belt, thus eliminating some key sources of analysis error

  4. Forming the Cold Classical Kuiper Belt in a light Disk

    CERN Document Server

    Shannon, Andrew; Lithwick, Yoram

    2015-01-01

    Large Kuiper Belt Objects are conventionally thought to have formed out of a massive planetesimal belt that is a few thousand times its current mass. Such a picture, however, is incompatible with multiple lines of evidence. Here, we present a new model for the conglomeration of Cold Classical Kuiper belt objects, out of a solid belt only a few times its current mass, or a few percent of the solid density in a Minimum Mass Solar Nebula. This is made possible by depositing most of the primordial mass in grains of size centimetre or smaller. These grains collide frequently and maintain a dynamically cold belt out of which large bodies grow efficiently: an order-unity fraction of the solid mass can be converted into large bodies, in contrast to the ~0.1% efficiency in conventional models. Such a light belt may represent the true outer edge of the Solar system, and it may have effectively halted the outward migration of Neptune. In addition to the high efficiency, our model can also produce a mass spectrum that pe...

  5. Pearl southern highbush blueberry

    Science.gov (United States)

    The USDA-ARS Southern Horticulture has developed and released a new productive early ripening southern highbush blueberry cultivar, Pearl. 'Pearl', tested as MS 812, came from the cross Bluecrisp X Magnolia. The pedigree of Bluecrisp is unknown but it was tested as Fla 84-40, and Magnolia came fr...

  6. The relation of the mid-Tertiary coastal magmatic belt in south-central Chile to the late Oligocene increase in plate convergence rate

    Directory of Open Access Journals (Sweden)

    Jorge Muñoz

    2000-12-01

    Full Text Available The mid-Tertiary Coastal Magmatic Belt in south-central Chile, which crops out both in the Central Valley and, south of 41°S, in the Coastal Cordillera as far west as the Pacific coast, formed when the locus of Andean magmatic activity expanded, both to the west and to the east relative to its previous and current location in the Main Cordillera. This expansion of the magmatic arc occurred in conjunction with a regionally widespread episode of late Oligocene to Miocene extension which thinned the crust below the proto-Central Valley in south-central Chile and generated sedimentary basins west of, within, and east of the Main Cordillera. The extrusive rocks of the mid-Tertiary Coastal Magmatic Belt are interbedded with the late Oligocene to Miocene continental and marine sediments deposited in these basins, and forty-seven of the fifty new and previously published age determinations for these rocks are within the time period 29 Ma (late Oligocene to 18.8 Ma (early Miocene. The initiation of extension, basin formation and the westward migration of magmatic activity coincides closely to the beginning, in the late Oligocene, of the current period of both high convergence rate (>10 cm/yr and less oblique convergence, which together resulted in an approximately three-fold increase in trench-normal convergence rate between the Nazca and South American plates. Extension continued, along with a transient steepening of subduction angle as indicated by the westward migration of the volcanic front during the formation of the mid-Tertiary Coastal Magmatic Belt, during an approximately 10 million year period after the trench-normal convergence rate tripled across the Nazca and South American plate boundary. The mid-Tertiary Coastal Magmatic Belt includes igneous rocks chemically similar to modern Andean arc magmas, as well as rocks with ocean island basalt chemical affinities characterised by lower Ba/La (+5. The latter formed by melting of mantle

  7. Changes in the width of the tropical belt due to simple radiative forcing changes in the GeoMIP simulations

    Science.gov (United States)

    Davis, Nicholas A.; Seidel, Dian J.; Birner, Thomas; Davis, Sean M.; Tilmes, Simone

    2016-08-01

    Model simulations of future climates predict a poleward expansion of subtropical arid climates at the edges of Earth's tropical belt, which would have significant environmental and societal impacts. This expansion may be related to the poleward shift of the Hadley cell edges, where subsidence stabilizes the atmosphere and suppresses precipitation. Understanding the primary drivers of tropical expansion is hampered by the myriad forcing agents in most model projections of future climate. While many previous studies have examined the response of idealized models to simplified climate forcings and the response of comprehensive climate models to more complex climate forcings, few have examined how comprehensive climate models respond to simplified climate forcings. To shed light on robust processes associated with tropical expansion, here we examine how the tropical belt width, as measured by the Hadley cell edges, responds to simplified forcings in the Geoengineering Model Intercomparison Project (GeoMIP). The tropical belt expands in response to a quadrupling of atmospheric carbon dioxide concentrations and contracts in response to a reduction in the solar constant, with a range of a factor of 3 in the response among nine models. Models with more surface warming and an overall stronger temperature response to quadrupled carbon dioxide exhibit greater tropical expansion, a robust result in spite of inter-model differences in the mean Hadley cell width, parameterizations, and numerical schemes. Under a scenario where the solar constant is reduced to offset an instantaneous quadrupling of carbon dioxide, the Hadley cells remain at their preindustrial width, despite the residual stratospheric cooling associated with elevated carbon dioxide levels. Quadrupled carbon dioxide produces greater tropical belt expansion in the Southern Hemisphere than in the Northern Hemisphere. This expansion is strongest in austral summer and autumn. Ozone depletion has been argued to cause

  8. Petrogenesis and tectonic setting of the mafic-ultramafic rock association from NW Senja, West Troms Basement Complex

    OpenAIRE

    Priyatkina, Nadezda

    2013-01-01

    The studied mafic-ultramafic rock association occurs within Archean tonalitic gneisses and metasupracrustal suites of the Astridal belt belonging to the West Troms Basement Complex in the northwestern part of the Senja Island. The rock association appears in lens-shaped bodies, up to 200 m long, which are oriented conformal to the major metamorphic fabric of the host rock. The rock association is made up by interlayered units of green spinel-bearing olivine orthopyroxene-hornblendite, hornble...

  9. Earthquake scenario in West Bengal with emphasis on seismic hazard microzonation of the city of Kolkata, India

    OpenAIRE

    Nath, S K; M. D. Adhikari; S. K. Maiti; N. Devaraj; Srivastava, N; Mohapatra, L. D.

    2014-01-01

    Seismic microzonation is a process of estimating site-specific effects due to an earthquake on urban centers for its disaster mitigation and management. The state of West Bengal, located in the western foreland of the Assam–Arakan Orogenic Belt, the Himalayan foothills and Surma Valley, has been struck by several devastating earthquakes in the past, indicating the need for a seismotectonic review of the province, especially in light of probable seismic threat to its capital...

  10. Southern Taiwan - an Evolving "Coastal Range"?

    Science.gov (United States)

    Wu, F. T.; McIntosh, K.; Lavier, L. L.

    2008-12-01

    As a part of the TAIGER research, existing tectonic concepts are continuously being reviewed in light of new data and for experimental design. One of the critical areas for understanding the tectonics of Taiwan is southern Taiwan. Seismicity and recent tomographic imaging confirm that the tectonics of Taiwan is controlled by the subduction and collision of two plates: the Philippine Sea plate (PSP) and the Eurasian plate (EUR). In northern and central Taiwan the PSP is in collision with EUR, and at the same time subducts northward under northern Taiwan [Wu et al., 2008]. Before the PSP subducts to sufficient depth, the collision of PSP and EUR produced the Foothills and the Central Range on the EUR and the Coastal Range on the PSP side. For southern Taiwan, with 22.7°N as a rough demarcation, the tectonic interpretation is at variance and still in debate. To the east of southern Taiwan the inactive andesitic volcanic islands of Lutao and Lanhsu mark the top of the Luzon arc, separated from Taiwan by a somewhat deformed fore-arc basin [McIntosh et al., 2005]. To its west the Manila Trench is the western limit of a series of trend-parallel small thrusts on the ocean floor [Lunberg et al., 1997]. As the Trench approaches the continental shelf from the south it gradually loses its bathymetric signature. Southern Taiwan itself is commonly viewed as a part of the accretionary prism, and yet is also considered a continuation of the Central Range, produced by the collision of the Luzon arc and continental shelf. Suppe [1981] and many others had long recognized the central Taiwan orogeny, as a result of the collision of the Luzon Arc with the EUR continental shelf and Central Range, is built from rocks of the continental shelf. Inspection of a map of bathymetry around Taiwan shows that the continental shelf turns noticeably westward offshore of southwestern Taiwan, and that southern Taiwan is situated off the continental shelf. The presence of the Benioff zone under

  11. Vertical slip rates of active faults of southern Albania inferred from river terraces

    OpenAIRE

    Oswaldo Guzmán; Jean-Louis Mugnier; Riccardo Vassallo; Rexhep Koçi; François Jouanne

    2014-01-01

    Fluvial terraces of Shkumbin, Devoll, Osum and Vjosa rivers (southern Albania and northwestern Greece) are studied in order to quantify the vertical slip rates of the large active faults of the Dinaric-Albanic-Hellenic Alpine fold belt. The spatial and temporal variations of the incision rates along these rivers were estimated from the geomorphological mapping of the Quaternary sediments, the geometry and the dating of the terraces. Eleven terraces levels were identified in Albania from 68 ge...

  12. History of oceanic front development in the New Zealand sector of the Southern Ocean during the Cenozoic: a synthesis

    International Nuclear Information System (INIS)

    The New Zealand sector of the Southern Ocean (NZSSO) has opened about the Indian-Pacific spreading ridge throughout the Cenozoic. Today the NZSSO is characterised by broad zonal belts of antarctic (cold), subantarctic (cool), and subtropical (warm) surface-water masses separated by prominent oceanic fronts: the Subtropical Front (STF) c. 43 degrees S, Subantarctic Front (SAF) c. 50 degrees S, and Antarctic Polar Front (AAPF) c. 60 degrees S. Despite a meagre database, the broad pattern of Cenozoic evolution of these fronts is reviewed from the results of Deep Sea Drilling Project-based studies of sediment facies, microfossil assemblages and diversity, and stable isotope records, as well as from evidence in onland New Zealand Cenozoic sequences. Results are depicted schematically on seven paleogeographic maps covering the NZSSO at 10 m.y. intervals through the Cenozoic. During the Paleocene and most of the Eocene (65-35 Ma), the entire NZSSO was under the influence of warm to cool subtropical waters, with no detectable oceanic fronts. In the latest Eocene (c. 35 Ma), a proto-STF is shown separating subantarctic and subtropical waters offshore from Antarctica, near 65 degrees S paleolatitude. During the earliest Oligocene, this front was displaced northwards by development of an AAPF following major global cooling and biotic turnover associated with ice sheet expansion to sea level on East Antarctica. Early Oligocene full opening (c. 31 Ma) of the Tasmanian gateway initiated vigorous proto-circum-Antarctic flow of cold/cool waters, possibly through a West Antarctic seaway linking the southern Pacific and Atlantic Oceans, including detached northwards 'jetting' onto the New Zealand plateau where condensation and unconformity development was widespread in cool-water carbonate facies. Since this time, a broad tripartite division of antarctic, subantarctic, and subtropical waters has existed in the NZSSO, including possible development of a proto-SAF within the

  13. The outer boundary of radiation belts by the data of the ''Kosmos-426'' satellite

    International Nuclear Information System (INIS)

    Examined are the variations of the position of the external boundary of the radiation belts in magnetically calm periods as a function of the geomagnetic time MLT, orientation of the interplanetary magnetic field (IMF) and angle of slope of the geomagnetic dipole with respect to the Sun-Earth line. Experimental data have been obtained with the aid of the instrument which detected electrons with energies E > 20 keV on the ''Kosmos-426'' satellite during the period from 04.06.1971 to 3.01.1972. The effect of the angle of slope of the geomagnetic axis is maximum in after-midnight hours of MLT in the hemisphere with summer solstice. During the period of the northern orientation of the vertical component of IMF in almost all the MLT intervals, with the exception of after-midnight hours (2 to 8 hours MLT), the boundary is located at greater latitudes than in the southern orientation. The boundary correlates with the magnitude of the southern component of the IMF and does not correlate with the magnitude of the northern component of IMF

  14. Neoproterozoic Western Gondwana assembly and subduction-related plutonism: the role of the Rio Negro Complex in the Ribeira Belt, Brazil

    International Nuclear Information System (INIS)

    The assembly of Western Gondwana, during the Neoproterozoic, involved the Sao Francisco/West Congo Craton and its passive margins. The Ribeira Belt lies along the Brazilian Atlantic Coast and is one of the products of the super continent amalgamation. Collisional processes were preceded by subduction, recorded by the Rio Negro Complex orthogneisses at the Ribeira Belt. Its plutonites represent a gabbro-diorite-tonalite-throndhjemite plutonic series that evolved from 637 Ma (U-Pb zircon age of the tonalite gneiss) to nearly 600 Ma, at the beginning of the collisional event. Field, petrographic, litogeochemical, and isotopic characteristics of the Rio Negro Complex point to magmatism at a very mature oceanic arc or an immature continental crust as seen along attenuated passive margins. in the latter hypothesis, the margin could be related to a microplate or to the Congo/Angola Craton. (author)

  15. A study on energy gain on evacuated collector tube with cylindric absorber on building southern facade

    Energy Technology Data Exchange (ETDEWEB)

    Min Zijian [Information Engineering Coll., Capital Normal Univ., BJ (China); Ge Hongchuan [Beijing Eurocon Solar Energy Tech. Co., Ltd., BJ (China); Ma Yiqing [Special Education Coll. of Beijing Union Univ., BJ (China)

    2008-07-01

    According to the Clear-Day Model, daily energy gain and its annual variation of single evacuated collector tube with cylindric absorber in three different installation on building southern facade are studied. The solar energy gain of vertical installed tube and east-west horizontal installed tube comparing with local latitude tilted installed tube are presented. During the summer season the east-west horizontal installed tube has more solar energy gain than the vertical installed tube. (orig.)

  16. Delivery of meteorites from the asteroid belt

    Science.gov (United States)

    Nolan, Michael Craig

    The process of the delivery of meteorites to the surface of the Earth from plausible source regions such as the asteroid belt is currently understood in general terms, but important uncertainties and conflicts remain to be resolved. Stochastic effects of the rare disruptions of large asteroids on the population of meteorite-sized Earth-crossing asteroids can change the flux and the proportions of compositional types in the infalling meteorite population. These changes can be significant in magnitude over timescales of 108 years. Changes of the order of 1 percent can be expected on timescales of 105-106 y, consistent with small differences between the Antarctic meteorites and modern falls. The magnitude of changes depends strongly on poorly-understood details of collisions. Asteroids 961 Gaspra and 243 Ida were recently imaged by the Galileo spacecraft. I use a numerical hydrocode model to examine the outcomes of various sire impacts into targets the sizes of these asteroids. A shock wave fractures the asteroid in advance of crater excavation flow; thus, for impactors larger than 100 m, impacting at 5.3 km s-1, tensile strength is unimportant in these bodies, whether they are initially intact or are 'rubble piles'. Because of the shock-induced fracture, impact results are controlled by gravity. Therefore these asteroids are much more resistant to catastrophic disruption than predicted by previous estimates, which had assumed that strength was controlling these processes for rock targets. Fracture of km-size asteroids is different from fracture in terrestrial experiments using few-cm targets. The composition distribution of delivered meteorites depends on the outcomes of such asteroid impacts.

  17. Super-Comet or Big Asteroid Belt?

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1: Spectrograph of HD 69830 This graph of data from NASA's Spitzer Space Telescope demonstrates that the dust around a nearby star called HD 69830 (upper line) has a very similar composition to that of Comet Hale-Bopp. Spitzer spotted large amounts of this dust in the inner portion of the HD 69830 system. The bumps and dips seen in these data, or spectra, represent the 'fingerprints' of various minerals. Spectra are created when an instrument called a spectrograph spreads light out into its basic parts, like a prism turning sunlight into a rainbow. These particular spectra reveal the presence of the silicate mineral called olivine, and more specifically, a type of olivine called forsterite, which is pictured in the inset box. Forsterite is a bright-green gem found on Earth, on the 'Green Sand Beach' of Hawaii among other places; and in space, in comets and asteroids. Because the dust around HD 69830 has a very similar make-up to that of Comet Hale-Bopp, astronomers speculate that it might be coming from a giant comet nearly the size of Pluto. Such a comet may have been knocked into the inner solar system of HD 69830, where it is now leaving in its wake a trail of evaporated dust. Nonetheless, astronomers say the odds that Spitzer has caught a 'super-comet' spiraling in toward its star - an unusual and relatively short-lived event - are slim. Instead, they favor the theory that the observed dust is actually the result of asteroids banging together in a massive asteroid belt. The data of HD 69830's dust were taken by Spitzer's infrared spectrograph. The data of Comet Hale-Bopp were taken by the European Space Agency's Infrared Observatory Satellite. The picture of forsterite comes courtesy of Dr. George Rossman, California Institute of Technology, Pasadena.

  18. Meningococcal carriage in the African meningitis belt

    Science.gov (United States)

    2013-01-01

    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent the acquisition of pharyngeal carriage as well as invasive meningococcal disease and whether PsA-TT can prevent pharyngeal carriage needs to be determined. To address this issue, a consortium (the African Meningococcal Carriage (MenAfriCar) consortium) was established in 2009 to investigate the pattern of meningococcal carriage in countries of the African meningitis belt prior to and after the introduction of PsA-TT. This article describes how the consortium was established, its objectives and the standardised field and laboratory methods that were used to achieve these objectives. The experience of the MenAfriCar consortium will help in planning future studies on the epidemiology of meningococcal carriage in countries of the African meningitis belt and elsewhere. Un vaccin conjugué contenant un polysaccharide du sérogroupe A méningococcique et une anatoxine du tétanos (PsA-TT) (MenAfriVac™) est en cours de déploiement dans les pays de la ceinture africaine de la méningite. L’ expérience avec d’ autres vaccins conjugués polysaccharide/protéine a montré qu’ une partie importante de leur succès a été leur capacité à empêcher l’ acquisition du portage pharyngé et donc à arrêter la transmission et à induire une immunité de group. Si PsA-TT doit d’ atteindre l’ objectif de prévenir les épidémies, il devrait être en mesure d’ empêcher l’ acquisition du portage pharyngé ainsi que la méningococcie invasive et le fait que PsA-TT puisse emp

  19. Electrospun nanofiber belts made from high performance copolyimide

    International Nuclear Information System (INIS)

    Electrospun nanofibers based on copolyimides were made, aiming at finding a promising method for improving the mechanical properties of electrospun polyimide nanofibers. The copolyimide had a backbone consisting of 3,3',4,4'-biphenyl-tetracarboxylic dianhydride (BPDA), biphenylamide (BPA) and 4,4'-oxydianiline (ODA) residues. The structure and composition of the copolyimide was controlled by the ratio of rigid BPA and flexible ODA moieties. The electrospun copolyimide nanofibers were collected in the form of a belt using a rotating disc with a rim of 8 mm width. Scanning electron microscopy (SEM), infrared (IR) spectroscopy, x-ray scattering and tensile testing, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) were used to characterize the nanofiber belts. The nanofibers had a diameter range from 80 to 300 nm and were well aligned in the belts. The thermal stability of the nanofiber belts was over 460 deg. C. The tensile test showed that the copolyimide nanofiber belts had much better mechanical properties than either of the flexible and rigid homo-polyimide (homo-PI) nanofiber belts. The tensile strength, modulus and elongation to break of the copolyimide nanofiber belt with BPA/ODA ratio of 40/60 are respectively 1.1 ± 0.1 GPa, 6.2 ± 0.7 GPa and 20.8 ± 1.2%, compared to 459 ± 36 MPa, 2.1 ± 0.3 GPa and 41.3 ± 2.2% for BPDA/ODA homo-PI as well as 384 ± 18 MPa, 11.5 ± 0.6 GPa and 3.9 ± 0.1% for BPDA/BPA homo-PI. The important feature is that the electrospun polymer nanofibers can be made very strong by using copolyimides as spinning materials

  20. Flexural bending of southern Tibet in a retro foreland setting.

    Science.gov (United States)

    Wang, Erchie; Kamp, Peter J J; Xu, Ganqing; Hodges, Kip V; Meng, Kai; Chen, Lin; Wang, Gang; Luo, Hui

    2015-01-01

    The highest elevation of the Tibetan Plateau, lying 5,700 m above sea level, occurs within the part of the Lhasa block immediately north of the India-Tibet suture zone (Yarlung Zangbo suture zone, YZSZ), being 700 m higher than the maximum elevation of more northern parts of the plateau. Various mechanisms have been proposed to explain this differentially higher topography and the rock uplift that led to it, invoking crustal compression or extension. Here we present the results of structural investigations along the length of the high elevation belt and suture zone, which rather indicate flexural bending of the southern margin of the Lhasa block (Gangdese magmatic belt) and occurrence of an adjacent foreland basin (Kailas Basin), both elements resulting from supra-crustal loading of the Lhasa block by the Zangbo Complex (Indian plate rocks) via the Great Counter Thrust. Hence we interpret the differential elevation of the southern margin of the plateau as due originally to uplift of a forebulge in a retro foreland setting modified by subsequent processes. Identification of this flexural deformation has implications for early evolution of the India-Tibet continental collision zone, implying an initial (Late Oligocene) symmetrical architecture that subsequently transitioned into the present asymmetrical wedge architecture. PMID:26174578

  1. Geological characteristics of dike-structural belt in Taoshan orefield and its relationship to uranium deposits

    International Nuclear Information System (INIS)

    Taoshan uranium field is occurred in the Taoshan composite batholith in the central Jiangxi Province. The main body of the batholith was formed in Triassic-Early Cretaceous. In Late Cretaceous-Eogene, NE strike fault structure and dike belt were developed in the batholith. From the north to the south, there are successive Xiaobu-Matian dike-structural belt, Wangnitian dike- structural belt, Huangtan-Yueyuan dike-structural belt, Xibei-Shangluo dike-structural belt, Jipoling dike-structural belt, Wangce dike-structural belt and Shiyuanling dike-structural belt. These belts are controlled by the main fault, share the same space and similar time with the uranium mineralization, which is one of the important factors in positioning the uranium ore as well as the prospecting direction of exploration. (authors)

  2. On the behavior of site effects in Central Mexico (the Mexican Volcanic Belt – MVB), based on records of shallow earthquakes that occurred in the zone between 1998 and 2011

    OpenAIRE

    Clemente-Chavez, A.; Zúñiga, F. R.; Lermo, J.; A. Figueroa-Soto; Valdés, C.; M. Montiel; O. Chavez; Arroyo, M.

    2013-01-01

    The Mexican Volcanic Belt (MVB) is a seismogenic zone that transects the central part of Mexico with an east–west orientation. The risk and hazard seismic of this seismogenic zone has not been studied at detail due to the scarcity of instrumental data as well as because seismicity in the continental regimen of Central Mexico is not too frequent, however, it is known that there are precedents of large earthquakes (Mw > 6.0) that have taken place in this zone...

  3. PRESENTDAY STRESS STATE OF THE SHANXI TECTONIC BELT

    Directory of Open Access Journals (Sweden)

    Wang Kaiying

    2015-09-01

    Full Text Available The Shanxi tectonic belt is a historically earthquakeabundant area. For the majority of strong earthquakes in this area, the distribution of earthquake foci was controlled by the N–S oriented local structures on the tectonic belt. Studies of the present stress state of the Shanxi tectonic belt can contribute to the understanding of the relationship between strong earthquakes’ occurrence and their structural distribution and also facilitate assessments of regional seismic danger and determination of the regions wherein strong earthquakes may occur in future. Using the Cataclastic Analysis Method (CAM, we performed stress inversion based on the focal mechanism data of earthquakes which took place in the Shanxi tectonic belt from 1967 to 2010. Our results show that orientations of the maximum principal compressive stress axis of the Shanxi tectonic belt might have been variable before and after the 2001 Kunlun MS=8.1 strong earthquake, with two different superior trends of the NW–SE and NE–SW orientation in different periods. When the maximum principal compressive stress axis is oriented in the NE–SW direction, the pattern of the space distribution of the seismic events in the Shanxi tectonic belt shows a trend of their concentration in the N–S oriented tectonic segments. At the same time, the stress state is registered as horizontal shearing and horizontal extension in the N–S and NE–SW oriented local segments in turn. When the maximum principal compressive stress axis is NW–SE oriented, the stress state of the N–S and NE–SW oriented tectonic segments is primarily registered as horizontal shearing. Estimations of plunges of stress axes show that seismicity in the Shanxi belt  corresponds primarily to the activity of lowangle faults, and highangle stress sites are located in the NE–SW oriented extensional tectonic segments of the Shanxi belt. This indicates that the stress change of the Shanxi belt is

  4. West Bank and Gaza : Teachers

    OpenAIRE

    World Bank, (WB)

    2010-01-01

    The West Bank and Gaza is focusing on strengthening its education system: provision of schooling is relatively equitable and increased decentralization is planned. West Bank & Gaza (WB&G) spent 1.3 percent on public education as a percentage of Gross Domestic Product (GDP). This year, the Palestinian Authority (PA) published a report entitled Homestretch to Freedom, which outlines the obj...

  5. Rotationally driven 'zebra stripes' in Earth's inner radiation belt.

    Science.gov (United States)

    Ukhorskiy, A Y; Sitnov, M I; Mitchell, D G; Takahashi, K; Lanzerotti, L J; Mauk, B H

    2014-03-20

    Structured features on top of nominally smooth distributions of radiation-belt particles at Earth have been previously associated with particle acceleration and transport mechanisms powered exclusively by enhanced solar-wind activity. Although planetary rotation is considered to be important for particle acceleration at Jupiter and Saturn, the electric field produced in the inner magnetosphere by Earth's rotation can change the velocity of trapped particles by only about 1-2 kilometres per second, so rotation has been thought inconsequential for radiation-belt electrons with velocities of about 100,000 kilometres per second. Here we report that the distributions of energetic electrons across the entire spatial extent of Earth's inner radiation belt are organized in regular, highly structured and unexpected 'zebra stripes', even when the solar-wind activity is low. Modelling reveals that the patterns are produced by Earth's rotation. Radiation-belt electrons are trapped in Earth's dipole-like magnetic field, where they undergo slow longitudinal drift motion around the planet because of the gradient and curvature of the magnetic field. Earth's rotation induces global diurnal variations of magnetic and electric fields that resonantly interact with electrons whose drift period is close to 24 hours, modifying electron fluxes over a broad energy range into regular patterns composed of multiple stripes extending over the entire span of the inner radiation belt. PMID:24646996

  6. Fall Protection Characteristics of Safety Belts and Human Impact Tolerance.

    Science.gov (United States)

    Hino, Yasumichi; Ohdo, Katsutoshi; Takahashi, Hiroki

    2014-08-23

    Many fatal accidents due to falls from heights have occurred at construction sites not only in Japan but also in other countries. This study aims to determine the fall prevention performance of two types of safety belts: a body belt(1)), which has been used for more than 40 yr in the Japanese construction industry as a general type of safety equipment for fall accident prevention, and a full harness(2, 3)), which has been used in many other countries. To determine human tolerance for impact trauma, this study discusses features of safety belts with reference(4-9)) to relevant studies in the medical science, automobile crash safety, and aircrew safety. For this purpose, simple drop tests were carried out in a virtual workplace to measure impact load, head acceleration, and posture in the experiments, the Hybrid-III pedestrian model(10)) was used as a human dummy. Hybrid-III is typically employed in official automobile crash tests (New Car Assessment Program: NCAP) and is currently recognized as a model that faithfully reproduces dynamic responses. Experimental results shows that safety performance strongly depends on both the variety of safety belts used and the shock absorbers attached onto lanyards. These findings indicate that fall prevention equipment, such as safety belts, lanyards, and shock absorbers, must be improved to reduce impact injuries to the human head and body during falls. PMID:25152087

  7. JOVIAN EARLY BOMBARDMENT: PLANETESIMAL EROSION IN THE INNER ASTEROID BELT

    Energy Technology Data Exchange (ETDEWEB)

    Turrini, D.; Coradini, A.; Magni, G., E-mail: diego.turrini@ifsi-roma.inaf.it [Istituto di Astrofisica e Planetologia Spaziali, INAF-IAPS, Via Fosso del Cavaliere 100, 00133, Rome (Italy)

    2012-05-01

    The asteroid belt is an open window on the history of the solar system, as it preserves records of both its formation process and its secular evolution. The progenitors of the present-day asteroids formed in the Solar Nebula almost contemporary to the giant planets. The actual process producing the first generation of asteroids is uncertain, strongly depending on the physical characteristics of the Solar Nebula, and the different scenarios produce very diverse initial size-frequency distributions (SFDs). In this work, we investigate the implications of the formation of Jupiter, plausibly the first giant planet to form, on the evolution of the primordial asteroid belt. The formation of Jupiter triggered a short but intense period of primordial bombardment, previously unaccounted for, which caused an early phase of enhanced collisional evolution in the asteroid belt. Our results indicate that this Jovian Early Bombardment caused the erosion or the disruption of bodies smaller than a threshold size, which strongly depends on the SFD of the primordial planetesimals. If the asteroid belt was dominated by planetesimals less than 100 km in diameter, the primordial bombardment would have caused the erosion of bodies smaller than 200 km in diameter. If the asteroid belt was instead dominated by larger planetesimals, the bombardment would have resulted in the destruction of bodies as big as 500 km.

  8. Structural observations and U-Pb mineral ages from igneous rocks at the Archaean-Palaeoproterozoic boundary in the Salahmi Schist Belt, central Finland: constraints on tectonic evolution

    Directory of Open Access Journals (Sweden)

    Pietikäinen, K.

    1999-06-01

    Full Text Available The study area in Vieremä, central Finland, contains part of Archaean-Palaeoproterozoic boundary. In the east, the area comprises Archaean gneiss and the Salahmi Schist Belt. The rocks of the schist belt are turbiditic metagreywackes, with well-preserved depositional structures, occurring as Proterozoic wedge-shaped blocks, and staurolite schists, the latter representing higher-strained and metamorphosed equivalents of the metagreywackes. In the west of the area there is an Archaean gneiss block, containing strongly elongated structures, and deformed Svecofennian supracrustal rocks, which are cut by deformed granitoids. These are juxtaposed with the schist belt. The boundaries of these tectonometamorphic blocks are narrow, highly strained mylonites and thrust zones. The metamorphic grade of the supracrustal rocks increases from east to west, the increase being stepwise across the mylonitic block boundaries. The rocks are more deformed from east to west with younger structures overprinting. In the staurolite schists of the Salahmi Schist Belt, the most prominent structure is a lineation (L2 that overprints the bedding and axial plane foliation. In Sorronmäki quarry, at the western boundary of the schist belt, this Palaeoproterozoic lineation dominates all the structures in tonalite gneiss, which gives a U-Pb age of 2731±6 Ma. Southeast of the quarry, at the same boundary, the Salahmi schists have been overturned towards the northeast, suggesting that the Archaean gneiss at Sorronmäki has been thrust towards the northeast over these rocks. In the western part of the study area, the Leppikangas granodiorite that intrudes the Svecofennian supracrustal rocks gives a U-Pb age of 1891+6 Ma. In the granodiorite, a strong lineation formed by the intersection of two foliations, which maybe L2 is associated with thrusting towards the northeast. The monazite age of the Archaean Sorronmäki gneiss is 1817+3 Ma, and the titanite age of the Svecofennian

  9. Hydrothermal Evolution of the Giant Cenozoic Kadjaran porphyry Cu-Mo deposit, Tethyan metallogenic belt, Armenia, Lesser Caucasus: mineral paragenetic, cathodoluminescence and fluid inclusion constraints

    Science.gov (United States)

    Hovakimyan, Samvel; Moritz, Robert; Tayan, Rodrik; Rezeau, Hervé

    2016-04-01

    The Lesser Caucasus belongs to the Central segment of the Tethyan metallogenic belt and it is a key area to understand the metallogenic evolution between the Western & Central parts of the Tethyan belt and its extension into Iran. Zangezur is the most important mineral district in the southernmost Lesser Caucasus. It is a component of the South Armenian block, and it was generated during the convergence and collision of the southern margin of the Eurasian plate and the northern margin of the Arabian plate, and terranes of Gondwana origin (Moritz et al., in press). The Zangezur ore district consists of the Tertiary Meghri-Ordubad composite pluton, which is characterized by a long-lasting Eocene to Pliocene magmatic, tectonic and metallogenic evolution. It hosts major porphyries Cu-Mo and epithermal Au - polymetallic deposits and occurrences, including the giant world class Kadjaran porphyry Cu-Mo deposit (2244 Mt reserves, 0.3% Cu, 0.05% Mo and 0.02 g/t Au). The Kadjaran deposit is hosted by a monzonite intrusion (31.83±0.02Ma; Moritz et al., in press). Detailed field studies of the porphyry stockwork and veins of the different mineralization stages, their crosscutting and displacement relationships and the age relationship between different paragenetic mineral associations were the criteria for distinction of the main stages of porphyry mineralization at the Kadjaran deposit. The economic stages being: quartz- molybdenite, quartz-molybdenite-chalcopyrite, and quartz-chalcopyrite. The main paragenetic association of the Kadjaran porphyry deposit includes pyrite, molybdenite, chalcopyrite, bornite, chalcocite, pyrrhotite, covellite, sphalerite, and galena. Recent field observations in the Kadjaran open pit revealed the presence of epithermal veins with late vuggy silica and advanced argillic alteration in the north-eastern and eastern parts of the deposit. They are distributed as separate veins and have also been recognized in re-opened porphyry veins and in

  10. Earthquakes in Southern California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — There have been many earthquake occurrences in Southern California. This set of slides shows earthquake damage from the following events: Imperial Valley, 1979,...

  11. European Southern Observatory

    CERN Multimedia

    1970-01-01

    Professor A. Blaauw, Director general of the European Southern Observatory, with George Hampton on his right, signs the Agreement covering collaboration with CERN in the construction of the large telescope to be installed at the ESO Observatory in Chile.

  12. Ebola in West Africa.

    Science.gov (United States)

    Raka, Lul; Guardo, Monica

    2015-03-15

    Ebola viral disease (EVD) is a severe and life-threatening disease. The current Ebola outbreak in West Africa entered its second year and is unprecedented because it is the largest one in history, involved urban centers and affected a large number of health care workers. It quickly escalated from medical into a humanitarian, social, economic, and security crisis. The primary pillars to prevent EVD are: early diagnosis, isolation of patients, contact tracing and monitoring, safe burials, infection prevention and control and social mobilization. The implementation of all these components was challenged in the field. Key lessons from this Ebola outbreak are that countries with weak health care systems can't withstand the major outbreaks; preparedness to treat the first confirmed cases is a national emergency; all control measures must be coordinated together and community engagement is the great factor to combat this disease. PMID:27275217

  13. Ebola in West Africa

    Directory of Open Access Journals (Sweden)

    Lul Raka

    2015-02-01

    Full Text Available Ebola viral disease (EVD is a severe and life-threatening disease. The current Ebola outbreak in West Africa entered its second year and is unprecedented because it is the largest one in history, involved urban centers and affected a large number of health care workers. It quickly escalated from medical into a humanitarian, social, economic, and security crisis. The primary pillars to prevent EVD are: early diagnosis, isolation of patients, contact tracing and monitoring, safe burials, infection prevention and control and social mobilization. The implementation of all these components was challenged in the field. Key lessons from this Ebola outbreak are that countries with weak health care systems can’t withstand the major outbreaks; preparedness to treat the first confirmed cases is a national emergency; all control measures must be coordinated together and community engagement is the great factor to combat this disease.

  14. West-Side Story

    Science.gov (United States)

    Marochnik, L. S.

    2005-12-01

    This paper deals with the history of Density-Wave Spiral Theories in the 1960s. The motivation to write the paper was the publication of two papers on the history of these theories (Pasha 2004a, b). Pasha's papers tell only a part of the story that took place on the Western side of the Iron Curtain in the 1960s. But giving only a part of the full story is a distortion of historical truth. Important work done on the Eastern side of the Iron Curtain is still little known in the West. In this paper, I fill the gaps and correct chronological inaccuracies in Pasha's story and mention facts that are still unknown (or little known) to the astronomical community in the West. I also give my recollection of the development of Density-Wave Spiral Theories in the 1960s. The paper gives examples of important results in the theory of density waves in galaxies that are mistakenly attributed to C. C. Lin, F. H. Shu, Y.Y. Lau, C. Yuan and others, meanwhile they were obtained earlier by L. Marochnik, A. Suchkov and others. Below is another example. Both "famous" paper of Lin, Yuan and Shu (1969) and Marochnik and Suchkov (1969a) have appeared simultaneously in March of 1969. Both papers dealt, in particular, with the comparison of theory with observations. However, in the frame of their WKB approximation, Lin, Yuan and Shu (1969) employed an incorrect approach. It was a direct consequence of Marochnik and Suchkov (1969a) analysis and led to the far-going consequences. The paper has been published at the http://arxiv.org/abs/astro-ph/0501170 web site.

  15. Zooplankton of West Madagascar

    Science.gov (United States)

    Bemiasa, John; Remanevy, Sitraka

    2014-05-01

    During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Zooplankton samples were collected with Hydrobios Multinet at all environmental stations ranging from 200 m depth to the surface. The Multinet was equipped with 5 nets for depth-stratified sampling. The nets were fitted with 180 µm mesh size and the water flow through the nets was measured. The Multinet was deployed and retrieved at a rate of ~ 1.5 m per second and was obliquely hauled. The five nets were triggered at the pre-selected depth intervals 0-25m, 25-50m, 50-80m, 80-120m and 120-200m. All samples were stored in marked bottles and preserved with buffered formaldehyde of 4% for further analysis. As results,the zooplankton abundance was influenced by physico-chemical factors. During the study period 34 Family of zooplankton were identified which are dominated by Copepoda (58,69%) followed by Radiolaria (12,06%), Appendicularia (6,47%), Sagitta (5,11%), Larvae (4,57%), Ostracoda (3,13%), pelagic Foraminifera (2,15%). Family of zooplankton with abundance sampling sites. The findings of the present study will help to improve the scientific knowledge of the marine ecosystem of the west coast of Madagascar.

  16. The Southern Tyrrhenian subduction system. Recent evolution and neotectonic implications

    Energy Technology Data Exchange (ETDEWEB)

    Argnani, A. [Consiglio Nazionale delle Ricerche, Bologna (Italy). Ist. per la Geologia Marina

    2000-06-01

    Geological and geophysical data have been integrated with the aim of presenting a new evolutionary model for the Southern Tyrrhenian (Mediterranean Sea) and adjacent regions. The Southern Tyrrhenian back arc basin opened within a plate convergence regime because of sinking slab was torn apart on either side in the last 2 Ma and this process controlled the neotectonic of the Southern Apennines - Tyrrhenian region. On the north-eastern side the slab broke off from NW to SE and this process triggered volcanism and NW-SE extension along the Eastern Tyrrhenian margin, and strike-slip tectonics along NW-SE trending faults in Northern Calabria (Italy). On the south-western side the slab broke off from W to E along the Aeolian Island alignment, although the tear has currently been reoriented along the favouring the NNW-SSE Malta escarpment. During its sinking the subducted slab also detected from the overriding plate, favouring the wedging of the asthenosphere between the two plates and the regional uplift of the Calabrian arc and surroundings. This regional uplift promoted gravitational instability within the orogenic wedge, particularly towards low topography areas; the large-scale sliding of the Calabrian arc towards the Ionian basin can be the Apennines can be related to accommodation of vertical motions within the fold-nd-thrust belt. The pattern of responsible for extensional earthquakes in Calabria and the Southern Apennines, whereas Africa plate convergence can account for compressional earthquakes in Sicily.

  17. K-Ar cooling age profile from Joinville massif (PR and SC, Brazil) and Dom Feliciano belt (SC, Brazil) - Tectonics entanglement

    International Nuclear Information System (INIS)

    A K-Ar cooling age profile using different minerals from metamorphic rocks of the Joinville Massif and Dom Feliciano Belt is presented. Three main geochronological domains are distinguishable, from NW to SE: 1) Northern part of the Joinville Massif (NJM); 2) Southern part of the Joinville Massif (SJM) and 3) Dom Feliciano Belt (DBF). Geochronological domains 1 and 3 yielded K-Ar values in the range 800-500 Ma and 700-500 Ma, respectively, which show a clear influence of the Brasiliano Cycle. The granulite terrain comprising the SMJ exhibits ages older than 1700 Ma, indicating that this area was cool during the Late Proterozoic Brasiliano Cycle. The SJM and NJM limit is marked by a rapid Transition from Early Proterozoic ages in the SJM to Late Proterozoic ages in the NJM. On the other hand the contact between the SJM and DFB is interpreted as a thrust at a high, relatively cool crustal level. (author)

  18. Late Mesozoic deformations of the Verkhoyansk-Kolyma orogenic belt, Northeast Russia

    Science.gov (United States)

    Fridovsky, Valery

    2016-04-01

    . The superimposed structures are recognized from the early cleavage deformations. Folds F3 are often chevron type, open or tight. D1, D2 and D3 deformations are coaxial. In the Late-Neocomian-Aptian the Kolyma-Omolon superterrane started moving to the west. As a result, the thrust faults were reactivated with sinistral strike-slip motions along fault planes. At that time, granitoids of the North and Transverse belts were emplaced in the northwestern part of the Kolyma-Omolon superterrane. The strike slip faults were associated with cross open folds. The postacrettionary stage is associated with the development of the Albian-Late Cretaceous Okhotsk-Chukotka subduction zone. During this stage strike-slip faults and associated deformation structures were superimposed upon accretion-related tectonic structures of the Verkhoyansk - Kolyma orogenic belt.

  19. FAQ: West Nile Virus and Dead Birds

    Science.gov (United States)

    ... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On this ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

  20. Psychological trauma and evidence for enhanced vulnerability for posttraumatic stress disorder through previous trauma among West Nile refugees

    OpenAIRE

    Karunakara Unni; Schauer Maggie; Neuner Frank; Klaschik Christine; Robert Christina; Elbert Thomas

    2004-01-01

    Abstract Background Political instability and the civil war in Southern Sudan have resulted in numerous atrocities, mass violence, and forced migration for vast parts of the civilian population in the West Nile region. High exposure to traumatic experiences has been particularly prominent in the Ugandan and Sudanese of the West Nile Region, representing an indication of the psychological strain posed by years of armed conflict. Methods In this study the impact of traumatic events on the preva...

  1. Lassa Virus Seroprevalence in Sibirilia Commune, Bougouni District, Southern Mali

    Science.gov (United States)

    Sogoba, Nafomon; Rosenke, Kyle; Adjemian, Jennifer; Diawara, Sory Ibrahim; Maiga, Ousmane; Keita, Moussa; Konaté, Drissa; Keita, Abdoul Salam; Sissoko, Ibrahim; Boisen, Matt; Nelson, Diana; Oottamasathien, Darin; Millett, Molly; Garry, Robert F.; Branco, Luis M.; Traoré, Sékou F.; Doumbia, Seydou; Feldmann, Heinz

    2016-01-01

    Lassa virus (LASV) is endemic to several nations in West Africa. In Mali, LASV was unknown until an exported case of Lassa fever was reported in 2009. Since that time, rodent surveys have found evidence of LASV-infected Mastomys natalensis rats in several communities in southern Mali, near the border with Côte d’Ivoire. Despite increased awareness, to date only a single case of Lassa fever has been confirmed in Mali. We conducted a survey to determine the prevalence of LASV exposure among persons in 3 villages in southern Mali where the presence of infected rodents has been documented. LASV IgG seroprevalence ranged from 14.5% to 44% per village. No sex bias was noted; however, seropositivity rates increased with participant age. These findings confirm human LASV exposure in Mali and suggest that LASV infection/Lassa fever is a potential public health concern in southern Mali. PMID:26981786

  2. Isotopic geochronological evidence for the Paleoproterozoic age of gold mineralization in Archean greenstone belts of Karelia, the Baltic Shield

    Science.gov (United States)

    Larionova, Yu. O.; Samsonov, A. V.; Shatagin, K. N.; Nosova, A. A.

    2013-09-01

    The Rb-Sr age of metasomatic rocks from four gold deposits and occurrences localized in Archean granite-greenstone belts of the western, central, and southern Karelian Craton of the Baltic Shield has been determined. At the Pedrolampi deposit in central Karelia, the dated Au-bearing beresite and quartz-carbonate veins are located in the shear zone and replace Mesoarchean (˜2.9 Ga) mafic and felsic metavolcanic rocks of the Koikar-Kobozero greenstone belt. At the Taloveis ore occurrence in the Kostomuksha greenstone belt of western Karelia, the dated beresite replaces Neoarchean (˜2.7 Ga) granitoids and is conjugated with quartz veins in the shear zone. At the Faddeinkelja occurrence of southern Karelia, Aubearing beresite in the large tectonic zone, which transects Archean granite and Paleoproterozoic mafic dikes, has been studied. At the Hatunoja occurrence in the Jalonvaara greenstone belt of southwestern Karelia, the studied quartz veins and related gold mineralization are localized in Archean granitoids. The Rb-Sr isochrons based on whole-rock samples and minerals from ore-bearing and metasomatic wall rocks and veins yielded ˜1.7 Ga for all studied objects. This age is interpreted as the time of development of ore-bearing tectonic zones and ore-forming hydrothermal metasomatic alteration. New isotopic data in combination with the results obtained by our precursors allow us to recognize the Paleoproterozoic stage of gold mineralization in the Karelian Craton. This stage was unrelated to the Archean crust formation in the Karelian Block and is a repercussion of the Paleoproterozoic (2.0-1.7 Ga) crust-forming tectonic cycle, which gave rise to the formation of the Svecofennian and Lapland-Kola foldbelts in the framework of the Karelain Craton. The oreforming capability of Paleoproterozoic tectonics in the Archean complexes of the Karelian Craton was probably not great, and its main role consisted in reworking of the Archean gold mineralization of various

  3. Gravity inferred subsurface structure of Gadwal Schist belt, Andhra Pradesh

    Indian Academy of Sciences (India)

    G Ramadass; I B Ramaprasada Rao; N Srinivasulu

    2001-03-01

    Detailed gravity data collected across the Gadwal schist belt in the state of Andhra Pradesh show an 8.4 mgal residual gravity anomaly associated with meta-sediments/volcanics of the linear NNW-SSE trending schist belt that shows metamorphism from green schist to amphibolite facies. This schist belt is flanked on either side by the peninsular gneissic complex. The elevation and slab Bouguer corrected residual gravity profile data were interpreted using 2-D prism models. The results indicate a synformal structure having a width of 1.8 km at the surface, tapering at a depth of about 2.6 km with a positive density contrast of 0.15 gm/cc with respect to the surrounding peninsular gneissic complex.

  4. Regional Fault Systems of Qaidam Basin and Adjacent Orogenic Belts

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The purpose of this paper is to analyze the regional fault systems of Qaidam basin and adjacent orogenic belts. Field investigation and seismic interpretation indicate that five regional fault systems occurred in the Qaidam and adjacent mountain belts, controlling the development and evolution of the Qaidam basin. These fault systems are: (1)north Qaidam-Qilian Mountain fault system; (2) south Qaidam-East Kunlun Mountain fault system; (3)Altun strike-slip fault system; (4)Elashan strike-slip fault system, and (5) Gansen-Xiaochaidan fault system. It is indicated that the fault systems controlled the orientation of the Qaidam basin, the formation and distribution of secondary faults within the basin,the migration of depocenters and the distribution of hydrocarbon accumulation belt.

  5. TAKRAF belt conveyors - effective means of transport for bulk materials

    Energy Technology Data Exchange (ETDEWEB)

    Peterman, L.

    1988-11-01

    Presents belt conveyor types produced by TAKRAF, especially those intended for use at surface mines. The FAM works (Transport Equipment) produces belt conveyors 800-1,400 mm wide, with 2.09-5.24 m/s belt velocity, 460-3,750 m/sup 3//h capacity, max. feed distance 2,500 m and (1-5)x55 kW drive power. The drive stations are based on pontoons or caterpillar vehicles while the end-stations are based on pontoons. Charging hoppers have autonomic drives and are mobile on rail. The described conveyors can also be used in power plants. The FAM works produces 650-800 mm wide conveyors for thermal electric power stations. The conveyors are equipped with metal detectors and metal separators.

  6. Relativistic surfatron process for Landau resonant electrons in radiation belts

    CERN Document Server

    Osmane, A

    2014-01-01

    Recent theoretical studies of the nonlinear wave-particle interactions for relativistic particles have shown that Landau resonant orbits could be efficiently accelerated along the mean background magnetic field for propagation angles $\\theta$ in close proximity to a critical propagation $\\theta_\\textrm{c}$ associated with a Hopf--Hopf bifurcation condition. In this report, we extend previous studies to reach greater modeling capacities for the study of electrons in radiation belts by including longitudinal wave effects and inhomogeneous magnetic fields. We find that even though both effects can limit the surfatron acceleration of electrons in radiation belts, gains in energy of the order of 100 keV, taking place on the order of ten milliseconds, are sufficiently strong for the mechanism to be relevant to radiation belt dynamics.

  7. An interpretation of the aeromagnetic data covering portion of the Damara orogenic belt, with special reference to the occurrence of uraniferous granite

    International Nuclear Information System (INIS)

    This thesis comprises primarily palaeomagnetic studies within the Damara orogenic belt of South West Africa (Namibia), as well as an interpretation of the regional structure, utilizing published aeromagnetic data. The prime objectives of the study were to aid uranium exploration programmes in this area by establishing any possible magnetic relationships associated with the uraniferous granites in the area, and to interpret regional structure from the aeromagnetic data. Cursory interpretation of the airborne radiometric data is also undertaken. Gravity traverses, conducted across three dome structures with which uranium mineralisation is intimately associated, are interpreted in order to determine the origin of these structures

  8. Seismicity in northeast edge of the Mexican Volcanic Belt (MVB), activation of an undocumented fault: the Peñamiller earthquake sequence of 2011, Queretaro, Mexico

    OpenAIRE

    Clemente-Chavez, A.; A. Figueroa-Soto; Zúñiga, F. R.; Arroyo, M.; M. Montiel; O. Chavez

    2013-01-01

    The Peñamiller town, in the Queretaro state, Mexico is located at the northeast border of the seismogenic zone known as the Mexican Volcanic Belt (MVB), which covers a central fringe of Mexico with east-west orientation. In this town, a sequence of small earthquakes occurred during the end of 2010 and beginning of 2011. Seismicity frequent in of the continental regimen of central Mexico are not common, however, it is known that there are precedents of large earthquakes (Mw m...

  9. The Cenozoic fold-and-thrust belt of Eastern Sardinia: Evidences from the integration of field data with numerically balanced geological cross section

    Science.gov (United States)

    Arragoni, S.; Maggi, M.; Cianfarra, P.; Salvini, F.

    2016-06-01

    Newly collected structural data in Eastern Sardinia (Italy) integrated with numerical techniques led to the reconstruction of a 2-D admissible and balanced model revealing the presence of a widespread Cenozoic fold-and-thrust belt. The model was achieved with the FORC software, obtaining a 3-D (2-D + time) numerical reconstruction of the continuous evolution of the structure through time. The Mesozoic carbonate units of Eastern Sardinia and their basement present a fold-and-thrust tectonic setting, with a westward direction of tectonic transport (referred to the present-day coordinates). The tectonic style of the upper levels is thin skinned, with flat sectors prevailing over ramps and younger-on-older thrusts. Three regional tectonic units are present, bounded by two regional thrusts. Strike-slip faults overprint the fold-and-thrust belt and developed during the Sardinia-Corsica Block rotation along the strike of the preexisting fault ramps, not affecting the numerical section balancing. This fold-and-thrust belt represents the southward prosecution of the Alpine Corsica collisional chain and the missing link between the Alpine Chain and the Calabria-Peloritani Block. Relative ages relate its evolution to the meso-Alpine event (Eocene-Oligocene times), prior to the opening of the Tyrrhenian Sea (Tortonian). Results fill a gap of information about the geodynamic evolution of the European margin in Central Mediterranean, between Corsica and the Calabria-Peloritani Block, and imply the presence of remnants of this double-verging belt, missing in the Southern Tyrrhenian basin, within the Southern Apennine chain. The used methodology proved effective for constraining balanced cross sections also for areas lacking exposures of the large-scale structures, as the case of Eastern Sardinia.

  10. Assessment of Undiscovered Oil and Gas Resources of the West Siberian Basin Province, Russia, 2008

    Science.gov (United States)

    Schenk, Christopher J.; Bird, Kenneth J.; Charpentier, Ronald R.; Gautier, Donald L.; Houseknecht, David W.; Klett, Timothy R.; Moore, Thomas E.; Pawlewicz, Mark J.; Pitman, Janet K.; Tennyson, Marilyn E.

    2008-01-01

    The U.S. Geological Survey (USGS) recently assessed the undiscovered oil and gas potential of the West Siberian Basin Province in Russia as part of the USGS Circum-Arctic Resource Appraisal program. This province is the largest petroleum basin in the world and has an areal extent of about 2.2 million square kilometers. It is a large rift-sag feature bounded to the west by the Ural fold belt, to the north by the Novaya Zemlya fold belt and North Siberian Sill, to the south by the Turgay Depression and Altay-Sayan fold belt, and to the east by the Yenisey Ridge, Turukhan-Igarka uplift, Yenisey-Khatanga Basin, and Taimyr High. The West Siberian Basin Province has a total discovered oil and gas volume of more than 360 billion barrels of oil equivalent (Ulmishek, 2000). Exploration has led to the discovery of tens of giant oil and gas fields, including the Urengoy gas field with more than 3500 trillion cubic feet of gas reserves and Samotlar oil field with reserves of nearly 28 billion barrels of oil (Ulmishek, 2003). This report summarizes the results of a reassessment of the undiscovered oil and gas potential of that part of the province north of the Arctic Circle; a previous assessment that included the entire province was completed in 2000 (Ulmishek, 2000). The total petroleum system (TPS) and assessment units (AU) defined by the USGS for the assessments in 2000 were adopted for this assessment. However, only those parts of the Aus lying wholly or partially north of the Arctic Circle were assessed for this study.

  11. Emplacement and reworking of the Marampa Group allothchon, northwestern Sierra Leone, West Africa

    Science.gov (United States)

    Latiff, R. S. A.; Andrews, J. R.; Wright, L. I.

    1997-10-01

    The structural evolution and relative age of the Precambrian Marampa Group, a 60 km wide north-northwest trending fold thrust belt is described in detail. The Marampa Group is shown to be unconformably overlain by the Rokel River Group which lies immediately to the east and is separated by a major crustal shear zone from gneisses and amphibolites of the Kasila Group to the west. Previous workers have interpreted the fold thrust belt as a klippe of the adjacent Kasila Group derived from the west or as an autochthonous volcano-sedimentary deposit engulfed by granitic. basement. Ages ranging from 500 to > 2700 Ma have been suggested. Evidence is presented to show that the important deformation of the Marampa Group clearly predates the deposition of the Rokel River Group and must represent a significant earlier orogenic event. Constraints on the relationship of this older deformation to the 2700-2750 Ma deformation of the Kasila Group are discussed. The earliest structures consist of flat lying thrusts which transported Marampa Group metasediments, with or without their basal metavolcanic formation, eastward from their source basin over the basin margin and onto a flanking heterogeneously deformed older granitic gneiss basement. Subsequent intrusion of megacrystic, now porphiyroclastic granites was followed by a major period of crustal extension during which sediments and volcanics of the Rokel River Group were deposited in rift basins. Renewed east-west crustal shortening ascribed to the Pan-African event inverted earlier extensional structures thrusting the Rokel River Group westward over -the Marampa Group and leading to local facing confrontations where east dipping faults were reactivated. The relationship of the Marampa Group to the greenstone belts of Guinea, Liberia and Sierra Leone remains unresolved.

  12. The Belt voice: Acoustical measurements and esthetic correlates

    Science.gov (United States)

    Bounous, Barry Urban

    This dissertation explores the esthetic attributes of the Belt voice through spectral acoustical analysis. The process of understanding the nature and safe practice of Belt is just beginning, whereas the understanding of classical singing is well established. The unique nature of the Belt sound provides difficulties for voice teachers attempting to evaluate the quality and appropriateness of a particular sound or performance. This study attempts to provide answers to the question "does Belt conform to a set of measurable esthetic standards?" In answering this question, this paper expands on a previous study of the esthetic attributes of the classical baritone voice (see "Vocal Beauty", NATS Journal 51,1) which also drew some tentative conclusions about the Belt voice but which had an inadequate sample pool of subjects from which to draw. Further, this study demonstrates that it is possible to scientifically investigate the realm of musical esthetics in the singing voice. It is possible to go beyond the "a trained voice compared to an untrained voice" paradigm when evaluating quantitative vocal parameters and actually investigate what truly beautiful voices do. There are functions of sound energy (measured in dB) transference which may affect the nervous system in predictable ways and which can be measured and associated with esthetics. This study does not show consistency in measurements for absolute beauty (taste) even among belt teachers and researchers but does show some markers with varying degrees of importance which may point to a difference between our cognitive learned response to singing and our emotional, more visceral response to sounds. The markers which are significant in determining vocal beauty are: (1) Vibrancy-Characteristics of vibrato including speed, width, and consistency (low variability). (2) Spectral makeup-Ratio of partial strength above the fundamental to the fundamental. (3) Activity of the voice-The quantity of energy being produced. (4

  13. Structural framework of the Zagros Fold-Thrust Belt, Iran

    Energy Technology Data Exchange (ETDEWEB)

    Sepehr, M.; Cosgrove, J.W. [Imperial College, London (United Kingdom). Royal School of Mines

    2004-08-01

    Data gleaned from the literature on the Zagros have been compiled and used in conjunction with new interpretations to provide a better picture of the structures, sedimentation history and deformation of this hydrocarbon rich Mountain Belt. The belt parallel Mountain Front, the N-S trending Kazerun, lzeh and E-W trending Bala Rud Fault Zones are defined as the master structural elements of the Belt. These fault zones divide the Zagros basin into zones with different stratigraphic successions and different rheological profiles. This resulted in different structural styles developing along the belt during the subsequent collision. The Kazerun and lzeh Fault Zones acted as the depositional system transition zone between the Lurestan and Fars regions in Jurassic-Cretaceous time and partly controlled the distribution of the Kazhdumi Formation (one of the major source rocks). By the end of the Cretaceous the NW-SE trending Mountain Front Fault divided the present Folded Belt of the Zagros into a major foreland basin to the southwest, and a piggyback basin to the northeast. Activity along other major (transfer) fault zones including the lzeh, Kazerun and Bala Rud Fault zones occurred at this time and controlled the sedimentation and subsidence of the Dezful Embayment the main target region for hydrocarbon exploration. These fault zones controlled the thickness of the Asmari Formation (one of the main reservoirs) and also the considerable thickness and facies changes of the Gachsaran Formation (the major seal to the Asmari Formation). The present morphology of the mountain belt is interpreted as being mainly related to the pinning of the Mountain Front Fault to the northwest of the Dezful Embayment and to the north of the Strait of Hormuz. (author)

  14. Pn anisotropic tomography under the entire Tienshan orogenic belt

    Science.gov (United States)

    Zhou, Zhigang; Lei, Jianshe

    2015-11-01

    We present a new anisotropic tomography of the uppermost mantle under the Tienshan orogenic belt and surrounding regions using a number of Pn arrival-time data hand-picked from portable seismic stations and chosen from the Xinjiang provincial observation bulletins and the EHB datasets. Our results exhibit prominent lateral heterogeneities in the study region. Distinct low-velocity anomalies are visible under the tectonically active regions, such as the Tienshan orogenic belt and western Kunlun Mountains, whereas pronounced high-velocity anomalies are imaged beneath the stable blocks, such as the Kazakh shield, the Junggar, Tarim, Qaidam, and Turpan-Hami basins, and the Tajik depression. Most strong earthquakes (Ms > 7.0) are mainly distributed along the transition zone of high to low velocity anomalies, suggesting a possible correlation between the strong earthquakes and the upper mantle structure. The fast directions of Pn anisotropy beneath the Tienshan orogenic belt are generally parallel to its striking orientation, whereas those beneath Pamir show a northward arc-shaped distribution. The Pn fast-velocity directions on the boundaries of the Kazakh shield and the Tarim and Junngar basins are approximately perpendicular to the strike of the Tienshan orogenic belt. By integrating with previous findings, our results suggest that the Tarim and Kazakh lithospheric materials could have underthrusted beneath the Tienshan orogenic belt that leads to the hot mantle material upwelling under the Tienshan orogenic belt, which is attributable to the Indo-Asian collision. These dynamic processes could play important roles in the Tienshan mountain building.

  15. Searching for Chips of Kuiper Belt Objects in Meteorites

    Science.gov (United States)

    Zolensky, M. E.; Ohsumi, K.; Briani, G.; Gounelle, M.; Mikouchi, T.; Satake, W.; Kurihara, T.; Weisberg, M. K.; Le, L.

    2009-01-01

    The Nice model [1&2] describes a scenario whereby the Jovian planets experienced a violent reshuffling event approx.3:9 Ga the giant planets moved, existing small body reservoirs were depleted or eliminated, and new reservoirs were created in particular locations. The Nice model quantitatively explains the orbits of the Jovian planets and Neptune [1], the orbits of bodies in several different small body reservoirs in the outer solar system (e.g., Trojans of Jupiter [2], the Kuiper belt and scattered disk [3], the irregular satellites of the giant planets [4], and the late heavy bombardment on the terrestrial planets approx.3:9 Ga [5]. This model is unique in plausibly explaining all of these phenomena. One issue with the Nice model is that it predicts that transported Kuiper Belt Objects (KBOs) (things looking like D class asteroids) should predominate in the outer asteroid belt, but we know only about 10% of the objects in the outer main asteroid belt appear to be D-class objects [6]. However based upon collisional modeling, Bottke et al. [6] argue that more than 90% of the objects captured in the outer main belt could have been eliminated by impacts if they had been weakly-indurated objects. These disrupted objects should have left behind pieces in the ancient regoliths of other, presumably stronger asteroids. Thus, a derived prediction of the Nice model is that ancient regolith samples (regolith-bearing meteorites) should contain fragments of collisionally-destroyed Kuiper belt objects. In fact KBO pieces might be expected to be present in most ancient regolith- bearing meteorites [7&8].

  16. Fall Protection Characteristics of Safety Belts and Human Impact Tolerance

    OpenAIRE

    HINO, Yasumichi; OHDO, Katsutoshi; Takahashi, Hiroki

    2014-01-01

    Abstract: Many fatal accidents due to falls from heights have occurred at construction sites not only in Japan but also in other countries. This study aims to determine the fall prevention performance of two types of safety belts: a body belt1 ), which has been used for more than 40 yr in the Japanese construction industry as a general type of safety equipment for fall accident prevention, and a full harness2, 3 ), which has been used in many other countries. To determine human tolerance for ...

  17. Bifurcation for Dynamical Systems of Planet-Belt Interaction

    OpenAIRE

    Jiang, Ing-Guey; Yeh, Li-Chin

    2002-01-01

    The dynamical systems of planet-belt interaction are studied by the fixed-point analysis and the bifurcation of solutions on the parameter space is discussed. For most cases, our analytical and numerical results show that the locations of fixed points are determined by the parameters and these fixed points are either structurally stable or unstable. In addition to that, there are two special fixed points: the one on the inner edge of the belt is asymptotically stable and the one on the outer ...

  18. Beach rocks of the central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Wagle, B.G.

    -an overview. Bulletin Deccan College Research Institute, Pune 44:153-163 Kumar S, Rao GV (1982) Geographical and Quaternary history of the west coast of Ratnagiri District, Maharashtra. First National Seminar Quaternary Environmental Papers. Marh 58 (ed) Hin... dustan Publication Company, Delhi, pp 311-318 Pascoe EH (1964) A Manual of the geology of India and Bunna. Goverment of India Press, New Delhi, 1906-1907, P Russel RJ, McIntire WG (1965) Southern hemisphere beach rock. 115 Indian Ocean Studies Technical...

  19. ARM West Antarctic Radiation Experiment (AWARE) Science Plan

    Energy Technology Data Exchange (ETDEWEB)

    Lubin, D [National Science Foundation; Bromwich, DH [Ohio State University; Russell, LM [Scripps Institution of Oceanography; Verlinde, J [The Pennsylvania State University; Vogelmann, AM [Brookhaven National Laboratory

    2015-10-01

    West Antarctica is one of the most rapidly warming regions on Earth, and this warming is closely connected with global sea level rise. The discovery of rapid climate change on the West Antarctic Ice Sheet (WAIS) has challenged previous explanations of Antarctic climate change that focused on strengthening of circumpolar westerlies in response to the positive polarity trend in the Southern Annular Mode. West Antarctic warming does not yet have a comprehensive explanation: dynamical mechanisms may vary from one season to the next, and these mechanisms very likely involve complex teleconnections with subtropical and tropical latitudes. The prime motivation for this proposal is that there has been no substantial atmospheric science or climatological field work on West Antarctica since the 1957 International Geophysical Year and that research continued for only a few years. Direct meteorological information on the WAIS has been limited to a few automatic weather stations for several decades, yet satellite imagery and meteorological reanalyses indicate that West Antarctica is highly susceptible to advection of warm and moist maritime air with related cloud cover, depending on the location and strength of low pressure cells in the Amundsen, Ross, and Bellingshausen Seas. There is a need to quantify the role of these changing air masses on the surface energy balance, including all surface energy components and cloud-radiative forcing. More generally, global climate model simulations are known to perform poorly over the Antarctic and Southern Oceans, and the marked scarcity of cloud information at southern high latitudes has so far inhibited significant progress. Fortunately, McMurdo Station, where the Atmospheric Radiation Measurement Facility’s (ARM’s) most advanced cloud and aerosol instrumentation is situated, has a meteorological relationship with the WAIS via circulation patterns in the Ross and Amundsen Seas. We can therefore gather sophisticated data with cloud

  20. Discovery of Enclaves from Cenozoic Pulu Volcanic Rocks in West Kunlun Mountains and Its Geological Implications

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper, we present the occurrence and mineral components of the enclaves firstly discovered in the Cenozoic Pulu volcanic rocks in west Kunlun Mountains, and propose that the enclave is accumulated by fractional crystallization within high-level magma chamber. In addition, the chemical compositions of its primary magma are calculated. The calculated compositions are similar to those of the Kangxiwa volcanic rocks that belong to the same volcanic belt in the Pulu volcanic region, suggesting their origin from the same source region. However, the temperatures and oxygen fugacity of magmas at high-level magma chamber decreased along with fractional crystallization.

  1. Late ordovician stratigraphy, zircon provenance and tectonics, Lachlan Fold Belt, southeastern Australia

    International Nuclear Information System (INIS)

    Ordovician quartz turbidites of the Lachlan Fold Belt in southeastern Australia accumulated in a marginal sea and overlapped an adjoining island arc (Molong volcanic province) developed adjacent to eastern Gondwana. The turbidite succession in the Shoalhaven River Gorge, in the southern highlands of New South Wales, has abundant outcrop and graptolite sites. The succession consists of, from the base up, a unit of mainly thick-bedded turbidites (undifferentiated Adaminaby Group), a unit with conspicuous bedded chert (Numeralla Chert), a unit with common thin-bedded turbidites [Bumballa Formation (new name)] and a unit of black shale (Warbisco Shale). Coarse to very coarse sandstone in the Bumballa Formation is rich in quartz and similar to sandstone in the undifferentiated Adaminaby Group. Detrital zircons from sandstone in the Bumballa Formation, and from sandstone at a similar stratigraphic level from the upper Adaminaby Group of the Genoa River area in eastern Victoria, include grains as young as 453-473 Ma, slightly older than the stratigraphic ages. The dominant detrital ages are in the interval 500-700 Ma (Pacific Gondwana component) with a lessor concentration of Grenville ages (1000-1300 Ma). This pattern resembles other Ordovician sandstones from the Lachlan Fold Belt and also occurs in Triassic sandstones and Quaternary sands from eastern Australia. The Upper Ordovician succession is predominantly fine grained, which reflects reduced clastic inputs from the source in the Middle Cambrian to earliest Ordovician Ross-Delamerian Fold Belts that developed along the eastern active margin of Gondwana. Development of subduction zones in the Late Ordovician marginal sea are considered to be mainly responsible for the diversion of sediment and the resulting reduction in the supply of terrigenous sand to the island arc and eastern part of the marginal sea. Sixty zircons from each sample were analysed and results are presented. Methods following standard procedures

  2. U-Pb SHRIMP and Sm-Nd geochronology of the Anapolis-Itaucu complex, Araxa group and associated granites: Neoproterozoic high grade metamorphism and magmatism in the Central part of the Brasilia Belt, Goias

    International Nuclear Information System (INIS)

    The Tocantins Province (Almeida et al. 1981) in central Brazil is a Neoproterozoic orogenic zone developed between the Amazon and Sao Francisco cratons and possibly a third continental block, known as Parapanema Block, hidden below the sedimentary rocks of the Parana Basin. The Tocantins Province comprises the eastward vergent Brasilia Belt, adjacent to the Sao Francisco Craton (Marini et al. 1984), and the westward vergent Paraguay and Araguaia belts, developed on the eastern margin of the Amazon Craton. According to Trompette (1997), the Brasilia and Araguaia belts had sedimentation starting at around 1.1-1.0 Ga and final closure at 0.6 Ga. In the northern part of the Brasilia Belt occur the Barro Alto, Canabrava and Niquelandia maficultramafic layered complexes. Inconclusive U-Pb isotopic data indicate ages between ca. 1600 and 2000 Ma for these intrusions that were affected by highgrade metamorphism ca. 740-790 Ma ago, during the Neoproterozoic (Ferreira Filho et al. 1994; Suita et al. 1994; Correia et al. 1997). In the southern part of the Brasilia Belt, in central Goias , is the Anapolis-Itaucu granulite complex. It consists of a large complex of high-grade rocks, volcano-sedimentary sequences and granites, exposed in between metasediments of the Araxa Group, the main constituent of the internal zone of the Neoproterozoic Brasilia Belt (Fuck et al. 1994). These granulites have traditionally been interpreted as the exposure of Archean sialic basement to the sediments of the Brasilia Belt (Danni et al. 1982, Marini et al. 1984; Lacerda Filho and Oliveira 1995). This work reports the results of a regional Sm- Nd isotopic investigation and U-Pb SHRIMP data in order to assess (i) the nature of the protoliths of the Araxa Group in this area; (ii) the nature and the high grade metamorphism of rocks from Anapolis-Itaucu Complex; (iii) the crystallization and metamorphism of aluminous granites (au)

  3. Fine Belt-Buckles of Walrus Ivory – also Made in Greenland

    DEFF Research Database (Denmark)

    Roesdahl, Else

    On the production of decorative artefacts in Norse Greenland - and new finds of walrus ivory belt buckles......On the production of decorative artefacts in Norse Greenland - and new finds of walrus ivory belt buckles...

  4. Influence of aerosol-radiative forcings on the diurnal and seasonal cycles of rainfall over West Africa and Eastern Atlantic Ocean using GCM simulations

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyu-Myong [University of Maryland Baltimore County, Baltimore, MD (United States); Lau, William K.M.; Sud, Yogesh C. [Laboratory for Atmospheres, NASA/GSFC, Greenbelt, MD (United States); Walker, Gregory K. [SAIC/General Sciences Operation, Beltsville, MD (United States)

    2010-07-15

    Effects of aerosol radiative forcing on the diurnal and seasonal cycles of precipitation over West Africa and eastern Atlantic Ocean are investigated for the boreal summer season: June-July-August. An eight year (2000-2007) average of GCM simulated rainfall data is compared with the corresponding TRMM rainfall data. The comparison shows that the amplitude of the diurnal cycles of rainfall over land and ocean are reasonably well simulated. Over land, the phase of the simulated diurnal cycle of precipitation peaks several hours earlier than that of the TRMM data. Corresponding differences over the ocean(s) are relatively smaller. Some of the key features of the aerosol induced model simulated field anomalies are: (a) aerosol direct radiative forcing which increases the atmospheric stability and reduces the daytime moist convection and convective precipitation; (b) the aerosol induced changes in the diurnal cycle of precipitation are out of phase with those of the TRMM data over land, but are in-phase over the ocean; (c) aerosols reduce the amplitude of the diurnal cycle of precipitation over land and enhance it over ocean. However, the phase of the diurnal cycle is not affected much by the aerosol radiative forcing both over land and ocean. During the boreal summer, aerosol radiative forcing and induced circulation and precipitation cool the Sahel and the southern part of Sahara desert more than the adjacent areas to the north and south, thereby shifting the peak meridional temperature gradient northward. Consequently, an anomalous easterly jet is found north of its climatological location. This anomalous jet is associated with increased cyclonic circulation to the south of its axis, resulting in an anomalous monsoon rain belt in the Sahel. (orig.)

  5. Ages and origins of rocks of the Killingworth dome, south-central Connecticut: Implications for the tectonic evolution of southern New England

    Science.gov (United States)

    Aleinikoff, J.N.; Wintsch, R.P.; Tollo, R.P.; Unruh, D.M.; Fanning, C.M.; Schmitz, M.D.

    2007-01-01

    The Killingworth dome of south-central Connecticut occurs at the southern end of the Bronson Hill belt. It is composed of tonalitic and trondhjemitic orthogneisses (Killingworth complex) and bimodal metavolcanic rocks (Middletown complex) that display calc-alkaline affinities. Orthogneisses of the Killingworth complex (Boulder Lake gneiss, 456 ?? 6 Ma; Pond Meadow gneiss, ???460 Ma) were emplaced at about the same time as eruption and deposition of volcanic-sedimentary rocks of the Middletown complex (Middletown Formation, 449 ?? 4 Ma; Higganum gneiss, 459 ?? 4 Ma). Hidden Lake gneiss (339 ?? 3 Ma) occurs as a pluton in the core of the Killingworth dome, and, on the basis of geochemical and isotopic data, is included in the Killingworth complex. Pb and Nd isotopic data suggest that the Pond Meadow, Boulder Lake, and Hidden Lake gneisses (Killingworth complex) resulted from mixing of Neoproterozoic Gander terrane sources (high 207Pb/204Pb and intermediate ??Nd) and less radiogenic (low 207Pb/204Pb and low ??Nd) components, whereas Middletown Formation and Higganum gneiss (Middletown complex) were derived from mixtures of Gander basement and primitive (low 207Pb/204Pb and high ??Nd) sources. The less radiogenic component for the Killingworth complex is similar in isotopic composition to material from Laurentian (Grenville) crust. However, because published paleomagnetic and paleontologic data indicate that the Gander terrane is peri-Gondwanan in origin, the isotopic signature of Killingworth complex rocks probably was derived from Gander basement that contained detritus from non-Laurentian sources such as Amazonia, Baltica, or Oaxaquia. We suggest that the Killingworth complex formed above an east-dipping subduction zone on the west margin of the Gander terrane, whereas the Middletown complex formed to the east in a back-arc rift environment. Subsequent shortening, associated with the assembly of Pangea in the Carboniferous, resulted in Gander cover terranes over the

  6. Folding style controlled by intermediate decollement thickness change in the Lurestan region (NW of the Zagros fold-and-thrust belt), using analogue models

    Science.gov (United States)

    Farzipour Saein, Ali

    2016-07-01

    The basal and intermediate decollements play an important role in structural style of fold-and-thrust belts. The decollement units, or different mechanical stratigraphy within the rock units, are not uniform throughout the ZFTB and show a strong spatial variation. The Lurestan region with varied thickness of the intermediate decollement in its northern and southern parts is one of the most important parts of the Zagros fold-and-thrust belt, regarding its hydrocarbon exploration-extraction projects. Thickness variation of the intermediate decollement in different parts of the Lurestan region allows us to address its role on folding style. Based on scaled analogue modeling, this study outlines the impact of thickness and facies variation of sedimentary rocks in the northern and southern parts of this region on folding style. Two models simulated the mechanical stratigraphy and its consequent different folding styles of the northern and southern parts of the region. In the models, only thickness of the intermediate decollement (thick and thin) for the northern and southern parts of the Lurestan region was varied. Detached minor folds above the intermediate decollement were created in response to the presence of the thicker intermediate decollement, northern part of the study area, which consequently deformed complexly and disharmonically folded, in contrast to polyharmonic folding style in the section, compared to polyharmonic folding style in the southern part, where thin intermediate decollement exists. The model results documented that thickness variation of intermediate decollement levels could explain complex and different folding styles in natural examples which must be taken into account for hydrocarbon exploration throughout these areas.

  7. Tectonomorphic evolution of the Eastern Cordillera fold-thrust belt, Colombia: New insights based on apatite and zircon (U-Th)/He thermochronometers

    Science.gov (United States)

    Ghorbal, B.; Stockli, D. F.; Mora, A.; Horton, B. K.; Blanco, V.; Sanchez, N.

    2010-12-01

    The Eastern Cordillera (EC) of Colombia marks the eastern boundary of Cenozoic fold-thrust deformation in the northern Andes. It is a classic example of an inversion belt formed in the retro-arc region, in this case superimposed on a Triassic/Jurassic to Cretaceous intracontinental rift system of northern South America. Ongoing thrust reactivation (inversion) in this contractional orogen provides an excellent opportunity to study the patterns of deformation and influence of preexisting anisotropies (Mora et al., 2006). The objective of this detailed (U-Th)/He study is to unravel the tectonic and thermal evolution of the EC from the Magdalena Valley basin in the west to the Llanos foreland basin in the east and reconstruct the temporal and spatial progression of deformation in the EC fold-thrust belt. Furthermore, the Subandean or foothills zone of Colombia is key for understanding the petroleum systems in the complex frontal zone of the inverted fold-thrust belt. We present detailed apatite and zircon (U-Th)/He thermochronometric data from surface samples along a ~220 km WNW-ESE transect across the EC from the frontal fold-thrust belt at the edge of the Llanos basin to the western edge of the EC, the Magdalena basin. Surface and borehole zircon and apatite (U-Th)/He data, integrated with structural data, show that the EC fold-thrust belt propagated foreland-ward from the axial zone to the modern edges of the fold-thrust belt from at least the early Oligocene to the early Miocene. Detailed apatite and zircon (U-Th)/He data from surface samples and borehole samples in the foothills-Llanos transition zone and the Middle Magdalena Valley basin, between the large-displacement Guaicaramo and Pajarito-Chámeza thrusts in the east and the La Salina fault system in the west show a temporally complex evolution. The frontal fold-thrust belt was characterized by continued progressive foreland-ward migration of deformation and an apparent phase of major out-of-sequence motion

  8. The Guitiriz granite, Variscan belt of northern Spain: extension-controlled emplacement of magma during tectonic escape

    Science.gov (United States)

    Aranguren, Aitor; Tubia, JoséMaría; Bouchez, Jean Luc; Vigneresse, Jean Louis

    1996-03-01

    The Ollo de Sapo domain of the northern part of the Variscan belt of Spain, contains Precambrian and Ordovician metamorphic rocks intruded by the Guitiriz granite. The domain is bounded by two NS transcurrent shear zones. Detailed structural and anisotropy of magnetic susceptibility studies of the Guitiriz pluton reveal a syntectonic emplacement, relative to movement on the two NS trending bounding shear zones, characterized by: (1) development of NS trending structural and magnetic fabrics: (2) concordant structures in granites and country rocks; and (3) development of shear zones along the east and west granite margins. Gravity data show two roots trending 110°E extending down to 4.5 km from an otherwise thin (Sapo Domain — bounded by two shear zones acting as conjugate strike-slip zones.

  9. Post-Variscan evolution of the Anti-Atlas belt of Morocco constrained from low-temperature geochronology

    Science.gov (United States)

    Gouiza, M.; Charton, R.; Bertotti, G.; Andriessen, P.; Storms, J. E. A.

    2016-04-01

    The Anti-Atlas belt of Morocco extends ENE-WSW, over more than 600 km, from the Atlantic margin in the west to the interior of the African plate in the east. It exhibits Precambrian rocks outcropping as basement inliers and surrounded by marine Ediacaran-Cambrian sequences around the axis of the mountain range. The belt, which has for a long time been interpreted as of Variscan age, is now revealed to have experienced major vertical movements through Mesozoic and Cenozoic times. Thereby, the Anti-Atlas domain appears to be affected by two episodes of exhumation separated by an episode of subsidence. The initial episode occurred in the Late Triassic and led to the exhumation of 7.5-10.5 km of crustal rocks by the end of the Middle Jurassic (ca. 160-150 Ma). The following phase resulted in 1-3 km of basement subsidence and occurred during the Late Jurassic and most of the Early Cretaceous. The basement rocks were then slowly brought to the surface after experiencing 2-3.5 km of exhumation throughout the Late Cretaceous and the Cenozoic. The timing of these episodes of exhumation and subsidence coincides with major tectonic and thermal events in relation with the evolution of the Atlantic and Tethys Oceans, indicating that the effects of their rifting and drifting extended beyond their presumed margins.

  10. Tectonic-Climate Interactions in Action Orogenic Belts: Quantification of Dynamic Topography with SRTM data

    Science.gov (United States)

    Burbank, Douglas W.; Oskin, Mike; Niemi, Nathan; Miller, Scott

    2005-01-01

    This project was undertaken to examine the approach to steady state in collisional mountain belts. Although the primary thrust of this grant was to look at larger collisional mountain belts, such as the Himalaya, the Tien Shan, and Southern Alps, we began by looking at smaller structures represented by growing and propagating folds. Like ranges that are evolving toward a topographic steady state, these folds undergo a series of morphologic changes as they are progressively uplifted and eroded. We wanted to document the nature of these changes and to try to discern some of the underlying controls on them. We initially focused on the Wheeler Ridge anticline in southern California. Subsequently, we progressed to looking at the topographic development and the effects of differential uplift and glaciation on the Kyrgyz Range in the northern Tien Shan. This range is unusual inasmuch as it is transformed along its length from a simple uplift with a largely preserved Mesozoic erosion surface arching across it to a highly dissected and heavily glaciated uplift in the region where uplift has been sustained at higher rates over longer intervals. In efforts to understand the distribution of erosion rates at 10(exp 3) - 10(exp 5) year time scales, cosmogenic radionuclide (CRN) concentrations have been gaining increasingly widespread usage (Brown et al., 1995; Riebe et al., 2004; Riebe et al., 2001; Vance et al., 2003). Most studies to date, however, have been conducted in slowly eroding ranges. In rapidly eroding mountains where landslides deliver most of the sediments to the rivers, we hypothesized that CRN concentrations could be highly perturbed by the stochastic processes of landsliding. Therefore, we undertook the development of a numerical model that simulated the effects of both landsliding and grain-by-grain attrition within fluvial catchments. This modeling effort has shown the effects of catchment size and erosion rate on CRN concentrations and allows a prediction of

  11. West Coast Fishing Closures, 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data delineate state and federally managed ocean areas off the West Coast of the United States that are closed to or have restrictions on commercial or...

  12. GeoPowering the West

    Energy Technology Data Exchange (ETDEWEB)

    2007-02-01

    Summary brochure of GeoPowering the West (GPW) activities, and areas of technology transfer and market transformation. It also provides current contact information for key DOE and national laboratory staff representing the GPW program.

  13. The exotic fresh-water snail Helisoma duryi (Wetherby, 1879) (Planorbidae) In Southern Africa

    NARCIS (Netherlands)

    Appleton, C.C.

    1977-01-01

    INTRODUCTION Van Bruggen (1974) discussed the identity of specimens of the North American pulmonate genus Helisoma Swainson, 1840 (Mollusca: Planorbidae) from three localities in southern Africa. He identified Helisoma (Seminolina) cf. duryi seminole Pilsbry, 1934, from a farm dam in South West Afri

  14. Doing Business 2014 Regional Profile : Common Market for Eastern and Southern Africa

    OpenAIRE

    World Bank; International Finance Corporation

    2013-01-01

    This regional profile presents the Doing Business indicators for economies in Common Market for Eastern and Southern Africa (COMESA). It also shows the regional average, the best performance globally for each indicator and data for the following comparator regions: Europe and Central Asia, Economic Community of West African States, Middle East and North Africa, Organization for the Harmoni...

  15. Effects of climate variability and climate change on crop production in southern Mali

    NARCIS (Netherlands)

    Traore, B.; Corbeels, M.; Wijk, van M.T.; Rufino, M.C.; Giller, K.E.

    2013-01-01

    In West Africa predictions of future changes in climate and especially rainfall are highly uncertain, and up to now no long-term analyses are available of the effects of climate on crop production. This study analyses long-term trends in climate variability at N'Tarla and Sikasso in southern Mali us

  16. WISE Albedos for Tens of Thousands of Main Belt Asteroids

    NARCIS (Netherlands)

    Masiero, Joseph R.; Mainzer, A. K.; Bauer, J.; Cutri, R.; Dailey, J.; Delbo, M.; Grav, T.; McMillan, R. S.; Mueller, M.; Walker, R.; Wright, E.; WISE Science Team, [No Value

    2010-01-01

    Using thermal IR data from the Wide-field Infrared Survey Explorer (WISE) mission we have calculated diameters for tens of thousands of previously known Main Belt asteroids. Using archival optical observations we have also determined albedos for each object. We present our results from this investig

  17. Resolving the Planetesimal Belt of HR 8799 with ALMA

    CERN Document Server

    Booth, Mark; Casassus, Simon; Hales, Antonio S; Dent, William R F; Faramaz, Virginie; Matrà, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge

    2016-01-01

    The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their orbits and a halo of small grains. With the infrared data, it is hard to distinguish the planetesimal belt emission from that of the grains in the halo. With this in mind, the system has been observed with ALMA in band 6 (1.34 mm) using a compact array format. These observations allow the inner edge of the planetesimal belt to be resolved for the first time. A radial distribution of dust grains is fitted to the data using an MCMC method. The disc is best fit by a broad ring between $145^{+12}_{-12}$ AU and $429^{+37}_{-32}$ AU at an inclination of $40^{+5}_{-6}${\\deg} and a position angle of $51^{+8}_{-8}${\\deg}. A disc edge at ~145 AU is too far out to be explained simply by interactions with planet b, requiring either a more complicated dynamical history or an extra planet beyond the orb...

  18. 1991 National campaign to increase safety belt usage.

    NARCIS (Netherlands)

    National Highway Traffic Safety Administration NHTSA

    1992-01-01

    The central theme of this paper is the national campaign of the USA to be conducted in 1991 and 1992, in order to reach the goal of 70 percent safety belt usage by 1992. Among other things, it is shown that visible enforcement of existing laws offers the greatest potential for achieving this goal. F

  19. Belt charging system for the 35 MV Vivitron accelerator

    International Nuclear Information System (INIS)

    A Van de Graaff belt charging system has been chosen for the Vivitron. Although classical in its principle and conservative in its design, it includes different new features that will be discussed in detail. The main electrical and mechanical characteristics are also reviewed together with the status of the project

  20. Radiation Belt Storm Probes (RBSP) Payload Safety Introduction Briefing

    Science.gov (United States)

    Loftin, Chuck; Lampert, Dianna; Herrburger, Eric; Smith, Clay; Hill, Stuart; VonMehlem, Judi

    2008-01-01

    Mission of the Geospace Radiation Belt Storm Probes (RBSP) is: Gain s cientific understanding (to the point of predictability) of how populations of relativistic electrons and ions in space form or change in response to changes in solar activity and the solar wind.

  1. Chaos in Mean Motion Resonances of the Kuiper Belt

    CERN Document Server

    Franklin, Fred

    2014-01-01

    In this paper on mean motion resonances in the Kuiper belt we consider effects on resonant bodies captured in an earlier migration by determining levels of chaos as a function of eccentricity, e, at the most stable orbital configuration. We find the the maximum observed e's at resonance very closely correspond to orbits with Lyapunov times ~ 1000 orbital periods of Neptune--much the same number as applies in the asteroid belt with Neptune's period replaced by Jupiter's. The fact that this number caps the e's of markedly chaotic but still existing bodies, implies that the great majority of escapes at equal and larger e's have already occurred. Yet escapes must continue at some level if the small population in the outermost belt is to be maintained because typical lifetimes of bodies there are only ~ 1/10 of the solar system's age. A study of stability at resonance also reinforces the claim that the post-migration boundary of the inner Kuiper belt lies near 34 AU and that the primordial, or pre-migration, outer...

  2. Development of a new Global RAdiation Belt model: GRAB

    Science.gov (United States)

    Sicard-Piet, Angelica; Lazaro, Didier; Maget, Vincent; Rolland, Guy; Ecoffet, Robert; Bourdarie, Sébastien; Boscher, Daniel; Standarovski, Denis

    2016-07-01

    The well known AP8 and AE8 NASA models are commonly used in the industry to specify the radiation belt environment. Unfortunately, there are some limitations in the use of these models, first due to the covered energy range, but also because in some regions of space, there are discrepancies between the predicted average values and the measurements. Therefore, our aim is to develop a radiation belt model, covering a large region of space and energy, from LEO altitudes to GEO and above, and from plasma to relativistic particles. The aim for the first version is to correct the AP8 and AE8 models where they are deficient or not defined. At geostationary, we developed ten years ago for electrons the IGE-2006 model which was proven to be more accurate than AE8, and used commonly in the industry, covering a broad energy range, from 1keV to 5MeV. From then, a proton model for geostationary orbit was also developed for material applications, followed by the OZONE model covering a narrower energy range but the whole outer electron belt, a SLOT model to asses average electron values for 2international partnership. This model will be called the GRAB model, as Global Radiation Belt model. We will present first beta version during this conference.

  3. Effective Conveyor Belt Inspection for Improved Mining Productivity

    Energy Technology Data Exchange (ETDEWEB)

    Chris Fromme

    2006-06-01

    This document details progress on the project entitled ''Effective Conveyor Belt Inspection for Improved Mining Productivity'' during the period from November 15, 2004 to May 14, 2004. Highlights include fabrication of low-cost prototype hardware, acquisition of infrared thermal data, and initial design of a Smart-Camera based system.

  4. Uranium deposits of the Grants, New Mexico mineral belt (II)

    International Nuclear Information System (INIS)

    This is part of a study of the genesis of the U deposits of the Grants mineral belt. Enrichment of Mg in ore zones is frequently observed, with chlorite being a common product. Clay mineralogic studies argue for chlorite-illite-montmorillonite associations with ores. The methods include scanning electron microscopy, Eh-pH diagrams, activation analysis, and rare earth element studies

  5. Design study of flat belt CVT for electric vehicles

    Science.gov (United States)

    Kumm, E. L.

    1980-01-01

    A continuously variable transmission (CVT) was studied, using a novel flat belt pulley arrangement which couples the high speed output shaft of an energy storage flywheel to the drive train of an electric vehicle. A specific CVT arrangement was recommended and its components were selected and sized, based on the design requirements of a 1700 KG vehicle. A design layout was prepared and engineering calculations made of component efficiencies and operating life. The transmission efficiency was calculated to be significantly over 90% with the expected vehicle operation. A design consistent with automotive practice for low future production costs was considered, together with maintainability. The technology advancements required to develop the flat belt CVT were identified and an estimate was made of how the size of the flat belt CVT scales to larger and smaller design output torques. The suitability of the flat belt CVT for alternate application to an electric vehicle powered by an electric motor without flywheel and to a hybrid electric vehicle powered by an electric motor with an internal combustion engine was studied.

  6. Resolving the planetesimal belt of HR 8799 with ALMA

    Science.gov (United States)

    Booth, Mark; Jordán, Andrés; Casassus, Simon; Hales, Antonio S.; Dent, William R. F.; Faramaz, Virginie; Matrà, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge

    2016-07-01

    The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their orbits and a halo of small grains. With the infrared data, it is hard to distinguish the planetesimal belt emission from that of the grains in the halo. With this in mind, the system has been observed with ALMA in band 6 (1.34 mm) using a compact array format. These observations allow the inner edge of the planetesimal belt to be resolved for the first time. A radial distribution of dust grains is fitted to the data using an MCMC method. The disc is best fitted by a broad ring between 145^{+12}_{-12} au and 429^{+37}_{-32} au at an inclination of 40^{+5}_{-6}° and a position angle of 51^{+8}_{-8}°. A disc edge at ˜145 au is too far out to be explained simply by interactions with planet b, requiring either a more complicated dynamical history or an extra planet beyond the orbit of planet b.

  7. Influence of the Gould Belt on Interstellar Extinction

    CERN Document Server

    Gontcharov, George

    2016-01-01

    A new analytical 3D model of interstellar extinction within 500 pc of the Sun as a function of the Galactic spherical coordinates is suggested. This model is physically more justified than the widely used Arenou model, since it takes into account the presence of absorbing matter both in the layer along the equatorial Galactic plane and in the Gould Belt. The extinction in the equatorial layer varies as the sine of the Galactic longitude and in the Gould Belt as the sine of twice the longitude in the Belt plane. The extinction across the layers varies according to a barometric law. It has been found that the absorbing layers intersect at an angle of 17 deg and that the Sun is located near the axial plane of the absorbing layer of the Gould Belt and is probably several parsecs below the axial plane of the equatorial absorbing layer but above the Galactic plane. The model has been tested using the extinction of real stars from three catalogs.

  8. Incipient Crustal Stretching across AN Active Collision Belt: the Case of the Siculo-Calabrian Rift Zone (central Mediterranean)

    Science.gov (United States)

    Catalano, S.; Tortorici, G.; Romagnoli, G.; Pavano, F.

    2012-12-01

    In the Central Mediterranean, the differential roll-back of the subducting Nubia Plate caused the Neogene-Quaternary extrusion of the Calabrian arc onto the oceanic Ionian slab, and the opening of the oceanic Tyrrhenian Basin, in the overriding Eurasia Plate. The differential motion at the edges of the arc was largely accommodated along transform faults that propagated across the orogenic belt. Since the Late Quaternary, the southern edge of the arc has been replaced by the roughly N-S oriented Siculo-Calabrian Rift Zone (SCRZ) that formed as the NNW-directed normal faults of NE Sicily, crossing the orogenic belt, have linked the NNE-oriented Tyrrhenian margin of southern Calabria with the NNW-trending Africa-Ionian boundary of southeastern Sicily. Our study focused on the Sicily shoulder of the SCRZ, where the transition zone between the extensional belt and the still active Nubia-Eurasia convergent margin is characterized by two distinct mobile crustal wedges, both lying on an upwarped Mantle, where a re-orientations of the σ1 is combined with volcanism (e.g. Etna, Aeolian islands) and a huge tectonic uplift. In southeastern Sicily, the Hyblean-Etnean region evolved, since about 0.85 Ma, as an indipendent crustal wedge, moving towards the NNW and pointing to the active Mt. Etna volcano. A local ENE crustal stretching accompanied the traslation of the block and pre-dated the ESE-oriented extension governing the propagation of the southernmost branch of the SCR, which started at about 330 ka B.P.. Similarly, the Peloritani-Aeolian region, flanked by the 125 ka-old NE-Sicily branch of the rift zone, represents a mostly submerged crustal wedge that migrates towards the NE, diverging from the rest of the Sicily collision zone and pointing to the Stromboli volcano. The Peloritani-Aeolian block is characterized by the occurrence of a wide central NE-oriented collapsed basin contoured by an actively uplifting region, whose tectonic boundaries are evidenced by a sharp

  9. Great Carbonate Bank of Yucatan, Southern Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Viniegra-O, F.

    1981-01-01

    Since 1972, numerous large and giant oil fields have been discovered in the Reforma area of Chiapas and Tabasco States, southern Mexico, and on the offshore Campeche shelf west of Campeche State. The huge carbonate bank with which these discoveries are associated is called the Great Carbonate Bank of Yucatan. Present trap structures are mainly fractured and faulted domal salt pillows created during the Laramide orogeny. The Great Carbonate Bank of Yucatan is believed to include not just the Yucatan Peninsula, but also a part of coastal Veracruz State, where several discoveries have been made in carbonate rocks of Early to Middle Cretaceous ages in thrust sheets along the western margin of the Veracruz basin, which are now buried beneath the coastal plain. It is probable that large, subthrust, anticlinal structures underlie the thrust sheets along the western margin of the Veracruz basin, and these when drilled, may contain important hydrocarbon accumulations. (JMT)

  10. Global Storm-Time Depletion of the Outer Electron Belt

    Science.gov (United States)

    Ukhorskiy, A. Y.; Sitnov, M. I.; Millan, R. M.; Kress, B. T.; Fennell, J. F.

    2014-12-01

    The outer radiation belt consists of relativistic (≳0.5 MeV) electrons trapped on closed trajectories around Earth where its magnetic field is nearly dipolar. During increased geomagnetic activity electron intensities in the belt can vary by orders of magnitude at different spatial and temporal scale. The main phase of geomagnetic storms often produces deep depletions of electron intensities over broad regions of the outer belt. Previous studies identified three possible processes that can contribute to the depletions: fully adiabatic inflation of electron drift orbits caused the ring current growth, electron loss into the atmosphere due to pitch-angle scattering by plasma waves (e.g., EMIC and whistler waves), and electron escape through the magnetopause boundary. In this paper we investigate the relative importance of the magnetopause losses to the rapid depletion of the outer belt observed at the Van Allen Probes spacecraft during the main phase of March 17, 2013 storm. The intensities of > 1 MeV electrons were depleted by more that an order of magnitude over the entire radial extent of the belt in less than 6 hours after the sudden storm commencement. For the analysis we used three-dimensional test-particle simulations of global evolution of the outer belt in the Tsyganenko-Sitnov (TS07D) magnetic field model with the inductive electric field. The comparison of the simulation results with electron measurements from the MagEIS experiment shows that the magnetopause losses in the model accounts for most of the observed depletion. The individual electron motion the process is non-adiabatic; the third invariant is violated by global variations of the inner magnetospheric fields caused by the magnetopause compressions and the buildup of ring current, while the second invariant is violated at drift orbit bifurcations. The analysis shows that the observed deep depletion of radiation belt intensities is enabled by the change in the global configuration of magnetic

  11. Mental Status after West Nile Virus Infection

    OpenAIRE

    Haaland, Kathleen Y.; Sadek, Joseph; Pergam, Steven; Echevarria, Leonor A.; Davis, Larry E.; Goade, Diane; Harnar, Joanne; Nofchissey, Robert A.; Sewel, C. Mack; Ettestad, Paul

    2006-01-01

    Mental status after acute West Nile virus infection has not been examined objectively. We compared Telephone Interview for Cognitive Status scores of 116 patients with West Nile fever or West Nile neuroinvasive disease. Mental status was poorer and cognitive complaints more frequent with West Nile neuroinvasive disease (p = 0.005).

  12. Structural and metamorphic evidence for the mechanism of exhumation of the schist belt, south-central Brooks Range, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Dinklage, W.S.; Patrick, B.E. (Univ. of California, Santa Barbara, CA (United States). Dept. of Geologic Sciences)

    1992-01-01

    The mid to late mesozoic Brookian orogeny involved southward subduction underneath an island arc and subsequent burial of a passive continental margin. Field mapping, petrography, and geochronology of blueschist-bearing metasedimentary rocks in the Walker Lake region of the southern Brooks Range enables correlation of fabrics with crustal movements that are responsible for their burial and exhumation. Observed early ductile fabrics in the schist belt are consistent with north-vergent transport. These fabrics include (1) S[sub D] (dominant foliation), a south-dipping transposed crenulation cleavage which formed under blueschist facies conditions; (2) outcrop-scale north-vergent folds and an associated mesoscopic south-dipping crenulation cleavage, S[sub D+1]; (3) kilometer-scale gentle warps and north-vergent, open monoclinal folds. Small north-vergent folds (fabric 2) fold an earlier mineral stretching lineation associated with S[sub D]. The similarity of orientation of the three fabrics and their evolution in time from small and isoclinal to large and open suggests that they are the product of progressive deformation. S[sub D] is likely a burial fabric; later fabrics may be related to uplift along a regionally penetrative system of ductile, north-vergent south-dipping thrusts. A metamorphic overprint, dated at 105--110 Ma, increases to amphibolite facies toward the north and outlasts north-vergent fabrics. Retrograde helicitic albite is commonly rotated by later minor extensional crenulation cleavages. Discrete, narrow zones of ductile deformation in the southernmost schist belt, parallel to S[sub D] but postdating blueschist facies conditions, locally exhibit top-to-the-south sense of shear. This evidence suggest that north-vergent contraction continued during exhumation of the schist belt from deep to mid-crustal levels and that extension may have been responsible for exhumation from middle to shallow crustal levels.

  13. Evidences of inclined transpression at the contact between Vinjamuru group and Udayagiri group of Nellore Schist Belt, Andhra Pradesh, India

    Indian Academy of Sciences (India)

    Sankha Das; Devasheesh Shukla; S K Mitra

    2016-07-01

    The Nellore Schist Belt (NSB) is a curvilinear Archaean schist belt, approximately 350 km long and 8–50 km wide. The Nellore Schist Belt is considered to be Neoarchean in age and stratigraphically NSB is classified as the western Udayagiri group (dominated by metasediments) and underlying eastern Vinjamuru group (dominated by metabasalts). There is a long controversy regarding the contact relationship between Udayagiri and Vinjamuru groups. Earlier researchers regarded the contact between two groups as tectonic on the basis of metamorphism. A shear zone and a possible thrust contact between the two groups have also been reported. On the basis of present study, an NNW–SSE trending, westerly dipping inclined transpressional zone is found at the contact between Udayagiri and Vinjamuru groups in the central western part of the NSB. Kinematic analysis of both the hanging wall and foot wall of the westerly dipping thrust zone shows presence of strong S1 schistosity, shear bands and S-C fabric in both strike and dip section along with east-verging overturned fold, westerly dipping inverted beds, suggesting partitioning of non-coaxial deformation in strike-slip and dip-slip component along with a pure shear component. Strike-slip is more prominent in the northern part of the contact than the southern part. The presence of steep to moderate northerly plunging non-orthogonal stretching/mineral elongation lineation all along the contact and clockwise shift of plot of the same in stereo net from its orthogonal position and presence of other kinematic indicators in plan suggests a right lateral strike-slip component. As a whole, it is suggested that Udayagiri group is thrusted over Vinjamuru group along a westerly dipping thrust plane with a right lateral strike-slip motion and simultaneous E–W contraction.

  14. Use of the Cropland Data Layer to monitor grassland conversion in the U.S. Western Corn Belt (Invited)

    Science.gov (United States)

    Wright, C.; Wimberly, M. C.

    2013-12-01

    The U.S. Department of Agriculture's Cropland Data Layer (CDL) provides new opportunities for monitoring land cover/land use change (LCLUC) related to U.S. agricultural policy, bioenergy development, and recent commodity price increases. We used the CDL to assess the conversion of grasslands to corn/soy cultivation along the western periphery of the U.S. Corn Belt. Here, we find rapid grassland conversion (1-5% annually) as the Corn Belt expands westward and northward into North Dakota and South Dakota. This LCLUC is occurring in close proximity to wetlands in the Prairie Pothole Region. In most counties in the eastern Dakotas, grassland conversion exceeds declines in land area enrolled in the Conservation Reserve Program (CRP). Within the core corn/soy growing area in Iowa and southern Minnesota, LCLUC is occurring on marginal lands characterized by high erosion potential and less-productive soils. In Minnesota, particularly, corn/soy production is increasing on lands previously too wet to farm without an expansion of agricultural drainage practices. Over the period 2006-2011, we estimate a net greenhouse gas impact of grassland conversion in the Western Corn Belt of approximately 4*106 metric tons CO2-equivalent. Although not designed for monitoring grasslands, we suggest that the CDL can be used judiciously to identify grassland conversion at farm- to sub-county scales, and, in conjunction with other national-level datasets (e.g., the National Wetlands Inventory and SSURGO database), to provide timely feedback to policymakers and the public on likely environmental impacts of U.S. agricultural policies and shifting market forces.

  15. Flexible electrode belt for EIT using nanofiber web dry electrodes

    International Nuclear Information System (INIS)

    Efficient connection of multiple electrodes to the body for impedance measurement and voltage monitoring applications is of critical importance to measurement quality and practicality. Electrical impedance tomography (EIT) experiments have generally required a cumbersome procedure to attach the multiple electrodes needed in EIT. Once placed, these electrodes must then maintain good contact with the skin during measurements that may last several hours. There is usually also the need to manage the wires that run between the electrodes and the EIT system. These problems become more severe as the number of electrodes increases, and may limit the practicality and portability of this imaging method. There have been several trials describing human–electrode interfaces using configurations such as electrode belts, helmets or rings. In this paper, we describe an electrode belt we developed for long-term EIT monitoring of human lung ventilation. The belt included 16 embossed electrodes that were designed to make good contact with the skin. The electrodes were fabricated using an Ag-plated PVDF nanofiber web and metallic threads. A large contact area and padding were used behind each electrode to improve subject comfort and reduce contact impedances. The electrodes were incorporated, equally spaced, into an elasticated fabric belt. We tested the electrode belt in conjunction with the KHU Mark1 multi-frequency EIT system, and demonstrate time-difference images of phantoms and human subjects during normal breathing and running. We found that the Ag-plated PVDF nanofiber web electrodes were suitable for long-term measurement because of their flexibility and durability. Moreover, the contact impedance and stability of the Ag-plated PVDF nanofiber web electrodes were found to be comparable to similarly tested Ag/AgCl electrodes. (paper)

  16. Solar Modulation of Inner Trapped Belt Radiation Dose Rate

    Science.gov (United States)

    Diaz, Abel

    2002-03-01

    The two steady sources of radiation in low Earth orbit are the inner trapped-belt and galactic cosmic radiation (GCR), which present a very significant hazard to the astronauts and flight equipment electronics. The fluxes of GCR and inner trapped-belt particles at a fixed altitude are modulated by solar activity. They decrease with increasing solar activity in general. The mechanism of these two sources of radiation are, however, very different. In this project we shall be concerned with modeling the inner trapped-belt protons. The existing trapped-belt models, namely AP-8 is based on data acquired prior to 1970 during solar cycle 20 with relatively low solar flux. These models describe the environment at solar minimum and solar maximum only. Cycles 21 and 22 were much larger, but no valid radiation model exists for such large values. Moreover, the existing models like AP-8, CRRESPRO, and GOST describe the flux to an accuracy of a factor of two to five. There is clear need to accurately predict radiation exposure of astronauts and equipment at all times between the solar minimum and solar maximum, not only on the short duration Space Shuttle flights, but also the longer term stay onboard the International Space Station. In our approach we are taking into account some important parameters, which are responsible for energy losses of protons within the belts. These energy losses are primarily to electrons and by collisions to atmospheric nuclei. Accordingly the atmospheric density dependence at a certain altitude during a specific solar activity is an important parameter that needs to be accurately incorporated into a realistic model. We are involved in developing such a model, which would enable us to predict the radiation exposure for all occasions.

  17. Uranium mineralization environment and prospecting potential of Dawan ore field in Nanling metallogenic belt

    International Nuclear Information System (INIS)

    Located in the middle part of Jiuyishan complex pluton, Nanling metallogenic belt, Dawan uranium ore field in Hunan Province is an important uranium-producing and rare metal, nonferrous metal cluster area due to the favourable mineralization environment. The Cambrian is the main uranium source bed and their contact zone to the pluton is the favorable part for mineralization. The uranium deposits which have been explored are all located in the exocontact zone of Jinjiling pluton in the middle part of Jiuyishan complex pluton which is composed of the independent eastern and western magma evolution centers. In the west center, Jinjiling pluton is closely related to uranium mineralization where the trinity geologic setting was formed with magma evolution, hydrothermal fluid action and mineralization. The deep slitted and large faults provide the pathway and thermodynamic source for circulating migration of mineralizing fluid. The uranium mineralization mainly occurred in crustal stress conversion period of Late Cretaceous and related to the tensive NW extending fault and deep originated fluid. The gravity, aero magnetic, airborne gamma-ray spectrometry anomalies and radioactivity hydrochemical anomaly are important criteria for uranium prospecting. Based on the analysis of regional uranium mineralization environment, the prospecting potential is forecasted. (authors)

  18. The JCMT Legacy Survey of the Gould Belt: a first look at Taurus with HARP

    CERN Document Server

    Davis, C J; Hatchell, J; Wouterloot, J G A; Buckle, J V; Nutter, D; Fich, M; Brunt, C; Butner, H; Cavanagh, B; Curtis, E I; Duarte-Cabral, A; Di Francesco, J; Etxaluze, M; Friberg, P; Friesen, R; Fuller, G A; Graves, S; Greaves, J S; Hogerheijde, M R; Johnstone, D; Matthews, B; Matthews, H; Rawlings, J M C; Richer, J S; Roberts, J; Sadavoy, S; Simpson, R J; Tothill, N; Tsamis, Y; Viti, S; Ward-Thompson, D; White, Glenn J; Yates, J

    2010-01-01

    As part of a JCMT Legacy Survey of star formation in the Gould Belt, we present early science results for Taurus. CO J=3-2 maps have been secured along the north-west ridge and bowl, collectively known as L 1495, along with deep 13CO and C18O J=3-2 maps in two sub-regions. With these data we search for molecular outflows, and use the distribution of flows, HH objects and shocked H2 line emission features, together with the population of young stars, protostellar cores and starless condensations to map star formation across this extensive region. In total 21 outflows are identified. It is clear that the bowl is more evolved than the ridge, harbouring a greater population of T Tauri stars and a more diffuse, more turbulent ambient medium. By comparison, the ridge contains a much younger, less widely distributed population of protostars which, in turn, is associated with a greater number of molecular outflows. We estimate the ratio of the numbers of prestellar to protostellar cores in L 1495 to be ~ 1.3-2.3, and...

  19. ESTIMATION OF EXPECTED MAXIMUM WATER LEVEL DUE TO TIDE AND TSUNAMI INTERACTION ALONG THE COASTAL BELTS OF PENANG ISLAND IN PENINSULAR MALAYSIA

    Directory of Open Access Journals (Sweden)

    Ahmad Izani Md. Ismail

    2010-01-01

    Full Text Available In this paper, an estimate of the expected maximum water levels associated with tide and tsunami interaction is computed along the coastal belts of Penang Island in Peninsular Malaysia. For this purpose, a nonlinear Polar coordinate shallow water model of the Indonesian tsunami of 2004 by Roy et al. (2007b is used. Appropriate tidal condition is generated in the domain by applying tidal forcing through the western open sea boundary. For studying tide and tsunami interaction, the 2004 Indonesian tsunami is introduced in the previously generated tidal oscillation. The expected maximum possible water level along the coastal belts of Penang Island is estimated based on the interaction of tide and tsunami for different tidal conditions (high and low tidal periods. It is seen that the surge level is very sensitive towards the coastal belts due to interaction during high tide. The west coast of Penang Island is found to be vulnerable for stronger surge due to interaction. The influence of tidal wave on the tsunami wave height towards Penang Island is also investigated. The tide was found to have a significant effect in tsunami enhancement in the coastal regions.

  20. ASSESSMENT OF HOMEOWNERSHIP AND ASSET POVERTY IN THE ALABAMA BLACK BELT AND NON-BLACK BELT COUNTIES

    OpenAIRE

    Kanyi, Peter M.; Baharanyi, Ntam; Ngandu, Mudiayi Sylvain; Zabawa, Robert

    2008-01-01

    This study assessed homeownership and how it is affected by race, residency in or out of Alabama Black Belt, family status, poverty and other variables. All variables showed significant relationship to Alabama homeownership with single-parenthood showing a negative impact on White homeownership but insignificant to Black homeownership in the region.