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Sample records for mountain-lemei rock area

  1. Heat flow studies in the Steamboat Mountain-Lemei Rock area, Skamania County, Washington. Information circular 62

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, J.E.; Blackwell, D.D.; Hammond, P.E.; Huntting, M.T.

    1978-01-01

    In order to investigate the possible occurrence of geothermal energy in areas of Quaternary basaltic volcanism, the Washington State Department of Natural Resources drilled several 152 m deep heat-flow holes in the Steamboat Mountain-Lemei Rock area of Skamania County, Washington. The study area is located in the southern part of Washington's Cascade Mountains between 45/sup 0/54' and 46/sup 0/07' N. and 121/sup 0/40' and 121/sup 0/53'W. This area was selected for study because geologic mapping had identified a north-trending chain of late Quaternary basaltic volcanoes that had extruded a sequence of lava flows up to 600 m thick and because the chain of volcanoes is areally coincident with a well-defined gravity low with a minimum value of about -110 mgals. Gradients of 52.7 and 53.4/sup 0/C/km and heat flows of 1.8 and 1.6 ..mu..cal/cm/sup 2/sec, respectively, were measured in two drill holes near the east flank of the chain of volcanoes. Gradients of 44.5 and 58/sup 0/C/km and heat flows of 1.3 and 1.6 ..mu..cal/cm/sup 2/ sec, respectively, were measured in two holes near the axis of the chain, and one gradient of 49.8/sup 0/C/km and heat flow of 1.5 ..mu..cal/cm/sup 2/ sec were measured in a drill hole near the west flank of the chain. All gradients and heat flows are terrain corrected. These heat-flow values are typical regional heat-flow values for the Cascade Mountains. The data show that there is no large-sized heat source body within the general area of the heat-flow study. However, there is only one location in Washington, also in the Cascade Mountains, where higher gradients have been measured.

  2. Triassic carbonate rocks in the Phatthalung area, Peninsular Thailand

    Science.gov (United States)

    Ampornmaha, Apsorn

    Carbonate rocks in the Phatthalung area and others in Peninsular Thailand have been known as the Permian Rat Buri Limestone. The study area is characterized by several isolated limestone mountains and is located in Phatthalung province. Micropaleontological study of these carbonate rocks indicates that they should be assigned a late Early to Late Triassic age. The Chaiburi Formation is newly proposed and divided into three members: the Phukhaothong Dolomite, Chiak Limestone and Phanomwang Limestone in ascending order. The Phukhaothong Dolomite consists of thickly bedded to massive dolomite and yields Neospathodus kummeli Sweet, N. waageni Sweet, N. cfr. waageni Sweet and other conodonts that indicate Dienerian to Smithian (Early Triassic). The Chiak Limestone Member consists of bedded and laminated limestone with intercalated thin chert layers and nodules. This limestone commonly yields Early Triassic to Middle Triassic conodonts such as Neospathodus timorensis (Nogami) and Neospathodus kockeli (Tatge), both reliable indicators of latest Spathian to early Anisian, and rare occurrences of Neogondolella bulgarica (Budurov and Stefanov), an indicator of the middle Anisian. The Phanomwang Limestone Member is mostly massive limestone with intercalated reef limestone (coral buildups) and yields abundant fossils that indicate Carnian (Late Triassic). Microfacies analysis and stratigraphic sequences of carbonate rocks in this area show the gradual change of depositional environment from low to high energy conditions.

  3. Hot Dry Rock resources of the Clear Lake area, California

    Energy Technology Data Exchange (ETDEWEB)

    Burns, K.L.; Potter, R.M. [Los Alamos National Lab., NM (United States); Peake, R.A. [California Energy Commission, CA (United States)

    1995-01-01

    The Hot Dry Rock resources of the Clear Lake area of northern California are hot, large and areally uniform. The geological situation is special, probably overlying a slabless window caused by interaction between tectonic plates. Consequent magmatic processes have created a high-grade resource, in which the 300{degree}C isotherm is continuous, subhorizontal, and available at the shallow depth of 2.4 to 4.7 km over an area of 800 km{sup 2}. The region is very favorable for HDR development.

  4. Hydrocarbon- Generating Model of the Area Covered With Volcanic Rock

    Institute of Scientific and Technical Information of China (English)

    Guo Zhanqian; Zhang Yuwei

    2000-01-01

    The distribution of Oil & gas fields shows their close relationship with the most active tectonic regions. This is not a coincidence but having a scientific reasons. The crustal active regions, refer to the places where the active natural earthquake, volcanic activities, underground water happened, and the areas of the leaking off of natural gas to the surface of the crust. The magma of volcanic activities brings the organic "kitchen range body" hydrocarbon- generating model and inorganic genetic hydrocarbon to the regions covered by volcanic rock. Underground water brings a catalytic hydrocarbongenerating model for organic matter, and the leaking- off of H2 and CO2 contributes a synthetic hydrocarbon - generating model. Volcanic activities bring the assemblage of Source, Reservoir and Seal formed by the sediments and magma the sedimentary basins, and the hydrocarbon - generating system with a "water - volcano" binary structure is formed. All these conditions are favorable and excellent for the formation of oil & gas fields. The distribution of American oil & gas fields have very close relationship with the mines of Fe, Mn, Ct, Mo, W and V, deposits of Zn, Cu, V, Pb, Al and Hg, and the deposits of fluorite, sulfur, potassium salt, phosphate and halite, and the distribution of sulfate- chloride of river water. The reason why few oil & gas fields discovered in the regions covered by volcanic rock in western America maybe because of the view of "inconsistency between petroleum and volcano". Further more, It's very difficult to carry out a geophysical exploration in such kinds of regions.This paper examined a few hydrocarbon-generating models (systems) mentioned above and came up with some fresh ideas on the exploration in the areas covered with volcanic rocks.

  5. Assessment of industrial minerals and rocks in the controlled area

    Energy Technology Data Exchange (ETDEWEB)

    Castor, S.B. [Nevada Bureau of Mines and Geology, Reno, NV (United States); Lock, D.E. [Mackay School of Mines, Reno, NV (United States)

    1996-08-01

    Yucca Mountain in Nye County, Nevada, is a potential site for a permanent repository for high-level nuclear waste in Miocene ash flow tuff. The Yucca Mountain controlled area occupies approximately 98 km{sup 2} that includes the potential repository site. The Yucca Mountain controlled area is located within the southwestern Nevada volcanic field, a large area of Miocene volcanism that includes at least four major calderas or cauldrons. It is sited on a remnant of a Neogene volcanic plateau that was centered around the Timber Mountain caldera complex. The Yucca Mountain region contains many occurrences of valuable or potentially valuable industrial minerals, including deposits with past or current production of construction aggregate, borate minerals, clay, building stone, fluorspar, silicate, and zeolites. The existence of these deposits in the region and the occurrence of certain mineral materials at Yucca Mountain, indicate that the controlled area may have potential for industrial mineral and rock deposits. Consideration of the industrial mineral potential within the Yucca Mountain controlled area is mainly based on petrographic and lithologic studies of samples from drill holes in Yucca Mountain. Clay minerals, zeolites, fluorite, and barite, as minerals that are produced economically in Nevada, have been identified in samples from drill holes in Yucca Mountain.

  6. Rock-forming mechanism of Fenghuangshan rockbody in Tongling area

    Institute of Scientific and Technical Information of China (English)

    邵拥军; 彭省临; 吴淦国; 刘亮明; 赖健清; 张达

    2003-01-01

    Based on the detailed geological investigation and record of galleries and drill holes, a new idea has beenadvanced that granodiorite is earlier than quartz monzodiorite porphyry. Both of them are products of two differentmagmatic intrusive activities. The analysis results of trace elements show that the Sr content is beyond any othercrustal rock and the Th content is beyond that of Ta. The whole-rock analysis indicates that rockbody is rich in CaOand poor in K2O. In the composition of Pb istope of rockbody, the ratio of 207Pb to 204Pb is less than 15.60. Allthese show that the magma mainly comes from the upper mantle. Ti,Zr,Cr,Nb trace elements and the relation be-tween the Gardini index(τ) and the Rittmann index(σ) indicate that the rockbodies are formed in the orogenic beltand island arc tectonic setting. The summation (∑REE) and the characteristic value (m (La)/m (Yb)) of the rareearth elements show that the original rock is alkalic basalt. The analysis of the characteristic values of REE and thequantitative modeling calculation indicate that the rock-forming process is dominated by mixed crystallization. Ac-cording to the analysis on the rock-forming order, magmatic source, tectonic setting and rock-forming process, com-bined with the achievements of regional rock-controlling structures and division of sublayer of crust, it is believedthat Fenghuangshan rock body derives from the deep-seated alkalic basalt magma. The rock-forming process has un-dertaken sialic and calcareous assimilation and contamination of two different degrees. The rock-forming model be-longs to the typical assimilation and fractional cryatalization mechanism.

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

    Science.gov (United States)

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

    2010-05-01

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

  8. Ultramafic rocks in the Namurian C series in the Zebrzydowice area (Rybnik coal region)

    Energy Technology Data Exchange (ETDEWEB)

    Jochemczyk, L.

    1984-08-01

    The chemical and physical properties as well as origin of ultramafic rock samples from the Zebrzydowice area in the Rybnik coal region are evaluated. The ultramafic rocks detected by drilling were situated at depths of 1035 m in the top of dacite-andesite system and thermally alterated claystones. Chemical analyses and X-ray examination show that the ultramafic rock consists of secondarily alterated peridotite. The peridotite consists of chlorite-serpentite, phlogopite, bastite, nepheline and opaque minerals. Its chemical composition is characterized by reduced content of silica and a high content of ferric oxide. The ultramafic rock in the Zebrzydowice area differs from mineral and chemical composition of igneous rocks which occur in Carboniferous strata in the west and the southwest of the Upper Silesia basin. Rock of this type has been recorded in the Upper Silesia basin for the first time. 12 references.

  9. Tests of Rock Cores Scott Study Area, Missouri

    Science.gov (United States)

    1970-05-01

    little potassium feldspar is present in these cores. The bulk composition of this rock is quartz, plagio - clase feldspar (near oligoclase), chlorite...rhyolite porphyry, containing quartz and equal amounts of potassium and plagio - clase feldspar. Piece 22 of PC-2 (Figure 4.8) and Piece 22 of DC-5 (Figure...representative of this type. The bulk composition was Plagio - clase, orthoclase, quartz, biotite, and chlorite. About one-third of the pieces of the core

  10. Research on inspection of stability of subsiding area in composite rock-mass roadway

    Institute of Scientific and Technical Information of China (English)

    来兴平

    2002-01-01

    The research concentrates mainly on the development of failure process in composite rock-mass through acoustic emission, convergence inspection, stress measurement, subside area measurement, level measurement in the process of stability and safety monitoring as well as inspecting of subside area in composite hard rock. In terms of the modern signal analysis technology, various aspects are discussed. The monitoring result and the stability of rock mass can be synthetically evaluated and inferred, and the location of acoustic origin according to the acoustic emission regularity can be successfully detected. Finally the key factors of the deformation can be inferred from in subside area.

  11. Rock shelters in Gorges Valley, Mount Kenya Afroalpine area

    Science.gov (United States)

    Mahaney, W. C.; Barendregt, R. W.; Churcher, C. S.; Spence, John R.

    Two rock shelters were located during the course of a field survey of important Quaternary sections on Mount Kenya. Located in dense riverine vegetation, in and around a sequence of end moraines, in the Ericaceous zone on the mountain, they appear to contain the remains of relatively recent ephemeral occupation by transient hunters. The origin of the shelters, their relationship to multiple glaciation on the mountain, and the remains of fragments and bones found in associated hearths are described and discussed. Fragments of wood and bone from a pigeon or dove? ( Streptopelia sp.) and from a small artiodactyl mammal (? Cephalophus grimmia) were recovered, some from within hearths.

  12. Rock samples and geochemical analyses of Afghanistan and adjacent areas (rockafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of rock samples (core samples and outcrop samples) collected in Afghanistan and adjacent areas, and the...

  13. Research on Diageneses of Cambrian Shoal Facies Carbonate Rocks in the Xiadong Area, Hubei Province

    Institute of Scientific and Technical Information of China (English)

    张秀莲; 蒋凌志

    2001-01-01

    With continuous outcrops, developed shoal facies rocks, complete types of diagenesis and changeable diagenetic environments, Cambrian strata are well developed in the Xiadong area, Yichang, Hubei Province. Under the combined influence of numerous diageneses, secondary pores can be formed, which result in better reservoir properties of the rock strata. The Cambrian rocks in this area consist of mainly carbonate rocks and secondarily detrital rocks. The carbonate rocks are dominated by grainstones including wormkalk, calcirudite-calcarenite, oolitic limestone and oncolitic limestone. Graded bedding and cross bedding are well developed in the strata, which indicates that the formation environment is of a high-energy shoal facies. In this area, there has developed a sequence of stable Cambrian platform carbonate deposition. The evolution trend is as follows: open sea shelf facies? intertidal low-energy restricted sea facies? intertidal high-energy shoal facies? coastal shoal facies? evaporite tidal-flat facies. The diageneses that the strata have experienced mainly include dolomitization, dedolomitization and dissolution, which are constructive diageneses for the formation of secondary pores, such as intercrystal pores, intercrystal solution pores, gypsum mold pores and caverns of dolomite. The diagenetic facies intervals can be divided into the unitary and the compound ones, totalling 22 in the area. In the early atmospheric fresh-water diagenetic environment and the late epidiagenetic environment, Cambrian rocks, especially dolomite of the Middle and Upper Cambrian, experienced extensive and profound fresh water corrosion, forming pore intervals with a porosity ranging from 5% to 15%.

  14. Late Neoproterozoic basement rocks of Meatiq area, Central Eastern Desert, Egypt: Petrography and remote sensing characterizations

    Science.gov (United States)

    Hassan, Safaa M.; El kazzaz, Yahiya A.; Taha, Maysa M. N.; Mohammad, Abdullah T.

    2017-07-01

    Meatiq dome is one of the mysteries of the basement rocks in Central Eastern Desert (CED) of Egypt. Its mode of formation, and tectonic evolution are still controversial and not fully understood. Satellite remote sensing is a powerful tool for geologic applications, especially in inaccessible regions of the Earth's surface. In this study, three proposed Landsat-8 band ratios (6/2, 6/7, (6/4*4/3)), (6/7, 6/4, 4/2), and (7/5, 7/6, 5/3) are successfully used for detailed geological mapping of the different lithological rock units exposed in Meatiq dome area in the CED. Landsat-8 Principal component (PC) images is also used for refinement the boundaries between the widely-exposed rock units in the study area. Fourteen spectral bands of Advanced Space borne Thermal Emission and Reflection Radiometer (ASTER) data are successfully used to emphasize the distribution of some rock forming minerals (i.e. muscovite, quartz, ferrous oxides, ferrous silicates and hydroxyl-bearing minerals) in the lithological rock units of Meatiq dome area. ASTER muscovite index (B7/B6) and quartz index (B14/B12), ferrous iron index (B5/B3), ferrous silicates index (B5/B4), mafic index (B12/B13) and hydroxyl-bearing minerals index ((B7/B6)*(B4/B6)) discriminate muscovite bearing rocks, Granitoids, and other felsic rocks, amphibolite and other mafic rocks. The proposed image processing methods effectively discriminates between four granitic varieties existed in Meatiq area. They are namely; Abu Ziran, Ariki, Fawakhir and Atalla Plutons. This study reveals that the applied data of ASTER and Landsat-8 enhanced images produced a modified geological map with well emphasized rock units which are verified with field observations, and petrographic study.

  15. A Petrographic and Mineralogical Study of Volcanic Rocks from the Mayaxueshan Area, North Qilian Fold Belt, NW China

    Institute of Scientific and Technical Information of China (English)

    徐达伟; 萧炎宏

    2002-01-01

    The Ordovician volcanic rocks in the Mayaxueshan area have been pervasively altered or metamorphosedand contain abundant secondary minerals such as albite, chlorite, epidote, prehnite, pumpellyite, actinolite, titanite, quartz,and/or calcite. They were denoted as spilites or spilitic rocks in terms of their petrographic features and mineral assem-blages. The metamorphic grades of the volcanic rocks are equivalent to that of the intercalated metaclastic rocks. Thisindicates that both the spilitic volcanic rocks and metaclastic rocks in the Mayaxueshan area have formed as a result ofCaledonian regional metamorphism. We suggest that the previously denoted spilitic rocks or altered volcanic rocks shouldbe re-denoted as metabasalts or metabasaltic rocks. The metamorphic grade of the volcanic rocks increases with their age:prehnite-pumpellyite facies for the upper part of the Middle Ordovician volcanic rocks, prehnite-pumpellyite to lowergreenschist facies for the lower part of the Middle Ordovician volcanic rocks, and lower greenschist facies for the LowerOrdovician volcanic rocks. The P-T conditions are estimated as T = 240 - 290C and P = 1.5 - 4.5 kbar for the lower partof the Middle Ordovician rocks, and T = ~ 300~C for the Lower Ordovician rocks. The variations of mineral assemblagesoccurring at different domains of the volcanic rocks were controlled by the variations of the effective bulk composition inthose domains during metamorphism. The geochemical characteristics of Mg-Al chromite in the Mayaxueshan volcanicrocks are consistent with an origin of island arc environment.

  16. Solid images generated from UAVs to analyze areas affected by rock falls

    Science.gov (United States)

    Giordan, Daniele; Manconi, Andrea; Allasia, Paolo; Baldo, Marco

    2015-04-01

    The study of rock fall affected areas is usually based on the recognition of principal joints families and the localization of potential instable sectors. This requires the acquisition of field data, although as the areas are barely accessible and field inspections are often very dangerous. For this reason, remote sensing systems can be considered as suitable alternative. Recently, Unmanned Aerial Vehicles (UAVs) have been proposed as platform to acquire the necessary information. Indeed, mini UAVs (in particular in the multi-rotors configuration) provide versatility for the acquisition from different points of view a large number of high resolution optical images, which can be used to generate high resolution digital models relevant to the study area. By considering the recent development of powerful user-friendly software and algorithms to process images acquired from UAVs, there is now a need to establish robust methodologies and best-practice guidelines for correct use of 3D models generated in the context of rock fall scenarios. In this work, we show how multi-rotor UAVs can be used to survey areas by rock fall during real emergency contexts. We present two examples of application located in northwestern Italy: the San Germano rock fall (Piemonte region) and the Moneglia rock fall (Liguria region). We acquired data from both terrestrial LiDAR and UAV, in order to compare digital elevation models generated with different remote sensing approaches. We evaluate the volume of the rock falls, identify the areas potentially unstable, and recognize the main joints families. The use on is not so developed but probably this approach can be considered the better solution for a structural investigation of large rock walls. We propose a methodology that jointly considers the Structure from Motion (SfM) approach for the generation of 3D solid images, and a geotechnical analysis for the identification of joint families and potential failure planes.

  17. Geochemistry of Eagle Ford group source rocks and oils from the first shot field area, Texas

    Science.gov (United States)

    Edman, Janell D.; Pitman, Janet K.; Hammes, Ursula

    2010-01-01

    Total organic carbon, Rock-Eval pyrolysis, and vitrinite reflectance analyses performed on Eagle Ford Group core and cuttings samples from the First Shot field area, Texas demonstrate these samples have sufficient quantity, quality, and maturity of organic matter to have generated oil. Furthermore, gas chromatography and biomarker analyses performed on Eagle Ford Group oils and source rock extracts as well as weight percent sulfur analyses on the oils indicate the source rock facies for most of the oils are fairly similar. Specifically, these source rock facies vary in lithology from shales to marls, contain elevated levels of sulfur, and were deposited in a marine environment under anoxic conditions. It is these First Shot Eagle Ford source facies that have generated the oils in the First Shot Field. However, in contrast to the generally similar source rock facies and organic matter, maturity varies from early oil window to late oil window in the study area, and these maturity variations have a pronounced effect on both the source rock and oil characteristics. Finally, most of the oils appear to have been generated locally and have not experienced long distance migration. 

  18. Magmatic Source Composition and Magmatism of the Volcanic Rocks in the Area of Kuruktag, Southern Xinjiang

    Institute of Scientific and Technical Information of China (English)

    JIANG Changyi; BAI Kaiyin; HI Aizhi; ZHAO Xiaoning; ZHANG Hongbo

    2001-01-01

    In the Sinian-Cambrian strata in the area of Kuruktag, southern Xingjiang, four layers of volcanic rocks occurred in the Early Sinian Beiyixi Formation, Late Sinian Zhamoketi Formation and Shuiquan Formation, and Early Cambrian Xishanbulake Formation, respectively. Volcanics of the Shuiquan Formation and Xishanbulake Formation are of alkali basalt series, those of the Zhamoketi Formation are of alkali basalt series and tholeiite series, and those of the Beiyixi Formation are obviously characterized by bimodal assemblage and mostly belong to alkali volcanics. Multi-element distribution patterns of the rocks show continental tumescence characters of interplate basalt.Fractional crystallization of plagioclase led to negative Eu-anomalies of some volcanics and the cumulation of olivine resulted in high MgO and low SiO2 content of some volcanic rocks. The SiO2 saturability of volcanic rocks of the Xishanbulake Formation and Shuiquan Formation is lower than that of tholeiite of the Zhamoketi Formation. Correspondingly, the abundance of incompatible elements in the first two formations is higher than those in the last formation, and the differences can be attributed to the different degrees of partial melting. The intense fractionation of REE and the obvious depletion of HREE suggest that these volcanic rocks were derived from garnet Iherzolite of the mantle in the continental lithosphere. The Ba/Nb, La/Nb, Ba/La, Ba/Th and Rb/Nb rations demonstrate that these volcanic rocks were exclusively derived from the enriched mantle, mainly the EMI type mantle.

  19. Analysis of microseismic signals and temperature recordings for rock slope stability investigations in high mountain areas

    Directory of Open Access Journals (Sweden)

    C. Occhiena

    2012-07-01

    Full Text Available The permafrost degradation is a probable cause for the increase of rock instabilities and rock falls observed in recent years in high mountain areas, particularly in the Alpine region. The phenomenon causes the thaw of the ice filling rock discontinuities; the water deriving from it subsequently freezes again inducing stresses in the rock mass that may lead, in the long term, to rock falls. To investigate these processes, a monitoring system composed by geophones and thermometers was installed in 2007 at the Carrel hut (3829 m a.s.l., Matterhorn, NW Alps. In 2010, in the framework of the Interreg 2007–2013 Alcotra project no. 56 MASSA, the monitoring system has been empowered and renovated in order to meet project needs.

    In this paper, the data recorded by this renewed system between 6 October 2010 and 5 October 2011 are presented and 329 selected microseismic events are analysed. The data processing has concerned the classification of the recorded signals, the analysis of their distribution in time and the identification of the most important trace characteristics in time and frequency domain. The interpretation of the results has evidenced a possible correlation between the temperature trend and the event occurrence.

    The research is still in progress and the data recording and interpretation are planned for a longer period to better investigate the spatial-temporal distribution of microseismic activity in the rock mass, with specific attention to the relation of microseismic activity with temperatures. The overall goal is to verify the possibility to set up an effective monitoring system for investigating the stability of a rock mass under permafrost conditions, in order to supply the researchers with useful data to better understand the relationship between temperature and rock mass stability and, possibly, the technicians with a valid tool for decision-making.

  20. Assessment of Performance for Alternative Cover Systems on a Waste Rock Storage Area

    Science.gov (United States)

    Argunhan, C.; Yazicigil, H.

    2015-12-01

    A cover is usually applied to the top of the mining wastes to prevent exposure of sulphide minerals in the waste to water and oxygen ingress in order to mitigate the unwanted consequences such as acid rock drainage. Hence, the selection and design of the appropriate cover system by considering the climatic conditions, local unsaturated and saturated properties and the availability of the cover materials become an important issue. This study aims to investigate the performance of various cover systems and designs for the North Waste Rock Storage Area in Kışladağ Gold Mine located in Uşak in Western Turkey. SEEP/W and VADOSE/W softwares are used to model the flow in unsaturated and saturated zones and to assess the performance of various cover systems. The soil water characteristics and parameters used in the model for saturated and unsaturated conditions were taken from field tests and literature. Accuracy of input data is checked during calibration for steady state conditions with SEEP/W. Then, bedrock, waste rock and cover alternatives are modeled under transient conditions for 20 years using daily climatic data. The effectiveness of the various cover systems for minimizing the ingress of water and air that cause acid rock drainage is evaluated and recommendations are made so that the impacts to groundwater from the waste rock storage areas during closure period are minimized.

  1. Hot dry rock geothermal potential of Roosevelt Hot Springs area: review of data and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    East, J.

    1981-05-01

    The Roosevelt Hot Springs area in west-central Utah possesses several features indicating potential for hot dry rock (HDR) geothermal development. The area is characterized by extensional tectonics and a high regional heat flow of greater than 105 mW/m/sup 2/. The presence of silicic volcanic rocks as young as 0.5 to 0.8 Myr and totaling 14 km/sup 3/ in volume indicates underlying magma reservoirs may be the heat source for the thermal anomaly. Several hot dry wells have been drilled on the periphery of the geothermal field. Information obtained on three of these deep wells shows that they have thermal gradients of 55 to 60/sup 0/C/km and bottom in impermeable Tertiary granitic and Precambrian gneissic units. The Tertiary granite is the preferred HDR reservoir rock because Precambrian gneissic rocks possess a well-developed banded foliation, making fracture control over the reservoir more difficult. Based on a fairly conservative estimate of 160 km/sup 2/ for the thermal anomaly present at Roosevelt Hot Springs, the area designated favorable for HDR geothermal exploration may be on the order of seven times or more than the hydrogeothermal area currently under development.

  2. High-grade metamorphic rocks of the Mellid area, Galicia, NW Spain

    NARCIS (Netherlands)

    Hubregtse, J.J.M.W.

    1973-01-01

    This study concerns the petrology of the Mellid area, the SE portion of the outer zone of the Ordenes Complex which is one of the upthrusted Precambrian complexes in the axial zone of the Hercynian orogen in Galicia, NW Spain. An eugeosynclinal rock sequence is found containing units with different

  3. Weathering of Carbonate Rocks by Biological Soil Crusts in Karst Areas

    Institute of Scientific and Technical Information of China (English)

    Ye Chen; Bin Lian; Zuoying Yin; Yuan Tang

    2014-01-01

    The weathering of carbonate rocks by biological soil crusts (BSC) in karst areas is very common. It is helpful to understand the weathering mechanisms and processes for avoiding karst rock-desertification. The weathering of carbonate rocks by BSC in karst areas, namely the expansion, contraction and curl resulting from environmental wetting-drying cycles, was investigated and ana-lyzed in this paper. The bulk density, area and thickness of BSC were determined and the weathering amount of limestone and dolomite per unit area of BSC was calculated as 3 700 and 3 400 g·m-2; the amount of biomass on the surface of limestone and dolomite was calculated as 1 146 and 1 301 g·m-2, respectively. Such an increased weathering amount was not only the result of chemical and physical weathering of BSC on carbonate rocks, but also the attachment and cementation of BSC to clay parti-cles, dust-fall, sand particles, solid particles brought by strong air currents, wind and other factors in the surrounding environment, which may also be related to the special environment and the special time period. Based on the results obtained, a weathering mode of BSC is studied, and the mechanisms of weathering by BSC are discussed. In conclusion, we suggest that the mechanical force exerted by the expansion and constriction of gelatinous and mucilaginous substances through wetting and drying of BSC play a significant role in the physical weathering process of the carbonate substrates.

  4. Pore-Scale Heterogeneity in the Mineral Distribution and Reactive Surface Area of Porous Rocks

    Science.gov (United States)

    Lai, P. E. P.; Krevor, S. C.

    2015-12-01

    The reactive surface area is an important control on interfacial processes between minerals and aqueous fluids in porous rocks. Spatial heterogeneity in the surface area can lead to complications in modelling reactive transport processes, but quantitative characterisation of this property has been limited. In this paper 3D images obtained using x-ray micro-tomography were used to characterise heterogeneity in surface area in one sandstone and five carbonate rocks. Measurements of average surface area from x-ray imagery were 1-2 orders of magnitude lower than measurements from nitrogen BET. A roughness factor, defined as the ratio of BET surface area to x-ray based surface area, was correlated to the presence of clay or microporosity. Coregistered images of Berea sandstone from x-ray and energy dispersive spectroscopy imagery were used to guide the identification of quartz, K-feldspar, dolomite, calcite and clays in x-ray images. In Berea sandstone, clay and K-feldspar had higher average surface area fractions than their volumetric fractions in the rock. In the Edwards carbonate, however, modal mineral composition correlated with surface area. By sub-sampling digital images, statistical distributions of the surface area were generated at various length scales of subsampling. Comparing these to distributions used in published modelling studies showed that the common practice of leaving surface area and pore volume uncorrelated in a pore leads to unrealistic combinations of surface area and pore volume in the models. We suggest these models adopt a moderate correlation based on observations. In Berea sandstone, constraining ratios of surface area to pore volume to a range of values between that of quartz-lined and five times that of clay-lined spheres appeared sufficient.

  5. Characteristics of algal succession following rock scraping at Imwon area in the east coast of Korea

    Science.gov (United States)

    Kim, Young Dae; Ahn, Jung Kwan; Nam, Myung Mo; Lee, Chu; Yoo, Hyun Il; Yeon, Su Yeoung; Kim, Young Hwan; Kim, Jang Kyun; Choi, Jae Suk

    2016-12-01

    This study was conducted to clarify the characteristics of algal succession following rock scraping using hoe or high-pressure water sprayer in the period from June 2010 to April 2011. We divided the research area off the eastern coast of Korean near Imwon into 3 categories depending upon the severity of the barren ground, i.e., the urchin barren-affected, urchin barren-ongoing and urchin barren-free areas. In April 2011, in the urchin barren-affected area with 25 seaweed species, the cover percentage and importance value (IV) of crustose coralline algae were higher than those of other species. In the urchin barren-ongoing area with 33 seaweed species, crustose coralline algae (mean IV = 62%) as well as Sargassum sp. (mean IV = 28%), and Gelidium amansii (mean IV = 19%) were observed following rock scraping. In the urchin barren-free area where seaweed communities were relatively abundant with 42 species, a variety of algal species including G. amansii (mean IV = 32%) underwent algal succession. Overall, it was observed that, as an aspect of algal succession, the weaker the barren ground severity was, the more frequent and diverse the seaweeds were, and the more complex the succession pattern was in the study. As an aspect of recovering algal community, rock scraping using hoe was shown to be superior to the method using high-pressure water spraying. Therefore, we conclude that rock scraping using hoe is a very effective strategy for recovering the algal community in urchin barren-ongoing area.

  6. Characteristics of Algal Succession Following Rock Scraping at Imwon Area in the East Coast of Korea

    Institute of Scientific and Technical Information of China (English)

    Young Dae Kim; Jung Kwan Ahn; Myung Mo Nam; Chu Lee; Hyun Il Yoo; Su Yeoung Yeon; Young Hwan Kim; Jang Kyun Kim; Jae Suk Choi

    2016-01-01

    This study was conducted to clarify the characteristics of algal succession following rock scraping using hoe or high-pressure water sprayer in the period from June 2010 to April 2011. We divided the research area off the eastern coast of Korean near Imwon into 3 categories depending upon the severity of the barren ground,i.e., the urchin barren-affected, urchin bar-ren-ongoing and urchin barren-free areas. In April 2011, in the urchin barren-affected area with 25 seaweed species, the cover per-centage and importance value (IV) of crustose coralline algae were higher than those of other species. In the urchin barren-ongoing area with 33 seaweed species, crustose coralline algae (mean IV=62%) as well asSargassumsp. (mean IV=28%), andGelidium amansii (mean IV=19%) were observed following rock scraping. In the urchin barren-free area where seaweed communities were relatively abundant with 42 species, a variety of algal species includingG. amansii (mean IV=32%) underwent algal succession. Overall, it was observed that, as an aspect of algal succession, the weaker the barren ground severity was, the more frequent and di-verse the seaweeds were, and the more complex the succession pattern was in the study. As an aspect of recovering algal community, rock scraping using hoe was shown to be superior to the method using high-pressure water spraying. Therefore, we conclude that rock scraping using hoe is a very effective strategy for recovering the algal community in urchin barren-ongoing area.

  7. Lithium in rocks from the Lincoln, Helena, and Townsend areas, Montana

    Science.gov (United States)

    Brenner-Tourtelot, Elizabeth F.; Meier, Allen L.; Curtis, Craig A.

    1978-01-01

    In anticipation of increased demand for lithium for energy-related uses, the U.S. Geological Survey has been appraising the lithium resources of the United States and investigating occurrences of lithium. Analyses of samples of chiefly lacustrine rocks of Oligocene age collected by M. R. Mudge near Lincoln, Mont. showed as much as 1,500 ppm lithium. Since then we have sampled the area in greater detail, and have sampled rocks of similar ages in the Helena and Townsend valleys. The lithium-rich beds crop out in a band about 1.3 km long by 0.3 km wide near the head of Beaver Creek, about 14 km northwest of Lincoln, Mont. These beds consist of laminated marlstone, oil shale, carbonaceous shale, limestone, conglomerate, and tuff. Some parts of this sequence average almost 0.1 percent lithium. The lithium-bearing rocks are too low in grade and volume to be economic. Samples of sedimentary rocks of Oligocene age from the Helena and Townsend valleys in the vicinity of Helena, Mont. were generally low in lithium (3-40 ppm). However, samples of rhyolites from the western side of the Helena valley and from the Lava Mountain area were slightly above average in lithium content (6-200 ppm).

  8. Characteristics of Magmatic Rocks and Tectonic Setting of Mazhuangshan Area,East Tianshan,China

    Institute of Scientific and Technical Information of China (English)

    陈世忠; 周济元; 等

    2000-01-01

    The Mazhuangshan area lies in northeast to Aqikekuduke,where are distributed in-termediate-acid rocks,which were formed in the Middle-Late Carboniferous epoch.The magmatic rocks are peraluminous and belong to calcareous series.All values of ACNK(1.03-2.12),ANK(1.67-2.93),SI(4.1-33),δ(0.71-4.82),La/∑REE(0.09-0.26) ∑LREE/∑HREE(1.76-11.01),(La/Sm)N(1.60-6.35),(Sm/Nd)N(0.33-0.58),(La/Yb)N(4.7-12.1),LaN/Lux(5.9-11.8),(Ce/Yb)N(3.14-6.64),δEu(0.38-1.06),RbN/SrN(41-120)and Sr(0.02-0.2)demonstrate they vary with D_I(45-90).S-B diagram also shows that the lithophile elements are abundant in acidic magmatic rocks,Moreover,it is concluded that the primitive magma originated from a subduction zone at the continental edge,and underwent fractional crystallization and contamination,then generated the magmatic rocks,The multi-cation index(R:3055-3993,R2:286-438) shows that the primitive magma originated from the mantle,All these conclusions are beneficial for exploring gold deposits in the area.

  9. Extreme Mantle Heterogeneity beneath the Jingpohu Area, Northeastern China-Geochemical Evidence of Holocene Basaltic Rock

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Holocene basaltic rocks of the Jingpohu area are located in the "Crater Forest" and Hamatang districts to the northwest of the Jingpohu Lake. Although there is only a distance of 15 km between the two districts, their petrological characteristics are very different: alkaline olivine basalt without any megacrysts in the former, and leucite tephrite with Ti-amphibole, phlogopite and anorthoclasite megacrysts in the latter. On the basis of their geochemical characteristics, the two types of basaltic rocks should belong to weakly sodian alkaline basalts. But leucite tephrite is characterized by higher Al2O3, Na2O and K2O, higher enrichment in light rare earth elements (LREE) and large ion lithophile elements (LILE), lower MgO and CaO, compatible elements and moderately compatible elements and lower Mg# values and Na/K ratios in comparison with alkaline olivine basalt. However, the two types of basaltic rocks have similar Sr, Nd, Pb isotopic compositions, which suggests that the mantle beneath the Jingpohu area was homogeneous before undergoing some geological processes about 3490 years ago. As the activity of the mantle plume led to different degrees of metasomatism, extreme mantle source heterogeneities occurred beneath the Jingpohu area. In comparison with alkaline olivine basalt, the leucite tephrite was derived from the more enriched mantle source region and resulted from strong metasomatism.

  10. Pore scale heterogeneity in the mineral distribution and reactive surface area of rocks

    Science.gov (United States)

    Lai, P. E.; Krevor, S. C.

    2013-12-01

    There are long-standing challenges in characterizing reactive transport in porous media at scales larger than individual pores. This hampers the prediction of the field-scale impact of geochemical processes on fluid flow [1]. This is a source of uncertainty for CO2 injection, which results in a reactive fluid-rock system, particularly in carbonate rock reservoirs. A potential cause is the inability of the continuum approach to incorporate the impact of heterogeneity in pore-scale reaction rates. This results in part from pore-scale heterogeneities in surface area of reactive minerals [2,3]. In this study we have created μm resolution 3D images of 3 sandstone and 4 carbonate rocks using x-ray microtomography. Using in-house image processing techniques and auxiliary characterisation with thin section, electron microscope and spectroscopic techniques we quantified the surface area of each mineral phase in the x-ray CT images. This quantification was validated against N2 BET surface area and He porosity measurements of the imaged samples. Distributions in reactive surface area for each mineral phase were constructed by calculating surface areas in thousands of randomly selected subvolume images of the total sample, each normalized to the pore volume in that image. In all samples, there is little correlation between the reactive surface area fraction and the volumetric fraction of a mineral in a bulk rock. Berea sandstone was far less heterogeneous and has a characteristic pore size at which a surface area distribution may be used to quantify heterogeneity. In carbonates, heterogeneity is more complex and surface area must be characterized at multiple length scales for an accurate description of reactive transport. [1] Maher, Steefel, Depaolo and Vianni (2006) Geochimica et Cosmochimica Acta, 70, 337-363 [2] Landrot, Ajo-Franklin, Yang, Cabrini and Steefel (2012) Chemical Geology 318-319, 113-125 [3] Li, Peters and Celia (2007) American Journal of Science 307, 1146

  11. Supracrustal rocks in the Kuovila area, Southern Finland: structural evolution, geochemical characteristics and the age of volcanism

    OpenAIRE

    Pietari Skyttä; Asko Käpyaho; Irmeli Mänttäri

    2005-01-01

    The supracrustal rocks of the Kuovila area in the Palaeoproterozoic Svecofennian Uusimaa Belt, southern Finland, consist mainly of volcaniclastic rocks associated with banded iron formations (BIFs) and marbles. Small ZnS and PbS mineralizations are occasionally located within the marbles. Some primary features are well preserved in the sedimentary and volcanic rocks, including lamination in tuffites and banded iron formations. Geochemical results show that the volcanism was bimodal and it mai...

  12. Utilization of remote sensing methods in prospecting of alkaline rocks in Finland and neighbouring areas

    Directory of Open Access Journals (Sweden)

    Paarma, H.

    1996-06-01

    Full Text Available The availability of various kind of satellite imageries and geological, geochemical and geophysical data in useful form has given possibility to confirm the earlier tectonic interpretations of deep fracture zones and to find new interesting zones for the exploring of alkaline rocks in Finland. The interpretations and suggestions given here are tentative prognoses for prospecting certain areas. The selecting of real target areas need more work. Some methods for this kind of classifying research for planning prospecting projects have been recommended. So far the Finnish Lapland is regarded as a region where the methods suggested here would give useful results.

  13. Diagenetic Pattern in the Citarate Carbonate Rocks, Cilograng Area, Lebak Regency, Banten Province

    Directory of Open Access Journals (Sweden)

    N. I. Basuki

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v7i3.142The carbonate sequence overlies conformably the tuffaceous sandstone unit, and in turn is conformably underlain by the tuff-sandstone unit, both of which are members of the Citarate Formation. The Citarate carbonate rocks were deposited in an open platform back reef environment, which was temporarily drowned by local sea level rise. Regional Middle Miocene deformation formed NNE-WSW trend faults and E-W trend folds in the researched area. This paper discusses the nature of diagenetic alteration of the Citarate carbonate rocks based on petrographic analyses of twenty surface samples. Carbonate rocks from bottom to top comprise algae packstone, packstone-grainstone, coral-algae packstone, and foraminifer wackestone-packstone. Fragments of coral, coralline red algae, and large foraminifera are the dominant bioclasts in most of the observed samples, whereas echinoids and bivalves are less abundant; they are set in a recrystallized micrite matrix. Planktonic foraminifera are abundant only in few samples. Fragments of plagioclase, igneous volcanic rocks, pyroclastic rocks (tuff, and much less abundant quartz are commonly present in all the studied samples. A generalized diagenesis includes early marine cementation by fibrous aragonite, compaction, aragonite dissolution and/or neomorphism, precipitation of equant-grained calcite cement in a phreatic environment, dissolution to form moldic porosities, dolomitization, the formation of stylolites and fractures, and precipitation of late ferroan calcite during burial. Multiple carbonate cements occur as pore-filling phases, with ferroan calcite cementation taking place during later-stage burial. Secondary porosities were formed during different stages in diagenetic processes, such as dissolution, dolomitization, and stylolite and fracture formations. Although precipitation of nonferroan and ferroan calcite cement occluded porosities, porosity enhancement during early selective

  14. Diagenetic Pattern in the Citarate Carbonate Rocks, Cilograng Area, Lebak Regency, Banten Province

    Directory of Open Access Journals (Sweden)

    N. I. Basuki

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v7i3.142The carbonate sequence overlies conformably the tuffaceous sandstone unit, and in turn is conformably underlain by the tuff-sandstone unit, both of which are members of the Citarate Formation. The Citarate carbonate rocks were deposited in an open platform back reef environment, which was temporarily drowned by local sea level rise. Regional Middle Miocene deformation formed NNE-WSW trend faults and E-W trend folds in the researched area. This paper discusses the nature of diagenetic alteration of the Citarate carbonate rocks based on petrographic analyses of twenty surface samples. Carbonate rocks from bottom to top comprise algae packstone, packstone-grainstone, coral-algae packstone, and foraminifer wackestone-packstone. Fragments of coral, coralline red algae, and large foraminifera are the dominant bioclasts in most of the observed samples, whereas echinoids and bivalves are less abundant; they are set in a recrystallized micrite matrix. Planktonic foraminifera are abundant only in few samples. Fragments of plagioclase, igneous volcanic rocks, pyroclastic rocks (tuff, and much less abundant quartz are commonly present in all the studied samples. A generalized diagenesis includes early marine cementation by fibrous aragonite, compaction, aragonite dissolution and/or neomorphism, precipitation of equant-grained calcite cement in a phreatic environment, dissolution to form moldic porosities, dolomitization, the formation of stylolites and fractures, and precipitation of late ferroan calcite during burial. Multiple carbonate cements occur as pore-filling phases, with ferroan calcite cementation taking place during later-stage burial. Secondary porosities were formed during different stages in diagenetic processes, such as dissolution, dolomitization, and stylolite and fracture formations. Although precipitation of nonferroan and ferroan calcite cement occluded porosities, porosity enhancement during early selective

  15. Environmental Assessment of a proposed reconstruction of the Lower Red Rock Lake dam : Red Rock Lakes National Wildlife Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Environmental Assessment (EA) for the renovation and attendant modifications to a water control dike on Red Rock Lakes National Wildlife Refuge, Montana. Completion...

  16. Hot dry rock resources of the Clear Lake Area, Northern California

    Energy Technology Data Exchange (ETDEWEB)

    Burns, K.L.

    1994-10-01

    The Geysers-Clear Lake geothermal area of northern California is underlain by an asthenospheric upwarp. The upwarp was generated at a slabless window trailing the northward-moving Mendocino triple junction. The geothermal area lies immediately east of the Rodgers Creek rather than the San Andreas fault because of a transform jump in progress. Decompression melting of the mantle has led to basaltic underplating, and crustal anatexis. The high heat flow is due to conduction through a thin lithosphere and the latent heat of solidifying basalt, while the uniformity is due to the distribution of sources over a wide area of large flatlying sills, The Hot Dry Rock resource has heat flow exceeding 4 HFU over an area exceeding 800 km2.

  17. Evaluation of the hot-dry-rock geothermal potential of an area near Mountain Home, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Arney, B.H.; Goff, F.

    1982-05-01

    Evaluation of an area near Mountain Home, Idaho, was performed to assess the hot dry rock (HDR) potential of the prospect. The techniques reported include telluric and gravity profiling, passive seismic, hydrology and water chemistry surveys, and lineament analysis. Gravity and telluric surveys were unsuccessful in locating fractures buried beneath recent volcanics and sediments of the plain because density and conductivity contrasts were insufficient. Gravity modeling indicated areas where granite was not likely to be within drilling depth, and telluric profiling revealed an area in the northwest part of the prospect where higher conductivity suggested the presence of fractures or water or both, thereby making it unsuitable for HDR. Water geochemistry indicated that (hot water) reservoir temperatures do not exceed 100/sup 0/C. An area in the east central part of the prospect was delineated as most favorable for HDR development. Temperature is expected to be 200/sup 0/C at 3-km depth, and granitic rock of the Idaho Batholith should be intersected at 2- to 3-km depth.

  18. Orogenic gold mineralisation hosted by Archaean basement rocks at Sortekap, Kangerlussuaq area, East Greenland

    Science.gov (United States)

    Holwell, D. A.; Jenkin, G. R. T.; Butterworth, K. G.; Abraham-James, T.; Boyce, A. J.

    2013-04-01

    A gold-bearing quartz vein system has been identified in Archaean basement rocks at Sortekap in the Kangerlussuaq region of east Greenland, 35 km north-northeast of the Skaergaard Intrusion. This constitutes the first recorded occurrence of Au mineralisation in the metamorphic basement rocks of east Greenland. The mineralisation can be classified as orogenic style, quartz vein-hosted Au mineralisation. Two vein types have been identified based on their alteration styles and the presence of Au mineralisation. Mineralised type 1 veins occur within sheared supracrustal units and are hosted by garnet-bearing amphibolites, with associated felsic and ultramafic intrusions. Gold is present as native Au and Au-rich electrum together with arsenopyrite and minor pyrite and chalcopyrite in thin alteration selvages in the immediate wall rocks. The alteration assemblage of actinolite-clinozoisite-muscovite-titanite-scheelite-arsenopyrite-pyrite is considered to be a greenschist facies assemblage. The timing of mineralisation is therefore interpreted as being later and separate event to the peak amphibolite facies metamorphism of the host rocks. Type 2 quartz veins are barren of mineralisation, lack significant alteration of the wall rocks and are considered to be later stage. Fluid inclusion microthermometry of the quartz reveals three separate fluids, including a high temperature ( T h = 300-350 °C), H2O-CO2-CH4 fluid present only in type 1 veins that in interpreted to be responsible for the main stage of Au deposition and sulphidic wall rock alteration. It is likely that the carbonic fluids were actually trapped at temperatures closer to 400 °C. Two other fluids were identified within both vein types, which comprise low temperature (100-200 °C) brines, with salinities of 13-25 wt% eq. NaCl and at least one generation of low salinity aqueous fluids. The sources and timings of the secondary fluids are currently equivocal but they may be related to the emplacement of

  19. Pore Scale Heterogeneity in the Mineral Distribution, Surface Area and Adsorption in Porous Rocks

    Science.gov (United States)

    Lai, P. E. P.; Krevor, S. C.

    2014-12-01

    The impact of heterogeneity in chemical transport and reaction is not understood in continuum (Darcy/Fickian) models of reactive transport. This is manifested in well-known problems such as scale dependent dispersion and discrepancies in reaction rate observations made at laboratory and field scales [1]. Additionally, this is a source of uncertainty for carbon dioxide injection, which produces a reactive fluid-rock system particularly in carbonate rock reservoirs. A potential cause is the inability of the continuum approach to incorporate the impact of heterogeneity in pore-scale reaction rates. This results in part from pore-scale heterogeneities in surface area of reactive minerals [2, 3]. We use x-ray micro tomography to describe the non-normal 3-dimensional distribution of reactive surface area within a porous medium according to distinct mineral groups. Using in-house image processing techniques, thin sections, nitrogen BET surface area, backscattered electron imaging and energy dispersive spectroscopy, we compare the surface area of each mineral phase to those obtained from x-ray CT imagery. In all samples, there is little correlation between the reactive surface area fraction and the volumetric fraction of a mineral in a bulk rock. Berea sandstone was far less heterogeneous and has a characteristic pore size at which a surface area distribution may be used to quantify heterogeneity. In carbonates, heterogeneity is more complex and surface area must be characterized at multiple length scales for an accurate description of reactive transport. We combine the mineral specific surface area characterisation to dynamic tomography, imaging the flow of water and solutes, to observe flow dependent and mineral specific adsorption. The observations may contribute to the incorporation of experimentally based statistical descriptions of pore scale heterogeneity in reactive transport into upscaled models, moving it closer to predictive capabilities for field scale

  20. Geochemical characteristics of Cenozoic high-K igneous rocks from Liuhe-Xiangduo area, eastern Tibet

    Institute of Scientific and Technical Information of China (English)

    WEI Qirong; WANG Jianghai

    2005-01-01

    The major elements, trace elements and Nd-Sr isotopic composition of Cenozoic high-K igneous rocks and mafic deep-derived enclaves from the Liuhe-Xiangduo area, eastern Tibet, indicate the high-K igneous rocks are characterized as being enriched in Ca (CaO= 1.20% - 8.80% ), alkali (Na2O+K2O= 3.47% - 10.65% ), especially K (K2O up to 5.96% ) and depleted in Ti (TiO2= 0.27% - 1.50% ). Their REE contents are very high (REE= 91.29 - 231.11 μg/g). Their REE distribution patterns are of the right-inclined type, characterized by intense LREE enrichment [(La/Yb)N= 7.44 - 15.73 ]. The rocks are distinctly enriched in Rb, Sr and Ba ( 46.3 -316 μg/g, 349-1220 μg/g and 386-2394 μg/g, respectively), high in U and Th ( 1.17 - 8.10 μg/g and 2.58 - 27.0 μg/g, respectively), moderate in Zr and Hf ( 87.5 -241 μg/g and 2.83 - 7.52 μg/g, respectively), and depleted in Nb and Ta ( 4.81 - 16.8 μg/g and 0.332 - 1.04 μg/g, respectively). In the primitive mantle-normalized incompatible element spidergram, U, K, Sr and Hf show positive anomalies, whereas Th, Nb, Ta, P, and Ti show negative anomalies. The rocks are strongly depleted in Cr and Ni ( 21.4 -1470 μg/g and 7.79 -562 μg/g, respectively), and their transition element distribution curves are obviously of type-W. The ( 87 Sr/ 86 Sr)i ratios range from 0.704184 to 0.707539 ; ( 143 Nd / 144 Nd)i from 0.512265 to 0.512564 ; and ε Nd (t) from -6.3 to -0.4 . These geochemical features might suggest that the potential source of the high-K igneous rocks in the Liuhe-Xiangduo area is similar to the EM2, which may be similar to the material enriched K that is located under the crust-mantle mixed layer. The mafic deep-derived enclaves in the high-K igneous rocks belong to chance xenoliths. Their ( 87 Sr/ 86 Sr)i ratios range from 0.706314 to 0.707198 ; ( 143 Nd / 144 Nd)i from 0.512947 to 0.513046 ; and ε Nd (t) from +7.0 to +9.0 . These geochemical features might indicate that the enclaves probably came from the depleted mantle

  1. Detailed gravity and aeromagnetic surveys in the Black Rock Desert Area, Utah. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Serpa, L.F.; Cook, K.L.

    1980-01-01

    Aeromagnetic and gravity surveys were conducted during 1978 in the Black Rock Desert, Utah over an area of about 2400 km/sup 2/ between the north-trending Pavant and Cricket Mountains. The surveys assisted in evaluating the geothermal resources in the Meadow-Hatton Known Geothermal Resource Area (KGRA) and vicinity by delineating geophysical characteristics of the subsurface. The gravity measurements from approximately 700 new stations were reduced to complete Bouguer gravity anomaly values with the aid of a computerized terrain-correction program and contoured at an interval of 1 milligal. The aeromagnetic survey was drape flown at an altitude of 305 m (1000 ft) and a total intensity residual aeromagnetic map with a contour interval of 20 gammas was produced. Two gravity and aeromagnetic east-west profiles and one north-south profile were modeled using a simultaneous 2 1/2-dimensional modeling technique to provide a single model satisfying both types of geophysical data.

  2. Mass wasting process at the surface of the Sangun metamorphic rocks in Kaminishigawa area, Asahi-machi, Okayama Prefecture.

    OpenAIRE

    新宮原, 秀和; 平山, 恭之; 津島, 淳; 於保, 幸正

    1999-01-01

    The relation among microstructures, weathering and mass wasting of the Sangun metamorphic rocks in the Kaminishigawa area, Asahi-machi, Okayama Prefecture, was studied. Three stages of penetrative planar structures are recognized; S1 schistosity, S2 crenulation cleavage and S3 crenulation cleavage. The S2 cleavage is the most commonly observed structure. The deree of weathering is divided into two classes on the base of appearance; slightly weathered and highly weathered rock. The three types...

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

    Science.gov (United States)

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

    1998-01-01

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

  4. Fluid-rock interaction controlling clay-mineral crystallization in quartz-rich rocks and its influence on the seismicity of the Carboneras fault area (SE Spain)

    Science.gov (United States)

    Jimenez-Espinosa, R.; Abad, I.; Jimenez-Millan, J.; Lorite-Herrera, M.

    2009-04-01

    are characterised also by the presence of dolomite and gypsum. The deformation is highly localized, developing phyllosilicate-rich bands highly foliated due to the presence of fine-sized aligned clays (chlorite and mica). In some undeformed lenses of the cataclastic rocks, variable-sized patches of phyllosilicates containing random oriented stacks of chlorite and mica are developed. BSE images reveal that the stacks are made of two intergrown compositional types of chlorite. These results lead to conclude that limited clay growth during faulting occurred. The absence of significant compositional differences between undeformed and deformed phyllosilicates suggests that whereas fluids were present during strike-slip faulting, fluids were not preferentially focused along the quartz-rich rocks of the fault zone by phyllosilicates avoiding the development of the synkinematic clay alteration process. However, clays played an important role for the mechanical behaviour of the quartzitic rocks in the fault zone. Deformation is highly localized in chlorite-rich sandstones. These sandstones show substantial clay crystallization which texture can be related with a hydrothermal origin before strike-slip faulting, likely associated with the volcanic activity of the area leading to form of chlorite/mica patches. These data indicate that, although elevated fluid pressure confined by clay fabric cannot be appealed for the mechanical behaviour of the sandstones of the Carboneras fault, clay fabrics developed during deformation dominated the fault-weakening mechanism. We consider that lubricating properties of phyllosilicates in the quartzitic rocks were an important factor controlling movement mechanisms promoting the predominance of creep as regards seismic stick-slip (Bedrosian et al., 2004) reducing the possibility of larger seismogenic events that nucleate on localized fault planes developed within quartzitic rocks contained within the fault zone. Finally the crystallization of

  5. Combined rock slope stability and shallow landslide susceptibility assessment of the Jasmund cliff area (Rügen Island, Germany

    Directory of Open Access Journals (Sweden)

    A. Günther

    2009-05-01

    Full Text Available In this contribution we evaluated both the structurally-controlled failure susceptibility of the fractured Cretaceous chalk rocks and the topographically-controlled shallow landslide susceptibility of the overlying glacial sediments for the Jasmund cliff area on Rügen Island, Germany. We employed a combined methodology involving spatially distributed kinematical rock slope failure testing with tectonic fabric data, and both physically- and inventory-based shallow landslide susceptibility analysis. The rock slope failure susceptibility model identifies areas of recent cliff collapses, confirming its value in predicting the locations of future failures. The model reveals that toppling is the most important failure type in the Cretaceous chalk rocks of the area. The shallow landslide susceptibility analysis involves a physically-based slope stability evaluation which utilizes material strength and hydraulic conductivity data, and a bivariate landslide susceptibility analysis exploiting landslide inventory data and thematic information on ground conditioning factors. Both models show reasonable success rates when evaluated with the available inventory data, and an attempt was made to combine the individual models to prepare a map displaying both terrain instability and landslide susceptibility. This combination highlights unstable cliff portions lacking discrete landslide areas as well as cliff sections highly affected by past landslide events. Through a spatial integration of the rock slope failure susceptibility model with the combined shallow landslide assessment we produced a comprehensive landslide susceptibility map for the Jasmund cliff area.

  6. Saddle-shaped reticulate Nummulites from Early Oligocene rocks of Khari area, SW Kutch, India

    Indian Academy of Sciences (India)

    S Sengupta; Sampa Sarkar; S Mukhopadhyay

    2011-04-01

    Saddle-shaped reticulate Nummulites from the Early Oligocene rocks of Khari area, SW Kutch, India is reported here for the first time. Unusual shape of this Nummulites is due to the curved nature of the coiling plane, indicating space constrained postembryonic test growth. With regular development of chambers, septa and septal filaments, the saddle-shaped Nummulites constitutes the third morphotype of N. cf. fichteli Michelotti form A. Other morphotypes of the species reported earlier include inflated lenticular and conical tests. Multiple morphotypes of N. cf. fichteli form A indicates varied test growth in response to substrate conditions. Morphological variability exhibited by N. cf. fichteli form A from Kutch and some Early Oligocene reticulate Nummulites from the Far East are comparable. This faunal suite is morphologically distinct from the contemporary reticulate Nummulites of the European localities.

  7. Changes in porosity, permeability and surface area during rock dissolution: effects of mineralogical heterogeneity

    CERN Document Server

    Min, Ting; Chen, Li; Kang, Qinjun; Tao, Wen-Quan

    2015-01-01

    Effects of heterogeneity of mineral distribution and reaction rate on the rock dissolution process are investigated using a pore-scale reactive transport model based on the lattice Boltzmann method. Coupled fluid flow, species transport, chemical reaction and solid structure alternation due to dissolution are simulated. Effects of mineral distributions and chemical heterogeneity on the dissolution behaviors and evolutions of hydrologic properties are studied under different reactive transport conditions. Simulation results show that the coupling between advection, diffusion and reaction as well as the mineralogical heterogeneity leads to complex reactive transport behaviors and complicated temporal evolutions of hydrologic properties including porosity, permeability and reactive surface. Diverse relationships between surface area and volume are predicted, which cannot be described by simple models such as the spherical-grain model. Porosity-permeability relationships also differ under different mineral distri...

  8. Geochemical Characteristics of Danfeng Meta-Volcanic Rocks in Shangzhou Area,Shaanxi Province

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    The Danfeng meta-volcanics in the Shangzhou area, Shaanxi Province are characterized by oceanic island arc volcanic geochemistry. They are a suite of low-K tholeiitic series and calc-alkaline series meta-volcanic rocks derived from different sources respectively.These meta-volcanics have high Th/Ta ratios and low contents of Ni,Ta,Ti,Y and Yb, suggesting that they were influenced by the subduction zone components.Many lines of evidence show that the Danfeng meta-volcanics were produced in an oceanic island are setting of the supra-subduction zone at the southern margin of the North China Block during the Early Paleozoic.

  9. Helminths of the exotic lizard Hemidactylus mabouia from a rock outcrop area in southeastern Brazil.

    Science.gov (United States)

    Anjos, L A; Rocha, C F D; Vrcibradic, D; Vicente, J J

    2005-12-01

    The helminth fauna of 291 Hemidactylus mabouia (Lacertilia: Gekkonidae) from a rock outcrop area in the state of São Paulo, Southeastern Brazil, was studied. Five species were recovered, namely one unidentified species of centrorhynchid acanthocephalan (present only as cystacanths) and the nematodes Parapharyngodon sceleratus, P. largitor (Oxyuroidea: Pharingodonidae), Physaloptera sp. (Spiruroidea: Physalopteridae) and one indeterminate species of Acuariidae (Acuaroidea), with the latter two forms present only as larvae. Infection rates tended to increase with host size, but appeared to be unaffected by season. Hemidactylus mabouia shared most of its helminth fauna with two other sympatric lizard hosts, Mabuya frenata and Tropidurus itambere. The helminth assemblage of the H. mabouia population appears to have been entirely acquired by this exotic gecko from the local helminth species pool, rather than possessing any species from the parasite faunas of the original African populations.

  10. Source-rock evaluation of the Dakhla Formation black shale in Gebel Duwi, Quseir area, Egypt

    Science.gov (United States)

    El Kammar, M. M.

    2015-04-01

    A relatively thick Upper Cretaceous-Lower Tertiary sedimentary succession is exposed in Gebel Duwi, Red Sea area, through an almost horizontal tunnel cutting the NE dipping strata from Quseir to Thebes formations. The black shale belonging to Dakhla Formation represents a real potential for future energy resource for Egypt. Dakhla Formation consists mainly of organic-rich calcareous shale to argillaceous limestone that can be considered as a good to excellent source rock potential. The total organic carbon (TOC) content ranges from 2.04% to 12.08%, and the Hydrogen Index (HI) values range from 382 to 1024 mg HC/g TOC. Samples of the Dakhla Formation contain mostly kerogen of types I and II that prone oil and oil-gas, indicating marine organic matter derived mainly from algae and phytoplankton organisms and proposing typical oil source kerogen. The average of the potential index (PI) value is 0.02 mg HC/g rock, which indicates the beginning of a considerable amount of oil generation from the Dakhla Formation. The Tmax values range from 427 to 435 °C. Based on the Tmax data and PI values, the studied black shale samples are immature to early mature for hydrocarbon generation in the Duwi area. The data reduction suggests four main factors covering about 91% of the total variances. The average of the calorific value (459 kcal/kg) indicates unworkable efficiency of such black shale for direct combustion use in power stations. However, selective operation of specific horizons having the highest calorific values may provide viable resources.

  11. Mineral chemistry of garnet in pegmatite and metamorphic rocks in the Hamedan area

    Directory of Open Access Journals (Sweden)

    Ahmad Ahmadi Khalaji

    2015-10-01

    Full Text Available Introduction The area of this study is located near Hamadan within the Sanandaj - Sirjan tectonic zone. In the Hamadan area, consisting mainly of Mesozoic plutonic and metamorphic rocks, aplites and pegmatites locally contain garnets.(Baharifar et al., 2004, Amidi and Majidi, 1977; Torkian, 1995. Garnet-bearing schists and hornfelses in the area are products of regional metamorphism shown by slate and phyllite (Baharifar, 2004. In this investigation the distribution of elements in garnet in different rock type was studied to determine their mineral types and conditions of formation. Garnet samples from igneous and metamorphic rocks were analyzed by electron microprobe (EMPA, the results of which are presented in this article. Materials and methods Thirty-five samples were selected for thin section preparation and twenty thin-polished sections were prepared for mineralogical and microprobe analysis. Thin sections of garnet-bearing igneous (pegmatite and metamorphic rocks (schist and hornfels were studied by polarizing microscope. Chemical analysis was performed on the garnets (38 points using a Caimeca SX100 electron microprobe at an acceleration voltage of 15 kV and electric current of 15 nA in the Mineral Processing Research Center, Iran. Separation of iron (II and Fe (III was calculated by Droop’s method (1987 and the structural formulas of the garnets were calculated using 24 oxygens to determine the relative proportions of the end-members using the mineral spreadsheet software of Preston and Still (2001. Results Based on the analyses, almandine (Fe - Al garnet and spessartine (Mn - Al garnet are the principal types of the (Kamari metamorphic and (Abaro pegmatitic garnets, that belong to the well-known pyralspite garnet group. Chemical zoning patterns of the garnets in the metamorphic rocks (schists differ from those in the igneous rocks (pegmatite, showing different compositions from core to rim. Petrographic evidence such as: co

  12. Geology and stratigraphy of the Challis Volcanic Group and related rocks, Little Wood River area, south-central Idaho

    Science.gov (United States)

    Sandford, Richard F.; Snee, Lawrence W.

    2005-01-01

    The southwestern part of the Challis volcanic field occupies the valley of the Little Wood River and its tributaries in the Hailey and Idaho Falls 1??2? quadrangles of south-central Idaho. The Little Wood River area is a structurally controlled topographic basin that is partly filled by Eocene Challis Volcanic Group and younger rocks. Rock types in the Challis Volcanic Group of the Little Wood River area include, in order of decreasing abundance, andesite lava flows and tuff breccia, dacite lava flows and flow breccia, volcaniclastic sedimentary rocks, lithic tuff, nonvolcanic conglomerate, and rhyolite dikes. A basal nonvolcanic conglomerate, that locally rests on upper Paleozoic sedimentary rocks at a regional unconformity, was deposited prior to eruption of volcanic rocks. Andesite was the first volcanic rock erupted and is a voluminous sequence as thick as 3,000 ft (1,000 m). Locally thick volcaniclastic sedimentary rocks accumulated in topographic lows. A sharp transition marks the beginning of dacite eruption from fissures and flow-dome complexes. Dacite flows and breccias are as thick as 2,000 ft (600 m). An upper volcaniclastic unit was deposited in paleotopographic lows following emplacement of the main dacite unit. Next, a widespread, distinctive, lithic rich ash flow tuff, correlated with the tuff of Stoddard Gulch, was deposited over much of the area. Deposition of the tuff was followed by eruption of thin andesite and dacite lava flows and deposition of conglomeratic sedimentary rocks. The entire sequence was then intruded by a dacite flow-dome complex composed of at least three separate intrusions. The Challis Volcanic Group in the study area is calcalkaline. Andesitic rocks are typically high potassium basaltic andesite, high potassium andesite, shoshonite, and banakite (latite). Dacitic rocks are high potassium dacite and trachyte. Tuffs and vitrophyres range in composition from basaltic andesite to trachyte. The paleotopographic basin in which the

  13. Basic-ultrabasic and volcanic rocks in Chagbu-Shuanghu area of northern Xizang (Tibet),China

    Institute of Scientific and Technical Information of China (English)

    邓万明; 尹集祥; 呙中平

    1996-01-01

    The widespread Early Permian and Triassic sequences outcropping in the Chagbu-Shuanghu area of northern Xizang, China, are mainly characterized by volcanic rocks belonging to tholeiite with subordinate veins of diallagite. wehrlite and limburgites schlierens. These ultrabasic rocks do not carry plastic deformational fabrics from upper mantle and may result from the crystallization of fused mass derived from mantle under condition of deeper crust or earlier segregation of tholeiitic magma. These volcanic rocks, as interlayers or lens, are generally involved in slates, limestones and pebbly slates or breccia and geochemically different from MORB. It is reasonable to conclude from research results that the volcanic activities during the Early Permian and Late Triassic would be able to occur in an intraplale environment suffering initial extension of continental crust or an aulacogen. Therefore, these basic-ultrabasic and volcanic rocks did not constitute an ophiolitic association with an occurrence 6f the

  14. An automated methodology for differentiating rock from snow, clouds and sea in Antarctica from Landsat 8 imagery: a new rock outcrop map and area estimation for the entire Antarctic continent

    Science.gov (United States)

    Burton-Johnson, Alex; Black, Martin; Fretwell, Peter T.; Kaluza-Gilbert, Joseph

    2016-08-01

    As the accuracy and sensitivity of remote-sensing satellites improve, there is an increasing demand for more accurate and updated base datasets for surveying and monitoring. However, differentiating rock outcrop from snow and ice is a particular problem in Antarctica, where extensive cloud cover and widespread shaded regions lead to classification errors. The existing rock outcrop dataset has significant georeferencing issues as well as overestimation and generalisation of rock exposure areas. The most commonly used method for automated rock and snow differentiation, the normalised difference snow index (NDSI), has difficulty differentiating rock and snow in Antarctica due to misclassification of shaded pixels and is not able to differentiate illuminated rock from clouds. This study presents a new method for identifying rock exposures using Landsat 8 data. This is the first automated methodology for snow and rock differentiation that excludes areas of snow (both illuminated and shaded), clouds and liquid water whilst identifying both sunlit and shaded rock, achieving higher and more consistent accuracies than alternative data and methods such as the NDSI. The new methodology has been applied to the whole Antarctic continent (north of 82°40' S) using Landsat 8 data to produce a new rock outcrop dataset for Antarctica. The new data (merged with existing data where Landsat 8 tiles are unavailable; most extensively south of 82°40' S) reveal that exposed rock forms 0.18 % (21 745 km2) of the total land area of Antarctica: half of previous estimates.

  15. Petrogenesis of the Mesozoic intrusive rocks in the Tongling area, Anhui Province, China and their constraint on geodynamic process

    Institute of Scientific and Technical Information of China (English)

    王强; 许继峰; 赵振华; 熊小林; 包志伟

    2003-01-01

    Petrology, element and isotopic geochemistry of the Mesozoic intrusive rocks in the Tongling area were systematically investigated in this study. The intrusive rocks can be divided into two groups, one contains shoshonitic rocks with SiO2≤55%, the other consists mainly of high-potassic calc-alkaline rocks with SiO2>55%. The shoshonitic rocks (SiO2≤55%) were generated by the fractional crystallization of the primary basaltic magma sourced from an enriched mantle, then the evolved basaltic magma likely experienced low-degree contamination with the lower crust materials when they ascended. On the other hand, although the intrusive rocks with SiO2>55% show most elemental geochemical characteristics similar to an adakite, such as high Na2O, Al2O3, Sr contents, high Sr/Y and La/Yb ratios, they have isotopic compositions much different from an adakite, such as low εNd(t) (-9.16-16.55) and high (87Sr/86Sr)i(0.7068-0.7105), and some of them show relatively high Y and Yb contents than those of an adakite. We propose that the intrusive rocks with SiO2>55% were most probably produced by mixing of the mantle-derived basaltic magma and adakite-like magma derived from the melting of basaltic lower crust that was heated by the underplating mantle-derived shoshonitic magmas. The delamination of lower crust likely took place after or during the formation of these adakite-like rocks in the Tongling area.

  16. Surficial geologic map of the Red Rock Lakes area, southwest Montana

    Science.gov (United States)

    Pierce, Kenneth L.; Chesley-Preston, Tara L.; Sojda, Richard L.

    2014-01-01

    The Centennial Valley and Centennial Range continue to be formed by ongoing displacement on the Centennial fault. The dominant fault movement is downward, creating space in the valley for lakes and the deposition of sediment. The Centennial Valley originally drained to the northeast through a canyon now represented by a chain of lakes starting with Elk Lake. Subsequently, large landslides blocked and dammed the drainage, which created Lake Centennial, in the Centennial Valley. Sediments deposited in this late Pleistocene lake underlie much of the valley floor and rest on permeable sand and gravel deposited when the valley drained to the northeast. Cold Pleistocene climates enhanced colluvial supply of gravelly sediment to mountain streams and high peak flows carried gravelly sediment into the valley. There, the lower gradient of the streams resulted in deposition of alluvial fans peripheral to Lake Centennial as the lake lowered through time to the level of the two present lakes. Pleistocene glaciers formed in the high Centennial Range, built glacial moraines, and also supplied glacial outwash to the alluvial fans. Winds from the west and south blew sand to the northeast side of the valley building up high dunes. The central part of the map area is flat, sloping to the west by only 0.6 meters in 13 kilometers (2 feet in 8 miles) to form a watery lowland. This lowland contains Upper and Lower Red Rock Lakes, many ponds, and peat lands inside the “water plane,” above which are somewhat steeper slopes. The permeable sands and gravels beneath Lake Centennial sediments provide a path for groundwater recharged from the adjacent uplands. This groundwater leaks upward through Lake Centennial sediments and sustains wetland vegetation into late summer. Upper and Lower Red Rock Lakes are formed by alluvial-fan dams. Alluvial fans converge from both the south and the north to form outlet thresholds that dam the two shallow lakes upstream. The surficial geology aids in

  17. COMPOSITIONAL AND PETROGENETIC FEATURES OF SCHISTOSE ROCKS OF IBADAN AREA, SOUTHWESTERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Oluwatoke O.O.

    2009-12-01

    Full Text Available Amphibole and quartz schist which occur in association with migmatite gneiss, granitic gneiss and Pan African Older Granitebodies around Ibadan area, southwestern Nigeria, were studied with a view to elucidate their compositional characteristics andtheir evolution.Mineralogical determinations from optical studies show a high proportion of granular quartz and accessory muscovite in thequartz schist. The amphibole schist on the other hand comprises mainly dark colored bands of hornblende with subordinate tremolite, chlorite and minor amounts of plagioclase and quartz. 
    Chemical analysis of the samples obtained by Inductively Coupled Plasma Mass Spectrometry (ICPMS instrumentation method, involving major and trace elements reveal the silicieous nature of the quartz schist and and the amphibole .samples of both rock units are also marked by relatively elevated contents of Ba, Zr, Rb, La and Ce and Zr. In addition, variation plots using Na2O, Al2O,K2Osuggests arenaceous sedimentary ancestry for the quartz schist and an igneous ancestry most probablymafic extrusive volcanics for the amphibole schist. Provenance indicators, such as Ba, in the quartz schists suggest derivation of this sedimentary protolith from the weathering of largely granitic rocks. Similarity of the amphibole schist progenitors with subalkaline basaltic andesite is also implied by the Na2O+K2O versus SiO2 bivariate plot, whilethe Na2O+K2O-Fe2O3 (t-MgO ternary plot reveal their calc-alkaline affinity. Tectonically, the quartz schists evolved within the passive margin environment, whereas the MgO-Fe2O3-Al2O3 ternary plots reveal an Ocean island basalt tectonic evolution for the amphibole schist.

  18. The distribution of the oil derived from Cambrian source rocks in Lunnan area, the Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    There are great differences in biomarks between Cambrian oil and Middle-Upper Ordoviclan oil. In this stuty, the authors analyzed 40 oils found in Lunnan area by GC-MS and calculated the content of Cambrian oil in the 40 oils according to the steroid indexes of typical oil mixture and match experiment. The results show that it is a general phenomenon in Ordovician reservoir that the oil derived from Cambrian source rock mixed with the oil derived from Middle-Upper Ordovician source rock in Lunnan area, the mixture degree of the two oils is lower in Carboniferous reservoir than in Ordovician reservoir, and the oils kept in Triassic reservoir have single source, Middle-Upper Ordovician source rock. The mixture oils mainly composed of Cambrian oil (>50%) distributed in Sangtamu fault zone, and the oils found in Lunnan fault zone are Middle-Upper Ordovician oil. This distribution of oils in Lunnan area is owing to that Lunnan fault zone is located in anticline axis part, Lunnan fault zone underwent serious erosion, and the oils from Cambrian source rock accumulated in Lunnan fault zone were degraded completely during Caledonian-Hercynian movement. But the Cambrian oil accumulated in Sangtamu fault zone was not degraded completely and some of them were left for the location of Sangtamu fault zone is lower than Lunnan fault zone. Later, the oil derived from Middle-Upper Ordovician source rock mixed with the remained Cambrian oil, and the mixture oil formed in Sangtamu fault zone.

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

    Indian Academy of Sciences (India)

    A Krishnakanta Singh; G Vallinayagam

    2004-12-01

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

  20. Neogene seismites and seismic volcanic rocks in the Linqu area, Shandong Province, E China

    Directory of Open Access Journals (Sweden)

    Tian H.S.

    2014-07-01

    Full Text Available The Yishu Fault Zone runs through the centre of Shandong Province (E China; it is a deep-seated large fault system that still is active. Two volcanic faulted basins (the Shanwang and Linqu Basins in the Linqu area, west of the fault zone, are exposed to rifting, which process is accompanied by a series of tectonic and volcanic earthquakes with a magnitude of 5-8. Lacustrine sediments in the basins were affected by these earthquakes so that seismites with a variety of soft-sediment deformation structures originated. The seismites form part of the Shanwang Formation of the Linqu Group. Semi-consolidated fluvial conglomerates became deformed in a brittle way; these seismites are present at the base of the Yaoshan Formation. Intense earthquakes triggered by volcanic activity left their traces in the form of seismic volcanic rocks associated with liquefied-sand veins in the basalt/sand intercalations at the base of the Yaoshan Formation. These palaeo-earthquake records are dated around 14-10 Ma; they are responses to the intense tectonic extension and the basin rifting in this area and even the activity of the Yishu Fault Zone in the Himalayan tectonic cycle.

  1. Case Study of Volcanic Rock Reservoir--Beibao Area of Nanbao Sag

    Institute of Scientific and Technical Information of China (English)

    Guo Qijun; Wan Zhimin; Jiao Shouquan; Liu Laixiang

    1997-01-01

    @@ Preface Crude has been produced from volcanic rock reservoirs inAmerica, Libya, Indonesia and Japan, according to the available data. Oil and gas Production from volcanic rock reservoirs in Japan accounts for 30% of the total, with the recoverable reserves estimated at 48% of the total. Oil and gas traps of volcanic rock reservoir with better reservoir properties and flow potential have been discovered in Liaohe, Erlian, Jizhong, Huanghua, Jiyang, Linqing,Jiangsu and Xinjiang of China since the 1970's. However,the systematic study of volcanic rock reservoir is just in the beginning.

  2. An Experimental Study of Mixture Corrosion Effects of Carbonate Rocks in the Transitional Zone of Littoral Karst Areas

    Institute of Scientific and Technical Information of China (English)

    陈鸿汉; 邹胜章; 朱远峰; 陈从喜

    2001-01-01

    The mechanism for development of littoral karst differs from that of inland karst, and the mixture corrosion effects are one of the most important factors that control the development of littoral karst. Through seven groups of static experiments carried out in a closed CO2-H2O system, basic conclusions can be drawn as follows: (1) the basic law of corrosion process in a transitional zone of seawater-freshwater in littoral karst areas is identical with that in the fresh water,i.e., the lithologic characteristics and rock structure are the main factors which control the development of littoral karst; (2)the mixture corrosion rate of the carbonate rock in the above transitional zone is faster than that in fresh water or seawater;(3) the mechanism for development of carbonate rocks differs at various pressures of CO2 in a transitional zone in littoral karst areas.``

  3. Mineral chemical compositions of late Cretaceous volcanic rocks in the Giresun area, NE Turkey: Implications for the crystallization conditions

    Science.gov (United States)

    Oǧuz, Simge; Aydin, Faruk; Uysal, İbrahim; Şen, Cüneyt

    2016-04-01

    This contribution contains phenocryst assemblages and mineral chemical data of late Cretaceous volcanic (LCV) rocks from the south of Görele and Tirebolu areas (Giresun, NE Turkey) in order to investigate their crystallization conditions. The LCV rocks in the study area occur in two different periods (Coniasiyen-Early Santonian and Early-Middle Campanian), which generally consist of alternation of mafic-intermediate (basaltic to andesitic) and felsic rock series (dacitic and rhyolitic) within each period. The basaltic and andesitic rocks in both periods generally exhibit porphyritic to hyalo-microlitic porphyritic texture, and contain phenocrysts of plagioclase and pyroxene, whereas the dacitic and rhyolitic rocks of the volcanic sequence usually show a vitrophyric texture with predominant plagioclase, K-feldspar, quartz and lesser amphibole-biotite phenocrysts. Zoned plagioclase crystals of the mafic and felsic rocks in different volcanic periods are basically different in composition. The compositions of plagioclase in the first-stage mafic rocks range from An52 to An78 whereas those of plagioclase from the first-stage felsic rocks have lower An content varying from An38 to An50. Rim to core profile for the zoned plagioclase of the first-stage mafic rocks show quite abrupt and notable compositional variations whereas that of the first-stage felsic rocks show slight compositional variation, although some of the grains may display reverse zoning. On the other hand, although no zoned plagioclase phenocryst observed in the second-stage mafic rocks, the compositions of microlitic plagioclase show wide range of compositional variation (An45-80). The compositions of zoned plagioclase in the second-stage felsic rocks are more calcic (An65-81) than those of the first-stage felsic rocks, and their rim to core profile display considerable oscillatory zoning. The compositions of pyroxenes in the first- and second-stage mafic-intermediate rocks vary over a wide range from

  4. Factor analysis of rock, soil and water geochemical data from Salem magnesite mines and surrounding area, Salem, southern India

    Science.gov (United States)

    Satyanarayanan, M.; Eswaramoorthi, S.; Subramanian, S.; Periakali, P.

    2017-09-01

    Geochemical analytical data of 15 representative rock samples, 34 soil samples and 55 groundwater samples collected from Salem magnesite mines and surrounding area in Salem, southern India, were subjected to R-mode factor analysis. A maximum of three factors account for 93.8 % variance in rock data, six factors for 84 % variance in soil data, five factors for 71.2 % in groundwater data during summer and six factors for 73.7 % during winter. Total dissolved solids are predominantly contributed by Mg, Na, Cl and SO4 ions in both seasons and are derived from the country rock and mining waste by dissolution of minerals like magnesite, gypsum, halite. The results also show that groundwater is enriched in considerable amount of minor and trace elements (Fe, Mn, Ni, Cr and Co). Nickel, chromium and cobalt in groundwater and soil are derived from leaching of huge mine dumps deposited by selective magnesite mining activity. The factor analysis on trivalent, hexavalent and total Cr in groundwater indicates that most of the Cr in summer is trivalent and in winter hexavalent. The gradational decrease in topographical elevation from northern mine area to the southern residential area, combined regional hydrogeological factors and distribution of ultramafic rocks in the northern part of the study area indicate that these toxic trace elements in water were derived from mine dumps.

  5. Factor analysis of rock, soil and water geochemical data from Salem magnesite mines and surrounding area, Salem, southern India

    Science.gov (United States)

    Satyanarayanan, M.; Eswaramoorthi, S.; Subramanian, S.; Periakali, P.

    2016-04-01

    Geochemical analytical data of 15 representative rock samples, 34 soil samples and 55 groundwater samples collected from Salem magnesite mines and surrounding area in Salem, southern India, were subjected to R-mode factor analysis. A maximum of three factors account for 93.8 % variance in rock data, six factors for 84 % variance in soil data, five factors for 71.2 % in groundwater data during summer and six factors for 73.7 % during winter. Total dissolved solids are predominantly contributed by Mg, Na, Cl and SO4 ions in both seasons and are derived from the country rock and mining waste by dissolution of minerals like magnesite, gypsum, halite. The results also show that groundwater is enriched in considerable amount of minor and trace elements (Fe, Mn, Ni, Cr and Co). Nickel, chromium and cobalt in groundwater and soil are derived from leaching of huge mine dumps deposited by selective magnesite mining activity. The factor analysis on trivalent, hexavalent and total Cr in groundwater indicates that most of the Cr in summer is trivalent and in winter hexavalent. The gradational decrease in topographical elevation from northern mine area to the southern residential area, combined regional hydrogeological factors and distribution of ultramafic rocks in the northern part of the study area indicate that these toxic trace elements in water were derived from mine dumps.

  6. A Preliminary Study on Paleomagnetism and Rock Magnetism of Eclogite from the Maobei Area

    Institute of Scientific and Technical Information of China (English)

    Meng Xiaohong; Yu Qinfan; GuoYouzhao; Zhou Yaoxiu

    2007-01-01

    A preliminary study of paleomagnetism and rock magnetism has been done on 55 eclogite samples collected from the Chinese Continental Scientific Drilling (CCSD) site at the Maobei (毛北) area,Donghai (东海) County, Jiangsu (江苏) Province. Also the isothermal remanence, hysteresis loop, magnetic fabric, thermal susceptibility were measured, and analyses were made by electron-probe and scanning electric microscope on some samples synchronously. The result indicates that there are two groups of stable remanence, the normal and reversed magnetization. The remanence orientations are: D=94.3°, I=-29.1° and D=273.7°, I=15.4°, respectively. The magnetization intensity and the density of the samples which carry the normal magnetization are very different from those bearing reversed magnetization. The magnetic anisotropy is weak, and the minimum axis is hardly determined. The isothermal remanence and the hysteresis loop show that the magnetic carriers of the eclogite are likely SD (single domain) and PSD(pseudo-single domain) magnetite. According to the magnetic property, the cause of formation of magnetic carriers, the mechanism of the remanence, and the significance for the tectonics are discussed.

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

    Science.gov (United States)

    Krishnakanta Singh, A.; Vallinayagam, G.

    2004-12-01

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

  8. Alteration processes in igneous rocks of the michilla mining area, coastal range, northern chile, and their relation with copper mineralisation

    Science.gov (United States)

    Oliveros, V.; Aguirre, L.; Townley, B.

    2003-04-01

    A 10 km thick homoclinal sequence of intermediate volcanic and sedimentary Jurassic rocks crops out in the Michilla mining area, Coastal Range, northern Chile (22-22°45S, 70-70°15W). Cretaceous plutons, intermediate to acid in composition, intrude this sequence together with numerous small basic to acid dykes and stocks. Main deposits are stratabound Cu-(Ag) with the ore minerals emplaced at the porous tops of the volcanic flows. However, some discordant orebodies, e.g. hydrothermal breccias, exist within the manto-type deposits. The volcanic sequence, and a minor part of the plutonic rocks, have been affected by three different alteration processes, each of them with their distinct mineral assemblages reflecting that every process was developed under different physicochemical conditions. The volcanic rocks far from the mining area are affected by a regional scale alteration process, basically isochemical. Its products are typical of a low-grade event: chl + ep +qtz + ttn (+- ab +- cal) with no ore minerals associated. The temperature interval, estimated by the chlorite geothermometer, ranges between 250 and 350°C. This alteration is either due to very low grade burial metamorphism or to hydrothermalism related to the Late Jurassic - Cretaceous plutonism. Inside the mining district the volcanic rocks are affected by a local scale alteration process originated by the intrusion of small stocks and dykes. This event is characterized by strong sodic metasomatism and minor Mg mobility. Two stages probably occurred as suggested by the two main mineral assemblages present, a propylitic (ab + ep + chl + act + ttn + qtz) and a quartz-sericitic one (ab + ser + qtz + tnn). They would reflect the changes in temperature, water/rock ratio and pH conditions during the whole process. Ore minerals related to this alteration are chalcopyrite, chalcocite and minor bornite and native silver. A temperature interval of 200-300°C is indicated by the chlorite geothermometer for the

  9. Microseismic Precursory Characteristics of Rock Burst Hazard in Mining Areas Near a Large Residual Coal Pillar: A Case Study from Xuzhuang Coal Mine, Xuzhou, China

    Science.gov (United States)

    Cao, An-ye; Dou, Lin-ming; Wang, Chang-bin; Yao, Xiao-xiao; Dong, Jing-yuan; Gu, Yu

    2016-11-01

    Identification of precursory characteristics is a key issue for rock burst prevention. The aim of this research is to provide a reference for assessing rock burst risk and determining potential rock burst risk areas in coal mining. In this work, the microseismic multidimensional information for the identification of rock bursts and spatial-temporal pre-warning was investigated in a specific coalface which suffered high rock burst risk in a mining area near a large residual coal pillar. Firstly, microseismicity evolution prior to a disastrous rock burst was qualitatively analysed, and the abnormal clustering of seismic sources, abnormal variations in daily total energy release, and event counts can be regarded as precursors to rock burst. Secondly, passive tomographic imaging has been used to locate high seismic activity zones and assess rock burst hazard when the coalface passes through residual pillar areas. The results show that high-velocity or velocity anomaly regions correlated well with strong seismic activities in future mining periods and that passive tomography has the potential to describe, both quantitatively and periodically, hazardous regions and assess rock burst risk. Finally, the bursting strain energy index was further used for short-term spatial-temporal pre-warning of rock bursts. The temporal sequence curve and spatial contour nephograms indicate that the status of the danger and the specific hazardous zones, and levels of rock burst risk can be quantitatively and rapidly analysed in short time and in space. The multidimensional precursory characteristic identification of rock bursts, including qualitative analysis, intermediate and short-time quantitative predictions, can guide the choice of measures implemented to control rock bursts in the field, and provides a new approach to monitor and forecast rock bursts in space and time.

  10. Numerical Analysis of Finite Deformation of Overbroken Rock Mass in Gob Area Based on Euler Model of Control Volume

    Institute of Scientific and Technical Information of China (English)

    LIU Wei-qun; MIAO Xie-xing

    2006-01-01

    The overbroken rock mass of gob areas is made up of broken and accumulated rock blocks compressed to some extent by the overlying strata. The bearing pressure of the gob can directly affect the safety of mining fields, formation of road retained along the next goaf and seepage of water and methane through the gob. In this paper, the software RFPA'2000 is used to construct numerical models. Especially the Euler method of control volume is proposed to solve the simulation difficulty arising from plastically finite deformations. The results show that three characteristic regions occurred in the gob area: (1) a naturally accumulated region, 0-10 m away from unbroken surrounding rock walls, where the bearing pressure is nearly zero; (2) an overcompacted region, 10-20 m away from unbroken walls, where the bearing pressure results in the maximum value of the gob area; (3) a stable compaction region, more than 20 m away from unbroken walls and occupying absolutely most of the gob area, where the bearing pressures show basically no differences. Such a characteristic can explain the easy-seepaged "O"-ring phenomena around mining fields very well.

  11. Zircon SHRIMP age of Mesoarchaean meta-argillo-arenaceous rock in the Anshan area and its geological significance

    Institute of Scientific and Technical Information of China (English)

    WAN; Yusheng(万渝生); SONG; Biao(宋彪); LIU; Dunyi(刘敦一)

    2002-01-01

    In order to better understand the early continental evolution of the Anshan area, one of the typical Precambrian distribution areas of the North China Craton, the geochronology and REE composition of the zircons from the meta-argillo-arenaceous rock occurred as enclave in 3.1 Ga Lishan trondhjemite are studied by using SHRIMP II ion microprobe. It is indicated that the Paleoarchaean is a very important continental formation period in the Anshan area and 3.2 Ga can be regarded as the boundary between the Paleoarchaean and Mesoarchaean.

  12. Supracrustal rocks in the Kuovila area, Southern Finland: structural evolution, geochemical characteristics and the age of volcanism

    Directory of Open Access Journals (Sweden)

    Pietari Skyttä

    2005-01-01

    Full Text Available The supracrustal rocks of the Kuovila area in the Palaeoproterozoic Svecofennian Uusimaa Belt, southern Finland, consist mainly of volcaniclastic rocks associated with banded iron formations (BIFs and marbles. Small ZnS and PbS mineralizations are occasionally located within the marbles. Some primary features are well preserved in the sedimentary and volcanic rocks, including lamination in tuffites and banded iron formations. Geochemical results show that the volcanism was bimodal and it mainly had volcanic arc affinity. Specific geochemical indicators suggesting a volcanic arc origin for the Kuovila volcanic rocks include: 1 Enrichment of LILE over the HFSE elements and 2 Distinctly low Nb and Ta contents in relation to Th, Ce and LREE. Geochemistry of the Kuovila area volcanic rocks is very similar to those of the Orijärvi and Kisko formations, located ~15 km NE of Kuovila. Felsic tuff in the Kuovila area was dated at 1891±4 Ma by the U-Pb system on zircons. Consequently volcanism was contemporaneous with magmatism in the adjacent Orijärvi area, thus representing the earliest identified volcanic stage in the southern Svecofennian Uusimaa Belt. Early deformation structures within the Kuovila area are suggested to relate to low-metamorphic or localized low-angle thrusting during D1. F1 folds were recumbent and the S1 cleavages are generally weak. Thrusting was followed by approximately N–S contraction with upright, peak-metamorphic F2 folding overprinting D1 structures and defining the Kuovila synform. Two separate intrusive phases include a synvolcanic granodiorite-diorite-gabbro association and a weakly S2-foliated syn-D2 granodiorite. Anatectic granites and associated migmatizing veins are absent, therefore suggesting that D2 pre-dates the ~1.84–1.82 Ga metamorphic event in the Southern Svecofennian Arc Complex (SSAC. D2 structuresin the Kuovila area are suggested to correlate with the early structures with associated axial planar

  13. Mesozoic adakitic rocks from the Xuzhou-Suzhou area, eastern China: Evidence for partial melting of delaminated lower continental crust

    Science.gov (United States)

    Xu, Wen-Liang; Wang, Qing-Hai; Wang, Dong-Yan; Guo, Jing-Hui; Pei, Fu-Ping

    2006-09-01

    Adakitic rocks in the Xuzhou-Suzhou area, eastern China, consist of dioritic and monzodioritic porphyries and were dated at 131-132 Ma by the SHRIMP U-Pb zircon method. These rocks have high MgO content (1.47-5.73%), high Mg # values (0.49-0.61), and high La/Yb and Sr/Y ratios. These features are similar to rocks derived from partial melting of a subducted oceanic slab. However, their high initial 87Sr/ 86Sr (0.7053-0.7075) and low ɛNd( t) values (-4.43˜-13.14) are inconsistent with the origin from slab melting. These rocks often contain garnet residual crystals and eclogite, garnet clinopyroxenite, and garnet amphibolite xenoliths. Petrographical characteristics and estimated P- T conditions of these xenoliths indicate that they were once deeply subducted and subsequently underwent rapid exhumation in the early Mesozoic. Garnet residual crystals from the porphyries show similar chemical compositions to garnets from garnet clinopyroxenite and garnet amphibolite xenoliths. Ages of the inherited zircons of the xenoliths and their host rocks likely indicate that sources for the adakitic magma and protoliths of the eclogite and garnet clinopyroxenite xenoliths in the study area were from Precambrian basement of the North China Craton. The data also suggest that the lower continental crust in the eastern North China Craton was thickened during the early Mesozoic and delaminated in the early Cretaceous. The high-Mg adakitic magma resulted from partial melting of this delaminated lower continental crust and its subsequent interaction with the mantle during upward transport, leaving garnet as the residual phase.

  14. Mesozoic adakitic rocks from the Xuzhou Suzhou area, eastern China: Evidence for partial melting of delaminated lower continental crust

    Science.gov (United States)

    Xu, Wen-Liang; Wang, Qing-Hai; Wang, Dong-Yan; Guo, Jing-Hui; Pei, Fu-Ping

    2006-07-01

    Adakitic rocks in the Xuzhou-Suzhou area, eastern China, consist of dioritic and monzodioritic porphyries and were dated at 131-132 Ma by the SHRIMP U-Pb zircon method. These rocks have high MgO content (1.47-5.73%), high Mg # values (0.49-0.61), and high La/Yb and Sr/Y ratios. These features are similar to rocks derived from partial melting of a subducted oceanic slab. However, their high initial 87Sr/ 86Sr (0.7053-0.7075) and low ɛNd( t) values (-4.43 to -13.14) are inconsistent with the origin from slab melting. These rocks often contain garnet residual crystals and eclogite, garnet clinopyroxenite, and garnet amphibolite xenoliths. Petrographical characteristics and estimated P-T conditions of these xenoliths indicate that they were once deeply subducted and subsequently underwent rapid exhumation in the early Mesozoic. Garnet residual crystals from the porphyries show similar chemical compositions to garnets from garnet clinopyroxenite and garnet amphibolite xenoliths. Ages of the inherited zircons of the xenoliths and their host rocks likely indicate that sources for the adakitic magma and protoliths of the eclogite and garnet clinopyroxenite xenoliths in the study area were from Precambrian basement of the North China Craton. The data also suggest that the lower continental crust in the eastern North China Craton was thickened during the early Mesozoic and delaminated in the early Cretaceous. The high-Mg adakitic magma resulted from partial melting of this delaminated lower continental crust and its subsequent interaction with the mantle during upward transport, leaving garnet as the residual phase.

  15. Volcanostratigraphy, petrography and petrochemistry of Late Cretaceous volcanic rocks from the Görele area (Giresun, NE Turkey)

    Science.gov (United States)

    Oguz, Simge; Aydin, Faruk; Baser, Rasim

    2015-04-01

    In this study, we have reported for lithological, petrographical and geochemical features of late Cretaceous volcanic rocks from the Çanakçı and the Karabörk areas in the south-eastern part of Görele (Giresun, NE Turkey) in order to investigate their origin and magmatic evolution. Based on the previous ages and recent volcano-stratigraphic studies, the late Cretaceous time in the study area is characterized by an intensive volcanic activity that occurred in two different periods. The first period of the late Cretaceous volcanism (Cenomanian-Santonian; 100-85 My), conformably overlain by Upper Jurassic-Lower Cretaceous massive carbonates (Berdiga Formation), is represented by bimodal units consisting of mainly mafic rock series (basaltic-andesitic lavas and hyaloclastites, dikes and sills) in the lower part (Çatak Formation), and felsic rock series (dacitic lavas and hyaloclastites, crystal- and pyrite-bearing tuffs) in the upper part (Kızılkaya Formation). The second period of the late Cretaceous volcanism (Santonian-Late Campanian; 85-75 Ma) is also represented by bimodal character and again begins with mafic rock suites (basaltic-basaltic andesitic lavas and hyaloclastites) in the lower part (Çağlayan Formation), and grades upward into felsic rock suites (biotite-bearing rhyolitic lavas, ignimbrites and hyaloclastites) through the upper part (Tirebolu Formation). These bimodal units are intercalated with volcanic conglomerates-sandstones, claystones, marl and red pelagic limestones throughout the volcanic sequence, and the felsic rock series have a special important due to hosting of volcanogenic massive sulfide deposits in the region. All volcano-sedimentary units are covered by Tonya Formation (Late Campanian-Paleocene) containing calciturbidites, biomicrites and clayey limestones. The mafic rocks in the two volcanic periods generally include basalt, basaltic andesite and minor andesite, whereas felsic volcanics of the first period mainly consists of

  16. Tapeworms of rock dove and domestic chicken in Taif area, Saudi Arabia.

    Science.gov (United States)

    Zahrani, Mohammad R; Ashour, Ameen A; Shobrak, M Y

    2012-12-01

    The present study aimed to identify the tapeworms that parasitize the rock dove Columba livia palastinae and domestic chicken Gallus gallus domesticus in Taif governorate, Saudi Arabia. A total of 115 rock doves and 105 domestic chicken have been examined. Birds were brought in from the wells and farms inside and outside the city of Taif. In rock doves, the percentage of infection was recorded as Cotugnia digonopora 5.21%, Hymenolepis carioca 10.43%, Raillietina echinobothrida 27.82%, Raillietina tetragona 22.6%. The prevalence of infection recorded in Municipal chicken with different types of tapeworms was Cotugnia digonopora 7.61%, Choanotaenia infundibulum 12.38%, Amoebotaenia sphenoides 7.61%, Raillietina echinobothrida 11.42%, Raillietina tetragona 8.57%, Raillietina (Paroniella) kashiwarensis 4.76%. The overall percentage of infected rock pigeons Columba livia palastinae with tapeworms was 66.1% while the percentage of infected chicken Gallus gallus domestica was 52.3%. The study defined and described this species as classification keys in place.

  17. Basic investigation and analysis for preferred host rocks and natural analogue study area with reference to high level radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeong Ryul; Park, J. K.; Hwang, D. H.; Lee, J. H.; Yun, H. S.; Kim, D. Y.; Park, H. S.; Koo, S. B.; Cho, J. D.; Kim, K. E. [Korea Inst. of Geology, Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    The purpose of this study is basic investigation and analysis for preferred host rocks and natural analogue study area to develope underground disposal technique of high level radioactive waste in future. The study has been done for the crystalline rocks(especially granitic rocks) with emphasis of abandoned metallic mines and uranium ore deposits, and for the geological structure study by using gravity and aeromagnetic data. 138 refs., 54 tabs., 130 figs. (author)

  18. Age, petrogenesis and significance of 1 Ga granitoids and related rocks from the Sendra area, Aravalli Craton, NW India

    Science.gov (United States)

    Pandit, M. K.; Carter, L. M.; Ashwal, L. D.; Tucker, R. D.; Torsvik, T. H.; Jamtveit, B.; Bhushan, S. K.

    2003-12-01

    We present new geochronological, petrological, geochemical and isotopic data for granitic and related rocks from the Aravalli Craton, Rajasthan, northwestern India. In the Sendra area, five variably deformed granitoid plutons, ranging in composition from tonalite to granite, cut across carbonate-rich metasedimentary rocks of the Delhi Supergroup. The largest of these bodies, the Chang pluton (˜15 km 2) is dominated by monzogranitic gneisses and aplitic dykes, composed of subequal proportions of quartz, plagioclase (An 7-20) and microcline (Or 92-98), with lesser biotite (Fe ∗=0.8-0.9) and accessory muscovite (Fe ∗=0.7-0.8). U-Pb zircon data (TIMS method) for a biotite granite gneiss yield a weighted mean 207Pb/ 206Pb age of 967.8±1.2 Ma, which we interpret as representing the time of magmatic crystallization. Rb-Sr whole-rock isotopic data for the Chang pluton, including new analyses as well as previously published ones, yield a regression of 906±67 Ma (MSWD=82), which is barely within error of the U-Pb age. There is evidence for open-system behaviour in the Rb-Sr system, particularly for whole-rock samples with low Sr concentrations, and consequently high Rb/Sr. Sm-Nd isotopic data fail to yield meaningful age information. Initial isotopic ratios (at 968 Ma) for Chang pluton granitoids ( ISr=0.7110±14; ɛNd=-3.28±0.47) are compatible with source materials similar to Archaean amphibolitic rocks of the Banded Gneiss Complex. Spatially associated with the Chang pluton is a massive metagabbro, composed of plagioclase (An 45-68) and magnesio-hornblende (Fe ∗=0.3-0.4), with secondary Cl-rich scapolite and ferrian zoisite. The scapolite and zoisite likely crystallized from metamorphic fluids that interacted with nearby calc-silicate schists and gneisses of the Delhi Supergroup. Aside from slight enrichments in Rb, U, Th and Ba, this metagabbro retains a primitive chemical signature similar to N-MORB (LREE depletion, low K), and initial isotopic ratios ( ISr=0

  19. Identification methods of coal-bearing source rocks for Yacheng Formation in the western deepwater area of South China Sea

    Institute of Scientific and Technical Information of China (English)

    REN Jinfeng; ZHANG Yingzhao; WANG Hua; WANG Yahui; GAN Huajun; HE Weijun; SUN Ming; SONG Guangzeng

    2015-01-01

    Owing to the fact that the coal-beds are with the characteristics of multi-beds, thin single-bed, rapid lateral changes and deep burial, coal-bearing source rocks are difficult to be identified and predicted, especially in the lower exploration deepwater area. In this paper, a new integrative process utilizing geology and geophysics is proposed for better predicting the distribution of coal-bearing source rocks. Coal-beds were identified by the logging responses of“three higher, three lower, and one expand”and carbargilite were recognized by the characteristics of“four higher and one lower”. Based on the above logical decision, coal-beds and carbargilite can be distinguished automatically by cluster analysis of logging curves in verticality. Within the constraints of well-seismic calibration, the coal-beds group also can be detected in horizontality by the integrated representation of“negative phase, higher Q, lower impedance and lower frequency”within the seismic data. However, the distribution of coal-bearing source rocks utilizing geophysical methodology may do not conform to the geological rules of coal accumulation. And then the main geological controlling factors of coal accumulation are comprehensively analyzed as follows:(1) Paleotopography and tectonic subsidence determine the planar range of terrestrial-marine transitional facies markedly;(2) The relative sea level changes affect the accommodation space and shoreline migration, and limit the vertical range of coal-beds. More specifically, the relationship between the accommodation creation rate and the peat accumulation rate is a fundamental control on coal accumulation. The thickest and most widespread coals form where those two factors reached a state of balance;(3) The supply of autochthonous clasts and the distance between deposition places and paleovegetation accumulated area are the critical factor to form abundant coal, which means that if deposition area is close to paleouplift, there

  20. Integrative method in lithofacies characteristics and 3D velocity volume of the Permian igneous rocks in H area, Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    Yang Haijun; Liu Yongfu; Xie Huiwen; Xu Yongzhong; Sun Qi; Wang Shuangshuang

    2013-01-01

    This paper introduces horizon control,seismic control,logging control and facies control methods through the application of the least squares fitting of logging curves,seismic inversion and facies-controlled techniques.Based on the microgeology and thin section analyses,the lithology,lithofacies and periods of the Permian igneous rocks are described in detail.The seismic inversion and facies-controlled techniques were used to find the distribution characteristics of the igneous rocks and the 3D velocity volume.The least squares fitting of the logging curves overcome the problem that the work area is short of density logging data.Through analysis of thin sections,the lithofacies can be classified into eruption airfall subfacies,eruption pyroclastic flow subfacies and eruption facies.

  1. Subsurface Determination Of Cavities In Limestone Rock Area By Geoelectric Method In Tinapan Village Todanan Blora District Central Java Indonesia

    Directory of Open Access Journals (Sweden)

    Agus Santoso

    2016-09-01

    Full Text Available Two Dimensional of geoelectric method can be used to find out the conductive formation in the earth surface. The purpose of this research is to give the description about the geological subsurface formation, that the high resistivity value is indicate the potential area of cave and void in the limestone rocks. The dipole dipolegeoelectric method is used in this research with the path of lines is 250 m with 10 m electrode spacing. The total lines is 7 and the azimuth is from east to west. Resistivity method is started with inject the electrical current into the earth by current electrode, then potential difference will arise and measured by potential electrode. Variation value of resistance for each layer rock can calculated by divided potential defference with current value. The existence of the cavity is known by the resistivity value is more than 2500 ohm-m, while the cracks have a resistivity of 1500 to 2500 ohm-m

  2. State of stress in the area of a shaft being excavated with rock freezing considering dependence of rock physical properties on temperature

    Energy Technology Data Exchange (ETDEWEB)

    Dobrocinski, S.; Szmelter, J.

    1978-01-01

    A shaft 4.37 m in diameter and 80 m deep was excavated with rock freezing. Thirty-one freezing pipes formed a circle with a diameter of 10.8 m. Load bearing capacity of the frozen rocks which would guarantee safety during shaft sinking was determined. The finite element method was used. Number of unknowns was reduced by solving 2 two-dimensional problems: determining temperature distribution in the vertical planes and determining temperature and stress distribution in the axial cross-cuts. On the basis of an axisymmetric numerical model of rock strata temperature distribution was determined (varying thermal conductivity of rock strata was considered). On the basis of the temperature distribution, state of stress in rock strata was assessed considering dependence of rock elastic properties on temperature.

  3. Geology and petrology of Tertiary volcanic rocks of Sarbisheh perlite mine area (eastern Iran and industrial applications

    Directory of Open Access Journals (Sweden)

    Seayad Sayid Mohammadi

    2012-04-01

    Full Text Available The study area is located at northwest of Sarbisheh in South Khorasan province and eastern border of Lut block. In this area, Tertiary (Eocene-Oligocene to Pliocene volcanic rocks consisting of basaltic andesite, dacite, rhyodacite, vitreous rhyolite (perlitic in some parts, tuff and ignimbrite are exposed. In the Daghar Mountain, A, B and C perlite layers with thicknesses of 102, 7 and 58 meters respectively, occur alternatively with volcanic-pyroclastic rocks. Zoning, sieve texture and embayment of plagioclase and roundness of minerals in the lavas indicate disequilibrium conditions during magma crystallization. Chemically, these are meta-aluminous, medium to high-K calc-alkaline, enriched in LILE and negative anomaly for Nb and Ti. Chondrite-normalized Rare Earth Elements (REE plots indicate enrichment of light REE in comparison with heavy REE, (La/YbN of 9.14-12.64, low negative anomaly for Eu in basaltic andesite (Eu/Eu*=0.91 and dacite (Eu/Eu*=0.78-0.87 and strong negative anomaly for Eu in the rhyolites (Eu/Eu*=0.18-0.35. Negative anomaly for Eu indicates calc-alkaline nature for these rocks. On the basis of chemical characteristics and magnetic susceptibility, these are I-type. Tectonically, the rocks belong to subduction zone and active continental margin and their parental magma originated from partial melting of enriched mantle and then crustal contamination during differentiation process. Dacites have an initial 87Sr/86Sr between 0.7048 and 0.7050 (average 0.7049 that confirm mantle source for the magma. Volcanic glasses of rhyolitic composition altered by hydration (likely meteoric water and formed perlite. Physical tests and chemical analyses show that perlite of Sarbisheh is suitable as raw material for production of expanded perlite.

  4. Nd Isotopic Composition and Material Source of Pre—and Post—Sinian Sedimentary Rocks in Xiushui Area,Jiangxi Province

    Institute of Scientific and Technical Information of China (English)

    沈谓洲; 刘继顺; 等

    1992-01-01

    Reported in this paper are the Nd isotopic compositions of the pre-Sinian and Sinian-Cambrian sedimentary rocks in the Xiushui area,Jiangxi Province.Significant differences are noticed between them in their Nd isotopic dompositions.As for the pre-Sinian lightly metmorphozed sedimentary rocks,143Nd/144Nd=0.512000-0.512214,CNd(T)=-8.04-9.99,and TDM=18332426Ma are suggested for the Sinian-Cambrian sedimentary rocks .These differences would reflect the diversity of material source for the sedimentary rocks deposited before and after the Sinian period.Mantle material ap-pears to have been involved in the formation of the pre-Sinian sedimentary rocks while the post-Sinian sedimentary rocks are composed mainly of recycled detritus from the continental crust.

  5. The Metamorphic Rocks-Hosted Gold Mineralization At Rumbia Mountains Prospect Area In The Southeastern Arm of Sulawesi Island, Indonesia

    Directory of Open Access Journals (Sweden)

    Hasria Hasria

    2017-09-01

    Full Text Available Recently, in Indonesia gold exploration activities  are not only focused along volcanic-magmatic belts, but also starting to shift along metamorphic and sedimentary terrains. The study area is located in Rumbia mountains, Bombana Regency, Southeast Sulawesi Province. This paper is aimed to describe characteristics of alteration and ore mineralization associated  with metamorphic rock-related gold deposits.  The study area is found the placer and  primary gold hosted by metamorphic rocks. The gold is evidently derived from gold-bearing quartz veins hosted by Pompangeo Metamorphic Complex (PMC. These quartz veins are currently recognized in metamorphic rocks at Rumbia Mountains. The quartz veins are mostly sheared/deformed, brecciated, irregular vein, segmented and  relatively massive and crystalline texture with thickness from 1 cm to 15.7 cm. The wallrock are generally weakly altered. Hydrothermal alteration types include sericitization, argillic, inner propylitic, propylitic, carbonization and carbonatization. There some precious metal identified consist of native gold and ore mineralization including pyrite (FeS2, chalcopyrite (CuFeS2, hematite (Fe2O3, cinnabar (HgS, stibnite (Sb2S3 and goethite (FeHO2. The veins contain erratic gold in various grades from below detection limit <0.0002 ppm to 18.4 ppm. Based on those characteristics, it obviously indicates that the primary gold deposit present in the study area is of orogenic gold deposit type. The orogenic gold deposit is one of the new targets for exploration in Indonesia

  6. Geochemical Signature of Mesozoic Volcanic and Granitic Rocks in Madina Regency Area, North Sumatra, Indonesia, and its Tectonic Implication

    Directory of Open Access Journals (Sweden)

    Iskandar Zulkarnain

    2014-06-01

    Full Text Available http://dx.doi.org/10.17014/ijog.vol4no2.20094Five samples consisting of two Permian-Triassic basalts, two Triassic-Jurassic granitic rocks, and a Miocene andesite were collected from the Madina Regency area in North Sumatra that is regionally situated on the West Sumatra Block. Previous authors have proposed three different scenarios for the geological setting of West Sumatra Permian Plutonic-Volcanic Belt, namely an island-arc, subduction related continental margin arc, and continental break-up. Petrographic analysis of the Mesozoic basaltic samples indicates that they are island-arcs in origin; however their trace element spider diagram patterns (Rock/MORB ratio also show the character of back-arc marginal basin, besides the island-arc. Furthermore, their REE spider diagram patterns (Rock/ Chondrite ratio clearly reveal that they were actually generated in a back-arc marginal basin tectonic setting. Meanwhile, the two Mesozoic granitic rocks and the Miocene andesite reflect the character of an active continental margin. Their spider diagram patterns show a significant enrichment on incompat- ible elements, usually derived from fluids of the subducted slab beneath the subduction zone. The high enrichment on Th makes their plots on Ta/Yb versus Th/Yb diagram are shifted to outside the active continental margin field. Although the volcanic-plutonic products represent different ages, their La/Ce ratio leads to a probability that they have been derived from the same magma sources. This study offers another different scenario for the geological setting of West Sumatra Permian Plutonic-Volcanic Belt, where the magmatic activities started in a back-arc marginal basin tectonic setting during the Permian-Triassic time and changed to an active continental margin during Triassic to Miocene. The data are collected through petrographic and chemical analyses for major, trace, and REE includ- ing literature studies.  

  7. Geochemical Signature of Mesozoic Volcanic and Granitic Rocks in Madina Regency Area, North Sumatra, Indonesia, and its Tectonic Implication

    Directory of Open Access Journals (Sweden)

    Iskandar Zulkarnain

    2014-06-01

    Full Text Available http://dx.doi.org/10.17014/ijog.vol4no2.20094Five samples consisting of two Permian-Triassic basalts, two Triassic-Jurassic granitic rocks, and a Miocene andesite were collected from the Madina Regency area in North Sumatra that is regionally situated on the West Sumatra Block. Previous authors have proposed three different scenarios for the geological setting of West Sumatra Permian Plutonic-Volcanic Belt, namely an island-arc, subduction related continental margin arc, and continental break-up. Petrographic analysis of the Mesozoic basaltic samples indicates that they are island-arcs in origin; however their trace element spider diagram patterns (Rock/MORB ratio also show the character of back-arc marginal basin, besides the island-arc. Furthermore, their REE spider diagram patterns (Rock/ Chondrite ratio clearly reveal that they were actually generated in a back-arc marginal basin tectonic setting. Meanwhile, the two Mesozoic granitic rocks and the Miocene andesite reflect the character of an active continental margin. Their spider diagram patterns show a significant enrichment on incompat- ible elements, usually derived from fluids of the subducted slab beneath the subduction zone. The high enrichment on Th makes their plots on Ta/Yb versus Th/Yb diagram are shifted to outside the active continental margin field. Although the volcanic-plutonic products represent different ages, their La/Ce ratio leads to a probability that they have been derived from the same magma sources. This study offers another different scenario for the geological setting of West Sumatra Permian Plutonic-Volcanic Belt, where the magmatic activities started in a back-arc marginal basin tectonic setting during the Permian-Triassic time and changed to an active continental margin during Triassic to Miocene. The data are collected through petrographic and chemical analyses for major, trace, and REE includ- ing literature studies.  

  8. Geomorphological analysis, monitoring and modeling of large rock avalanches in northern Chile (Iquique area) for regional hazard assessment.

    Science.gov (United States)

    Yugsi Molina, F. X.; Hermanns, R. L.; Crosta, G. B.; Dehls, J.; Sosio, R.; Sepúlveda, S. A.

    2012-04-01

    Iquique is a city of about 215,000 inhabitants (Chilean national census 2002) settled on one of the seismic gaps in the South American subduction zone, where a M >8 earthquake with overdue return periods of ca. 100 yr is expected in the near future. The city has only two access roads coming from the east and south. The road to the east comes down along the escarpment that connects the Coastal Cordillera to the Coastal Plain. The road has been blocked by small magnitude earthquake-triggered landslides at least once in recent years. The second road, coming from the south, crosses along the Coastal Plain and connects the city to the airport where at least ten ancient debris deposits related to rock avalanches are found. These facts show the importance of determining the effects of a future high magnitude earthquake on the stability of the slopes in the area and the impact of possible slope failures on people, infrastructure and emergency management. The present work covers an area of approximately 130 km2 parallel to the coastline to the south of Iquique, divided into the two main morphological units briefly mentioned above. The eastern part corresponds to the Coastal Cordillera, a set of smoothed hills and shallow valleys that reaches up to 1200 m asl. This sector is limited to the west by a steep escarpment followed by the Coastal Plain and a narrow emerged marine plateau (1-3 km wide) locally overlaid by deposits of recent rock avalanches. Rock avalanche events have recurrently occurred at two sites to the north and center of the study area on the Coastal Cordillera escarpment. Another major single event has been mapped to the south. Marls, red and black shales, and shallow marine glauconitic deposits from Jurassic constitute the source rock for the rock avalanches in all sites. Clusters of deposits are found in the first two sites (retrogressive advance) with younger events running shorter distances and partially overlaying the older ones. Multiple lobes have been

  9. Chronology and Geochemistry of Mesozoic Volcanic Rocks in the Linjiang Area, Jilin Province and their Tectonic Implications

    Institute of Scientific and Technical Information of China (English)

    YU Yang; XU Wenliang; PEI Fuping; YANG Debin; ZHAO Quanguo

    2009-01-01

    Zircon U-Pb ages and geochemical analytical results are presented for the volcanic rocks of the Naozhigou, Ergulazi, and Sidaogou Formations in the Linjiang area, southeastern Jilin Province to constrain the nature of magma source and their tectonic settings. The Naozhigou Formation is composed mainly of andesite and rhyolite and its weighted mean 206Pb/238U age for 13 zircon grains is 2224±1 Ma. The Ergulazi Formation consists of basaltic andesite, basaltic trachyandesite, and andesite, and six grains give a weighted mean 206Pb/238U age of 131±4 Ma. The Sidaogou Formation consists mainly of trachyandesite and rhyolite, and six zircon grains yield a weighted mean 206Pb/238U age of113±4 Ma. The volcanic rocks have SiO2=60.24%-77.46%, MgO=0.36%-1.29% (Mg#=0.32-0.40) for the Naozhigou Formation, SiO2=51.60%-59.32 %, MgO=3.70 %-5.54% (Mg#=0.50-0.60) for the Ergulazi Formation, and SiO2=58.28%-76.32%, MgO=0.07%-1.20% (Mg#=0.14-0.46) for the Sidaogou Formation. The trace element analytical results indicate that these volcanic rocks are characterized by enrichment in light rare earth elements (LREEs) and large ion lithophile elements (LILEs), relative depletion in heavy rare earth elements (HREEs) and high field strength elements (HFSEs, Nb, Ta, and Ti), and negative Eu anomalies. Compared with the primitive mantle, the Mesozoic volcanic rocks in the Linjiang area have relatively high initial 87Sr/86Sr ratios (0.7053-0.7083) and low eNd(t) values (-8.38 to -2.43), and display an EMII trend. The late Triassic magma for the Naozhigou Formation could be derived from partial melting of a newly accretional crust with the minor involvement of the North China Craton basement and formed under an extensional environment after the collision of the Yangtze Craton and the North China Craton. The Early Cretaceous volcanic rocks for the Ergulazi and Sidaogou Formations could be formed under the tectonic setting of an active continental margin related to the westward snbduction of

  10. On the influence of topographic, geological and cryospheric factors on rock avalanches and rockfalls in high-mountain areas

    Directory of Open Access Journals (Sweden)

    L. Fischer

    2012-01-01

    Full Text Available The ongoing debate about the effects of changes in the high-mountain cryosphere on rockfalls and rock avalanches suggests a need for more knowledge about characteristics and distribution of recent rock-slope instabilities. This paper investigates 56 sites with slope failures between 1900 and 2007 in the central European Alps with respect to their geological and topographical settings and zones of possible permafrost degradation and glacial recession. Analyses of the temporal distribution show an increase in frequency within the last decades. A large proportion of the slope failures (60% originated from a relatively small area above 3000 m a.s.l. (i.e. 10% of the entire investigation area. This increased proportion of detachment zones above 3000 m a.s.l. is postulated to be a result of a combination of factors, namely a larger proportion of high slope angles, high periglacial weathering due to recent glacier retreat (almost half of the slope failures having occurred in areas with recent deglaciation, and widespread permafrost occurrence. The lithological setting appears to influence volume rather than frequency of a slope failure. However, our analyses show that not only the changes in cryosphere, but also other factors which remain constant over long periods play an important role in slope failures.

  11. Integrated techniques to evaluate the features of sedimentary rocks of archaeological areas of Sicily

    Directory of Open Access Journals (Sweden)

    Maria Brai

    2004-02-01

    Full Text Available Sicily includes a great variety of lithologies, giving a high complexity to the geologic landscape. Their prevalent lithology is sedimentary. It is well known that rocks of sedimentary origin, compared with metamorphic and volcanic deposits, can be relatively soft and hence fairly easy to model. Nevertheless, this workability advantage is a drawback for Cultural Heritage applications. In fact, these materials show a high porosity, with pore-size distributions that lead to deterioration through absorption of water. In this paper, several sedimentary rocks used in historical Cultural Heritage items of Sicily, from "Magna Graecia" to nowadays, are classified for mineralogical features, chemical composition, and for porosity. Particularly, some samples collected in quarries relevant to the archaeological sites of 41 Agrigento, Segesta and Selinunte will be considered and characterized using integrated techniques (XRD, XRF, NMR and CT. Data on samples obtained in laboratory will be compared with the relevant values measured in situ on monuments of historical-cultural interest of the quoted archaeological places.

  12. SHRIMP dating of volcanic rock in the Zhangwu-Heishan area, West Liaoning province, China: Its relationship with coal-bearing strata

    Institute of Scientific and Technical Information of China (English)

    Cai Houan; Xu Debin; Li Baofang; Shao Longyi

    2011-01-01

    The Zhangwu-Heishan area is located to the east of the Fuxin-Yixian Basin and is mostly covered with volcanic rock.At various periods,different geologists had varying opinions about their age and periods of volcanic eruptions,especially on sequences between volcanic rock and main coal-beating strata,which affect the direction of searching for coal,as well as prospecting the entire research area.During our study,we carried out detailed field investigations in this research area; observed and recorded the main representative outcrops of volcanic rock.We collected over 20 volcanic rock samples and tested the Sensitive High Resolution Ion Microprobe Ⅱ (SHRIMP Ⅱ) U-Pb isotope age of 11 samples.The age of our volcanic rock samples ranged between 56.0 ± 2.9 and 132.3 ± 2.3 Ma.After taking earlier investigations into consideration,we concluded that,except for a suite of paleogene olivine basalt,the volcanic rock in the Zhangwu-Heishan area is younger than the coal-beating Shahai Formation.It is therefore most unlikely to find coal seams equivalent to those of the early Cretaceous Shahai Formation in Fuxin Basin below volcanic rock.

  13. Landslides and rock fall processes in the proglacial area of the Gepatsch glacier, Tyrol, Austria - Quantitative assessment of controlling factors and process rates

    Science.gov (United States)

    Vehling, Lucas; Rohn, Joachim; Moser, Michael

    2013-04-01

    Due to the rapid deglaciation since 1850, lithological structures and topoclimatic factors, mass movements like rock fall, landslides and complex processes are important contributing factors to sediment transport and modification of the earth's surface in the steep, high mountain catchment of the Gepatsch reservoir. Contemporary geotechnical processes, mass movement deposits, their source areas, and controlling factors like material properties and relief parameters are mapped in the field, on Orthofotos and on digital elevation models. The results are presented in an Arc-Gis based geotechnical map. All mapped mass movements are stored in an Arc-Gis geodatabase and can be queried regarding properties, volume and controlling factors, so that statistical analyses can be conducted. The assessment of rock wall retreat rates is carried out by three different methods in multiple locations, which differ in altitude, exposition, lithology and deglaciation time: Firstly, rock fall processes and rates are investigated in detail on five rock fall collector nets with an overall size of 750 m2. Rock fall particles are gathered, weighed and grain size distribution is detected by sieving and measuring the diameter of the particles to distinct between rock fall processes and magnitudes. Rock wall erosion processes like joint formation and expansions are measured with high temporal resolution by electrical crack meters, together with rock- and air temperature. Secondly, in cooperation with the other working groups in the PROSA project, rock fall volumes are determined with multitemporal terrestrial laserscanning from several locations. Lately, already triggered rock falls are accounted by mapping the volume of the deposit and calculating of the bedrock source area. The deposition time span is fixed by consideration of the late Holocene lateral moraines and analysing historical aerial photographs, so that longer term rock wall retreat rates can be calculated. In order to limit

  14. K-Ar dating, whole-rock and Sr-Nd isotope geochemistry of calc-alkaline volcanic rocks around the Gümüşhane area: implications for post-collisional volcanism in the Eastern Pontides, Northeast Turkey

    Science.gov (United States)

    Aslan, Zafer; Arslan, Mehmet; Temizel, İrfan; Kaygusuz, Abdullah

    2014-04-01

    Volcanic rocks from the Gümüşhane area in the southern part of the Eastern Pontides (NE Turkey) consist mainly of andesitic lava flows associated with tuffs, and rare basaltic dykes. The K-Ar whole-rock dating of these rocks range from 37.62 ± 3.33 Ma (Middle Eocene) to 30.02 ± 2.84 Ma (Early Oligocene) for the andesitic lava flows, but are 15.80 ± 1.71 Ma (Middle Miocene) for the basaltic dykes. Petrochemically, the volcanic rocks are dominantly medium-K calc-alkaline in composition and show enrichment of large ion lithophile elements, as well as depletion of high field strength elements, thus revealing that volcanic rocks evolved from a parental magmas derived from an enriched mantle source. Chondrite-normalized rare-earth element patterns of the volcanic rocks are concave upwards with low- to-medium enrichment (LaCN/LuCN = 3.39 to 12.56), thereby revealing clinopyroxene- and hornblende-dominated fractionations for andesitic-basaltic rocks and tuffs, respectively. The volcanic rocks have low initial 87Sr/86Sr ratios (0.70464 to 0.70494) and ɛNd(i) values (+1.11 to +3.08), with Nd-model ages (TDM) of 0.68 to 1.02 Ga, suggesting an enriched lithospheric mantle source of Proterozoic age. Trace element and isotopic data, as well as the modelling results, show that fractional crystallization and minor assimilation played an important role in the evolution of the volcanic rocks studied. The Eocene to Miocene volcanism in the region has resulted from lithospheric delamination and the associated convective thinning of the mantle, which led to the partial melting of the subduction-metasomatized lithospheric mantle.

  15. Changes of ecological conditions induced by rock tunneling in Laoshan Mountain area

    Institute of Scientific and Technical Information of China (English)

    Xiaozhao LI; Xiaobao ZHAO; Zhongsheng WANG

    2008-01-01

    Through field investigation, this paper exam-ined the changes of ecological conditions induced by tun-nel construction in Laoshan Mountain area, Nanjing, Jiangsu Province, P. R. China. The effects of habitat frag-mentation and edge effect are examined and discussed. It is found that the environmental factors and vegetation situation have been influenced by the tunneling activity, and the disturbed area is approaching the sampling patch centre. The changed ecological conditions are beneficial for the settlement and growth of some herb and shrub species, and are unfavorable for the existence and growth of saplings, especially for the predominant species (e.g., robur) in this area. If the time of habitat fragmentation is long enough and there is no supplement from external areas, some vegetation species in the engineering influ-encing area will deteriorate, or even diminish in the future. The results can be used as a reference for the long-term ecological study in this area.

  16. Geochemistry and tectonomagatic setting of Tertiary volcanic rocks of the Kangan area, northeast of Sarbisheh, southern Khorasan

    Directory of Open Access Journals (Sweden)

    Mahshid Malekian Dastjerdi

    2017-02-01

    Full Text Available Introduction The study area is located 12km away from the north east of Sarbisheh at the eastern border of the Lut block (Karimpour et al., 2011; Richards et al., 2012. The magmatic activity in the Lut blockhas begun in the middle Jurassic (165-162 Ma and reached its peak in the Tertiary age (Jung et al., 1983; Karimpour et al., 2011. Volcanic and subvolcanic rocks in the Tertiary age cover over half of the Lut block with up to 2000 m thickness and they were formed due to subduction prior to the collision of the Arabian and Asian plates (Jung et al., 1983; Karimpour et al., 2011. In the Kangan area, the basaltic lavas cropped out beyond the above intermediate to acid volcanic rocks. In this area, bentonite and perlite deposits have an economic importance. The main purpose of this paper is to present a better understanding of the tectono-magmatic settings of volcanic rocks in the northeast of Sarbisheh, east of Iran based on their geochemical characteristics. Materials and methods Fifteen samples were analyzed for major elements by inductively coupled plasma (ICP technologies and trace elements by using inductively coupled plasma mass spectrometry (ICP-MS, following a lithium metaborate/tetraborate fusion and nitric acid total digestion, at the Acme laboratories, Vancouver, Canada. Results The Kangan area is located at the northeast of Sarbishe, Southern Khorasan and the eastern border of the Lut block. In this area, basaltic lavas have cropped out above intermediate to acid lavas such as andesite, dacite, rhyolite (sometimes perlitic .The main minerals in the basalt are plagioclase, olivine and pyroxene, in andesite contain plagioclase, pyroxene, biotite and amphibole and in acid rocks include plagioclase, quartz, sanidine, biotite and amphibole. Intermediate to acid rocks have medium to high-K calc-alkaline nature and basalt is alkaline. Enrichment in LREE relative to HREE (Ce/Yb= 21.14-28.7, high ratio of Zr/Y(4.79- 10.81, enrichment in LILE

  17. Dating and source determination of volcanic rocks from Khunik area (South of Birjand, South Khorasan using Rb-Sr and Sm-Nd isotopes

    Directory of Open Access Journals (Sweden)

    Somayeh Samiee

    2016-12-01

    Full Text Available The Khunik area is located in the south of Birjand, Khorasan province, in the eastern margin of Lut block. Tertiary volcanic rocks have andesite to trachy-andesite composition. Dating analyzing by Rb-Sr method on plagioclase and hornblende as well as whole-rock isochron method was performed on pyroxene-hornblende andesite rock unit. On this basis the emplacement age is Upper Paleocene (58±11 Ma. These rocks have initial 87Sr/86Sr and εNd 0.7046-0.7049 and 2.16-3.12, respectively. According to isotopic data, volcanic rocks originated from depleted mantle and have the least crust contamination while it was fractionated. Geochemically, Khunik volcanic rocks have features typical of calk-alkaline to shoshonite and are metaluminous. Enrichment in LILEs and typical negative anomalies of Nb and Ti are evidences that the volcanic rocks formed in a subduction zone and active continental margin. Modeling suggests that these rocks were derived dominantly from 1–5% partial melting of a mainly spinel garnet lherzolite mantle source that is metasomatized by slab-derived fluid.

  18. Cenozoic volcanic rocks in the Belog Co area, Qiangtang, northern Tibet, China: Petrochemical evidence for partial melting of the mantle-crust transition zone

    Institute of Scientific and Technical Information of China (English)

    LAI Shaocong; QIN Jiangfeng; LI Yongfeng; LIU Xin

    2007-01-01

    Neogene volcanic rocks in the Belog Co area, Qiangtang, northern Tibet, are represented by a typical intermediate-basic and intermediate alkaline rock association, with latite-trachyte as the main rock type. The results of chemical analysis are: SiO2=52%-62%, Al2O3>15%, Na2O/K2O>1 and MgO<3.30%. In addition, the volcanic rocks are LREE-enriched with LREE/HREE=10-13, (La/Yb)N=15-19, and show a weak negative Eu anomaly with δEu=0.71-0.89. The close relationship between Mg# and SiO2 and the co-variation of the magmatophile elements and ultra-magmatophile elements such as La/Sm-La and Cr-Tb indicate that this association of volcanic rocks is the product of comagmatic fractional crystallization. The rock association type and lower Sm/Yb values (Sm/Yb=3.23-3.97) imply that this association of volcanic rocks should have originated from partial melting of spinel lherzolite in the lithospheric mantle. On the other hand, the weak negative Eu anomaly and relative depletion in Nb, Ta and Ti reflect the features of terrigenous magma. So the Neogene Belog Co alkaline volcanic rocks should be the result of partial melting of the special crust-mantle transition zone on the Qinghai-Tibet Plateau.

  19. Pore Scale Heterogeneity in the Mineral Distribution and Surface Area of Porous Rocks

    Science.gov (United States)

    Lai, Peter; Krevor, Sam

    2015-04-01

    An important control on rate of interfacial processes between minerals and aqueous solutions such as nucleation of solids, and mineral dissolution and growth is reactive surface area. In geochemical modelling, the continuum hypothesis is based on the assumption that the system can be represented by a sufficiently large number of representative elemental volumes. There has been recent interest in studying the impact of this assumption on reaction-transport coupled systems. In this study, the impact of pore-scale heterogeneity on the distribution of reactive surface area is discussed. 3D images obtained using x-ray micro-tomography were used to characterise the distribution of reactive surface area. The results were compared to independent observations. Mineral identification using x- ray diffraction and fluorescence suggested general agreement with CT analysis. Nitrogen BET surface areas were one to two orders of magnitude higher than measurements from x-ray imagery. Co- registered images of Berea sandstone from x-ray and energy dispersive spectroscopy imagery suggested that quartz, K-feldspar and most clays could be identified. However, minor minerals such as albite and illite did not exhibit enough contrast. In Berea sandstone, mineral surface area fraction was poorly correlated to the mineral volumetric fraction. Clay and feldspar minerals exhibited higher surface area fractions than bulk mineralogy suggested. In contrast, in the Edwards carbonate samples, modal mineral composition correlated with mineral-specific surface area. Berea sandstone revealed a characteristic pore size at which a surface area distribution may be used to quantify heterogeneity. Conversely, the carbonate samples suggested a continuous range of pore sizes across length scales. A comparison with pore network model simulations from the literature was made. First order estimates of mineral specific correlations between geometric area measured in the x-ray images were used to convert the CT

  20. Assessment of Rock Magnetic Parameters for Fly Ash Pollution Screening in Topsoil of the Deccan Trap Basalt Area, India

    Science.gov (United States)

    Blaha, U.; Basavaiah, N.; Das, P. K.; Deenadayalan, K.

    2012-04-01

    Rock magnetic parameters of highly magnetic topsoil of the Deccan Trap basalt area are evaluated for their suitability for efficient environmental magnetic pollution screening. Parameters, such as magnetic susceptibility (χ), frequency dependence of magnetic susceptibility (κ fd%), anhysteretic remanent magnetization (ARM), saturation isothermal remanent magnetization (SIRM), soft isothermal remanent magnetization (Soft IRM), as well as thermo-magnetic analysis (κ-T) are compared and assessed for best depiction of topsoil contamination due to ash deposition around the Nashik thermal power station (NTPS). Fifty-five topsoil samples, collected along north-south and west-east stretching transects of 24 km length, are the basis for evaluation of the specific ash distribution pattern around the plant and its adjacent ash pond. Similar decline of the magnetic signals with increasing distance from the point source is observed in the concentration dependent magnetic parameters and can be modeled. The magnetic grain size parameters instead reveal increasing trends with increasing distance. Verwey-transition and Hopkinson peak obtained from κ-T analyses demonstrate to be important parameters to prove fly ash accumulation in soils of basaltic origin. The importance of magnetic parameters for indirect tracing of pollutants, such as heavy metals, is shown by Pb, Zn and Cu data, revealing similar distribution pattern as obtained from the concentration dependent magnetic parameters. Confirmation of the presence of a very high amount of ash particles in the vicinity of the NTPS and a low number of particles in more distant areas is provided by scanning electron microscopy (SEM) on quantitatively extracted magnetic particles at 5.5 km and 11.9 km distance in eastern direction. The investigation demonstrates that the majority of the rock magnetic parameters has the potential to be successfully applied in environmental magnetic studies in areas with high magnetic background

  1. Petrology and petrogenesis of the Eocene Volcanic rocks in Yildizeli area (Sivas), Central Anatolia, Turkey

    Science.gov (United States)

    Doğa Topbay, C.; Karacık, Zekiye; Genç, S. Can; Göçmengil, Gönenç

    2015-04-01

    -Na plagioclase + hornblend ± pyroxene ± biotite + opaques in a matrix comprised of mostly glass, microlites or crypto to micro crystalline feldspars. All the lavas show mainly pilotaxitic, intersertal, cumulophyric and poikilitic textures. Geochemically, Yıldızeli lavas ranging in composition from basalt to trachyandesite displaying the calc-alkaline affinity with medium-K and shoshonitic character. All intermediate and basic volcanic rocks show enrichment in large ion lithophile elements (LILE) and light rare earth elements (LREE) relative to the high field strength elements (HFSE) such as Nb, Ta, Zr and Ti. Volcanic rocks of the Yıldızeli region display the following range in Sr and Nd initial isotope ratios: 87Sr/86Sr = 0.704389 to 0.706291 and 143Nd/144Nd = 0.512671. The major- trace element geochemistry and isotopic values suggest that Yıldızeli volcanics derived possibly from a mantle source which was modified by subduction related fluids or was contaminated by the continental crustal components.

  2. Ar-Ar geochronology of Late Mesozoic volcanic rocks from the Yanji area,NE China and tectonic implications

    Institute of Scientific and Technical Information of China (English)

    LI ChaoWen; GUO Feng; FAN WeiMing; GAO XiaoFeng

    2007-01-01

    Ar-Ar dating results of late Mesozoic-Cenozoic volcanic rocks from the Yanji area, NE China provide a new volcano-sedimentary stratigraphic framework. The previously defined "Triassic-Jurassic" volcanic rocks(including those from Sanxianling, Tuntianying, Tianqiaoling and Jingouling Fms.)were erupted during 118-106Ma,corresponding to Early Cretaceous. The new eruption age span is slightly younger than the main stage(130-120 Ma)of the extensive magmatism in the eastern Central Asian Orogenic Belt and its adjacent regions. Subduction-related adakites occurring in the previously defined Quanshuicun Fm. Were extruded at ca.55 Ma. Based on these new Ar-Ar ages, the late Mesozoic to Palaeocene volcano-sedimentary sequences is rebuilt as:Tuopangou Fm., Sanxianling/Tuntianying Fm.(118-115 Ma),Malugou/Tianqiaoling Fm.(K1),Huoshanyan/Jingouling Fm.(108-106 Ma),Changcai Fm.(K2),Quanshuicun Fm.(~55 Ma)and Dalazi Fm. Our results suggest that subduction of the Palaeo-Pacific Ocean beneath the East Asian continental margin occurred during 106to 55 Ma. Consistent with the paleomagnetic observations and magmatic records which indicated that the Izanagi-Farallon ridge subduction beneath the southwestern Japan took place during 95-65 Ma.

  3. Ar-Ar geochronology of Late Mesozoic volcanic rocks from the Yanji area, NE China and tectonic implications

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Ar-Ar dating results of late Mesozoic-Cenozoic volcanic rocks from the Yanji area, NE China provide a new volcano-sedimentary stratigraphic framework. The previously defined “Triassic-Jurassic” volcanic rocks (including those from Sanxianling, Tuntianying, Tianqiaoling and Jingouling Fms.) were erupted during 118―106 Ma, corresponding to Early Cretaceous. The new eruption age span is slightly younger than the main stage (130―120 Ma) of the extensive magmatism in the eastern Central Asian Orogenic Belt and its adjacent regions. Subduction-related adakites occurring in the previously defined Quanshuicun Fm. were extruded at ca. 55 Ma. Based on these new Ar-Ar ages, the late Mesozoic to Palaeocene volcano-sedimentary sequences is rebuilt as: Tuopangou Fm., Sanxianling/Tuntianying Fm. (118―115 Ma), Malugou/Tianqiaoling Fm. (K1), Huoshanyan/Jingouling Fm. (108―106 Ma), Changcai Fm. (K2), Quanshuicun Fm. (~55 Ma) and Dalazi Fm. Our results suggest that subduction of the Pa- laeo-Pacific Ocean beneath the East Asian continental margin occurred during 106 to 55 Ma, consistent with the paleomagnetic observations and magmatic records which indicated that the Izanagi-Farallon ridge subduction beneath the southwestern Japan took place during 95―65 Ma.

  4. Depositional framework and regional correlation of pre-Carboniferous metacarbonate rocks of the Snowden Mountain area, central Brooks Range, Northern Alaska

    Science.gov (United States)

    Dumoulin, J.A.; Harris, A.G.

    1994-01-01

    This report describes lithofacies, conodont biostratigraphy and biofacies, and depositional environments of Proterozoic(?) through Devonian metacarbonate rocks in the Snowden Mountain area. These rocks are correlated with successions on the Seward Peninsula and across the Brooks Range. Lithologic and paleobiogeographic data suggest that these successions formed along a single continental margin which had faunal exchange with both North America and Siberia, rather than on a series of discrete platforms juxtaposed by later tectonic events.

  5. Mapping the productive sands of Lower Goru Formation by using seismic stratigraphy and rock physical studies in Sawan area, southern Pakistan: A case study

    KAUST Repository

    Munir, K.

    2011-02-24

    This study has been conducted in the Sawan gas field located in southern Pakistan. The aim of the study is to map the productive sands of the Lower Goru Formation of the study area. Rock physics parameters (bulk modulus, Poisson\\'s ratio) are analysed after a detailed sequence stratigraphic study. Sequence stratigraphy helps to comprehend the depositional model of sand and shale. Conformity has been established between seismic stratigraphy and the pattern achieved from rock physics investigations, which further helped in the identification of gas saturation zones for the reservoir. Rheological studies have been done to map the shear strain occurring in the area. This involves the contouring of shear strain values throughout the area under consideration. Contour maps give a picture of shear strain over the Lower Goru Formation. The identified and the productive zones are described by sands, high reflection strengths, rock physical anomalous areas and low shear strain.

  6. Closure Report for Corrective Action Unit 230: Area 22 Sewage Lagoons and Corrective Action Unit 320: Area 22 Desert Rock Airport Strainer Box Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    D. S. Tobiason

    2001-07-01

    This Closure Report (CR) describes the remediation activities performed and the results of verification sampling conducted at Corrective Action Unit (CAU) 230, Area 22 Sewage Lagoons and CAU 320, Area 22 Desert Rock Airport Strainer Box. The CAU is currently listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO, 1996). The CAU is located in Area 22 of the Nevada Test Site (NTS) (Figure 1) and consists of the following Corrective Action Sites (CASs): 22-03-01- Sewage Lagoon (CAU 230); and 22-99-01- Strainer Box (CAU 320). Included with CAS 22-99-01 is a buried Imhoff tank and a sludge bed. These CAUs will be collectively referred to in this plan as the Area 22 Sewage Lagoons site. Site characterization activities were done during September 1999. Characterization of the manholes associated with the septic system leading to the Imhoff tank was done during March 2000. The results of the characterization presented in the Corrective Action Decision Document (CADD) indicated that only the sludge bed (CAS 22-99-01) contained constituents of concern (COC) above action levels and required remediation (U.S. Department of Energy, Nevada Operations Office [DOE/NV], 2000a).

  7. Geology of Precambrian rocks and isotope geochemistry of shear zones in the Big Narrows area, northern Front Range, Colorado

    Science.gov (United States)

    Abbott, Jeffrey T.

    1970-01-01

    Rocks within the Big Narrows and Poudre Park quadrangles located in the northern Front Range of Colorado are Precambrian metasedimentary and metaigneous schists and gneisses and plutonic igneous rocks. These are locally mantled by extensive late Tertiary and Quaternary fluvial gravels. The southern boundary of the Log Cabin batholith lies within the area studied. A detailed chronology of polyphase deformation, metamorphism and plutonism has been established. Early isoclinal folding (F1) was followed by a major period of plastic deformation (F2), sillimanite-microcline grade regional metamorphism, migmatization and synkinematic Boulder Creek granodiorite plutonism (1.7 b.y.). Macroscopic doubly plunging antiformal and synformal structures were developed. P-T conditions at the peak of metamorphism were probably about 670?C and 4.5 Kb. Water pressures may locally have differed from load pressures. The 1.4 b.y. Silver Plume granite plutonism was post kinematic and on the basis of petrographic and field criteria can be divided into three facies. Emplacement was by forcible injection and assimilation. Microscopic and mesoscopic folds which postdate the formation of the characteristic mineral phases during the 1.7 b.y. metamorphism are correlated with the emplacement of the Silver Plume Log Cabin batholith. Extensive retrograde metamorphism was associated with this event. A major period of mylonitization postdates Silver Plume plutonism and produced large E-W and NE trending shear zones. A detailed study of the Rb/Sr isotope geochemistry of the layered mylonites demonstrated that the mylonitization and associated re- crystallization homogenized the Rb87/Sr 86 ratios. Whole-rock dating techniques applied to the layered mylonites indicate a probable age of 1.2 b.y. Petrographic studies suggest that the mylonitization-recrystallization process produced hornfels facies assemblages in the adjacent metasediments. Minor Laramide faulting, mineralization and igneous activity

  8. The contribution of PSInSAR interferometry to landslide susceptibility assessment in weak rock-dominated areas

    Science.gov (United States)

    Oliveira, Sérgio C.; Zêzere, José L.; Catalão, João; Nico, Giovanni

    2015-04-01

    In the Grande da Pipa river basin (north of Lisbon, Portugal), 64% of the landslides inventoried occur on a particular weak rock lithological unit composed by clay and with sandstone intercalations, that is present in 58% of the study (Oliveira et al., 2014). Deep-seated slow moving rotational slides occur essentially on this lithological unit and are responsible for the major damages verified along roads and buildings in the study area. Within this context, landslide hazard assessment, is limited by two major constrains: (i) the slope instability signs may not be sufficiently clear and observable and consequently may not be correctly identifiable through traditional geomorphologic survey techniques and (ii) the non-timely recognition of precursor signs of instability both in landslides activated for the first time and in previously landslide-affected areas (landslide reactivation). To encompass these limitations, the Persistent Scatterer synthetic aperture radar interferometry technique is applied to a data set of 16 TerraSAR-X SAR images, from April of 2010 to March of 2011, available for a small test site of 12.5 square kilometers (Laje-Salema) located on south-central part of the study area. This work's specific objectives are the following: (i) to evaluate the capacity of the Persistent Scatterer displacement maps in assessing landslide susceptibility at the regional scale, and (ii) to assess the capacity of landslide susceptibility maps based on historical landslide inventories to predict the location of actual terrain displacement measured by the Persistent Scatterers technique. Landslide susceptibility was assessed for the test site using the Information Value bivariate statistical method and the susceptibility scores were exported to the Grande da Pipa river basin. The independent validation of the landslide susceptibility maps was made using the historical landslide inventory and the Persistent Scatterer displacement map. Results are compared by computing

  9. WELL LOGGING EVALUATION OF MARINE HYDROCARBON SOURCE ROCK IN TAZHONG AREA%塔中地区海相烃源岩测井评价

    Institute of Scientific and Technical Information of China (English)

    雷涛; 周文; 邓虎成; 赵安坤; 杨艺; 熊川

    2011-01-01

    To the low organic abundance and strong heterogeneity of the marine hydrocarbon source rock, this paper analyzes the well logging response characteristics of the marine hydrocarbon source rock in Tazhong area, and builds the plate for quantitative identification of Ordovician source rock in Tazhong area and the classification and identification model for marine source rock in the studied area. In the evaluation of organic matter abundance, the elastic parameters of hydrocarbon source rock, the ratio of uranium and thorium content, the difference of natural gamma, and the resistivity in Tazhong area are used as the input layers, and a BP neural network model based on the genetic algorithm is built. Practice shows that the TOC value predicated by this method is as accurate and reliable as the rock sample analysis result, providing the basis for the evaluation of effective hydrocarbon source rock.%针对海相烃源岩具有有机质丰度低和非均质性强的特点,分析了塔中地区海相烃源岩的测井响应特征,建立了塔中奥陶系烃源岩定量识别的图版及适合研究区海相烃源岩的分类识别模型.在有机质丰度评价方面,利用塔中地区烃源岩弹性参数、铀钍含量比、自然伽马的差值及电阻率作为输入层,建立了基于遗传算法的BP神经网络模型.实践表明,采用该方法预测的TOC值与岩石样品分析结果同样精确可靠,为评价有效烃源岩提供了依据.

  10. Content and distribution of fluorine in rock, clay and water in fluorosis area Zhaotong, Yunnan Province

    Energy Technology Data Exchange (ETDEWEB)

    Luo, K.; Li, H.; Feng, F. (and others) [Chinese Academy of Sciences, Beijing (China)

    2007-04-15

    About 160 samples of coal, pyritic coal balls, coal seam gangue, clay, corn, capsicum and drinking water were collected from the endemic fluorosis area of Zhenxiong and Weixin county, China to determine the fluorine content, distribution pattern and source in this fluorosis area. The study shows that the average fluorine content in the coal samples collected from 3 coal mines of the Late Permian coals in Zhenxiong and Weixin county, Zhaotong City, which are the main mining coals there, is 77.13 mg/kg. The average fluorine content coals collected form thee typical fluorosis villages in 72.56 mg/kg. Both of them are close to the world average and little low than the Chinese average. The fluorine content of drinking water is lower than 0.35 mg/L, the clay used as an additive for coal-burning and as a binfer in briquette-making by local residents has a high content of fluorine, ranging from 367-2,435 mg/kg, with the majority higher than 600 mg/kg and an average of 1,084.2 mg/kg. 29 refs., 5 tabs.

  11. Migration and Enrichment of Arsenic in the Rock-Soil-Crop Plant System in Areas Covered with Black Shale, Korea

    Directory of Open Access Journals (Sweden)

    Ji-Min Yi

    2003-01-01

    Full Text Available The Okchon black shale, which is part of the Guryongsan Formation or the Changri Formation of Cambro-Ordovician age in Korea provides a typical example of natural geological materials enriched with potentially toxic elements such as U, V, Mo, As, Se, Cd, and Zn. In this study, the Dukpyung and the Chubu areas were selected to investigate the migration and enrichment of As and other toxic elements in soils and crop plants in areas covered with black shale. Rock and soil samples digested in 4-acid solution (HCl+HNO3+HF+HClO4 were analyzed for As and other heavy metals by ICP-AES and ICP-MS, and plant samples by INAA. Mean concentration of As in Okchon black shale is higher than those of both world average values of shale and black shale. Especially high concentration of 23.2 mg As kg-1 is found in black shale from the Dukpyung area. Mean concentration of As is highly elevated in agricultural soils from the Dukpyung (28.2 mg kg-1 and the Chubu areas (32.6 mg kg-1. As is highly elevated in rice leaves from the Dukpyung (1.14 mg kg-1 and the Chubu areas (1.35 mg kg-1. The biological absorption coefficient (BAC of As in plant species decreases in the order of rice leaves > corn leaves > red pepper = soybean leaves = sesame leaves > corn stalks > corn grains. This indicates that leafy plants tend to accumulate As from soil to a greater degree than cereal products such as grains.

  12. Eo-Oligocene Oil Shales of the Talawi, Lubuktaruk, and Kiliranjao Areas, West Sumatra: Are they potential source rocks?

    Directory of Open Access Journals (Sweden)

    M. Iqbal

    2014-12-01

    Full Text Available DOI:10.17014/ijog.v1i3.198To anticipate the increasing energy demand, additional data and information covering unconventional fossil fuels such as oil shale must be acquired to promote the usage of alternative energy sources to crude oil. The Talawi and Lubuktaruk regions situated within intra-montane Ombilin Basin, and the Kiliranjao assumed to be a small intra montane basin are occupied by Eo-Oligocene sediments of Sangkarewang and Kiliran Formations, respectively. Field activity, geochemical screening techniques, and organic petrographic analysis, supported by SEM mode, are methods used. Most of the oil shale sequence is typically of an organically rich-succession comprising predominantly well-bedded, laminated and fissile, brownish to dark grey organic-rich shale and mudstone rocks. The exinite macerals within oil shale comprise mainly Pediastrum-lamalginite with minor cutinite, resinite, liptodetrinite, sporinite, bituminite, and rare Botryococcus-telalginite. Therefore; the oil shale deposits can be described as “lamosites”. Minor vitrinite maceral is also recognized. TOC analysis on selected shale samples corresponds to a fair up to excellent category of source rock characterization. The hydrogen index (HI for all samples shows a range of values from 207 - 864, and pyrolysis yield (PY ranges from 2.67 to 79.72 mg HC/g rock. The kerogen is suggested to be of mixed Type II and Type I autochthonous materials such as alginite, with minor allochthonous substances. Oil samples collected appear to be positioned within more oil prone rather than gas prone. Thermal maturity of the oil shales gained from Tmax value and production index (PI tends to show immature to marginally/early mature stage. A consistency in the thermal maturity level results by using both Tmax and vitrinite reflectance value is recognized. On the basis of  SEM analysis, the oil shale has undergone a late eodiagenetic process. Thereby, overall, vitrinite reflectance

  13. Eo-Oligocene Oil Shales of the Talawi, Lubuktaruk, and Kiliranjao Areas, West Sumatra: Are they potential source rocks?

    Directory of Open Access Journals (Sweden)

    M. Iqbal

    2014-12-01

    Full Text Available DOI:10.17014/ijog.v1i3.198To anticipate the increasing energy demand, additional data and information covering unconventional fossil fuels such as oil shale must be acquired to promote the usage of alternative energy sources to crude oil. The Talawi and Lubuktaruk regions situated within intra-montane Ombilin Basin, and the Kiliranjao assumed to be a small intra montane basin are occupied by Eo-Oligocene sediments of Sangkarewang and Kiliran Formations, respectively. Field activity, geochemical screening techniques, and organic petrographic analysis, supported by SEM mode, are methods used. Most of the oil shale sequence is typically of an organically rich-succession comprising predominantly well-bedded, laminated and fissile, brownish to dark grey organic-rich shale and mudstone rocks. The exinite macerals within oil shale comprise mainly Pediastrum-lamalginite with minor cutinite, resinite, liptodetrinite, sporinite, bituminite, and rare Botryococcus-telalginite. Therefore; the oil shale deposits can be described as “lamosites”. Minor vitrinite maceral is also recognized. TOC analysis on selected shale samples corresponds to a fair up to excellent category of source rock characterization. The hydrogen index (HI for all samples shows a range of values from 207 - 864, and pyrolysis yield (PY ranges from 2.67 to 79.72 mg HC/g rock. The kerogen is suggested to be of mixed Type II and Type I autochthonous materials such as alginite, with minor allochthonous substances. Oil samples collected appear to be positioned within more oil prone rather than gas prone. Thermal maturity of the oil shales gained from Tmax value and production index (PI tends to show immature to marginally/early mature stage. A consistency in the thermal maturity level results by using both Tmax and vitrinite reflectance value is recognized. On the basis of  SEM analysis, the oil shale has undergone a late eodiagenetic process. Thereby, overall, vitrinite reflectance

  14. Sedimentary connection between rock glaciers and torrential channels: definition, inventory and quantification from a test area in the south-western Swiss Alps

    Science.gov (United States)

    Kummert, Mario; Barboux, Chloé; Delaloye, Reynald

    2017-04-01

    Permafrsot creep is an important sediment transfer process in periglacial alpine hillslopes (Delaloye et al. 2010). Rock glaciers are the visible expression of mountain permafrost creep (Delaloye 2004). Large volumes of rock debris originating from headwalls, moraines and weathering deposits are slowly transported within rock glaciers from their rooting zone to their fronts. In the Alps, most rock glaciers can be considered as sediment traps, because the sediment output at their margin is usually limited (Gärtner-Roer 2012). However, cases of rock glacier supplying torrential channels with sediments have been documented (e.g. Lugon and Stoffel 2010, Delaloye et al. 2013) Such rock glaciers can act as a sediment source for the triggering of gravitational processes propagating further downstream. Moreover, in such configuration the amount of sediment available is not a finite volume but is gradually renewed or increased as the rock glacier advances. These cases are therefore very specific, especially in the perspective of natural hazards assessment and mitigation. However, in the Alps very little is known about such type of rock glaciers. In addition, the sediment transfer rates between the fronts of the rock glaciers and the torrents are often not known. In this context, our study aims at (i) defining better the configurations in which a sedimentary connection exists between rock glaciers and torrential channels, (ii) localizing the cases of active rock glaciers connected to the torrential network and (iii) estimating approximate sediment transfer rates between the fronts and the torrential gullies. For that purpose, an inventory method for the classification of torrential catchments based on the analysis of aerial images and the computation of connectivity indexes have been developped. In addition, sediment transfer rates were estimated taking into account the geometry of the frontal areas and the velocity rates of the rock glaciers derived from DInSAR data. In

  15. Upscaling of the specific surface area for reactive transport modelling in fractured rock

    Science.gov (United States)

    Cvetkovic, Vladimir

    2014-05-01

    The impact of flow heterogeneity on chemical transport from single to multiple fractures, is investigated. The emphasis is on the dynamic nature of the specific surface area (SSA) due to heterogeneity of the flow, relative to a purely geometrical definition. It is shown how to account for SSA as a random variable in modelling multi-component reactions. The flow-dependent SSA is interpreted probabilistically, following inert tracer particles along individual fractures. Upscaling to a fracture network is proposed as a time-domain random walk based on the statistics of SSA for single fractures. Statistics of SSA are investigated for three correlation structures of transmissivity, one classical multi-gaussian, and two non-Gaussian. The coefficient of variation of single fracture SSA decreases monotonously with the distance over the fracture length; the CV of the upscaled SSA reduces further such that after ca 20 fractures it is under 0.1 for a disconnected field, and around 0.2 for connected and multi-gaussian fields. This implies that after 10-20 fractures, uncertainty in SSA is significantly reduced, justifying the use of an effective value. A conservative, lower bound for the dimensionless upscaled effective SSA was found to be 1, suitable for all heterogeneity structures, assuming the cubic hydraulic law applicable.

  16. Hydrogeochemical studies of the Rustler Formation and related rocks in the Waste Isolation Pilot Plant Area, Southeastern New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, M.D.; Lambert, S.J.; Robinson, K.L. (eds.)

    1991-08-01

    Chemical, mineralogical, isotopic, and hydrological studies of the Culebra dolomite member of the Rustler Formation and related rocks are used to delineate hydrochemical facies and form the basis for a conceptual model for post-Pleistocene groundwater flow and chemical evolution. Modern flow within the Culebra in the Waste Isolation Pilot Plant (WIPP) area appears to be largely north-to-south; however, these flow directions under confined conditions are not consistent with the salinity distribution in the region surrounding the WIPP Site. Isotopic, mineralogical, and hydrological data suggest that vertical recharge to the Culebra in the WIPP area and to the immediate east and south has not occurred for several thousand years. Eastward increasing {sup 234}U/{sup 238}U activity ratios suggest recharge from a near-surface Pleistocene infiltration zone flowing from the west-northwest and imply a change in flow direction in the last 30,000 to 12,000 years. 49 refs., 34 figs., 4 tabs.

  17. Estimation Of The Mining Damage Risk In The Hypothetical Impact Area Of The Concurrent Processes Of Rock Mass Disorders

    Science.gov (United States)

    Piwowarski, Wiesław; Isakow, Zbigniew; Juzwa, Jacek

    2015-12-01

    The aim of this work is the estimation of the risk of mining damage occurrence, based on uncertain information regarding the impact of the concurrent processes of deformation and vibration. This problem concerns the experimental and theoretical description of the so-called critical phenomena occurring during the reaction mining area ↔ building object. Post-mining deformations of the rock mass medium and paraseismic vibrations can appear at a considerable distance from the sub-area of the mining operation - hence, the determination of the measures of their impacts is usually somewhat subjective, while the estimation of the mining damage based on deterministic methods is often insufficient. It is difficult to show the correlation between the local maximum of the impact of the velocity vector amplitude and the damage to the building - especially if the measures of interaction are not additive. The parameters of these impacts, as registered by measurements, form finite sets with a highly random character. Formally, it is adequate to the mapping from the probability space to the power set. For the purposes of the present study, the Dempster - Shafer model was used, where space is characterised by subadditive and superadditive measures. Regarding the application layer, the conclusions from the expert evaluations are assumed to be the values of random variables. The model was defined, and the risk of damage occurrence was estimated.

  18. Diversity of endolithic fungal communities in dolomite and limestone rocks from Nanjiang Canyon in Guizhou karst area, China.

    Science.gov (United States)

    Tang, Yuan; Lian, Bin

    2012-06-01

    The endolithic environment, the tiny pores and cracks in rocks, buffer microbial communities from a number of physical stresses, such as desiccation, rapid temperature variations, and UV radiation. Considerable knowledge has been acquired about the diversity of microorganisms in these ecosystems, but few culture-independent studies have been carried out on the diversity of fungi to date. Scanning electron microscopy of carbonate rock fragments has revealed that the rock samples contain certain kinds of filamentous fungi. We evaluated endolithic fungal communities from bare dolomite and limestone rocks collected from Nanjiang Canyon (a typical karst canyon in China) using culture-independent methods. Results showed that Ascomycota was absolutely dominant both in the dolomite and limestone fungal clone libraries. Basidiomycota and other eukaryotic groups (Bryophyta and Chlorophyta) were only detected occasionally or at low frequencies. The most common genus in the investigated carbonate rocks was Verrucaria. Some other lichen-forming fungi (e.g., Caloplaca, Exophiala, and Botryolepraria), Aspergillus, and Penicillium were also identified from the rock samples. The results provide a cross-section of the endolithic fungal communities in carbonate rocks and help us understand more about the role of microbes (fungi and other rock-inhabiting microorganisms) in rock weathering and pedogenesis.

  19. Experimental observation and modelling of rock - water interaction in a landslide-prone loess area of Hungary

    Science.gov (United States)

    Udvardi, Beatrix; Szabó, Zsuzsanna; Freiler, Ágnes; Kónya, Péter; Jerabek, Csaba; Pálfi, Éva; Kovács, István; Nagy, Péter; Halupka, Gábor

    2017-04-01

    It is well known that water from precipitation or other sources (e.g. groundwater, river) contributes to the triggering of landslides by means of infiltration into the slope, which causes an increase in the pore pressure and a reduction in the strength of the involved material. The physical failure is commonly coupled with chemical changes in landslides due the fact that soluble components dissolve in the pore water and others precipitate during rock-water interaction. Thus the composition of sediments and water chemistry are used jointly as indicators of the development of landslides. Rock-water interaction, however, takes a long time, and depends on hydrology and geochemistry of the landslide area; therefore, many researchers have focused on numerical simulation and laboratory experiment for setting up a landslide early warning system. Since water chemistry can change over time in landslides due to the seasonal rainfall pattern, groundwater fluctuation and flood events, the intensity of rock-water interaction (e.g. dissolution, precipitation) may also vary. Thus, the physicochemical processes cannot be elucidated precisely without understanding both the solution evolution and the mineral alteration in landslides. From this aspect, field survey, mineralogical (XRD, FTIR, DTG) and chemical measurements (ICP-OES), and geochemical modelling (PHREEQC) were conducted in a landslide-prone loess area along the River Danube (Hungary). Water from the River Danube and three springs were sampled during four field campaigns at Kulcs over a year. Additionally, landslide deposits including sliding surface and secondary precipitations were collected at Kulcs and Dunaújváros. In combination with previous hydrochemical analyses of the area and average rainfall composition of Hungary, it is possible to model the kinetic dissolution and precipitation of minerals during rainfall events and flooding periods of the river. The chemistry of springs shows that the Mg-Ca-HCO3 facies with

  20. Physical properties and petrologic description of rock samples from an IOCG mineralized area in the northern Fennoscandian Shield, Sweden

    DEFF Research Database (Denmark)

    Sandrin, Alessandro; Edfelt, Å.; Waight, Tod Earle

    2009-01-01

    The Tjårrojåkka Fe-Cu prospect in northern Sweden is considered an example of a Fe-oxide Cu-Au (IOCG) deposit and is hosted in metamorphosed Paleoproterozoic volcanic and intrusive rocks. Rock samples from 24 outcrops were collected for petrophysical analysis (magnetic susceptibility, remanent...

  1. Rapid large- and site scale RPAS mission planning for remote sensing of rock falls and landslides in alpine areas

    Science.gov (United States)

    Gräupl, Thomas; Pschernig, Elias; Rokitansky, Carl-Herbert; Oleire-Oltmanns, Sebastian; Zobl, Fritz

    2014-05-01

    Since landslides and rock falls are complex phenomena involving a multitude of factors, current and historic surface data play besides geologic conditions and others an important role in analyzing hazard situation and efficient site-specific remediation actions. Especially in displacement acceleration phases which are frequently linked to bad weather conditions, data acquisition remains difficult. Therefore RPAS with their small ground sampling distance and correspondingly high resolution open up possibilities for surveying ground situations not only for visual inspection but also for geodetic data acquisition. Both, visual and geodetic data provide valuable information for geologists and related decision makers. Slides or rock falls in alpine areas pose special challenges due to mostly acute and unforeseen displacements on the one hand and geographic conditions of narrow valleys along with steep slopes on the other hand. Rapid RPAS mission planning and mission adaption for individual requirements according to different project stages (initial investigation, repeat measurements, identification of hazard zones for urgent remediation actions, etc.) is therefore of particular importance. Here we present a computer-simulation supported approach to RPAS mission planning taking the identified thematic and remote sensing targets, the relevant terrain and obstacle databases, legal restrictions, aircraft performance, sensor characteristics, and communication ranges into account in order to produce a safe and mission-optimized flight route. For the RPAS mission planning, we combine and adapt tools developed at University of Salzburg, namely a flight track generator taking into account a 3D-model of the earth surface with both, focus on large area coverage (e.g. Austria) and the highest available resolution (e.g. sub-meter for specific areas), available obstacle data bases for the mission area (e.g. cable car lines, power lines, buildings, slope stabilization constructions

  2. Exploration, Drilling and Development Operations in the Bottle Rock Area of the Geysers Steam Field, With New Geologic Insights and Models Defining Reservoir Parameters

    Energy Technology Data Exchange (ETDEWEB)

    Hebein, Jeffrey J.

    1983-12-15

    MCR Geothermal Corporation pioneered successful exploratiory drilling the Bottle Rock area of the Geysers Steam Field in 1976. The wellfield is characterized by a deep reservoir with varied flowrates, temperatures, pressures, and stem chemistries being quite acceptable. More detailed reservoir engineering tests will follow as production commences.

  3. Buckling analysis of super-long rock-socketed filling piles in soft soil area by element free Galerkin method

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In order to discuss the buckling stability of super-long rock-socketed filling piles widely used in bridge engineering in soft soil area such as Dongting Lake, the second stability type was adopted instead of traditional first type, and a newly invented numerical analysis method, i.e. the element-free Galerkin method (EFGM), was introduced to consider the non-concordant deformation and nonlinearity of the pile-soil interface. Then, based on the nonlinear elastic-ideal plastic pile-soil interface model, a nonlinear iterative algorithm was given to analyze the pile-soil interaction, and a program for buckling analysis of piles by the EFGM(PBAP-EFGM) and arc length method was worked out as well. The application results in an engineering example show that, the shape of pile top load-settlement curve obtained by the program agrees well with the measured one, of which the difference may be caused mainly by those uncertain factors such as possible initial defects of pile shaft and the eccentric loading during the test process.However, the calculated critical load is very close with the measured ultimate load of the test pile, and the corresponding relative error is only 5.6%, far better than the calculated values by linear and nonlinear incremental buckling analysis (with a greater relative error of 37.0% and 15.4% respectively), which also verifies the rationality and feasibility of the present method.

  4. 'Wopmay' Rock

    Science.gov (United States)

    2004-01-01

    This approximate true-color image taken by NASA's Mars Exploration Rover Opportunity shows an unusual, lumpy rock informally named 'Wopmay' on the lower slopes of 'Endurance Crater.' The rock was named after the Canadian bush pilot Wilfrid Reid 'Wop' May. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe the lumps in Wopmay may be related to cracking and alteration processes, possibly caused by exposure to water. The area between intersecting sets of cracks eroded in a way that created the lumpy appearance. Rover team members plan to drive Opportunity over to Wopmay for a closer look in coming sols. This image was taken by the rover's panoramic camera on sol 248 (Oct. 4, 2004), using its 750-, 530- and 480-nanometer filters.

  5. Use of the Scanning Electron Microscope to Develop Knowledge About the Geological Source Area in Rocks by Comparing Relative Intensities of X-ray Peaks

    Science.gov (United States)

    Patterson, Casey; Quarles, C. A.

    2001-10-01

    Use of the Scanning Electron Microscope to Develop Knowledge About the Geological Source Area in Rocks by Comparing Relative Intensities of X-ray Peaks PATTERSON, C., Department of Geology, Department of Physics, Texas Christian University, QUARLES, C.A., Department of Physics, Texas Christian University, Fort Worth, Texas The generation of characteristic X-rays by use of the Scanning Electron Microscope (SEM) allows scientists of all fields to determine the elemental makeup of a sample under study. Geologically, circumstances exist where the mineralogical makeup of a rock sample is too fine-grained to determine with a hand lens or optical microscope. Knowledge of the mineralogical composition of a rock sample reflects on the rock type at the source area. This can ultimately allow geologists to determine ancient environments of deposition, including climate, as well as establish ideas on spatial events in geologic history. The rock sample used in this experiment was a piece of the Barnett Shale, taken from a petroleum source rock core at Mitchell Energy well T.P. Sims 2, drilled in Wise County, Texas. Once the sample is placed under the SEM and X-ray measurements are taken, the spectrum is then analyzed to label characteristic peak energies and match it with an element. Then, a first-order correction can be made for the absorption of lower energy photons by the Be window into the detector, the Au plating on the Si crystal, and for the Si crystal itself. Finally, a second-order correction can be made for the K-shell ionization cross section of each element seen on the X-ray spectrum. The resulting number of counts in each peak, after both corrections, represents an overall bulk chemical composition of the sample. With this information, one can analyze the data and logically deduce the amount and type of minerals in the sample, which, in turn, will allow for conclusions about the source area.

  6. Petrogenesis of subvolcanic rocks from the Khunik prospecting area, south of Birjand, Iran: Geochemical, Sr-Nd isotopic and U-Pb zircon constraints

    Science.gov (United States)

    Samiee, Somayeh; Karimpour, Mohammad Hassan; Ghaderi, Majid; Haidarian Shahri, Mohammad Reza; Klöetzli, Urs; Santos, José Francisco

    2016-01-01

    The Khunik prospecting area is located 106 km south of Birjand in eastern Iran, and is considered as an epithermal gold prospecting area. The mineralization is related to subvolcanic rocks. There are several outcrops of subvolcanic intrusions in the area which intruded into Paleocene-Eocene volcanic rocks (andesite, trachy-andesite and pyroclastic rocks). Petrographic studies indicate that subvolcanic rocks consist mainly of diorite, monzonite, quartz-monzonite, monzodiorite and quartz-monzodiorite. Mineralogically, these rocks contain plagioclase, K-feldspar, amphibole, pyroxene, biotite and quartz. Geochemically, they have features typical of high-K calk-alkaline to shoshonitic and are metaluminous, and also belong to magnetite granitoid series (I-type). Primitive mantle normalized trace element spider diagrams display enrichment in LILE, such as Rb, Ba, and Cs, compared to HFSE. Chondrite-normalized REE plots show moderately LREE enriched patterns (7.45 < LaN/YbN < 10.54), and no significant Eu anomalies. Tectonic discrimination diagrams also show affinities with modern convergent margin magmas, suggesting that magmas of Khunik area formed in volcanic arc setting related to subduction of the oceanic crust under the Lut Block plate. The initial 87Sr/86Sr ratios (0.704196-0.704772) and εNdi values (+1.3 to +3.3) are compatible with an origin of the parental melts in a supra-subduction mantle wedge. Zircon U-Pb dating by LA-ICP-MS indicates the age of 38 ± 1 Ma (late Eocene) for subvolcanic units that are related to mineralization. A biotite granodiorite porphyry is the testimony of the youngest magmatic activity in the area, with an age of 31 ± 1 Ma (early Oligocene). The represented dates are interpreted as magmatic crystallization ages of subvolcanic intrusions.

  7. Chemical composition of fragmental products fractions of rock dumps and tailing dump as basis for potential geoecological danger estimation in the areas of mining enterprises

    Directory of Open Access Journals (Sweden)

    Vdovina Ol’ga Konstantinovna

    Full Text Available Negative consequences of deposit development on the environment are well know. They manifest themselves most intensively in case of open-cut mining of ore minerals, which is related to the increase of rock dumps masses. The material of rock dumps and tailing dumps actively influence the state of the environment transforming the natural landscapes, first of all, as a reason of migration of waters changed as a result of their contact with mining waste. The authors give their estimation of the consequences of apatite-nephelinic ore crop in Khibini Ore District by the company “Apatit”, which includes the influence on the natural waters. The unique natural conditions of the area are the reason for high-level potential geoecological danger. The mobility of lots of toxic elements is raised because of ligand-ion OH in the waters of alkali rocks of Khibini soil.

  8. Unioned layer for the Point of Rocks-Black Butte coal assessment area, Green River Basin, Wyoming (porbbfing.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This ArcView shapefile contains a polygon representation of the spatial query layer for the Point of Rocks-Black Butte coalfield, Greater Green River Basin, Wyoming....

  9. Petrogenesis of Cretaceous adakitic and shoshonitic igneous rocks in the Luzong area, Anhui Province (eastern China): Implications for geodynamics and Cu Au mineralization

    Science.gov (United States)

    Wang, Qiang; Wyman, Derek A.; Xu, Ji-Feng; Zhao, Zhen-Hua; Jian, Ping; Xiong, Xiao-Lin; Bao, Zhi-Wei; Li, Chao-Feng; Bai, Zheng-Hua

    2006-07-01

    Both adakitic and shoshonitic igneous rocks in the Luzong area, Anhui Province, eastern China are associated with Cretaceous Cu-Au mineralization. The Shaxi quartz diorite porphyrites exhibit adakite-like geochemical features, such as light rare earth element (LREE) enrichment, heavy REE (HREE) depletion, high Al 2O 3, MgO, Sr, Sr / Y and La / Yb values, and low Y and Yb contents. They have low ɛNd( t) values (- 3.46 to - 6.28) and high ( 87Sr / 86Sr) i ratios (0.7051-0.7057). Sensitive High-Resolution Ion Microprobe (SHRIMP) zircon analyses indicate a crystallization age of 136 ± 3 Ma for the adakitic rocks. Most volcanic rocks and the majority of monzonites and syenites in the Luzong area are K-rich (or shoshonitic) and were also produced during the Cretaceous (140-125 Ma). They are enriched in LREE and large-ion lithophile elements, and depleted in Ti, and Nb and Ba and exhibit relatively lower ɛNd( t) values ranging from - 4.65 to - 7.03 and relatively higher ( 87Sr / 86Sr) i ratios varying between 0.7057 and 0.7062. The shoshonitic and adakitic rocks in the Luzong area have similar Pb isotopic compositions ( 206Pb / 204Pb = 17.90-18.83, 207Pb / 204Pb = 15.45-15.62 and 208Pb / 204Pb = 38.07-38.80). Geological data from the Luzong area suggest that the Cretaceous igneous rocks are distributed along NE fault zones (e.g., Tanlu and Yangtze River fault zones) in eastern China and were likely formed in an extensional setting within the Yangtze Block. The Shaxi adakitic rocks were probably derived by the partial melting of delaminated lower crust at pressures equivalent to crustal thickness of > 50 km (i.e., ˜1.5 GPa), possibly leaving rutile-bearing eclogitic residue. The shoshonitic magmas, in contrast, originated mainly from an enriched mantle metasomatized by subducted oceanic sediments. They underwent early high-pressure (> 1.5 GPa) fractional crystallization at the boundary between thickened (> 50 km) lower crust and lithospheric mantle and late low

  10. [Micro-area characteristics of laminated chert in the volcanic rocks of Xionger Group of Ruyang area and its geological significances].

    Science.gov (United States)

    Luo, An; Li, Hong-zhong; Zhao, Ming-zhen; Yang, Zhi-jun; Liang, Jin; He, Jun-guo

    2014-12-01

    The Xionger Group was originated from the volcanic eruption and sedimentation in Precambrian, whose sedimentary strata at the top were named Majiahe Formation. In the Majiahe Formation, there were hydrothermal chert widely distributed, which were exhibited to be interlayers in the volcanic rocks. The polarized microscope, X-ray diffraction (XRD), Raman and electron back scatter diffraction (EBSD) were conducted to study the characteristics in micro area of the jasperite samples, which were from the sedimentary interlayers in the volcanic rocks of Majiahe Formation in Xionger Group. As shown in the microphotographs and EBSD images, the quartz in the chert had small grain size, low degree of crystallinity and close packed structure, which quite agreed with the characteristics of hydrothermal sedimentary chert. In the chert of Xionger Group, there were clear banded (or lamellar) structures which were contributed by the diversities of the grain size and mineral composition. The different bands (or lamellars) had alternative appearance repeatedly, and denoted the diversities and periodic changes in the substance supply during the precipitation. According to the results of the XRD analysis, the majority minerals of the chert was low temperature quartz, whose lattice parameters were a=b=0.4913 nm, c=0.5405 nm and Z=3. As denoted in the EBSD image and result of Raman analysis, several impurity minerals were formed in the chert in different stages, whose geneses and formation time were quite different. The clay minerals and pyrite were scattered in distribution, and should be contributed by the original sedimentation. On contrary, the felsic minerals and mafic silicate minerals were originated from the sedimentation of tuffaceous substance during the volcanic eruption. The minerals of volcanic genesis had relatively larger grain size, and they deposited together with the hydrothermal sediments to form the bands (or lamellars) of coarse minerals. However, the hydrothermal

  11. Deep-derived enclaves (belonging to middle-lower crust metamorphic rocks) in the Liuhe-Xiangduo area,eastern Tibet: Evidence from petrogeochemistry

    Institute of Scientific and Technical Information of China (English)

    WEI Qirong; LI Dewei; ZHENG Jianping; WANG Jianghai

    2006-01-01

    Petrological and geochemical studies of deep-derived enclaves from the Liuhe-Xiangduo area, eastern Tibet, showed that the enclaves involve five types of rocks, i. e. , garnet diopsidite, garnet amphibolite, garnet hornblendite, amphibolite and hornblendite, whose main mineral assemblages are Grt+Di + Hbl, Grt+ Pl + Hbl + Di, Grt + Hbl + Pl, Pl + Hbl, and Hbl + Bt, respectively. The enclaves exhibit typical crystalloblastic texture, and growth zones are well developed in garnet (Grt) in the enclaves. In view of major element geochemistry, the deep-derived enclaves are characterized by high MgO and FeO * ,ranging from 12.00% to 12.30% and 8.15% to 10.94%, respectively. The protolith restoration of metamorphic rocks revealed that the enclaves belong to ortho-metamorphic rocks. The REE abundances vary over a wide range, and ∑ REE ranges from 53.39 to 129.04 μg/g. The REE patterns slightly incline toward the HREE side with weak LREE enrichment. The contents of Rb, Sr, and Ba range from 8.34 to 101μg/g, 165 to 1485 μg/g, and 105 to 721 μg/g, respectively. The primitive mantle-normalized spider diagrams of trace elements show obvious negative Nb, Ta, Zr and Hf anomalies. Sr-Nd isotopic compositions of the enclaves indicated that the potential source of deep-derived enclaves is similar to the depletedmantle, and their (87Sr/86Sr) i ratios vary from 0.706314 to 0.707198, (147Nd/144Nd)i ratios from 0.512947 to 0.513046, and εNd(T) values from + 7.0 to +9.0, respectively. The potential source of the enclaves is obviously different from the EM2-type mantle from which high-K igneous rocks stemmed(the host rocks), i.e. , there is no direct genetic relationship between the enclaves and the host rocks.Deep-derived enclaves in the host rocks belong to mafic xenoliths, and those in the Liuhe-Xiangduo area,eastern Tibet, are some middle-lower crust ortho-metamorphic rocks which were accidentally captured at20-50 km level by rapidly entrained high-temperature high-K magma

  12. Investigating the impact of global climatic and landuse changes on groundwater resources in hard rock areas of South India

    Science.gov (United States)

    Ferrant, S.; Perrin, J.; Marechal, J.; Dewandel, B.; Aulong, S.; Ahmed, S.

    2010-12-01

    In most parts of India, and particularly in South India, groundwater levels are hazardously declining, while agricultural groundwater use is increasing. The current issue is to address the probable evolution of water table levels in relation with climate and agricultural changes. The aim of the SHIVA-ANR project (http://www.shiva-anr.org) is to provide some indicators of the water availability at the village scale to evaluate the vulnerability of farmers facing global changes. This study focuses on a particularly water stressed semi-arid area of South India characterized by hard rock geology with naturally low recharge capacity and limited surface water availability. The study catchment is located in the agricultural area of the Kudaliar river watershed (980km^2) located 50 km north of Hyderabad, India. It is composed of about 120 villages. Socio economic surveys have been carried out at the village scale to evaluate the present socio-economic situation of farmers. It also provides more details on various cultural and irrigation practices at this scale. The landuse has been evaluated by remote sensing with two satellite images, one after monsoon (October 2009), and the other during dry season (March 2010). Groundwater-irrigated rice paddies represent about 10% of the area, whereas rainfed crop (corn and cotton) represent about 45%. Numerous small tanks (reservoir) situated on the river network define a water harvesting system of 2% of the catchment area which captures surface runoff during monsoon. No discharges data are available at the outlet, as the river is dry most of the year. A hydro-geological survey has been carried out to provide a map of aquifer thickness and the general state of the groundwater level before and after monsoon. The Soil Water Assessment Tool model (SWAT) has been calibrated to assess the water budget of the agricultural catchment under present conditions. Soil parameters calibration is made first on seasonal groundwater recharge for

  13. SIR 2014-5076, Land-Cover Data for Red Rock Canyon National Conservation Area and Coyote Springs, Piute-Eldorado Valley, and Mormon Mesa Areas of Critical Environmental Concern, Clark County, Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Four polygon vector data sets and one related table describe land-cover in Red Rock Canyon National Conservation Area (RRC_NCA_p) and Coyote Springs (CS_ACEC_p),...

  14. Geochronology and geochemistry of Eocene-aged volcanic rocks around the Bafra (Samsun, N Turkey) area: Constraints for the interaction of lithospheric mantle and crustal melts

    Science.gov (United States)

    Temizel, İrfan; Arslan, Mehmet; Yücel, Cem; Abdioğlu, Emel; Ruffet, Gilles

    2016-08-01

    40Ar-39Ar age, whole-rock chemical, and Sr-Nd isotope data are presented for the post-collisional, Eocene (51.3-44.1 Ma)-aged volcanic rocks from the Bafra (Samsun) area in the western part of the Eastern Pontides (N Turkey) aiming to unravel their sources and evolutionary history. The studied Eocene volcanic rocks can be divided into two groups: analcime-bearing (tephritic lava flows and dykes) and analcime-free (basaltic to trachytic lava flows and basaltic dykes). The analcime-bearing volcanic rocks have a fine-grained porphyritic texture with clinopyroxene phenocrysts, whereas analcime-free volcanic rocks show a variety of textures including hyalo-microlitic microgranular porphyritic, intersertal, trachytic, fluidal, and glomeroporphyritic. The volcanic rocks also show evidence of mineral-melt disequilibrium textures such as sieved, rounded, and corroded plagioclases, partially melted and dissolved clinopyroxenes and poikilitic texture. Petrochemically, the parental magmas of the volcanic rocks evolved from alkaline to calc-alkaline lava suites and include high-K and shoshonitic compositions. They display enrichments in light rare earth and large ion lithophile elements such as Sr, K, and Rb, as well as depletions in high field strength elements such as Nb, Ta, Zr, and Ti, resembling subduction-related magmas. The analcime-bearing and -free volcanic rocks share similar incompatible element ratios and chondrite-normalised rare rearth element patterns, indicating that they originated from similar sources. They also have relatively low to moderate initial 87Sr/86Sr (0.7042-0.7051), high positive εNd(t) values (+ 0.20 to + 3.32), and depleted mantle Nd model ages (TDM1 = 0.63-0.93 Ga, TDM2 = 0.58-0.84 Ga). The bulk-rock chemical and Sr-Nd isotope features as well as the high Rb/Y and Th/Zr, but low Nb/Zr and Nb/Y ratios, indicate that the volcanic rocks were derived from a lithospheric mantle source that had been metasomatised by slab-derived fluids. Trace element

  15. Silica- and sulfate-bearing rock coatings in smelter areas: Products of chemical weathering and atmospheric pollution I. Formation and mineralogical composition

    Science.gov (United States)

    Mantha, Nathalie M.; Schindler, Michael; Murayama, Mitsuhiro; Hochella, Michael F.

    2012-05-01

    Black rock-coatings occur in proximity to smelters and roast yards of the Greater Sudbury area, Ontario, Canada and contain information about the past interactions between surface minerals, and gaseous and particulate atmospheric components, many of which were pollutants. Rock-coatings were collected from various locations within the Sudbury area and are characterized with scanning electron microscopy, transmission electron microscopy, X-ray diffraction, electron microprobe analysis, infrared spectroscopy and X-ray photoelectron spectroscopy. Acidic fumigations and rain, the result of vast quantities of SO2 released from smelting, increased the chemical weathering rate of exposed rocks in the Sudbury area. Non-stoichiometric dissolution of the silicate minerals under acidic conditions resulted in the accumulation of silicic acid and the subsequent formation of a silica-gel type coating. The silica gel transformed overtime into amorphous silica, opal (opal C and opal-CT) and cristobalite. Dissolution of the underlying rock and also of metal-bearing particles by sulfuric acid resulted in the in situ formation of metal-sulfate-rich layers on the interfaces between the atmosphere and the silica-rich coating (atmosphere-coating interface, ACI) and between the silica-rich coating and the underlying rock (rock-coating interface, RCI). These metal-sulfate-rich layers contain nanometer aggregates of Fe-Cu-sulfate-hydroxide, goldichite, mereiterite, guildite, butlerite and antlerite. The silica-rich matrix also contains a mix of detrital grains from adjacent rocks and soils (feldspar, quartz, hematite, chlorite, montmorillonite) and non-dissolved smelter-derived nano- to micro-size particulates (metal-silicates, metal-oxides, C-spheres). The apparent disequilibrium between the embedded particles and the Fe-Cu-sulfates suggests that trapped nanoparticles were encapsulated into pores which prevented their equilibration with acidic metal-sulfate-bearing fluids. An XPS depth

  16. Techniques for the Construction of Tunnels in Areas of Strong Rock Burst%强岩爆隧道施工技术

    Institute of Scientific and Technical Information of China (English)

    李方利

    2012-01-01

    The embedded depth of the 3# auxiliary tunnel of the Jinping Power Station is more than 2,200m,with very high in-situ stress.The tunnel is located in an area of strong rock burst.The microseismic monitoring method of rock burst is used for the prediction of rock burst in the process of construction,with the techniques of spraying high-pressure water and injecting water deep into the body of rocks,smooth-face blasting,stress-relieving blasting and timely providing anchor bolts,shotcreting supporting concrete,etc.adopted in collaboration.The above-mentioned techniques and measures help greatly reduce the probability of rock burst and the risks of serious consequences of rock burst,and ensure the successful completion of the excavation of the tunnel.%锦屏电站辅引3#隧洞埋深超过2 200m,地应力极高,属于强岩爆洞段。施工中采用微震监测方法进行岩爆预测,结合喷洒高压水和岩体深部注水技术、光面爆破及应力解除爆破技术和及时施作锚杆、喷砼等支护措施,大大降低岩爆发生概率和产生严重后果的风险,顺利完成隧洞的开挖施工。

  17. Geology and geochemistry of palaeoproterozoic low-grade metabasic volcanic rocks from Salumber area, Aravalli Supergroup, NW India

    Indian Academy of Sciences (India)

    L S Shekhawat; M K Pandit; D W Joshi

    2007-12-01

    The Palaeoproterozoic Aravalli Supergroup in Salumber region includes a basal unit of metabasic volcanic rocks (Salumber volcanic rocks) overlain by a volcaniclastic/conglomerate one. Although these volcanic rocks have been metamorphosed to green-schist facies, some primary volcanic features are still preserved. This metabasic volcanic sequence can be further differentiated on the basis of textural variations, and the mineral assemblages are: (a) oligoclase + actinolite + chlorite + epidote; and (b) oligoclase + hornblende+ chlorite + biotite + Fe-Ti oxides. The SiO2 content ranges from ∼47.7 to 55.8% and MgO from ∼4.2 to 12.8%. Geochemical characteristics allow their subdivision into high Mg and Fe tholeiites. Inverse relationship of MgO with silica, alkalis and Zr is generally consistent with fractionation mechanism, also suggested by a change in colour of the rocks from dark greenish to light greenish towards the upper parts of the sequence. These metabasic volcanic rocks are enriched in incompatible trace elements and LREE (La = 30 − 40 × chondrite, Lu = 2 − 5 × chondrite), and demonstrate affinity mainly with MORB and within plate settings in geochemical tectonic discrimination schemes. The geochemical characteristics suggest a complex evolutionary history envisaging derivation of the melt from an enriched heterogeneous lithospheric source.

  18. Forecasting the degree of rock burst hazard in areas of gas bearing coal seams by the electromagnetic radiation method

    Energy Technology Data Exchange (ETDEWEB)

    Proskuryakov, V.M.; Shabarov, A.N.; Frid, V.I. (Vsesoyuznyi Nauchno-Issledovatel' skii Institut Gornoi Geomekhaniki i Marksheiderskogo Dela (USSR))

    1991-02-01

    Presents results of investigations into emission of electromagnetic waves in zones of increased rock burst hazard conducted during drivage of a ventilation gallery in the Anzherskaya mine (Severokuzbassugol' association). Relationships between the emission of electromagnetic impulses, yield of drilling, gas yield rate, the distance between increased stress zones and seam denudation and time are discussed and presented in diagrams. Regularities of variation in electromagnetic radiation at various stress states in coal seam boundary parts with the gas yield factor taken into account were found. Suitability of recording electromagnetic radiation for forecasting rock burst hazards was shown and criteria for evaluating the degree of rock burst hazard for a coal seam in the Anzherskaya mine are presented. 3 refs.

  19. Geochronological Significance of the Post-Orogenic Mafic-Ultramafic Rocks in the Hongqiling Area of Jilin Province, Northeast China

    Institute of Scientific and Technical Information of China (English)

    Zhang Guangliang; Wu Fuyuan

    2006-01-01

    Mafic-ultramafic complexes are widespread in Hongqiling in central Jinlin Province, NE China. The Hongqiling complex comprises pyroxenite, olivine websterite, lherzolite, gabbro and leucogabbro. Based on the latest geochronological results, these intrusions yield a zircon U-Pb age of about 216 Ma, implying that they emplaced in the late Triassic period and that the mafic-ultramafic complexes are post-orogenic in origin. These ages are coeval with the emplacement of A-type granites in the area, but slightly younger than syn-orogenic granitic magmatism. The composition of the parent magma during the equilibration of the accumulated olivine crystallizing is basaltic with high MgO, and it comes from depleted or juvenile lithospheric mantle, according to the results of trace elements and Sr-Nd isotopes. Amount of crustal material contaminated the magmatic source, implying that the mafic-ultramafic rocks originate from the mixing product of crust- and mantle-derived magma. Therefore, the magmatic source was contaminated by an amount of crustal material, and the subsequent crystal fractionation resulted in the Cu-Ni mineralization. Dynamic analyses indicate that, after the collision of the North China Craton and Jiamusi Massif, the lithospheric delamination during post-orogeny resulted in the upwelling of asthenosphere and the intruding of the mass and underplating of the mantle-derived magma, which led to the formation of the primary mafic-ultramafic magma due to the mantle-derived magma and partial melting of the lower crust. This result suggests that the mafic-ultramafic complexes belong to a typically important magmatic suite that evolved during post-orogenic processes, and they were exposed as maficultramafic dyke swarms that existed in the post-orogenic extension environment. It also implies that the orogenic process finished ultimately in this regional geological setting. The widespread occurrence of mafic-ultramafic complexes in the Xing'an-Mongolia Orogenic Belt

  20. Geologic framework of pre-Cretaceous rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico

    Science.gov (United States)

    Condon, Steven M.

    1992-01-01

    This report is a discussion and summary of Jurassic and older rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico, and is based on analysis of geophysical logs and observations of outcrops. The Reservation, which is located in the northern San Juan Basin, has been the site of deposition of sediments for much of the Phanerozoic. Geologic times represented on the Reservation are the Precambrian, Cambrian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary, and Quaternary. Rocks of Ordovician and Silurian age have not been reported in this region. Thicknesses of pre-Cretaceous sedimentary rocks range from about 750 feet (229 meters) on the Archuleta arch, east of the Reservation, to more than 8,300 feet (2,530 meters) just northwest of the Reservation. About 5,500 feet (1,676 meters) of pre-Cretaceous sedimentary rocks occur in the central part of the Reservation, near Ignacio. At Ignacio the top of the Jurassic lies at a depth of 7,600 feet (2,316 meters) below the surface, which is composed of Tertiary rocks. As much as 2,500 feet (762 meters) of Tertiary rocks occur in the area. More than 10,000 feet (3,048 meters) of Cretaceous and younger rocks, and 15,600 feet (4,755 meters) of all Phanerozoic sedimentary rocks occur in the vicinity of the Reservation. In the early Paleozoic the area that includes the Southern Ute Reservation was on the stable western shelf of the craton. During this time sediments that compose the following shallow-marine clastic and carbonate rocks were deposited: the Upper Cambrian Ignacio Quartzite (0-150 feet; 0-46 meters), Upper Devonian Elbert Formation (50-200 feet; 15-61 meters), Upper Devonian Ouray Limestone (10-75 feet; 3-23 meters), and Mississippian Leadville Limestone (0-250 feet; 0-76 meters). Mixed carbonate and clastic deposition, which was punctuated by a unique episode of deposition of evaporite sediments, continued through

  1. 广域岩土体变化监测研究%Study on monitoring of rock and soil change in a large area

    Institute of Scientific and Technical Information of China (English)

    谢谟文; 黄洁慧; 王增幅; 刘翔宇

    2012-01-01

    Conventional methods of monitoring change in rock and soil are difficult to be used to implement continuous monitoring of ground deformation in large-size reservoir and its surrounding areas. In order to solve the key problem of monitoring the real-time change in rock and soil in the reservoir area of large scale hydropower station, the reservoir area of Wudongde hydropower station was selected as the study area. According to change types of rock and soil, D-InSAR technique and false color composite technology were used to monitor changes respectively, and changing region was extracted finally. Comparing the results derived from two methods with that of field investigation, the deformation locations of rock and soil as well as its trends are in agreement. It meets the monitoring purpose including discovering change and monitoring trend. It is proved that the combined method of D-InSAR technology and false color composite technology is feasible to monitor the wide-area change in rock and soil.%常规岩土体变化监测方法的局限性造成采用它们来实施大型库区及周边地表形变的持续监测非常困难.为了解决大型水电站库区岩土体的高效实时变化监测这一关键问题,选取乌东德水电站库区为研究区域,根据岩土体变化类型,分别采用D-InSAR技术和假彩色合成技术对库区进行监测,提取出变动区域.最后通过2种方法的监测结果与地面验证结果的比较,验证了变化地点和岩土变动类型与分析结果相一致,达到了发现变化、监视趋势的遥感监测目的.证明了D-InSAR技术和假彩色合成技术相结合用于监测广域岩土体变化的可行性.

  2. Geochronology, geochemistry, and Sr-Nd-Hf isotopes of the early Paleozoic igneous rocks in the Duobaoshan area, NE China, and their geological significance

    Science.gov (United States)

    Wu, Guang; Chen, Yuchuan; Sun, Fengyue; Liu, Jun; Wang, Guorui; Xu, Bei

    2015-01-01

    The Duobaoshan area of northwestern Heilongjiang Province is the most important copper resource concentration region in NE China. To date, the Duobaoshan superlarge Cu-Mo deposit and the Tongshan large Cu-Mo deposit have been discovered in the Duobaoshan area. Both the deposits are hosted by granodiorites and volcanic rocks. Zircon LA-ICP-MS U-Pb dating indicates that these granodiorites emplaced approximately 479 Ma ago and that those volcanic rocks erupted between 447 and 450 Ma. The early Ordovicain granodiorites belong to the high-K to medium-K calc-alkaline series and are characterized by high Al2O3 and Sr contents, low Yb and Y contents, and relatively low Mg# values and Na2O/K2O ratios, with positive Eu or slight negative Eu anomalies (averaging 1.18). All of these geochemical characters are similar to those of the adakites generated by partial melting of a thickened lower crust in the world. Moreover, the granodiorites have low initial 87Sr/86Sr ratios (varying from 0.703474 to 0.704436), very high zircon εHf(t) and whole-rock εNd(t) values (varying from 13.0 to 16.8 and 5.27 to 5.46, respectively), and young zircon Hf and whole-rock Nd single-stage and two-stage model ages. Taking these geochemical characteristics and Sr-Nd-Hf isotope compositions together, we suggest that the early Ordovician granodiorites in the Duobaoshan area occurred in a post-collision environment and were formed by partial melting of a juvenile thickened lower crust dominated by depleted mantle-derived material. These late Ordovician volcanic rocks, which are composed of basalt, basaltic andesite, and andesite, belong to the tholeiitic or calc-alkaline series. They are generally enriched in large ion lithophile elements (LILEs) and depleted in high field strength elements (HFSEs; e.g., Nb, Ta, Zr, Hf, P, and Ti), consistent with the geochemistry of igneous rocks from island arcs or active continental margins. Compared with the early Ordovician granodiorites, these volcanic rocks

  3. Geochronology and geochemistry of a suite of mafic rocks in Chencai area, South China: Implications for petrogenesis and tectonic setting

    Science.gov (United States)

    Zhao, Lei; Zhai, Mingguo; Zhou, Xiwen; Santosh, M.; Ma, Xudong

    2015-11-01

    Paleozoic crust-mantle interaction and geodynamic setting of the South China Block have remained largely elusive due to the scarcity of mafic rock suites. Here we report data from a suite of mafic rocks including norite, mafic granulite, garnet-bearing amphibolite, biotite-bearing amphibolite, and amphibolite from the Chencai region in the northeastern Cathaysia Block of South China, that mostly record amphibolite to granulite facies metamorphism. U-Pb dating of zircons from the mafic granulite and biotite-bearing amphibolite show broadly coeval magmatism, and amphibolite- to granulite-facies metamorphism during 435-438 Ma. The garnet-bearing amphibolite also records metamorphism at 436 Ma and the magmatic age of its protolith is constrained to be between 436 Ma and 496 Ma. The norite has an emplacement age of 422 Ma. Geochemically, the amphibolite and granulite have high Al2O3 contents and belong to the high-alumina group. The garnet-bearing amphibolite belongs to the intermediate-alumina group, whereas the norite and biotite-bearing amphibolite belong to the low-alumina group. A cumulate origin is proposed for the norite with orthopyroxene as the main cumulus phase. Based on their similar trace element and Lu-Hf isotopic signatures, it is inferred that the protoliths of amphibolite and granulite belonging to high-alumina group were likely generated from the same source. Furthermore, their LREE enrichment relative to HREE, positive Eu anomaly, and negative Nb, Ta and Zr anomalies suggest derivation from the same enriched mantle source, perhaps in a continental arc environment. Zircons from the garnet-bearing amphibolite belonging to intermediate-alumina group have high positive ɛHf (t) values with a peak of + 14 and trace element signatures similar to N-MORB, suggesting a depleted asthenospheric mantle source. The rock suite from Chencai suggests formation in an active continental margin, with the garnet-bearing amphibolite representing relics of the Paleozoic

  4. Summary of Synoptic Meteorological Observations (SSMO). South America and Selected Island Coastal Marine Areas, Atlantic Islands. Volume 3. Area 17 - Tierra del Fuego, Area 18 - Falkland Islands, Area 19 -South Georgia, Area 20 - Tristan da Cunha Group, Area 21 - Trindade, Area 22 - St. Helena, Area 23 - Ascension, Area 24 - St. Peter and Paul Rocks

    Science.gov (United States)

    1977-06-01

    0 17.5 .0 .0 .0 .0 .0 .0 .0 FACE »21 »TW* ■■’■ "■ IIUI" »E«ICD! fOVE«-«LO 1963-1970 JANUARY TABLE 18 (CONTi IKEA 0021 TOINDADE...DIRECTION VIPSuS SE4 HEIGHTS IFTl IKEA 0024 ST, PETER AND PAUL ROCKS ,6N 29.3» s iu HGT 1-3 4-10 11-21 22-33 34-47 41« PCT 1...l". - L ■■■’■■’ • ’ " wwm PEIKOl iQVER-»LLI IS’OS-l1»?» I SFPTEMBfR TABLE 16 (CDNT1 IKEA 002« ST. PETER AND PAUL RCfKS

  5. Detailed geomorphological mapping of debris-covered and rock glaciers in the Hólar area, Tröllaskagi Peninsula (northern Iceland).

    Science.gov (United States)

    Tanarro, Luis M.; Palacios, David; Zamorano, Jose J.; Andres, Nuria

    2017-04-01

    Most studies conducted on rock and debris-covered glaciers only include simplified geomorphological maps representing main units (ridges, furrows, front, and thermokarst depressions). The aim of this study is to develop a detailed geomorphological mapping of the Hóladalsjökull debris-covered glacier (65°42' N; 18°57' W) and the Fremri-Grjótárdalur rock glacier (65°43' N 19° W), located near Hólar, a village in the central area of the Trolläskagi peninsula (northern Iceland). The mapping process has been conducted using standard stereo-photointerpretation of aerial photographs and stereo-plotting of a topographic map at 1:2000 scale. Also, landforms have been represented in different transects. Lastly, the geomorphological map has been designed using the elevation digital model, and a 3D pdf file has been generated, allowing for better viewing and understanding the different units and their modelling. The geomorphological mapping of the Hóladalsjökull debris-covered glacier and the Fremri-Grjótárdalur rock glacier represents the prominent walls of their valley heads and their summits, which form a flat highland at 1,200-1,330 metres above sea level, covered by blockfield and patterned ground features. Rockfall and slide landforms are common processes at the foot of these 100-170 metre-high cirque-walls. Debris-covered glaciers and rock glaciers are born right under these walls, building up a spoon-shaped hollow around glacial ice, surrounded by young moraine ridges at their fronts. The dominant features in the Hóladalsjökull debris-covered glacier are large longitudinal ridges and furrows, stretching over 1.5 km in length in the central and western areas. Medium-sized thermokarst depressions (between 15-40 metres in diameter), often running parallel to the furrows, dot the surface of the debris-covered glacier. Parallel alternate ridges and furrows can be seen near the snout. Ridges are rugged and fall around 30-40 metres, with over 30 degree slopes

  6. Sequence Stratigraphy and Sedimentary Facies of Lower Oligocene Yacheng Formation in Deepwater Area of Qiongdongnan Basin, Northern South China Sea:Implications for Coal-Bearing Source Rocks

    Institute of Scientific and Technical Information of China (English)

    Jinfeng Ren; Hua Wang; Ming Sun; Huajun Gan; Guangzeng Song; Zhipeng Sun

    2014-01-01

    For unveiling coal-bearing source rocks in terrestrial-marine transitional sequences, the sequence stratigraphic framework and sedimentary facies of Lower Oligocene Yacheng Formation of Qiongdongnan Basin were investigated using seismic profiles, complemented by well bores and cores. Three third-order sequences are identified on the basis of unconformities on basin margins and cor-relative conformities in the basin center, namely SQYC3, SQYC2 and SQYC1 from bottom to top. Coal measure in Yacheng Formation of Qiongdongnan Basin were deposited within a range of facies asso-ciations from delta plain/tidal zone to neritic sea, and three types of favourable sedimentary facies as-sociations for coal measure were established within the sequence stratigraphic framework, including braided delta plain and alluvial fan, lagoon and tidal flat, and fan delta and coastal plain facies associa-tions. Results shown that, in the third-order sequences, coal accumulation in landward areas (such as delta plain) of the study area predominantly correlates with the early transgressive systems tract (TST) to middle highstand systems tract (HST), while in seaward areas (such as tidal flat-lagoon) it correlates with the early TST and middle HST. The most potential coal-bearing source rocks formed where the accommodation creation rate (Ra) and the peat-accumulation rate (Rp) could reach a state of balance, which varied among different sedimentary settings. Furthermore, intense tectonic subsidence and fre-quent alternative marine-continental changes of Yacheng Formation during the middle rift stage were the main reasons why the coal beds shown the characteristics of multi-beds, thin single-bed, and rapidly lateral changes. The proposed sedimentary facies associations may aid in predicting distribution of coal-bearing source rocks. This study also demonstrates that controlling factors analysis using sequence stratigraphy and sedimentology may serve as an effective approach for coal

  7. Water Resources of the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah - Draft Report

    Science.gov (United States)

    Welch, Alan H.; Bright, Daniel J.

    2007-01-01

    Summary of Major Findings This report summarizes results of a water-resources study for White Pine County, Nevada, and adjacent areas in east-central Nevada and western Utah. The Basin and Range carbonate-rock aquifer system (BARCAS) study was initiated in December 2004 through Federal legislation (Section 131 of the Lincoln County Conservation, Recreation, and Development Act of 2004) directing the Secretary of the Interior to complete a water-resources study through the U.S. Geological Survey, Desert Research Institute, and State of Utah. The study was designed as a regional water-resource assessment, with particular emphasis on summarizing the hydrogeologic framework and hydrologic processes that influence ground-water resources. The study area includes 13 hydrographic areas that cover most of White Pine County; in this report however, results for the northern and central parts of Little Smoky Valley were combined and presented as one hydrographic area. Hydrographic areas are the basic geographic units used by the State of Nevada and Utah and local agencies for water-resource planning and management, and are commonly defined on the basis of surface-water drainage areas. Hydrographic areas were further divided into subbasins that are separated by areas where bedrock is at or near the land surface. Subbasins represent subdivisions used in this study for estimating recharge, discharge, and water budget. Hydrographic areas represent the subdivision used for reporting summed and tabulated subbasin estimates.

  8. Water Resources of the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah

    Science.gov (United States)

    Welch, Alan H.; Bright, Daniel J.; Knochenmus, Lari A.

    2008-01-01

    INTRODUCTION This report summarizes results of a water-resources study for White Pine County, Nevada, and adjacent areas in east-central Nevada and western Utah. The Basin and Range carbonate-rock aquifer system (BARCAS) study was initiated in December 2004 through Federal legislation (Section 301(e) of the Lincoln County Conservation, Recreation, and Development Act of 2004; PL108-424) directing the Secretary of the Interior to complete a water-resources study through the U.S. Geological Survey, Desert Research Institute, and State of Utah. The study was designed as a regional water-resource assessment, with particular emphasis on summarizing the hydrogeologic framework and hydrologic processes that influence ground-water resources. The study area includes 13 hydrographic areas that cover most of White Pine County; in this report however, results for the northern and central parts of Little Smoky Valley were combined and presented as one hydrographic area. Hydrographic areas are the basic geographic units used by the State of Nevada and Utah and local agencies for water-resource planning and management, and are commonly defined on the basis of surface-water drainage areas. Hydrographic areas were further divided into subbasins that are separated by areas where bedrock is at or near the land surface. Subbasins are the subdivisions used in this study for estimating recharge, discharge, and water budget. Hydrographic areas are the subdivision used for reporting summed and tabulated subbasin estimates.

  9. Uranium potential of precambrian rocks in the Raft River area of northwestern Utah and south-central Idaho. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Black, B.A.

    1980-09-01

    A total of 1214 geochemical samples were collected and analyzed. The sampling media included 334 waters, 616 stream sediments, and 264 rocks. In addition, some stratigraphic sections of Elba and Yost Quartzites and Archean metasedimentary rock were measured and sampled and numerous radiation determinations made of the various target units. Statistical evaluation of the geochemical data permitted recognition of 156 uranium anomalies, 52 in water, 79 in stream sediment, and 25 in rock. Geographically, 68 are located in the Grouse Creek Mountains, 43 in the Raft River Mountains, and 41 in the Albion Range. Interpretation of the various data leads to the conclusion that uranium anomalies relate to sparingly and moderately soluble uraniferous heavy minerals, which occur as sparse but widely distributed magmatic, detrital, and/or metamorphically segregated components in the target lithostratigraphic units. The uraniferous minerals known to occur and believed to account for the geochemical anomalies include allanite, monazite, zircon, and apatite. In some instances samarskite may be important. These heavy minerals contain uranium and geochemically related elements, such as Th, Ce, Y, and Zr, in sufficient quantities to account for both the conspicuous lithologic preference and the generally observed low amplitude of the anomalies. The various data generated in connection with this study, as well as those available in the published literature, collectively support the conclusion that the various Precambrian W and X lithostratigraphic units pre-selected for evaluation probably lack potential to host important Precambrian quartz-pebble conglomerate uranium deposits. Moreover it is also doubted that they possess any potential to host Proterozoic unconformity-type uranium deposits.

  10. PINTURAS RUPESTRES DA REGIÃO ARQUEOLÓGICA DE PIRIPIRI, PIAUÍ, BRASIL (Rock Paintings from the Archaeological Area of Piripiri, Piauí, Brazil

    Directory of Open Access Journals (Sweden)

    Luis Carlos Duarte Cavalcante

    2015-06-01

    Full Text Available O município de Piripiri, no estado do Piauí (Brasil, tem diversos sítios arqueológicos, essencialmente abrigos sob rocha e paredões decorados com pinturas rupestres e/ou gravuras, testemunhos excepcionais de atividade humana antiga. Em particular, os povoados Buriti dos Cavalos, Cadoz Velho e Jardim, localizados na área rural de Piripiri, apresentam algumas inscrições pré-históricas caracterizadas pela beleza exuberante, elevada densidade de registros gráficos e frequente policromia, tornando-se assim áreas de especial interesse para o estudo arqueológico de arte rupestre. Além da policromia, há sobreposições e recorrência dos registros rupestres, pintados em diferentes momentos de evolução gráfica. As pinturas rupestres consistem de grafismos puros e geométricos, carimbos de mãos humanas, motivos antropomórficos e zoomórficos, pintadas em amarelo, preto, cinza (inclusive na cor cinza-esverdeada, rosa, branco, alaranjado e predominantemente em diferentes tonalidades de vermelho. ENGLISH: The municipality of Piripiri, in the state of Piauí (Brazil, has several archaeological sites, essentially rock shelters and walls decorated with rock paintings or engravings, which are exceptional testimonies of ancient human activity. In the rural area of Piripiri, the villages Buriti dos Cavalos, Cadoz Velho, and Jardim, present some prehistoric inscriptions characterized by lush beauty, high density of graphic records, and frequent polychrome. These are areas of special interest to the archaeological study of rock art. In addition to the polychrome, there are overlaps and recurrences of rock records, painted in different moments of graphic evolution. The rock paintings consist of pure and geometric graphisms, human handprints, anthropomorphic and zoomorphic motifs, predominantly made in different tonalities of red, but also painted in yellow, black, gray (including a greenish-gray color, pink, white, and orangish tones.

  11. Collecting Rocks

    Institute of Scientific and Technical Information of China (English)

    孙铮

    2007-01-01

    My hobby is collecting rocks.It is very special,isn’t it?I began to collect rocks about four years ago.I usually go hiking in the mountains,or near the river to look for rocks.When I find a rock,I pick it up and clean it with the brush and water.Then I put it into my bag.Most of the rocks I have collected are quartzite~*.They are really

  12. Closure Report for Corrective Action Unit 329: Area 22 Desert Rock Airstrip Fuel Spill with Errata Sheet, Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    Navarro Nevada Environmental Services

    2010-08-10

    In Appendix 0, Use Restriction (UR) Form, the drawing of the use restricted area shows the incorrect coordinates for the use restricted area, the coordinates on the drawing do not match the approved UR Form. The coordinates have been verified and this Errata Sheet replaces the drawing of the use restricted area with an aerial photo showing the use restricted area and the correct coordinates that match the approved UR Form.

  13. Trace elements and REE fractionation in subsoils developed on sedimentary and volcanic rocks: case study of the Mt. Vulture area, southern Italy

    Science.gov (United States)

    Mongelli, Giovanni; Paternoster, Michele; Rizzo, Giovanna; Sinisi, Rosa

    2014-06-01

    There is an increasing interest in the distribution of rare earth elements (REEs) within soils, primarily as these elements can be used to identify pedogenetic processes and because soils may be future sources for REE extraction, despite much attention should be paid to the protection and preservation of present soils. Here, we evaluate the processes that control the distribution of REEs in subsoil horizons developed over differing lithologies in an area of low anthropogenic contamination, allowing estimates of the importance of source rocks and weathering. Specifically, this study presents new data on the distribution of REEs and other trace elements, including transition and high-field-strength elements, in subsoils developed on both Quaternary silica-undersaturated volcanic rocks and Pliocene siliciclastic sedimentary rocks within the Mt. Vulture area of the southern Apennines in Italy. The subsoils in the Mt. Vulture area formed during moderate weathering (as classified using the chemical index of alteration) and contain an assemblage of secondary minerals that is dominated by trioctahedral illite with minor vermiculite. The REEs, high-field-strength elements, and transition metals have higher abundances in subsoils that developed from volcanic rocks, and pedogenesis caused the Mt. Vulture subsoils to have REE concentrations that are an order of magnitude higher than typical values for the upper continental crust. This result indicates that the distribution of REEs in soils is a valuable tool for mineral exploration. A statistical analysis of inter-elemental relationships indicates that REEs are concentrated in clay-rich fractions that also contain significant amounts of low-solubility elements such as Zr and Th, regardless of the parent rock. This suggests that low-solubility refractory minerals, such as zircon, play a significant role in controlling the distribution of REEs in soils. The values of (La/Yb)N and (Gd/Yb)N fractionation indices are dependent on

  14. Geomorphologic mapping in the Ny Ålesund area (Svalbard Island, Norway) for the analysis of geomorphologic effects on rock slopes induced by glacier retreat in climate sensitive High Arctic regions

    Science.gov (United States)

    Miccadei, Enrico; Piacentini, Tommaso; Casacchia, Ruggero; Sparapani, Roberto

    2014-05-01

    The geomorphological effects of glacial retreat, rapidly changing Arctic environments and consequent local temporary permafrost melting are several types of glacial and periglacial landforms (pingos, solifluction, drumlins, etc.) but also debris and rock falls, alluvial fan and glacial outwash development and scarp/slopes retreat and evolution. In this work we have realized a geomorphologic map of rockfalls, landslides, alluvial fans and the slopes and scarps of steep mountainsides in the Ny Ålesund area (Svalbard Island, Norway) focused on the analysis of rock falls as geomorphological effects of glacier retreat, permafrost degradation and higher temperatures on slope processes. The investigation is based on geological and geomorphological field survey, and remote sensing and aerial photo interpretation, The Ny Ålesund area landscape is characterized by rugged non-vegetated mountains only partially covered by glaciers, with steep flanks and rock scarps; the scarps are formed by different types of rocks (intrusive and effusive igneous rocks, marine sedimentary rocks); this landscape is highly affected by debris and rock falls (from scarps and slopes) forming wide talus slopes and by alluvial fan and fluvial outwash (from glaciers), which make the surface sedimentary cover of the island together with rock glaciers and moraine deposits and locally fluvial deposits. The work is focused on the comprehension of the role of different factors in inducing rock falls, alluvial fans, slope/scarps evolution in high geomorphological sensitivity environments (i.e. glacial, periglacial or mountain) including: orography, lithology, rock fracturation, morphostructural setting, meteorological context. The conclusions focus on the possible geomorphological hazards affecting the Ny Ålesund area.

  15. Diagenesis of the Sedimentary Rocks Enclosing Coaly Layers in Gavatha Area,Lesvos Island,Based on Silica Polymorph‘s Transformations

    Institute of Scientific and Technical Information of China (English)

    A.KELEPERTSIS

    1996-01-01

    A Tertiary non-marine stratigraphic sequence composed of carbonates(limestone),siliceous carbonates,coaly layers overlain by pyroclastic rocks and lavas,outcrops in the Gavatha area of northwestern Lesvos Island.Pure earbonates eonsist almost completely of calcite,the siliceous carbonate sediments of quartz,opal-CT and calcite,the shales of quartz,opal CT, K-feldspar,smecite-illite and ealcite,and the coaly layers of organic matter,quartz,opal-CT,feldspars and pyrite,Geochemical data indicate that smectite-illite,feldspars and associated elements(La,Zr,Y,Ba,Ce)are the products of alteration of volcanic rocks in a subtropical area A combination of sources in suggested for the formation of silica polymorphs:(a) biogenic or non-biogenic silica(opal-A) that was originally present in the form of diatiom frustules of in the form of inorganically prccipitated silica;(b)transformation o opall-A to opal-CT and quartz opal-C from alteration of volcanic glass of intercalated tuffites and overlying volcanics;and(c)opal-CT deposited primarily from hydrothermal solutions.

  16. Art on Rock

    Institute of Scientific and Technical Information of China (English)

    HU YUE

    2010-01-01

    @@ With sprawling deserts and serene lakes, the natural wonders of Ningxia Hui Autonomous Region have never failed to take the breath away from visitors. The area has another major attraction, though: the Helan Mountain rock engravings.

  17. Geochemistry, petrography, and zircon U-Pb geochronology of Paleozoic metaigneous rocks in the Mount Veta area of east-central Alaska: implications for the evolution of the westernmost part of the Yukon-Tanana terrane

    Science.gov (United States)

    Dusel-Bacon, Cynthia; Day, Warren C.; Aleinikoff, John N.

    2013-01-01

    We report the results of new mapping, whole-rock major, minor, and trace-element geochemistry, and petrography for metaigneous rocks from the Mount Veta area in the westernmost part of the allochthonous Yukon–Tanana terrane (YTT) in east-central Alaska. These rocks include tonalitic mylonite gneiss and mafic metaigneous rocks from the Chicken metamorphic complex and the Nasina and Fortymile River assemblages. Whole-rock trace-element data from the tonalitic gneiss, whose igneous protolith was dated by SHRIMP U–Pb zircon geochronology at 332.6 ± 5.6 Ma, indicate derivation from tholeiitic arc basalt. Whole-rock analyses of the mafic rocks suggest that greenschist-facies rocks from the Chicken metamorphic complex, a mafic metavolcanic rock from the Nasina assemblage, and an amphibolite from the Fortymile River assemblage formed as island-arc tholeiite in a back-arc setting; another Nasina assemblage greenschist has MORB geochemical characteristics, and another mafic metaigneous rock from the Fortymile River assemblage has geochemical characteristics of calc-alkaline basalt. Our geochemical results imply derivation in an arc and back-arc spreading region within the allochthonous YTT crustal fragment, as previously proposed for correlative units in other parts of the terrane. We also describe the petrography and geochemistry of a newly discovered tectonic lens of Alpine-type metaharzburgite. The metaharzburgite is interpreted to be a sliver of lithospheric mantle from beneath the Seventymile ocean basin or from sub-continental mantle lithosphere of the allochthonous YTT or the western margin of Laurentia that was tectonically emplaced within crustal rocks during closure of the Seventymile ocean basin and subsequently displaced and fragmented by faults.

  18. Rock Stars

    Institute of Scientific and Technical Information of China (English)

    张国平

    2000-01-01

    Around the world young people are spending unbelievable sums of money to listen to rock music. Forbes Magazine reports that at least fifty rock stars have incomes between two million and six million dollars per year.

  19. KREEP Rocks

    Institute of Scientific and Technical Information of China (English)

    邹永廖; 徐琳; 欧阳自远

    2004-01-01

    KREEP rocks with high contents of K, REE and P were first recognized in Apollo-12 samples, and it was confirmed later that there were KREEP rock fragments in all of the Apollo samples, particularly in Apollo-12 and-14 samples. The KREEP rocks distributed on the lunar surface are the very important objects of study on the evolution of the moon, as well as to evaluate the utilization prospect of REE in KREEP rocks. Based on previous studies and lunar exploration data, the authors analyzed the chemical and mineral characteristics of KREEP rocks, the abundance of Th on the lunar surface materials, the correlation between Th and REE of KREEP rocks in abundance, studied the distribution regions of KREEP rocks on the lunar surface, and further evaluated the utilization prospect of REE in KREEP rocks.

  20. Origin and geochemistry of Pan-African granitoid rocks in the Gabal Um Shomer area, Southwestern Sinai, Egypt

    Institute of Scientific and Technical Information of China (English)

    E1-Tokhi M.M.; Musallum A.; Amin B.M.

    2009-01-01

    Geological, petrological and geochemical studies indicated that there are two distinct types of granitoid rocks: older quartz diorites to granodiorite assemblage and younger granitoids, the latter occurring in two phases. The older granitoids have a meta-aluminous chemistry and a calc-alkaline character, with high MgO, Fe2O3, TiO2, CaO, P2O5, Sr and low SiO2, K2O, and Rb. Their major and trace elements data, together with low 87Sr/ 86Sr ratios (0.7029±0.0008) are indicative of I-type affinities. The second- and third-phase granitoids range from calc-alkaline to alkaline, respectively. The second-phase granitoids have a peraluminous chemistry and high Sr, Ba, CaO, MgO, Al2O3 and Ti2O and low SiO2, K2O, Nb, Y and Rb relative to the third-phase granitoids. The corundum normative nature and field observations suggested that it was formed by partial melting of the lower crust. The third-phase granitoids are alkaline in nature and characterized by higher SiO2, Rb, Y, Nb and lower MgO, Sr and Ba values than the younger granitoids (phase II). They are A-type granitoids which were generated from below or within the existing continental crust.

  1. Paleomagnetic secular variation study of Ar-Ar dated lavas flows from Tacambaro area (Central Mexico): Possible evidence of Intra-Jaramillo geomagnetic excursion in volcanic rocks

    Science.gov (United States)

    Peña, Rafael Maciel; Goguitchaichvili, Avto; Guilbaud, Marie-Noëlle; Martínez, Vicente Carlos Ruiz; Rathert, Manuel Calvo; Siebe, Claus; Reyes, Bertha Aguilar; Morales, Juan

    2014-04-01

    More than 350 oriented paleomagnetic cores were obtained for rock-magnetic and paleomagnetic analysis from radiometrically dated (40Ar-39Ar) magmatic rocks occurring in the southern segment (Jorullo and Tacámbaro areas) of the Michoacán-Guanajuato Volcanic Field in the Trans-Mexican Volcanic Belt. Most of the lavas (37) stem from monogenetic volcanoes dated at less than 4 Ma. Two additional sites were sampled from the plutonic basement dated at 33-30 Ma. Primary remanences carried by low-Ti titanomagnetites allowed to determining 34 reliable site-mean directions of mostly normal (27) but also reversed (7) polarities. The mean directions of these two populations are antipodal, and suggest neither major vertical-axis rotations with respect to the North America craton nor tilting in the region for the last 4 Ma (rotation and flattening of the inclination parameters being less than -5.9 ± 3.8 and 0.1 ± 3.9, respectively). The corresponding paleomagnetic pole obtained for Pliocene-Pleistocene times is PLAT = 83.4°, PLON = 2.4° (N = 32, A95 = 2.7°). Virtual geomagnetic poles also contribute to the time averaged field global database and to the paleosecular variation (PSV) investigations at low latitudes from lavas for the last 5 Ma, showing a geomagnetic dispersion value that is in agreement with available PSV models. When comparing the magnetic polarities and corresponding radiometric ages of the studied sites with the Cenozoic geomagnetic polarity time scale (GPTS), a good correlation is observable. This finding underscores the suitability of data obtained on lavas in Central Mexico for contributing to the GPTS. Furthermore, the detection of short-lived geomagnetic features seems possible, since the possible evidence of Intra-Jaramillo geomagnetic excursion could be documented for the first time in these volcanic rocks.

  2. Application of Clinopyroxene Chemistry to Interpret the Physical Conditions of Ascending Magma, a Case Study of Eocene Volcanic Rocks in the Ghohrud Area (North of Isfahan

    Directory of Open Access Journals (Sweden)

    Mohammad Sayari

    2016-07-01

    Full Text Available Introduction Volcanic rocks with a porphyritic texture have experienced two crystallization stages. The first is slow, resulting in phenocrysts, and the second, which took place at, or near the surface, or during intrusion into a cooler body of rock, result in a groundmass of glass, or fine crystals. The pressure and temperature history of a magma during crystallization is recorded in the chemical composition of the phenocrysts during both stages. These phenocrysts provide valuable data about the physicochemical conditions of the parent magma during the process of crystallization. The composition of clinopyroxene (cpx reflects not only the chemical condition and therefore the magmatic series, but also the physical conditions, i.e., temperature and pressure of a magma at the time when clinopyroxene crystallized. The Ghohrud area lies in the middle part of the Urumieh-Dokhtar Magmatic Arc , which is part of a much larger magmatic province extending in a vast region of convergence between Arabia and Eurasia north of the Zagros-Bitlis suture zone (Dilek et al., 2010. In the Ghohrud area, north of Isfahan, exposed Eocene volcanic rocks belong to the first pulse of Cenozoic volcanism of Iran (Sayari, 2015, ranging in composition from andesitic basalt to basalt. The basaltic rocks of the Ghohrud area are composed mainly of plagioclase phenocrysts surrounded by smaller crystals of clinopyroxene in a groundmass of microlites, glass and opaques. In this study, the clinopyroxene and plagioclase of these rocks were analyzed in order to estimate the physicochemical conditions of the parent magmas. Results Clinopyroxene and plagioclase phenocrysts of nineteen samples were analyzed with the electron microprobe. The chemical compositions of the clinopyroxenes were used to estimate both the chemical evolution and temperature and pressure conditions of the magmas during crystallization, using SCG, a specialized software for clinopyroxene thermobarometry (Sayari

  3. Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Grecian Rocks, 2007 - 2010 (NODC Accession 0093026)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

  4. Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Grecian Rocks, 2005 - 2007 (NODC Accession 0039973)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

  5. Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Grecian Rocks, 1990 - 2005 (NODC Accession 0011143)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

  6. Rock Art

    Science.gov (United States)

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  7. Rock Art

    Science.gov (United States)

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  8. Rock Finding

    Science.gov (United States)

    Rommel-Esham, Katie; Constable, Susan D.

    2006-01-01

    In this article, the authors discuss a literature-based activity that helps students discover the importance of making detailed observations. In an inspiring children's classic book, "Everybody Needs a Rock" by Byrd Baylor (1974), the author invites readers to go "rock finding," laying out 10 rules for finding a "perfect" rock. In this way, the…

  9. Hydrographic Areas Within the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada and Adjacent Areas in Nevada and Utah

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of sub delineations of the hydrographic area (HA) boundaries and polygons drawn at 1:1,000,000 scale for the Great Basin supplemented by...

  10. Geochemical characteristics of amphibole in the gabbroic rocks of the medial area of the Godzilla Megamullion, Parece Vela Basin, Philippine Sea

    Science.gov (United States)

    Harigane, Y.; Morishita, T.; Snow, J. E.; Tamura, A.; Michibayashi, K.; Ohara, Y.; Arai, S.

    2011-12-01

    The oceanic core complexes (OCCs) are found on most slow spreading ridges proposed by Escartin et al. (2008), which has been suggested that OCC along a spreading axis represent the megamullion in morphological structure and the oceanic detachment fault in formation process by analogy of continental metamorphic core complex. The Godzilla Megamullion (GM), the largest OCC in the world, is located at the extinct Parece Vela Basin spreading ridge in the Philippine Sea (Ohara et al., 2001). Fault rocks are common on the surface of the GM, indicating the presence of a detachment fault exposed on the seafloor (Harigane et al., 2011). Harigane et al. (2008) reported that the hydrothermal metamorphism occurred retrogressively at the gabbroic rocks during the deformation related to the detachment fault. However, the origins of fluids and the fluid-rock interaction during deformation for the detachment fault are still unsolved. In this study, we present trace element geochemical analyses of amphibole and clinopyroxene of the gabbroic rocks sampled from the medial area of the GM using LA-ICP-MS at Kanazawa University and University of Houston. Most of the gabbroic rocks show a porphyroclastic texture that consist of plagioclase/clinopyroxene porphyroclasts and a fine-grained plagioclase/clinopyroxene/amphibole matrix. The amphibole compositions consist of pargasite and magnesio-hornblende (i.e. brown hornblende) with minor actinolite (i.e. green hornblende). These brown hornblendes have two distinct types in microstructure: bleb type and rim type. The bleb type occurs in the cores of clinopyroxene porphyroclasts and has no evidence of deformation. The rim type occurs as fine grains at the rim of clinopyroxene porphyroclasts. All green hornblende grains show no evidence of deformation and occur at the rim of brown hornblende and clinopyroxene grains. All chondrite-normalized REE patterns of clinopyroxene in the gabbroic rocks are characterized by flat heavy-REE and light

  11. Ground stress and its impact on the stability of the surrounding rock in the Lüliang mining area

    Institute of Scientific and Technical Information of China (English)

    Wang Lianguo; Lu Yinlong

    2011-01-01

    Ground stress is the fundamental cause of deformation and failure during underground structural engineering.Field stress measurements in the main coal bed in the Lüliang mining area were made by the bore hole,stress relief method.From these data the ground stress distribution of the mining area was obtained.The relationship between the horizontal principal stress and the deformation and failure of a roadway is discussed with an engineering example.The results indicate that horizontal stress dominates in the shallow crust in the Lüliang mining area.Roadways at different angles to the maximum principal stress have different levels of stress concentration.This leads to a significant difference in stability of the corresponding roadways.These research results provide an important criterion for determining roadway position and direction,stope layout,and roadway support design.

  12. An analysis of fracture trace patterns in areas of flat-lying sedimentary rocks for the detection of buried geologic structure. [Kansas and Texas

    Science.gov (United States)

    Podwysocki, M. H.

    1974-01-01

    Two study areas in a cratonic platform underlain by flat-lying sedimentary rocks were analyzed to determine if a quantitative relationship exists between fracture trace patterns and their frequency distributions and subsurface structural closures which might contain petroleum. Fracture trace lengths and frequency (number of fracture traces per unit area) were analyzed by trend surface analysis and length frequency distributions also were compared to a standard Gaussian distribution. Composite rose diagrams of fracture traces were analyzed using a multivariate analysis method which grouped or clustered the rose diagrams and their respective areas on the basis of the behavior of the rays of the rose diagram. Analysis indicates that the lengths of fracture traces are log-normally distributed according to the mapping technique used. Fracture trace frequency appeared higher on the flanks of active structures and lower around passive reef structures. Fracture trace log-mean lengths were shorter over several types of structures, perhaps due to increased fracturing and subsequent erosion. Analysis of rose diagrams using a multivariate technique indicated lithology as the primary control for the lower grouping levels. Groupings at higher levels indicated that areas overlying active structures may be isolated from their neighbors by this technique while passive structures showed no differences which could be isolated.

  13. Sub-crop geologic map of pre-Tertiary rocks in the Yucca Flat and northern Frenchman Flat areas, Nevada Test Site, southern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Cole, J.C.; Harris, A.G.; Wahl, R.R.

    1997-10-02

    for ground water flow through pre-Tertiary rocks beneath the Yucca Flat and northern Frenchman Flat areas, and has consequences for ground water modeling and model validation. Our data indicate that the Mississippian Chainman Shale is not laterally extensive confining unit in the western part of the basin because it is folded back onto itself by the convergent structures of the Belted Range and CP thrust systems. Early and Middle Paleozoic limestone and dolomite are present beneath most of both basins and, regardless of structural complications, are interpreted to form a laterally continuous and extensive carbonate aquifer. Structural culmination that marks the French Peak accommodation zone along the topographic divide between the two basins provides a lateral pathway through highly fractured rock between the volcanic aquifers of Yucca Flat and the regional carbonate aquifer. This pathway may accelerate the migration of ground-water contaminants introduced by underground nuclear testing toward discharge areas beyond the Nevada Test Site boundaries. Predictive three-dimensional models of hydrostratigraphic units and ground-water flow in the pre-Tertiary rocks of subsurface Yucca Flat are likely to be unrealistic due to the extreme structural complexities. The interpretation of hydrologic and geochemical data obtained from monitoring wells will be difficult to extrapolate through the flow system until more is known about the continuity of hydrostratigraphic units. 1 plate

  14. Evidence for CO2-rich fluids in rocks from the type charnockite area near Pallavaram, Tamil Nadu

    Science.gov (United States)

    Hansen, E.; Hunt, W.; Jacob, S. C.; Morden, K.; Reddi, R.; Tacy, P.

    1988-01-01

    Fluid inclusion and mineral chemistry data was presented for samples from the type charnockite area near Pallavaram (Tamil Nadu, India). The results indicate the presence of a dense CO2 fluid phase, but the data cannot distinguish between influx of this fluid from elsewhere or localized migration of CO2-rich fluids associated with dehydration melting.

  15. Raw data from orientation studies in crystalline rock areas of the southeastern United States. [Maps, tables of field data and analytical data for sections of North and South Carolina and Georgia, previously reported sites of uranium mineralization

    Energy Technology Data Exchange (ETDEWEB)

    Price, V.

    1976-03-01

    Raw data are presented on orientation studies conducted in crystalline rock areas of the Southeast which were chosen because of published references to uranium mineralization. Preliminary data for four orientation study areas are included. These areas are Lamar County, Georgia; Oconee County, South Carolina; Brush Creek, North Carolina; and North Harper, North Carolina. Sample locality maps, tables of field data, and tables of analytical data are included for each study area. (JGB)

  16. Annual Post-Closure Inspection and Monitoring Report for Corrective Action Unit 329: Area 22 Desert Rock Airstrip Fuel Spill, Nevada Test Site, Nevada, Rev. No.: 0

    Energy Technology Data Exchange (ETDEWEB)

    Alfred Wickline

    2006-09-01

    This report presents the data collected during field activities and quarterly soil-gas sampling activities conducted from May 9, 2005, through May 20, 2006, at Corrective Action Unit (CAU) 329, Area 22 Desert Rock Airstrip (DRA) Fuel Spill; Corrective Action Site (CAS) 22-44-01, Fuel Spill. The CAU is located at the DRA, which is located approximately two miles southwest of Mercury, Nevada, as shown in Figure 1-1. Field activities were conducted in accordance with the revised sampling approach outlined in the Addendum to the Closure Report (CR) for CAU 329 (NNSA/NSO, 2005) to support data collection requirements. The previous annual monitoring program for CAU 329 was initiated in August 2000 using soil-gas samples collected from three specific intervals at the DRA-0 and DRA-3 monitoring wells. Results of four sampling events from 2000 through 2003 indicated there is uncertainty in the approach to establish a rate of natural attenuation as specified in ''Streamlined Approach for Environmental Restoration (SAFER) Work Plan for Corrective Action Unit 329: Area 22 Desert Rock Airstrip Fuel Spill, Nevada Test Site, Nevada'' (DOE/NV, 1999). As a result, the Addendum to the CR (NNSA/NSO, 2005) was completed to address this uncertainty by modifying the previous approach. A risk evaluation was added to the scope of the project to determine if the residual concentration of the hazardous constituents of JP4 pose an unacceptable risk to human health or the environment and if a corrective action was required at the site, because the current quarterly monitoring program is not expected to yield a rate constant that could be used effectively to determine a biodegradation rate for total petroleum hydrocarbons (TPH) in less than the initial five years outlined in the CR. Additionally, remediation to the Tier 1 action level for TPH is not practical or technically feasible due to the depth of contamination.

  17. Petrogenesis of gold-mineralized magmatic rocks of the Taerbieke area, northwestern Tianshan (western China): Constraints from geochronology, geochemistry and Sr-Nd-Pb-Hf isotopic compositions

    Science.gov (United States)

    Tang, Gong-Jian; Wang, Qiang; Wyman, Derek A.; Sun, Min; Zhao, Zhen-Hua; Jiang, Zi-Qi

    2013-09-01

    the formation of the Early Carboniferous andesites and granitic porphyries in the Taerbieke area were related to the Paleo-Junggar Oceanic plate southward subduction under the Yili-Central Tianshan plate. The close association of the Early Carboniferous magmatic rocks and Au mineralization in the Taerbieke area suggests that the arc magmatic rocks in the Tulasu basin may have a high potential for Au mineralization.

  18. Geochemistry and U-Pb zircon geochronology of the pegmatites in Ede area, southwestern Nigeria: A newly discovered oldest Pan African rock in southwestern Nigeria

    Science.gov (United States)

    Adetunji, A.; Olarewaju, V. O.; Ocan, O. O.; Ganev, V. Y.; Macheva, L.

    2016-03-01

    Field and petrographic studies, whole rock geochemistry and in-situ LA-ICP-MS geochemical and isotopic U-Pb measurements on zircons have been performed on granitic pegmatites of Ede area, southwestern Nigeria with a view to characterize them, determining their mineralization potentials, petrogenetic attributes and emplacement age. The pegmatites are hosted by migmatite gneiss complex, biotite-muscovite schist and associated quartzite. The textural and mineralogical characteristics of these pegmatites indicate the occurrence of two main varieties, namely, muscovite pegmatite and garnet pegmatite. Of less importance are inclusions and pods of graphic granite, quartz-microcline aplitic and pegmatitic bodies. At the present level of erosion, the parent igneous rocks of the pegmatites are not exposed. The two dominant pegmatite varieties show slightly different chemical peculiarities but similar peraluminous character. The average K/Rb ratios of 165 and 163, respectively, for muscovite and garnet pegmatites combined with other trace element compositions are indicative of affinity to muscovite class of pegmatite which are generally not promising for rare elements mineralization. However, the unusually high concentration of bismuth in the zircons indicates Bi mineralization in the area which can either be in the pegmatites or host rocks. The Nb/Ta ratios for both muscovite and garnet pegmatites range from 0.7 to 15.2 and 1.0 to 14.8, respectively. These Nb/Ta ratios and Eu anomalies are statistically similar for both pegmatites. These probably indicate the pegmatites crystallized from a common source but separated into crystallization paths that produced different pegmatite varieties through liquid-liquid immiscibity mechanism. In-situ measurements of REE, P, Y, Nb, Hf, Ta, Bi, Th and U of individual zircon grains show the existence of two chemically and texturally different domains which are indicative of alteration that may be due to interface-coupled dissolution

  19. Faunal associations, paleoecology and paleoenvironment of marine Jurassic rocks in the Mae Sot, Phop Phra, and Umphang areas, western Thailand

    Institute of Scientific and Technical Information of China (English)

    MEESOOK; Assanee; YAMEE; Chotima; SAENGSRICHAN; Wirote

    2009-01-01

    We here report a paleoecological analysis and depositional history of the marine Jurassic (Toarcian–early Bajocian) strata cropping out in the western part of Thailand, based on bivalve assemblages with additional data from ammonites, brachiopods, and microfossils. Generally, the benthic bivalve facies in most outcrops is rich in infaunal, semi-infaunal and epifaunal suspension-feeders. Of these, infaunal forms dominate. The diversity of this benthic assemblage was influenced by energy level, substrate, sedimentation rate, and salinity. Low to intermediate energy levels and rather soft fine-grained siliciclastic substrate are proposed as factors governing faunal distribution and explaining the greater abundance and diversity of infaunal than epifaunal suspension-feeders. There were paleoenvironmental changes both in space and time, i.e., from south to north (Umphang to Mae Sot) and from Early Bajocian to Toarcian. In the Toarcian, most outcrops in Umphang are dominated by benthic bivalve facies (infaunal, semi-infaunal, and epifaunal associations). This implies warm, shallow water (inner neritic, 50―100 m) and oxygenated conditions except for the Mae Sot area where a deeper setting (outer neritic to possibly upper continental slope, 50―200 m) with restricted basinal anoxic conditions is favored as indicated by the presence of Bositra. After higher energy conditions in the Toarcian, lower energy conditions with low sediment supplies prevail in the Alenian, and the Mae Sot area was still a restricted basin. As a result of higher sea levels, the oxygen content in the basin is increased, resulting in the presence of the ammonites. By the end of the Alenian-early Bajocian, an ammonite-bivalve association (mixed facies A) and the presence of corals and microfauna (mixed facies B) are dominant but pass upwards to near-shore higher energy conditions in most areas except for restricted basin in Mae Sot. By the middle Bajocian the environment in all areas had changed

  20. 'Escher' Rock

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks [figure removed for brevity, see original site] Figure 1 This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water. Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend. These data were taken by the rover's alpha particle X-ray spectrometer.

  1. 'Escher' Rock

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks [figure removed for brevity, see original site] Figure 1 This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water. Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend. These data were taken by the rover's alpha particle X-ray spectrometer.

  2. 'Earhart' Rock

    Science.gov (United States)

    2004-01-01

    This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock informally named 'Earhart' on the lower slopes of 'Endurance Crater.' The rock was named after the pilot Amelia Earhart. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe fractures in Earhart could have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Rover team members do not have plans to investigate Earhart in detail because it is located across potentially hazardous sandy terrain. This image was taken on sol 219 (Sept. 4) by the rover's panoramic camera, using its 750-, 530- and 430-nanometer filters.

  3. Revised conceptual hydrogeologic model of a crystalline rock environment, Whiteshell Research Area, Southeastern Manitoba, Canada; Modele hydrogeologique conceptual revise d`un milieu de roche cristalline, aire de recherche de whiteshell, sud-est du manitoba au canada

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, D.R.; Brown, A.; Davison, C.C.; Gascoyne, M.; McGregor, R.G.

    1996-04-01

    A revised conceptual hydrogeologic model of regional groundwater flow in the crystalline rocks of the Whiteshell Research Area (WRA) has been developed by a team of AECL geoscientists. The boundaries of the revised conceptual model were selected to coincide with the natural hydraulic boundaries assumed for the regional groundwater flow systems in the WRA. The rocks of the modeled region were divided on the basis of fracture characteristics into three categories: fractured zones (FZs); moderately fractured rock (MFR); and sparsely fractured rock (SFR). The hydraulic properties of the revised conceptual model were modified during an interative process of mathematical model calibration and conceptual model revision. This process included sensitivity analysis and matching of equivalent fresh water hydraulic head and groundwater flux values calculated by the mathematical model and comparison with the field measurements.

  4. Rock Art

    OpenAIRE

    Huyge, Dirk

    2009-01-01

    Rock art, basically being non-utilitarian, non-textual anthropic markings on natural rock surfaces, was an extremely widespread graphical practice in ancient Egypt. While the apogee of the tradition was definitely the Predynastic Period (mainly fourth millennium BCE), examples date from the late Palaeolithic (c. 15,000 BCE) until the Islamic era. Geographically speaking, “Egyptian” rock art is known from many hundreds of sites along the margins of the Upper Egyptian and Nubian Nile Valley and...

  5. Rock blocks

    OpenAIRE

    Turner, W.

    2007-01-01

    Consider representation theory associated to symmetric groups, or to Hecke algebras in type A, or to q-Schur algebras, or to finite general linear groups in non-describing characteristic. Rock blocks are certain combinatorially defined blocks appearing in such a representation theory, first observed by R. Rouquier. Rock blocks are much more symmetric than general blocks, and every block is derived equivalent to a Rock block. Motivated by a theorem of J. Chuang and R. Kessar in the case of sym...

  6. Home area geology and Alabama earth science teachers: A resource to improve the understanding and use of the state's rocks to supplement textbook concepts in earth history

    Science.gov (United States)

    Lacefield, James Anderson

    Recent studies have suggested that teachers of earth science in Alabama secondary schools are undertrained in the content areas of the subject. A survey of academic training and certification of active earth science teachers (Hall, 1985) was replicated as part of a study of the current inservice needs of Alabama earth science teachers (Logue & Lacefield, 1995). Only one-third of responding teachers were found to be properly certified to teach the subject; most had been trained for teaching life science. Approximately one-half had never had a course in geology, astronomy, or meteorology--the three primary components of the typical earth science course. Of 32 earth science topics suggested for possible additional inservice workshops, teachers responding to the Logue and Lacefield survey selected Alabama and Southeastern geology as the topic of greatest interest and need. As an alternative to conventional inservice training, an illustrated book on Alabama geologic history was developed for publication. Its purpose was to supply an ongoing, usable geologic reference for Alabama earth science teachers and their students and to promote greater understanding of Alabama geology by the public in general. Entitled Lost Worlds in Alabama Rocks: The Half-Billion Year Record of Change in the State's Life and Landscape, the 82-page book (included as appendix) explains how geologic history is reconstructed using evidence from rocks, surveys the major sets of sedimentary rocks found within the state, details what each means in terms of ancient environment, and describes how Alabama's present landscape can be interpreted to reflect past geologic changes. The resource includes nearly 200 color photographs and graphics and 12 pages of fossil identification guides illustrating the most common fossil organisms found within the state. A selected group of professional geologists and earth science educators evaluated the book for scientific accuracy, format, presentation of content, and

  7. Trace element and isotopic composition of apatite in carbonatites from the Blue River area (British Columbia, Canada) and mineralogy of associated silicate rocks

    Science.gov (United States)

    Mitchell, Roger; Chudy, Thomas; McFarlane, Christopher R. M.; Wu, Fu-Yuan

    2017-08-01

    Apatites from the Verity, Fir, Gum, Howard Creek and Felix carbonatites of the Blue River (British Columbia, Canada) area have been investigated with respect to their paragenesis, cathodoluminescence, trace element and Sr-Nd isotopic composition. Although all of the Blue River carbonatites were emplaced as sills prior to amphibolite grade metamorphism and have undergone deformation, in many instances magmatic textures and mineralogy are retained. Attempts to constrain the U-Pb age of the carbonatites by SIMS, TIMS and LA-ICP-MS studies of zircon and titanite were inconclusive as all samples investigated have experienced significant Pb loss during metamorphism. The carbonatites are associated with undersaturated calcite-titanite amphibole nepheline syenite only at Howard Creek although most contain clasts of disaggregated phoscorite-like rocks. Apatite from each intrusion is characterized by distinct, but wide ranges, in trace element composition. The Sr and Nd isotopic compositions define an array on a 87Sr/86Sr vs²Nd diagram at 350 Ma indicating derivation from depleted sub-lithospheric mantle. This array could reflect mixing of Sr and Nd derived from HIMU and EM1 mantle sources, and implies that depleted mantle underlies the Canadian Cordillera. Although individual occurrences of carbonatites in the Blue River region are mineralogically and geochemically similar they are not identical and thus cannot be considered as rocks formed from a single batch of parental magma at the same stage of magmatic evolution. However, a common origin is highly probable. The variations in the trace element content and isotopic composition of apatite from each occurrence suggest that each carbonatite represents a combination of derivation of the parental magma(s) from mineralogically and isotopically heterogeneous depleted mantle sources coupled with different stages of limited differentiation and mixing of these magmas. We do not consider these carbonatites as primary direct

  8. Low- and intermediate level radioactive waste from Risoe, Denmark. Location studies for potential disposal areas. Report no. 2. Characterization of low permeable and fractured sediments and rocks in Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Gravesen, P.; Nilsson, B.; Schack Pedersen, S.A.; Binderup, M.; Laier, T.

    2011-07-01

    The low and intermediate level radioactive waste from Risoe (the nuclear reactor buildings plus different types of material from the research periods) and radioactive waste from hospitals and research institutes have to be stored in a final disposal in Denmark for at least 300 years. In Denmark, many different kinds of fine-grained sediments and crystalline rocks occur from the ground surface down to 300 meters depth. Therefore, the possible geological situations include sediments and rocks of different composition and age. These situations are geographical distributed over large areas of Denmark. These sediments and rocks are shortly described based on existing information and include five different major types of sediments and rocks: 1: Crystalline granite and gneiss of Bornholm (because these rock types are host for waste disposals in many other countries). 2: Sandstone and shale from Bornholm (as these sediments are rela- tively homogeneous although they have fracture permeability). 3: Chalk and limestone (because these sediments may act as low permeable seals, but in most areas they act as groundwater reservoirs). 4: Fine-grained Tertiary clay deposits (as these sediments have a low permeability, are widely distributed and can reach large thicknesses). 5: Quaternary glacial, interglacial and Holocene clay deposits. These sediments are distributed all over Denmark. Following the descriptions of the geologic deposits, the areas below (including several possible locations for waste disposal sites) are selected for further investigation. The Precambrian basement rocks of Bornholm could be host rocks for the disposal. The rock types for further evaluation will be: Hammer Granite, Vang Granite, Roenne Granite, Bornholm gneiss, Paradisbakke Migmatite and Alminding Granite. In the Roskilde Fjord area around Risoe, a combination of Paleocene clays, meltwater clay and clayey till could be interesting. The area is partly included in the OSD area in North Sjaelland but

  9. Interstratified arkosic and volcanic rocks of the Miocene Spanish Canyon Formation, Alvord Mountain area, California: descriptions and interpretations

    Science.gov (United States)

    Buesch, David C.

    2014-01-01

    The Spanish Canyon Foundation in the Alvord Mountain area, California, varies from about 50 to 120 m thick and records the interstratification of arkosic sandstone and conglomerate with tuffaceous deposits and lava flows. In the lower third of the formation, arkosic sandstone and conglomerate are interstratified with tuffaceous deposits. Some tuffs might have been deposited as primary, nonwelded to partially welded ignimbrites or fallout tephra. Many of the tuffaceous deposits represent redeposited material that formed tuffaceous sandstone, and many of these deposits contain arkosic grains that represent mixing of different source matieral. Arkosic sandstone, and especially conglomerate (some with maximum clast lengths up to 1 m), represent intermittent incursions of coarser plutoniclastic fan deposits into other finer grained and mostly volcaniclastic basin deposits. After deposition of the 18.78 Ma Peach Spring Tuff, the amount of tuffaceous material decreased. The upper two-thirds of the formation has arkosic sandstone and conglomerate interstratified with two olivine basalt lave flows. locally, conglomerate clasts in this part of the section have maximum lengths up to 1 m. Many tuffaceous and arkosic sandstone beds of the Spanish Canyon Formation have tabular to broad (low-relief) lenticular geometry, and locally, some arkosic conglomerate fills channels as much as 1.5 m deep. These bedforms are consistent with deposition in medial to distal alluvial-fan or fluvial environments; some finer-grained deposits might have formed in lacustrine environments.

  10. Depth determination of the subsurface uranium deposits using CR-39 cylindrical technique in Gneissoic granitic rocks, Abu Rushied area, Southeastern Desert, Egypt

    Directory of Open Access Journals (Sweden)

    Sayed F. Hassan

    2015-10-01

    Full Text Available Using solid state nuclear track detectors and employing CR-39 cylindrical technique, the depth of the subsurface uranium deposits were determined. This techniques depends mainly on the nuclear track detector situated in zigzag form inside a polyethylene cylinder of 65 cm length and 7 cm diameter. This technique was applied on a borehole in a granite mass Abu Rushied area, southeast area desert. The obtained results revealed that, the depth of U -ore deposited reached about 89 m with thickness nearly 24 m. The obtained data for radon concentrations were also used for the determination of the exhalation rates, the measured values for exhalation rate (mBqm−2h−1 varies between 6.14E-03 at h = 50 cm and 4.53E-02 at h = 10 cm, The obtained values are comparable with that recorded for the granite type of rock.

  11. Rock Art in Kurdistan Iran

    Directory of Open Access Journals (Sweden)

    Jamal Lahafian

    2013-12-01

    Full Text Available Kurdistan, with great potential and prehistoric resources, has numerous petroglyphs in different areas of the province. During the last 14 years of extensive field study, more than 30 sites of rock art have been identified and introduced by the author. In this article, we summarize these rock art areas in Iranian Kurdistan.

  12. Rock Art in Kurdistan Iran

    OpenAIRE

    Jamal Lahafian

    2013-01-01

    Kurdistan, with great potential and prehistoric resources, has numerous petroglyphs in different areas of the province. During the last 14 years of extensive field study, more than 30 sites of rock art have been identified and introduced by the author. In this article, we summarize these rock art areas in Iranian Kurdistan.

  13. Geochronologic and geochemical constraints of the petrogenesis of Permian mafic dykes in the Wuding area, SW China: Implications for Fe-Ti enrichment in mafic rocks in the ELIP

    Science.gov (United States)

    Fan, Hong-Peng; Zhu, Wei-Guang; Bai, Zhong-Jie; Yang, Yi-Jin

    2017-02-01

    Mafic dykes are widely distributed and well preserved in the Wuding area, SW China. The dykes are composed of fine-grained diabases, which are further subdivided into two groups (Group I and Group II). The rocks from Group I have relatively higher MgO (4.95-6.16 wt%) and lower TiO2 (2.26-2.78 wt%) contents than those from the Group II rocks (MgO = 4.04-4.58 wt%; TiO2 = 4.09-4.55 wt%). Two baddeleyite ages of 264 ± 3 Ma and 256 ± 5 Ma from the Wuding dykes suggest that the ages of these dykes are similar to the plutonic bodies and the associated volcanic rocks of the Emeishan large igneous province (ELIP). The compositions and isotopic signatures of the dykes are also similar to those of the ELIP volcanic rocks, indicating derivation from the same magmatic event at 260 Ma. The primary melts of the Wuding dykes were originated by partial melting of a long-term depleted OIB-like mantle source. The Group I dykes were mainly formed by wallrock assimilation and fractional crystallization processes. The magmas parental to the Group II rocks were much more evolved than the magma parental to the Group I rocks and probably produced by wallrock assimilation and fractional crystallization of the parent magma of the Group I rocks. The increasing enrichment of Fe and Ti from the Group I to the Group II rocks were attributed to a fractional crystallization process which may be an epitome of enrichment of Fe and Ti in the Fe-Ti rich mafic intrusions of the ELIP.

  14. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  15. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  16. 黔中-渝南石炭纪铝土矿含矿岩系中的海相沉积特征%Characteristics of marine deposits of the bauxite-bearing rock series in central Guizhou-southern Chongqing area

    Institute of Scientific and Technical Information of China (English)

    刘平; 廖友常; 张雅静

    2015-01-01

    黔中—渝南地区于紫云运动初期的泥盆纪末已准平原化,在石炭纪铝土矿含矿岩系沉积过程中,含矿岩系下段(铁质−粘土岩段)主要为近海湖泊相,含矿岩系上段(铝质岩段)为近海平原相。在这种大环境前提下,经常会受到海泛与强风暴潮的影响与改造,使得主要是陆相环境沉积形成的铝土矿含矿岩系中,含有少量海相大化石(腕足类)和微体生物化石(疑源类和牙形石);另在下段和上段岩矿层间,时夹海相碳酸盐岩透镜体,具明显海相沉积特征。以上表明,黔中—渝南石炭系铝土矿含矿岩系形成环境具有显著的多样性和复杂性,而非单纯的陆相沉积环境所能概括的。%The central Guizhou-southern Chongqing area had experienced peneplanation at the beginning of Ziyun Movement before the end of the Devonian. In the deposition process of the Carboniferous bauxite-bearing rock series, the lower bauxite-bearing rock series (iron-clay rock) was mostly offshore lake facies, and the upper bauxite-bearing rock series (aluminous rock) was mostly offshore plain facies. In this environment, the influence and reformation of ingression and strong storm surge were frequent. Thus, there exsited a few marine plant fossils (brachiopoda) and marine microfossils (acritarch and conodont) in the bauxite-bearing rock series, which mostly deposited in a continental environment. And there were less marine carbonate lens in the lower (iron-clay rock segment) and the upper (aluminiferous rock segment) bauxite-bearing rock series, suggesting obvious characteristics of marine deposition. All these phenomena indicate that the formation environment of the bauxite-bearing rock series in central Guizhou-southern Chongqing area was very diverse and complex. It was affected not only by continental sedimentary environment but also by other factors.

  17. Study on Petrological Characteristics and Cycle of Volcano Rocks in Qingshuigou Area of Western Qilian Mountain%西祁连清水沟地区火山岩岩石学特征及旋回研究

    Institute of Scientific and Technical Information of China (English)

    李国涛; 孙丽莎; 翟孝志; 孙晓亮; 吴洪彬

    2016-01-01

    Cambrian volcano rocks in Dangjinshan Qingshuigou area in western Qilian mountain developed in vol⁃cano rock group in Cambrian Lapeiquan group. Distribution characteristics of the volcano rock and petrological char⁃acteristics have been studied and divided into 3 types of volcano rock facies, such as eruption facies, sedimentary facies and effusive facies. Volcano eruption cycles have been studied as well. The formation evolution characteristics in Dangjinshan area has been revealed. It has a certain guiding significance for the comparison of volcanic rock are⁃as and the recovery of volcanic mechanism.%西祁连当金山清水沟一带的寒武纪火山岩发育在寒武纪拉配泉岩群火山岩组。对该火山岩分布特征和岩石学特征进行了研究,划分了3类火山岩岩相:爆发相、沉积相、喷溢相,并对火山岩喷发旋回进行了研究,揭示了当金山地区地层演化特征,对火山岩区域对比及火山机构恢复具有一定的指导意义。

  18. Zircon SHRIMP dating of sodium alkaline rocks from Maomaogou area of Huili County in Panxi,SW China and its geological implications

    Institute of Scientific and Technical Information of China (English)

    LIU Hongying; XIA Bin; ZHANG Yuquan

    2004-01-01

    Alkali-feldspar syenites from the Maomaogou area of Huili County in Panxi of Sichuan Province, SW China are sodium alkaline rocks, the minerals of which are mainly composed of calcic ferroaugite, ferroamphibole and biotite. Most of the zircons (>80%) selected for SHRIMP U-Pb dating are magmatic compound zircons and they have relict inner cores and growing outer shells. The age of zircon SHRIMP U-Pb dating is 224±8 Ma, suggesting that the Maomaogou alkali-feldspar syenite was formed in the late Triassic period. At the same time, two old age periods of relict cores of zircon are determined, they are the Archean age (2692-2818 Ma) and Neoproterozoic age (622-691 Ma),respectively. These periods indicate that the cores derived from the crystal basement. Furthermore, the Archean age of zircon provides the first reliable SHRIMP U-Pb zircon dating evidence of >2.8 Ga basement in the Xikang-Yunnan Axis of southwest China.

  19. Petrogenesis and zircon U-Pb dating of skarnified pyroxene-bearing dioritic rocks in Bisheh area, south of Birjand, eastern Iran

    Directory of Open Access Journals (Sweden)

    Malihe Nakhaei

    2014-10-01

    Full Text Available Introduction The study area is located 196 km south of Birjand in eastern border of the Lut block Berberian and King, 1981 in eastern Iran between 59°05′35" and 59°09′12" E longitude and 31°42′29" and 31°44′13" N latitude. The magmatic activity in the Lut block began in the middle Jurassic such as Kalateh Ahani, Shah Kuh and Surkh Kuh granitoids that are among the oldest rocks exposed within the Lut block (Esmaeily et al., 2005; Tarkian et al., 1983; Moradi Noghondar et al., 2011-2012. Eastern Iran, and particularly the Lut block, has great potential for different types of mineralization as skarnification in Bisheh area which has been studied in this paper. The goal of this study is to highlight the geochronology, geochemistry of major and trace elements, Rb-Sr, Sm-Nd isotopes for skarnified pyroxene-bearing diorites. Materials and methods Major element compositions of thirteen samples were determined by wavelength-dispersive X-ray fluorescence (XRF spectrometry, using fused discs and the Phillips PW 1410 XRF spectrometer at Ferdowsi University, Mashhad, Iran. These samples were analysed for trace elements using inductively coupled plasma-mass spectrometry (ICP-MS in the Acme Analytical Laboratories, Vancouver, British Columbia, Canada. Zircon grains were separated from pyroxene diorite porphyrys using heavy liquid and magnetic techniques at the Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan. Zircon U-Pb dating was performed by laser ablation-inductively-coupled plasma-mass spectrometry (LA-ICP-MS, using an Agilent 7500 s machine and a New Wave UP213 laser ablation system, equipped at the Dr Shen-Su Sun memorial laboratory in the Department of Geosciences, National Taiwan University, Taiwan. Strontium and Nd isotopic analyses were performed on a six-collector Finnigan MAT 261 thermal-ionization mass spectrometer at the University of Colorado, Boulder, Colorado, United States. 87Sr/86Sr ratios were determined using four

  20. Deformation Along the Southeast Extension of the Lake Mead Fault System Evaluated with Paleomagnetic Data From Miocene Igneous Rocks, Hoover Dam area, Nevada and Arizona

    Science.gov (United States)

    Geissman, J. W.

    2002-12-01

    At and near Hoover Dam, southeast of Las Vegas, Cenozoic left-slip offset along the NE-SW trending Lake Mead fault system (LMFS) has resulted in the apparent rotation of structures and total displacement of up to 65 km. Defining any rotation of blocks within and near the LMFS is critical to assessing the kinematics of strike-slip faulting and attending extension. Paleomagnetic data from Miocene volcanic and some sedimentary rocks and intrusions (over 160 sites) deposited on Precambrian basement show that part of the Hoover Dam locality has experienced counterclockwise rotation . The middle Miocene (ca. 14.2 Ma)Tuff of Hoover Dam (THD)(sampled at over 90 sites) yields a well-grouped characteristic magnetization (ChRM); about 5 km south and east of the dam, gently east-dipping, north-striking rocks of the THD yield a corrected ChRM of moderate positive inclination and northwest declination (D=324.8°, I=27.4°, a95=10.7°, k=24, N=9 sites). Structural corrections, based on compaction fabrics in the THD are consistent with stratigraphic contacts. The anomalous shallow inclination for the THD ChRM implies that it was emplaced over a short period of time during a field instability. contact and conglomerate test results are interpreted to show that the THD ChRM is primary. Corrected data from north and west of the dam (D=289.7°, I=30.2°,a95=8.6°,k=32, N=10) are interpreted to indicate about 35° of counterclockwise rotation (R= -35.1°, delR= 12.4, F= -2.8°, delF = 10.8, relative to data from south of the dam) of crust across the dam site, consistent with progressive changes in strike of tilted fault blocks. The transition from apparently unrotated crust to rotated crust occurs over a zone about 1 km wide, where blocks of THD and older strata have been tilted up to 50°, probably concurrent with rotation. Rotation of crust northwest of Hoover Dam may reflect differential extension northwest of the LMFS (e.g.,River Mountains area) as strain is partitioned into west to

  1. Challenges within Monitoring and Risk-Oriented Analysis of Precipitation- and Hydraulic- Coupled Catastrophic Rock- and Soil-Collapses at Urban and Infrastructural Alpine Areas

    Science.gov (United States)

    Scheikl, M.

    2007-05-01

    Within the past years we investigated several catastrophic soil- and rock-slides along infrastructural and urban areas which are coupled to extreme weather phenomena. This contribution shall show examples, triggered by catastrophic rain-falls and anthropogenic influence. Further, the stress-field between the compliance with legal and economical requirements and the rising frequency of weather induced events shall be discussed from the geoengineers point of view. In the past, engineers were strictly confronted with the detailed geological and geomechanical or numerical analysis of the slope failures. Since the past role of the engineer as inviolable decision leader is increasingly weakened, due to economic control obligations - mostly operated from the far desk - new ways of conviction work had to be developed as well as effective forecasting and monitoring instruments. For this reason the requirement to engineers, regarding the ability to work multidisciplinary and to find more exact models, is risen, which is to be seen positively. In order to fulfill the increasing justification-requires when planning counter measures, several technical and economical aspects are to be described quantitatively now. This quantitative description is the basis for risk- analysis, which has to contain beside other aspects following: a) The shift of the probability of extreme events b) The expected harm at humans at the scenario put to reason c) The expected damage at structures d) The expected super-ordinate economical harm e) The expected costs of counter-measure variants f) The variant related residual risk, expressed in probable occurring costs While the description of the first aspect a) is mainly a geotechnical challenge, which is connected to very detailed knowledge of the slope-failure characteristic, triggering mechanisms as well as related historical and future meteorological data, the aspects c) and e) concern exact technical cost investigations. The real challenges are

  2. Reassessment of petrogenesis of Carboniferous–Early Permian rift-related volcanic rocks in the Chinese Tianshan and its neighboring areas

    Directory of Open Access Journals (Sweden)

    Linqi Xia

    2012-07-01

    Full Text Available The Carboniferous−Early Permian rift-related volcanic successions, covering large areas in the Chinese Tianshan and its adjacent areas, make up a newly recognized important Phanerozoic large igneous province in the world, which can be further divided into two sub-provinces: Tianshan and Tarim. The regional unconformity of Lower Carboniferous upon basement or pre-Carboniferous rocks, the ages (360–351 Ma of the youngest ophiolite and the peak of subduction metamorphism of high pressure–low temperature metamorphic belt and the occurrence of Ni-Cu-bearing mafic-ultramafic intrusion with age of ∼352 Ma and A-type granite with age of ∼358 Ma reveal that the final closure of the Paleo-Asian Ocean might take place in the Early Mississippian. Our summation shows that at least four criteria, being normally used to identify ancient asthenosphere upwelling (or mantle plumes, are met for this large igneous province: (1 surface uplift prior to magmatism; (2 being associated with continental rifting and breakup events; (3 chemical characteristics of asthenosphere (or plume derived basalts; (4 close links to large-scale mineralization and the uncontaminated basalts, being analogous to those of many “ore-bearing” large igneous provinces, display Sr-Nd isotopic variations between plume and EM1 geochemical signatures. These suggest that a Carboniferous asthenosphere upwelling and an Early Permian plume played the central role in the generation of the Tianshan–Tarim (central Asia large igneous province.

  3. ROCK ON

    National Research Council Canada - National Science Library

    Thomas Grose

    2014-01-01

    ..., however, was music - especially the high-pitched sounds of pop and rock, which boosted energy output by up to 40 percent. By contrast, classical music's lower pitches barely raised effectiveness. O...

  4. Hydrothermal alteration at the Roosevelt Hot Springs Thermal Area, Utah: modal mineralogy, and geochemistry of sericite, chlorite, and feldspar from altered rocks, Thermal Power Company well Utah State 14-2

    Energy Technology Data Exchange (ETDEWEB)

    Ballantyne, J.M.

    1978-11-01

    Sericites, chlorites, feldspars, biotite and hornblende from hydrothermally altered rocks at several depths in Thermal Power Company well Utah State 14-2, Roosevelt Hot Springs Thermal Area, Utah, have been analyzed using the electron microprobe. Sericites and ferromagnesian minerals have been analyzed for 12 major elements, and feldspars for 3. The results have been used, along with whole rock chemical analyses, to computer calculate modal mineralogy for samples from the drillhole. Calculated modes for hydrothermal minerals are in reasonable agreement with observations from thin sections.

  5. Rock types and ductile structures on a rock domain basis, and fracture orientation and mineralogy on a deformation zone basis. Preliminary site description. Forsmark area - version 1.2

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Michael [Geological Survey of Sweden, Uppsala (Sweden); Forssberg, Ola [Golder Associates AB, Uppsala (Sweden)

    2006-09-15

    This report presents the results of the analysis of base geological data in order to establish the dominant rock type, the subordinate rock types and the orientation of ductile mineral fabrics within each rock domain included in the regional geological model, version 1.2. An assessment of the degree of homogeneity of each domain is also provided. The analytical work has utilised the presentation of data in the form of histograms and stereographic projections. Fisher means and K values or best-fit great circles and corresponding pole values have been calculated for the ductile structural data. These values have been used in the geometric modelling of rock domains in the regional model, version 1.2. Furthermore, all analytical results have been used in the assignment of properties to rock domains in this model. A second analytical component reported here addresses the orientation and mineralogy of fractures in the deterministic deformation zones that are included in the regional geological model, version 1.2. The analytical work has once again utilised the presentation of data in the form of histograms and stereographic projections. Fisher means and K values are presented for the orientation of fracture sets in the deterministic deformation zones that have been identified with the help of new borehole data. The frequencies of occurrence of different minerals along the fractures in these deformation zones as well as the orientation of fractures in the zones, along which different minerals occur, are also presented. The results of the analyses have been used in the establishment of a conceptual structural model for the Forsmark site and in the assignment of properties to deterministic deformation zones in model version 1.2.

  6. Petrology and physical conditions of metamorphism of calcsilicate rocks from low- to high-grade transition area, Dharmapuri District, Tamil Nadu

    Science.gov (United States)

    Narayana, B. L.; Natarajan, R.; Govil, P. K.

    1988-01-01

    Calc-silicate rocks comprising quartz, plagioclase, diopside, sphene, scapolite, grossularite-andradite and wollastonite occur as lensoid enclaves within the greasy migmatitic and charnockitic gneisses of the Archaean amphibolite- to granulite-facies transition zone in Dharmapuri district, Tamil Nadu. The calc-silicate rocks are characterized by the absence of K-feldspar and primary calcite, presence of large modal quartz and plagioclase and formation of secondary garnet and zoisite rims around scapolite and wollastonite. The mineral distributions suggest compositional layering. The chemical composition and mineralogy of the calc-silicate rocks indicate that they were derived from impure silica-rich calcareous sediments whose composition is similar to that of pelite-limestone mixtures. From the mineral assemblages the temperature, pressure and fluid composition during metamorphism were estimated. The observed mineral reaction sequences require a range of X sub CO2 values demonstrating that an initially CO2-rich metamorphic fluid evolved with time towards considerably more H2O-rich compositions. These variations in fluid composition suggest that there were sources of water-rich fluids external to the calc-silicate rocks and that mixing of these fluids with those of calc-silicate rocks was important in controlling fluid composition in calc-silicate rocks and some adjacent rock types as well.

  7. 南海北部深水区烃源岩形成和分布研究%The Formation and Distribution of Source Rocks for Deep Water Area in the Northern of South China Sea

    Institute of Scientific and Technical Information of China (English)

    李友川; 米立军; 张功成; 傅宁; 孙玉梅

    2011-01-01

    .Because of the influence of the Paleo-pearl River,coal-bearing source rock of Enping Formation distribute relatively widespread and stable in the Pearl River Mouth basin.But there is no large river system,and fan-delta is the main type of delta,so coal-bearing source rock of Yacheng Formation distributed relatively limited in Qiongdongnan basin.The formation of marine source rocks is influenced by the quantity of terrestrial organic matter and accumulation and reservation of organic matter.Because of the difference of paleo-geography condition between the Pearl River Mouth basin and Qiongdongnan basin,origin of terrestrial organic matter in the Pearl River Mouth basin is much more abundant than Qiongdongnan basin,and the content of total organic carbon for marine source rock in the Pearl River Mouth basin is higher than the same geological time source rocks in Qiongdongnan basin.Because the supply of terrestrial organic matter decrease from land to ocean,so the organic matter content of marine source rock also lower from land to ocean.Seen from the distribution of source rocks in north of South China Sea,source rocks with relative high organic matter content mainly distributed in the surrounding area of basin or depression,they are mainly composed of coal-bearing source rock,also include some marine source rock with abundant organic matter,but the organic matter content is popularly low in the depocenter of basin or depression,the surrounding area of basin or depression is more profit for oil and gas exploration.

  8. Effect of ultramafic intrusions and associated mineralized rocks on the aqueous geochemistry of the Tangle Lakes Area, Alaska: Chapter C in Studies by the U.S. Geological Survey in Alaska, 2011

    Science.gov (United States)

    Wang, Bronwen; Gough, Larry P.; Wanty, Richard B.; Lee, Gregory K.; Vohden, James; O’Neill, J. Michael; Kerin, L. Jack

    2013-01-01

    Stream water was collected at 30 sites within the Tangle Lakes area of the Delta mineral belt in Alaska. Sampling focused on streams near the ultramafic rocks of the Fish Lake intrusive complex south of Eureka Creek and the Tangle Complex area east of Fourteen Mile Lake, as well as on those within the deformed metasedimentary, metavolcanic, and intrusive rocks of the Specimen Creek drainage and drainages east of Eureka Glacier. Major, minor, and trace elements were analyzed in aqueous samples for this reconnaissance aqueous geochemistry effort. The lithologic differences within the study area are reflected in the major-ion chemistry of the water. The dominant major cation in streams draining mafic and ultramafic rocks is Mg2+; abundant Mg and low Ca in these streams reflect the abundance of Mg-rich minerals in these intrusions. Nickel and Cu are detected in 84 percent and 87 percent of the filtered samples, respectively. Nickel and Cu concentrations ranged from Ni rock fractionation profiles for the aqueous samples were light rare earth element depleted, with negative Ce and Eu anomalies, indicating fractionation of the REE during weathering. Fractionation patterns indicate that the REE are primarily in the dissolved, as opposed to colloidal, phase.

  9. Groundwater-quality data in the Bear Valley and Selected Hard Rock Areas study unit, 2010: Results from the California GAMA Program

    Science.gov (United States)

    Mathany, Timothy M.; Belitz, Kenneth

    2013-01-01

    Groundwater quality in the 112-square-mile Bear Valley and Selected Hard Rock Areas (BEAR) study unit was investigated by the U.S. Geological Survey (USGS) from April to August 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The BEAR study unit was the thirty-first study unit to be sampled as part of the GAMA-PBP. The GAMA Bear Valley and Selected Hard Rock Areas study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer system and to facilitate statistically consistent comparisons of untreated groundwater quality throughout California. The primary aquifer system is defined as the zones corresponding to the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the BEAR study unit. Groundwater quality in the primary aquifer system may differ from the quality in the shallow or deep water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. In the BEAR study unit, groundwater samples were collected from two study areas (Bear Valley and Selected Hard Rock Areas) in San Bernardino County. Of the 38 sampling sites, 27 were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the primary aquifer system in the study unit (grid sites), and the remaining 11 sites were selected to aid in the understanding of the potential groundwater-quality issues associated with septic tank use and with ski areas in the study unit (understanding sites). The groundwater samples were analyzed for organic constituents (volatile organic compounds [VOCs], pesticides and

  10. Corrective Action Investigation Plan for Corrective Action Unit 230: Area 22 Sewage Lagoons and Corrective Action Unit 320: Area 22 Desert Rock Air port Strainer Box, Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Department of Energy, Nevada Operations Office

    1999-06-10

    This Corrective Action Investigation Plan contains the US Department of Energy, Nevada Operation Office's approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 230/320 under the Federal Facility Agreement and Consent Order. Corrective Action Unit 230 consists of Corrective Action Site (CAS) 22-03-01, Sewage Lagoon; while CAU 320 consists of CAS 22-99-01, Strainer Box. These CAUs are referred to as CAU 230/320 or the Sewage Lagoons Site. The Sewage Lagoons Site also includes an Imhoff tank, sludge bed, and associated buried sewer piping. Located in Area 22, the site was used between 1951 to 1958 for disposal of sanitary sewage effluent from the historic Camp Desert Rock Facility at the Nevada Test Site in Nevada. Based on site history, the contaminants of potential concern include volatile organic compounds (VOCs), semivolatile organic compounds, total petroleum hydrocarbons (TPH), and radionuclides. Vertical migration is estimated to be less than 12 feet below ground surface, and lateral migration is limited to the soil immediately adjacent to or within areas of concern. The proposed investigation will involve a combination of field screening for VOCs and TPH using the direct-push method and excavation using a backhoe to gather soil samples for analysis. Gamma spectroscopy will also be conducted for waste management purposes. Sampling locations will be biased to suspected worst-case areas including the nearby sludge bed, sewage lagoon inlet(s) and outlet(s), disturbed soil surrounding the lagoons, surface drainage channel south of the lagoons, and the area near the Imhoff tank. The results of this field investigation will support a defensible evaluation of corrective action alternatives in the corrective action decision document.

  11. Corrective Action Investigation Plan for Corrective Action Unit 230: Area 22 Sewage Lagoons and Corrective Action Unit 320: Area 22 Desert Rock Airport Strainer Box, Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    US DOE/Nevada Operations Office

    1999-06-10

    This Corrective Action Investigation Plan contains the U.S. Department of Energy, Nevada Operation Office's approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 230/320 under the Federal Facility Agreement and Consent Order. Corrective Action Unit 230 consists of Corrective Action Site (CAS) 22-03-01, Sewage Lagoon; while CAU 320 consists of CAS 22-99-01, Strainer Box. These CAUs are referred to as CAU 230/320 or the Sewage Lagoons Site. The Sewage Lagoons Site also includes an Imhoff tank, sludge bed, and associated buried sewer piping. Located in Area 22, the site was used between 1951 to 1958 for disposal of sanitary sewage effluent from the historic Camp Desert Rock Facility at the Nevada Test Site in Nevada. Based on site history, the contaminants of potential concern include volatile organic compounds (VOCs), semivolatile organic compounds, total petroleum hydrocarbons (TPH), and radionuclides. Vertical migration is estimated to be less than 12 feet below ground surface, and lateral migration is limited to the soil immediately adjacent to or within areas of concern. The proposed investigation will involve a combination of field screening for VOCs and TPH using the direct-push method and excavation using a backhoe to gather soil samples for analysis. Gamma spectroscopy will also be conducted for waste management purposes. Sampling locations will be biased to suspected worst-case areas including the nearby sludge bed, sewage lagoon inlet(s) and outlet(s), disturbed soil surrounding the lagoons, surface drainage channel south of the lagoons, and the area near the Imhoff tank. The results of this field investigation will support a defensible evaluation of corrective action alternatives in the corrective action decision document.

  12. Geochemistry and spatial distribution of late-Paleozoic mafic volcanic rocks in the surrounding areas of the Gonghe Basin: Implications for Majixueshan triple-junction and east Paleotethyan archipelagic ocean

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The late-Paleozoic mafic volcanic rocks occurring in the surrounding areas of the Gonghe basin are distributed in the A'nyêmaqên ophiolite zone, Zongwulong tectonic zone and Kuhai-Saishitang volcanic zone. The mafic volcanics in the A'nyêmaqên zone formed an ancient ridge-centered hotspot around the Majixueshan OIB, the Kuhai-Saishitang mafic rocks consist of E-MORB and continental rift basalts and the Zongwulong volcanic rocks are enriched N-MORB. The regionally low Nb/U and Ce/Pb ratios reflect the influence of the OIB material on the mafic magma source. From geochemistry, spatial distribution and tectonic relationship of the mafic rocks, an ancient triple-junction centered at the Majixueshan can be inferred. The existence of the Kuhai-Saishitang aulacogen may have provided a tectonic channel for the Majixueshan OIB materials metasomatizing the magma source for the Zongwulong rocks. The formation of the triple-junction and the rifting of the Zongwulong zone have separated the orogens and massifs in the region.

  13. Rock-shells (Thais clavigera) as an indicator of As, Cu, and Zn contamination on the Putai Coast of the black-foot disease area in Taiwan.

    Science.gov (United States)

    Han, B C; Jeng, W L; Jeng, M S; Kao, L T; Meng, P J; Huang, Y L

    1997-05-01

    This study presents the distribution of arsenic (As), copper (Cu), and zinc (Zn) in various seafoods-oysters (Crassostrea gigas), false fusus (Hemifuscus tuba), venus clams (Cyclina sineasis), green mussels (Perna viridis), blood clams (Arca granosa), flounders (Psettodes erumei), and rock-shells (Thais clavigera) collected from the Putai coast of the black-foot disease (BFD) area in Taiwan. Special attention is paid to evaluate the relationships among As, Cu, and Zn and effect of body size on metal concentration in Thais clavigera. Maximum Zn and Cu geometric mean (GM) concentrations (GM = 615 and 376 microg/g, dry wt, respectively) are found in oysters (Crassostrea gigas), and the values are much higher than those of the other organisms by about 1.7-208 and 1.8-375 times, respectively. Similarly, Thais clavigera has a high capacity for accumulating Cu and Zn collected from the same location. One interesting point is that relatively high As concentrations (GM = 65.7 microg/g, dry wt) in Thais clavigera are found as compared with those in other organisms (range from GM = 2.37 to 40.2 microg/g, dry wt). The As concentrations are significantly higher in Thais clavigera (1.62-27.7 times) than those in other organisms (p shell length show linear relationships. The result indicates that large individuals have higher contents of Cu, Zn and As, and have slopes of 1.58, 1.38, and 1.34, respectively. In addition, metal concentrations against shell length for all animal sizes also indicate that Cu, Zn and As have slopes of 1.92, 1.18, and 1.11, respectively. In conclusion, Thais clavigera has a high capactiy for accumulating As, Cu, and Zn and is a potential bioindicator for monitoring As, Cu and Zn.

  14. Fluoride abundance and controls in fresh groundwater in Quaternary deposits and bedrock fractures in an area with fluorine-rich granitoid rocks.

    Science.gov (United States)

    Berger, Tobias; Mathurin, Frédéric A; Drake, Henrik; Åström, Mats E

    2016-11-01

    This study focuses on fluoride (F(-)) concentrations in groundwater in an area in northern Europe (Laxemar, southeast Sweden) where high F(-) concentrations have previously been found in surface waters such as streams and quarries. Fluoride concentrations were determined over time in groundwater in the Quaternary deposits ("regolith groundwater"), and with different sampling techniques from just beneath the ground surface to nearly -700m in the bedrock (fracture) groundwater. A number of potential controls of dissolved F(-) were studied, including geological variables, mineralogy, mineral chemistry and hydrology. In the regolith groundwater the F(-) concentrations (0.3-4.2mg/L) were relatively stable over time at each sampling site but varied widely among the sampling sites. In these groundwaters, the F(-) concentrations were uncorrelated with sample (filter) depth and the water table in meters above sea level (masl), with the thicknesses of the groundwater column and the regolith, and with the distribution of soil types at the sampling sites. Fluoride concentrations were, however, correlated with the anticipated spatial distribution of erosional material (till) derived from a F-rich circular granite intrusion. Abundant release of F(-) from such material is thus suggested, primarily via dissolution of fluorite and weathering of biotite. In the fresh fracture groundwater, the F(-) concentrations (1.2-7.4mg/L) were generally higher than in the regolith groundwater, and were uncorrelated with depth and with location relative to the granite intrusion. Two mechanisms explaining the overall high F(-) levels in the fracture groundwater were addressed. First, weathering/dissolution of fluorite, bastnäsite and apophyllite, which are secondary minerals formed in the fractures during past hydrothermal events, and biotite which is a primary mineral exposed on fracture walls. Second, long water-residence times, favoring water-rock interaction and build-up of high dissolved F

  15. Source rock

    OpenAIRE

    Abubakr F. Makky; Mohamed I. El Sayed; Ahmed S. Abu El-Ata; Ibrahim M. Abd El-Gaied; Mohamed I. Abdel-Fattah; Zakaria M. Abd-Allah

    2014-01-01

    West Beni Suef Concession is located at the western part of Beni Suef Basin which is a relatively under-explored basin and lies about 150 km south of Cairo. The major goal of this study is to evaluate the source rock by using different techniques as Rock-Eval pyrolysis, Vitrinite reflectance (%Ro), and well log data of some Cretaceous sequences including Abu Roash (E, F and G members), Kharita and Betty formations. The BasinMod 1D program is used in this study to construct the burial history ...

  16. Overstep and imbrication along a sidewall ramp and its relationship to a hydrocarbon play in Tournaisian rocks of the Moncton Basin : the Peek Creek section, Albert Mines area, southeastern New Brunswick

    Energy Technology Data Exchange (ETDEWEB)

    Park, A.F.; Kieghley, D.G.; Wilson, P. [New Brunswick Univ., Fredericton, NB (Canada). Dept. of Geology; St Peter, C.J. [New Brunswick Dept. of Natural Resources and Energy, Fredericton, NB (Canada). Geological Surveys Branch

    2010-09-15

    This paper characterized the geological stratigraphic and structural relationships of the Peek Creek section of the Albert Mines area in southeastern New Brunswick with reference to the local absence of the nearby petroleum system, which has direct ramifications for petroleum exploration. The lithostratigraphic correlation in the Albert Mines area was discussed along with the structures produced during one episode of inversion along part of the Moncton Basin south margin, which involves Horton and Sussex group rocks included in thrust-bounded panels along the trace of the basement-bounding Caledonia Fault. The Horton Group contains the oil-gas play. Therefore, the explanation of this geometry and the local absence of the petroleum system have significance for exploration efforts. The paper focused on the relationships seen in the Peck Creek section located just west of Albert Mines. The Peek Creek section at the southern margin of the Moncton Basin preserves a well-exposed late Tournaisian Sussex Group succession with the bounding crystalline rocks of the Caledonia Uplift. Of particular interest was the relationship between deformation of the rocks in the Horton and Sussex groups and the unconformably overlying Hillsborough Formation. This section was subjected to a thrust-related deformation after the deposition of the Sussex Group but before the deposition of the Hillsborough Formation. The Sub-Hillsborough Formation unconformity and the Caledonia Fault, which impinge on the Peek Creek area, were also characterized along with the geometry and kinematics of the study area. 35 refs., 9 figs.

  17. Characterization of the volcanic and hypabissal rocks of the Paleoproterozoic Iricoumé Group in the Pitinga region and Balbina Lake area, Amazonian Craton, Brazil: Petrographic distinguishing features and emplacement conditions

    Science.gov (United States)

    Simões, Matheus Silva; Almeida, Marcelo Esteves; de Souza, Antonio Gilmar Honorato; da Silva, Desaix Paulo Balieiro; Rocha, Paloma Gabriela

    2014-10-01

    The Iricoumé Group (1.897 to 1.875 Ma) is a widespread volcanic sequence in the Amazonian Craton, South American Platform. In the Pitinga region, it consists of acidic to intermediate ignimbrites with cogenetic surge and ash-fall deposits associated to hypabissal and effusive acidic rocks. In the Balbina Lake area it consists of acidic to intermediate effusive rocks, crystal-rich ignimbrites and pumice-rich ignimbrites. Detailed petrographic studies of phenocrysts and crystal fragments provided characterization and distinctive features of pyroclastic, effusive and hypabissal rocks. The phenocrysts of hypabissal rocks were affected by high temperature resorption and flow-related physical fragmentation, the effusive rocks can have a considerable content of crystal fragments due to intense dissolution and fragmentation of the phenocrysts and the pyroclastic rocks crystal fragments are generated mainly by decompression mechanic fragmentation. Dissolution and resorption of quartz and feldspar crystals may have acted at pressure conditions between 500 MPa and 100 MPa, in response to rapid decompression in the magma ascent. The viscosity values of 7,5-10 log η (Pa s) for anhydrous conditions decrease exponentially with estimated water addition. The amount of phenocrysts and their intratelluric character in the volcanic units of Iricoumé Group can be related to a magma chamber with high content of crystals. We suggest that even with the addition of water in the magma, the viscosities had a drastic increase with progressive crystal growth due to the viscosity dependence on the solid fraction and the deposits were generated by the extrusion of viscous lava and pyroclastic flows.

  18. Questa Baseline and Pre-Mining Ground-Water Quality Investigation. 19. Leaching Characteristics of Composited Materials from Mine Waste-Rock Piles and Naturally Altered Areas near Questa, New Mexico

    Science.gov (United States)

    Smith, Kathleen S.; Hageman, Philip L.; Briggs, Paul H.; Sutley, Stephen J.; McCleskey, R. Blaine; Livo, K. Eric; Verplanck, Philip L.; Adams, Monique G.; Gemery-Hill, Pamela A.

    2007-01-01

    The goal of this study is to compare and contrast the leachability of metals and the acidity from individual mine waste-rock piles and natural erosional scars in the study area near Questa, New Mexico. Surficial multi-increment (composite) samples less than 2 millimeters in diameter from five waste-rock piles, nine erosional-scar areas, a less-altered site, and a tailings slurry-pipe sample were analyzed for bulk chemistry and mineralogy and subjected to two back-to-back leaching procedures. The first leaching procedure, the U.S. Geological Survey Field Leach Test (FLT), is a short-duration leach (5-minute shaking and 10-minute settling) and is intended to leach readily soluble materials. The FLT was immediately followed by an 18-hour, end-over-end rotation leaching procedure. Comparison of results from the back-to-back leaching procedures can provide information about reactions that may take place upon migration of leachates through changing geochemical conditions (for example, pH changes), both within the waste-rock and scar materials and away from the source materials. For the scar leachates, the concentrations of leachable metals varied substantially between the scar areas sampled. The scar leachates have low pH (pH 3.2-4.1). Under these low-pH conditions, cationic metals are solubilized and mobile, but anionic species, such as molybdenum, are less soluble and less mobile. Generally, metal concentrations in the waste-rock leachates did not exceed the upper range of those metal concentrations in the erosional-scar leachates. One exception is molybdenum, which is notably higher in the waste-rock leachates compared with the scar leachates. Most of the waste-rock leachates were at least mildly acidic (pH 3.0-6.2). The pH values in the waste-rock leachates span a large pH range that includes some pH-dependent solubility and metal-attenuation reactions. An increase in pH with leaching time and agitation indicates that there is pH-buffering capacity in some of the

  19. Rock Paintings.

    Science.gov (United States)

    Jones, Julienne Edwards

    1998-01-01

    Discusses the integration of art and academics in a fifth-grade instructional unit on Native American culture. Describes how students studied Native American pictographs, designed their own pictographs, made their own tools, and created rock paintings of their pictographs using these tools. Provides a list of references on Native American…

  20. Ayers Rock

    Institute of Scientific and Technical Information of China (English)

    王慧茹

    2002-01-01

    Ayers Rock is right in the centre of Australia.It's nearly two thousand kilometres______Sydney.So we flew most of the way.h was rather cloudy______But after we left the mountains behind us, there was hardly a cloud in thesky.

  1. Intellektuaalne rock

    Index Scriptorium Estoniae

    2007-01-01

    Briti laulja-helilooja ja näitleja Toyah Willcox ning Bill Rieflin ansamblist R.E.M. ja Pat Mastelotto King Krimsonist esinevad koos ansamblitega The Humans ja Tuner 25. okt. Tallinnas Rock Cafés ja 27. okt Tartu Jaani kirikus

  2. Intellektuaalne rock

    Index Scriptorium Estoniae

    2007-01-01

    Briti laulja-helilooja ja näitleja Toyah Willcox ning Bill Rieflin ansamblist R.E.M. ja Pat Mastelotto King Krimsonist esinevad koos ansamblitega The Humans ja Tuner 25. okt. Tallinnas Rock Cafés ja 27. okt Tartu Jaani kirikus

  3. Changes in composition and pore space of sand rocks in the oil water contact zone (section YU1 3-4, Klyuchevskaya area, Tomsk region)

    Science.gov (United States)

    Nedolivko, N.; Perevertailo, T.; Pavlovec, T.

    2016-09-01

    The article provides an analysis of specific features in changes of rocks in the oil water contact zone. The object of study is the formation YU1 3-4 (J3o1) of Klyuchevskaya oil deposit (West Siberian oil-gas province, Tomsk region). The research data allow the authors to determine vertical zoning of the surface structure and identify the following zones: oil saturation (weak alteration), bitumen-content dissolution, non-bitumen-content dissolution, cementation, including rocks not affected by hydrocarbon deposit. The rocks under investigation are characterized by different changes in composition, pore space, as well as reservoir filtration and volumetric parameters. Detection of irregularity in distribution of void- pore space in oil-water contact zones is of great practical importance. It helps to avoid the errors in differential pressure drawdown and explain the origin of low-resistivity collectors.

  4. ROCK DEFORMATION. Final Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2002-05-24

    The Gordon Research Conference (GRC) on ROCK DEFORMATION was held at II Ciocco from 5/19/02 thru 5/24/02. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.

  5. Role of igneous rocks in the development of the gas outburst-prone nature of the black coal seams in the Mecsek area

    Energy Technology Data Exchange (ETDEWEB)

    Nemedi Varga, Z.

    1986-01-01

    In addition to the rank and structural conditions of coal seams the role of volcanic dykes is primordial from the point of view of the development of gas outburst of coal seams. The Mesco-Cenozoic volcanism of the Mecsek Mountains (South Transdanubia) is reviewed including the areal distribution of volcanics. The rock types and their frequency of occurrence are described with special emphasis to the contact metamorphism produced by the interaction of igneous and sedimentary rocks. The possibilities of gas migration as a function of the tectonic conditions are outlined exemplified by the Komlo region most famous for its gas outburst events.

  6. Low- and intermediate level radioactive waste from Risoe, Denmark. Location studies for potential disposal areas. Report no. 2. Characterization of low permeable and fractured sediments and rocks in Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Gravesen, P.; Nilsson, B.; Schack Pedersen, S.A.; Binderup, M.; Laier, T.

    2011-07-01

    The low and intermediate level radioactive waste from Risoe (the nuclear reactor buildings plus different types of material from the research periods) and radioactive waste from hospitals and research institutes have to be stored in a final disposal in Denmark for at least 300 years. In Denmark, many different kinds of fine-grained sediments and crystalline rocks occur from the ground surface down to 300 meters depth. Therefore, the possible geological situations include sediments and rocks of different composition and age. These situations are geographical distributed over large areas of Denmark. These sediments and rocks are shortly described based on existing information and include five different major types of sediments and rocks: 1: Crystalline granite and gneiss of Bornholm (because these rock types are host for waste disposals in many other countries). 2: Sandstone and shale from Bornholm (as these sediments are rela- tively homogeneous although they have fracture permeability). 3: Chalk and limestone (because these sediments may act as low permeable seals, but in most areas they act as groundwater reservoirs). 4: Fine-grained Tertiary clay deposits (as these sediments have a low permeability, are widely distributed and can reach large thicknesses). 5: Quaternary glacial, interglacial and Holocene clay deposits. These sediments are distributed all over Denmark. Following the descriptions of the geologic deposits, the areas below (including several possible locations for waste disposal sites) are selected for further investigation. The Precambrian basement rocks of Bornholm could be host rocks for the disposal. The rock types for further evaluation will be: Hammer Granite, Vang Granite, Roenne Granite, Bornholm gneiss, Paradisbakke Migmatite and Alminding Granite. In the Roskilde Fjord area around Risoe, a combination of Paleocene clays, meltwater clay and clayey till could be interesting. The area is partly included in the OSD area in North Sjaelland but

  7. 炭质岩地区公路工程地质病害特征与处治技术探讨%On Characteristics and Treatment of Geological Diseases of Highway Projects in Areas of Carbonaceous Rocks

    Institute of Scientific and Technical Information of China (English)

    黄文秀

    2013-01-01

    Through project cases, this paper analyzes and summarizes characteristics of geological diseases of highway projects in areas of carbonaceous rocks, proposing relative treatment measures for reference.%  根据工程经验,分析和总结炭质岩地区公路工程的地质病害特征,提出工程处治技术措施。

  8. 塔河地区火山岩类型、分布与主控因素%Types, distribution and main controlling factors of volcanic rocks in Tahe area

    Institute of Scientific and Technical Information of China (English)

    唐跃; 崔泽宏; 王靓靓

    2011-01-01

    通过岩心观察、地球化学方法、测井地震资料综合分析,认为塔河地区火山岩主要发育英安岩和玄武岩两大类.火山喷发主要以裂隙式喷发、侵出和溢流为主,形成塔河地区大面积火山熔岩流.火山岩的分布由西南向东北逐渐减薄,其分布主要受控于以下几个因素:①盐体覆盖区及其周缘附近,晚海西运动盐体的活动明显控制上覆火山岩岩体形态展布和分布特征,受盐体活动影响,火山岩主要残留于盐边凹陷地带和盐体覆盖区南翼,盐间凹陷火山岩厚度相对较大,盐隆地带残缺较大;②北部地区火山岩分布主要受基底喷发裂隙控制;③盐体南部斜坡地带玄武岩可能从塔里木盆地塔中地区溢流而来.%Based on core observation, geochemical exploration and a comprehensive analysis of logging and seismic data, the authors hold that that two types of volcanic rocks, I.e., dacite and basalt, occur in Tahe area of Tarim basin, that fissure eruption, extrusion and overflow made up the main forms of volcanic eruption, and that lava flow resulted in the formation of extensive volcanic rocks in Tahe area. The distribution of volcanic rocks is characterized by gradual thinning from southwest to northeast,controlled by the following factors: ①in salt body covered area and its vicinity, the activity of salt body during late Hercynian movement significandy controlled the shape and distribution of the overlying volcanic rock, as evidenced by the facts that the residual volcanic rocks are mainly found in salt-edge sags and the south wing of the area covered with salt body and that these rocks are thickest in sags between salt bodies and thinnest in the salt bulge area which experienced uplifting and erosion;② the distribution of the volcanic rocks in the north of the study area is mainly controlled by the basement fractures; ③the volcanic rocks in the southern slope area of the salt body might have been derived

  9. SHRIMP U-Pb Dating of Zircons of a Dark Eclogite and a Garnet-bearing Gneissic Granitic Rock from Bixiling, EasternDabie Area, Anhui Province: Isotope Chronological Evidence of Neoproterozoic UHP Metamorphism

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The paper reports SHRIMP U-Pb zircon data of a dark eclogite and a post-eclogite garnet-bearing gneissic granitic rock from the Bixiling area, Yuexi County, Anhui Province, in the eastern Dabie Mountains. The eclogite, which is metamorphosed basic tuff, contains very scarce zircons in omphacite or garnet, but more zircons in quartz. They usually exhibit a double-layered texture, as shown clearly in cathodoluminescence images. Their inner main parts give a206 Pb/238U age of 757±7Ma, representing the approximate age of the high-pressure (HP)-ultrahighpressure (UHP) metamorphic event duing which the eclogite was formed. The outer peripheral parts of the zircons,which have been modified by late-stage fluids, give an age of 223±3 Ma. The granitic rock contains more zircons of anatectic origin found mostly in feldspar and quartz and usually also showing a similar composite texture. The inner main parts of the anatectic zircons with oscillatory zoning give a 206Pb/238U age of 727±15Ma for the approximate age of the emplacement of the granitic rock, and their outer parts, an age of 219±3 Ma for a similar or even the same fluid event. It is thus suggested that the HP-UHP metamorphism of the Bixiling eclogite facies rocks took place during the Neoproterozoic Jinningian,and the Indosinian age values may only represent a late event in the nature of fluid activity.

  10. Impact of straw and rock-fragment mulches on soil moisture and early growth of holm oaks in a semiarid area

    Science.gov (United States)

    M. N. Jimenez; J. R. Pinto; M. A. Ripoll; A. Sanchez-Miranda; F. B. Navarro

    2017-01-01

    Planted seedlings and saplings usually exhibit low survival and growth rates under dry Mediterranean environments, especially late-successional species such as Quercus. In this work, we studied the effects of straw and rock fragment mulches on the establishment conditions of holm oak (Quercus ilex L. subsp. ballota (Def.) Samp.) in SE Spain. Soil moisture was...

  11. Research of the Rock Art from the point of view of geography: the neolithic painting of the Mediterranean area of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Cruz Berrocal, María

    2004-12-01

    Full Text Available The rock art of the Mediterranean Arch (which includes what are conventionally called Levantine Rock Art, Schematic Rock Art and Macroschematic Rock Art, among other styles, designated as part of the Human Heritage in 1997, is studied from the point of view of the Archaeology of Landscape. The information sources used were field work, cartographic analysis and analysis in GIS, besides two Rock Art Archives: the UNESCO Document and the Corpus of Levantine Cave Painting (Corpus de Pintura Rupestre Levantina. The initial hypothesis was that this rock art was involved in the process of neolithisation of the Eastern part of Iberia, of which it is a symptom and a result, and it must be understood as an element of landscape construction. If this is true, it would have a concrete distribution in the form of locational patterns. Through statistical procedures and heuristical approaches, it has been demonstrated that there is a structure of the neolithic landscape, defined by rock art, which is possible to interpret functional and economically.

    Se estudia el arte rupestre del Arco Mediterráneo (que incluye a los convencionalmente conocidos como Arte Levantino, Arte Esquemático y Arte Macroesquemático, entre otros estilos, nombrado Patrimonio de la Humanidad en 1998, desde el punto de vista de su localización. Las fuentes de información utilizadas fueron trabajo de campo, revisión cartográfica y análisis en Sistema de Información Geográfica, además de dos archivos de arte rupestre: el Expediente UNESCO y el Corpus de Pintura Rupestre Levantina. La hipótesis inicial fue que este arte rupestre se imbrica en el proceso de neolitización del Levante peninsular, del que es síntoma y resultado, y debe entenderse como un elemento de construcción paisajística, de lo que se deduce que ha de presentar una distribución determinable en forma de patrones locacionales. Por medio tanto de contrastes y descripciones estadísticas como de

  12. Geochemical Characteristics and Geological Significance of the Kafang Alkaline Volcanic Rocks in Gejiu Area, Yunnan Province%云南个旧卡房碱性火山岩地球化学特征及意义

    Institute of Scientific and Technical Information of China (English)

    张海; 方维萱; 杜玉龙

    2014-01-01

    Indosinian volcanism in the Gejiu area was divided into three phases: the Anisian Phase, the Early Ladinian Phase, and the Later Ladinian Phase-Norian Phase in the Middle Traissic Epoch. The Anisian alkali volcanic rocks were closely related to the Sn-Cu mineralization in the Kafang copper-tin deposit. The lithological and geochemical studies showed that the volcanic rocks contain 42.22% to 46.61% of SiO2, 8.61% to 18.19% of MgO, 3.52% to 7.52% of K2O+Na2O (K2O/Na2O=0.28 to 25.95) and 2.03% to 3.51% of TiO2. These volcanic rocks belong to alkalic ultrobasic volcanic rocks, and they are rich in high field-strength elements (Nb, Ta) and large-ion lithophile elements (Rb, Ba, Sr, Cs). At the same time, rare earth elements in these volcanic rocks are LREE-enriched and HREE-defected with right-inclined patterns, with obvious Eu anomalies and weak Ce negative anomalies. It may be indicated that diagenetic process of the Kafang alkali volcanic rocks might be mainly influenced by partial melting of mantle, and not obviously influenced by crustal contamination based on their geochemical features. The magmatic source area of these volcanic rocks might have derived from the partial melting of phlogopite-rich (or hornblende-rich) mantle peridotite. Moreover, the Kafang volcanic rocks share geochemical characteristics with the ocean island basalts (OIB). Based on the lithological and geochemical characteristics of the Kafang alkali volcanic rocks, these volcanic rocks might be formed in a geotectonic settings of the back-arc rift basin, and they may provide original source for the Kafang copper-tin deposit in Yunnan province, China.%个旧地区印支期的火山作用主要有三期,即中三叠世安尼期、拉丁尼克早期和拉丁尼克晚期-诺利克期。通过对与成矿关系密切的卡房铜锡矿安尼期碱性火山岩的岩相学、地球化学研究发现: SiO2含量为42.22%~46.61%, MgO含量为8.61%~18.19%, K2O+Na2O值为3.52%~7.52%, K2O/Na2O值为0

  13. Early Carboniferous adakitic rocks in the area of the Tuwu deposit, eastern Tianshan, NW China: Slab melting and implications for porphyry copper mineralization

    Science.gov (United States)

    Wang, Yin-Hong; Xue, Chun-Ji; Liu, Jia-Jun; Wang, Jian-Ping; Yang, Jun-Tao; Zhang, Fang-Fang; Zhao, Ze-Nan; Zhao, Yun-Jiang; Liu, Bin

    2015-05-01

    Existing geochronological and geochemical data for the Early Carboniferous magmatic rocks in the eastern Tianshan, Xinjiang, have been interpreted in a variety of theories regarding petrogenesis and geodynamic setting. The proposed settings include rift, back-arc basin, passive continental margin, island arc, ridge subduction, and post-collisional environment. To evaluate these possibilities, we present new SHRIMP zircon U-Pb geochronology and geochemical data, whole-rock geochemical, Hf isotope, and S isotope data for tonalitic rocks and ores associated with the Tuwu porphyry copper deposit located in the center of the late Paleozoic Dananhu-Tousuquan arc, eastern Tianshan. SHRIMP zircon U-Pb dating indicates that the magmatic activity and thus associated copper mineralization occurred ca.332 Ma. The tonalitic rocks are calc-alkaline granites with A/CNK values ranging from 1.16 to 1.58; are enriched in K, Rb, Sr, and Ba; and are markedly depleted in Nb, Ta, Ti, and Th. They show geochemical affinities similar to adakites, with high Sr, Al2O3, and Na2O contents and La/Yb ratios; low Y and Yb contents; and slight positive Eu anomalies. In situ Hf isotopic analyses of zircons yielded positive initial εHf(t) values ranging from 6.9 to 17.2. The δ34S values of the ore sulfides range from -3.0‰ to +1.7‰, reflecting a deep sulfur source. Our results indicate that the paleo-Tianshan oceanic slab was being simultaneously subducted northward beneath the Dananhu-Tousuquan arc, and southward beneath the Aqishan-Yamansu arc during the Early Carboniferous. The Tuwu adakitic tonalitic rocks were derived from the partial melting of the subducted paleo-Tianshan oceanic slab, which was subsequently hybridized by mantle wedge peridotites. The slab-derived magmas have considerably high copper contents and are highly oxidized, thus leading to porphyry copper mineralization. Such Early Carboniferous tonalitic rocks that are widespread in the eastern Tianshan define a province

  14. Microcraters on lunar rocks.

    Science.gov (United States)

    Morrison, D. A.; Mckay, D. S.; Heiken, G. H.; Moore, H. J.

    1972-01-01

    Microcrater frequency distributions have been obtained for nine Apollo rocks and an exterior chip of an Apollo 12 rock. The frequency distributions indicate that five of the Apollo 14 rocks were tumbled more than once exposing different rock faces whereas four were not tumbled and represent a single exposure interval. The cumulative frequency of craters per square centimeter was extended below optical resolution limits using a SEM scan of an exterior chip of breccia 12073. No craters with central pit diameters less than 15 microns were seen in a total area of 0.44 sq cm. A detailed SEM scan of crystal faces and glassy crater liners revealed no microcraters equal to or larger than the resolution limit of 5 microns. An upper limit of 170 craters per sq cm with central pit diameters larger than 5 microns was set. The slope of the cumulative frequency curve for craters with central pit diameters less than about 75 microns is less than that obtained by other workers.

  15. U-Th-Pb zircon geochronology on igneous rocks in the Toija and Salittu Formations, Orijärvi area, southwestern Finland: constraints on the age of volcanism and metamorphism

    Directory of Open Access Journals (Sweden)

    Christopher L. Kirkland

    2008-01-01

    Full Text Available Zircons from a felsic volcanic rock in the Toija Formation and a synvolcanic gabbro intrusion in the Salittu Formation within the Orijärvi area were dated by U-Th-Pb SIMS in order to provide depositional constraints on these formations. Zircon crystals from the felsic rock preserve a two-stage crystallisation history with zoned core domains and homogeneous rim domains. Inner domains yield a 1878±4 Ma concordia age, interpreted to determine the crystallisation of this rock. Rims yield a 1815±3 Ma concordia age interpretedto determine the regional metamorphism. Small rounded zircon grains from the Salittu gabbro, located within the Jyly shear zone, yield a concordia age of 1792±5 Ma. We interpret the grain textures to suggest that they recrystallised from inherited zircon seeds during the heat and fluid flow into the shear zone. Although no direct ages for the Salittu Formation have been recovered, field relationships imply that it was deposited between 1878−1875 Ma.

  16. Sr-Nd-Pb isotopic compositions of the lower crust beneath northern Tarim: insights from igneous rocks in the Kuluketage area, NW China

    Science.gov (United States)

    Zhang, Yan; Wei, Xun; Xu, Yi-Gang; Long, Xiao-Ping; Shi, Xue-Fa; Zhao, Jian-Xin; Feng, Yue-Xing

    2016-09-01

    The composition of lower crust of the Tarim Craton in NW China is essential to understand the petrogenesis of the ~290-275 Ma Tarim basalts and associated intermediate-felsic rocks. However, it remains poorly constrained because extremely sparse granulite terrains or granulite xenoliths have been found in the Tarim Craton. New trace element and Sr-Nd-Pb isotopic data are reported for the Neoarchean and Neoproterozoic igneous rocks widely distributed in the northern margin of the Tarim Craton. The Neoarchean granitic gneisses show fractionated REE (rare earth element) patterns [(La/Yb) N = 12-58, YbN = 10.6-36] with pronounced negative Nb-Ta and Ti anomalies. These features, together with negative ɛNdi (-0.7 to -3.2) suggest that they were derived from melting of mafic lower crust. The Neoproterozoic biotite granodiorites are strongly depleted in HREE with (La/Yb) N up to 55. They are characterized by high Sr (671-789 ppm) but very low Y (7.10-8.06 ppm) and Yb contents (0.47-0.58 ppm), showing typical features of adakitic rocks. The samples with different SiO2 contents display identical 87Sr/86Sri (0.7101-0.7103), ɛNdi (-14.1 to -15.7) and Pb isotopes (208Pb/204Pbi = 36.94-37.07). These features together with arc-like trace element patterns suggest that they were derived from melting of thickened lower crust. In comparison, the Neoproterozoic hornblende-biotite granodiorites have similar trace element compositions except for weaker depletion in HREE and have lower 87Sr/86Sri (0.7078) and initial Pb isotopes, and higher ɛNdi (-12.3 to -12.7). This suggests that they were formed by melting of old lower continental crust at a shallower depth than the biotite granodiorites. These rocks were derived from the lower crust, thus providing valuable information on the nature of the lower crust beneath northern Tarim. Combined with published data, the 87Sr/86Sri, ɛNdi, 206Pb/204Pbi and ɛHfi of the northern Tarim lower crust ranges from 0.7055 to 0.7103, from -12 to -17

  17. U-Pb zircon geochronology of Mesoproterozoic postorogenic rocks and implications for post-Ottawan magmatism and metallogenesis, New Jersey Highlands and contiguous areas, USA

    Science.gov (United States)

    Volkert, R.A.; Zartman, R.E.; Moore, P.B.

    2005-01-01

    Postorogenic rocks are widespread in Grenville terranes of the north-central Appalachians where they form small, discordant, largely pegmatitic felsic intrusive bodies, veins, and dikes, and also metasomatic calcic skarns that are unfoliated and postdate the regional 1090 to 1030 Ma upper amphibolite- to granulite-facies metamorphism related to the Grenville (Ottawan) Orogeny. Zircons from magmatic and nonmagmatic rocks from northern New Jersey and southern New York were dated to provide information on the regional tectonomagmatic and metallogenic history following Ottawan orogenesis. We obtained U-Th-Pb zircon ages of 1004 ?? 3 Ma for pegmatite associated with the 1020 ?? 4 Ma Mount Eve Granite near Big Island, New York, 986 ?? 4 Ma for unfoliated, discordant pegmatite that intrudes supracrustal marble at the Buckwheat open cut, Franklin, New Jersey, ???990 Ma for a silicate-borate skarn layer in the Franklin Marble at Rudeville, New Jersey, and 940 ?? 2 Ma for a calc-silicate skarn layer at Lower Twin Lake, New York. This new data, together with previously published ages of 1020 ?? 4 to 965 ?? 10 Ma for postorogenic rocks from New Jersey and southern New York, provide evidence of magmatic activity that lasted for up to 60 Ma past the peak of high-grade metamorphism. Postorogenic magmatism was almost exclusively felsic and involved relatively small volumes of metaluminous to mildly peraluminous melt that fractionated from an A-type granite parent source. Field relationships suggest the melts were emplaced along lithosphere-scale fault zones in the Highlands that were undergoing extension and that emplacement followed orogenic collapse by least 30 Ma. Postorogenic felsic intrusions correspond to the niobium-yttrium-fluorine (NYF) class of pegmatites of C??erny?? (1992a). Geochronologic data provide a temporal constraint on late-stage hydrothermal activity and a metallogenic event in New Jersey at ???990 to 940 Ma that mineralized pegmatites with subeconomic to

  18. 27 CFR 9.203 - Saddle Rock-Malibu.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Saddle Rock-Malibu. 9.203... Saddle Rock-Malibu. (a) Name. The name of the viticultural area described in this section is “Saddle Rock-Malibu”. For purposes of part 4 of this chapter, “Saddle Rock-Malibu” is a term of...

  19. 40Ar-39Ar dating and geologi-cal implication of auriferous altered rocks from the middle-deep section of Q875 gold-quartz vein in Xiaoqinling area, Henan, China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The 40Ar-39Ar age method is employed in this work to analyze the aurif erous altered rocks from the middle-deep section of the Q875 gold-quartz vein in the Xiaoqinling area, and the results show that the main gold deposition of the Q875 occurred in ca. 128-126 Ma. As a typical gold-bearing quartz vein in this gold-rich area, the age data obtained from the Q875 also constrain on the metal logenic time of the lode gold deposits developed in the same geological settings . This geochronological study supplies new evidence for further understanding the timing of gold mineralization, the genesis of gold deposits and the geodynamic settings in Xiaoqinling area.

  20. Textural and structural features, composition and formation conditions of arenaceous rocks in PK1 horizon, Pokursk suite in south-eastern Pur-Tazovsk area (Yamalo-Nenets Autonomous Territory)

    Science.gov (United States)

    Nedolivko, N.; Perevertailo, T.; Barkalova, A.; Dolgaya, T.

    2015-02-01

    Terrigenous deposits of the productive PK1 horizon in Pokursk suite of Pur-Tazovsk area (Yamalo-Nenets Autonomous Territory) were studied to specify the structure and identify the formation features. Complex horizon structure of sequential silt, mudrock interbedding and alternation has been identified. Littoral-marine type of sedimentation (occurring during the total marine transgression increase) by the help of genetic rock features identified during the core sampling and by the granulometry and X-ray-phase results analysis has been determined.

  1. Potential areas of ground-water discharge in the Basin and Range carbonate-rock aquifer system, White Pine County, Nevada, and adjacent parts of Nevada and Utah

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data represent potential areas of ground-water discharge for selected hydrographic areas in eastern Nevada and western Utah. The data are based on phreatophyte...

  2. Source rock potential in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Raza, H.A. (Hydrocarbon Development Institute of Pakistan, Islamabad (Pakistan))

    1991-03-01

    Pakistan contains two sedimentary basins: Indus in the east and Balochistan in the west. The Indus basin has received sediments from precambrian until Recent, albeit with breaks. It has been producing hydrocarbons since 1914 from three main producing regions, namely, the Potwar, Sulaisman, and Kirthar. In the Potwar, oil has been discovered in Cambrian, Permian, Jurassic, and Tertiary rocks. Potential source rocks are identified in Infra-Cambrian, Permian, Paleocene, and Eocene successions, but Paleocene/Eocene Patala Formation seems to be the main source of most of the oil. In the Sulaiman, gas has been found in Cretaceous and Tertiary; condensate in Cretaceous rocks. Potential source rocks are indicated in Cretaceous, Paleocene, and Eocene successions. The Sembar Formation of Early Cretaceous age appears to be the source of gas. In the Kirthar, oil and gas have been discovered in Cretaceous and gas has been discovered in paleocene and Eocene rocks. Potential source rocks are identified in Kirthar and Ghazij formations of Eocene age in the western part. However, in the easter oil- and gas-producing Badin platform area, Union Texas has recognized the Sembar Formation of Early Cretaceous age as the only source of Cretaceous oil and gas. The Balochistan basin is part of an Early Tertiary arc-trench system. The basin is inadequately explored, and there is no oil or gas discovery so far. However, potential source rocks have been identified in Eocene, Oligocene, Miocene, and Pliocene successions based on geochemical analysis of surface samples. Mud volcanoes are present.

  3. 修水碳硅泥岩型铀矿特征及资源潜力分析%Characteristics and Resource Potential of Arbonaceous-siliceous-argillitic Rock-hosted Uranium Deposits in Xiushui Area

    Institute of Scientific and Technical Information of China (English)

    胡茂梅; 杨松; 邵飞; 刘守坚; 梁发辉; 邓军

    2012-01-01

    修水碳硅泥岩型铀矿主要有保峰源、董坑、大椿、白土、洞下矿床,矿床集中分布于修水复向斜中,构成修水矿化集中区,该矿化集中区位于修水-宁国-开化碳硅泥岩成矿带西端,是我国重要的碳硅泥岩型铀矿主产地,具有优越的区域铀成矿地质条件.通过铀矿调查评价工作,分析厘定了研究区岩性岩相、构造、岩相古地理、铀源等条件,明确了灯影组、王音铺组碳硅泥岩建造为研究区主要铀源层、赋矿层,新发现了观音堂组中的工业铀矿体.以铀成矿地质条件、铀矿化特征分析为重点,预测铀资源潜力.%The arbonaceous-siliceous-argillitic rock-hosted uranium deposits mainly include Baofengyuan, Dongkeng,Dachun, Daitu,Dongxia in Xiushui area,which are concentrated in Xiushui synclinorium, and formed into mineralization concentration area which is located in western of the Xiushui - Ningguo - Kaihua carbonaceous-siliceous-argillitic rock in metallogenic- belt, it is the main origin of carbonaceous-siliceous-argillitic rock type u-ranium deposits in our country, we have carried out by the uranium survey and evaluation work, an analysis on the area of lithology and facies, structure, lithofacies palaeogeography, uranium source conditions, clearled the Dengying Formation, Wang Yin Pu group of carbonaceous-siliceous-argillitic rock construction for regional uranium source, host strata, found a new industrial uranium ore body in Buddism godness Guanyin hall group.This page is based on the geological conditions of uranium metallogenesis, uranium mineralization characteristics analysis to predict the potential of uranium resources.

  4. ONKALO rock mechanics model (RMM). Version 2.3

    Energy Technology Data Exchange (ETDEWEB)

    Haekkinen, T.; Merjama, S.; Moenkkoenen, H. [WSP Finland, Helsinki (Finland)

    2014-07-15

    The Rock Mechanics Model of the ONKALO rock volume includes the most important rock mechanics features and parameters at the Olkiluoto site. The main objective of the model is to be a tool to predict rock properties, rock quality and hence provide an estimate for the rock stability of the potential repository at Olkiluoto. The model includes a database of rock mechanics raw data and a block model in which the rock mechanics parameters are estimated through block volumes based on spatial rock mechanics raw data. In this version 2.3, special emphasis was placed on refining the estimation of the block model. The model was divided into rock mechanics domains which were used as constraints during the block model estimation. During the modelling process, a display profile and toolbar were developed for the GEOVIA Surpac software to improve visualisation and access to the rock mechanics data for the Olkiluoto area. (orig.)

  5. CERN Rocks

    CERN Document Server

    2004-01-01

    The 15th CERN Hardronic Festival took place on 17 July on the terrace of Rest 3 (Prévessin). Over 1000 people, from CERN and other International Organizations, came to enjoy the warm summer night, and to watch the best of the World's High Energy music. Jazz, rock, pop, country, metal, blues, funk and punk blasted out from 9 bands from the CERN Musiclub and Jazz club, alternating on two stages in a non-stop show.  The night reached its hottest point when The Canettes Blues Band got everybody dancing to sixties R&B tunes (pictured). Meanwhile, the bars and food vans were working at full capacity, under the expert management of the CERN Softball club, who were at the same time running a Softball tournament in the adjacent "Higgs Field". The Hardronic Festival is the main yearly CERN music event, and it is organized with the support of the Staff Association and the CERN Administration.

  6. Geochemistry and Tectonic Setting of Late Triassic Volcanic Rocks in Reshui Area,Qinghai%青海热水地区晚三叠世火山岩地球化学特征及构造环境

    Institute of Scientific and Technical Information of China (English)

    李运冬; 刘小玉

    2014-01-01

    青海热水地区位于秦祁昆三大造山带的结合部位,该区发育晚三叠世鄂拉山组火山岩。岩石类型以英安岩及英安质火山碎屑岩为主,其次为中性的安山质火山岩和酸性的流纹质火山岩,为一套高 K、低 Ti、准铝质的钙碱性系列火山岩。SiO2含量为59.62%~76.46%,总碱含量 ALK 为6.59%~8.04%,ANK 在1.14~1.80,里特曼系数σ在1.72~2.41,岩石矿物结晶分离程度高,但固结程度一般。稀土总量 REE在126.76×10-6~240.07×10-6,LREE/HREE均值为10.19,属轻稀土富集型,且轻稀土富集程度高于重稀土富集程度,δEu 值多在0.37~0.56亏损较为明显,稀土元素标准化配分曲线均呈右倾较缓的平滑曲线。大离子半径亲石元素 Rb、Ba、U、K、Th较为富集,高场强元素 Nb、Ta、Ti、P等较为亏损,原始地幔标准化配分曲线呈明显左高右低的“W”型,具有明显的弧火山岩特点。Mg#大部分在16~36,206 Pb/204 Pb=18.181~18.218,207 Pb/204 Pb=15.570~15.588,208 Pb/204 Pb=38.368~38.529,显示岩浆来源于下地壳。该区火山岩与 A型俯冲构造活动有关,利用 Hf/3-Th-Nb/16等构造环境判别图解分析,其形成于陆缘弧环境。%Reshui area is located in the binding site of Qinling,Qilianshan and Kunlunshan orogenic belt, and the late Triassic volcanic rock developed in the area is part of Elashan formation.As a set of volcano rocks with high K content,low Ti content and metaluminous calc-alkaline characteristics,the late Triassic rock are mainly consisted of dacite and dacitic pyroclastic rock,followed by neutral andesitic volcano rock and acidic rhyolitic volcano rock.The content of SiO2 is between 59.62% and 76.46%,the content of ALK ranges from 6.59% to 8.04%,the content of ANK is from 1.14 to 1.80,and the value of Rittmann coefficient varies between 1.72 and 2.41,the degree of rock mineral fractionation crystallization is high,but the degree of consolidation is common.The total of REE is between 126.76

  7. Active microwave remote sensing research program plan. Recommendations of the Earth Resources Synthetic Aperture Radar Task Force. [application areas: vegetation canopies, surface water, surface morphology, rocks and soils, and man-made structures

    Science.gov (United States)

    1980-01-01

    A research program plan developed by the Office of Space and Terrestrial Applications to provide guidelines for a concentrated effort to improve the understanding of the measurement capabilities of active microwave imaging sensors, and to define the role of such sensors in future Earth observations programs is outlined. The focus of the planned activities is on renewable and non-renewable resources. Five general application areas are addressed: (1) vegetation canopies, (2) surface water, (3) surface morphology, (4) rocks and soils, and (5) man-made structures. Research tasks are described which, when accomplished, will clearly establish the measurement capabilities in each area, and provide the theoretical and empirical results needed to specify and justify satellite systems using imaging radar sensors for global observations.

  8. Study on Water-Rock Interaction of Debris Flow in Taihang Mountain Area of Hebei Province%河北太行山区泥石流启动的水岩相互作用

    Institute of Scientific and Technical Information of China (English)

    王滨; 董昕; 王维早; 齐剑锋

    2012-01-01

    Debris flow, as a geological disaster, is a mixture of solid and liquid and water-rock interaction occurs during the formation process. Based on the analysis of several factors initiating debris flow in the Taihang mountain area,including the topography, precipitation, material source, and human activities, two types of debris flow initiating mechanisms are determined: the rock fall-landslide and flood. From the aspect of the water-rock coupling system,the chemical,physical,and mechanical interactions between the flood and solid particles during the formation of debris flow in the Taihang mountain area are investigated. Moreover, this paper illustrates the promotion mechanism of water-rock interaction on initiating debris flow, which can provide theoretical support for establishing a forecast model of debris flow.%泥石流作为一种固—液混合而形成的地质灾害,其启动过程中必然存在着水与岩土体之间的相互作用.根据对太行山区泥石流形成的地形地貌、降雨、物源和人类活动特征等影响因素的分析,确定太行山区泥石流的崩滑动力和洪水动力两种启动类型.在此基础上,从水—岩系统耦合作用的角度,研究了太行山区泥石流形成过程中,洪水与固体颗粒之间彼此促进、相互制约的水岩化学作用、水岩物理作用和水岩力学作用,阐明了水岩相互作用对泥石流初始形成的促进机制,从而为泥石流启动预测预报体系的建立提供理论支撑.

  9. Huashan rock paintings and other simitar paintings

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    China is one of the countries with the rechest rock paintings in the world. The Huashan rock paintings features color paintings, quite different from those in the North China areas where petroglyphs were created by engraving, chiseling,incising,or grinding,such as those in Inner Mongolia and Helan Mountains in Gansu.The rock paintings at Ulanchabu of Inner Mongolia are regarded as works of the Neolithic age,bronze age and iron age ,featuring mainly such grassland animals as

  10. Melt-rock interactions and fabric development of peridotites from North Pond in the Kane area, Mid-Atlantic Ridge: Implications of microstructural and petrological analyses of peridotite samples from IODP Hole U1382A

    Science.gov (United States)

    Harigane, Yumiko; Abe, Natsue; Michibayashi, Katsuyoshi; Kimura, Jun-Ichi; Chang, Qing

    2016-06-01

    North Pond is an isolated sedimentary pond on the western flank of the Kane area along the Mid-Atlantic Ridge. Drill-hole U1382A of IODP Expedition 336 recovered peridotite and gabbro samples from a sedimentary breccia layer in the pond, from which we collected six fresh peridotite samples. The peridotite samples came from the southern slope of the North Pond where an oceanic core complex is currently exposed. The samples were classified as spinel harzburgite, plagioclase-bearing harzburgite, and a vein-bearing peridotite that contains tiny gabbroic veins. No obvious macroscopic shear deformation related to the formation of a detachment fault was observed. The spinel harzburgite with a protogranular texture was classified as refractory peridotite. The degree of partial melting of the spinel harzburgite is estimated to be ˜17%, and melt depletion would have occurred at high temperatures in the uppermost mantle beneath the spreading axis. The progressive melt-rock interactions between the depleted spinel harzburgite and the percolating melts of Normal-Mid Ocean Ridge Basalt (N-MORB) produced the plagioclase-bearing harzburgite and the vein-bearing peridotite at relatively low temperatures. This implies that the subsequent refertilization occurred in an extinct spreading segment of the North Pond after spreading at the axis. Olivine fabrics in the spinel and plagioclase-bearing harzburgites are of types AG, A, and D, suggesting the remnants of a mantle flow regime beneath the spreading axis. The initial olivine fabrics appear to have been preserved despite the later melt-rock interactions. The peridotite samples noted above preserve evidence of mantle flow and melt-rock interactions beneath a spreading ridge that formed at ˜8 Ma.

  11. Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Fowey Rocks Lighthouse, 2006 - 2009 (NODC Accession 0093025)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

  12. Institute for Rock Magnetism established

    Science.gov (United States)

    Banerjee, Subir K.

    There is a new focal point for cooperative research in advanced rock magnetism. The University of Minnesota in Minneapolis has established an Institute for Rock Magnetism (IRM) that will provide free access to modern equipment and encourage visiting fellows to focus on important topics in rock magnetism and related interdisciplinary research. Funding for the first three years has been secured from the National Science Foundation, the W.M. Keck Foundation, and the University of Minnesota.In the fall of 1986, the Geomagnetism and Paleomagnetism (GP) section of the AGU held a workshop at Asilomar, Calif., to pinpoint important and emerging research areas in paleomagnetism and rock magnetism, and the means by which to achieve them. In a report of this workshop published by the AGU in September 1987, two urgent needs were set forth. The first was for interdisciplinary research involving rock magnetism, and mineralogy, petrology, sedimentology, and the like. The second need was to ease the access of rock magnetists and paleomagnetists around the country to the latest equipment in modern magnetics technology, such as magneto-optics or electronoptics. Three years after the publication of the report, we announced the opening of these facilities at the GP section of the AGU Fall 1990 Meeting. A classified advertisement inviting applications for visiting fellowships was published in the January 22, 1991, issue of Eos.

  13. Rollerjaw Rock Crusher

    Science.gov (United States)

    Peters, Gregory; Brown, Kyle; Fuerstenau, Stephen

    2009-01-01

    The rollerjaw rock crusher melds the concepts of jaw crushing and roll crushing long employed in the mining and rock-crushing industries. Rollerjaw rock crushers have been proposed for inclusion in geological exploration missions on Mars, where they would be used to pulverize rock samples into powders in the tens of micrometer particle size range required for analysis by scientific instruments.

  14. Geophysical prospecting method in intrusive rocks area fight a drought to find water wells set%物探方法在侵入岩地区抗旱找水定井中的应用

    Institute of Scientific and Technical Information of China (English)

    宋希利; 宋鹏; 田明阳; 彭玉明

    2012-01-01

    Intrusive rocks in the area of groundwater is difficult to find, but more abundant in the dry season the groundwater more difficult to find, to quickly resolve severe drought disaster in Shandong Yimcngshan people much-needed human and livestock water consumption through advanced and effective geophysical methods and reasonable working arrangement greatly increased drought in the intrusive rocks in the area to find water wells set the speed and rate guarantees as well, by the construction of drilling results verify the geophysical inference realistic, given the success rate of 96% well, single-well water yield are far beyond the estimated amount of water, to find a more extensive local groundwater resources, water resources needed to solve the problem of the masses, the people and the old liberated areas have been highly appreciated by the local government. Proved Yimengshan intrusive rocks in the area of geophysical methods based on different characteristics and be well area is difficult, easy, and CSAMT method were selected degree of resistivity sounding method to find underground water source not only improves the speed and success rate of well set, but also made good hydrogeological effects, it is in similar application areas. Practical work in the specific practice, one can not determine the geological survey of the ground target range and set well drilling difficult areas, the use of controlled source audio magnetotelluric: method is fast and efficient features, to sweep the work surface, suggesting that rock construction of fracture zone, delineated area that is rock crushing low resistance, water lots, and to determine the depth of drilling wells; the second is on the ground within the geological survey to determine, using the resistivity sounding method, the use of a single curve reflects the broken rocks, water section to determine the visual characteristics of the aquifer and depth.%侵入岩地区寻找地下水难度大,而在干旱季节找出较为

  15. Cenozoic volcanic rocks of Saudi Arabia

    Science.gov (United States)

    Coleman, R.G.; Gregory, R.T.; Brown, G.F.

    2016-01-01

    The Cenozoic volcanic rocks of Saudi Arabia cover about 90,000 km2, one of the largest areas of alkali olivine basalt in the world. These volcanic rocks are in 13 separate fields near the eastern coast of the Red Sea and in the western Arabian Peninsula highlands from Syria southward to the Yemen Arab Republic.

  16. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正>20041935 Chen Bailin (China University of Geosciences, Beijing);Shu Bin X-Ray Analysis of Deformed Rocks from Beishan Area, Gansu Province, China (Journal of Jilin University (Earth Science Edition ), ISSN 1671-5888 CN22-1343/P, 33(4), 2003, p. 424-429, 442, 2 illus. , 3 tables, 13 refs. )

  17. Detrital mode and whole-rock geochemistry of the fluvial succession, Pishin Belt, Pakistan: Implications on provenance and source area weathering in periferal foreland basins

    DEFF Research Database (Denmark)

    Kasi, Aimal Khan; Kassi, Akhtar Muhammad; Friis, Henrik;

    2016-01-01

    derived from Muslim Bagh-Zhob Ophiolite. Malthanai Formation has higher CIA and CIW values (68.96 and 77.53) than Dasht Murgha Group (63.87 & 70.93); however, they both indicate low to moderate weathering intensities. Dasht Murgha group and Malthanai Formation have higher weathering of the source area...

  18. Constraints for estimating the future burial depth of host rocks for geological waste disposal: a case study from the Boom Clay, Campine area, Northern Belgium

    Science.gov (United States)

    Beerten, K.; De Craen, M.; Brassinnes, S.

    2012-04-01

    An important requirement for geological formations hosting a repository for radioactive waste is sufficient depth to ensure isolation of the waste for a very long time period, up to 1 Ma and beyond. Over such long timescales, the repository depth and the thickness of the overburden may vary significantly due to various geodynamic processes. In Belgium, the Boom Clay in the Campine area (NE-Belgium) is considered as reference host formation for the geological disposal of radioactive waste. First results are presented that illustrate the possible impact of future climate change (based on several scenarios studied in the BIOCLIM project (BIOCLIM, 2001)) and tectonic movements in the Campine area on the thickness of the sediment mass overlying the Boom Clay. At present, the subcrop area of Boom Clay in the Campine area is relatively flat (between ~ 0 m a.s.l. near the river Scheldt estuary in the west and ~ 60 m a.s.l. on the Campine Plateau in the east) and is occupied by several sub-basins that belong to the rivers Meuse and Scheldt. Future development of the area will heavily depend on the behaviour of these rivers and tributaries throughout the considered timeframe, in response to climatic changes and tectonic movements. The area is characterised by a long burial history, with some minor isolated uplift and erosional events during the last 30 Ma. In a global warming scenario during a long interglacial (> 50 ka AP), and/or in the case of subsidence, (relative) sea-level may rise such that various parts of the Boom Clay area will be occupied by the marine realm. This is likely to be a minimal erosion scenario because the baseline for landscape evolution will rise in the upstream parts while estuarine and marine deposition may increase the thickness of the overburden in the downstream parts. In the case of a continuation of Pleistocene glacial cycles, i.e. the alternation between warm interglacials and cold glacials, the area will be exposed to erosion and denudation

  19. Thermally induced rock stress increment and rock reinforcement response

    Energy Technology Data Exchange (ETDEWEB)

    Hakala, M. [KMS Hakala Oy, Nokia (Finland); Stroem, J.; Nujiten, G.; Uotinen, L. [Rockplan, Helsinki (Finland); Siren, T.; Suikkanen, J.

    2014-07-15

    This report describes a detailed study of the effect of thermal heating by the spent nuclear fuel containers on the in situ rock stress, any potential rock failure, and associated rock reinforcement strategies for the Olkiluoto underground repository. The modelling approach and input data are presented together repository layout diagrams. The numerical codes used to establish the effects of heating on the in situ stress field are outlined, together with the rock mass parameters, in situ stress values, radiogenic temperatures and reinforcement structures. This is followed by a study of the temperature and stress evolution during the repository's operational period and the effect of the heating on the reinforcement structures. It is found that, during excavation, the maximum principal stress is concentrated at the transition areas where the profile changes and that, due to the heating from the deposition of spent nuclear fuel, the maximum principal stress rises significantly in the tunnel arch area of NW/SW oriented central tunnels. However, it is predicted that the rock's crack damage (CD, short term strength) value of 99 MPa will not be exceeded anywhere within the model. Loads onto the reinforcement structures will come from damaged and loosened rock which is assumed in the modelling as a free rock wedge - but this is very much a worst case scenario because there is no guarantee that rock cracking would form a free rock block. The structural capacity of the reinforcement structures is described and it is predicted that the current quantity of the rock reinforcement is strong enough to provide a stable tunnel opening during the peak of the long term stress state, with damage predicted on the sprayed concrete liner. However, the long term stability and safety can be improved through the implementation of the principles of the Observational Method. The effect of ventilation is also considered and an additional study of the radiogenic heating effect on the

  20. Delineation of Landslide Prone Areas based on Geotechnical and Mineralogical Evaluation of Rocks and Soil to Understand the Failure Zones in a part of Alaknanda Valley, Garhwal Himalaya, India

    Science.gov (United States)

    Asthana, H.; Singh, N.; Sen, R.; Vishwakarma, C. A.; Singh, P.; Rena, V.; Mukherjee, S.

    2016-12-01

    The exclusive physiographic, tectonic and climatic conditions, along with natural and anthropogenic factors make the Himalayan terrain prone to land failure. The land which can be used for the developmental activities are severely limited. Increasing population density, societal requirements has put stress on the same quantum of land and created considerable anthropogenic problems in landscape equilibrium. In present study thematic maps have been developed for the Alaknanda valley in the Garhwal Himalaya of Uttrakhand to assess the potential landslide hazard zones. This has been done using remote sensing GIS data, topographic maps and field investigations. Based on above results landslide hazard zonation has been done to determine the spatio-temporal extent of landslide occurrence and vulnerability. Outlook of the slopes and identification of the discontinuities present in the terrain was done on the basis of representative samples through field investigations. Grain size analysis of the following samples was carried out to estimate the percentage sand, silt and clay content of the soil. Based on the proportions of different particle sizes, a soil textural category may be assigned to the samples. Results indicated that the landslides along the section of Devprayag-Badrinath National Highway are mainly debris slides, debris flows, rock slides and rock falls. Following landslide masses are chiefly composed of boulders, rock fragments and soil. Debris flows are mostly restrained along lines of natural drainage. The area is under severe anthropogenic as well as natural influence which can be further responsible for increase in the shear stress beyond the threshold level, thus decreasing the slope stability resulting in failure zones. A high resolution remotely sensed data in digital form has been proved to be an essential tool for the preparation, interpretation and analysis of the data obtained in the GIS environment. Further mineralogical evaluations are done to

  1. Meteorite Linked to Rock at Meridiani

    Science.gov (United States)

    2004-01-01

    This meteorite, a basalt lava rock nearly indistinguishable from many Earth rocks, provided the first strong proof that meteorites could come from Mars. Originally weighing nearly 8 kilograms (17.6 pounds), it was collected in 1979 in the Elephant Moraine area of Antarctica. The side of the cube at the lower left in this image measures 1 centimeter (0.4 inches). This picture shows a sawn face of this fine-grained gray rock. (The vertical stripes are saw marks.) The black patches in the rock are melted rock, or glass, formed when a large meteorite hit Mars near the rock. The meteorite impact probably threw this rock, dubbed 'EETA79001,' off Mars and toward Antarctica on Earth. The black glass contains traces of martian atmosphere gases. The Mars Exploration Rover Opportunity has discovered that a rock dubbed 'Bounce' at Meridiani Planum has a very similar mineral composition to this meteorite and likely shares common origins. Bounce itself is thought to have originated outside the area surrounding Opportunity's landing site; an impact or collision likely threw the rock away from its primary home.

  2. Influence of Geological and Geomorphological Characteristics on Groundwater Occurrence in Deccan Basalt Hard Rock Area of Tawarja river Sub-Basin Latur, Maharashtra, India

    Directory of Open Access Journals (Sweden)

    Babar

    2012-04-01

    Full Text Available The entire study area is covered by Deccan basalt formations comprising nearly horizontal lava flows of late Cretaceous to early Eocene. There are eight flows of lava found in the area and these flows have been considered to be a result of fissure type lava eruption. The types of basaltic flows occurring in the area are simple basalt (aa type and vesicular-amygdaloidal (Compound pahoehoe type basalt flow and also red bole beds (Tachylitic bands are observed in the exposures, quarries and well sections. The drainage pattern varies from dendritic to sub-dendritic and sub-parallel. The bifurcation ratio is moderate (3.00 to 4.67 and the lower values of drainage density (1.77 km/km2 and stream frequency (1.74 streams/km2 indicates the region is of permeable subsoil strata of the basin. Morphometric attributes like form factor (0.85, circularity ratio (0.37 and elongation ratio (0.63 reflects the early mature stage of erosional development. The groundwater occurrence with reference to hydrogeological and geomorphological characters of the sub-basin is discussed. The groundwater occurrence is good productive in the geomorphic surfaces like moderately dissected plateau and pediplains, moderate in highly dissected plateau and lateritic uplands and poor in denudational hills.

  3. 文登地区浅部干热岩地热资源的赋存条件分析%Analysis on Occurrence Conditions of Geothermal Resources in Shallow Hot Dry Rock in Wendeng Area

    Institute of Scientific and Technical Information of China (English)

    田立强; 范士彦

    2016-01-01

    Five natural hot springs in Wendeng area distributed on the edge of the Hetao with enough water, high water quality and high water temperature. It is considered that there are multiple abnormal geothermal gradient in the region. The geothermal gradient anomaly has close relation with the subduction of the Pacific plate edge belt, Sulu UHP metamorphic belt heat of radioactive elements of abnormal and deep fracture zone thermal interaction. According to the analysis on thermal conductivity of various lithology, it is regarded that quartzite granite, granitic gneiss and gneiss are favorable optimal objective layers for development and utilization of hot dry rock resources. It is suggesed that in five natural hot springs in the area, by using geophysical prospecting, drilling and other explora⁃tion means, the deep fracture zone has been found out, geothermal gradient anomaly area has been surveyed, and shallow geothermal resources of hot dry rock storage area has been looked for.%文登地区的5处天然温泉,多分布于河套边沿,水源足,水质优,水温高,证明该地区存在多处地温梯度异常。分析认为该地温梯度异常与太平洋板块边沿俯冲带、苏鲁超高压变质带放射性元素生热异常、深大断裂带的导热作用有关。根据各种岩性的导热性分析,认为含石英岩脉的花岗岩、花岗片麻岩或片麻岩为有利于干热岩资源开发利用的最优目的层。建议在5处天然温泉区域内,利用物探、钻探等勘查手段相结合,查明深大断裂带,调查地温梯度异常区,寻找浅部干热岩地热资源赋存区。

  4. Hot dry rock geothermal energy

    Science.gov (United States)

    Heiken, G.; Murphy, H.; Nunz, G.; Potter, R.

    1981-08-01

    Man-made geothermal systems are discussed which make it possible to extract heat from hot rocks in areas where natural fluids are insufficient for the development of hydrothermal energy. The location and magnitude of high- and low-temperature geothermal resources in the USA for such hot dry rock (HDR) systems are examined. An HDR concept is described in which water is injected into one of two nearly parallel wells connected at depth by man-made fractures; the injected water circulates through the fracture system, where it is heated by conduction from the hot rock, and hot fluid, which can be used for heating or for electric power generation, rises through the second well. Some heat-extraction experiments using the described concept are reviewed which are being conducted in a complex volcanic field in New Mexico. The economics of HDR energy is evaluated.

  5. Geotechnical Descriptions of Rock and Rock Masses.

    Science.gov (United States)

    1985-04-01

    weathering is presented by Dornbusch (1982). 39. Mechanical, or physical, weathering of rock occurs primarily by (a) freeze expansion (or frost wedging...34Engineering Classifica- tion of In-Situ Rock," Technical Report No. AFWL-TR-67-144, Air Force Weapons Laboratory, Kirtland Air Force Base, N. Mex. Dornbusch , W

  6. Analytical results and sample locality map for rock, stream-sediment, and soil samples, Northern and Eastern Coloado Desert BLM Resource Area, Imperial, Riverside, and San Bernardino Counties, California

    Science.gov (United States)

    King, Harley D.; Chaffee, Maurice A.

    2000-01-01

    INTRODUCTION In 1996-1998 the U.S. Geological Survey (USGS) conducted a geochemical study of the Bureau of Land Management's (BLM) 5.5 million-acre Northern and Eastern Colorado Desert Resource Area (usually referred to as the NECD in this report), Imperial, Riverside, and San Bernardino Counties, southeastern California (figure 1). This study was done in support of the BLM's Coordinated Management Plan for the area. This report presents analytical data from this study. To provide comprehensive coverage of the NECD, we compiled and examined all available geochemical data, in digital form, from previous studies in the area, and made sample-site plots to aid in determining where sample-site coverage and analyses were sufficient, which samples should be re-analyzed, and where additional sampling was needed. Previous investigations conducted in parts of the current study area included the National Uranium Resource Evaluation (NURE) program studies of the Needles and Salton Sea 1? x 2? quadrangles; USGS studies of 12 BLM Wilderness Study Areas (WSAs) (Big Maria Mountains, Chemehuevi Mountains, Chuckwalla Mountains, Coxcomb Mountains, Mecca Hills, Orocopia Mountains, Palen-McCoy, Picacho Peak, Riverside Mountains, Sheephole Valley (also known as Sheep Hole/Cadiz), Turtle Mountains, and Whipple Mountains); and USGS studies in the Needles and El Centro 1? x 2? quadrangles done during the early 1990s as part of a project to identify the regional geochemistry of southern California. Areas where we did new sampling of rocks and stream sediments are mainly in the Chocolate Mountain Aerial Gunnery Range and in Joshua Tree National Park, which extends into the west-central part of the NECD, as shown in figure 1 and figure 2. This report contains analytical data for 132 rock samples and 1,245 stream-sediment samples collected by the USGS, and 362 stream-sediment samples and 189 soil samples collected during the NURE program. All samples are from the Northern and Eastern Colorado

  7. Petrography and whole-rock geochemistry of Oligocene-Miocene Khojak Formation Khojak-Pishin Belt, Pakistan: Implications on provenance and source-area weathering

    DEFF Research Database (Denmark)

    Kakar, Din Muhammad; Kasi, Aimal K.; Kassi, Aktar Muhammad

    2016-01-01

    . The higher SiO2/Al2O3 ratios (4.0) show moderately mature nature of the sandstone. The weathering indices such as Chemical Index of Alteration (CIA; 76.69), Chemical Index of Weathering (CIW; 86.79), Chemical Proxy of Alteration (CPA; 92.33) and Index of Chemical Variability (ICV; 16.83) suggest moderate...... to intense weathering of the source terrain. The high Th/U values (5.25) as compared to Upper Continental Crust (UCC; 3.82) also support the enhanced weathering of the source area. Trace elements such as Zr, Nb, Y, Th and U are slightly enriched compared to UCC suggest the dominantly felsic sources...... by distant Kohistan Island Arc and en-route Waziristan, Zhob and Muslim Bagh Ophiolite and associated Mélages. The sediment dispersal towards south-southwest was controlled by Chaman-Nushki transform fault system....

  8. From stones to rocks

    Science.gov (United States)

    Mortier, Marie-Astrid; Jean-Leroux, Kathleen; Cirio, Raymond

    2013-04-01

    requirements of educational authorities, the reflection of the president and vice president of the association and some other high school teachers will help with the evolution and progression of Wegener's theory. I will present to you how the examination of clues found in different areas of the Alps will be taken by the students to reconstitute the evolution of research begun by Wegener in the early 1900s for the understanding of the oceanic expansion. Moreover this experience reinforces the scientific mindset of the class, as well as, what they see originally as an ordinary rock will become a precious rock of scientific significance.

  9. 中国东部岩盐矿区建造盐穴储气库地质条件分析%GEOLOGICAL CONDITION ANALYSIS ON GAS STORAGE FOR BUILDING SALT CAVERN OF ROCK SALT AREA IN EASTERN CHINA

    Institute of Scientific and Technical Information of China (English)

    王少华; 杨树杰

    2015-01-01

    The halite bed of eastern China is frequentlyinterbedded with the other rocks. According to the different rock salt bed interlayer of salt bearing zone, the section structure is separated into three types including the first interlayer which is easy to build salt cavern and dominated by dissolubility salinastone-glauberite and mudstone, the second interlayer which is common to build it and dominated by clastic rock(mudstone, siltstone) with a little readily soluble salt as well as the third interlayer which is hard to build it and dominated by gypsum and anhydrite with mud and sandstone. It is easy to build salt cavern at Jintan area of Jiangsu province but hard to build it at some basins such as Wuyang city of Henan province. Some sections with thick salt bed., thin interlayer and fewwater insoluble substance are also good for build salt cavern.%中国东部岩盐层与其它岩石频繁互层.从建造储气盐穴是否有利出发,根据含盐段岩盐层夹层的不同将剖面结构类型分为三类:第1类夹层以可溶性盐类——钙芒硝及泥岩为主,该类较易建造盐穴;第2类型夹层以碎屑岩(泥岩、粉砂岩)为主,含少量易溶盐类,该类建造盐穴条件一般;第3类型夹层以石膏、硬石膏为主,含泥、砂岩,该类难以建造盐穴.在中国东部诸多盐矿区中,江苏金坛建造盐穴条件较好,易于建造盐穴.而江苏淮安、湖南衡阳、湖北潜江、河南舞阳等盆地条件较差,但在这些矿区中,选择盐层厚度相对较大,夹层较薄、水不溶物质含量较低的地段,亦可建造储气盐穴.

  10. Implications of Late Cretaceous U-Pb zircon ages of granitic intrusions cutting ophiolitic and volcanogenic rocks for the assembly of the Tauride allochthon in SE Anatolia (Helete area, Kahramanmaraş Region, SE Turkey)

    Science.gov (United States)

    Nurlu, Nusret; Parlak, Osman; Robertson, Alastair; von Quadt, Albrecht

    2016-01-01

    An assemblage of NE-SW-trending, imbricate thrust slices (c. 26 km E-W long × 6.3 km N-S) of granitic rocks, basic-felsic volcanogenic rocks (Helete volcanics), ophiolitic rocks (Meydan ophiolite) and melange (Meydan melange) is exposed near the Tauride thrust front in SE Anatolia. The volcanogenic rocks were previously assumed to be Eocene because of associated Nummulitic limestones. However, ion probe U-Pb dating of zircons extracted from the intrusive granitic rocks yielded ages of 92.9 ± 2.2-83.1 ± 1.5 Ma (Cenomanian-Campanian). The Helete volcanic unit and the overlying Meydan ophiolitic rocks both are intruded by granitic rocks of similar age and composition. Structurally underlying ophiolite-related melange includes similar-aged, but fragmented granitic intrusions. Major, trace element and rare earth element analyses coupled with electron microprobe analysis of the granitic rocks show that they are metaluminus to peraluminus and calc-alkaline in composition. A magmatic arc setting is inferred from a combination of tectonomagmatic discrimination, ocean ridge granite-normalized multi-element patterns and biotite geochemistry. Sr-Nd-Pb isotope data further suggest that the granitoid rocks were derived from variably mixed mantle and crustal sources. Granitic rocks cutting the intrusive rocks are inferred to have crystallized at ~5-16 km depth. The volcanogenic rocks and granitic rocks originated in a supra-subduction zone setting that was widely developed throughout SE Anatolia. Initial tectonic assembly took place during the Late Cretaceous probably related to northward subduction and accretion beneath the Tauride continent (Keban and Malatya platforms). Initial tectonic assembly was followed by exhumation and then transgression by shelf-depth Nummulitic limestones during Mid-Eocene, as documented in several key outcrops. Final emplacement onto the Arabian continental margin took place during the Early Miocene.

  11. The Rock Cycle

    Science.gov (United States)

    Singh, Raman J.; Bushee, Jonathan

    1977-01-01

    Presents a rock cycle diagram suitable for use at the secondary or introductory college levels which separates rocks formed on and below the surface, includes organic materials, and separates products from processes. (SL)

  12. Lithological 3D grid model of the Vuonos area built by using geostatistical simulation honoring the 3D fault model and structural trends of the Outokumpu association rocks in Eastern Finland

    Science.gov (United States)

    Laine, Eevaliisa

    2015-04-01

    The Outokumpu mining district - a metallogenic province about 100 km long x 60 km wide - hosts a Palaeoproterozoic sulfide deposit characterized by an unusual lithological association. It is located in the North Karelia Schist Belt , which was thrust on the late Archaean gneissic-granitoid basement of the Karelian craton during the early stages of the Svecofennian Orogeny between 1.92 and 1.87 Ga (Koistinen 1981). Two major tectono-stratigraphic units can be distinguished, a lower, parautochthonous 'Lower Kaleva' unit and an upper, allochthonous 'upper Kaleva' unit or 'Outokumpu allochthon'. The latter consists of tightly-folded deep marine turbiditic mica schists and metagraywackes containing intercalations of black schist, and the Outo¬kumpu assemblage, which comprises ca. 1950 Ma old, serpentinized peridotites surrounded by carbonate-calc-silicate ('skarn')-quartz rocks. The ore body is enclosed in the Outokumpu assemblage, which is thought to be part of a disrupted and incomplete ophiolite complex (Vuollo & Piirainen 1989) that can be traced to the Kainuu schist belt further north where the well-preserved Jormua ophiolite is ex¬posed (Kontinen 1987, Peltonen & Kontinen 2004). Outokumpu can be divided into blocks divided by faults and shear zones (Saalmann and Laine, 2014). The aim of this study was to make a 3D lithological model of a small part of the Outokumpu association rocks in the Vuonos area honoring the 3D fault model built by Saalmann and Laine (2014). The Vuonos study area is also a part of the Outokumpu mining camp area (Aatos et al. 2013, 2014). Fault and shear structures was used in geostatistical gridding and simulation of the lithologies. Several possible realizations of the structural grids, conforming the main lithological trends were built. Accordingly, it was possible to build a 3D structural grid containing information of the distribution of the possible lithologies and an estimation the associated uncertainties. References: Aatos, S

  13. 开滦矿区煤岩动力灾害的构造应力环境%Tectonic stress environment of coal and rock dynamic hazard in Kailuan mining area

    Institute of Scientific and Technical Information of China (English)

    韩军; 梁冰; 张宏伟; 朱志洁; 荣海; 张普田; 梁和平

    2013-01-01

    Using hollow inclusion method measure the in-situ stress of Kailuan mining area.In-situ stress field types,interaction behavior and the relationship between regional structure was systematically analyzed.Based on this,the inner relationship between in-situ stress field and coal and gas outburst,rockburst,water inrush and other coal and rock dynamic disaster was analyzed.Studies show that in-situ stress field in Kailuan mining area belongs to the Earth dynamical field,the horizontal tectonic stress is dominant,and it belongs to the high stress zone.In-situ stress magnitude and orientation is controlled by Kaiping syncline.Stress value is the highest in Kaiping synclinal axis section.As far away from the axis,the stress value decreases gradually.The maximum principal stress orientation and axis trend of Kaiping synclinal is approximate vertical.At the same time tectonic stress field controls coal structure,coal gas parameters,permeability and so on.In the Kailuan mining area,coal and gas outburst and rock burst occurred in synclinal axis section of Kaiping where stress value is highest,water inrush occurred in the Kaiping syncline wing where stress value is the lowest.Coal and rock dynamic disaster in Kailuan mining area is in the unified tectonic stress environment.%运用空心包体地应力测量方法进行了开滦矿区地应力测试,系统分析了开滦矿区地应力场的类型、作用特征及其与区域构造的关系,在此基础上分析了开滦矿区煤与瓦斯突出、冲击地压和底板突水等煤岩动力灾害与矿区地应力场之间的内在关系.研究表明开滦矿区地应力场属于大地动力场,地应力以水平构造应力为主导,且属于高应力区.矿区地应力场的量值和方位受开平向斜的控制,开平向斜轴部区域应力值最高,随着远离轴部,应力值逐渐降低;最大主应力方位与开平向斜轴部走向近似垂直.构造应力场对开滦矿区煤体结构、瓦斯参数、煤体渗

  14. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  15. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  16. 灰岩地区复杂地质的岩土工程勘察措施%On survey measures in rock engineering with complicated geological features in limestone areas

    Institute of Scientific and Technical Information of China (English)

    张毅; 房明

    2012-01-01

    通过对灰岩地区特殊地层的特征分析,研究了软塑状态灰岩残积土和溶蚀灰岩两种地层对实际岩土工程勘察的影响、鉴别时应注意的问题及相应措施,研究结果对于灰岩地区的岩土工程勘察具有一定的指导作用和现实意义。%According to the analysis of the features for the special stratum in limestone area, the paper researches the influence of the two layers of the limestone residual soil in soft plastic condition and corroded limestone on the engineering survey of the rock projects, indicates some attentive problems and respective measures, and indicates it can instruct the limestone engineering survey in the limestone areas and have some realistic meaning.

  17. Rock History and Culture

    OpenAIRE

    Gonzalez, Éric

    2013-01-01

    Two ambitious works written by French-speaking scholars tackle rock music as a research object, from different but complementary perspectives. Both are a definite must-read for anyone interested in the contextualisation of rock music in western popular culture. In Une histoire musicale du rock (i.e. A Musical History of Rock), rock music is approached from the point of view of the people – musicians and industry – behind the music. Christophe Pirenne endeavours to examine that field from a m...

  18. 高海拔地区土石坝技术研究%Study of Key Technology of Earth-Rock Dam in High Altitude Areas

    Institute of Scientific and Technical Information of China (English)

    张宝琼; 林赛; 陈红齐

    2014-01-01

    香格里拉县桑那水库是云南省第一座在高海拔3300 m的高寒地区修建的中型水库,当地冬季气温低(最低气温-27.4℃),对坝基开挖、填筑、混凝土浇筑施工带来很大影响,设计提出:1)混凝土盖板及坝基保护采取引水保护,水与岸坡结合部位易形成冰冻,对这部分采取塑料薄膜加石碴覆盖;2)土料避开低温期施工,在施工中随时检查粘土含水量,在料场采取挖排水沟,开挖过的土料场上以及填筑好的防渗心墙上覆盖三色塑料薄膜加渣料作保护等保温防冻措施;3)在永久暴露混凝土表面配置温度钢筋,浇筑混凝土时掺入抗冻剂、减水剂、速凝剂,同时采取保温措施。%Located in Shangri-La county,Sangna reservoir, a medium-sized water-conservancy project,is the first medium reservoir built in extremely cold areas at an altitude of 3 300 meters. The local temperature in winter is low (the minimum temperature is 27.4 degrees),which severely affects the founda-tion excavation,filling and concrete pouring for the damming The design in this paper proposes the following countermeasures:1) we could use water to protect the concrete cover and dam foundation;and cover the combination parts between water and bank(where freezing can be easily formed)with plastic film and ballast;2)As for the earth material,we could avoid construct-ing in low temperatures and check the clay moisture frequently during construction;and dig ditches in the stock field and cover the field for anti-freezing protection with three-color plastic film and ballast;3)we could take measures to keep the concrete warm in the process of pouring by mixing it with antifreeze agent,water reducing agent and at the same time use temperature rebar on the surface of the permanent exposed concrete.

  19. 西藏申扎地区晚古生代地层岩石磁学研究%Rock Magnetism of the Late Paleozoic in Xainza area of Tibet,West China

    Institute of Scientific and Technical Information of China (English)

    程鑫; 闫昭圣; 鱼磊; 彭喜明; 魏娜娜; 吴汉宁; 郭强; 侯宝宁; 王宝江; 康伟伟; 梁利平; 石月; 刘钊

    2012-01-01

    目的 研究西藏申扎地区晚古生代地层载磁矿物特征,为构造磁学等提供依据.方法 运用饱和等温剩磁( SIRM),三轴等温剩磁(SIRM)热退磁,磁化率-温度(x-T)曲线和NRM热退磁实验等方法进行综合分析.结果 中—上二叠统样品中含较多针铁矿、赤铁矿;下二叠统和石炭系样品中以磁铁矿为主;泥盆系样品中富集铁硫化物.结论 该套沉积地层中具有不同磁学特征的磁性矿物共生组合,可能导致岩石剩磁获得过程相对复杂;剖面上磁性矿物组合的变化,蕴含着沉积环境演化的信息.%Aim The Gandise block located in the northern margin of Gondwana continent. Gandise marine depos-its can help to trace evolutionary history of the Paleo-Tethys in northern Gondwana. Late Paleozoic successions, yielding diversified fossils, are well-exposed in the Xainza area, located in the central part of the Gandise block. Paleozoic strata seen in Zakang of Xainza is known as the best developed in northern Tibet and would provide key insights into the study of Paleozoic tectonic movement and evolution of the Qinghai-Tibet Plateau. This study pro-vides new insights for studying paleomagnetism and magnetostratigraphy in the Xainza area of Tibet, west China. Methods Rock Magnetism experiments, including progressive acquisition of IRM, thermal demagnetization of a three-component IRM, temperature-dependent magnetic susceptibility measurements, and the thermal demagnetiza- tion, were conducted on the Late Paleozoic deposits recovered from the Zakang section. Results The results show that middle and late Permian sediments have high contents of goethite and hematite; early Permian and Carbonifer-ous sediments are dominated by magnetite; and Devonian sediments are rich in ferromagnetic iron sulfides. Conclu-sion The diversified magnetic mineral paragenesis in a set of sedimentary strata, may lead to the rock IRM acqui-sition a relatively complex process; magnetic mineral

  20. The Purisima Formation and related rocks (upper Miocene - Pliocene), greater San Francisco Bay area, central California; review of literature and USGS collection now housed at the Museum of Paleontology, University of California, Berkeley

    Science.gov (United States)

    Powell, C.L.

    1998-01-01

    Sedimentary rocks more than 1.6 kilometers thick are attributed to the upper Miocene to upper Pliocene Purisima Formation in the greater San Francisco Bay area. These rocks occur as scattered, discontinuous outcrops from Point Reyes National Seashore in the north to south of Santa Cruz. Lithologic divisions of the Formation appear to be of local extent and are of limited use in correlating over this broad area. The Purisima Formation occurs in several fault-bounded terranes which demonstrate different stratigraphic histories and may be found to represent more than a single depositional basin. The precise age and stratigraphic relationship of these scattered outcrops are unresolved and until they are put into a stratigraphic and paleogeographic context the tectonic significance of the Purisima Foramtion can only be surmised. This paper will attempt to resolve some of these problems. Mollusks and echinoderms are recorded from the literature and more than 70 USGS collections that have not previously been reported. With the exception of one locality, the faunas suggest deposition in normal marine conditions at water depths of less than 50 m and with water temperatures the same or slightly cooler than exist along the present coast of central California. The single exception is a fauna from outcrops between Seal Cove and Pillar Point, where both mollusks and foraminifers suggest water depths greater than 100 m. Three molluscan faunas, the La Honda, the Pillar Point, and the Santa Cruz, are recognized based on USGS collections and published literature for the Purisima Formation. These biostratigraphically distinct faunas aid in the correlation of the scattered Purisima Formation outcrops. The lowermost La Honda fauna suggests shallow-water depths and an age of late Miocene to early Pliocene. This age is at odds with a younger age determination from an ash bed in the lower Purisima Formation along the central San Mateo County coast. The Pillar Point fauna contains only a

  1. Quantification of rock fall processes on recently deglaciated rock slopes, Gepatsch glacier, Tyrol (Austria)

    Science.gov (United States)

    Vehling, Lucas; Rohn, Joachim; Moser, Michael

    2014-05-01

    The recently deglaciated area in alpine glacier forefields is characterized by intensified mass movement processes in particular debris flows, shallow landslides and rockfalls. Due to enhanced geomorphic activity, rock slopes adjacent to shrinking glaciers contribute in a substantial way to the sediment budget. In this study, direct measurements of rock fall intensity are conducted by rock fall collector nets and natural sediment traps. The study area is a high mountain (1750-3520m a.s.l) catchment, which is recently about 30% glaciated. The extension of the Gepatsch glacier has been reducing since the little ice age maximum in the mid of the 19th century with an average annual shrinking rate of a few decameters at its tongue. The first results of the direct measurements demonstrate that on the recently deglaciated rock slopes, rock fall intensity is at least one order of magnitude higher (2,38-6,64 g/m2/d - corresponding backweathering rate: 0,3-0,9 mm/a) than on rock slopes which had has ice free since the last Pleistocene deglaciation (0,04-0,38 g/m2/d - backweathering rate: 0,005-0,05 mm/a). The highest rock fall intensity is attributed to the recent deglaciated rock slopes which are located close to larger fault systems (>60 g/m2/d - backweathering rate: >8 mm/a). Rock fall intensity shows also considerable intra-annual variations which are related to cold climate weathering processes and rainstorm activity.

  2. 上扬子地区早三叠世异常碳酸盐岩的分类与特征%Classification and characters of the Early Triassic anomalous carbonate rocks in Upper Yangtze Area

    Institute of Scientific and Technical Information of China (English)

    时志强; 安红艳; 伊海生; 张华; 曾德勇

    2011-01-01

    The anomalous carbonates of the late period of Late Permian and Early Triassic in the Upper Yangtze Area can be divided into three main types by genesis: A—biogenic anomalous carbonate rocks, B—abiogenetic (chemical and hydrodynamic ) anomalous carbonate rocks, C—multi-genetic anomalous carbonate rocks. Eight specific sorts of the anomalous carbonate rocks can be further distinguished, including microbiolite, brecciform limestone, flat-pebble limestone, ribbon limestone, thinbedded or laminated argillaceous limestone, oolitic limestone and 2 kinds of vermiculate limestone ( Type a and Type b). The extreme palaeoceanic environment and paleoclimatic conditions are the basis of the development of the anomalous carbonate rocks (mainly anachronistic facies) around P/T boundary. After the P/T mass extinction, the destruction of benthonic animals living on the surface of marine sediments was nearly stopped and the ocean currents were almost stagnated, meanwhile the surface layer of the sea water suffered the disturbing of megamonsoon and cyclonic storms, the algo-fungus ecosystem of euphoriczone grew and formed the wave-resistance microbiolites on the biohermal facies or on the shallow water carbonate platform. Seafloor was often affected by frequent storms which tear up the unconsolidated syngenetic carbonate ooze and thus the syngenetic pebble formed. At the same time, the particular gradient of the paleotopography intensified the development of carbonate gravity flows which might also be triggered by the storms; moreover the calcium carbonate-supersaturated sea water allowed the carbonate directly precipitating in the forms of chemical precipitation on the seafloor and the clays brought by the megamonsoon deposited together with the carbonate chemical precipitation. All the mentioned process happened at the earliest Early Triassic specific palaeoenvironment, which resulted in the appearance of the diverse anomalous carbonate deposition in the Upper Yangzte Area

  3. Principles of rock mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Turchaninov, I.A.; Iofis, M.A.; Kasparyan, E.V.

    1979-01-01

    This book presents the principles of rock mechanics in a systematic way, reflecting both the historic development and the contemporary status of theoretical and experimental techniques used for the determination of the properties and stress state of rock masses, calculation of elements of systems for exploitation of useful mineral deposits and the design of mine openings. The subject of rock mechanics is discussed and methods and basic approaches are analyzed. The most widely used methods for determining the properties of rock in specimens and in situ are described. Problems of determining the stress strain state of the rock around mine openings by both experimental and analytic methods are discussed. The primary results of the study of the stress state of rock around main, development and production openings are presented. Problems of the movement of rock due to extraction of minerals are analyzed in detail, as are the conditions and causes of the development of rock bursts and sudden release of rock and gas in both surface and underground mines. Procedures for preventing or localizing rock bursts or sudden outbursts are described. (313 refs.)

  4. 激发极化法在早前寒武纪变质岩系找水中的应用%Application of Induced Polarization Method for Groundwater Exploration in Metamorphic Rock Areas of Taishan Group

    Institute of Scientific and Technical Information of China (English)

    刘洪波; 于林松; 刘伟; 魏印涛; 王强; 于在利

    2012-01-01

    通过对在早前寒武纪变质岩系进行抗旱找水中利用地球物理勘探定井的实例分析,阐述了利用激发极化法在早前寒武纪变质岩分布区辨认含水层,确定含水层埋深,最终确定较好井位的方法。该方法对解决早前寒武纪变质岩系的干旱缺水现状有广泛深远的意义。%Through analysis on successful examples for groundwater exploration,by using geophysical prospecting method in metamorphic rock areas of Taishan group,it is regarded that the induced polarization method is very useful for identifying aquifer,determining the depth of aquifer,and determining the position of wells finally.It will play an important role in solving the needs of water in the arid region.

  5. Estimation on the effective heat extraction area of the reservoir at Hijiori hot dry rock test site; Hijiori kooon gantai ni keisei sareta jinko choryuso no kiretsumen no netsukokan menseki no suitei

    Energy Technology Data Exchange (ETDEWEB)

    Tenma, N.; Matsunaga, I.; Kuriyagawa, M. [National Inst. for Resources and Environment, Tsukuba (Japan); Yamaguchi, T. [New Energy and Industrial Technology Development Organization, Tokyo (Japan); Miyairi, M. [JAPEX Research Center, Tokyo (Japan). Technical Lab.; Zyvoloski, G.

    1994-06-25

    Tests for development of hot dry rock at Hijiori caldera (Yamagata Pref.) started in 1984 and the well SKG-2 (depth: 1,802m, 254{degree}C at well bottom) was dug. In 1986, water pressure crushing being carried out, artificial reservoir was made near the well bottom. On the reservoir, wells HDR-1 (depth: 2,206m), -2 (1,910m) and -3 (1,907m) were dug. In 1991, three month circulation test was conducted using the well SKG-2 as an injection well and other three wells as production ones. Being guessed that there exist several flow paths in the reservoir, a model for investigation was developed for each flow path using the simulation code FEMM. According to the data of temperature and flow rate at every depth (zone) in the production wells, calculations were repeated many times under various conditions. Consequently, positions and heat extraction areas of plural fractures taking part in heat exchange have been estimated. 14 refs., 11 figs., 5 tabs.

  6. Rock cavern storage of spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Won Jin; Kim, Kyung Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kwon, Sang Ki [Inha University, Incheon (Korea, Republic of)

    2015-12-15

    The rock cavern storage for spent fuel has been assessed to apply in Korea with reviewing the state of the art of the technologies for surface storage and rock cavern storage of spent fuel. The technical feasibility and economic aspects of the rock cavern storage of spent fuel were also analyzed. A considerable area of flat land isolated from the exterior are needed to meet the requirement for the site of the surface storage facilities. It may, however, not be easy to secure such areas in the mountainous region of Korea. Instead, the spent fuel storage facilities constructed in the rock cavern moderate their demands for the suitable site. As a result, the rock cavern storage is a promising alternative for the storage of spent fuel in the aspect of natural and social environments. The rock cavern storage of spent fuel has several advantages compared with the surface storage, and there is no significant difference on the viewpoint of economy between the two alternatives. In addition, no great technical difficulties are present to apply the rock cavern storage technologies to the storage of domestic spent fuel.

  7. Application of Group Drilling Pumping Test in Burnt Rocks in Dananhu Mining Area Xinjiang Uygur Autonomous Region%群孔抽水试验在新疆哈密大南湖矿区烧变岩层中的应用研究

    Institute of Scientific and Technical Information of China (English)

    张兆民; 鲁孟胜; 孙德全

    2014-01-01

    Portions of the Ⅲ burnt rocks in south part of the first mining area of northern open pit coal mine in Dananhu mine of Hami in Xinjiang should be exposed.It makes the burnt rock water become the main source of mine water filling.As showed by hydrogeological data in exploration stage,water bearing space in burnt rock area developed well with permeable capability and large storage capacity.Due to the limit of hydrogeological exploration engineering amount in exploration stage,hydrogeological condition has not been identified in detail.In order to find out water contact and the groundwater water quality changes of burnt rock,and to fully expose the hydrogeological conditions of the burnt rocks in Ⅲ burning area, group drilling pumping test has been designed.This test has identified hydrogeological conditions of burnt rocks,provided the basis for water prevention work under the condition of burnt rock.Through compre-hensive analysis,it is showed the burnt rocks in Ⅲ burning area are aquifer storage capacity type with poor supply conditions.%新疆哈密大南湖矿区北露天煤矿首采区东南部需要揭露Ⅲ火烧岩区一部分,这使得烧变岩水成为露天煤矿矿井充水的主要水源。资源勘探阶段的水文地质资料表明,烧变岩区赋水空间发育、透水能力强,储存量非常可观,但由于受资源勘探阶段水文地质勘探工程量制约,水文地质条件未能详细查明。因此为达到查明烧变岩地下水水力联系、水质变化情况,充分暴露Ⅲ火烧区烧变岩的水文地质条件的目的,设计了该次群孔抽水试验。该次试验查明了烧变岩含水层的水文地质条件,为烧变岩地质条件下防治水工作提供了依据。综合分析表明Ⅲ火烧区烧变岩为储存量型含水层,其补给条件差。

  8. Rock avalanches: significance and progress (Invited)

    Science.gov (United States)

    Davies, T. R.

    2013-12-01

    1. The probability distribution of landslide volumes follows a power-law indicating that large rock avalanches dominate the terrestrial sediment supply from mountains, and that their source area morphologies dominate mountain topography. 2. Large rock slope failures (~ 106 m3 or greater) often mobilise into rock avalanches, which can travel extraordinarily long distances with devastating effect. This hypermobility has been the subject of many investigations; we have demonstrated that it can be explained quantitatively and accurately by considering the energetics of the intense rock fragmentation that always occurs during motion of a large rock mass. 3. Study of rock avalanche debris psd shows that the energy used in creating new rock surface area during fragmentation is not lost to surface energy, but is recycled generating a high-frequency elastic energy field that reduces the frictional resistance to motion during runout. 4. Rock avalanches that deposit on glaciers can eventually form large terminal moraines that have no connection with any climatic event; unless these are identified as rock-avalanche-influenced they can confuse palaeoclimatic inferences drawn from moraine ages. Rock-avalanche-derived fines, however, can be identified in moraine debris up to ten thousand years old by the characteristic micron-scale agglomerates that form during intense fragmentation, and which are absent from purely climatically-induced moraines; there is thus a strong case for re-examining existing palaeoclimatic databases to eliminate potentially rock-avalanche-influenced moraine ages. 5. Rock avalanches (especially coseismic ones) are a serious hazard, being very destructive in their own right; they also block river valleys, forming landslide dams and potentially devastating dambreak floods, and subsequent severe decade-scale aggradation of downstream fans and floodplains. Rock avalanches falling into lakes or fiords can cause catastrophic tsunami that pose a serious risk to

  9. Selected references on alkalic igneous rocks of the United States

    Energy Technology Data Exchange (ETDEWEB)

    Hall, C.R. (comp.)

    1976-01-01

    A compilation of references is presented providing background information on rock and mineral associations, geochemistry, geophysics, structural relationships, and geochronology of sialic, feldspathoidal, and some mafic alkalic igneous rock exposures in the US. Their locations and major characteristics are cited. No implication regarding U potential in these areas is intended. The first part of the bibliography provides general references to overall features of alkaline igneous rocks by region. The second part is a compilation of references on alkalic igneous rocks by state or groups of states. The third part provides information on rock type, age, and location for most of the references cited in part two. (JSR)

  10. Assessment of abrasiveness for research of rock cutting

    Directory of Open Access Journals (Sweden)

    Milan Labaš

    2012-12-01

    Full Text Available Rock abrasiveness is ability of rock to wear down the working tool during the mutual interaction between the working indentorand the rock in the mechanical rock cutting process. The cutting indentor is worn down during the interaction, which changes itsgeometric dimensions causing the enlargement of a contact area between the tool and the rock surface. The changes in these dimensionsconsequently alter the rate of advance of the drilling machine and the specific cutting energy. We have determined the abrasivenessaccording to the norm ON 44 1121 (1982 on the testing device constructed at the Institute of Geotechnics SAS.

  11. Soft rocks in Argentina

    Institute of Scientific and Technical Information of China (English)

    Giambastiani; Mauricio

    2014-01-01

    Soft rocks are a still fairly unexplored chapter in rock mechanics. Within this category are the clastic sedimentary rocks and pyroclastic volcanic rocks, of low to moderate lithification (consolidation, cemen-tation, new formed minerals), chemical sedimentary rocks and metamorphic rocks formed by minerals with Mohs hardness less than 3.5, such as limestone, gypsum, halite, sylvite, between the first and phyllites, graphitic schist, chloritic shale, talc, etc., among the latter. They also include any type of rock that suffered alteration processes (hydrothermal or weathering). In Argentina the study of low-strength rocks has not received much attention despite having extensive outcrops in the Andes and great impact in the design criteria. Correlation between geomechanical properties (UCS, deformability) to physical index (porosity, density, etc.) has shown promising results to be better studied. There are many studies and engineering projects in Argentina in soft rock geological environments, some cited in the text (Chihuído dam, N. Kirchner dam, J. Cepernic Dam, etc.) and others such as International Tunnel in the Province of Mendoza (Corredor Bioceánico), which will require the valuable contribution from rock mechanics. The lack of consistency between some of the physical and mechanical parameters explored from studies in the country may be due to an insufficient amount of information and/or non-standardization of criteria for testing materials. It is understood that more and better academic and professional efforts in improv-ing techniques will result in benefits to the better understanding of the geomechanics of weak rocks.

  12. 子长—蟠龙地区长1半深—深湖相沉积及其生油意义%Chang 1 lacustrine sediments and oil-source-rock conditions in Zichang- Panlong Area

    Institute of Scientific and Technical Information of China (English)

    张惠; 孟祥振; 蒲仁海; 孟鹄

    2012-01-01

    disconformity between Triassic and Jurassic. The isopach map of dark shales indicates that the lacustrine facies in Zichang-Panlong region lengthen north-south 120 km and widen east-west 60 km. Moreover, the study area is only the middle part of the eastern original lake which should extend westward, northward and southward much more distances and cover double area of the present defined lacustrine portion. Chang 1 dark shales possess rich organic matter and the organic carbon is more than 4% . Most of them belong to Ⅱ1 type of kerogen which has evolved to the maturated period. Therefore the lacustrine rocks conform to the conditions of high quality of oil source rocks. Conclusion The widespread Chang 1 lacustrine rocks may have great significance to the information of Chang 2 and Jurassic reservoir in Ordos Basin.

  13. Mineralogy and geochemistry of trace metals and REE in volcanic massive sulfide host rocks, stream sediments, stream waters and acid mine drainage from the Lousal mine area (Iberian Pyrite Belt, Portugal)

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira da Silva, E. [GeoBioTec - GeoBiosciences, Technologies and Engineering Research Center, Departamento de Geociencias, Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal)], E-mail: eafsilva@ua.pt; Bobos, I. [Departamento de Geologia, Faculdade de Ciencias da Universidade do Porto, Rua Campo Alegre 687 4169-007 Porto (Portugal); Xavier Matos, J. [Centro de Estudos Geologicos e Mineiros de Beja, Rua Frei Amador Arrais No. 39 r/c, Apartado 104, 7801-902 Beja (Portugal); Patinha, C.; Reis, A.P.; Cardoso Fonseca, E. [GeoBioTec - GeoBiosciences, Technologies and Engineering Research Center, Departamento de Geociencias, Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal)

    2009-03-15

    Acid mine drainage represents a major source of water pollution in the Lousal area. The concentrations of trace metals and the rare earth elements (REE) in the host rocks, stream sediment, surface waters and acid mine drainage (AMD) associated with abandoned mine adits and tailings impoundments were determined, in order to fingerprint their sources and to understand their mobility and water-rock interaction. The results show that the Fe-SO{sub 4}-rich acid waters vary substantially in composition both spatially and seasonally. These waters include very low pH (mostly in the range 1.9-3.0), extreme SO{sub 4} concentrations (4635-20,070 mg L{sup -1}SO{sub 4}{sup 2-}), high metal contents (Fe, Al, Cu, Zn and Mn) and very high REE contents. The trace metal concentrations decrease downstream from the discharge points either due to precipitation of neoformed phases or to dilution. The North-American shale composite (NASC)-normalized patterns corresponding to sediment from one stream (Corona stream) show a flat tendency or are slightly enriched in light-REE (LREE). The NASC-normalized patterns corresponding to acidic mine waters show enrichment in the middle REE (MREE) with respect to the LREE and heavy REE (HREE). Moreover, the REE concentrations in acidic mine waters are 2 or 3 orders of magnitude higher than those of the surface waters. Changes of REE concentrations and variation of Eu anomaly show two spatially distinct patterns: (a) pond and spring waters with higher REE concentrations (ranging from 375 to 2870 {mu}g L{sup -1}), that records conspicuous negative Eu anomaly, and (b) seeps from tailings impoundments corresponding to lower REE concentrations than the first pattern (ranging from 350 to 1139 {mu}g L{sup -1}) with typically negative Eu anomaly. The stream water samples collected from the impacted stream during the spring show a low pH (2.8-3.1) and contain high concentrations of Fe and trace elements (up to 61 mg L{sup -1}). Also, temporal variations of

  14. Rock Cycle Roulette.

    Science.gov (United States)

    Schmidt, Stan M.; Palmer, Courtney

    2000-01-01

    Introduces an activity on the rock cycle. Sets 11 stages representing the transitions of an earth material in the rock cycle. Builds six-sided die for each station, and students move to the stations depending on the rolling side of the die. Evaluates students by discussing several questions in the classroom. Provides instructional information for…

  15. Annual Post-Closure Inspection and Monitoring Report for Corrective Action Unit 329: Area 22 Desert Rock Airstrip Fuel Spill, Nevada Test Site, Nevada, with Errata Sheet, Rev. No.: 1

    Energy Technology Data Exchange (ETDEWEB)

    Wickline, Alfred

    2007-01-01

    This report presents the data collected during field activities and quarterly soil-gas sampling activities conducted from May 9, 2005, through May 20, 2006, at Corrective Action Unit (CAU) 329, Area 22 Desert Rock Airstrip (DRA) Fuel Spill; Corrective Action Site (CAS) 22-44-01, Fuel Spill. The CAU is located at the DRA, which is located approximately two miles southwest of Mercury, Nevada. A risk evaluation was added to the scope of the project to determine if the residual concentration of the hazardous constituents of JP4 pose an unacceptable risk to human health or the environment and if a corrective action was required at the site, because the current quarterly monitoring program is not expected to yield a rate constant that could be used effectively to determine a biodegradation rate for total petroleum hydrocarbons (TPH) in less than the initial five years outlined in the CR. Additionally, remediation to the Tier 1 action level for TPH is not practical or technically feasible due to the depth of contamination. Field activities were conducted under the Addendum to the CR to collect sufficient data to determine the rate of biodegradation for TPH contamination at CAU 329 to support closure requirements. Reconstruction of the monitoring system at the site and quarterly soil-gas sampling were conducted to collect the required data. Because existing Wells DRA-0 and DRA-3 were determined to be insufficient to provide adequate data, soil-gas monitoring Wells DRA-10 and DRA-11 were installed. Two soil-gas sampling events were conducted to establish a baseline for the site, and subsequent quarterly sampling was conducted as part of the quarterly soil-gas sampling program. In addition, soil samples were collected during well drilling activities so comparisons might be made between the initial soil contamination levels in 2000 and the concentrations present at the time of the well installation.

  16. ROCK GLACIERS IN THE KOLYMA HIGHLAND

    Directory of Open Access Journals (Sweden)

    A. A. Galanin

    2012-01-01

    Full Text Available Based on remote mapping and field studies inGrand Rapids, Tumansky,Hasynsky,Del-Urechen Ridges as well as Dukchinsky and Kilgansky Mountain Massifs there were identified about 1160 landforms which morphologically are similar to the rock glaciers or they develop in close association with them. Besides tongue-shaped cirque rock glaciers originated due to ablation, a large number of lobate-shaped slope-associated rock glaciers were recognized. Significant quantity of such forms are developing within the active neotectonic areas, in zones of seismic-tectonic badland and in association with active earthquakes-controlling faults. Multiplication of regional data on volcanic-ash-chronology, lichenometry, Schmidt Hammer Test, pollen spectra and single radiocarbon data, most of the active rock glaciers were preliminary attributed to the Late Holocene.

  17. Geotechnical basis for underground energy storage in hard rock

    Science.gov (United States)

    Farquhar, O. C.

    1982-03-01

    Underground pumped hydroelectric storage requires the excavation of caverns in hard rock. Hard rock caverns, also, are one option for compressed air stoage. Preliminary design studies for both technologies at a specific site were completed. The geotechnical aspects of these storage systems are discussed from a generic viewpoint. Information about effective use of hard rock openings, including tunnels and shafts, comes mainly from other types of underground projects. These are power houses for hydroelectric and conventional pumped storage schemes, as well as transportation facilities and mines. Rock strength, support, instrumentation, costs, management, and experimental work are among the items considered. Mapping of geologic structures, rock fragmentation, and rock mass properties is also discussed. The general conclusions are that rock types favorable for underground energy storage are present at suitable depths in many areas and that they can be identified by adequate geotechnical exploration prior to detailed design.

  18. Impact of fluid-rock chemical interactions on tracer transport in fractured rocks.

    Science.gov (United States)

    Mukhopadhyay, Sumit; Liu, H-H; Spycher, N; Kennedy, B M

    2013-11-01

    In this paper, we investigate the impact of chemical interactions, in the form of mineral precipitation and dissolution reactions, on tracer transport in fractured rocks. When a tracer is introduced in fractured rocks, it moves through the fracture primarily by advection and it also enters the stagnant water of the surrounding rock matrix through diffusion. Inside the porous rock matrix, the tracer chemically interacts with the solid materials of the rock, where it can precipitate depending on the local equilibrium conditions. Alternatively, it can be dissolved from the solid phase of the rock matrix into the matrix pore water, diffuse into the flowing fluids of the fracture and is advected out of it. We show that such chemical interactions between the fluid and solid phases have significant impact on tracer transport in fractured rocks. We invoke the dual-porosity conceptualization to represent the fractured rocks and develop a semi-analytical solution to describe the transient transport of tracers in interacting fluid-rock systems. To test the accuracy and stability of the semi-analytical solution, we compare it with simulation results obtained with the TOUGHREACT simulator. We observe that, in a chemically interacting system, the tracer breakthrough curve exhibits a pseudo-steady state, where the tracer concentration remains more or less constant over a finite period of time. Such a pseudo-steady condition is not observed in a non-reactive fluid-rock system. We show that the duration of the pseudo-state depends on the physical and chemical parameters of the system, and can be exploited to extract information about the fractured rock system, such as the fracture spacing and fracture-matrix interface area.

  19. Southern Carpathian rock glaciers: Inventory, distribution and environmental controlling factors

    Science.gov (United States)

    Onaca, Alexandru; Ardelean, Florina; Urdea, Petru; Magori, Brigitte

    2017-09-01

    Rock glaciers are valuable diagnostic landforms indicating permafrost creeping during their genesis and activity. Based on the analysis of high quality air-orthophoto and field work, a first polygon-based inventory of rock glaciers from the Southern Carpathians has been elaborated. In total, 306 rock glaciers were included in the inventory comprising 79 debris and 227 talus rock glaciers. Most of these landforms were classified as relict (258), while only 48, covering 2.81 km2, were considered intact. The size of rock glaciers, considered as a proxy for past environmental conditions, and the relationships with the predictor variables (lithology, aspect, contributing area, geographic coordinates, elevation and slope range) were analysed using bivariate statistics, analysis of variance (ANOVA) and various post hoc tests. The statistical analysis revealed that the rock glaciers occurring in the highest mountain ranges in areas composed of granites and granodiorites are considerably larger than the others, because their duration of activity is greater. Strong dependences between rock glacier size and other topographic attributes (contributing area, aspect and slope range) were also confirmed. The rock glacier distribution in the Southern Carpathians is clearly controlled by topography, lithology and debris availability. The abundance of rock glaciers increases with altitude, but their size decreases slightly. In mountain units where granites and granodiorites predominate (Retezat and Parâng Mountains), the density of rock glaciers and the mean specific area covered by these spectacular landforms are considerably higher than in other areas. The higher continentality effects of the Southern Carpathians enabled the formation of rock glaciers at substantially lower elevations than in the Alps. The mean altitude of intact rock glaciers front, which could be used as a morphological indicator of discontinuous permafrost, is located at 2088 m.

  20. CRITERIA FOR ROCK ENGINEERING FAILURE

    Institute of Scientific and Technical Information of China (English)

    ZHUDeren; ZHANGYuzhuo

    1995-01-01

    A great number of underground rock projects are maintained in the rock mass which is subject to rock damage and failure development. In many cases, the rock. engineering is still under normal working conditions even though rock is already fails to some extent. This paper introduces two different concepts: rock failure and rock engineering failure. Rock failure is defined as a mechanical state under which an applicable characteristic is changed or lost.However, the rock engineering failure is an engineering state under which an applicable function is changed or lost. The failure of surrounding rocks is the major reason of rock engineering failure. The criterion of rock engineering failure depends on the limit of applicable functions. The rock engineering failure state possesses a corresponding point in rock failure state. In this paper, a description of rock engineering failure criterion is given by simply using a mechanical equation or expression. It is expected that the study of rock engineering failure criterion will be an optimal approach that combines research of rock mechanics with rock engineering problems.

  1. Preliminary Study on weathering and pedogenesis of carbonate rock

    Institute of Scientific and Technical Information of China (English)

    王世杰; 季宏兵; 欧阳自远; 周德全; 郑乐平; 黎廷宇

    1999-01-01

    South China is the largest continuous distribution area of carbonate rock in the world. The origin of the soils over the bedrock carbonate rock has long been a controversial topic. Here further exploration is made by taking five soil profiles as examples, which are developed over the bedrock dolomitite and limestone and morphologically located in upland in karst terrain in the central, west and north Guizhou as well as west Hunan, and proved to be the weathering profiles of carbonate rock by the research results of acid-dissolved extraction experiment of bedrock, mineralogy and trace element geochemistry. Field, mineralogical and trace element geochemical characteristics of weathering and pedogenesis for carbonate rock are discussed in detail. It is pointed out that weathering and pedogenesis of carbonate rock are important pedogenetic mechanisms for soil resources in karst area, providing a basis for further researches on the origin of soils widely overlying bedrock carbonate rocks in South China.

  2. Days of Rock

    Institute of Scientific and Technical Information of China (English)

    YUAN

    2004-01-01

    FROM last October 1 st to 3rd, at the foot of Fragrant Hill, a suburban Beijing resort famous for its flaming maple leaves in autumn, more than 20,000 rock fans indulged themselves in music for three days.

  3. Writing Rock Music Reviews.

    Science.gov (United States)

    Brown, Donal

    1980-01-01

    Suggests ways student reviewers of rock music groups can write better reviews. Among the suggestions made are that reviewers occasionally discuss the audience or what makes a particular group unique, support general comment with detail, and avoid ecstatic adjectives. (TJ)

  4. Rock kinoekraanil / Katrin Rajasaare

    Index Scriptorium Estoniae

    Rajasaare, Katrin

    2008-01-01

    7.-11. juulini kinos Sõprus toimuval filminädalal "Rock On Screen" ekraanile jõudvatest rockmuusikuid portreteerivatest filmidest "Lou Reed's Berlin", "The Future Is Unwritten: Joe Strummer", "Control: Joy Division", "Hurriganes", "Shlaager"

  5. Art on Rock

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    With sprawling deserts and serene lakes, the natural wonders of Ningxia Hui Autonomous Region have never failed totake the breath away from visitors. The areahas another major attraction, though: the Helan Mountain rock engravings.

  6. Rock kinoekraanil / Katrin Rajasaare

    Index Scriptorium Estoniae

    Rajasaare, Katrin

    2008-01-01

    7.-11. juulini kinos Sõprus toimuval filminädalal "Rock On Screen" ekraanile jõudvatest rockmuusikuid portreteerivatest filmidest "Lou Reed's Berlin", "The Future Is Unwritten: Joe Strummer", "Control: Joy Division", "Hurriganes", "Shlaager"

  7. Pop & rock / Berk Vaher

    Index Scriptorium Estoniae

    Vaher, Berk, 1975-

    2001-01-01

    Uute heliplaatide Redman "Malpractice", Brian Eno & Peter Schwalm "Popstars", Clawfinger "A Whole Lot of Nothing", Dario G "In Full Color", MLTR e. Michael Learns To Rock "Blue Night" lühitutvustused

  8. Pop & rock / Berk Vaher

    Index Scriptorium Estoniae

    Vaher, Berk, 1975-

    2001-01-01

    Uute heliplaatide Redman "Malpractice", Brian Eno & Peter Schwalm "Popstars", Clawfinger "A Whole Lot of Nothing", Dario G "In Full Color", MLTR e. Michael Learns To Rock "Blue Night" lühitutvustused

  9. Petrology and geochemistry characteristics of the Cu-Ni sulfide deposits of the 3rd rocks in Hongqiling area, Jilin%吉林红旗岭矿区3号岩体铜镍硫化物矿床岩石学和地球化学特征研究

    Institute of Scientific and Technical Information of China (English)

    董国振; 叶满华; 戴晓光; 孙超

    2012-01-01

    红旗岭矿区3号岩体由辉长岩相、辉岩相组成,矿体产于辉岩相中.岩体镁铁比值(m/f)为1.27 ~4.93,平均值为3.54,属铁质超基性岩.岩体稀土配分模式呈右倾的轻稀土富集型.矿石硫同位素组成(δ34S)为-1.7‰~+0.3‰,平均值为-0.68‰,与陨石硫同位素组成一致.其岩体岩相组成、赋矿岩石和矿物成分、岩石化学、主成矿元素、稀土元素、硫同位素组成特征,与矿区内1号、7号、2号、9号等含矿岩体具有比较明显的一致性,反映了矿区内含矿岩体形成于同一期构造岩浆活动,岩浆及成矿物质来源具有同源性.%The rocks of the 3rd ore-bearing rocks in Hongqiling area are composed of gabbro and pyroxenite and Ore-bearing come from pyroxenite facies. The ratio of Mg/Fe( m/f) is 1,27 -4.93 ,with a 3.54 average, which indicates that that are iron ultramafic rocks. The REE patterns of the rocks show a relatively right deviation and enriched in LREE. Sulphur isotope of the ore was - 1.7%o ~ + 0.3%o,with a -0.68%o average, which is identical with the sulphur isotope of meteorolite.The 3rd ore-bearing rocks have apparent consistent and similarity with the other ore-bearing rocks( the 1st,the 2nd,the 7th,and the 9th)in petrofacies,ore-bearing rocks and its mineral components, petrochemis try features, main ore elements, REE features and its patterns, sulfur isotope compon ent. All the ore-bearing rocks in the ore field formed in the same tectono-magmatic activities. Magma and mineralization have the same sources,and formed the same ore deposits.a

  10. Rock avalanches on glaciers

    OpenAIRE

    Shugar, Daniel

    2011-01-01

    This thesis examines relations between rock avalanches and the glaciers on which they are deposited. I have attempted to understand a geophysical phenomenon from two viewpoints: sedimentology and glaciology. The contributions are both methodological, and practical. I have used a GIS to quantify debris sheet geomorphology. A thorough characterization of rock avalanche debris is a necessary step in understanding the flow mechanics of large landslide. I have also developed a technique for solvin...

  11. Evolution of sedimentary rock formation of a rock association level

    Science.gov (United States)

    Kuznetsov, V. G.

    2017-07-01

    The evolution of sedimentary rock formation of a highly organized level (paragenetic rock associations) is more complex than that of a poorly organized level (rocks). Subjacent rock associations are established for the entire geological evolution of the Earth: they varied in time and were obsolescent or, in contrast, nascent and momentary. A certain cyclicity of evolution is identified along with directed changes.

  12. Brine and Gas Flow Patterns Between Excavated Areas and Disturbed Rock Zone in the 1996 Performance Assessment for the Waste Isolation Pilot Plant for a Single Drilling Intrusion that Penetrates Repository and Castile Brine Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    ECONOMY,KATHLEEN M.; HELTON,JON CRAIG; VAUGHN,PALMER

    1999-10-01

    The Waste Isolation Pilot Plant (WIPP), which is located in southeastern New Mexico, is being developed for the geologic disposal of transuranic (TRU) waste by the U.S. Department of Energy (DOE). Waste disposal will take place in panels excavated in a bedded salt formation approximately 2000 ft (610 m) below the land surface. The BRAGFLO computer program which solves a system of nonlinear partial differential equations for two-phase flow, was used to investigate brine and gas flow patterns in the vicinity of the repository for the 1996 WIPP performance assessment (PA). The present study examines the implications of modeling assumptions used in conjunction with BRAGFLO in the 1996 WIPP PA that affect brine and gas flow patterns involving two waste regions in the repository (i.e., a single waste panel and the remaining nine waste panels), a disturbed rock zone (DRZ) that lies just above and below these two regions, and a borehole that penetrates the single waste panel and a brine pocket below this panel. The two waste regions are separated by a panel closure. The following insights were obtained from this study. First, the impediment to flow between the two waste regions provided by the panel closure model is reduced due to the permeable and areally extensive nature of the DRZ adopted in the 1996 WIPP PA, which results in the DRZ becoming an effective pathway for gas and brine movement around the panel closures and thus between the two waste regions. Brine and gas flow between the two waste regions via the DRZ causes pressures between the two to equilibrate rapidly, with the result that processes in the intruded waste panel are not isolated from the rest of the repository. Second, the connection between intruded and unintruded waste panels provided by the DRZ increases the time required for repository pressures to equilibrate with the overlying and/or underlying units subsequent to a drilling intrusion. Third, the large and areally extensive DRZ void volumes is a

  13. Weathering of rock 'Ginger'

    Science.gov (United States)

    1997-01-01

    One of the more unusual rocks at the site is Ginger, located southeast of the lander. Parts of it have the reddest color of any material in view, whereas its rounded lobes are gray and relatively unweathered. These color differences are brought out in the inset, enhanced at the upper right. In the false color image at the lower right, the shape of the visible-wavelength spectrum (related to the abundance of weathered ferric iron minerals) is indicated by the hue of the rocks. Blue indicates relatively unweathered rocks. Typical soils and drift, which are heavily weathered, are shown in green and flesh tones. The very red color in the creases in the rock surface correspond to a crust of ferric minerals. The origin of the rock is uncertain; the ferric crust may have grown underneath the rock, or it may cement pebbles together into a conglomerate. Ginger will be a target of future super-resolution studies to better constrain its origin.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  14. The Formation and Distribution of the Marine Hydrocarbon Source Rock in the Tarim Basin, NW China

    Institute of Scientific and Technical Information of China (English)

    CAI Xiyuan; WANG Yi

    2008-01-01

    There are significant differences in type and distribution between marine source rock and continental source rock. According to the lithology, the Cambrian-Ordovician source rock in the Tarim basin is divided into two types: the carbonate source rock and the mud source rock. The two sets of source rocks are developed mainly in three sets of formations, Lower-Middle Cambrian carbonate source rock and mud source rock, Lower-Middle Ordovician mud source rock and Upper Ordovician lime mud source rock. The stratigraphic and areal distributions of the source rocks are controlled by the altitude and the sedimentary facies respectively. The mud source rock is developed in slope-semi deep sea environment. The source rock developed in the slope sedimentary environment is related with the anoxic environment and the one developed in semi deep sea has a close relationship with the up-flowing sea water. The carbonate source rock is developed mainly in platform slope of highstand systems tract and it is usually intimately associated with the salt rock. The Lower-Middle Cambrian carbonate source rock is developed mainly in the Bachu, Tazhong, Taugguzibasi and Yingmaili areas. The Lower-Middle Cambrian mud source rock is mainly developed in the areas east of the line of Kunan 1-Tadong 1. The Lower-Middle Ordovician mud source rock is developed mainly in the east slope of the Manjiaer depression. The carbonate source rock of Early Ordovician is developed mainly in the platform slope of highstand systems tract, such as the south margin of Tabei, the north slope of Tazhong, the Bachu area and Keping area.

  15. Automated sliding susceptibility mapping of rock slopes

    Directory of Open Access Journals (Sweden)

    A. Günther

    2004-01-01

    Full Text Available We present a suite of extensions for ARCVIEW GIS™ (ESRI that allows to map the spatial distribution of first-order mechanical slope-properties in hard rock terrain, e.g. for large slope areas like water reservoir slopes. Besides digital elevation data, this expert-system includes regional continuous grid-based data on geological structures that might act as potential sliding or cutoff planes for rockslides. The system allows rapid automated mapping of geometrical and kinematical slope properties in hard rock, providing the basis for spatially distributed deterministic sliding-susceptibility evaluations on a pixel base. Changing hydrostatic slope conditions and rock mechanical parameters can be implemented and used for simple predictive static stability calculations. Application is demonstrated for a study area in the Harz Mts., Germany.

  16. Cap rock efficiency of geothermal systems in fold-and-thrust belts: Evidence from paleo-thermal and structural analyses in Rosario de La Frontera geothermal area (NW Argentina)

    Science.gov (United States)

    Maffucci, R.; Corrado, S.; Aldega, L.; Bigi, S.; Chiodi, A.; Di Paolo, L.; Giordano, G.; Invernizzi, C.

    2016-12-01

    Cap rock characterization of geothermal systems is often neglected despite fracturing may reduce its efficiency and favours fluid migration. We investigated the siliciclastic cap rock of Rosario de La Frontera geothermal system (NW Argentina) in order to assess its quality as a function of fracture patterns and related thermal alteration. Paleothermal investigations (XRD on fine-grained fraction of sediments, organic matter optical analysis and fluid inclusions on veins) and 1D thermal modelling allowed us to distinguish the thermal fingerprint associated to sedimentary burial from that related to fluid migration. The geothermal system is hosted in a Neogene N-S anticline dissected by high angle NNW- and ENE-striking faults. Its cap rock can be grouped into two quality categories: rocks acting as good insulators, deformed by NNW-SSE and E-W shear fractures, NNE-SSW gypsum- and N-S-striking calcite-filled veins that developed during the initial stage of anticline growth. Maximum paleo-temperatures (< 60 °C) were experienced during deposition to folding phases. rocks acting as bad insulators, deformed by NNW-SSE fault planes and NNW- and WNW-striking sets of fractures associated to late transpressive kinematics. Maximum paleo-temperatures higher than about 115 °C are linked to fluid migration from the reservoir to surface (with a reservoir top at maximum depths of 2.5 km) along fault damage zones. This multi-method approach turned out to be particularly useful to trace the main pathways of hot fluids and can be applied in blind geothermal systems where either subsurface data are scarce or surface thermal anomalies are lacking.

  17. 塔里木盆地塔中地区奥陶系碳酸盐岩封盖性能%Sealing capacity of the Ordovician carbonate rocks in Tazhong area,the Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    钱一雄; 何治亮; 陈强路; 李慧莉; 路清华; 蔡习尧; 尤东华

    2012-01-01

    利用5口区探井碳酸盐岩的矿物组成、微孔特征和测井资料等对塔里木盆地塔中地区奥陶系碳酸盐岩封盖性能进行了研究.结果表明,塔中奥陶系良里塔格组和鹰山组位于中成岩A-B亚段和晚成岩A亚段.良里塔格组中颗粒灰岩的突破压力为1.81 ~ 29.76 MPa,突破半径为13.89~77.35 nm,变化较大;泥灰岩的突破压力为14.33 MPa,突破半径为9.77 nm;含泥质条带泥晶灰岩的突破压力为3.15 ~5.41 MPa,突破半径为25.90~44.51 nm.鹰山组灰云岩的突破压力为0.98 ~ 10.35 MPa,突破半径为13.52~142.60 nm.因此,良里塔格组泥灰岩、部分颗粒灰岩及鹰山组云灰岩均有一定的封盖能力,其连续厚度大于5 m,突破压力大于5 MPa,突破半径介于10 ~ 20 nm,孔喉半径小于0.1 μm.塔中鹰山组内分布稳定、厚4~10m的高电阻含云灰岩构成的致密层段可作为局部封盖层,是中1井奥陶系鹰山组上油、下气油气分布的主要原因之一.%Mineral composition, micro-pore characteristics and well-logs from five wells were used to study the sealing capacity of the Ordovician carbonate rocks in Tazhong area,Tarim Basin. The Ordovician Lianglitage and Yingshan formations are at substage A-B of the middle diagenetic stage and substage A of the late diagenetic stage. For the Lianglitage Formation grainstone,the breakthrough pressure (BP) is 1. 81 -29. 76 Mpa,and the threshold radius (TR) is 13. 89 -77. 35 nm,. For the marlstones,the BP is 14. 33MPa and TR is 25. 9 -44. 51 nm. For the micritic limestone with band of argillite, the BP is 0. 98 - 10. 35 Mpa and the TR is 13. 52 - 142. 60 nm. The BP and the TR of the Yingshan Formation limy dolomites are 0. 98 - 10. 35 Mpa and 13. 52 - 142. 60 nm. Thus, the marlstone and partial grainstone of the Lianglitage Formation and the Yingshan Formation dolomite limestone have certain sealing capacity,with thickness over 5 m,BP over 5 Mpa,TR between 10-20 nm,pore throat radium

  18. Favorability for uranium in tertiary sedimentary rocks, southwestern Montana

    Energy Technology Data Exchange (ETDEWEB)

    Wopat, M A; Curry, W E; Robins, J W; Marjaniemi, D K

    1977-10-01

    Tertiary sedimentary rocks in the basins of southwestern Montana were studied to determine their favorability for potential uranium resources. Uranium in the Tertiary sedimentary rocks was probably derived from the Boulder batholith and from silicic volcanic material. The batholith contains numerous uranium occurrences and is the most favorable plutonic source for uranium in the study area. Subjective favorability categories of good, moderate, and poor, based on the number and type of favorable criteria present, were used to classify the rock sequences studied. Rocks judged to have good favorability for uranium deposits are (1) Eocene and Oligocene strata and undifferentiated Tertiary rocks in the western Three Forks basin and (2) Oligocene rocks in the Helena basin. Rocks having moderate favorability consist of (1) Eocene and Oligocene strata in the Jefferson River, Beaverhead River, and lower Ruby River basins, (2) Oligocene rocks in the Townsend and Clarkston basins, (3) Miocene and Pliocene rocks in the Upper Ruby River basin, and (4) all Tertiary sedimentary formations in the eastern Three Forks basin, and in the Grasshopper Creek, Horse Prairie, Medicine Lodge Creek, Big Sheep Creek, Deer Lodge, Big Hole River, and Bull Creek basins. The following have poor favorability: (1) the Beaverhead Conglomerate in the Red Rock and Centennial basins, (2) Eocene and Oligocene rocks in the Upper Ruby River basin, (3) Miocene and Pliocene rocks in the Townsend, Clarkston, Smith River, and Divide Creek basins, (4) Miocene through Pleistocene rocks in the Jefferson River, Beaverhead River, and Lower Ruby River basins, and (5) all Tertiary sedimentary rocks in the Boulder River, Sage Creek, Muddy Creek, Madison River, Flint Creek, Gold Creek, and Bitterroot basins.

  19. Thermal conditions of rock slopes below unstable infrastructure in Alpine permafrost area: the cases of the Cosmiques hut and the Grands Montets cable-car station (Mont Blanc massif)

    Science.gov (United States)

    Duvillard, Pierre-Allain; Magnin, Florence; Mörtl, Christian; Ravanel, Ludovic; Deline, Philip

    2017-04-01

    Thermal state of steep permafrost-affected rock faces is crucial to assess the safety and reliability of mountain infrastructure as current permafrost degradation affects the rock slope stability. In the Mont-Blanc massif, 23 infrastructures are built on such a rock face with 13 of them that are characterized by a high risk of destabilization (Duvillard et al., 2015), including the upper station of the Grands Montets cable car (3325 m a.s.l.) as well as the Cosmiques hut (3613 m a.s.l.) on which we will focus. These two buildings have already been affected by different geomorphological processes. A rockfall event (600 m3) occurred for example on the SE face on the Arête inférieure des Cosmiques on the 21st of August 1998 (Ravanel et al., 2013) and the Grands Montets case shows a slow subsidence of the stairway over the last decade. In order to better assess the role of the permafrost in these processes and to gain insight on possible future geomorphic activity, we characterized the current permafrost conditions and simulated its changes up to the end of the 21st century using two complementary approaches: (i) the result of ERT (Electrical Resistivity Tomography) surveys carried out in October 2016 on the northern and southern faces right below the Cosmiques hut (at the level of the foundations) and at the Aiguilles des Grands Montets; (ii) the modeling of mean annual rock surface temperature for 2016 and at the end of the 21st century (Magnin et al., in rev.). Duvillard P.-A., Ravanel L., Deline P. (2015). Risk assessment of infrastructure destabilisation due to global warming in the high French Alps. Journal of Alpine Research, 103 (2). Magnin F., Josnin J.-Y., Ravanel L., Pergaud J., Pohl B., Deline P. (in rev.). Modelling rock wall permafrost degradation in the Mont Blanc massif from the LIA to the end of the 21st century. The Cryosphere Discuss., doi:10.5194/tc-2016-132. Ravanel L., Deline P., Lambiel C. and Vincent C. (2013). Instability of a high alpine

  20. Scale dependence of rock friction at high work rate.

    Science.gov (United States)

    Yamashita, Futoshi; Fukuyama, Eiichi; Mizoguchi, Kazuo; Takizawa, Shigeru; Xu, Shiqing; Kawakata, Hironori

    2015-12-10

    Determination of the frictional properties of rocks is crucial for an understanding of earthquake mechanics, because most earthquakes are caused by frictional sliding along faults. Prior studies using rotary shear apparatus revealed a marked decrease in frictional strength, which can cause a large stress drop and strong shaking, with increasing slip rate and increasing work rate. (The mechanical work rate per unit area equals the product of the shear stress and the slip rate.) However, those important findings were obtained in experiments using rock specimens with dimensions of only several centimetres, which are much smaller than the dimensions of a natural fault (of the order of 1,000 metres). Here we use a large-scale biaxial friction apparatus with metre-sized rock specimens to investigate scale-dependent rock friction. The experiments show that rock friction in metre-sized rock specimens starts to decrease at a work rate that is one order of magnitude smaller than that in centimetre-sized rock specimens. Mechanical, visual and material observations suggest that slip-evolved stress heterogeneity on the fault accounts for the difference. On the basis of these observations, we propose that stress-concentrated areas exist in which frictional slip produces more wear materials (gouge) than in areas outside, resulting in further stress concentrations at these areas. Shear stress on the fault is primarily sustained by stress-concentrated areas that undergo a high work rate, so those areas should weaken rapidly and cause the macroscopic frictional strength to decrease abruptly. To verify this idea, we conducted numerical simulations assuming that local friction follows the frictional properties observed on centimetre-sized rock specimens. The simulations reproduced the macroscopic frictional properties observed on the metre-sized rock specimens. Given that localized stress concentrations commonly occur naturally, our results suggest that a natural fault may lose its

  1. Digital carbonate rock physics

    Science.gov (United States)

    Saenger, Erik H.; Vialle, Stephanie; Lebedev, Maxim; Uribe, David; Osorno, Maria; Duda, Mandy; Steeb, Holger

    2016-08-01

    Modern estimation of rock properties combines imaging with advanced numerical simulations, an approach known as digital rock physics (DRP). In this paper we suggest a specific segmentation procedure of X-ray micro-computed tomography data with two different resolutions in the µm range for two sets of carbonate rock samples. These carbonates were already characterized in detail in a previous laboratory study which we complement with nanoindentation experiments (for local elastic properties). In a first step a non-local mean filter is applied to the raw image data. We then apply different thresholds to identify pores and solid phases. Because of a non-neglectable amount of unresolved microporosity (micritic phase) we also define intermediate threshold values for distinct phases. Based on this segmentation we determine porosity-dependent values for effective P- and S-wave velocities as well as for the intrinsic permeability. For effective velocities we confirm an observed two-phase trend reported in another study using a different carbonate data set. As an upscaling approach we use this two-phase trend as an effective medium approach to estimate the porosity-dependent elastic properties of the micritic phase for the low-resolution images. The porosity measured in the laboratory is then used to predict the effective rock properties from the observed trends for a comparison with experimental data. The two-phase trend can be regarded as an upper bound for elastic properties; the use of the two-phase trend for low-resolution images led to a good estimate for a lower bound of effective elastic properties. Anisotropy is observed for some of the considered subvolumes, but seems to be insignificant for the analysed rocks at the DRP scale. Because of the complexity of carbonates we suggest using DRP as a complementary tool for rock characterization in addition to classical experimental methods.

  2. GRAPHITIZATION OF METASEDIMENTARY ROCKS IN THE WESTERN KONYA

    Directory of Open Access Journals (Sweden)

    Hüseyin KURT

    2000-01-01

    Full Text Available The Paleozoic-Mesozoic metasedimentary rocks in the study area are metacarbonate, metachert, metapelite, metasandstone and metaconglomerate. Graphite layers are 1cm to 2m thick, extend laterally for tens of meters and are intercalated with metasedimentary rocks. Generally, the graphite is black in color, with a well developed cleavage which is concordant with the cleavage of the host rocks. In addition, the crystal and flake graphites formed in metasedimentary rocks are mostly aligned parallel to the cleavage planes. These metamorphic rocks are subjected to shearing and granulation providing structural control for the development of graphite. It was probably this phenomenon that first led to emphasize the relationship between graphite and metasedimentary rocks. Graphite mineralization has been controlled by bedding, microfractures and granulations. Briefly, the metamorphism has converted carbonaceous matter into graphite .

  3. Session: Hard Rock Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Tennyson, George P. Jr.; Dunn, James C.; Drumheller, Douglas S.; Glowka, David A.; Lysne, Peter

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hard Rock Penetration - Summary'' by George P. Tennyson, Jr.; ''Overview - Hard Rock Penetration'' by James C. Dunn; ''An Overview of Acoustic Telemetry'' by Douglas S. Drumheller; ''Lost Circulation Technology Development Status'' by David A. Glowka; ''Downhole Memory-Logging Tools'' by Peter Lysne.

  4. Current results of an arachnological survey of some sandstone rock sites in Bohemia (so-called "rock cities"

    Directory of Open Access Journals (Sweden)

    Růžička, Vlastimil

    1992-07-01

    Full Text Available The spider fauna of the Adrspach-Teplice rockswas investigated. Some records on spider fauna of other nine sandstone rock areas are included. The phenomenon of "rock cities" manifests itself in three aspects: (1 In the bottom parts are microclimatically cold spaces, frequently hosting northern ot mountain species of invertebrates, which here have an azonal occurence. (2 the sun exposed tops of rocks can host thermophilous species. (3 Some species are limited to the surface of rocks and boulders. These are referred to as lithophilous or lithobiont species.

  5. Examining the relation between rock mass cuttability index and rock drilling properties

    Science.gov (United States)

    Yetkin, Mustafa E.; Özfırat, M. Kemal; Yenice, Hayati; Şimşir, Ferhan; Kahraman, Bayram

    2016-12-01

    Drilling rate is a substantial index value in drilling and excavation operations at mining. It is not only a help in determining physical and mechanical features of rocks, but also delivers strong estimations about instantaneous cutting rates. By this way, work durations to be finished on time, proper machine/equipment selection and efficient excavation works can be achieved. In this study, physical and mechanical properties of surrounding rocks and ore zones are determined by investigations carried out on specimens taken from an underground ore mine. Later, relationships among rock mass classifications, drillability rates, cuttability, and abrasivity have been investigated using multi regression analysis. As a result, equations having high regression rates have been found out among instantaneous cutting rates and geomechanical properties of rocks. Moreover, excavation machine selection for the study area has been made at the best possible interval.

  6. Geology of crystalline rocks of northern Fiordland: details of the granulite facies Western Fiordland Orthogneiss and associated rock units

    Science.gov (United States)

    Bradshaw, J.Y.

    1990-01-01

    A c. 700 km2 area of northern Fiordland (South Island, New Zealand) is described in which Early Cretaceous high-pressure metamorphic rocks and virtually unmetamorphosed plutonic rocks occur. The dominant rocks are orthogneisses developed from synmetamorphic basic-intermediate intrusive complexes, the youngest and most widespread of which is the Early Cretaceous Western Fiordland Orthogneiss (WFO). The latter has undergone granulite facies metamorphism and occurs throughout much of western Fiordland. WFO was emplaced synkinematically in a subduction-related magmatic arc. A collisional event during or immediately following magma emplacement resulted in crustal thickening equivalent to onloading of a 20 km thick section over rocks already buried at mid-crustal depths. This event was responsible for peak load pressures of c. 12-13 kbar. The steeply dipping Surprise Creek Fault juxtaposes high-pressure metamorphic rocks of western and central Fiordland against virtually unmetamorphosed gabbroic rocks of the Early Cretaceous Darran Complex. -from Author

  7. 喀斯特山区危岩崩塌形成机制研究——以三峡库区巫溪海螺湾危岩为例%Developing Mechanics for Perilous Rock in Karst Area:Taking the Hailuo Bay in the Three Gorges as an Example

    Institute of Scientific and Technical Information of China (English)

    邓珊珊; 陈洪凯; 游来凤

    2012-01-01

    研究三峡库区危岩崩塌地质灾害的演变机制和规律能帮助采取更合理的治理防护措施.采用地貌学和构造地质学等研究方法,对海螺湾危岩带的形成机制进行研究.据调查,该区的危岩单体和危岩群体均较发育,总面积达4.30×104 m2.根据其失稳模式可将该区的危岩主要分为压剪-滑动型和拉裂-倾倒型两种类型,所占比例分别为93.7%和6.3%.研究发现,海螺湾危岩崩塌的形成属于斜坡自我稳定的平衡发展过程.在河流的下切运动过程中,流水不停地淘蚀岸坡底部.长期的风化卸荷和岩溶作用,使坡体内部近于垂直的4组次生裂隙之间产生相互作用的,并且得到发展,最终贯穿,形成危岩体.研究认为,岩溶作用和大量的人类工程活动对灰岩地区危岩的形成和发展有一定影响.%Study the mechanisms and laws of evolution of the perilous rock collapse of geological disasters in Three Gorges Reservoir Area, is helpful for us to take a more rational management and protection measures, more effective ensure human lives and property safety. Study the formation mechanism of unstable rocks in Hailuo Bay with Geomorphology and structural geology. Both the monomer and the colony perilous rock are developing, and the area of perilous rock in a total with 4. 30× l04m2. According to the unstable modes, two types of perilous rock at the source of Hailuo Bay are classified as the compression and shear sliding type and the fracturing-toppling type, with the percentage of 93. 7% and 6, 3% respectively. The study found, the Hailuo Bay perilous rock collapse, belongs to the formation of self-stabilizing the balance of the development process. In the fluvial digesting movement, flowing dredging and erosion the bottom of the bank slope constantly* The weathering and the Karst never stop to develop the fissure, which the four main fractures interaction, until the penetrative cranny presence, and the perilous rocks

  8. Teaching the Rock Cycle with Ease.

    Science.gov (United States)

    Bereki, Debra

    2000-01-01

    Describes a hands-on lesson for teaching high school students the concept of the rock cycle using sedimentary, metamorphic, and igneous rocks. Students use a rock cycle diagram to identify pairs of rocks. From the rock cycle, students explain on paper how their first rock became the second rock and vice versa. (PVD)

  9. Umhlanga Rocks coastal defense

    NARCIS (Netherlands)

    De Jong, L.; De Jong, B.; Ivanova, M.; Gerritse, A.; Rietberg, D.; Dorrepaal, S.

    2014-01-01

    The eThekwini coastline is a vulnerable coastline subject to chronic erosion and damage due to sea level rise. In 2007 a severe storm caused major physical and economic damage along the coastline, proving the need for action. Umhlanga Rocks is a densely populated premium holiday destination on the

  10. Rock-hard coatings

    NARCIS (Netherlands)

    Muller, M.

    2007-01-01

    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has sign

  11. Slippery Rock University

    Science.gov (United States)

    Arnhold, Robert W.

    2008-01-01

    Slippery Rock University (SRU), located in western Pennsylvania, is one of 14 state-owned institutions of higher education in Pennsylvania. The university has a rich tradition of providing professional preparation programs in special education, therapeutic recreation, physical education, and physical therapy for individuals with disabilities.…

  12. Umhlanga Rocks coastal defense

    NARCIS (Netherlands)

    De Jong, L.; De Jong, B.; Ivanova, M.; Gerritse, A.; Rietberg, D.; Dorrepaal, S.

    2014-01-01

    The eThekwini coastline is a vulnerable coastline subject to chronic erosion and damage due to sea level rise. In 2007 a severe storm caused major physical and economic damage along the coastline, proving the need for action. Umhlanga Rocks is a densely populated premium holiday destination on the e

  13. Astronaut Neil Armstrong studies rock samples during geological field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, studies rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  14. Range sections as rock models for intensity rock scene segmentation

    CSIR Research Space (South Africa)

    Mkwelo, S

    2007-11-01

    Full Text Available This paper presents another approach to segmenting a scene of rocks on a conveyor belt for the purposes of measuring rock size. Rock size estimation instruments are used to monitor, optimize and control milling and crushing in the mining industry...

  15. A Study of the Rock Breaking Mechanism during Swirling Water Jet Drilling

    Institute of Scientific and Technical Information of China (English)

    NiHongjian; WangRuihe

    2004-01-01

    Based on an analysis of the factors affecting rock breaking and the coupling between rock and fluid during water jet drilling, the rock damage model and the damage-coupling model suitable for the whole rock breaking process under the water jet is established with continuous damage mechanics and micro-damage mechanics. The evolvement of rock damage during swirling water jet drilling is simulated on a nonlinear FEM and dynamic rock damage model, and a decoupled method is used to analyze the rock damage. The numerical results agree with the test results to a high degree, which shows the rock breaking ability of the swirling water jet is strong. This is because the jet particle velocity of the swirling water jet is three-dimensional, and its rock-breaking manner mainly has a slopping impact. Thus, the interference from returning fluid is less. All these aspects make it easy to draw and shear the rock surface. The rock breaking process is to break out an annular on the rock surface first, and then the annular develops quickly in both the radial and axial directions, the last part of the rock broken hole bottom is a protruding awl. The advantage of the swirling water jet breaking rock is the heavy breaking efficiency, large breaking area and less energy used to break rock per unite volume, so the swirling water jet can drill in a hole of a large diameter.

  16. 中国大陆干热岩地热资源潜力评估%Estimate of Geothermal Resources Potential for Hot Dry Rock in the Continental Area of China

    Institute of Scientific and Technical Information of China (English)

    汪集旸; 罗璐; 李卫卫; 胡圣标; 庞忠和; 何丽娟; 赵平; 朱传庆; 饶松; 唐晓音; 孔彦龙

    2012-01-01

    As one of the clean renewable energy, geothermal energy is very competitive. According to its genesis and exploration conditions, geothermal resources could be divided into two kinds, that is, one is hydrothermal resources and the other one is Hot Dry Rock (HDR) geothermal resources. Because of its universality and high temperature, HDR geothermal resources have great potential for projecting future development. The assessment of HDR geothermal resources potential is the base of HDR resources exploration. Here the heat flow map in the continental area of China is updated on the basis of more new heal flow data. Then the HDR geothermal resources are estimated using volume methods with a thermal physical access in the continental area of China (3 km -10 km). Results show that the total HDR geothermal energy is 20.9×10EJ, which is equivalent to standard coal of 714.9×l012t. If the recoverable energy is 2% by computing, then it is 168 times of conventional hydrothermal energy, and it is equivalent to 4,400 times of total annual energy consumption during the year of 2010 in China. Nevertheless, due to the limitation of economics and technology, the HDR geothermal resources exploration within the depth of 4-7km accompanied with an expected temperature of 150-250℃. should be conducted in the near future. Several target regions for HDR geolliermal resources exploration are proposed, including South Tibet, West Yunnan (Tengchong), the southeast coast of China (Zhejiang, Fujian and Guangdong), North China (BBB basin), the southeast regions of Ordos Basin (Fenwei Graben), and Northeast China (Songliao Basin). Finally, the future tasks involving geothermal resources research are listed.%地热资源是一种极具竞争力的清洁可再生能源,按其成因和产出条件可分为水热型和干热岩型,其中,干热岩型地热资源以其分布的普遍性和高热储温度而更具开发潜力与前景.干热岩地热资源潜力评估是干热岩开发的基础工

  17. PYRAMID ROADLESS AREA, CALIFORNIA.

    Science.gov (United States)

    Armstrong, Augustus K.; Scott, Douglas F.

    1984-01-01

    A geologic and mineral survey was conducted in the Pyramid Roadless Area, California. The area contains mineral showings, but no mineral-resource potential was identified during our studies. Three granodiorite samples on the west side of the roadless area contained weakly anomalous concentrations of uranium. Two samples of roof-pendant rocks, one metasedimentary rock and one metavolcanic rock, contain low concentrations of copper, and of copper and molybdenum, respectively. Although none was identified, the geologic terrane is permissive for mineral occurrences and large-scale, detailed geologic mapping of the areas of metasedimentary and metavolcanic roof pendants in the Pyramid Roadless Area could define a mineral-resource potential for tungsten and precious metals.

  18. Geochemical Characteristics of the Basic and Magnesian Metamorphic Rocks in Longyou Area,Zhejiang Province and Their Tectonic Setting%浙江龙游地区基性及镁质变质岩的地球化学特征及其构造环境

    Institute of Scientific and Technical Information of China (English)

    董学发; 唐增才; 陈忠大; 余盛强; 赵旭东; 周宗尧; 吴小勇; 肖庆辉

    2016-01-01

    位于扬子陆块东南缘与华夏地块之间的龙游地区出露一套中深变质岩系,其对华南前泥盆纪地质构造格局问题的解释至关重要,但目前人们对其形成时的大地构造背景了解不多。通过对其中的基性及镁质变质岩进行系统的岩石地球化学研究,可将这些岩石可以分为3种类型:“N-MORB”型、“T-MORB”型和“E-MORB”型。其中“N-MORB”型岩石原岩可能主要形成于洋内弧环境,“T-MORB”型岩石原岩主要形成于过渡型大洋中脊及火山弧环境,而“E-MORB”型岩石的原岩则主要形成于富集型大洋中脊、陆缘弧和板内环境。岩石成岩环境的多样性表明龙游地区的变质岩实属一套构造混杂岩,形成过程与古大洋地壳的俯冲、消减有关,这也为龙游榴闪岩的产出、定位提供了合理的解释。%A medium and high grade metamorphic rock series is exposed in Longyou area located in the southeast margin of Yan-gtze block and Cathaysia block,which is important for the interpretation of South China Predevonian tectonic pattern.But the tectonic setting of its formation remains unknown presently.It is found out these rocks can be divided into three types:“N-MORB”,“T-MORB”and “E-MORB”type rock by a basic and magnesian metamorphic rock geochemical study in this paper The protoliths of the “N-MORB”is mainly formed in the intra-oceanic arc,the “T-MORB”is mainly formed in the transition of mid-oceanic ridge and the volcanic arc,and the “E-MORB”type rock is formed in the enrichment of mid-oceanic ridge,epiconti-nental arc and intraplate environment.Rock diagenesis environment diversity shows that the metamorphic rock of Longyou area is a tectonic mélange and its forming process is related with the ancient oceanic crust subduction,which also provides a reasona-ble explanation for the output,positioning of the pomegranate amphibolite in Longyou area.

  19. Primary Analysis on Rock Salt Sedimentary Facies Area of Dawenkou Basin in Tai'an City%泰安市大汶口盆地岩盐沉积相区探析

    Institute of Scientific and Technical Information of China (English)

    张树淇; 郝瑞娥; 王浩

    2015-01-01

    Dongxiang depression Is a structural depression located in the west of Dawenkou basin.Favoura-ble structural conditions,ancient climate,geographical conditions,and the surrounding rich source formed rock salt deposit in the basin.Regional tectonic evolution caused sedimentary range and the concentration differences of brine.Thus,rock salt sedimentary facies have a certain evolution.The main tendency is a-long the direction of SWW from the northwest to the midwest of Dongxiang depression.The sedimentary thickness changes as well.%东向洼地是位于大汶口凹陷西部的构造洼地,有利的构造条件、古气候古地理条件、周边丰富的物源,形成了盆地内的岩盐矿床。区域构造演化,造成洼地内构造沉积幅度、卤水浓度差异,从而岩盐沉积相也有了一定的演化,主要趋势为沉积中心自沉积中心自东向洼地西北部沿走向 SWW 向向洼地中西部转移,沉积厚度也随之变化。

  20. Cuttability Assessment of Selected Rocks Through Different Brittleness Values

    Science.gov (United States)

    Dursun, Arif Emre; Gokay, M. Kemal

    2016-04-01

    Prediction of cuttability is a critical issue for successful execution of tunnel or mining excavation projects. Rock cuttability is also used to determine specific energy, which is defined as the work done by the cutting force to excavate a unit volume of yield. Specific energy is a meaningful inverse measure of cutting efficiency, since it simply states how much energy must be expended to excavate a unit volume of rock. Brittleness is a fundamental rock property and applied in drilling and rock excavation. Brittleness is one of the most crucial rock features for rock excavation. For this reason, determination of relations between cuttability and brittleness will help rock engineers. This study aims to estimate the specific energy from different brittleness values of rocks by means of simple and multiple regression analyses. In this study, rock cutting, rock property, and brittleness index tests were carried out on 24 different rock samples with different strength values, including marble, travertine, and tuff, collected from sites around Konya Province, Turkey. Four previously used brittleness concepts were evaluated in this study, denoted as B 1 (ratio of compressive to tensile strength), B 2 (ratio of the difference between compressive and tensile strength to the sum of compressive and tensile strength), B 3 (area under the stress-strain line in relation to compressive and tensile strength), and B 9 = S 20, the percentage of fines (University of Science and Technology (NTNU) model as well as B 9p (B 9 as predicted from uniaxial compressive, Brazilian tensile, and point load strengths of rocks using multiple regression analysis). The results suggest that the proposed simple regression-based prediction models including B 3, B 9, and B 9p outperform the other models including B 1 and B 2 and can be used for more accurate and reliable estimation of specific energy.

  1. Rock and mineral magnetism

    CERN Document Server

    O’Reilly, W

    1984-01-01

    The past two decades have witnessed a revolution in the earth sciences. The quantitative, instrument-based measurements and physical models of. geophysics, together with advances in technology, have radically transformed the way in which the Earth, and especially its crust, is described. The study of the magnetism of the rocks of the Earth's crust has played a major part in this transformation. Rocks, or more specifically their constituent magnetic minerals, can be regarded as a measuring instrument provided by nature, which can be employed in the service of the earth sciences. Thus magnetic minerals are a recording magnetometer; a goniometer or protractor, recording the directions of flows, fields and forces; a clock; a recording thermometer; a position recorder; astrain gauge; an instrument for geo­ logical surveying; a tracer in climatology and hydrology; a tool in petrology. No instrument is linear, or free from noise and systematic errors, and the performance of nature's instrument must be assessed and ...

  2. Pitted Rock Named Ender

    Science.gov (United States)

    1997-01-01

    This image was taken by the Sojourner rover's right front camera on Sol 33. The rock in the foreground, nicknamed 'Ender', is pitted and marked by a subtle horizontal texture. The bright material on the top of the rock is probably wind-deposited dust. The Pathfinder Lander is seen in the distance at right. The lander camera is the cylindrical object on top of the deployed mast.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and managed the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  3. Uranium in alkaline rocks

    Energy Technology Data Exchange (ETDEWEB)

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

    1978-04-01

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

  4. Alkaline Rocks and Geodynamics

    OpenAIRE

    BONIN, Bernard

    1998-01-01

    Origin of A-type alkali feldspar granites is currently the subject of a world-wide debate. Contrasting hypotheses have been proposed, which range from an entirely crustal origin to an almost complete mantle derivation. A-type alkali feldspar granites belong to either unimodal granite (rhyolite)-dominated association, or bimodal gabbro (basalt)-granite (rhyolite) suite. It is argued that (i) the ultimate mantle origin of basic to intermediate rocks is beyond doubt, (ii) highly evolved felsi...

  5. Investigation of the acid mine drainage potential of the Kopanang rock dump, Vaal Reefs / Charl Labuschagne

    OpenAIRE

    Labuschagne, Charl

    2008-01-01

    The Kopanang rock dump is one of several rock dumps in the Vaal Reefs gold mining area that may have an impact on the surface and groundwater quality. Few Acid Mine Drainage (AMD) studies exist on rock dumps in the South African gold industry due to the overwhelming acid generation from slime dams. Due to the existence of sulfide minerals in the Kopanang rock dump, there is a possibility that acid generation can occur, depending on the mineralogical composition of the ...

  6. Depositional Characteristics and Their Geological Implications of the Permo-Carboniferous Carbonate Rocks from Yingen-Ejinaqi and Their Surrounding Areas, Inner Mongolia, China%银根-额济纳旗及邻区石炭-二叠纪碳酸盐岩的沉积特征及其地质意义

    Institute of Scientific and Technical Information of China (English)

    赵省民; 陈登超; 邓坚; 李锦平

    2011-01-01

    火山岩或火山碎屑岩、辫状三角洲或扇三角洲砂砾岩,以及碳酸盐岩建造中的火山岩、火山碎屑岩和砂砾岩夹层,成为本区域石炭一二叠纪的潜在油气储层.%A study of depositional characteristics on carbonate rocks of Permo-Carboniferous was carried out by analyzing of petrology and their formation characteristics of carbonate rocks. A lot of fieldworks of the Permo-Carboniferous system in the study area indicate that, the carbonate rocks of Permo-Carboniferouus are dominated by calcirudite, crinoidal limestone and micrite with massive structure and graded bedding, volcanic or pyroclastic rocks acting as pedestals and interteds of the carbonate formations prevail in the area, which show the neritic paleoenvironmental settings of frequent tension-faulting, strong volcanisn, steep topography and deeper water during the period of Permo-Carboniferous. The Permo-Carboniferous carbonate rock formations respeetively on the pedestals of volcanic or pyroclastic rocks, granulites from braided river or fan deltas, mudstones originated from littoral zone and shelf comprise volcano-elevated carbonate rock formation (VEF). delta-elevated carbonate rock formation (DEF), coast-subsiding carbonate rock formation (CSF) and shelf-sboaling carbonate rock formation (SSF). The formations, all of which were formed by working together of region tectonics andchange in sea level, show the distinct mechanism of construction. Among of them, the voleano-elevated formation, with volcanic or py-roclastic interbeds and prevailling in the area, originated from the relative sea level fall driven by volcano eruption r~ulting from tectonicextension, in the setting of long-term ri~ in sea level The delta-elevated formation inferior to the volcano-elevated in development,with granulite interbeds, arose from the relative swa level fall driven by braided river or fan deltas progradation r~ulting from tectonicuplifting, in the context of long-term ri~ in sea

  7. Rock blasting and explosives engineering

    Energy Technology Data Exchange (ETDEWEB)

    Persson, P.-A.; Holmberg, R.; Lee, J. (New Mexico Institute of Mining and Technology, Socorro, NM (United States). Research Center for Energetic Materials)

    1994-01-01

    The book covers the practical engineering aspects of different kinds of rock blasting. It includes a thorough analysis of the cost of the entire process of tunneling by drilling and blasting compared with full-face boring. It covers the economics of the entire rock blasting operation and its dependence on the size of excavation. The book highlights the fundamentals of rock mechanics, shock waves and detonation, initiation and mechanics of rock motion. It describes the engineering design principles and computational techniques for many separate mining methods and rock blasting operations. 274 refs.

  8. Rock in Rio: forever young

    Directory of Open Access Journals (Sweden)

    Ricardo Ferreira Freitas

    2014-12-01

    Full Text Available The purpose of this article is to discuss the role of Rock in Rio: The Musical, as herald of megafestival Rock in Rio. Driven by the success that musicals have reached in Brazil, we believe that the design of this spectacle of music, dance and staging renews the brand of the rock festival, once it adds the force of young and healthy bodies to its concept. Moreover, the musical provides Rock in Rio with some distance from the controversal trilogy of sex, drugs and rock and roll, a strong mark of past festivals around the world. Thus, the musical expands the possibilities of growth for the brand.

  9. Rock in Rio: eternamente jovem

    OpenAIRE

    Ricardo Ferreira Freitas; Flávio Lins Rodrigues

    2014-01-01

    The purpose of this article is to discuss the role of Rock in Rio: The Musical, as herald of megafestival Rock in Rio. Driven by the success that musicals have reached in Brazil, we believe that the design of this spectacle of music, dance and staging renews the brand of the rock festival, once it adds the force of young and healthy bodies to its concept. Moreover, the musical provides Rock in Rio with some distance from the controversal trilogy of sex, drugs and rock and roll, a strong mark ...

  10. An Estimation Method of Stress in Soft Rock Based on In-situ Measured Stress in Hard Rock

    Institute of Scientific and Technical Information of China (English)

    LI Wen-ping; LI Xiao-qin; SUN Ru-hua

    2007-01-01

    The law of variation of deep rock stress in gravitational and tectonic stress fields is analyzed based on the Hoek-Brown strength criterion. In the gravitational stress field, the rocks in the shallow area are in an elastic state and the deep, relatively soft rock may be in a plastic state. However, in the tectonic stress field, the relatively soft rock in the shallow area is in a plastic state and the deep rock in an elastic state. A method is proposed to estimate stress values in coal and soft rock based on in-situ measurements of hard rock. Our estimation method relates to the type of stress field and stress state. The equations of rock stress in various stress states are presented for the elastic, plastic and critical states. The critical state is a special stress state, which indicates the conversion of the elastic to the plastic state in the gravitational stress field and the conversion of the plastic to the elastic state in the tectonic stress field. Two cases studies show that the estimation method is feasible.

  11. Petrotectonic assemblages and LA-ICP-MS zircon U-Pb age of Early Paleozoic volcanic rocks in Qimantag area, Tibetan Plateau%青藏高原祁漫塔格地区早古生代火山岩岩石构造组合和LA-ICP-MS锆石U-Pb年龄

    Institute of Scientific and Technical Information of China (English)

    王秉璋; 罗照华; 潘彤; 宋泰忠; 校培喜; 张志青

    2012-01-01

    A study of the Early Paleozoic volcanic rocks in Qimantag area reveals that they were formed in the Middle-Late Ordovi-cian period. The volcanic rocks can be assigned to four volcanic rock belts, i.e., Gonglugou - luanshigou belt, Kuangou - Xi-aolangyashan belt, Bayan Gol-Suhait belt and Naling Gol belt. The first volcanic rock belt belongs to a combination of Nb-enriched basalts characterized by high content of Nb (7.38×10-6-10.1×10-6), TiO2 (1.56%-2.24%) and P2O5 (0.24%-0.34%). The combinations of the volcanic rocks in the second belt are complicated, the SiO2 mass fractions of these rocks are concentrated on two end members, and these rocks can be further divided into two sub-combinations of basalt+basatic andesite and dacite+lithoidite. U-Pb LA-ICP-MS analyses of zircons in basalt and lithoidite yielded the data of 440.2±2.4Ma and 450.3±1.2Ma, respectively. The content of TiO2 (1.1%) and K2O(0.14%) is low while that of Na2O(2.17%) is high for the rocks of the tholeiite combinations in the third belt. Although the content of TiO2 (1.64%) is relatively high, the tholeiite combinations in the fourth belt are very similar to those in the third belt.%祁漫塔格地区早古生代海相火山岩发育,初步确定该地区早古生代海相火山岩的形成时代为中晚奥陶世,可划分出4个火山岩带,分别为公路沟-乱石沟带、宽沟-小狼牙山带、巴音郭勒-苏海图带和那陵格勒河带.公路沟-乱石沟带火山岩为富铌玄武岩组合,具有相对高的Nb(7.4×10-6~10.1×10-6)、TiO2( 1.56%~2.24%)和P2Os(0.24%~0.34%)含量.宽沟-小狼牙山带火山岩岩石类型复杂,SiO2质量分数集中分布于2个端元,可进一步分为玄武岩+玄武安山岩组合和英安岩+流纹岩组合,玄武岩中获得了440.2Ma±2.4Ma的LA-ICP-MS锆石U-Pb年龄值,流纹岩中获得了450.3Ma±1.2Ma的年龄值.巴音郭勒-苏海图带为拉斑玄武岩组合,具低钛(1.1%)、富钠(2.17%,)、低钾(0.14%)的特

  12. ROCK PHYSICS. Rock physics of fibrous rocks akin to Roman concrete explains uplifts at Campi Flegrei Caldera.

    Science.gov (United States)

    Vanorio, Tiziana; Kanitpanyacharoen, Waruntorn

    2015-08-07

    Uplifts in the Campi Flegrei caldera reach values unsurpassed anywhere in the world (~2 meters). Despite the marked deformation, the release of strain appears delayed. The rock physics analysis of well cores highlights the presence of two horizons, above and below the seismogenic area, underlying a coupled process. The basement is a calc-silicate rock housing hydrothermal decarbonation reactions, which provide lime-rich fluids. The caprock above the seismogenic area has a pozzolanic composition and a fibril-rich matrix that results from lime-pozzolanic reactions. These findings provide evidence for a natural process reflecting that characterizing the cementitious pastes in modern and Roman concrete. The formation of fibrous minerals by intertwining filaments confers shear and tensile strength to the caprock, contributing to its ductility and increased resistance to fracture.

  13. A revision of the Haiming rock avalanche (Eastern Alps)

    Science.gov (United States)

    Dufresne, Anja; Ostermann, Marc; Kelfoun, Karim; Ring, Max; Asam, Dario; Prager, Christoph

    2016-04-01

    The carbonate Haiming rock avalanche is directly neighbouring the larger Tschirgant rock avalanche deposit, both located in the upper Inn valley (Tyrol, Austria). Based on detailed morpho-lithologic mapping of the deposit, which has not been done at Haiming before, the sedimentology of the Holocene landslide debris is characterised. Structural-tectonic elements of the bedrock units at the scarp area are supplemented with borehole data from drillings at the source area giving valuable insights into the complex geological bedrock composition and structure. New source and runout reconstructions allow updated volumetric calculations, which are subsequently integrated into numerical runout modelling. Haiming is one of few topographically unobstructed rock avalanches, yet its morphology was greatly influenced by fluvial terraces, which are still discernible through the deposit on LiDAR hillshade images. We also address the influence of the rock avalanche on the valley floor and local river system as a short-lived dam and its interaction with fluvial incision. Finally, we discuss the Haiming rock avalanche in view of the other massive rock slope failures in the area ("Fernpass cluster"), their spatio-temporal distribution, and point out further highlights of this simple(?) rock avalanche deposit.

  14. Geochemical and tectonic uplift controls on rock nitrogen inputs across terrestrial ecosystems

    Science.gov (United States)

    Morford, Scott L.; Houlton, Benjamin Z.; Dahlgren, Randy A.

    2016-02-01

    Rock contains > 99% of Earth's reactive nitrogen (N), but questions remain over the direct importance of rock N weathering inputs to terrestrial biogeochemical cycling. Here we investigate the factors that regulate rock N abundance and develop a new model for quantifying rock N mobilization fluxes across desert to temperate rainforest ecosystems in California, USA. We analyzed the N content of 968 rock samples from 531 locations and compiled 178 cosmogenically derived denudation estimates from across the region to identify landscapes and ecosystems where rocks account for a significant fraction of terrestrial N inputs. Strong coherence between rock N content and geophysical factors, such as protolith, (i.e. parent rock), grain size, and thermal history, are observed. A spatial model that combines rock geochemistry with lithology and topography demonstrates that average rock N reservoirs range from 0.18 to 1.2 kg N m-3 (80 to 534 mg N kg-1) across the nine geomorphic provinces of California and estimates a rock N denudation flux of 20-92 Gg yr-1 across the entire study area (natural atmospheric inputs ~ 140 Gg yr-1). The model highlights regional differences in rock N mobilization and points to the Coast Ranges, Transverse Ranges, and the Klamath Mountains as regions where rock N could contribute meaningfully to ecosystem N cycling. Contrasting these data to global compilations suggests that our findings are broadly applicable beyond California and that the N abundance and variability in rock are well constrained across most of the Earth system.

  15. Petrología y geoquímica de las rocas máficas-ultramáficas del área río Las Águilas - arroyo de Los Manantiales, Provincia de San Luis Petrology and geochemistry of mafic-ultramafic rocks in the Las Águilas River-of the Manantiales stream area, San Luis

    Directory of Open Access Journals (Sweden)

    G. Ferracutti

    2007-09-01

    Full Text Available Dada la carencia de información de campo detallada, se efectuó el mapeo y muestreo de los cuerpos máficos-ultramáficos aflorantes entre el río de Las Águilas y el arroyo de Los Manantiales en la provincia de San Luis. La escasa información de campo, petrográfica y geoquímica de las unidades de éste área dificultaba la vinculación entre las rocas aflorantes y aquellas reconocidas en los testigos de perforación. Los cuerpos ígneos de interés se hallan en contacto con el basamento metamórfico a través de fallas de alto ángulo de buzamiento y/o contactos intrusivos. En Las Higueras y Virorco, se identificaron afloramientos de rocas máficas-ultramáficas con textura magmática primaria de tipo estratificada no-uniforme de regularidad intermitente. El estudio de estos cuerpos generó un desafío particular debido a los procesos deformación, metamorfismo y alteración que los han afectado. Estos factores no solo modificaron la mineralogía de las rocas sino que ademas generaron bloques basculados reconocidos por la presencia de texturas de estratificación magmaticas cuya posición espacial no se corresponde con la magmática originaria. Los patrones de los elementos de tierras raras normalizados a condrita permiten identificar un proceso de diferenciación, con mayor enriquecimiento en los contenidos de tierras raras en las rocas más evolucionadas. En base a los contenidos de tierras raras de las rocas ultramáficas, se infiere que la cristalización magmática estuvo controlada por la presencia de olivino y ortopiroxeno.Geological mapping was completed in the area between Las Águilas River and the Manantiales stream in San Luis province due to the absence of a detailed geologic map of the mafic-ultramafic bodies which occur in this region. Also the lack of petrographic and geochemical information constituted a draw back when attempting to relate surface and subsurface rocks. In this contribution a geological map of the area and

  16. Cause Analysis on the Phase Transition of the Tectonic Facies of the Metamorphic Rock Series in the Wutai Mountain-Heng Mountain Areas%五台山—恒山地区变质岩系构造相相变成因分析

    Institute of Scientific and Technical Information of China (English)

    郭景林; 米广尧; 范林森

    2011-01-01

    Areas in the Wutai mountain-Heng mountain are considered to be one of the most popular places for the tectonic facies researches owing to the various structural characters at different crust levels. In the present study, the structural characteristics of the Early Precambrian were analyzed. On the basis of the different geological characters of fold, fracture, pudding of the rock and syntectonic crystallization, some references were provided for analyzing the tectonic facies and the structural phase transition in the areas. Combined with the information of the geological characteristics, petrology, deformation,and metamorphic characteristics,and isotope chronology of the geological unit,the preliminary studies were conducted on the tectonic environment of the the Early Precambrian in the areas, and discussions were made on the crustal evolution andthe cause of the tectonic facies phase transition. The phenomena occurring commonly in the Metamorphic rock areas was explained reasonably,that is, the alienation between the same rocks and the convergence between the different rocks,or the same thing with different phases and the same phase with different faces. All of these provided the new research thinking and the working methods for the metamorphic rock areas.The high-grade regions of the Hornblende granulite phase in the Heng mountain areas represent the mid-lower crust's transitional zone and detachment zone. Their and it's typical structural styles, material composition, metamorphism and the effects of the deep melting have important significance on the researches of the mid-lower crust's rheological behavior, crustal differentiation and the cracking events for early continent.%五台山—恒山地区出露有不同层次的地壳,是研究构造相最理想的地区之一.作者对该区早前寒武纪构造特征进行了分析.根据不同层次的褶皱、断裂、布丁化岩石及同构造分泌结晶脉的宏观地质特征和与其相关的微组构特

  17. 印尼苏门答腊岛巴东地区埃达克质岩地球化学特征和构造环境%Geochemical characteristics and its significance of tectonic setting for Adakite-like rocks in Padang area, Sumatra (Indonesia)

    Institute of Scientific and Technical Information of China (English)

    朱章显; 杨振强; 胡鹏

    2015-01-01

    Based on composition of chemical analyses of rocks in Padong Area ,Sumatra (Indonesia) comparing with the data of the typical adakitic rocks ,this paper discusses the geochemical characteristics and their significance of tectonic setting .The comparative results shows that the trace element composition of the adakite-like rocks have the characteristics of low Sr contents (general 3 .88 × 10-6 ~83 .6 × 10-6 ) ,low Y contents(≤20 × 10-6 ) ,low Yb contents(≤1 .9 × 10-6 )of HREE ,and lower Sr/Y ratio (1 .09~18 .55) .On the chondrite-normalized spider diagram of trace element ,there are positive peak of Th ,Ba and strongly negative anomaly of Nb、Ta、Ti elements .The La/Yb ratio of REE are within the range of 1 .28~35 .46 ,and there are two types of chondrite-nomalized rare earth elements pattern:enriched and no enriched model , belonging to C-and O-type adakite respectively .The tectonic setting of theses adakite-like rocks are located at the volcano-arc of active continental margin near ocean-continent collision zone .The igneous magma derived from the areas of partly melting of seduction ocean slab plus partly molting and assimilation o f mantle wedge(MASH) .The distribution of adakite-like rocks in this area is in perfect accord with Cu-Au deposits of skarn type and iron deposits as well as hypothermal hot-spring Au zone .That meams the adakite-like rocks have a big significance in exploration .%根据苏门答腊岛巴东地区的岩石化学分析数据与典型埃达克岩进行对比,本文讨论其地球化学特征及其大地构造环境意义。对比结果表明:该地区的埃达克质岩微量元素特征为低Sr含量(一般为3.88×10-6~83.6×10-6),低重稀土元素Y含量(≤20×10-6)和低Yb含量(≤1.9×10-6),低Sr/Y比值(1.09~18.55)。在微量元素蛛网图上有 Th、Ba正异常峰和强烈的 Nb、Ta、Ti等元素负异常。稀土元素La/Yb比值为1.28~35.46,在REE元素

  18. El reconocimiento de avalanchas de rocas y deslizamientos de bloques rocosos prehistoricos en el área andina de Neuquén (37°15´ - 37°30´S Reconnaissance of prehistoric rock-avalanches and rock blocks slides in the Andean area of Neuquén (37°15´- 37°30´S

    Directory of Open Access Journals (Sweden)

    E.F. González Díaz

    2005-09-01

    pendientes, proceso que se interpreta promovido por un inductor sísmico, el que mostraría una relación adecuada con el marco sismotectónico y estructural de la región. Se destaca la influencia que pudo alcanzar la disposición periclinal de las acumulaciones volcánicas en el desprendimiento del flanco de una depresión caldérica. La consiguiente ameliorización climática postglaciaria, caracterizada por mayor humedad y precipitaciones, contribuyó a una disminución de la fricción y cohesión de los componentes de las pendientes. La edad de estos fenómenos no ha sido determinada, pero se la considerara posterior al englazamiento local cuaternario.Five prehistoric rock-avalanches are described in the northern cordilleran region of Neuquén Province, between 37º15' and 37º30'S and between 70º55' and 71º05'W. These slides and their deposits were not previously identified and moreover they were classified as glacial and glaciofluvial in origin. All of them are developed on volcanic-sedimentary deposits. They are named after local places: Cerro Piche Moncol, Cerro Guañaco, Cerro Coronal, Laguna Negra and Laguna Lauquen Mallín avalanches. The first three form a group of avalanches situated north of Reñileuvú creek, in the vicinity of the previously described Moncol rockavalanche. Their break-away zones are located on the lateral slopes of a pre-existing deep glacial valley. The biggest rock-avalanche is the Cerro Piche Moncol and its deposits are due to the collapse of the southern flank of a volcanic edifice with a small caldera. The Cerro Guañaco, Cerro Coronal and Laguna Negra rock-avalanches began as a slump slide to evolving distally into a flow. The slides of Laguna Lauquen Mallín are big rock-block slides. Some local factors, principally contrasting lithology and physical properties, structural factors and more humid conditions during postglacial times favourable conditions for the loss of slope equilibrium. The authors suggest that these gravitational

  19. Aespoe Hard Rock Laboratory Annual Report 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-08-01

    The Aespoe Hard Rock Laboratory has been constructed as part of the preparations for the deep geological repository for spent nuclear fuel in Sweden. The Tracer Retention Understanding Experiments are made to gain a better understanding of radionuclide retention in the rock and create confidence in the radionuclide transport models that are intended to be used in the licensing of a deep repository for spent fuel. The TRUE -1 experiment including tests with sorbing radioactive tracers in a single fracture over a distance of about 5 m has been completed. Diffusion and sorption in the rock matrix is the dominant retention mechanism over the time scales of the experiments. The main objective of the TRUE Block Scale Experiment is to increase understanding and our ability to predict tracer transport in a fracture network over spatial scales of 10 to 50 m. In total six boreholes have been drilled into the experimental volume located at the 450 m level. The Long-Term Diffusion Experiment is intended as a complement to the dynamic in-situ experiments and the laboratory experiments performed in the TRUE Programme. Diffusion from a fracture into the rock matrix will be studied in situ. The REX project focuses on the reduction of oxygen in a repository after closure due to reactions with rock minerals and microbial activity. Results show that oxygen is consumed within a few days both for the field and laboratory experiments. A new site for the CHEMLAB experiments was selected and prepared during 1999. All future experiment will be conducted in the J niche at 450 m depth. The Prototype Repository Test is focused on testing and demonstrating repository system function. A full-scale prototype including six deposition holes with canisters with electric heaters surrounded by highly compacted bentonite will be built and instrumented. Characterisation of the rock mass in the area of the Prototype repository is completed and the six deposition holes have been drilled. The Backfill and

  20. Evolution of Sedimentary Rocks

    Science.gov (United States)

    Veizer, J.; MacKenzie, F. T.

    2003-12-01

    For almost a century, it has been recognized that the present-day thickness and areal extent of Phanerozoic sedimentary strata increase progressively with decreasing geologic age. This pattern has been interpreted either as reflecting an increase in the rate of sedimentation toward the present (Barrell, 1917; Schuchert, 1931; Ronov, 1976) or as resulting from better preservation of the younger part of the geologic record ( Gilluly, 1949; Gregor, 1968; Garrels and Mackenzie, 1971a; Veizer and Jansen, 1979, 1985).Study of the rocks themselves led to similarly opposing conclusions. The observed secular (=age) variations in relative proportions of lithological types and in chemistry of sedimentary rocks (Daly, 1909; Vinogradov et al., 1952; Nanz, 1953; Engel, 1963; Strakhov, 1964, 1969; Ronov, 1964, 1982) were mostly given an evolutionary interpretation. An opposing, uniformitarian, approach was proposed by Garrels and Mackenzie (1971a). For most isotopes, the consensus favors deviations from the present-day steady state as the likely cause of secular trends.This chapter attempts to show that recycling and evolution are not opposing, but complementary, concepts. It will concentrate on the lithological and chemical attributes of sediments, but not deal with the evolution of sedimentary mineral deposits (Veizer et al., 1989) and of life ( Sepkoski, 1989), both well amenable to the outlined conceptual treatment. The chapter relies heavily on Veizer (1988a) for the sections dealing with general recycling concepts, on Veizer (2003) for the discussion of isotopic evolution of seawater, and on Morse and Mackenzie (1990) and Mackenzie and Morse (1992) for discussion of carbonate rock recycling and environmental attributes.

  1. Michael Learns to Rock

    Institute of Scientific and Technical Information of China (English)

    汪海涛

    2004-01-01

    夜幕降临.空气中传来北欧的声音,来自丹麦的四人流行乐队Michael Learns to Rock(迈克学摇滚)正把探情款款的歌声带到上海的咖啡厅和酒吧。北欧一直活跃着一批世界顶级的乐队.从丹麦的A-Ha到Aqua,从瑞典的ABBA到Roxette和Ace of Base,从挪威的Se

  2. Stress Intensity Factor Analysis and the Stability of Overhanging Rock

    Science.gov (United States)

    Huang, R. Q.; Wu, L. Z.; He, Q.; Li, J. H.

    2017-08-01

    The collapse of overhanging rock is a common geological hazard in mountainous areas. The stability of overhanging rock is usually determined by the growth of a crack along a main structural plane. On the basis of linear fracture mechanics combined with the stress concentration coefficient, an analytical method to determine the stress intensity factor (SIF) of overhanging rock is developed to evaluate its stability. Experiments on pre-cracked sandstone were carried out to simulate failure of overhanging rock and verify the analytical solution to fracturing and failure of overhanging rocks. Additionally, numerical solutions using the finite element method are derived to compare with the experimental results. The J-integral and displacement extrapolation methods are used to determine stress changes at the crack tip in the overhanging rocks, and the results confirm that the analytical solutions are consistent with the results of the numerical solutions, including the displacement extrapolation used to analyze the SIF of the overhanging rock. The ratio of fracture toughness to effective SIF at the crack tip can be considered useful when examining the stability of overhanging rock.

  3. Rock slope instabilities in Norway: First systematic hazard and risk classification of 22 unstable rock slopes

    Science.gov (United States)

    Böhme, Martina; Hermanns, Reginald L.; Oppikofer, Thierry; Penna, Ivanna

    2016-04-01

    average displacement rates of up to 6 cm are measured with differential GNSS and InSAR. Cosmogenic nuclide dating suggests an acceleration of the present displacement compared to the average displacement since the initiation of the gravitational movement approximately 7000 years ago. Furthermore, there exists a pre-historic rock avalanche 3 km north along the same slope. These characteristics result in a very high hazard for the Gamanjunni unstable rock slope. The consequence analyses focus on the possibility of life loss only. For this the number of persons in the area that can be affected by either the rock slope failure itself and/or its secondary consequence of a displacement wave in case that a rock slope failure would hit a water body is estimated. For Gamanjunni the direct consequences are approximately 40 casualties, representing medium consequences. A total of 48 scenarios were finally analyzed for hazard, consequences and risk. The results are plotted in a risk matrix with 5 hazard and 5 consequence classes, leading to 4 risk classes. One unstable rock slope was classified as very high hazard, 9 scenarios as high hazard, 25 as medium hazard and 13 as low hazard, while none were classified as very low hazard. The consequence analyses for those scenarios resulted in 5 scenarios with very high consequences (>1000 potential casualties), 13 scenarios with high consequences (100-1000 casualties), 9 scenarios with medium consequences (10-100 casualties), 6 scenarios with low consequences (1-10 casualties) and 15 scenarios with very low consequences (0-1 casualties). This resulted in a high risk for 6 scenarios, medium to high risk for 16 scenarios, medium risk for 7 scenarios and low risk for 19 scenarios. These results allow determining which unstable rock slopes do not require further follow-up and on which further investigations and/or mitigation measures should be considered.

  4. Rock critics as 'Mouldy Modernists'

    Directory of Open Access Journals (Sweden)

    Becky Shepherd

    2011-09-01

    Full Text Available Contemporary rock criticism appears to be firmly tied to the past. The specialist music press valorise rock music of the 1960s and 1970s, and new emerging artists are championed for their ‘retro’ sounding music by journalists who compare the sound of these new artists with those included in the established ‘canon’ of rock music. This article examines the narrative tropes of authenticity and nostalgia that frame the retrospective focus of this contemporary rock writing, and most significantly, the maintenance of the rock canon within contemporary popular culture. The article concludes by suggesting that while contemporary rock criticism is predominately characterised by nostalgia, this nostalgia is not simply a passive romanticism of the past. Rather, this nostalgia fuels a process of active recontextualisation within contemporary popular culture.

  5. Fossils, rocks, and time

    Science.gov (United States)

    Edwards, Lucy E.; Pojeta, John

    1999-01-01

    We study our Earth for many reasons: to find water to drink or oil to run our cars or coal to heat our homes, to know where to expect earthquakes or landslides or floods, and to try to understand our natural surroundings. Earth is constantly changing--nothing on its surface is truly permanent. Rocks that are now on top of a mountain may once have been at the bottom of the sea. Thus, to understand the world we live on, we must add the dimension of time. We must study Earth's history. When we talk about recorded history, time is measured in years, centuries, and tens of centuries. When we talk about Earth history, time is measured in millions and billions of years. Time is an everyday part of our lives. We keep track of time with a marvelous invention, the calendar, which is based on the movements of Earth in space. One spin of Earth on its axis is a day, and one trip around the Sun is a year. The modern calendar is a great achievement, developed over many thousands of years as theory and technology improved. People who study Earth's history also use a type of calendar, called the geologic time scale. It looks very different from the familiar calendar. In some ways, it is more like a book, and the rocks are its pages. Some of the pages are torn or missing, and the pages are not numbered, but geology gives us the tools to help us read this book.

  6. Rock Properties Model

    Energy Technology Data Exchange (ETDEWEB)

    C. Lum

    2004-09-16

    The purpose of this model report is to document the Rock Properties Model version 3.1 with regard to input data, model methods, assumptions, uncertainties and limitations of model results, and qualification status of the model. The report also documents the differences between the current and previous versions and validation of the model. The rock properties model provides mean matrix and lithophysae porosity, and the cross-correlated mean bulk density as direct input to the ''Saturated Zone Flow and Transport Model Abstraction'', MDL-NBS-HS-000021, REV 02 (BSC 2004 [DIRS 170042]). The constraints, caveats, and limitations associated with this model are discussed in Section 6.6 and 8.2. Model validation accomplished by corroboration with data not cited as direct input is discussed in Section 7. The revision of this model report was performed as part of activities being conducted under the ''Technical Work Plan for: The Integrated Site Model, Revision 05'' (BSC 2004 [DIRS 169635]). The purpose of this revision is to bring the report up to current procedural requirements and address the Regulatory Integration Team evaluation comments. The work plan describes the scope, objectives, tasks, methodology, and procedures for this process.

  7. A smart rock

    Science.gov (United States)

    Pressel, Phil

    2014-12-01

    This project was to design and build a protective weapon for a group of associations that believed in aliens and UFO's. They collected enough contributions from societies and individuals to be able to sponsor and totally fund the design, fabrication and testing of this equipment. The location of this facility is classified. It also eventually was redesigned by the Quartus Engineering Company for use at a major amusement park as a "shoot at targets facility." The challenge of this project was to design a "smart rock," namely an infrared bullet (the size of a gallon can of paint) that could be shot from the ground to intercept a UFO or any incoming suspicious item heading towards the earth. Some of the challenges to design this weapon were to feed cryogenic helium at 5 degrees Kelvin from an inair environment through a unique rotary coupling and air-vacuum seal while spinning the bullet at 1500 rpm and maintain its dynamic stability (wobble) about its spin axis to less than 10 micro-radians (2 arc seconds) while it operated in a vacuum. Precision optics monitored the dynamic motion of the "smart rock."

  8. Alpine glacial topography and the rate of rock column uplift

    DEFF Research Database (Denmark)

    Pedersen, Vivi Kathrine; Egholm, D.L.; Nielsen, S.B.

    2010-01-01

    The present study investigates the influence of alpine glacial erosion on the morphology and relief distribution of mountain regions associated with varying rock column uplift rates. We take a global approach and analyse the surface area distribution of all mountain regions affected by glacial....... On the basis of this decay, the analysed mountain regions fall within three distinct groupsprimarily reflecting variations in average values of rock columnuplift rates.Mountain ranges affected by rapid rock column uplift display high above-snowline relief and large decay lengths, whereas inactive orogens have...

  9. Selected elements of rock burst state assessment in case studies from the Silesian hard coal mines

    Institute of Scientific and Technical Information of China (English)

    KABIESZ Józef; MAKóWKA Janusz

    2009-01-01

    Exploitation of coal seams in the Upper Silesian Coal Basin is conducted in complex and difficult conditions. These difficulties are connected with the occurrence of many natural mining hazards and limitations resulting from the existing in this area surface infrastructure. One of the most important problems of Polish mining is the rock burst hazard and reliable evaluation of its condition. During long-years' mining practice in Poland a comprehensive system of evaluation and control of this hazard was de-veloped. In the paper the main aspects of rock burst hazard state evaluation will be presented, comprising: 1) rock mass inclination for rock bursts, I.e., rock strength properties investigation, comprehensive parametric evaluation of rock mass inclination for rock bursts, prognosis of seismic events induced by mining operations, methods of computer-aided modelling of stress and rock mass deformation parameters distribution, strategic rock mass classification under rock burst degrees; 2) immediate seismic and rock burst hazard state evaluation, I.e., low diameter test drilling method, seismologic and seismoacoustic method, comprehensive method of rock burst hazard state evaluation, non-standard methods of evaluation; 3) legal aspects of rock burst hazard state evaluation. Selected elements of the hazard state evaluation system are illustrated with specific practical examples of their applica-tion.

  10. Managing Rock Squirrels in Utah

    OpenAIRE

    Frey, Nicki

    2015-01-01

    Although they do not exist in large colonies like other ground squirrels, rock squirrels can still sometimes generate conflicts with homeowners and farmers alike. Most damage occurs when a few rock squirrels take residence in a homeowner’s back yard, and begin to forage on garden vegetables and fruit trees. There are several direct and indirect ways that private landowners can manage and reduce rock squirrels on their property. This fact sheet give management tips.

  11. [Hearing disorders and rock music].

    Science.gov (United States)

    Lindhardt, Bjarne Orskov

    2008-12-15

    Only few studies have investigated the frequency of hearing disorders in rock musicians. Performing rock music is apparently associated with a hearing loss in a fraction of musicians. Tinnitus and hyperacusis are more common among rock musicians than among the background population. It seems as if some sort of resistance against further hearing loss is developed over time. The use of ear protection devices have not been studied systematically but appears to be associated with diminished hearing loss.

  12. Towards a mechanical failure model for degrading permafrost rock slopes representing changes in rock toughness and infill

    Science.gov (United States)

    Mamot, Philipp; Krautblatter, Michael; Scandroglio, Riccardo

    2016-04-01

    The climate-induced degradation of permafrost in mountain areas can reduce the stability of rock slopes. An increasing number of rockfalls and rockslides originate from permafrost-affected rock faces. Discontinuity patterns and their geometrical and mechanical properties play a decisive role in controlling rock slope stability. Under thawing conditions the shear resistance of rock reduces due to lower friction along rock-rock contacts, decreasing fracture toughness of rock-ice contacts, diminishing fracture toughness of cohesive rock bridges and altered creep or fracture of the ice itself. Compressive strength is reduced by 20 to 50 % and tensile strength decreases by 15 to 70 % when intact saturated rock thaws (KRAUTBLATTER ET AL. 2013). Elevated water pressures in fractures can lead to reduced effective normal stresses and thus to lower shear strengths of fractures. However, the impact of degrading permafrost on the mechanical properties of intact or fractured rock still remains poorly understood. In this study, we develop a new approach for modeling the influence of degrading permafrost on the stability of high mountain rock slopes. Hereby, we focus on the effect of rock- and ice-mechanical changes along striking discontinuities onto the whole rock slope. We aim at contributing to a better rock-ice mechanical process understanding of degrading permafrost rocks. For parametrisation and subsequent calibration of our model, we chose a test site (2885 m a.s.l.) close by the Zugspitze summit in Germany. It reveals i) a potential rockslide at the south face involving 10E4m³ of rock and ii) permafrost occurrence due to ice-filled caves and fractures. Here we combine kinematic, geotechnical and thermal monitoring in the field with rock-mechanical laboratory tests and a 2D numerical failure modeling. Up to date, the following results underline the potential effects of thawing rock and fracture infill on the stability of steep rock slopes in theory and praxis: i. ERT and

  13. Rock avalanche and rock glacier: A compound landform study from Hornsund, Svalbard

    Science.gov (United States)

    Hartvich, Filip; Blahut, Jan; Stemberk, Josef

    2017-01-01

    On the northern coast of the Hornsund fjord at SW Svalbard, numerous rock block accumulations flank the foot of Rotjesfjellet ridge. Whereas these accumulations are widely described as rock glaciers, this study shows that other factors also influence formation of these landforms. In this study, morphometric profiling and terrain analyses, lichenometry, optical granulometry, Schmidt hammer measurements, geophysical measurements using electric resistivity tomography, geodetic measurements using terrestrial LiDAR and rockfall modelling were used to clarify the formation of one unusual block accumulation. The morphometric analysis of a detailed (0.5 m) DEM and relief profiles showed distinctly different morphology of one of four studied block accumulations. The electric resistivity tomography revealed an ice core in the accumulation, the Schmidt hammer sampling helped to establish relatively younger age of the lobe-like left part of accumulation and finally, the lichenometry was employed to place the event on the approximate position on the timescale. In conclusion, the unusual block accumulation is a result of two consequent processes: first, a typical foothill rock glacier has developed, and consequently a large rock avalanche occurred, adding material and deforming the NW part of the accumulation. Based on the results of lichenometry, the rock avalanche was estimated to be 250 ± 50 years old. The study thus presents one of the few reported slope deformation events from the recently deglaciated Arctic areas.

  14. Critical issues in soft rocks

    Institute of Scientific and Technical Information of China (English)

    Milton Assis Kanji

    2014-01-01

    This paper discusses several efforts made to study and investigate soft rocks, as well as their physico-mechanical characteristics recognized up to now, the problems in their sampling and testing, and the possibility of its reproduction through artificially made soft rocks. The problems in utilizing current and widespread classification systems to some types of weak rocks are also discussed, as well as other problems related to them. Some examples of engineering works in soft rock or in soft ground are added, with emphasis on their types of problems and solutions.

  15. Cataclastic rheology of carbonate rocks

    Institute of Scientific and Technical Information of China (English)

    LU Xiancai; SUN Yan; SHU Liangshu; GU Lianxing; GUO Jichun; ZHU Wenbin

    2005-01-01

    Based on the knowledge of the shallow-level mylonitization of detrital rocks and intrusive rocks, the poorly-known cataclastic rheology of carbonate rocks is discussed comprehensively in this paper. The cases taken from eastern China are analyzed in various aspects including ductile-brittle fault zone, rock texture and structure, clastomylonite layer, leucocratic stress minerals, and frictional dynamometamorphism. It is proposed that the cataclastic flow structure represented by clastomylonite texture is a cooling pattern of flow assemblage characterized by cooling metamorphism, cooling mylonite and cooling stress minerals. Such a pattern is formed generally in mildly reducing physicochemical environments, and is commonly related to regional tectonism and mesothermal and epithermal mineralization.

  16. Study on source rock potential and source rocks spatial distribution in the Manghan Faulted Sag, Kailu Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Manghan Faulted Sag is an exploratory target area in Kailu Basin. In order to determine its exploration prospect, the effectiveness of its source rocks is evaluated by organic geochemical behavior analysis of the samples, and their distributions are predicted using trace integration seismic inversion technology. Studies on their organic matter abundance, type and maturity indicate that the source rocks in the Sag have great generating potentials. Furthermore, it is found that, based on the spatial distribution predication, the source rocks in the Sag are well developed. Therefore, the Sag has a promising prospect for exploration.

  17. Rock.XML - Towards a library of rock physics models

    Science.gov (United States)

    Jensen, Erling Hugo; Hauge, Ragnar; Ulvmoen, Marit; Johansen, Tor Arne; Drottning, Åsmund

    2016-08-01

    Rock physics modelling provides tools for correlating physical properties of rocks and their constituents to the geophysical observations we measure on a larger scale. Many different theoretical and empirical models exist, to cover the range of different types of rocks. However, upon reviewing these, we see that they are all built around a few main concepts. Based on this observation, we propose a format for digitally storing the specifications for rock physics models which we have named Rock.XML. It does not only contain data about the various constituents, but also the theories and how they are used to combine these building blocks to make a representative model for a particular rock. The format is based on the Extensible Markup Language XML, making it flexible enough to handle complex models as well as scalable towards extending it with new theories and models. This technology has great advantages as far as documenting and exchanging models in an unambiguous way between people and between software. Rock.XML can become a platform for creating a library of rock physics models; making them more accessible to everyone.

  18. The discovery of Qushenla volcanic rocks in Tasepule area of Nyima Country, Tibet, and its geological significance%西藏尼玛县塔色普勒地区去申拉组火山岩的发现及其地质意义

    Institute of Scientific and Technical Information of China (English)

    吴浩; 李才; 胡培远; 范建军; 张红雨; 李娇

    2013-01-01

    对塔色普勒地区新发现的去申拉组火山岩进行了系统的地球化学和年龄研究.根据主量元素特征,将区内火山岩划分为富镁安山岩、英安岩和高分异流纹岩3种类型.富镁安山岩具有较高的MgO含量和Mg#值,是俯冲板片熔体与地幔楔相互作用的产物;英安岩与高分异流纹岩具有同源岩浆的特征,富集大离子亲石元素Rb、Th、U、K、Pb,亏损Nb、Ta、Ti、Sr等元素,并具有较高的Rb/Sr值,可能是地壳部分熔融经历了不同分异作用形成的.对流纹岩进行LA-ICP-MS锆石U-Pb定年,获得103Ma±1Ma和107Ma±1Ma的年龄值,显示区内去申拉组火山岩形成于早白垩世晚期.研究认为,区内去申拉组火山岩形成的地球动力学背景是早白垩世晚期班公湖-怒江洋壳向南俯冲过程中发生的板片断离,塔色普勒地区班公湖-怒江洋的陆-陆碰撞时间在107Ma左右.%This paper reports new whole-rock major and trace element data and zircon U-Pb dating results of the newly discovered Qushenla volcanic rocks in Tasepule area,Nyima County,Tibet.According to the features of major elements,the authors grouped volcanic rocks into three types,i.e.,magnesian andesites,dacite and highly differentiated rhyolite.The magnesian andesites produced by the interaction between the subducted slab melt and mantle wedge are rich in MgO and Mg#.Dacite and highly differentiated rhyolites are enriched in Rb,Th,U,K,Pb and depleted in Nb,Ta,Ti,and have high Rb/Sr ratios,which shows that they might be the product of partal melting of the crust which experienced different degrees of differentiation and evolution.The dating of zircons from two rhyolitic samples by LA-ICP-MS yielded ages of 103Ma±-1Ma and 107Ma±1Ma,which indicates that the Qushenla volcanic rocks in the study area were formed in late Early Cretaceous.It is considered that the plate fracturing that happened during the process of southward subduction of Bangong Co-Nujiang Ocean at

  19. Simulation of the water-rock reaction in Chaobai River ground-water storage area%潮白河地下水调蓄区水岩作用过程模拟

    Institute of Scientific and Technical Information of China (English)

    贾文飞; 杨洋; 赵阳; 李娟; 吕宁磬; 席北斗; 李鸣晓; 杨津津; 郭艳菲

    2016-01-01

    南水北调中线工程通水后,将有部分结余水量用于补给潮白河地下水调蓄区。由于南方地表水(以下简称南水)与北京当地地下水的水质存在一定差异,回灌过程中很有可能发生水岩相互作用。研究以潮白河地下水回灌区为例,通过静态摇瓶实验和水文地球化学模拟等研究方法,对南水补给北京深层地下水过程中产生的水岩作用过程和水质影响程度进行分析评价。研究结果表明:南水回灌过程中,地下水的主要离子成分会受到硝化作用、阳离子交换作用及包气带矿物质溶解等作用的综合影响。两种水混合过程中,土壤矿物相中的方解石和白云石不断溶解, Ca2+、Mg2+浓度逐渐升高,反应过程中还伴随强烈的阳离子交换作用,主要为 Na+与 Ca2+、Mg 2+的交换。南水比例越大,溶解氧促进硝化作用越明显;在硝化作用和碳酸平衡的共同影响下,地下水的 pH 值呈现先降低后升高的趋势。%In the process of The South-to-North Water Transfers, some of the water will be used to supplement the groundwater of Chaobai River basin. Due to the differences of Danjiangkou reservoir water and Beijing groundwater, water-rock interaction may occur. Taking the example of Chaobai River basin, we analyzed the water-rock interaction and changes of water during re-charge by batch experiments and hydrogeochemist ry simulation. The results showed that: during the recharge, the water was af-fected by nitrification, cat ion exchange and solution of minerals. With the increase of proport ion of southern water, calcite and dolomite dissolve and concentrations of calcium and magnesium were elevated coupled with cation exchange which mainly is so-dium with calcium and/ or magnesium. The higher proportion of south water, the stronger of nitrification is found. Affect ed by nitrif ication and carbonate balance, pH of groundwater was reduced at early stage then

  20. 四川安县地震灾区洪水沟泥石流特征及防治工程设计%FEATURES OF FLOOD-DITCH MUD-ROCK FLOW AND THE DESIGN OF PREVENTIVE AND TREATMENT WORKS IN THE EARTHQUAKE-HIT AREA OF AN COUNTY,SICHUAN

    Institute of Scientific and Technical Information of China (English)

    储长付; 胡凌

    2012-01-01

    四川"5.12"大地震,严重的破坏力当地的地质环境,诱发多处地质灾害。本文对地震灾区洪水沟泥石流形成机理、分布状况及性质特征进行了分析研究,实测和估算出固体物源动储量,详细计算了泥石流流体性质参数。进行了防治工程设计计算。结合工程实例及实践经验,提出了泥石流防治工程设计要点。%The Sichuan "5.12"great earthquake seriously damaged local geological environment and brought about many places of geological hazards.This paper analyzed formation mechanism,distribution,natures and features of flood-ditch mud-rock flows in the earthquake-hit areas,measured and estimated reserve of solid material source,made a calculation in detail of nature parameter of mud-rock flow,conducted design calculation for rpeventive and treatment works,and finally put forward the key points in design based on example works and experience.

  1. The relationship between geology and rock weathering on the rock instability along Mugling-Narayanghat road corridor, Central Nepal Himalaya

    OpenAIRE

    Regmi, Amar Deep; YOSHIDA, Kohki; Nagata, Hidehisa; Pradhan, Ananta Man Singh; Pradhan, Biswajeet; Pourghasemi, Hamid Reza

    2013-01-01

    The present study was conducted along the Mugling-Narayanghat road section and its surrounding region that is most affected by landslide and related mass-movement phenomena. The main rock types in the study area are limestone, dolomite, slate, phyllite, quartzite and amphibolites of Lesser Himalaya, sandstone, mudstone and conglomerates of Siwaliks and Holocene Deposits. Due to the important role of geology and rock weathering in the instabilities, an attempt has been made to understand the r...

  2. A Comparative Evaluation of Automatic Rock Detection Methods

    Science.gov (United States)

    Thompson, D. R.; Castano, R.

    2006-12-01

    Enabling rock detection allows rovers to make the most of each command cycle by performing autonomous site characterization, and prioritization of the most important data for downlink. On Earth these algorithms assist data analysis by automating laborious image annotation tasks. We compare the performance of several detection algorithms on a representative set of Mars Exploration Rover data. Tested algorithms include strategies based on pixel intensity (Castano et al., 2004), filter cascades (Viola et al., 2002), shading models (Gulick et al., 2001) and stereo range data (Gor et al., 2001). The test dataset consists of 13 navigation images and 104 panoramic camera images under various terrain and lighting conditions. Together these images contain over 50,000 manually-labeled rocks. We assess detectors' performance on autonomous geology tasks: identifying targets for spectroscopy, estimating the fractional area of terrain covered by rocks, and identifying the contour outlines of rocks above 4cm in length. While detection performance varied considerably across different detection strategies, images, and tasks, some general trends are apparent. All rock detection algorithms underestimated fractional coverage area to varying degrees. Accurate identification of contour outlines was especially difficult; most detectors exhibit low recall and various biases in rock shape and size. However, all detectors performed significantly better than random on the target selection task, paralleling recent successes in autonomous spectrometer targeting. Comparative evaluation on field-typical datasets will remain important as rock detection technologies continue to mature. References: Castano et al, Intensity-based Rock Detection for Acquiring Onboard Rover Science, LPSC 2004. Gor et al, Autonomous rock detection for Mars terrain, AIAA Space 2001. Gulick et al, Autonomous image analysis during the 1999 Marsokhod rover field test, JGR 2001. Viola et al, Robust Real-Time Object

  3. Rock the Globe

    CERN Multimedia

    Laëtitia Pedroso

    2010-01-01

    Created in 2005, the Swiss rock band "Wind of Change" is now candidate for the Eurovision Song Contest 2011 with a new song " Night & Light " with the music video filmed at CERN.   With over 20 gigs under their belt and two albums already released, the five members of the band (Alex Büchi, vocals; Arthur Spierer, drums; David Gantner, bass; Romain Mage and Yannick Gaudy, guitar) continue to excite audiences. For their latest composition "Night & Light", the group filmed their music video in the Globe of Science and Innovation. Winning the Eurovision contest would be a springboard in their artistic career for these young musicians. The selection results will be available December 11, 2010.      

  4. Electrochemistry of lunar rocks

    Science.gov (United States)

    Lindstrom, D. J.; Haskin, L. A.

    1979-01-01

    Electrolysis of silicate melts has been shown to be an effective means of producing metals from common silicate materials. No fluxing agents need be added to the melts. From solution in melts of diopside (CaMgSi2O6) composition, the elements Si, Ti, Ni, and Fe have been reduced to their metallic states. Platinum is a satisfactory anode material, but other cathode materials are needed. Electrolysis of compositional analogs of lunar rocks initially produces iron metal at the cathode and oxygen gas at the anode. Utilizing mainly heat and electricity which are readily available from sunlight, direct electrolysis is capable of producing useful metals from common feedstocks without the need for expendable chemicals. This simple process and the products obtained from it deserve further study for use in materials processing in space.

  5. Questa Baseline and Pre-mining Ground-Water Quality Investigation, 7. A Pictorial Record of Chemical Weathering, Erosional Processes, and Potential Debris-flow Hazards in Scar Areas Developed on Hydrothermally Altered Rocks

    Science.gov (United States)

    Plumlee, Geoffrey S.; Ludington, Steve; Vincent, Kirk R.; Verplanck, Philip L.; Caine, Jonathan S.; Livo, K. Eric

    2009-01-01

    Erosional scar areas developed along the lower Red River basin, New Mexico, reveal a complex natural history of mineralizing processes, rapid chemical weathering, and intense physical erosion during periodic outbursts of destructive, storm-induced runoff events. The scar areas are prominent erosional features with craggy headwalls and steep, denuded slopes. The largest scar areas, including, from east to west, Hottentot Creek, Straight Creek, Hansen Creek, Lower Hansen Creek, Sulfur Gulch, and Goat Hill Gulch, head along high east-west trending ridges that form the northern and southern boundaries of the lower Red River basin. Smaller, topographically lower scar areas are developed on ridge noses in the inner Red River valley. Several of the natural scar areas have been modified substantially as a result of large-scale open-pit and underground mining at the Questa Mine; for example, much of the Sulfur Gulch scar was removed by open pit mining, and several scars are now partially or completely covered by mine waste dumps.

  6. Placentation in the rock cavy, Kerodon rupestris (Wied)

    DEFF Research Database (Denmark)

    Oliveira, M.F.; Carter, Anthony M.; Bonatelli, M.

    2006-01-01

    Rock cavies are rodents found in the semi-arid caatinga of Brazil. We studied the structure of the rock cavy placenta by light and transmission electron microscopy. The exchange area of the labyrinth was organized in lobes separated by interlobular areas. The interhaemal barrier was syncytial...

  7. Failure mechanism of Mesozoic soft rock roadway in Shajihai coal mine and its surrounding rock control

    Institute of Scientific and Technical Information of China (English)

    Yuan Yue; Zhu Yongjian; Wang Weijun; Yu Weijian

    2014-01-01

    In view of the buckling failure caused by large deformation of Mesozoic soft rock roadway in Shajihai mining area, such as serious roof fall, rib spalling, floor heave, etc., based on the detail site investigation, theoretical analysis, mineral composition test, microstructure test, water-physical property test and field experiments were carried out. And we revealed the compound failure mechanism of Mesozoic soft rock roadway in Shajihai mining area, namely the molecule expansion-shear slip of weak structural plane-construction disturbance. On this basis, the coupling support technology whose core is constant resistance with large deformation bolt was proposed. The feature of this supporting technology is that a new type of structural composite material was used, which makes the supporting system not only has the ideal deformation characteristics, but also has high supporting resistance. Thus the fully release of plastic energy within surrounding rock and reasonable control of the thickness of the plastic ring were realized. Then the differential deformation between the surrounding rock and support was eliminated by the secondary coupling support of bolt–mesh–cable, and the bolt with high strength was applied in the base angle to control floor. Eventually the collaborative bearing system of surrounding rock–support was formed. Through field tests the validity and rationality of support was also verified.

  8. Aespoe Hard Rock Laboratory. Annual Report 2011

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-03-15

    The Aespoe Hard Rock Laboratory (HRL) is an important part of SKB's work with the design and construction of a deep geological repository for the final disposal of spent nuclear fuel. Aespoe HRL is located in the Simpevarp area in the municipality of Oskarshamn. One of the fundamental reasons behind SKB's decision to construct an underground laboratory was to create opportunities for research, development and demonstration in a realistic and undisturbed rock environment down to repository depth. The underground part of the laboratory consists of a tunnel from the Simpevarp peninsula to the southern part of Aespoe where the tunnel continues in a spiral down to a depth of 460 m. Aespoe HRL has been in operation since 1995 and considerable international interest has been shown in its research, as well as in the development and demonstration tasks. A summary of the work performed at Aespoe HRL during 2011 is given below.

  9. Aespoe hard rock laboratory. Annual report 2010

    Energy Technology Data Exchange (ETDEWEB)

    2011-02-15

    The Aespoe Hard Rock Laboratory (HRL) is an important part of SKB's work with the design and construction of a deep geological repository for the final disposal of spent nuclear fuel. Aespoe HRL is located in the Simpevarp area in the municipality of Oskarshamn. One of the fundamental reasons behind SKB's decision to construct an underground laboratory was to create opportunities for research, development and demonstration in a realistic and undisturbed rock environment down to repository depth. The underground part of the laboratory consists of a tunnel from the Simpevarp peninsula to the southern part of Aespoe where the tunnel continues in a spiral down to a depth of 460 m. Aespoe HRL has been in operation since 1995 and considerable international interest has been shown in its research, as well as in the development and demonstration tasks. A summary of the work performed at Aespoe HRL during 2010 is given below

  10. Workshop on hydrology of crystalline basement rocks

    Energy Technology Data Exchange (ETDEWEB)

    Davis, S.N. (comp.)

    1981-08-01

    This workshop covered the following subjects: measurements in relatively shallow boreholes; measurement and interpretation of data from deep boreholes; hydrologic properties of crystalline rocks as interpreted by geophysics and field geology; rock mechanics related to hydrology of crystalline rocks; the possible contributions of modeling to the understanding of the hydrology of crystalline rocks; and geochemical interpretations of the hydrology of crystalline rocks. (MHR)

  11. Rockin' around the Rock Cycle

    Science.gov (United States)

    Frack, Susan; Blanchard, Scott Alan

    2005-01-01

    In this activity students will simulate how sedimentary rocks can be changed into metamorphic rocks by intense pressure. The materials needed are two small pieces of white bread, one piece of wheat bread, and one piece of a dark bread (such as pumpernickel or dark rye) per student, two pieces of waxed paper, scissors, a ruler, and heavy books.…

  12. 汝阳地区熊耳群火山岩内夹层硅质岩的微区特征及地质意义%Micro-Area Characteristics of Laminated Chert in the Volcanic Rocks of Xionger Group of Ruyang Area and Its Geological Significances

    Institute of Scientific and Technical Information of China (English)

    罗安; 李红中; 赵明臻; 杨志军; 梁锦; 何俊国

    2014-01-01

    The Xionger Group was originated from the volcanic eruption and sedimentation in Precambrian ,whose sedimentary strata at the top were named Majiahe Formation .In the Majiahe Formation ,there were hydrothermal chert widely distributed , which were exhibited to be interlayers in the volcanic rocks .The polarized microscope ,X-ray diffraction (XRD) ,Raman and electron back scatter diffraction (EBSD) were conducted to study the characteristics in micro area of the jasperite samples ,which were from the sedimentary interlayers in the volcanic rocks of Majiahe Formation in Xionger Group .As shown in the micropho-tographs and EBSD images ,the quartz in the chert had small grain size ,low degree of crystallinity and close packed structure , which quite agreed with the characteristics of hydrothermal sedimentary chert .In the chert of Xionger Group ,there were clear banded (or lamellar) structures which were contributed by the diversities of the grain size and mineral composition .The different bands (or lamellars) had alternative appearance repeatedly ,and denoted the diversities and periodic changes in the substance sup-ply during the precipitation .According to the results of the XRD analysis ,the majority minerals of the chert was low tempera-ture quartz ,whose lattice parameters were a= b=0.491 3 nm ,c=0.540 5 nm and Z=3 .As denoted in the EBSD image and re-sult of Raman analysis ,several impurity minerals were formed in the chert in different stages ,whose geneses and formation time were quite different .The clay minerals and pyrite were scattered in distribution ,and should be contributed by the original sedi-mentation .On contrary ,the felsic minerals and mafic silicate minerals were originated from the sedimentation of tuffaceous sub-stance during the volcanic eruption .The minerals of volcanic genesis had relatively larger grain size ,and they deposited together with the hydrothermal sediments to form the bands (or lamellars) of coarse minerals .However ,the

  13. Rock suitability classification RSC 2012

    Energy Technology Data Exchange (ETDEWEB)

    McEwen, T. (ed.) [McEwen Consulting, Leicester (United Kingdom); Kapyaho, A. [Geological Survey of Finland, Espoo (Finland); Hella, P. [Saanio and Riekkola, Helsinki (Finland); Aro, S.; Kosunen, P.; Mattila, J.; Pere, T.

    2012-12-15

    This report presents Posiva's Rock Suitability Classification (RSC) system, developed for locating suitable rock volumes for repository design and construction. The RSC system comprises both the revised rock suitability criteria and the procedure for the suitability classification during the construction of the repository. The aim of the classification is to avoid such features of the host rock that may be detrimental to the favourable conditions within the repository, either initially or in the long term. This report also discusses the implications of applying the RSC system for the fulfilment of the regulatory requirements concerning the host rock as a natural barrier and the site's overall suitability for hosting a final repository of spent nuclear fuel.

  14. Plant and invertebrate assemblages on waste rock at Wangaloa coal mine, Otago, New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Rufaut, C.G.; Hammit, S.; Craw, D.; Clearwater, S.G. [University of Otago, Dunedin (New Zealand). Dept. of Geology

    2006-07-01

    Natural regeneration on waste rock was investigated at the old Wangaloa coal mine, south-east Otago. A 450-m long waste rock stack had been created 40-50 years ago, and has had little anthropogenic intervention since. The stack is made up of a gradient of three main waste rock types, defined as 'silt-rich', 'mixed', and I quartz-rich, which reflect different proportions of loess siltstone and quartz gravel conglomerate. Plant species assemblages were quantified in four 5-m{sup 2} quadrats in each waste rock type. Invertebrates were heat extracted from substrate cores (7 cm diameter; depth 5 cm) collected from quadrats over an eight-week period in spring 2003. Ordination analysis showed statistically distinct plant and invertebrate assemblages had arisen on each waste rock type. Revegetation patterns were dominated by native, woody individuals on all waste rock types, particularly manuka (Leptospermum scoparium) and kanuka (Kunzea ericoides). Plant cover on 'silt-rich' waste rock was four-fold that on 'quartz-rich' waste rock. Total numbers of invertebrates were highest on 'quartz-rich' waste rock, but richness greatest on 'silt-rich' waste rock. Collembola dominated the fauna but their numbers were proportionally greatest in poorly vegetated areas. Further work is required to explain the absence of plants and invertebrates from local areas of waste rock.

  15. Seismic properties of polyphase rocks

    Science.gov (United States)

    Wang, Qin

    2005-11-01

    Knowledge about the seismic properties of polyphase rocks is fundamental for interpreting seismic refraction and reflection data and for establishing lithospheric structure and composition models. This study aims to obtain more precise relationships between seismic properties of rocks and controlling factors (e.g., pressure, temperature, mineralogical and chemical compositions, microstructure of rocks), particularly for those rocks imprinted by ultrahigh-pressure (UHP) metamorphism. These relationships will be very helpful to extrapolate calculated and measured seismic properties of rocks to depths of interest and to engender interpretations relevant to petrological composition and tectonic process. An Internet Database of Rock Seismic Properties (DRSP) was set up and a Handbook of Seismic Properties of Minerals, Rocks and Ores was published. They comprise almost all data available in the literature during the past 4 decades and can serve as a convenient, comprehensive and concise information source on physical properties of rocks to the earth sciences and geotechnical communities. Statistical results of the DRSP reveal the dependence of seismic properties on density, porosity, humidity, and mineralogical and chemical compositions. Using 16 different averaging methods, we calculated P-wave velocities of 696 dry samples according to the volume fraction and elastic constants of each constituent mineral. Although only 22 common minerals were taken into account in the computation, the calculated P-wave velocities agree well with laboratory values measured at about 300 MPa, where most microcracks are closed and the mean Vp of a polymineralic rock is exclusively controlled by its modal composition. However, none of these mixture rules can simultaneously fit measured P-wave velocities for all lithologies or at all pressures. Therefore, more prudence is required in selecting an appropriate mixture rule for calculation of seismic velocities of different rock types.

  16. Research on Mechanism of Rock Burst Generation and Development for High Stress Rock Tunnels

    Institute of Scientific and Technical Information of China (English)

    高全臣; 赫建明; 王代华

    2001-01-01

    Through the investigation and analysis of high stress distribution in surrounding rock during the excavation of rock tunnels,the key factors to cause rock burst and the mechanism of rock burst generation and development are researched. The result shows that the scale and range of rock burst are related with elastic deformation energy storied in rock mass and the characteristics of unloading stress waves. The measures of preventing from rock burst for high stress rock tunnels are put forward.

  17. 花岗岩矿区水力岩土侵蚀研究初探--以福建省安溪县铁峰山花岗岩矿区为例%Initial Study on the Hydraulic Rock-soil Erosion in the Granite Mine Area-Taking the Tiefeng Mountain Granite Mine of Anxi County as the Example

    Institute of Scientific and Technical Information of China (English)

    林强

    2014-01-01

    以安溪县铁峰山花岗岩矿区为例,以集水区为单元,选取具有代表性的矿点作为研究对象,采用调查分析法、标桩法和侵蚀沟体积量算转换法进行矿区水力岩土侵蚀的研究。结果表明:①花岗岩矿区由于其自身的特点,水力岩土侵蚀以溅蚀、面蚀、沟蚀等形式体现,其土壤侵蚀强度多达到强烈甚至极强烈以上。②由于矿渣的阻滞作用,降雨后土壤多呈泥浆状溅散。雨滴的溅蚀使得土壤多呈现鳞片状侵蚀,降雨过后部分地表土层产生板结。③从研究区面蚀和沟蚀情况看,水力岩土侵蚀多达到极强烈以上侵蚀,且受坡长、坡度、堆体颗粒组成、有无植被覆盖、堆倒年限等因素的综合影响。%Taking the Tiefeng Mountain Granite Mine of Anxi County as the example , it was selected the representa-tive mine site for study based on the catchment as the unit .The study was conducted on the hydraulic rock -soil ero-sion in the mine area in accordance with the methods of investigation , standard stake and measurement conversion of e-rosion gully volume, respectively.The results showed that 1) because of own characteristics , hydraulic rock-soil ero-sion appeared in the forms of sputtering , sheet erosion and gully erosion with the erosion strength reached strong or ex-treme strong;2) due to the retardation of the slag , soil after raining sprayed as muddy .The sputtering erosion of the rain drop made the soil appeared the scaled erosion , that some top soil layers were hardened after raining;3) from the sheet erosion and gully erosion status in the study area , it was found that the hydraulic rock -soil erosion reached ex-treme strength and affected by the factors of the slope length and degree , the particle composition , vegetation cover and mound collapse years, etc.

  18. Tracer tomography (in) rocks!

    Science.gov (United States)

    Somogyvári, Márk; Jalali, Mohammadreza; Jimenez Parras, Santos; Bayer, Peter

    2016-04-01

    Physical behavior of fractured aquifers is rigorously controlled by the presence of interconnected conductive fractures, as they represent the main pathways for flow and transport. Ideally, they are simulated as a discrete fracture network (DFN) in a model to capture the role of fracture system geometry, i.e. fracture length, height, and width (aperture/transmissivity). Such network may be constrained by prior geological information or direct data resources such as field mapping, borehole logging and geophysics. With the many geometric features, however, calibration of a DFN to measured data is challenging. This is especially the case when spatial properties of a fracture network need to be calibrated to flow and transport data. One way to increase the insight in a fractured rock is by combining the information from multiple field tests. In this study, a tomographic configuration that combines multiple tracer tests is suggested. These tests are conducted from a borehole with different injection levels that act as sources. In a downgradient borehole, the tracer is recorded at different levels or receivers, in order to maximize insight in the spatial heterogeneity of the rock. As tracer here we chose heat, and temperature breakthrough curves are recorded. The recorded tracer data is inverted using a novel stochastic trans-dimensional Markov Chain Monte Carlo procedure. An initial DFN solution is generated and sequentially modified given available geological information, such as expected fracture density, orientation, length distribution, spacing and persistency. During this sequential modification, the DFN evolves in a trans-dimensional inversion space through adding and/or deleting fracture segments. This stochastic inversion algorithm requires a large number of thousands of model runs to converge, and thus using a fast and robust forward model is essential to keep the calculation efficient. To reach this goal, an upwind coupled finite difference method is employed

  19. Rock selection for nesting in Proformica longiseta Collingwood, 1978 (Hymenoptera, Formicidae) in a Mediterranean high mountain

    Science.gov (United States)

    Ignacio, Fernández Escudero; Tinaut, Alberto; Ruano, Francisca

    1993-06-01

    Proformica longiseta, an ant species endemic to certain high mountains, has been studied with regard to its tendency to nest underneath rocks. This behaviour led us to investigate whether a particular type of rock is selected, and, if so, the advantages to this species of the selection. This study was located at 2400 m above sea-level in the Sierra Nevada mountains (Granada, Spain). To determine the range of rock sizes available, in eight control plots the thicknesses were recorded and also the maximum and minimum diameters of all rocks with surface area of more than 6 cm2. A total of 1724 rocks were recorded, noting among the rock types available those that were used for nesting. Also as a preliminary estimate of the thermal characteristics of the rocks, we recorded the temperatures of the air, soil surface, soil under a rock covering an ant nest, and soil at 30 cm depth. The results indicate that P. longiseta selects flat rocks with a surface area/thickness ratio of 2 5, the thickness being not less than 1.5 cm, the surface area being 50 250 cm2 and volume less than 1000 cm3. This type of rock offers the nests two beneficial but apparently contradictory effects: (1) protection against high temperatures on hot days, and (2) warmth on colder days by absorbing the diffusing solar heat more effectively than the air or soil around the nest.

  20. Source rock evaluation of Cretaceous and Tertiary series in Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Oudin, J. (TOTAL-CFP, Pessac (France))

    1988-08-01

    Tunisia represents a mature hydrocarbon province with a long exploration history. In the Sfax-Kerkennah and Gabes Gulf areas, the hydrocarbon accumulations are located in series of Cretaceous and Tertiary age. To estimate the petroleum potential of this region, an evaluation of the source rock quality of the Cretaceous and Tertiary series was undertaken. In the Sfax-Kerkennak area, most of the wells studied indicate that, in the Tertiary, Ypresian and lower Lutetian show good organic content but, taking into account the potential productivity, only the Ypresian can be considered as a potential source rock. In the Cretaceous, mainly studies in the offshore area of the Gabes Gulf, the amount of organic matter is fair and it is chiefly located in Albian and Cenomanian. The Vraconian with its quite good potential is a valuable source rock. Due to the difference in the environment of deposition for these two possible source rocks - the Ypresian with its lagoon facies being carbonate and the Vraconian shaly - variations in the type of organic matter can be noted, although both are of marine origin. The hydrocarbons generated from these source rocks reflect these variations and permit them to correlate the different crude oils found in this area with their original source beds.

  1. Features of Minerogenic Series Related to Continental Volcanic Rocks in the Southeastern Coastal Area of China-A Case Study of the Daiyunshan-Shiniushan Volcanic Depression in Fujian

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The Daiyunshan-Shiniushan volcanic depression in Fujian Province is situated in a volcanic belt of the southeast coastal area in China along the west Pacific Ocean. A new breakthrough has been made in the exploration of gold and silver ore deposits in recent years. The minerogenic series of the Daiyunshan-Shiniushan volcanic depression is discussed in this paper based on the analysis of major metallogenic types and factors. According to the study of enormous ore deposits and occurrences in the study area, two minerogenic series have been recognized: 1. Late Jurassic Au-Ag-Pb-Zn minerogenic series related to intermediate-acid, acid volcanic formations; 2. nonmetallic minerogenic series (pyrophyllite, alunite pearlite, andalusite, zeolite, corundum and so on) related to intermediate and acid volcanic formations. The division and study of the minerogenic series have revealed metallogenic and time-space distribution characteristics of the ore deposits in the volcanic belt of the southeast coastal area in China , which are of economic importance for metallogenic prognosis .

  2. 78 FR 12365 - License Amendment Request for United Nuclear Corporation, Church Rock Mill-License No. SUA-1475

    Science.gov (United States)

    2013-02-22

    ... COMMISSION License Amendment Request for United Nuclear Corporation, Church Rock Mill--License No. SUA-1475... Materials License Number SUA-1475 for the UNC Church Rock Mill site located in New Mexico (the UNC license... flow model for the UNC Church Rock Mill site and adjacent downgradient areas . In a letter...

  3. Rock physics of fibrous rocks akin to Roman concrete explains uplifts at Campi Flegrei Caldera

    Science.gov (United States)

    Vanorio, Tiziana; Kanitpanyacharoen, Waruntorn

    2015-08-01

    Uplifts in the Campi Flegrei caldera reach values unsurpassed anywhere in the world (~2 meters). Despite the marked deformation, the release of strain appears delayed. The rock physics analysis of well cores highlights the presence of two horizons, above and below the seismogenic area, underlying a coupled process. The basement is a calc-silicate rock housing hydrothermal decarbonation reactions, which provide lime-rich fluids. The caprock above the seismogenic area has a pozzolanic composition and a fibril-rich matrix that results from lime-pozzolanic reactions. These findings provide evidence for a natural process reflecting that characterizing the cementitious pastes in modern and Roman concrete. The formation of fibrous minerals by intertwining filaments confers shear and tensile strength to the caprock, contributing to its ductility and increased resistance to fracture.

  4. Lidar-Based Rock-Fall Hazard Characterization of Cliffs

    Science.gov (United States)

    Collins, Brian; Greg M.Stock,

    2017-01-01

    Rock falls from cliffs and other steep slopes present numerous challenges for detailed geological characterization. In steep terrain, rock-fall source areas are both dangerous and difficult to access, severely limiting the ability to make detailed structural and volumetric measurements necessary for hazard assessment. Airborne and terrestrial lidar survey methods can provide high-resolution data needed for volumetric, structural, and deformation analyses of rock falls, potentially making these analyses straightforward and routine. However, specific methods to collect, process, and analyze lidar data of steep cliffs are needed to maximize analytical accuracy and efficiency. This paper presents observations showing how lidar data sets should be collected, filtered, registered, and georeferenced to tailor their use in rock fall characterization. Additional observations concerning surface model construction, volumetric calculations, and deformation analysis are also provided.

  5. 宜昌磷矿地质灾害现状及岩质边坡稳定性影响因素探讨%DISCUSSION ON GEOLOGICAL HAZARDS SITUATION AND EFFECT FACTORS OF ROCK SLOPE STABILITY OF YICHANG PHOSPHATE AREA

    Institute of Scientific and Technical Information of China (English)

    贺小黑; 逄思宇; 苏志军; 杜鹏; 王迎霜; 许多; 李英华

    2015-01-01

    通过对宜昌磷矿矿区内崩塌、滑坡、泥石流、地面塌陷、地裂缝等地质灾害等影响区内岩质边坡稳定性的因素的发育现状及现有防治的调查研究,并分析了地震、降雨、露天和地下开挖对边坡稳定性的影响.得出结论有:①崩塌及其隐患(危岩)是宜昌磷矿最主要的地质灾害,其次为地面塌陷和地裂缝,滑坡和泥石流较少.②地下采空区变形是引发地面塌陷和地裂缝的主要原因,也是引发崩塌危岩的重要原因;泥石流以沟谷型泥石流为主,采矿产生的固体废弃物可作为泥石流的物源,采空区回填、修建拦渣坝是预防其充当物源的主要措施.③影响岩质边坡稳定的因素包括地质因素、自然因素和人为因素等.④露天开挖时,在坡角不变时,稳定性系数随坡高的增大而减小;开挖高陡边坡所能形成的最大坡高约为460m.⑤当巷道位于边坡内部时,随着开挖范围的扩大,稳定性系数逐渐减小.%The occurrence situation as well as the present prevention and control measures of rock fall, landslide, debris flow, ground collapse and fracture at Yichang phosphate area is introduced. At the same time, the effect factors of rock slope stability with the effect of earthquake, rainfall, open-air and underground mining on slope stability are summarized. Some conclusion can be reached. Firstly, rock fall is the main geological hazard, secondly for ground collapse and fracture. Landslide and debris flow are less. Secondly, The mined-out area deformation is the important reason that rock fall, ground collapse and fracture are induced. The main type of debris flow is gully debris flow. Solid waste can become debris flow provenance, and backfilling mined-out area and building debris retaining dams are the main prevention measures. Thirdly, stability influence factors of rocky slope includes geological factor, natural factor and human factor. Fourthly, stability coefficient

  6. Rock salt constitutive modeling

    Energy Technology Data Exchange (ETDEWEB)

    Nickell, R.E.

    1980-03-18

    The Serata model is the best operational model available today because it incorporates: (1) a yield function to demarcate between viscoelastic and viscoplastic behavior of rock salt; (2) a pressure and temperature dependence for yield stresses; and (3) a standard linear solid, which can be readily extended into the non-linear regime, to represent creep behavior. Its only deficiencies appear to be the lack of secondary creep behavior (a free dashpot) and some unsettling arbitrariness about the Poisson's ratio (..nu.. ..-->.. 0.5) argument for viscoplasticity. The Sandia/WIPP model will have good primary and secondary creep capability, but lacks the viscoplastic behavior. In some cases, estimated inelastic strains may be underpredicted. If a creep acceleration mechanism associated with brine inclusions is observed, this model may require extensive revision. Most of the other models available (SAI, RE-SPEC, etc.) are only useful for short-term calculations, because they employ temporal power law (t/sup n/) primary creep representations. These models are unsatisfactory because they cannot represent dual mechanisms with differing characteristic times. An approach based upon combined creep and plasticity is recommended in order to remove the remaining deficiency in the Serata model. DOE/Sandia/WIPP should be encouraged to move aggressively in this regard.

  7. Uranium series, volcanic rocks

    Science.gov (United States)

    Vazquez, Jorge A.

    2014-01-01

    Application of U-series dating to volcanic rocks provides unique and valuable information about the absolute timing of crystallization and differentiation of magmas prior to eruption. The 238U–230Th and 230Th-226Ra methods are the most commonly employed for dating the crystallization of mafic to silicic magmas that erupt at volcanoes. Dates derived from the U–Th and Ra–Th methods reflect crystallization because diffusion of these elements at magmatic temperatures is sluggish (Cherniak 2010) and diffusive re-equilibration is insignificant over the timescales (less than or equal to 10^5 years) typically associated with pre-eruptive storage of nearly all magma compositions (Cooper and Reid 2008). Other dating methods based on elements that diffuse rapidly at magmatic temperatures, such as the 40Ar/39Ar and (U–Th)/He methods, yield dates for the cooling of magma at the time of eruption. Disequilibrium of some short-lived daughters of the uranium series such as 210Po may be fractionated by saturation of a volatile phase and can be employed to date magmatic gas loss that is synchronous with volcanic eruption (e.g., Rubin et al. 1994).

  8. They will rock you!

    CERN Multimedia

    Anaïs Schaeffer

    2013-01-01

    On 30 September, CERN will be the venue for one of the most prestigious events of the year: the concert for the Bosons&More event, the Organization’s celebration of the remarkable performance of the LHC and all its technical systems, as well as the recent fundamental discoveries. Topping the bill will be the Orchestre de la Suisse Romande, the CERN Choir, the Zürcher Sing-Akademie and the Alan Parsons Live Project rock group, who have joined forces to create an unforgettable evening’s entertainment.   The Orchestre de la Suisse Romande, directed by Maestro Neeme Järvi, artistic and musical director of the OSR. (Image: Grégory Maillot). >>> From the Orchestre de la Suisse Romande… Henk Swinnen, General Manager of the Orchestre de la Suisse Romande (OSR), answers some questions for the CERN Bulletin, just a few days before the event. How did this project come about? When CERN invited us to take part in the B...

  9. A quantitative analysis of rock cliff erosion environments

    Science.gov (United States)

    Lim, M.; Rosser, N.; Petley, D. N.; Norman, E. C.; Barlow, J.

    2009-12-01

    The spatial patterns and temporal sequencing of failures from coastal rock cliffs are complex and typically generate weak correlations with environmental variables such as tidal inundation, wave energy, wind and rain. Consequently, understanding of rock cliff behaviour, its response to predicted changes in environmental forcing and, more specifically, the interaction between marine and climatic factors in influencing failure processes has remained limited. This work presents the results from the first attempt to characterise and quantify the conditions on coastal cliffs that lead to accelerated rates of material detachment. The rate of change in an 80 m high section of coastal rock cliffs has been surveyed annually with high-resolution terrestrial laser scanning (TLS). The rockfall data have been analysed according to a simplified source geology that exhibit distinct magnitude-frequency distributions relating to the dominance of particular failure types. An integrated network of sensors and instrumentation designed to reflect the lithological control on failure has been installed to examine both the distinction between prevailing conditions and those affecting the local cliff environment and the physical response of different rock types to micro-climatic processes. The monitoring system records near-surface rock strain, temperature, moisture and micro-seismic displacement in addition to air temperature, humidity, radiation, precipitation, water-level and three-dimensional wind characteristics. A characteristic environmental signal, unique to the cliff face material, has been identified that differs substantially from that experienced by the surrounding area; suggesting that established methods of meteorological and tidal data collection are insufficient and inappropriate to represent erosive processes. The interaction between thermo- and hydro-dynamics of the cliff environment and the physical response of the rock highlights the composite environmental effects

  10. Multiverso: Rock'n'Astronomy

    Science.gov (United States)

    Caballero, J. A.

    2012-05-01

    In the last few years, there have been several projects involving astronomy and classical music. But have a rock band ever appeared at a science conference or an astronomer at a rock concert? We present a project, Multiverso, in which we mix rock and astronomy, together with poetry and video art (Caballero, 2010). The project started in late 2009 and has already reached tens of thousands people in Spain through the release of an album, several concert-talks, television, radio, newspapers and the internet.

  11. Geoelectrical Characterization of Sulphate Rocks

    OpenAIRE

    Guinea Maysounave, Ander

    2012-01-01

    [eng] Gypsum rocks are widely exploited in the world as industrial minerals. The purity of the gypsum rocks (percentage in gypsum mineral –CaSO4•2H2O- in the whole rock) is a critical factor to evaluate the potential exploitability of a gypsum deposit. It is considered than purities higher than 80% in gypsum are required to be economically profitable. Gypsum deposits have been studied with geoelectrical methods; a direct relationship between the electrical resistivity values of the gypsum roc...

  12. Aespoe Hard Rock Laboratory. Annual Report 2009

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    The Aespoe Hard Rock Laboratory (HRL) is an important part of SKB's work with the design and construction of a deep geological repository for the final disposal of spent nuclear fuel. Aespoe HRL is located in the Simpevarp area in the municipality of Oskarshamn. One of the fundamental reasons behind SKB's decision to construct an underground laboratory was to create opportunities for research, development and demonstration in a realistic and undisturbed rock environment down to repository depth. The underground part of the laboratory consists of a tunnel from the Simpevarp peninsula to the southern part of Aespoe where the tunnel continues in a spiral down to a depth of 460 m. Aespoe HRL has been in operation since 1995 and considerable international interest has been shown in its research, as well as in the development and demonstration tasks. A summary of the work performed at Aespoe HRL during 2009 is given below. Geoscience Geoscientific research is a basic activity at Aespoe HRL. The aim of the current studies is to develop geoscientific models of the Aespoe HRL and increase the understanding of the rock mass properties as well as knowledge of applicable methods of measurement. A main task within the geoscientific field is the development of the Aespoe Site Descriptive Model (SDM) integrating information from the different fields. The main activities in the geoscientific fields have been: (1) Geology evaluation of geological mapping techniques leading to the decision to develop a SKB mapping system and finalization of the mapping of rock surfaces in the new tunnel, (2) Hydrogeology monitoring and storage of data in the computerised Hydro Monitoring System, (3) Geochemistry sampling of groundwater in the yearly campaign and for specific experiments and (4) Rock Mechanics finalised the field tests on thermally-induced spalling in deposition holes and evaluated the effect of counterforce in the deposition holes. Natural barriers At Aespoe HRL

  13. Aespoe Hard Rock Laboratory. Annual Report 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    The Aespoe Hard Rock Laboratory (HRL) is an important part of SKB's work with the design and construction of a deep geological repository for the final disposal of spent nuclear fuel. Aespoe HRL is located in the Simpevarp area in the municipality of Oskarshamn. One of the fundamental reasons behind SKB's decision to construct an underground laboratory was to create opportunities for research, development and demonstration in a realistic and undisturbed rock environment down to repository depth. The underground part of the laboratory consists of a tunnel from the Simpevarp peninsula to the southern part of Aespoe where the tunnel continues in a spiral down to a depth of 460 m. Aespoe HRL has been in operation since 1995 and considerable international interest has been shown in its research, as well as in the development and demonstration tasks. The work performed at Aespoe HRL during 2006 is in this report described in six chapters: Geo-science - experiments, analysis and modelling to increase the knowledge of the surrounding rock; Natural barriers - experiments, analysis and modelling to increase the knowledge of the repository barriers under natural conditions; Engineered barriers - demonstration of technology for and function of important engineered parts of the repository barrier system; Aespoe facility - operation, maintenance, data management, monitoring, public relations etc; Environmental research; and finally, International co-operation.

  14. No Reprieve for Tasmanian Rock Art

    Directory of Open Access Journals (Sweden)

    Peter C. Sims

    2013-10-01

    Full Text Available The Australian State of Tasmania, at latitude 42 degrees south, became an island about 8,000 years ago when the sea rose to its present level, following the melting of polar and glacial ice that covered much of the land mass. After that time, the Tasmanian Aboriginal rock art developed independently of mainland Australia, with its form being basically linear with some naturalistic figures and a predominance of cupules. The petroglyphs with one lithophone site occur on various rock substrates varying in hardness from granite to sandstone. Many sites exist along the western coastline that borders the Southern Ocean where the landscape in some places has changed little since the arrival of Europeans in 1803. The significance of this Tasmanian Aboriginal cultural heritage along what is now known as the Tarkine Coast, named after an Aboriginal band that once inhabited this area, was recognised by the Australian Government in February 2013 when a 21,000 ha strip, 2 km wide, was inscribed on its National Heritage Register, being one of 98 special places listed in the country. However, politics and racism hamper its management. This paper is based on the results of 40 years of field recording of the Tasmanian Aboriginal rock art sites, many of which remain unpublished.

  15. Tectonic constraints on a deep-seated rock slide in weathered crystalline rocks

    Science.gov (United States)

    Borrelli, Luigi; Gullà, Giovanni

    2017-08-01

    Deep-seated rock slides (DSRSs), recognised as one of the most important mass wasting processes worldwide, involve large areas and cause several consequences in terms of environmental and economic damage; they result from a complex of controlling features and processes. DSRSs are common in Calabria (southern Italy) where the complex geo-structural setting plays a key role in controlling the geometry of the failure surface and its development. This paper describes an integrated multi-disciplinary approach to investigate a DSRS in Palaeozoic high-grade metamorphic rocks of the Sila Massif; it focuses on the definition of the internal structure and the predisposing factors of the Serra di Buda landslide near the town of Acri, which is a paradigm for numerous landslides in this area. An integrated interdisciplinary study based on geological, structural, and geomorphological investigations-including field observations of weathering grade of rocks, minero-petrographic characterisations, geotechnical investigations and, in particular, fifteen years of displacement monitoring-is presented. Stereoscopic analysis of aerial photographs and field observations indicate that the Serra di Buda landslide consists of two distinct compounded bodies: (i) an older and dormant body ( 7 ha) and (ii) a more recent and active body ( 13 ha) that overlies the previous one. The active landslide shows movement linked to a deep-seated translational rock slide (block slide); the velocity scale ranges from slow (1.6 m/year during paroxysmal stages) to extremely slow (responsible for the formation of this landslide. In particular, the landslide shows a strongly tectonic constraint: the flanks are bounded by high-angle faults, and the main basal failure surface developed inside an E-W southward-dipping thrust fault zone. The entire active rock mass (total volume of approximately 6 Mm3) slid at one time on a failure surface that dipped < 27°, and the maximum depth, as determined by inclinometer

  16. Statistically Based Inference of Physical Rock Properties of Main Rock Types in Germany

    Science.gov (United States)

    Koch, A.; Jorand, R.; Clauser, C.

    2009-12-01

    A major obstacle for an increased use of geothermal energy often lies in the high success risk for the development of geothermal reservoirs due to the unknown rock properties. In general, the ranges of thermal and hydraulic properties (thermal conductivity, volumetric heat capacity, porosity, permeability) in existing compilations of rock properties are too large to be useful to constrain properties for specific sites. Usually, conservative assumptions are made about these properties, resulting in greater drilling depth and increased exploration cost. In this study, data from direct measurements on more than 600 core samples from different borehole locations and depths enable to derive statistical moments of the desired properties for selected main rock types in the German subsurface. Using modern core scanning technology allowed measuring rapidly thermal conductivity, sonic velocity, and gamma density with high resolution on a large number of samples. In addition, we measured porosity, bulk density, and matrix density based on Archimedes’ principle and pycnometer analysis. Tests on a smaller collection of samples also include specific heat capacity, hydraulic permeability, and radiogenic heat production rate. In addition, we complemented the petrophysical measurements by quantitative mineralogical analysis. The results reveal that even for the same main rock type the results differ significantly depending on geologic age, origin, compaction, and mineralogical composition. For example, water saturated thermal conductivity of tight Palaeozoic sandstones from the Lower Rhine Embayment and the Ruhr Area is 4.0±0.7 W m-1 K-1 and 4.6±0.6 W m-1 K-1, respectively, which is nearly identical to values for the Lower Triassic Bunter sandstone in Southwest-Germany (high in quartz showing an average value of 4.3±0.4 W m-1 K-1). In contrast, saturated thermal conductivity of Upper Triassic sandstone in the same area is considerably lower at 2.5±0.1 W m-1 K-1 (Schilf

  17. Prediction on rock stratum stability using numerical simulation

    Institute of Scientific and Technical Information of China (English)

    刘少伟; 张永庆

    2003-01-01

    Numerical simulation, which is one of the important methods for tectonic simulation, can be successfully applied into the stability analysis of rock stratum in mining engineering. With numerical simulation, the characteristics of stress-deformation field of the area study can be well discovered, the stress concentration regions can be clearly located and the mechanism and effect of the stress concentration can be analyzed. The results of these studies offer fundamental data for evaluation of the rock stability and prediction of the tunnel wall stability in the working area.

  18. 准噶尔盆地中拐地区石炭—二叠纪火山岩特征及构造环境分析%Geochemical characteristics and tectonic setting of the Carboniferous-Permian volcanic rocks in Zhongguai area northwestern Junggar Basin

    Institute of Scientific and Technical Information of China (English)

    孙国强; 史基安; 张顺存; 陈吉; 贾艳艳

    2012-01-01

    中拐地区位于准噶尔盆地西北缘,是在石炭纪—早二叠世挤压应力场作用下形成的宽缓鼻状古隆起.石炭—二叠纪火山岩是主要的含油层系之一,到目前为止已发现了多个油气藏和出油气点,显示出良好的勘探前景.根据系统、精细的地震资料解释,中拐地区在石炭—二叠纪时期主要存在4期构造运动,分别对应4个不整合面:1)石炭系与二叠系之间;2)二叠系佳木河组与下乌尔禾组之间;3)二叠系下乌尔禾组与上乌尔禾组之间;4)二叠系上乌尔禾组与三叠系百口泉组之间.通过对中拐地区石炭—二叠纪火山岩的全岩元素分析表明,该区域主要为中-酸性的安山岩、英安岩和流纹岩及火山角砾岩和凝灰岩为主,其中SiO2的含量普遍较高,平均含量达到了67%,判定中拐地区的石炭—二叠纪火山岩喷发环境应位于岛弧体系的大陆内侧,在喷发过程中经历过陆壳的熔融作用.结合前人对周缘火山岩的研究,认为石炭—二叠纪时期中拐地区由岛弧环境逐渐进入陆内演化阶段,三叠纪开始进入稳定的沉积演化时期.%Zhong-Guai area is located in the Northwest margin of Junggar Basin, it is a broad nose palaeohigh formed in compressional stress field of Carboniferous Early Permain Period. Carboniferous-Permain volcanic rock is one of the mainly oil-bearing series, until now many hydrocarbon reservoirs and oil entry points are discovered, and showing good exploration prospects. According to systematic and elaborate seismic data interpretation, Zhong-Guai area have four tectonic movements in the Carboniferous-Permian period, corresponding to four unconformity respectively: 1 ) Between the Carboniferous and Permian system; 2) Between the Jiamuhe and Xiawuerhe Formation of Permian system; 3 ) Between the Xiawuerhe and Shangwuerhe Formation of Permian system; 4) Between the Xiawuerhe Formation of Permian system and Baikouquan Formation of

  19. BRIDGER WILDERNESS AND GREEN-SWEETWATER ROADLESS AREA, WYOMING.

    Science.gov (United States)

    Worl, Ronald G.; Ryan, George S.

    1984-01-01

    A mineral-resource appraisal of the Bridger Wilderness and contiguous Green-Sweetwater Roadless Area in Wyoming was made. This rugged and remote region is mostly Precambrian crystalline granitic rocks that contain only small and discontinuous areas of mineralization. The area is considered to have little promise for metallic mineral deposits. Sedimentary rocks in the area have minor coal seams and beds of phosphate rock, but the coal beds are thin and of limited extent, and the phosphate rock is low-grade compared to similar rocks elsewhere in the region. A probable potential for oil and gas at depth, assigned to part of the area, is based on the assumption that oil- and gas-bearing rocks exist at depth below a low-angle thrust fault and a wedge of Precambrian crystalline rock.

  20. FHL2 prevents cardiac hypertrophy in mice with cardiac-specific deletion of ROCK2.

    Science.gov (United States)

    Okamoto, Ryuji; Li, Yuxin; Noma, Kensuke; Hiroi, Yukio; Liu, Ping-Yen; Taniguchi, Masaya; Ito, Masaaki; Liao, James K

    2013-04-01

    The Rho-associated coiled-coil containing kinases, ROCK1 and ROCK2, are important regulators of cell shape, migration, and proliferation through effects on the actin cytoskeleton. However, it is not known whether ROCK2 plays an important role in the development of cardiac hypertrophy. To determine whether the loss of ROCK2 could prevent cardiac hypertrophy, cardiomyocyte-specific ROCK2-null (c-ROCK2(-/-)) were generated using conditional ROCK2(flox/flox) mice and α-myosin heavy-chain promoter-driven Cre recombinase transgenic mice. Cardiac hypertrophy was induced by Ang II infusion (400 ng/kg/min, 28 d) or transverse aortic constriction (TAC). Under basal conditions, hemodynamic parameters, cardiac anatomy, and function of c-ROCK2(-/-) mice were comparable to wild-type (WT) mice. However, following Ang II infusion or TAC, c-ROCK2(-/-) mice exhibited a substantially smaller increase in heart-to-body weight ratio, left ventricular mass, myocyte cross-sectional area, hypertrophy-related fetal gene expression, intraventricular fibrosis, cardiac apoptosis, and oxidative stress compared to control mice. Deletion of ROCK2 in cardiomyocytes leads to increased expression of four-and-a-half LIM-only protein-2 (FHL2) and FHL2-mediated inhibition of serum response factor (SRF) and extracellular signal-regulated mitogen-activated protein kinase (ERK). Knockdown of FHL2 expression in ROCK2-deficient cardiomyocytes or placing ROCK2-haploinsufficient (ROCK2(+/-)) mice on FHL2(+/-)-haploinsufficient background restored the hypertrophic response to Ang II. These results indicate that cardiomyocyte ROCK2 is essential for the development of cardiac hypertrophy and that up-regulation of FHL2 may contribute to the antihypertrophic phenotype that is observed in cardiac-specific ROCK2-deficient mice.

  1. Anthropic Rock: a brief history

    Directory of Open Access Journals (Sweden)

    R. B. Cathcart

    2011-03-01

    Full Text Available Stone tool-making is a reductive process. Synthetic rock manufacturing, preeminently an additive process, will not for-ever be confined to only the Earth-biosphere. This brief focuses on humanity's ancient past, hodiernal and possible future even more massive than present-day creation of artificial rocks within our exploitable Solar System. It is mostly Earth-centric account that expands the factual generalities underlying the unique non-copyrighted systemic technogenic rock classification first publicly presented (to the American Geological Society during 2001, by its sole intellectual innovator, James Ross Underwood, Jr. His pioneering, unique exposition of an organization of this ever-increasingly important aspect of the Anthropic Rock story, spatially expansive material lithification, here is given an amplified discussion for the broader geo and space science social group-purpose of encouragement of a completer 21st Century treatment of Underwood's explicative subject-chart (Fig. 2.

  2. Beach rock from Goa Coast

    Digital Repository Service at National Institute of Oceanography (India)

    Setty, M.G.A.P.; Wagle, B.G.

    temperature under the beach and inland. However, the thickness depends upon variabilities of precipitation, hinterland, water table fluctuations, temperature changes, composition and changes in sea level. Since the beach rock is formed in the tidal or spray...

  3. Rock mechanics stability at Olkiluoto, Haestholmen, Kivetty and Romuvaara

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, E.; Rautakorpi, J. [Saanio and Riekkola Oy, Helsinki (Finland)

    2000-02-01

    stresses are possibly sufficient to cause failure in the weaker types of rock. The risk of fracturing or spelling also increases once depths of 700 m are reached. Failures found at a deep level are, however, limited to small areas close to the excavated surfaces. The possibility of rock failure in the MLH concept only arose at greater depths than was the case with the KBS-3 concept. The results from the empirical methods and the numerical method were consistent. (orig.)

  4. Risk evaluation of rock burst through theory of static and dynamic stresses superposition

    Institute of Scientific and Technical Information of China (English)

    李振雷; 蔡武; 窦林名; 何江; 王桂峰; 丁言露

    2015-01-01

    Rock burst is one of the most catastrophic dynamic hazards in coal mining. A static and dynamic stresses superposition-based (SDSS-based) risk evaluation method of rock burst was proposed to pre-evaluate rock burst risk. Theoretical basis of this method is the stress criterion incurring rock burst and rock burst risk is evaluated according to the closeness degree of the total stress (due to the superposition of static stress in the coal and dynamic stress induced by tremors) with the critical stress. In addition, risk evaluation criterion of rock burst was established by defining the “Satisfaction Degree” of static stress. Furthermore, the method was used to pre-evaluate rock burst risk degree and prejudge endangered area of an insular longwall face in Nanshan Coal Mine in China. Results show that rock burst risk is moderate at advance extent of 97 m, strong at advance extent of 97−131 m, and extremely strong (i.e. inevitable to occur) when advance extent exceeds 131 m (mining is prohibited in this case). The section of two gateways whose floor abuts 15−3 coal seam is a susceptible area prone to rock burst. Evaluation results were further compared with rock bursts and tremors detected by microseismic monitoring. Comparison results indicate that evaluation results are consistent with microseismic monitoring, which proves the method’s feasibility.

  5. 西准噶尔马拉苏早泥盆世火山岩LA-ICP-MS锆石U-Pb年龄、地球化学特征及其大地构造意义%LA-ICP-MS zircon U-Pb geochronology, geochemical characteristics and tec-tonic significance of Early Devonian volcanic rocks in Malasu area, western Juggar Basin

    Institute of Scientific and Technical Information of China (English)

    翁凯; 徐学义; 马中平; 孙吉明; 张涛

    2015-01-01

    The early Devonian strata in Malasu area is a set of littoral-neritic facies volcanic sedimentary rocks. This paper reports the zircon age and geochemical characteristics of the volcanic rocks. A lot of Neo-Archean and middle Neo-Proterozoic zircons indicate that this area contains ancient continental crust material. According to the values of major elements (SiO 2 52.38%~69.6%, Na2O 2.80%~4.85%, K2O 0.16%~0.96%, TiO2 0.5%~1.96%, Al2O3 14.62%~18.18%, MgO 1.08%~5.75%) and the values of Mg# (22.92~38), the volcanic rocks of Malasu area are characterized by high content of sodium and low content of potassium, and thus belong to low-po⁃tassium tholeiite series and calc-alkaline series. The volcanic rocks have significant negative Eu anomalies ( 0.83~0.83), total rare earth element values of 73×10-6~115×10-6, and LREE/HREE values of 2.66~3.25. The geochemical characteristics of basaltic andesite sam⁃ples are similar to those of typical volcanic arc basalts, being rich in large ion lithophile elements K, Rb, Ba, Sr and depleted in the high field strength elements Nb, Ta, Zr, Hf. The same characteristics of enrichment of LILE and depletion of HFSE for dacite por⁃ phyry samples reflect the addition of lots of crust-derived materials. The chondrite-normalized REE and primitive mantle-normal⁃ized alteration-resistant trace element patterns for the dacite porphyry are similar to the patterns of basaltic andesite, which suggests that they belong to the comagmatic evolutionary series. Comprehensive research shows that the volcanic rocks have the characteristics of island arc volcanic rocks, and were formed in the volcanic island arc environment in the process of plate subduction.%马拉苏地区早泥盆世地层为一套滨海—浅海相火山—沉积岩系,对其中的火山岩夹层进行锆石U-Pb同位素定年和岩石地球化学研究,定年结果显示有大量的新太古代和中新元古代锆石,表明该区存在古老的大陆地壳

  6. SMART Boards Rock

    Science.gov (United States)

    Giles, Rebecca M.; Shaw, Edward L.

    2011-01-01

    SMART Board is a technology that combines the functionality of a whiteboard, computer, and projector into a single system. The interactive nature of the SMART Board offers many practical uses for providing an introduction to or review of material, while the large work area invites collaboration through social interaction and communication. As a…

  7. Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA

    Science.gov (United States)

    Wieczorek, G.F.; Stock, Gregory M.; Reichenbach, P.; Snyder, J.B.; Borchers, J.W.; Godt, J.W.

    2008-01-01

    Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m 3 of rock debris down a series of joint-controlled ledges to the floor of Yosemite Valley. The debris impacted talus near the base of Staircase Falls, producing fragments of flying rock that struck occupied cabins in Curry Village. Several years later on 9 June 2007, and again on 26 July 2007, smaller rock falls originated from the same source area. The 26 December 2003 event coincided with a severe winter storm and was likely triggered by precipitation and/or frost wedging, but the 9 June and 26 July 2007 events lack recognizable triggering mechanisms. We investigated the geologic and hydrologic factors contributing to the Staircase Falls rock falls, including bedrock lithology, weathering, joint spacing and orientations, and hydrologic processes affecting slope stability. We improved upon previous geomorphic assessment of rock-fall hazards, based on a shadow angle approach, by using STONE, a three-dimensional rock-fall simulation computer program. STONE produced simulated rock-fall runout patterns similar to the mapped extent of the 2003 and 2007 events, allowing us to simulate potential future rock falls from the Staircase Falls detachment area. Observations of recent rock falls, mapping of rock debris, and simulations of rock fall runouts beneath the Staircase Falls detachment area suggest that rock-fall hazard zones extend farther downslope than the extent previously defined by mapped surface talus deposits.

  8. Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA

    Directory of Open Access Journals (Sweden)

    G. F. Wieczorek

    2008-05-01

    Full Text Available Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m3 of rock debris down a series of joint-controlled ledges to the floor of Yosemite Valley. The debris impacted talus near the base of Staircase Falls, producing fragments of flying rock that struck occupied cabins in Curry Village. Several years later on 9 June 2007, and again on 26 July 2007, smaller rock falls originated from the same source area. The 26 December 2003 event coincided with a severe winter storm and was likely triggered by precipitation and/or frost wedging, but the 9 June and 26 July 2007 events lack recognizable triggering mechanisms. We investigated the geologic and hydrologic factors contributing to the Staircase Falls rock falls, including bedrock lithology, weathering, joint spacing and orientations, and hydrologic processes affecting slope stability. We improved upon previous geomorphic assessment of rock-fall hazards, based on a shadow angle approach, by using STONE, a three-dimensional rock-fall simulation computer program. STONE produced simulated rock-fall runout patterns similar to the mapped extent of the 2003 and 2007 events, allowing us to simulate potential future rock falls from the Staircase Falls detachment area. Observations of recent rock falls, mapping of rock debris, and simulations of rock fall runouts beneath the Staircase Falls detachment area suggest that rock-fall hazard zones extend farther downslope than the extent previously defined by mapped surface talus deposits.

  9. Spatial distribution of rock glaciers in the semi-arid Andes of Argentina

    Science.gov (United States)

    Blöthe, Jan Henrik; Halla, Christian; Schrott, Lothar; Götz, Joachim; Trombotto, Dario

    2016-04-01

    Active rock glaciers are indicators for permafrost in periglacial environments of high mountain areas. Within the permafrost body and the seasonally frozen active layer, these rock glaciers potentially store large amounts of water. Especially in semiarid mountain belts, such as the central Andes of Argentina, rock glaciers attain several kilometres in length, covering surface areas of >106 m2. Here, rock glaciers even outrange ice glaciers in cumulative area and absolute number, indicating they might constitute a large water reservoir in this semiarid part of the Andes. Despite their potential hydrological importance, our knowledge about the rock glaciers' spatial distribution, subsurface composition and absolute ice content is still very limited. Our study addresses this shortcoming and aims at assessing the hydrological significance of rock glacier permafrost in the semi-arid Andes of Argentina by combining local geophysical investigations with regional remote sensing analysis. Our research focuses on the central Andes between 30°S and 33°S, where we have compiled an inventory that comprises more than 1200 rock glaciers, as well as 154 clear-ice and debris-covered glaciers. Two field sites that bracket this regional study area towards their northern and southern edge have been selected for local geophysical investigations. At these locations, earlier studies detected the presence of rock glacier permafrost by thermal monitoring and geophysical prospection. Preliminary results of the regional spatial distribution indicate that the spatial density of rock glaciers increases towards the south, concomitant with a twofold increase in mean annual precipitation. Rock glacier density peaks in the area of the Aconcagua massif, while precipitation is further increasing towards the south. Simultaneously, the lower altitudinal limit of intact rock glaciers slightly decreases, with the lowest rock glacier toe positions in the northern study area located at ~3800 m a. s. l

  10. Study of the Interaction Model of PDC Cutters with Rock

    Directory of Open Access Journals (Sweden)

    Wang Jiajun

    2014-06-01

    Full Text Available The existing PDC cutters with rock interaction models does not match the actual drilling condition, because WOB can’t be loaded on their equipment, the influence of the cutting velocity on the force of cutters doesn’t be considered. A drilling experiment was carried out in the experimental device in which cutters can be loaded WOB. The relationship of cutting area, cutting speed, back dip angle of PDC cutter and rock performance with the force of PDC cutter were considered. The multiple nonlinear regression analysis were done on the basis of the experimental data, a new cutter-rock interaction model was established. The cutter area is the principal component influencing the force of cutters though the cluster analysis and principal component analysis. It is a logarithmic relationship between cutting velocity and the force of cutter, the theory of particle dynamics confirms this relationship.

  11. Rock and Soil Thermal Physical Properties in a Shallow Geothermal Energy Project Located in Zhengzhou Area%郑州市某浅层地热能勘查项目岩土热物性测试分析

    Institute of Scientific and Technical Information of China (English)

    孙君超; 黄峙; 胡平放; 雷飞; 朱娜; 邬田华

    2014-01-01

    The use of shallow geothermal energy is based on shallow geothermal energy exploration. The paper presents the application of thermal response test in the shallow geothermal energy project located in Zhengzhou area. The project is tested by a thermal response test rig with two different heat injection rates in two separated boreholes. The two-dimensional model inside borehole and the linear heat source model outside borehole are used as the heat transfer models. The thermal conductivity and heat capacity of soil is calculated by the two-variable parameter estimation (λs andρs cs ). The test results are analyzed.%浅层地热能勘察评价是浅层地热能开发利用的基础。介绍了岩土热物性测试仪的组成及工作原理,并将其应用于郑州市浅层地热能调查评价项目中进行岩土热物性测试现场热响应实验。本项目对郑州地区的两个测试孔分别进行不同加热功率条件下的现场热响应试验。传热模型采用钻孔内的二维模型及钻孔外的线热源模型,数据处理采用和双参数估计法,并利用Matlab软件最优化技术编程得到了岩土的综合导热系数和容积比热容,并对结果进行了分析和讨论。

  12. Prevention of sulfide oxidation in sulfide-rich waste rock

    Science.gov (United States)

    Nyström, Elsa; Alakangas, Lena

    2015-04-01

    The ability to reduce sulfide oxidation in waste rock after mine closure is a widely researched area, but to reduce and/or inhibit the oxidation during operation is less common. Sulfide-rich (ca 30 % sulfur) waste rock, partially oxidized, was leached during unsaturated laboratory condition. Trace elements such as As and Sb were relatively high in the waste rock while other sulfide-associated elements such as Cu, Pb and Zn were low compared to common sulfide-rich waste rock. Leaching of unsaturated waste rock lowered the pH, from around six down to two, resulting in continuously increasing element concentrations during the leaching period of 272 days. The concentrations of As (65 mg/L), Cu (6.9 mg/L), Sb (1.2 mg/L), Zn (149 mg/L) and S (43 g/L) were strongly elevated at the end of the leaching period. Different alkaline industrial residues such as slag, lime kiln dust and cement kiln dust were added as solid or as liquid to the waste rock in an attempt to inhibit sulfide oxidation through neo-formed phases on sulfide surfaces in order to decrease the mobility of metals and metalloids over longer time scale. This will result in a lower cost and efforts of measures after mine closure. Results from the experiments will be presented.

  13. Hydrologic properties of shale and related argillaceous rocks

    Energy Technology Data Exchange (ETDEWEB)

    Moiseyev, A.N.

    1979-11-15

    This report is the result of a bibliographic study designed primarily to collect hydrologic data on American clay-rich rocks. The following information was also sought: stratigraphy, environment of deposition, mineralogic composition, and diagenetic changes. The collected numerical data are presented in tables which contain densities, porosities, and/or hydraulic conductivities of approximately 360 samples. Additional data include hydraulic diffusivities, resistivities, flow rates, and rock strengths. Geologic information suggests that large deposits of shale which may be suited for waste repository belong to all ages and were formed in both marine and continental environments. Of the studied units, the most promising are Paleozoic in the eastern half of the country, Mesozoic in the central part, and Cenozoic in the Gulf Coast area and the West. Less widespread units locally present some additional possibilities. Mineralogic investigations suggest that the smectite content in rocks shows a decrease in time (70% in Recent rocks; 35% in pre-Mesozoic rocks). Because of this predominance of smectite in younger rocks, the modeling of repositories in post-Paleozoic formations might require knowledge of additional and poorly known parameters. Results of investigations into the mathematical relationships between porosity and permeability (or hydralic conductivity) suggest that in situ permeabilities could be estimated from sonic logs and fluid pressure changes at depth. 16 figures, 8 tables.

  14. Control of rock joint parameters on deformation of tunnel opening

    Institute of Scientific and Technical Information of China (English)

    Suman Panthee; P.K. Singh; Ashutosh Kainthola; T.N. Singh

    2016-01-01

    Tunneling in complex rock mass conditions is a challenging task, especially in the Himalayan terrain, where a number of unpredicted conditions are reported. Rock joint parameters such as persistence, spacing and shear strength are the factors which significantly modify the working environments in the vicinity of the openings. Therefore, a detailed tunnel stability assessment is critically important based on the field data collection on the excavated tunnel’s face. In this context, intact as well as rock mass strength and defor-mation modulus is obtained from laboratory tests for each rock type encountered in the study area. Finite element method (FEM) is used for stability analysis purpose by parametrically varying rock joint persis-tence, spacing and shear strength parameters, until the condition of overbreak is reached. Another case of marginally stable condition is also obtained based on the same parameters. The results show that stability of tunnels is highly influenced by these parameters and the size of overbreak is controlled by joint persistence and spacing. Garnetiferous schist and slate characterized using high persistence show the development of large plastic zones but small block size, depending upon joint spacing; whereas low persistence, low spacing and low shear strength in marble and quartzite create rock block fall condition.

  15. 30 CFR 57.3461 - Rock bursts.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Rock bursts. 57.3461 Section 57.3461 Mineral...-Underground Only § 57.3461 Rock bursts. (a) Operators of mines which have experienced a rock burst shall— (1) Within twenty four hours report to the nearest MSHA office each rock burst which: (i) Causes persons...

  16. 秦岭山阳水沟口组黑色岩系微量元素地球化学及其沉积成矿背景的指示意义%Trace element geochemical characteristics of the Shuigoukou Formation black rock series in Shanyang area of the Qinling Mountains and their indication significance for sedimentation-mineralization

    Institute of Scientific and Technical Information of China (English)

    王立社; 张复新; 侯俊富; 房波; 周燕

    2012-01-01

    According to field investigation, it is found that the black rock series of Shuigoukou Formation in Shanyang area of the Qinling Mountains is made up of micritic limestone,carbonaceous argillite, claystone, carbonaceous siliceous argillite, carbonaceous limestone and silicalite. Phosphatic nodule and barite are commonly seen in these rocks. The abundances of rare earth elements and some trace elements such as V,Ni,Co,U,Th in the black rock series were measured using ICP-MS method. Some conclusions have been reached; 1) The average concentrations of ore-forming elements (such as V,Mo,Ni,Ba,Pb,Zn,U,Ag,Cu,Cd,Tl,Bi and Cr) are several times to dozen times higher than their crustal abundances), showing that they are rich in the rock series, especially in silicolites and argilloid. Higher content of trace elements and rare earth elements is closely related to phosphorus,TOC and barium. 2)Different concentrations of rare earth elements are connected with different types of rock. The black rock series is usually of the LPvEE -enriched type. 3) The samples are characterized by slight or intermediate negative Ce anomalies (δ Ce =0.40~1.00) and distinct positive Eu anomalies, exclusively with high δ Eu (>2.1). 4)The ratios of U/Th display a large variation from 0.31 to 28.7, the ratios of w (V) /w (V +Ni) ( 0.51~1) and w (Ni) /w (Co) (4.8~49) are relatively high,the ratios of w (Ce) / w (La) (0.68~1.89) are normal, and the average rate of?w (Co) /w (Zn) is 0.21. According to a comparison of these related parameters of PvEE and trace elements with the available data in the references and the La/Yb- Ce/ La and La/Yb - PvEE diagrams, it is suggested that the black rock series of Shuigoukou Formation was formed in the environment of a dry, anoxic and profundal to semi-profundal faulted depression sea basin belonging to a passive continental margin, with the action of hydrothermal fluids.%通过野外调研发现,秦岭造山带山阳地区水沟口组黑色岩系主要由黑

  17. Seismic response of rock joints and jointed rock mass

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, A.; Hsiung, S.M.; Chowdhury, A.H. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    1996-06-01

    Long-term stability of emplacement drifts and potential near-field fluid flow resulting from coupled effects are among the concerns for safe disposal of high-level nuclear waste (HLW). A number of factors can induce drift instability or change the near-field flow patterns. Repetitive seismic loads from earthquakes and thermal loads generated by the decay of emplaced waste are two significant factors. One of two key technical uncertainties (KTU) that can potentially pose a high risk of noncompliance with the performance objectives of 10 CFR Part 60 is the prediction of thermal-mechanical (including repetitive seismic load) effects on stability of emplacement drifts and the engineered barrier system. The second KTU of concern is the prediction of thermal-mechanical-hydrological (including repetitive seismic load) effects on the host rock surrounding the engineered barrier system. The Rock Mechanics research project being conducted at the Center for Nuclear Waste Regulatory Analyses (CNWRA) is intended to address certain specific technical issues associated with these two KTUs. This research project has two major components: (i) seismic response of rock joints and a jointed rock mass and (ii) coupled thermal-mechanical-hydrological (TMH) response of a jointed rock mass surrounding the engineered barrier system (EBS). This final report summarizes the research activities concerned with the repetitive seismic load aspect of both these KTUs.

  18. Geochemistry and tectonic setting of Permian volcanic rocks in Yingen-Ejin Banner basin and its neighboring areas, western Inner Mongolia%内蒙古西部银根-额济纳旗盆地及邻区二叠纪火山岩的地球化学特征和构造环境

    Institute of Scientific and Technical Information of China (English)

    党犇; 赵虹; 林广春; 仵康林; 康晓燕; 葛海影; 吴斌; 刘少红

    2011-01-01

    Permian volcanic rocks are widespread in Yingen-Ejin Banner basin and its neighboring areas, and their genesis and tectonic setting remain a problem of much controversy. Based on a petrologic and geochemical analysis of Permian volcanic rocks in the study area, this paper attempts to clarify the palaeo-tectonic setting and provides independent evidence for understanding the nature of the basin. The volcanic rocks are dominated by basalts, basaltic-andesite and andesite, which fall into the sub-alkaline series. Mg# content of this suite ranges from 0.53 to 0.86, exhibiting strong depletion of the high field strength elements Nb, Ta and Ti and slight enrichment of LREE. In terms of REE, (La/Yb)N content ranges from 1.68 to 6.10, showing insignificant Eu depletion (δEu=0.64~0.99)and slightly right-oblique REE distribution patterns. These data show not only the characteristics of an intraplate setting on the whole but also the signature of a subduction zone. Combined with the sedmentary formation characteristics, the authors have reached the conclusion that the Permian magmatic activity of the study area was generated in an intraplate setting, with variable degrees of contamination of the crust during magmatic ascending, related probably to the mantle plume event.%银-额(银根-额济纳旗)盆地及其邻区二叠纪火山岩分布广泛,目前对其成因和构造背景研究还很薄弱.对该区火山岩岩石学和元素地球化学特征进行研究,为恢复二叠纪盆地性质与古构造环境提供了岩石地球化学约束.分析的二叠纪火山岩主要岩石类型为玄武岩、玄武安山岩和安山岩,显示亚碱性系列的特征.Mg#介于0.5~0.86之间,高场强元素Nb、Ta、Ti明显亏损,岩石轻度富集轻稀土元素(LREE),(La/Yb)N=1.68~6.10,Eu亏损不明显(δEu=0.64~0.99),稀土元素配分曲线右倾较缓.总体上既显示了板内构造环境的特征,又具有俯冲带地球化学的印记.综合沉积建造特征和

  19. 准噶尔盆地乌夏地区二叠系风城组云质岩类成因研究%Origin of Dolomitic Reservoir Rock in the Permian Fengcheng Formation in Wu-Xia Area of the Junggar Basin

    Institute of Scientific and Technical Information of China (English)

    朱世发; 朱筱敏; 陶文芳; 刘诗奇; 陈贺贺; 张越迁

    2013-01-01

    The dolomitic rocks of the Permian Fengcheng Formation are formed under special geologic conditions, and are important hydrocarbon reservoir rocks in Wu-Xia area in the Junggar Basin. Data of petrologic characteristics, SEM EDS and stable isotope composition indicate that dolomitizing host rocks are volcaniclassic rocks. Dolomitizing fluids probably came from brine from nearshore and shallow-water lake deposits in the Fengcheng Formation, which formed under arid climatic conditions, and from residual Mg-rich seawater from underlying Jiamuhe Formation and Carboniferous strata. Tuff has a significant content of plagioclase, in which anorthite and labradorite hydrolysis by CO2 can be couple with calcite precipitation. Later, Mg-rich brine percolate and replace calcite of the first stage to precipitate dolostones. The dolomitizing fluid has been driven by the thermal convection flow generated by volcanic eruption. At the same time, the overthrust of the Wu-Xia growth fault have speeded up the flow of deep Mg-rich water upwards, and induced the water to quickly penetrate and horizontally migrate in the strata. Fracture and fault play important role in controlling the formation of dolostone and the distribution of favorable reservoir.%  准噶尔盆地乌夏地区风城组发育的云质岩类是一套特殊成因的、重要的油气储层。岩石学、扫描电镜能谱和稳定同位素分析表明,发生白云岩化作用的母岩是火山凝灰物质,白云岩化的流体来自风城组干旱气候条件下形成的咸化滨浅湖卤水以及下伏佳木河组和石炭系残留的富镁海水。凝灰岩中富含大量的斜长石,其中的富钙长石在二氧化碳参与下水解蚀变,沉淀方解石(即方解石化)。后期富镁卤水渗滤早期形成的方解石,成岩交代形成白云岩。富镁流体运移受火山喷发产生的热流驱动,产生热对流环。同时,乌夏断裂同生逆掩活动加快深层

  20. Mars rover rock abrasion tool performance enhanced by ultrasonic technology.

    Science.gov (United States)

    Macartney, A.; Li, X.; Harkness, P.

    2016-12-01

    The Mars exploration Athena science goal is to explore areas where water may have been present on the early surface of Mars, and investigate the palaeo-environmental conditions of these areas in relation to the existence of life. The Rock Abrasion Tool (RAT) designed by Honeybee Robotics has been one of four key Athena science payload instruments mounted on the mechanical arm of the Spirit, Opportunity and Curiosity Mars Exploration Rovers. Exposed rock surfaces weather and chemically alter over time. Although such weathered rock can present geological interest in itself, there is a limit to what can be learned. If the geological history of a landing site is to be constructed, then it is important to analyse the unweathered rock interior as clearly as possible. The rock abrasion tool's role is to substitute for a geologist's hammer, removing the weathered and chemically altered outer surface of rocks in order to view the pristine interior. The RAT uses a diamond resin standard common grinding technique, producing a 5mm depth grind with a relatively high surface roughness, achieved over a number of hours per grind and consumes approximately 11 watts of energy. This study assesses the benefits of using ultrasonic assisted grinding to improve surface smoothness. A prototype Micro-Optic UltraSonic Exfoliator (MOUSE) is tested on a range of rock types and demonstrates a number of advantages over the RAT. In addition to a smoother grind finish, these advantages include a lower rate of tool tip wear when using a tungsten carbide tip as opposed to diamond resin, less moving parts, a grind speed of minutes instead of hours, and a power consumption of only 1-5 Watts.

  1. Aespoe Hard Rock Laboratory. Annual report 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    The Aespoe Hard Rock Laboratory has been constructed as part of the preparations for the deep geological repository for spent nuclear fuel in Sweden. The surface and borehole investigations and the research work performed in parallel with construction have provided a thorough test of methods for investigation and evaluation of bedrock conditions for construction of a deep repository. The Tracer Retention Understanding Experiments are made to gain a better understanding of radionuclide retention in the rock and create confidence in the radionuclide transport models that are intended to be used in the licensing of a deep repository for spent fuel. The experimental results of the first tracer test with sorbing radioactive tracers have been obtained. These tests have been subject to blind predictions by the Aespoe Task Force on groundwater flow and transports of solutes. The manufacturing of the CHEMLAB probe was completed during 1996, and the first experiments were started early in 1997. During 1997 three experiments on diffusion in bentonite using {sup 57}Co, {sup 114}Cs,{sup 85}Sr, {sup 99}Tc, and {sup 131}I were conducted. The Prototype Repository Test is focused on testing and demonstrating repository system function. A full scale prototype including six deposition holes with canisters with electric heaters surrounded by highly compacted bentonite will be built and instrumented. The characterization of the rock mass in the area of the prototype repository is in progress. The objectives of the Demonstration of Repository Technology are to develop, test, and demonstrate methodology and equipment for encapsulation and deposition of spent nuclear fuel. The demonstration of handling and deposition will be made in a new drift. The Backfill and Plug Test includes tests of backfill materials and emplacement methods and a test of a full scale plug. The backfill and rock will be instrumented with about 230 transducers for measuring the thermo-hydro-mechanical processes. The

  2. Diagenesis of clastic rock of Palaeozoic and its influence on reservoir in Tazhong area, Tarim basin%塔中地区古生界碎屑岩成岩作用及其对储层的影响

    Institute of Scientific and Technical Information of China (English)

    徐燕军; 于炳松; 钟大康

    2013-01-01

      通过取心井常规薄片、铸体薄片、扫描电镜、X 衍射等资料的分析,研究了塔里木盆地塔中地区古生界碎屑岩成岩作用及其对储层发育的影响。研究结果显示,研究区碎屑岩储层处于中成岩 A 期,且经历的主要成岩作用有压实与压溶作用、胶结作用、溶蚀作用、交代作用和重结晶作用等。另外,这些成岩作用对储集层孔隙发育及储层性质具有明显的影响:压实与压溶作用、交代、胶结作用、石英长石的次生加大以及重结晶作用使储层孔隙体积减小、物性变差,如压实与压溶作用使本区储层孔隙度损失14.1%~25.3%,交代、胶结作用使孔隙度损失13.9%;溶蚀作用是增加储集空间、改善储层物性最重要的成岩作用,如石英、长石及岩屑颗粒的溶蚀作用使储层产生次生孔隙,导致本区储层孔隙度平均增加6%~8%。%  Based on the full analysis of the data such as conventional section, cast section, X-ray diffraction and SEM, the Paleaozoic clastic diagenesis and its influence on clastic reservoir development in Tazhong area have been studied. The results of the study indicate that the clastic reservoir is in the stage A of middle diagenesis and the major diagenesis includes compaction, cementation(siliceous cementation, carbonate cementation and hydro-syalite cementation), dissolution(feldspar, minor debris and carbonate cement), alternation and fracture along with the sedimentary and diagenesis history. These diagenism has markedly influenced the pore development and physical properties of the reservoir. The mechanical compaction, the subsequent volcanism of quartz and feldspar has destructive influence on the physical properties of the reservoir. Compaction and pressure solution have in-duced the decrease in porosity(14.1%~25.3% ), the cement has filled up and blocked the pore throat of sandstone in various ways; Secondary overgrowth of quartz could

  3. Determining the stress of rock massif

    OpenAIRE

    2014-01-01

    Defining the stress rock massif is essential for design of underground facilities and methods of mining in the mines. Assessment the value of stress state of rock massif and rock strength in the various loads allows rational design. This is of particular importance when sizing columns, determining the extent of excavation, the cross-sections of underground rooms in problems with rock bursts and others. This paper briefly gives the basic methods of determining the rock massif stress as part of...

  4. Saharan Rock Art: Local Dynamics and Wider Perspectives

    Directory of Open Access Journals (Sweden)

    Marina Gallinaro

    2013-12-01

    Full Text Available Rock art is the best known evidence of the Saharan fragile heritage. Thousands of engraved and painted artworks dot boulders and cliffs in open-air sites, as well as the rock walls of rockshelters and caves located in the main massifs. Since its pioneering discovery in the late 19th century, rock art captured the imagination of travellers and scholars, representing for a long time the main aim of research in the area. Chronology, meaning and connections between the different recognized artistic provinces are still to be fully understood. The central massifs, and in particular the "cultural province" encompassing Tadrart Acacus and Tassili n’Ajer, played and still play a key role in this scenario. Recent analytical and contextual analyses of rock art contexts seem to open new perspectives. Tadrart Acacus, for the richness and variability of artworks, for the huge archaeological data known, and for its proximity to other important areas with rock art (Tassili n’Ajjer, Algerian Tadrart and Messak massifs is an ideal context to analyze the artworks in their environmental and social-cultural context, and to define connections between cultural local dynamics and wider regional perspectives.

  5. The oldest rock of Ivory Coast

    Science.gov (United States)

    Kouamelan, Alain Nicaise; Djro, Sagbrou Chérubin; Allialy, Marc Ephrem; Paquette, Jean-Louis; Peucat, Jean-Jacques

    2015-03-01

    The tonalitic gneiss of Balmer (TGB), in the SASCA area of south-western Ivory Coast, previously dated at 3141 ± 2 Ma using the single zircon evaporation method, is regarded as a relic of Archean rock within the Paleoproterozoic (Birimian) formation of the West African Craton (WAC). We present new geochronological data for the TGB using the laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method. We obtain a U-Pb age of 3207 ± 7 Ma for abundant zircons extracted from the tonalitic gneiss, and interpret this age as that of the magmatic protolith because of the igneous-type homogeneous zircon population. Certain magmatic zircon edges and some round zircons define an upper intercept age of 3155 ± 17 Ma which could represent overgrowths during gneissification. It appears that the TGB was not affected by the events posterior to its genesis, i.e. the Liberian (2.9-2.7 Ga) and Eburnean (2.4-2.0 Ga) events. Additionally, the TGB proves to be a juvenile Leonian rock, as indicated by the Nd model age of 3456 Ma, and could also constitute the protolith of the granulitic grey gneisses and charnockites of the Man area, which are 150-400 Ma younger.

  6. Rock size-frequency distributions analysis at lunar landing sites based on remote sensing and in-situ imagery

    Science.gov (United States)

    Li, Bo; Ling, Zongcheng; Zhang, Jiang; Chen, Jian

    2017-10-01

    Rock populations can supply fundamental geological information about origin and evolution of a planet. In this paper, we used Lunar Reconnaissance Orbiter (LRO) narrow-angle camera (NAC) images to identify rocks at the lunar landing sites (including Chang'e 3 (CE-3), Apollo and Surveyor series). The diameter and area of each identified rock were measured to generate distributions of rock cumulative fractional area and size-frequency on a log-log plot. The two distributions both represented the same shallow slopes at smaller diameters followed by steeper slopes at larger diameters. A reasonable explanation for the lower slopes may be the resolution and space weathering effects. By excluding the smaller diameters, rock populations derived from NAC images showed approximately linear relationships and could be fitted well by power laws. In the last, the entire rock populations derived from both NAC and in-situ imagery could be described by one power function at the lunar landing sites except the CE-3 and Apollo 11 landing sites. This may be because that the process of a large rock breaking down to small rocks even fine particles can be modeled by fractal theories. Thus, rock populations on lunar surfaces can be extrapolated along the curves of rock populations derived from NAC images to smaller diameters. In the future, we can apply rock populations from remote sensing images to estimate the number of rocks with smaller diameters to select the appropriate landing sites for the CE-4 and CE-5 missions.

  7. Ellipsoidal anisotropy in elasticity for rocks and rock masses

    CERN Document Server

    Pouya, Ahmad

    2011-01-01

    One of the interesting features with the ellipsoidal models of anisotropy presented in this paper is their acceptance of analytical solutions for some of the basic elasticity problems. It was shown by Pouya (2000) and Pouya and Zaoui (2006) that many closed-form solutions for basic problems involving linear isotropic materials could be extended by linear transformation to cover a variety of "ellipsoidal" materials. This paper will describe two main varieties of ellipsoidal elastic models and show how well they fit the in situ data for sedimentary rocks; numerical homogenization results for several varieties of fractured rock masses will also be provided.

  8. An acoustic sensor for prediction of the structural stability of rock

    CSIR Research Space (South Africa)

    Brink, S

    2016-05-01

    Full Text Available m. The failure of hanging walls has been an area of extensive research in rock mechanics,1 as it is the cause of many rock fall-related injuries and deaths. This workplace risk to miners is addressed by various standard mining practices, one of which...

  9. Rock glaciers, protalus ramparts and pronival ramparts in the south-eastern Alps

    Science.gov (United States)

    Colucci, R. R.; Boccali, C.; Žebre, M.; Guglielmin, M.

    2016-09-01

    Rock glaciers and protalus ramparts are characteristic landforms of the periglacial domain often used as markers for the occurrence of permafrost in mountain terrains. As such, relict rock glaciers can be used for paleoclimate reconstructions. We present here the first previously unreported rock glacier inventory of the south-eastern Alps (including the north-eastern-most region of Italy and Slovenia), interpreted from high resolution orthophotos and a high resolution digital terrain model interpolated from airborne laser scanning (LiDAR). We mapped 53 rock glaciers covering a total area of 3.45 km2. The majority of rock glaciers are classified as relict and distributed between 1708 and 1846 m a.s.l. with slope ranging between 19° and 27°. In addition to rock glaciers we observed 66 protalus (pronival) ramparts, having median elevation of 1913 m a.s.l. and covering 0.48 km2. More than half of the inventoried protalus ramparts are located in the more maritime area of the Alps with higher precipitation compared to the location of rock glaciers. Using paleoclimate reconstruction based on the 1981-2010 climatological record of the area, we infer that the rock glaciers formed during one of the dry and cold periods of the late Pleistocene and early Holocene. Possible evolution of the active pronival forms observed in the most maritime area of this alpine sector is also discussed.

  10. Information base for waste repository design. Volume 3. Waste/rock interactions

    Energy Technology Data Exchange (ETDEWEB)

    Koplick, C.M.; Pentz, D.L.; Oston, S.G.; Talbot, R.

    1979-01-01

    This report describes the important effects resulting from interaction between radioactive waste and the rock in a nuclear waste repository. The state of the art in predicting waste/rock interactions is summarized. Where possible, independent numerical calculations have been performed. Recommendations are made pointing out areas which require additional research.

  11. Stress Evolution in Roadway Rock Bolts During Mining in a Fully Mechanized Longwall Face, and an Evaluation of Rock Bolt Support Design

    Science.gov (United States)

    Zhang, Kai; Zhang, Guimin; Hou, Rongbin; Wu, Yu; Zhou, Hongqi

    2015-01-01

    Rock bolts are widely used in coal mines throughout China. Approximately 8,000 km of roadways are excavated in coal mines every year in China, 80 % of which are supported by rock bolts. At present, the design of rock bolt support schemes is mainly based on analogies and experience from previous projects. In the present study, in order to evaluate the design of rock bolt support in roadways, several cross sections of a roadway were monitored for rock bolt stress during the roadway excavation and mining. The study results show that the stress in the rock bolts varied in the areas 20 m behind the excavating face and 30 m ahead of the mining face. For the rock bolts observed in this study, the max axial force was within the design limit of the bolts, thus the support design was shown to be acceptable. Then, numerical simulation was performed using FLAC3D to investigate the stress evolution in the rock bolts during the mining of the fully mechanized longwall face. The simulation results show an overall agreement with the in situ measurements. Finally, parametric study pertaining to length, anchorage length, and rock bolt spacing was carried out with the numerical model, and several suggestions for the support design were proposed.

  12. Astronauts Armstrong and Aldrin study rock samples during field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, and Astronaut Edwin Aldrin, Lunar module pilot for Apollo 11, study rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  13. The decapod and stomatopod Crustacea of St Paul's Rocks

    NARCIS (Netherlands)

    Holthuis, L.B.

    1980-01-01

    INTRODUCTION Saint Paul's Rocks (Penedos de São Pedro e São Paulo) are a small group of rocky islets on the mid-Atlantic ridge near the equator, occupying an area of roughly 250 by 425 m. There is no vegetation and, apart from birds and invertebrates, the islands are uninhabited. The Cambridge Exped

  14. Rock Cycle Sagas: The STRATegy COLUMN for Precollege Science Teachers.

    Science.gov (United States)

    Metzger, Ellen Pletcher

    1994-01-01

    Reviews The Best of BAESI: Earth Science Activities & Recommended Resources from the Bay Area Earth Science Institute. The Best of BAESI is divided into two parts. Part I contains 19 classroom activities on topographic maps, rocks and minerals, earthquakes, volcanoes, and plate tectonics. Part II describes resources and identifies government…

  15. Geotechnical issues and guidelines for storage of compressed air in excavated hard rock caverns

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Doherty, T.J.; Fossum, A.F.

    1982-04-01

    The results of a literature survey on the stability of excavated hard rock caverns are presented. The objective of the study was to develop geotechnical criteria for the design of compressed air energy storage (CAES) caverns in hard rock formations. These criteria involve geologic, hydrological, geochemical, geothermal, and in situ stress state characteristics of generic rock masses. Their relevance to CAES caverns, and the identification of required research areas, are identified throughout the text. This literature survey and analysis strongly suggests that the chief geotechnical issues for the development and operation of CAES caverns in hard rock are impermeability for containment, stability for sound openings, and hydrostatic balance.

  16. Engineering geological characterization of volcanic rocks of ethiopian and sardinian highlands to be used as construction materials

    OpenAIRE

    Engidasew, Tesfaye Asresahagne

    2014-01-01

    This thesis presents the results of the study conducted on the “Geoengineering characterization of volcanic rocks from Ethiopian and Sardinian highlands to be used as construction materials”. Though, the two project areas are geographically far apart, both are partly covered with volcanic rocks mainly consisting of basic and subordinate felsic rocks. The research was conducted in two countries; part I, the Ethiopian Project area located on the northwestern central Highlands of ...

  17. Optimization study on waterproofing coal and rock pillar between two working faces

    Energy Technology Data Exchange (ETDEWEB)

    Yang Liu; Xue-Zhou Chai; Jing-Sheng Li [Xi' an University of Science and Technology. Xi' an (China). School of Energy Engineering

    2009-02-15

    The routine method of designing the width of waterproofing coal and rock pillar between two working faces leads to the coal pillar size being too large and is wasteful of coal resources. The omission in this method of replacing the width of failure area by the displaced mass influence area was pointed out. A formula of coal pillar failure area width is given for waterproofing coal and rock design. It is recommended that coal pillars and rock pillars should be calculated separately first. The design method was corrected by replacing the width of failure area by the displaced mass influence area. This reduces the design width of coal pillars and optimizes the whole process of waterproof coal and rock pillars design. 6 refs., 3 figs.

  18. Attachable rock bolters for roadheaders

    Energy Technology Data Exchange (ETDEWEB)

    Weibezahn, K. [Wirth Maschinen- und Bohrgeraete-Fabrik GmbH, Erkelenz (Germany); West, M. [Deilmann-Haniel Mining Systems GmbH (Germany)

    2004-07-01

    Roadheaders are used in mining and tunnelling in medium hard rock formations. The excavated space is made safe either by NATM-technology or a steel support system. The application of a rock bolting system up to now was restricted to formations that can cope with at least some support lag. A new system was developed in close cooperation between WIRTH Maschinen- und Bohrgeraetefabrik GmbH and deilmann-haniel mining systems gmbh that allows to carry out rock bolting with two drill rigs whicht are attached to the cutting boom of the roadheader even in front of the cutter head directly after cutting. Alternatively a robot may be attached to above named system that enables remotely controlled shot-creting close to the face.

  19. Rocas para moler: análisis de procedencia de materias primas líticas para artefactos de molienda (área Interserrana Bonaerense Rocks For Grinding: Lithic Raw Material Provenience Studies Of Grinding Technology, Interserrana Area Of Buenos Aires Province, Argentina

    Directory of Open Access Journals (Sweden)

    Alejandra B. Matarrese

    2009-06-01

    Full Text Available Los artefactos de molienda representan frecuentemente grandes volúmenes de roca trasportados a los sitios arqueológicos del área Interserrana Bonaerense. En el contexto de los recientes estudios sistemáticos en relación a estos artefactos, en este trabajo se presentan los resultados de los análisis macroscópicos, de cortes delgados y de difracción de rayos X de una muestra de instrumentos confeccionados sobre materias primas sedimentarias y metamórficas. De manera complementaria, se consideran características de las formas-base y los pesos de parte de los artefactos estudiados. Los datos obtenidos se discuten respecto a la procedencia y estrategias de explotación de estos recursos líticos utilizados para los artefactos de molienda. Se identificó en los conjuntos estudiados el uso de rocas disponibles en afloramientos de los sistemas serranos pampeanos de Tandilia y Ventania e interserranos. El trasladado de estas materias primas líticas a los contextos bajo estudio implicaron diferentes esfuerzos de aprovisionamiento (locales, de media y de larga distancia. Las características petrográficas de las rocas seleccionadas para la producción de los artefactos de molienda se relacionan principalmente con una alta capacidad abrasiva. En algunos casos, se habrían aprovechado formas-base naturales aptas para ser usadas sin modificaciones previas. Estos datos comprenden un primer acercamiento a la gestión de recursos líticos para la manufactura y/o uso de artefactos de molienda por parte de grupos cazadores-recolectores prehispánicos pampeanos durante el Holoceno tardío.Grinding tools frequently comprise great volumes of rocks transported to the archaeological sites of the Interserrana area of Buenos Aires Province. The results from thin section and X-ray diffraction analyses of a sample of grinding artifacts manufactured from sedimentary and metamorphic raw material are presented in this paper in the context of recent systematic

  20. Geology and ground-water resources of Rock County, Wisconsin

    Science.gov (United States)

    LeRoux, E.F.

    1964-01-01

    Rock County is in south-central Wisconsin adjacent to the Illinois State line. The county has an area of about 723 square miles and had a population of about 113,000 in 1957 ; it is one of the leading agricultural and industrial counties in the State. The total annual precipitation averages about 32 inches, and the mean annual temperature is about 48 ? F. Land-surface altitudes are generally between 800 and 00 feet, but range from 731 feet, where the Rock River flows into Illinois, to above 1,080 feet, at several places in the northwestern part of the county. The northern part of Rock County consists of the hills and kettles of a terminal moraine which slopes southward to a flat, undissected outwash plain. The southeastern part of the county is an area of gentle slopes, whereas the southwestern part consists of steep-sided valleys and ridges. Rock County is within the drainage basin of the Rock River, which flows southward through the center of the county. The western and southwestern parts of ,the county are drained by the Sugar River und Coon Creek, both of which flow into the Pecatonica River in Illinois and thence into the Rock River. The southeastern part of the county is drained by Turtle Creek, which also flows into Illinois before joining the Rock River. Nearly all the lakes and ponds are in the northern one-third of the county, the area of most recent glaciation. The aquifers in Rock County are of sedimentary origin and include deeply buried sandstones, shales, and dolomites of the Upper Cambrian series. This series overlies crystalline rocks of Precambrian age and supplies water to all the cities and villages in the county. The St. Peter sandstone of Ordovician age underlies all Rock County except where the formation has been removed by erosion in the Rock and Sugar River valleys, and perhaps in Coon Creek valley. The St. Peter sandstone is the principal source of water for domestic, stock, and small industrial wells in the western half of the county

  1. Failure mechanism and supporting measures for large deformation of Tertiary deep soft rock

    Institute of Scientific and Technical Information of China (English)

    Guo Zhibiao; Wang Jiong; Zhang Yuelin

    2015-01-01

    The Shenbei mining area in China contains typical soft rock from the Tertiary Period. As mining depths increase, deep soft rock roadways are damaged by large deformations and constantly need to be repaired to meet safety requirements, which is a great security risk. In this study, the characteristics of deformation and failure of typical roadway were analyzed, and the fundamental reason for the roadway deformation was that traditional support methods and materials cannot control the large deformation of deep soft rock. Deep soft rock support technology was developed based on constant resistance energy absorption using constant resistance large deformation bolts. The correlative deformation mechanisms of surrounding rock and bolt were analyzed to understand the principle of constant resistance energy absorption. The new technology works well on-site and provides a new method for the excavation of roadways in Tertiary deep soft rock.

  2. 大别—苏鲁区超高压(UHP)变质岩的多阶段构造折返过程%Multi-Stage Tectonic Exhumation Processes of Ultrahigh-Pressure (UHP) Metamorphic Rocks in the Dabie-Sulu Area, East-Central China

    Institute of Scientific and Technical Information of China (English)

    索书田; 钟增球; 周汉文; 张利; 游振东

    2012-01-01

    Exhumation processes of ultrahigh-pressure (UHP) metamorphic rocks, by which these deep-seated rocks were rapidly returned from mantle depths of more than 100 km within deep subduction zones into the upper crust and to the surface, are of paramount importance for the understanding of the kinematics and dynamics of convergent plate margins and continental collision belts. At least four large successive stages of the exhumation process of UHP metamorphic rocks in the Dabie-Sulu area, east-central China, mainly based on structural, petrological, geochemical data and available geochronological data, combined with previously regional polyphased deformation analyses, can be distinguished. Massive eclogites recorded the deep continental subduction/collision between the Sino-Korean and Yangtze cratons during the Triassic (~250-230 Ma). The early exhumation occurred after the peak of UHP metamorphism at conditions of up to >3. 1-4. 0 Gpa and 800±50 ℃ , which may correspond to the Dz regional deformation phase and took place at mantle depths, displaying the model of vertical ductile extrusion, within the coesite stability field. The subsequent exhumation stages, corresponding with D3, D4 and D5 regional deformation phase, respectively, and two intermediate tectono-thermal events, I. E. , the formation of the granulite/amphibolite facies symplectite or corona and the generation of extensive partial melting, occurred in crustal levels. Shear zones of an anastomosing rheological type were developed at diffterent stages and depths, indicating that the partitioning of deformation and metamorphism within the UHP metamorphic belt repeated. These imply that the exhumation of the UHP rocks is a complex tectonic process, in response to subduction/collision or extension of the continental crust, and is strongly constrained by a number of internal and external factors of the belt. In particular, fluids play important roles in the exhumation process of UHP rocks in the Dabie

  3. DAMAGE MODEL OF CONTROL FISSURE IN PERILOUS ROCK

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong-kai; TANG Hong-mei; YE Si-qiao

    2006-01-01

    Hitherto, perilous rock is the weakest topic in disasters studies. Specially,damage of control fissure under loads is one key technique in study of develop mechanism of perilous rock. Damage division of end area of control fissure was defined by authors,then calculation methods of timed-Poisson's ratio and timed-Young's modulus were established in damage mechanics theory. Further, the authors set up damage constitutive equation of control fissure, which founds important basis to numerical simulation for control fissure to develop.

  4. Study of the optimization of shooting lithology and the technology of static correction in the area developed with igneous rock in near surface in XW%XW 表层火成岩发育区激发岩性优选及静校正技术研究

    Institute of Scientific and Technical Information of China (English)

    马永乐; 朱峰; 谢纯华; 石一青; 晋为真; 张寒松

    2016-01-01

    The distribution of near surface igneous rock in XW area is so complicated that there always exists the static correction problems.In the field operation,lithology and conformity of shooting were taken into consideration to get better data.Further,the optimized static correction and usage of uphole time are so helpful to improve the onsite processing sec-tion.Through the integrated data acquiring and data procession,such static correction problem has been resolved and the fi-nal data has been comparatively improved.%XW 地区近地表岩性复杂多变,地震资料中存在一定的静校正问题。在地震勘探中,通过优选激发岩性和改善激发的一致性,获得了较好的原始资料,并结合井口时间的应用和静校正方法的优选,改善了现场处理剖面的质量。通过这种采集、处理一体化的方式,在解决该地区静校正问题上,取得了较好的效果。

  5. Geochemistry of PGE in mafic rocks of east Khasi Hills, Shillong Plateau, NE India

    Indian Academy of Sciences (India)

    Sampa Hazra; Jyotisankar Ray; C Manikyamba; Abhishek Saha; S S Sawant

    2015-03-01

    The mafic rocks of east Khasi Hills of the Meghalaya Plateau, northeastern India, occur as an intrusive body which cut across the weakly metamorphosed Shillong Group of rocks. Other than Shillong Group of rocks, high grade Archaean gneissic rocks and younger porphyritic granites are also observed in the study area. The studied mafic rocks of east Khasi Hills cover an area of about 4 km2 and represent structurally controlled intrusion and varying grades of deformation. Structurally, these mafic rocks can be divided into massive type of mafic rocks, which are more or less deformation free and foliated type of mafic rocks that experienced deformation. Petrographically, this massive type can be classified as leuco-hornblende-gabbro whereas foliated type can be designated as amphibolite. On the basis of major oxide geochemistry, the investigated mafic rocks can be discriminated into high titanium (HT) (TiO2 > 2 wt%) and low titanium (LT) types (TiO2 < 2 wt%). Use of several geochemical variation diagrams, consideration of chondrite-normalized and mantle-normalized REE and PGE plots suggest role of magmatic differentiation (with almost no role of plagioclase fractionation) in a subduction controlled tectonic environment. The PGE trends of the studied rocks suggest relative enrichment of palladium group of PGE (PPGE) compared to iridium group PGE (IPGE). Critical consideration of Sm vs. La, Cu vs. La, Pd vs. La and Cu/Pd vs. La/Sm plots strongly favours generation of the parent magma at a columnar melting regime with batch melting of cylindrical column of the parent mantle to the tune of ∼25%. The characteristic PGE behaviours of the presently investigated mafic rocks of east Khasi Hills can be typically corroborated as `orogenic' (discordant) type. These rocks have an enriched mantle affinity with a co-magmatic lineage and they have been generated by slab-dehydration, wedge-melting and assimilation fractional crystallization process at a continental margin arc setting.

  6. Tests of Rock Cores Michigamme Study Area, Michigan

    Science.gov (United States)

    1970-06-01

    section also had been sheared, as several 45 I microfractures were present. Quartz was broken and strained; plagio - clase grains had granulated borders; and...Figure 4.6). The section was blackish-red, fine-graine potash granite that had been severely altered and sheared. Plagio - clase grains were broken and

  7. Rock Mechanics Aspects of Stoping Without Back-area Support

    CSIR Research Space (South Africa)

    King, RG

    1989-06-01

    Full Text Available stream_source_info King_1989.pdf.txt stream_content_type text/plain stream_size 92 Content-Encoding ISO-8859-1 stream_name King_1989.pdf.txt Content-Type text/plain; charset=ISO-8859-1 ...

  8. Effect of the rock properties on mining-induced seismicity around the Ventersdorp contact reef, Witwatersrand basin, South Africa

    CSIR Research Space (South Africa)

    Milev, AM

    2002-01-01

    Full Text Available The Ventersdorp Contact Reef is characterised by a variety of different rock types that are found above and below the reef in different mining areas. These variations in the host rock type have been classified into six main geotechnical areas...

  9. Application of High Density Resistivity Inversion Software in Copper Exploration and IP Sounding Inversion in Zouping Zhangqiu Volcano Rock Area%高密度电法反演软件在邹平章丘火山岩区铜矿勘查激电测深反演中的应用

    Institute of Scientific and Technical Information of China (English)

    杨宏智; 姚敏; 吕小红

    2016-01-01

    In the copper exploration in Zouping Zhangqiu volcanic rock area in Shandong province, in order to o⁃vercome false anomaly caused by topographical factor, by using high density resistivity software as RES2DINV, the inversion of induced polarization sounding data has been carried out. Combining geological data and induced cur⁃rent middle gradient data of the excitation, Low resistivity and high polarization anomaly is conducted. It is tested that is was caused by cooper ore body. If carrying out the work of IP in the complex terrain areas, this method can be applied to predicate and reduce the difficulty of drilling.%在山东省邹平章丘火山岩区铜矿勘查工作中,为了克服地形因素引起的假异常,使勘查成果接近实际地质情况,应用高密度电法反演软件RES2DINV软件进行了带地形的激电测深资料反演,结合地质资料及激电中梯资料,推断了低阻高极化异常体,经钻探验证异常体为铜矿体引起。在地形复杂地区开展激电工作,可以应用此方法,减小预布验证钻孔难度。

  10. Inelastic deformation in crystalline rocks

    Science.gov (United States)

    Rahmani, H.; Borja, R. I.

    2011-12-01

    The elasto-plastic behavior of crystalline rocks, such as evaporites, igneous rocks, or metamorphic rocks, is highly dependent on the behavior of their individual crystals. Previous studies indicate that crystal plasticity can be one of the dominant micro mechanisms in the plastic deformation of crystal aggregates. Deformation bands and pore collapse are examples of plastic deformation in crystalline rocks. In these cases twinning within the grains illustrate plastic deformation of crystal lattice. Crystal plasticity is governed by the plastic deformation along potential slip systems of crystals. Linear dependency of the crystal slip systems causes singularity in the system of equations solving for the plastic slip of each slip system. As a result, taking the micro-structure properties into account, while studying the overall behavior of crystalline materials, is quite challenging. To model the plastic deformation of single crystals we use the so called `ultimate algorithm' by Borja and Wren (1993) implemented in a 3D finite element framework to solve boundary value problems. The major advantage of this model is that it avoids the singularity problem by solving for the plastic slip explicitly in sub steps over which the stress strain relationship is linear. Comparing the results of the examples to available models such as Von Mises we show the significance of considering the micro-structure of crystals in modeling the overall elasto-plastic deformation of crystal aggregates.

  11. Los abuelos de nuestro rock

    Directory of Open Access Journals (Sweden)

    Jacobo Celnik

    2016-12-01

    Full Text Available Los Yetis. Una bomba atómica a go go. La historia de los abuelos de nuestro rock. Diego Londoño; Pulso & Letra Editores, Instituto para el Desarrollo de Antioquia, Instituto de Cultura y Patrimonio de Antioquia, 2014, 98 págs., fotografías.

  12. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>20131550 Bai Jinfeng(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang 065000,China);Bo Wei Determination of 36Elements in Geochemical Samples by High Resolution Inductively Coupled Plasma-Mass Spectrometry(Rock and Mineral Analysis,ISSN0254-5357,CN11-2131/TD,31(5),2012,p.814

  13. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    <正>20050704 Cheng Lin (Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039, China); Feng Songlin Analysis of Colored Elements in Ancient Colored Glaze by SRXRF (Rock and Mineral Analysis, ISSN0254-5357, CN11 -2131/TD, 23 (2), 2004, p. 113-116, 120, 3 illus. , 3 tables, 6 refs. )

  14. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20142093Chen Daohua(Guangzhou Marine Geological Survey,Guangzhou 510075,China);Diao Shaobo The Latest Progress of Geological Marine Testing Technology in China(Rock and Mineral Analysis,ISSN0254-5357,CN11-2131/TD,32(6),2013,p.850-859,105refs.)Key words:chemical analysis,China

  15. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>20070252 Chen Meilan (Biological and Environmental College, Zhejiang Shuren University, Hangzhou 310015, China); Li Li Study on Adsorption of Phenol by Modified Organobentonite (Rock and Mineral Analysis, ISSN0254-5357, CN11-2131/TD, 24(4), 2005, p.259-261, 267, 6 illus., 1 table, 11 refs.) Key words: bentonite, benzene, adsorption

  16. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    20160255 Wang Na(Tianjin Center of Geologica