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  1. Metallogenic belt and mineral deposit maps of northeast Asia

    Science.gov (United States)

    Obolenskiy, Alexander A.; Rodionov, Sergey M.; Dejidmaa, Gunchin; Gerel, Ochir; Hwang, Duk-Hwan; Miller, Robert J.; Nokleberg, Warren J.; Ogasawara, Masatsugu; Smelov, Alexander P.; Yan, Hongquan; Seminskiy, Zhan V.

    2013-01-01

    This report contains explanatory material and summary tables for lode mineral deposits and placer districts (Map A, sheet 1) and metallogenic belts of Northeast Asia (Maps B, C, and D on sheets 2, 3, and 4, respectively). The map region includes eastern Siberia, southeastern Russia, Mongolia, northeast China, and Japan. A large group of geologists—members of the joint international project, Major Mineral Deposits, Metallogenesis, and Tectonics of Northeast Asia—prepared the maps, tables, and introductory text. This is a cooperative project with the Russian Academy of Sciences, Mongolian Academy of Sciences, Mongolian National University, Ulaanbaatar, Mongolian Technical University, Mineral Resources Authority of Mongolia, Geological Research Institute, Jilin University, China Geological Survey, Korea Institute of Geoscience and Mineral Resources, Geological Survey of Japan, and U.S. Geological Survey. This report is one of a series of reports on the mineral resources, geodynamics, and metallogenesis of Northeast Asia. Companion studies include (1) a detailed geodynamics map of Northeast Asia (Parfenov and others, 2003); (2) a compilation of major mineral deposit models (Rodionov and Nokleberg, 2000; Rodionov and others, 2000); (3) a series of metallogenic belt maps (Obolenskiy and others, 2004); (4) location map of lode mineral deposits and placer districts of Northeast Asia (Ariunbileg and others, 2003b); (5) descriptions of metallogenic belts (Rodionov and others, 2004); (6) a database on significant metalliferous and selected nonmetalliferous lode deposits and selected placer districts (Ariunbileg and others, 2003a); and (7) a series of summary project publications (Ariunbileg and 74 others, 2003b).

  2. Paired Magmatic-Metallogenic Belts in Myanmar - an Andean Analogue?

    Science.gov (United States)

    Gardiner, Nicholas; Robb, Laurence; Searle, Michael; Morley, Christopher

    2015-04-01

    contrasting minerals endowment. The Mogok-Mandalay-Mergui (MMM) Belt hosts crustal-melt S-type granites with significant tin-tungsten mineralization, and contains the historically major tungsten deposit of Mawchi. The Wuntho-Popa Arc comprises I-type granites and granodiorites with porphyry-type copper-gold and epithermal gold mineralization, and includes the world-class Monywa copper mine. Recent U-Pb radiometric age dating has shown the potential for the two belts to be both active from the Late Cretaceous to Eocene. The spatial juxtaposition of these two sub-parallel belts, the implication of contemporary magmatism, and their distinct but consistent metallogenic endowment bears strong similarities to the metallogenic belts of the South American Cordillera. Here we investigate whether they together represent the magmatic and metallogenic expression of an Andean-type setting in Myanmar during the subduction of Neo-Tethys. In this analogue the Wuntho-Popa Arc represents a proximal I-type magmatic belt sited immediately above the eastwards-verging Neo-Tethys subduction zone. Exhibiting porphyry-type copper-gold and epithermal gold mineralization, this would therefore be the Myanmar equivalent of the Andean coastal copper belts. Conversely, the parallel MMM Belt, comprised of more distal crustal-melt S-type tin granites, would have an analogue in the Bolivian tin belt.

  3. Yanshanian Magma-Tectonic-Metallogenic Belt in East China of Circum-Pacific Domain (Ⅱ): Lithosphere-Asthenosphere System and Metallogenic Environment

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    This paper shows that the catastrophe of lithosphere-asthenosphere system (LAS) is developed for the Yanshanian metallogenic belt in the East China. Two types of Yanshanian disturbed LAS and metallogenesis in the East China are recognized: great lithosphere thinning and thickening in the compressional orogenic environment, and the related Andes-type and Hercyn-type metallogenesis,respectively. Great amount of the juvenile and hot mantle materials and the reactivated hot lower crustal materials replaced, heated and injected into the cold lithosphere and crust are believed to be a fundamental source and a basic deep environment for the Yanshanian metallogenic explosion. Reactivated and active discontinuities on the lithosphere scale are considered to be the main ore-storing space of the metallogenic zone. Large magma-tectonic-metallogenic system is necessary for the formation of large cluster area of ore deposit. The eastern China is believed to have large potential for prospecting of ore deposits in terms of the metallogenic environment.

  4. 秘鲁国金属矿成矿带%METALLOGENIC BELTS IN PERU

    Institute of Scientific and Technical Information of China (English)

    刘良根; 蒋科; 黄什

    2014-01-01

    秘鲁国金属成矿带划分依据为秘鲁境内的主要断层系统、有利成矿作用的岩性及矿化年代、已发现226个矿床(点)的地质特征和空间分布,共划分为24个成矿带。本文对每个成矿带的名称、分布、控矿地层、构造、岩浆岩及成矿时间逐一进行论述,并列出成矿带里典型矿床名称、资源量及品位情况。%Metallogenic belts in Peru are divided into 24 by major fault system, lithology favorable to metallogenic process, time of mineralization, geological features and spatial distribution of 226 known ore deposits (prospects) in the country. This paper discussed the name, distribution, ore-control stratum, structure, magmatic rock and metallogenic time of each belt and listed the name, resource and grade of typical ore deposit of the belts.

  5. TECTONIC SETTING AND METALLOGENESIS OF THE PRINCIPAL SECTORS OF THE TETHYAN EURASIAN METALLOGENIC BELT

    Institute of Scientific and Technical Information of China (English)

    Slobodan; Jankovic

    2001-01-01

    Three global metallogenic belts were formed in the world during Mesozoic and post-Mesozoic times. Two of them are situated along the western and eastern Pacific margins, and the third one - the Tethyan Eurasian metallogenic belt (TEMB) is related to the domain of Eurasian plate and flanked on the south by the Afro-Arabian and Indian plates. The general tectonic evolution of the realm where the TEMB was formed is closely connected with the history of Tethys. The emplacement of ore deposits and the development of regional metallogenic units are related to a definitive time interval and to specific tectonic settings such as: (1) Intracontinental rifting along the northern margin of Gondwana and/or fragments already separated; (2) Oceanic environments (i.e. ophiolite complexes and ocean floor sediments) host podiform chromite deposits, volcano-sedimentary cupriferous pyrite deposits (Cyprus type), stratiform manganese deposits, and sporadically PGE deposits; (3) Subduction related settings involve mainly porphyry copper deposits, hydrothermal massive sulphide polymetallic deposits, and epithermal deposits. So far identified mineralization of porphyry copper exceeds in the TEMB over 100 million tons of copper metal; and(4) Collision and post-collision continent-continent setting includes deposits of lead-zinc, antimony, gold, in some sectors tin deposits, as well. The giant deposits of Li-pegmatite occur sporadically.The TEMB is almost a continuously mineralized belt, but within it, some sectors display specific features of tectonic settings, association of elements, minerals and morphogenetic types of mineralization.

  6. Temporal evolution of granitic magmas in the Luanchuan metallogenic belt, east Qinling Orogen, central China: Implications for Mo metallogenesis

    Science.gov (United States)

    Li, Dong; Han, Jiangwei; Zhang, Shouting; Yan, Changhai; Cao, Huawen; Song, Yaowu

    2015-11-01

    The Luanchuan metallogenic belt, located within the eastern part of the Qinling Orogen, central China, hosts a number of world-class Mo deposits that are closely related to small late Mesozoic granitic plutons. Zircon U-Pb dating of distinct plutons in the Luanchuan metallogenic belt has yielded ages of 153 ± 1, 154 ± 2, 152 ± 2, and 148 ± 1 Ma. Molybdenite Re-Os isotopic compositions of Yuku ore district in the southern part of Luanchuan metallogenic belt has yielded an isochron age of 146 ± 1 Ma, which is consistent with the large-scale mineralization ages in the northern part of the Luanchuan metallogenic belt. A combination of previous studies and new geochronological and isotopic data show a concordant temporal and genetic link between granitic magmatism and Mo mineralization in the Luanchuan metallogenic belt, suggesting that this mineralization episode formed the most extensive Mo mineralization belt in the east Qinling Orogen. Zircon grains from Mo-related granitic plutons show similar trace element distributions. High-precision Multi Collector-Inductively Coupled Plasma-Mass Spectrometry (MC-ICP-MS) Pb isotope analysis of K-feldspar megacrysts from mineralization-related granites suggest that they were derived from the lower crust. Similarly, the Pb isotopic compositions of pyrite coprecipitated with molybdenite also suggest that the metals were derived form the lower crust, with probably minor mantle contribution. A continuum mineralization model that describes the sourcing of Mo from an evolving granitic magma over successive differentiation events, possibly in separate but connected magma chambers, could explain the remarkable Mo enrichment in the Luanchuan metallogenic belt. The volatile- and Mo-bearing granitic magmas ascended as diapirs from the deep crust, and were emplaced as dikes in the upper crust. Lithological differences between these Mo-bearing granites may relate to different stages in the evolution of individual magmas. Finally, ore

  7. Magmatism and polymetallic mineralization in southwestern Qinzhou-Hangzhou metallogenic belt, South China

    Science.gov (United States)

    Huang, Xudong; Lu, Jianjun; Wang, Rucheng; Ma, Dongsheng

    2016-04-01

    As Neoproterozoic suture zone between the Yangtze Block and Cathaysia Block, Qinzhou-Hangzhou metallogenic belt is one of the 21 key metallogenic belts in China. Intensive multiple-aged felsic magmatism and related polymetallic mineralization take place in this belt. Although Neoproterozoic, Paleozoic, Triassic granites and associated deposits have been found in southwestern Qinzhou-Hangzhou metallogenic belt, Middle-Late Jurassic (150-165 Ma) magmatism and related mineralization is of the most importance. Three major kinds of Middle-Late Jurassic granitoids have been distinguished. (Cu)-Pb-Zn-bearing granitoids are slightly differentiated, calc-alkaline and metaluminous dioritic to granodioritic rocks. Sn-(W)-bearing granites contain dark microgranular enclaves and have high contents of REE and HFSE, suggesting affinities of aluminous A-type (A2) granites. W-bearing granites are highly differentiated and peraluminous rocks. (Cu)-Pb-Zn-bearing granitoids have ɛNd(t) values of -11 ˜ -4 and ɛHf(t) values of -12 ˜ -7, corresponding to TDMC(Nd) from 1.4 to 1.8 Ga and TDMC(Hf) from 1.6 to 2.0 Ga, respectively. The ɛNd(t) values of W-bearing granites vary from -11 to -8 with TDMC(Nd) of 1.6 ˜ 1.9 Ga and ɛHf(t) values change from -16 to -7 with TDMC(Hf) of 1.5 ˜ 2.0 Ga. Compared with (Cu)-Pb-Zn-bearing granitoids and W-bearing granites, the Sn-(W)-bearing granites have higher ɛNd(t) (-8 ˜ -2) and ɛHf(t) (-8 ˜ -2) values and younger TDMC(Nd) (1.1 ˜ 1.6 Ga) and TDMC(Hf) (1.2 ˜ 1.8 Ga) values, showing a more juvenile isotopic character. Sn-(W)-bearing granites originate from partial melting of granulitized lower crust involved with some mantle-derived materials. W-bearing granites are derived from partial melting of crust. (Cu)-Pb-Zn-bearing granitoids are also derived from crust but may be influenced by more mantle-derived materials. For (Cu)-Pb-Zn deposits, skarn and carbonate replacement are the most important mineralization types. Cu ore bodies mainly

  8. Mineral Potential Mapping for Tungsten Polymetallic Deposits in the Nanling Metallogenic Belt, South China

    Institute of Scientific and Technical Information of China (English)

    Yue Liu; Qiuming Cheng; Qinglin Xia; Xinqing Wang

    2014-01-01

    The Nanling belt in South China has considerable resources of tungsten polymetallic commodities and is one of the most important metallogenic belts in the world. Data-driven weights-of-evidence (WofE) and fuzzy logic models are used to evaluate the tungsten polymetallic po-tential of the Nanling belt. Initially, seven ore-controlling factors derived from multi-source geospatial datasets (e.g., geological, geochemical, and geophysical) are used for data integration in the two models. Two mineral potential maps are generated that efficiently predicate the locations of the deposits. The WofE map predicate 81%of the deposits within 13.6%of the study area, whereas the fuzzy logic map predicate 81.5%of the deposits within 13%of the area. The predictive maps are syntheses of spatial association rules, which provide better understanding of those factors that control the distribution of mineralization and trigger eventual exploration work in new areas. Subsequently, in order to evaluate the success rate accuracy, the receiver operating characteristic curves and area under the curves (AUCs) for the two potential maps are constructed. The results show that the AUCs for the WofE and fuzzy logic models are 0.775 7 and 0.840 6, respectively. The higher AUC value for the fuzzy logic model implies that it delineate a greater number of favorable areas compared with the WofE model. Overall, the capabilities of both models for correctly classifying areas with existing mineral deposits are satisfactory.

  9. Investigation on the age of mineralization in the Sungun porphyry Cu-Mo deposit, NW Iran with a regional metallogenic perspective

    Science.gov (United States)

    Simmonds, Vartan; Moazzen, Mohssen; Mathur, Ryan

    2016-04-01

    The Sungun porphyry copper deposit (PCD) is located in NW Iran, neighbouring several other PCDs and prospects in the region and the Lesser Caucasus (south Armenia). It lies on the Urumieh-Dokhtar magmatic arc (UDMA), which formed through the northeast-ward subduction of the Neo-Tethyan oceanic crust beneath the Central Iranian plate during late-Mesozoic and early-Cenozoic [1], and hosts the porphyry copper metallogenic belt of Iran. The Sungun PCD is the second largest deposit in Iran with ore reserves of about 850 Mt at 0.62 wt% Cu and 0.01 wt% Mo and probable reserves over 1Gt. The monzonitic to quartz monzonitic porphyry stock intruded the upper Cretaceous carbonates and Eocene volcano-sedimentary rocks. It produced a skarn-type mineralization at its contact zone with the carbonate rocks, as well as vast hydrothermal alteration zones and porphyry-type Cu and Mo mineralization. The zircon U-Pb age of the host porphyry stock is about 22.5±0.4 to 20.1±0.4 Ma [2]. Re-Os dating of four molybdenite separates from this PCD shows ages ranging between 22.9±0.2 to 21.7±0.2 Ma, with an average of 22.57±0.2 Ma, corresponding to the early Miocene (Aquitanian). These ages indicate that both the porphyry stock and the Cu-Mo mineralization are post-collisional events, similar to many other deposits and prospects in NW and central Iran and south Armenia, and the mineralization occurred shortly after the emplacement of the host stock, corresponding better to the ages obtained from the marginal parts of the stock. Magmatism and mineralization in Sungun coincides with the third metallogenic epoch in the Lesser Caucasus (Eocene to Miocene; [3]), though it is considerably younger than all of the dated PCDs and prospects in the south Armenia. It also postdates Cu-Mo mineralizations in the Saheb Divan (35 Ma), Qaradagh batholith (31.22±0.28 to 25.19±0.19 Ma), as well as Haft Cheshmeh PCD (28.18±0.42 to 27.05±0.37 Ma) in NW Iran, while it seems to be coeval with the Kighal

  10. Imaging lithosphere structure and dynamic processes of a world-class metallogenic belt with passive and active seismic methods

    Science.gov (United States)

    Lu, Q.; Gu, Y.; Shi, D.; Yan, J.

    2012-12-01

    The lithosphere structure and deep processes are keys to understanding mineral system and ore-forming processes. Lithosphere-scale process could create big footprints or signatures which can be observed by geophysics methods. SinoProbe-03 has conducted a Transect exploration across middle and lower Yangtze Metallogenic Belt (YMT) in Eastern China. Broadband seismic, reflection seismic, wide-angle reflection and magnetotellurics survey were carried out along the Transect. Seismic reflection profiles and MT survey were also performed in Luzong, Tongling and Ningwu ore districts to construct 3D geological model. The resulting geophysical data provides new information which help to better understanding the lithosphere structure, deep processes and deformation history of the Metallogenic Belt. The major results are: (1) Lower velocity body at the top of upper mantle and a SE dipping high velocity body were imaged by teleseismic tomography beneath YMB; (2) Shear wave splitting results show NE parallel fast-wave polarization direction which parallel with tectonic lineament; (3) The reflection seismic data support the crustal-detachment model, the lower and upper crust was detached during contraction deformation near Tanlu fault and Ningwu volcanic basin; (4) Broadband and reflection seismic confirm the shallow Moho beneath YMB; (5) Strong correlation of lower crust reflectivity with magmatism. All these features suggest that introcontinental subduction, lithosphere delamination, mantle sources magmatic underplating, and MASH process are responsible for the formation of wild-class metallogenic belt. Acknowledgment: We acknowledge the financial support of SinoProbe by the Ministry of Finance and Ministry of Land and Resources, P. R. China, under Grant sinoprobe-03, and financial support by National Natural Science Foundation of China under Grant 40930418

  11. Re–Os geochronology of Cu and W–Mo deposits in the Balkhash metallogenic belt, Kazakhstan and its geological significance

    Directory of Open Access Journals (Sweden)

    Xuanhua Chen

    2010-10-01

    Full Text Available The Central Asian metallogenic domain (CAMD is a multi-core metallogenic system controlled by boundary strike-slip fault systems. The Balkhash metallogenic belt in Kazakhstan, in which occur many large and super-large porphyritic Cu–Mo deposits and some quartz vein- and greisen-type W–Mo deposits, is a well-known porphyritic Cu–Mo metallogenic belt in the CAMD. In this paper 11 molybdenite samples from the western segment of the Balkhash metallogenic belt are selected for Re–Os compositional analyses and Re–Os isotopic dating. Molybdenites from the Borly porphyry Cu deposit and the three quartz vein-greisen W–Mo deposits—East Kounrad, Akshatau and Zhanet—all have relatively high Re contents (2712–2772 μg/g for Borly and 2.267–31.50 μg/g for the other three W–Mo deposits, and lower common Os contents (0.670–2.696 ng/g for Borly and 0.0051–0.056 ng/g for the other three. The molybdenites from the Borly porphyry Cu–Mo deposit and the East Kounrad, Zhanet, and Akshatau quartz vein- and greisen-type W–Mo deposits give average model Re–Os ages of 315.9 Ma, 298.0 Ma, 295.0 Ma, and 289.3 Ma respectively. Meanwhile, molybdenites from the East Kounrad, Zhanet, and Akshatau W–Mo deposits give a Re–Os isochron age of 297.9 Ma, with an MSWD value of 0.97. Re–Os dating of the molybdenites indicates that Cu–W–Mo metallogenesis in the western Balkhash metallogenic belt occurred during Late Carboniferous to Early Permian (315.9–289.3 Ma, while the porphyry Cu–Mo deposits formed at ∼316 Ma, and the quartz vein-greisen W–Mo deposits formed at ∼298 Ma. The Re–Os model and isochron ages thus suggest that Late Carboniferous porphyry granitoid and pegmatite magmatism took place during the late Hercynian movement. Compared to the Junggar-East Tianshan porphyry Cu metallogenic belt in northwestern China, the formation of the Cu–Mo metallogenesis in the Balkhash metallogenic belt occurred between that of

  12. Crutal and upper mantle structure beneath the mid-lower Yangtze metallogenic belt revealed by passive-source seismic array

    Science.gov (United States)

    Shi, D.; Lu, Q.; Yan, J.; Xu, W.; Zhang, G.; Jiang, G.; Dong, S.

    2010-12-01

    The mid-lower reach of Yangtze River is an important metallogenic belt in Eastern China. To understand the formation and geodynamic process for the mineral deposits, SinoProbe program carries out a multidisciplinary trans-section in this region, including active-source methods such as near-vertical (NV) and wide-angle reflection(WA) seismic reflections, passive-source methods such as broadband seismic array(BB) and magnetotellurics (MT), and geochemical and geological observations. The broadband seismic array was initiated in November, 2009, which was deployed in a linear profile, and will record for ~ 1 year. Other geophysical components are planed to be initiated in 2011. The BB array is composed of 52 stations with a much denser spatial interval of ~5 km, starts from Liyang in Jiangsu province in the southeast, across the Yangtze metallogenic belt and the Tanlu fault and then ends in the North China Block (NCB) in the northwest. Based upon the data available at present, preliminary teleseismic receiver function cross-sections have been achieved. The preliminary results show a clear variation of Moho depths along the profile, which, we believe, shed lights on the gloomy and complicated geodynamic process. The Moho is seen around 30 km deep along the profile, becoming moderately shallow to ~27 km beneath the Yangtze metallogenic belt, getting gradually deeper across the Tanlu fault and reaching to a depth of ~32 km beneath the north end of profile in the NCB. In addition to the Moho structure, we have observed some intra-crustal converters and significant scattering energy from the Tanlu fault on the receiver function profile. More methods have been applying to the BB dataset. More detailed descriptions of the field experiment and coming results from this passive-source experiment will be presented. ACKNOWLEDGMENTS We acknowledge the financial support of SinoProbe by the Ministry of Finance and Ministry of Land and Resources, P. R. China, under Grant sinoprobe-03

  13. CRED REA Fish Team Belt Transect Survey at Kure Atoll, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Kure Atoll in the NW...

  14. CRED REA Fish Team Belt Transect Survey at Midway, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Midway in the NW...

  15. CRED REA Fish Team Belt Transect Survey at Maro Reef, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Maro Reef in the NW...

  16. Appendix C: Summary of Major Metallogenic Belts in Northeast Asia (the Russian Far East, Yakutia, Siberia, Transbaikalia, Northern China, Mongolia, South Korea, and Japan)

    Science.gov (United States)

    Rodionov, Sergey M.; Obolenskiy, Alexander A.; Distanov, Elimir G.; Badarch, Gombosuren; Dejidmaa, Gunchin; Hwang, Duk-Hwan; Khanchuk, Alexander I.; Ogasawara, Masatsugu; Nokleberg, Warren J.; Parfenov, Leonid M.; Prokopiev, Andrei V.; Seminskiy, Zhan V.; Smelov, Alexander P.; Yan, Hongquan; Davydov, Yuriy V.V.; Fridovskiy, Valeriy Yu.; Gamyanin, Gennandiy N.; Gerel, Ochir; Kostin, Alexei V.; Letunov, Sergey A.; Li, Xujun; Nikitin, Valeriy M.; Ratkin, Vladimir V.; Shpikerman, Vladimir I.; Sudo, Sadahisa; Sotnikov, Vitaly I.; Spiridonov, Alexander V.; Stepanov, Vitaly A.; Sun, Fengyue; Sun, Jiapeng; Sun, Weizhi; Supletsov, Valeriy M.; Timofeev, Vladimir F.; Tyan, Oleg A.; Vetluzhskikh, Valeriy G.; Wakita, Koji; Yakovlev, Yakov V.; Zorina, Lydia M.

    2010-01-01

    The major purposes of this chapter are to provide (1) an overview of the regional geology, tectonics, and metallogenesis of Northeast Asia for readers who are unfamiliar with the region, (2) a general scientific introduction to the succeeding chapters of this volume, and (3) an overview of the methodology of metallogenic and tectonic analysis used in this study. We also describe how a high-quality metallogenic and tectonic analysis, including construction of an associated metallogenic-tectonic model will greatly benefit other mineral resource studies, including synthesis of mineral-deposit models; improve prediction of undiscovered mineral deposit as part of a quantitative mineral-resource-assessment studies; assist land-use and mineral-exploration planning; improve interpretations of the origins of host rocks, mineral deposits, and metallogenic belts, and suggest new research. Research on the metallogenesis and tectonics of such major regions as Northeast Asia (eastern Russia, Mongolia, northern China, South Korea, and Japan) and the Circum-North Pacific (the Russian Far East, Alaska, and the Canadian Cordillera) requires a complex methodology including (1) definitions of key terms, (2) compilation of a regional geologic base map that can be interpreted according to modern tectonic concepts and definitions, (3) compilation of a mineral-deposit database that enables a determination of mineral-deposit models and clarification of the relations of deposits to host rocks and tectonic origins, (4) synthesis of a series of mineral-deposit models that characterize the known mineral deposits and inferred undiscovered deposits in the region, (5) compilation of a series of metallogenic-belt belts constructed on the regional geologic base map, and (6) construction of a unified metallogenic and tectonic model. The summary of regional geology and metallogenesis presented here is based on publications of the major international collaborative studies of the metallogenesis and

  17. The lithosphere architecture and geodynamic of the Middle and Lower Yangtze metallogenic belt in eastern China: constraints from integrated geophysical data

    Science.gov (United States)

    Lü, Qingtian; Shi, Danian; Jiang, Guoming; Dong, Shuwen

    2014-05-01

    The lithosphere structure and deep processes are keys to understanding mineral system and ore-forming processes. Lithosphere-scale process could create big footprints or signatures which can be observed by geophysics methods. SinoProbe has conducted an integrated deep exploration across middle and lower reaches of Yangtze Metallogenic Belt (YMB) in Eastern China, these included broadband seismic, reflection seismic, wide-angle reflection and magnetotellurics survey. Seismic reflection profiles and MT survey were also performed in Luzong, Tongling and Ningwu ore districts to construct 3D geological model. The resulting geophysical data provides new information which help to better understanding the lithosphere structure, geodynamic, deformation and heat and mass transportation that lead to the formation of the Metallogenic Belt. The major results are: (1) Lower velocity body at the top of upper mantle and a SE dipping high velocity body were imaged by teleseismic tomography beneath YMB; (2) Shear wave splitting results show NE parallel fast-wave polarization direction which parallel with tectonic lineament; (3) The reflection seismic data support the crustal-detachment model, the lower and upper crust was detached during contraction deformation near Tanlu fault and Ningwu volcanic basin; (4) Broadband and reflection seismic confirm the shallow Moho beneath YMB; (5) Strong correlation of lower crust reflectivity with magmatism; (6) The lower crust below Luzong Volcanics shows obvious reflective anisotropy both at the crust-mantle transition and the brittle-ductile transition in the crust. All these features suggest that introcontinental subduction, lithosphere delamination, mantle sources magmatic underplating, and MASH process are responsible for the formation of this Mesozoic metallogenic belt. Acknowledgment: We acknowledge the financial support of SinoProbe by the Ministry of Finance and Ministry of Land and Resources, P. R. China, under Grant sinoprobe-03, and

  18. The lithosphere structure and deep processes of the Mesozoic metallogenic belt in eastern China: constraints from passive and active seismic methods

    Science.gov (United States)

    Lu, Q.; Shi, D.; Jiang, G.; Yan, J.

    2013-12-01

    The lithosphere structure and deep processes are keys to understanding mineral system and ore-forming processes. Lithosphere-scale process could create big footprints or signatures which can be observed by geophysics methods. SinoProbe-03 has conducted a Transect exploration across middle and lower Yangtze Metallogenic Belt (YMT) in Eastern China. Broadband seismic, reflection seismic, wide-angle reflection and magnetotellurics survey were carried out along the Transect. Seismic reflection profiles and MT survey were also performed in Luzong, Tongling and Ningwu ore districts to construct 3D geological model. The resulting geophysical data provides new information which help to better understanding the lithosphere structure, deep processes and deformation history of the Metallogenic Belt. The major results are: (1) Lower velocity body at the top of upper mantle and a SE dipping high velocity body were imaged by teleseismic tomography beneath YMB; (2) Shear wave splitting results show NE parallel fast-wave polarization direction which parallel with tectonic lineament; (3) The reflection seismic data support the crustal-detachment model, the lower and upper crust was detached during contraction deformation near Tanlu fault and Ningwu volcanic basin; (4) Broadband and reflection seismic confirm the shallow Moho beneath YMB; (5) Strong correlation of lower crust reflectivity with magmatism; (6) The lower crust below Luzong Volcanics shows obvious reflective anisotropy both at the crust-mantle transition and the brittle-ductile transition in the crust. All these features suggest that introcontinental subduction, lithosphere delamination, mantle sources magmatic underplating, and MASH process are responsible for the formation of this Mesozoic metallogenic belt. Acknowledgment: We acknowledge the financial support of SinoProbe by the Ministry of Finance and Ministry of Land and Resources, P. R. China, under Grant sinoprobe-03, and financial support by National Natural

  19. 基于MORPAS多元信息成矿预测研究--以上黑龙江成矿带为例%Multi-informational MORPAS Gold Metallogenic Prediction-Taking Upper Heilongj iang Metallogenic Belt as Example

    Institute of Scientific and Technical Information of China (English)

    杨吉波; 员俊杰; 周殿宇; 李师白

    2014-01-01

    Uppert Heilongjiang metallogenic belt is mainly composed of the early-Middle Jurassic coal bearing clastic rock in River-Lake-pluvial facies.At present,a number of small and medium-sized deposits have been found,so it is great significance for metallogenic prediction in the area.In this article,multi-source data sets including geological,geophysical,geochemical elsdatawer eintegr ated for mineral poten-tial mapping by using MORPAS technology. Furthermore these deposit recognition criteria layers were combined in the weight of evidence model,which used the spatial correlations between the evidence layers and the known mineral occurrences,to calculate the posterior probability and indentify the delineated pro-spective area.%上黑龙江成矿带主要由早中侏罗世河流湖泊洪积相含煤碎屑岩组成,目前已发现多个中小型矿床,在该区进行成矿预测意义重大。利用 MORPAS成矿预测系统,采用证据权重法进行成矿预测工作,在充分研究区内已知矿床的成矿规律基础上,以1∶25万比例的地质图为背景,物化探异常分析子系统对1∶20万区域化探数据进行C-A分形确定异常下限,综合现有的找矿标志,提取有利的成矿要素,进行针对处理,制成上黑龙江成矿带 MORPAS金成矿预测分析图,提供成矿靶区,为森林高覆盖区提供找矿有利条件。

  20. A preliminary study of NW Zhejiang foreland fold and thrust belt in Southeast China

    Institute of Scientific and Technical Information of China (English)

    肖文交; 李继亮; 何海清; 陈海泓

    1997-01-01

    The Upper Permian Dalong Formation (P2d) and Changxing Formation (P2c), and the Lower Tri-assic Zhengtang Formation (Tiz) are of deep-water turbidites. The sedimentary features of the NW Zhejiang are of SE-dipping passive continental margin from the Paleozoic to the early Triassic. Together with the foreland molasse basin during the late Triassic (T3w), the tectonics of the NW Zhejiang is characterised by a tectogenesis which took place in the middle Triassic. From SE to NW, the structural style varies from multi-duplex, antiformal stack to imbricate fans, and then to Jura Mountain-type fold zone with fold-style varying gradually from large-scale tight fold to mid-scale chevron fold, then to cylindrical fold, reviewing a preliminary scenario of foreland fold and thrust belt. The space-distributed structures and the tectonic vergence indicate the significance of deformation in (T1-T3).

  1. Metasomatism of ferroan granites in the northern Aravalli orogen, NW India: geochemical and isotopic constraints, and its metallogenic significance

    Science.gov (United States)

    Kaur, Parampreet; Chaudhri, Naveen; Hofmann, Albrecht W.; Raczek, Ingrid; Okrusch, Martin; Skora, Susanne; Koepke, Jürgen

    2014-06-01

    The late Palaeoproterozoic (1.72-1.70 Ga) ferroan granites of the Khetri complex, northern Aravalli orogen, NW India, were extensively metasomatised ~900 Ma after their emplacement, at around 850-830 Ma by low-temperature (ca. 400 °C) meteoric fluids that attained metamorphic character after exchanging oxygen with the surrounding metamorphic rocks. Albitisation is the dominant metasomatic process that was accompanied by Mg and Ca metasomatism. A two-stage metasomatic model is applicable to all the altered ferroan intrusives. The stage I is represented by a metasomatic reaction interface that developed as a result of transformation of the original microcline-oligoclase (An12-14) granite to microcline-albite (An1-3) granite, and this stage is rarely preserved. In contrast, the stage II metasomatic reaction front, where the microcline-bearing albite granite has been transformed to microcline-free albite granite, is readily recognisable in the field and present in most of the intrusives. Some of them lack an obvious reaction interface due to the presence of stage II albite granites only. When studied in isolation, these intrusives were incorrectly classified and their tectonic setting was misinterpreted. Furthermore, our results show that the mafic mineralogy of metasomatised granites has a significant impact on the characterisation of such rocks in the magmatic classification and discrimination diagrams. Nevertheless, the stage I metasomatised granites can be appropriately characterised in these diagrams, whereas the characterisation of the stage II granites will lead to erroneous interpretations. The close spatial association of these high heat producing ferroan granites with iron oxide-copper-gold (IOCG), U and REE mineralisation in the region indicates a genetic link between the metasomatism and the mineralisation. World-class IOCG, U and REE deposits are associated with metasomatised ferroan granites, suggesting that such a relationship may act as a critical

  2. Crustal structure and geodynamic of the Middle and Lower reaches of Yangtze metallogenic belt and neighboring areas: insights from deep seismic reflection profiling

    Science.gov (United States)

    Lu, Q.; Shi, D.; Liu, Z.; Zhang, Y.; Zhao, J.

    2014-12-01

    A 300 km deep seismic reflection profile across the middle and lower Yangtze River metallogenic belt (YRMB) and its adjacent areas established the architecture and geodynamic framework of the region. Results based on the interpretation of the deep seismic data include the deep complicated geometry of the Tan-Lu fault and Zhangbaling uplift, appears as a subvertical thrust fault with its deep portion dip toward the southeast, and along which the Zhangbaling uplift is squeezed out; complex upper crust deformation structure beneath Chuquan depression, within which there are both kink bands, thrusts, imbrication and fold structures reflecting contraction deformation, and detachment fault and normal-fault structures reflecting extensional deformation; the "crocodile" reflection structure emerging beneath the Tan-Lu fault and Ningwu-Lishui volcanic basin, i.e., the upper crust reflection thrust upward, and the lower crust reflection thrust downward and offsetting the Moho discontinuity, which reflects the decoupled deformation process of the upper and lower crust, and is interpreted as an intracontinental subduction. Further to the southeast, the upper crust deformation shows a large-scale "wave-form" pattern, making crustal scale syncline and anticline. The entire section of the reflection Moho is clearly discernible at depth of 30.0-34.5 km, and the Moho beneath the YRMB is shallowest, while the Moho beneath the North China block is deeper than that beneath the Yangtze block. Moho offsets could be seen beneath the Ningwu volcanic basin. Overall, the seismic data show evidence for an intracontinental orogeny and imposes constraints on the deep geodynamic model applied to study region. Our interpretation of seismic profile supports the view that the Yanshanian orogeny, due to the northwest subduction of the paleo-Pacific plate during the Middle-Late Jurassic, is the major event that shaped the tectonic framework of the region. A geodynamic model is proposed for the

  3. Hydrothermal Evolution of the Giant Cenozoic Kadjaran porphyry Cu-Mo deposit, Tethyan metallogenic belt, Armenia, Lesser Caucasus: mineral paragenetic, cathodoluminescence and fluid inclusion constraints

    Science.gov (United States)

    Hovakimyan, Samvel; Moritz, Robert; Tayan, Rodrik; Rezeau, Hervé

    2016-04-01

    The Lesser Caucasus belongs to the Central segment of the Tethyan metallogenic belt and it is a key area to understand the metallogenic evolution between the Western & Central parts of the Tethyan belt and its extension into Iran. Zangezur is the most important mineral district in the southernmost Lesser Caucasus. It is a component of the South Armenian block, and it was generated during the convergence and collision of the southern margin of the Eurasian plate and the northern margin of the Arabian plate, and terranes of Gondwana origin (Moritz et al., in press). The Zangezur ore district consists of the Tertiary Meghri-Ordubad composite pluton, which is characterized by a long-lasting Eocene to Pliocene magmatic, tectonic and metallogenic evolution. It hosts major porphyries Cu-Mo and epithermal Au - polymetallic deposits and occurrences, including the giant world class Kadjaran porphyry Cu-Mo deposit (2244 Mt reserves, 0.3% Cu, 0.05% Mo and 0.02 g/t Au). The Kadjaran deposit is hosted by a monzonite intrusion (31.83±0.02Ma; Moritz et al., in press). Detailed field studies of the porphyry stockwork and veins of the different mineralization stages, their crosscutting and displacement relationships and the age relationship between different paragenetic mineral associations were the criteria for distinction of the main stages of porphyry mineralization at the Kadjaran deposit. The economic stages being: quartz- molybdenite, quartz-molybdenite-chalcopyrite, and quartz-chalcopyrite. The main paragenetic association of the Kadjaran porphyry deposit includes pyrite, molybdenite, chalcopyrite, bornite, chalcocite, pyrrhotite, covellite, sphalerite, and galena. Recent field observations in the Kadjaran open pit revealed the presence of epithermal veins with late vuggy silica and advanced argillic alteration in the north-eastern and eastern parts of the deposit. They are distributed as separate veins and have also been recognized in re-opened porphyry veins and in

  4. Uranium Metallogenic Characteristics and Pattern in South-North Shuikoushan-Linwu Belt%水口山临武南北带铀成矿特征及成矿规律

    Institute of Scientific and Technical Information of China (English)

    何友宇; 姜必广; 覃金宁; 刘红兵; 周锡平

    2016-01-01

    水口山临武南北带铀成矿地质条件优越,前人经过多年的地质找矿工作,在带内先后发现了一批铀矿床(点)。笔者通过对该带铀矿床(点)的成矿地质背景、空间分布、矿化特征、成因类型等进行研究,总结了南北带内铀成矿特征及成矿规律。认为区域性隆起及边缘断陷带、深大断裂、背向斜和断层构造等是带内铀成矿的有利条件;带内成岩机制为“沉积变质动力破碎热液交代再动力破碎再热液交代”;铀矿床成因类型主要有热液型、热液叠加型和淋积型3种;各类型铀矿床的成矿模式,总体分为硅质岩系列、花岗岩系列和碳酸盐岩系列。%South-north belt of Shuikoushan and Linwu has favorite geological conditions for uranium met-allogenesis.After several years geological exploration,a batch of uranium deposits and occurrences have been found in this belt.The paper first discussed the metallogenic geological background,space distribu-tion of uranium deposit and occurrences,mineralization characteristic,genesis types in the south-north belt,then summarized the uranium metallogenic characteristic and metallogenic pattern.The regional up-lift and down faulted belt ,deep and large fault,anticline and syncline are believed beneficial for uranium mineralization.The rock-forming mechanism in the belt is “sedimentary metamorphism-power breaking-hydrothermal metasomatism-repower breaking-rehydrothermal metasomatism.There three mainly genesis types of uranium deposit in the belt:hydrothermal type,hydrothermal superposition type and leaching type.The metallogenic models of uranium deposit in the belt can be overall divided into silica rock series,granite series and carbonate series.

  5. U-Pb, Re-Os and Ar-Ar dating of the Linghou polymetallic deposit, Southeastern China: Implications for metallogenesis of the Qingzhou-Hangzhou metallogenic belt

    Science.gov (United States)

    Tang, Yanwen; Xie, Yuling; Liu, Liang; Lan, Tingguan; Yang, Jianling; Sebastien, Meffre; Yin, Rongchao; Liang, Songsong; Zhou, Limin

    2017-04-01

    The Qingzhou-Hangzhou metallogenic belt (QHMB) in Southeastern China has gained increasingly attention in recent years. However, due to the lack of reliable ages on intrusions and associated deposits in this belt, the tectonic setting and metallogenesis of the QHMB have not been well understood. The Linghou polymetallic deposit in northwestern Zhejiang Province is one of the typical deposits of the QHMB. According to the field relationships, this deposit consists of the early Cu-Au-Ag and the late Pb-Zn-Cu mineralization stages. Molybdenite samples with a mineral assemblage of molybdenite-chalcopyrite-pyrite ± quartz are collected from the copper mining tunnel near the Cu-Au-Ag ore bodies. Six molybdenite samples give the Re-Os model ages varying from 160.3 to 164.1 Ma and yield a mean age of 162.2 ± 1.4 Ma for the Cu-Au-Ag mineralization. Hydrothermal muscovite gives a well-defined Ar-Ar isochron age of 160.2 ± 1.1 Ma for the Pb-Zn-Cu mineralization. Three phases of granodioritic porphyry have been distinguished in this deposit, and LA-ICP-MS zircon U-Pb dating shows that they have formed at 158.8 ± 2.4 Ma, 158.3 ± 1.9 Ma and 160.6 ± 2.1 Ma, comparable to the obtained ages of the Cu-Au-Ag and Pb-Zn-Cu mineralization. Therefore, these intrusive rocks have a close temporal and spatial relationship with the Cu-Au-Ag and Pb-Zn-Cu ore bodies. The presences of skarn minerals (e.g., garnet) and vein-type ores, together with the previous fluid inclusion and H-O-C-S-Pb isotopic data, clearly indicate that the Cu-Au-Ag and Pb-Zn-Cu mineralization are genetically related to these granodiorite porphyries. This conclusion excludes the possibility that this deposit is of ;SEDEX; type and formed in a sag basin of continental rifts setting as previously proposed. Instead, it is proposed that the Linghou polymetallic and other similar deposits in the QHMB, such as the 150-160 Ma Yongping porphyry-skarn Cu-Mo, Dongxiang porphyry? Cu, Shuikoushan/Kangjiawang skarn Pb

  6. Geochronology, geochemistry, and mineralization of the granodiorite porphyry hosting the Matou Cu-Mo (±W) deposit, Lower Yangtze River metallogenic belt, eastern China

    Science.gov (United States)

    Zhu, Zhi-Yong; Jiang, Shao-Yong; Hu, Jian; Gu, Lian-Xing; Li, Jianwei

    2014-01-01

    Porphyry and skarn Cu-Fe-Au-Mo deposits are widespread in the Middle and Lower Yangtze River metallogenic belt (MLYMB), eastern China. The Matou deposit has long been regarded as a typical Cu-Mo porphyry deposit within Lower Yangtze part of the belt. Recently, we identified scheelite and wolframite in quartz veins in the Matou deposit, which is uncommon in other porphyry and skarn deposits in the MLYMB. We carried out detailed zircon U-Pb dating and geochemical and Sr-Nd-Hf isotopic studies of the granodiorite porphyry at Matou to define any differences from other ore-related granitoids. The porphyry shows a SiO2 content ranging from 61.85 wt.% to 65.74 wt.%, K2O from 1.99 wt.% to 3.74 wt.%, and MgO from 1.74 wt.% to 2.19 wt.% (Mg# value ranging from 45 to 55). It is enriched in light rare earth elements and large ion lithophile elements, but relatively depleted in Nb, Ta, Y, Yb and compatible trace elements (such as Cr, Ni, and V), with slight negative Eu anomalies (Eu/Eu* = 0.88-0.98) and almost no negative Sr anomalies. Results of electron microprobe analysis of rock-forming silicate minerals indicate that the Matou porphyry has been altered by an oxidized fluid that is rich in Mg, Cl, and K. The samples show relatively low ɛNd(t) values from -7.4 to -7.1, slightly high initial 87Sr/86Sr values from 0.708223 to 0.709088, and low ɛHf(t) values of zircon from -9.0 to -6.5, when compared with the other Cu-Mo porphyry deposits in the MLYMB. Zircon U-Pb dating suggests the Matou granodiorite porphyry was emplaced at 139.5 ± 1.5 Ma (MSWD = 1.8, n = 15), which is within the age range of the other porphyries in the MLYMB. Although geochemical characteristics of the Matou and other porphyries in the MLYMB are similar and all adakitic, the detrital zircons in the samples from Matou suggest that Archean lower crust (2543 ± 29 Ma, MSWD = 0.25, n = 5) was involved with the generation of Matou magma, which is different from the other porphyries in the belt. Our study

  7. The geological and metallogenic setting of stratabound carbonate-hosted Zn-Pb mineralizations in the West Asturian Leonese Zone, NW Spain

    Science.gov (United States)

    Tornos, F.; Ribera, F.; Shepherd, T. J.; Spiro, B.

    1996-01-01

    Several carbonate-hosted stratabound zinc-lead ores in the Ponferrada-Caurel area (NW Spain) are hosted by the Lower to Middle Cambrian Vegadeo Formation. Two clearly distinct groups of mineralizations occur in different stratigraphic positions. The stratiform disseminated ore is located in the Lower Member as irregular and millimetre-thick layers of sphalerite and galena replacing earlier pyrite. The lack of hydrothermal alteration and the heavy C., O and S isotopic signatures suggest that this ore is of premetamorphic origin, the sulphur and fluids being derived from the host carbonates. The more likely source of the sulphide is the abiogenic thermal reduction of sulphate derived from sulphate beds intercalated with the carbonates. The second group of mineralizations is located at the top of the Vegadeo Fm, always along its contact with the overlaying shales and sandstones of the Cabos Series. This group is economically more important and include three styles of strata-bound mineralizations. The more common one is the ‘silica ore’, a hydrothermal rock that traces the contact between the carbonate and the detrital rocks along more than 50 km. Locally, a ‘carbonate-rich ore’ is found along the contact between the silica ore and the Vegadeo Fm. Laterally to these rocks, there are large bodies of the ≪breccia ore≫, made up of sulphides and calcite in a matrix of chlorite. The ore assemblage is composed of sphalerite and galena with minor amounts of chalcopyrite and pyrite. Co-Ni-As sulphides, bismuthinite, tetrahedrite and Pb-Bi sulphosalts are also found as trace minerals. The geological relationships and the isotopic signatures suggest that the three ores are synchronous and of late Hercynian age. They are interpreted as linked with a tectonically driven fluid flow along the stratigraphic contact between the carbonate and the detrital rocks. The model of ore genesis involves the circulation of fluids in likely equilibrium with the detrital rocks that

  8. Alteration mineral mapping and metallogenic prediction using CASI/SASI airborne hyperspectral data in Mingshujing area of Gansu Province, NW China

    Science.gov (United States)

    Sun, Yu; Zhao, Yingjun; Qin, Kai; Tian, Feng

    2016-04-01

    Hyperspectral remote sensing is a frontier of remote sensing. Due to its advantage of integrated image with spectrum, it can realize objects identification, superior to objects classification of multispectral remote sensing. Taken the Mingshujing area in Gansu Province of China as an example, this study extracted the alteration minerals and thus to do metallogenic prediction using CASI/SASI airborne hyperspectral data. The Mingshujing area, located in Liuyuan region of Gansu Province, is dominated by middle Variscan granites and Indosinian granites, with well developed EW- and NE-trending faults. In July 2012, our project team obtained the CASI/SASI hyperspectral data of Liuyuan region by aerial flight. The CASI hyperspectral data have 32 bands and the SASI hyperspectral data have 88 bands, with spectral resolution of 15nm for both. The hyperspectral raw data were first preprocessed, including radiometric correction and geometric correction. We then conducted atmospheric correction using empirical line method based on synchronously measured ground spectra to obtain hyperspectral reflectance data. Spectral dimension of hyperspectral data was reduced by the minimum noise fraction transformation method, and then purity pixels were selected. After these steps, image endmember spectra were obtained. We used the endmember spectrum election method based on expert knowledge to analyze the image endmember spectra. Then, the mixture tuned matched filter (MTMF) mapping method was used to extract mineral information, including limonite, Al-rich sericite, Al-poor sericite and chlorite. Finally, the distribution of minerals in the Mingshujing area was mapped. According to the distribution of limonite and Al-rich sericite mapped by CASI/SASI hyperspectral data, we delineated five gold prospecting areas, and further conducted field verification in these areas. It is shown that there are significant gold mineralized anomalies in surface in the Baixianishan and Xitan prospecting

  9. Lateral structural variation along the Kalabagh Fault Zone, NW Himalayan foreland fold-and-thrust belt, Pakistan

    Science.gov (United States)

    Khan, Shuhab D.; Chen, Lize; Ahmad, Sajjad; Ahmad, Irshad; Ali, Fayaz

    2012-05-01

    The NW Himalayan fold-and-thrust belt in Pakistan is of gentler regional slope and wider extent than the other parts of the convergent plate boundary between India and the rest of Asia. Large scale structural re-entrants typify the Main Frontal Thrust (MFT) of the NW Himalayan fold-and-thrust belt in Pakistan. Understanding dynamics of the formation of these structural variations has been hampered by the lack of information about the lateral structures bounding the re-entrants. Our mapping of the Kalabagh Fault Zone, a lateral ramp linking the Salt and the Surghar Ranges, advanced spaceborne thermal emission and reflection radiometer (ASTER) data, field investigations and the interpreted reprocessed 2D seismic data. This integration of surface and subsurface geology provides new insights on the geometry and evolution of the Kalabagh Fault Zone, by showing that it forms an oblique ramp to the Main Frontal Thrust, and at north a lateral ramp with right-lateral strike slip movement. Our results indicate that the presence and areal extent of the evaporates is the dominant factor controlling lateral structural variation in the NW Himalayan fold-and-thrust belt of Pakistan. The Kalabagh Fault Zone acts as a zone that accommodates differential shortening and structural variation along the orogenic trend.

  10. Geological Fluid Mapping in the Tongling Area: Implications for the Paleozoic Submarine Hydrothermal System in the Middle-Lower Yangtze Metallogenic Belt, East China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Tongling area is one of the 7 ore-cluster areas in the Middle-Lower Yangtze metallogenic belt, East China, and has tectonically undergone a long-term geologic history from the late Paleozoic continental rifting, through the Middle Triassic continent-continent collision to the Jurassic-Cretaceous intracontinental tectono-magmatic activation. The Carboniferous sedimentary-exhalative processes in the area produced widespread massive sulfides with ages of 303-321 Ma, which partly formed massive pyrite-Cu deposits, but mostly provided significant sulfur and metals to the skarn Cu mineralization associated with the Yanshanian felsic intrusions.To understand the Carboniferous submarine hydrothermal system, an area of about 1046 km2 was chosen to carry out the geological fluid mapping. Associated with massive sulfide formation, footwall sequences 948 m to 1146 m thick, composed of the Lower Silurian-Upper Devonian sandstone, siltstone and thin-layered shale, were widely altered. This hydrothermal alteration is interpreted to reflect largescale hydrothermal fluid flow associated with the late Paleozoic crustal rifting and subsidence. Three hydrothermal alteration types, i.e., deep-level semiconformable silicification (S1), fracture-controlled quartz-sericite-pyrite alteration (S2-3), and upper-level sub-discordant quartz-sericite-chlorite alteration (D3), were developed to form distinct zones in the mapped area. About 50-m thick semiconformable siliclfication zones are located at ~1-km depth below massive sulfides and developed between an impermeable shale caprock (S1) and the underlying Ordovician unaltered limestone.Comparisons with modern geothermal systems suggest that the alteration zones record a sub-seafloor aquifer with the most productive hydrothermal fluid flow. Fracture-controlled quartz-sericite-pyrite alteration formed transgressive zones, which downward crosscut the semiconformable alteration zones,and upwards grade into sub-discordant alteration zones

  11. Gold Deposit Metallogenic Condition and Type Analysis in Manica Greenstone Belt, Mozambique%莫桑比克马尼卡绿岩带金矿成矿条件和类型分析

    Institute of Scientific and Technical Information of China (English)

    邓宇涛; 李胜利; 王松

    2015-01-01

    The gold producing area in Mozambique is situated in the Manica greenstone belt. It is a part of Manica-Mutare-Odzi (MMO) greenstone belt, from Odzi in eastern Zimbabwe through Mutare extend to Manica area in western Mozambique and make the ar-ea the most important gold deposit metallogenic belt in the country. The gold deposit is mainly enriched in a shear zone, banded iron-bearing formation of Archean mafic and ultramafic volcanic rocks or in faulted contact zone between supracrustal rocks and peripheral granite.%莫桑比克黄金产区位于马尼卡绿岩带,该绿岩带是马尼卡(Manica)-穆塔雷(Mutare)-奥德兹(Odzi)绿岩带的一部分,从津巴布韦东部奥德兹经过穆塔雷一直延伸到莫桑比克西部马尼卡地区,使马尼卡地区成为莫桑比克最重要的金矿成矿带.金矿主要富集在太古代镁铁质和超镁铁质火山岩中的剪切带、条带状含铁建造或在表壳岩与周边花岗岩之间的断裂接触带中.

  12. 青海东昆仑地区有色、贵金属矿床成矿系列%Study on the metallogenic series of nonferrous and precious metal deposits in eastern Kunlun orogenic belt, Qinghai

    Institute of Scientific and Technical Information of China (English)

    马顺清; 潘彤

    2012-01-01

    The eastern Kunlun metallogenic belt, located in Qinghai Province, is composed of northern Kunlun aulacogen belt, middle Kunlun granitic metamorphic complex belt and southern Kunlun composite merging zone, each with different geophysical and ge-ochemical characteristics. It passed through four tectonic evolution stages as followings; Late Proterozoic continental margin stage, Late Ordovician aulacogen stage, Late Paleozoic active multi- islands and sea continental margin stage and Middle - late Mesozoic back - arc amalgamation-and accretionary orogenesis stage. The mineralization is mainly formed in the Indonian and Caledonian periods, and outlined as three near EW - trending mineralization zones with different types of mineral deposits , and thus the metallogenetic series were formed by different tectonic evolution stages.%青海省东昆仑成矿带由昆北裂陷槽区、昆中花岗—变质杂岩带、昆南复合拼合带组成,各带形成了不同的地球物理、地球化学特征.其历经元古宙大陆边缘阶段,晚奥陶世裂陷槽阶段,晚古生代多岛洋活动大陆边缘阶段和中生代中—晚期弧后拼合—增生造山阶段4个构造演化阶段.成矿集中在印支期、加里东期,近东西向3条矿带形成不同类型矿产的分布.不同的演化阶段形成有色、贵金属矿成矿系列.

  13. Yanshanian Magma-Tectonic-Metallogenic Belt in East China of Circum-Pacific Domain (Ⅰ):Igneous Rocks and Orogenic Processes

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Yanshanian igneous rocks in the East China, on an orogenic belt scale, are characterized by the continental marginal arc in petrology and geochemistry as Andes and West USA, except for the Hercyn-type biotite-two mica-muscovite granite belt in the Nanling region. Three segments of the Yanshanian igneous rocks along the belt are recognized. In terms of magma-tectonic event sequence, the north, middle and south segments have counter-clockwise (ccw), clockwise (cw) and ccw+cw pTt paths of the orogenic process, respectively. A genetic model of the lithospheric delamination (loss of the lithospheric root in about 120 km) in combination with the oceanic subduction for the Yanshanian Andes-like orogenic belt and both the crust and lithosphere thickening for the Yanshanian Hercyn-type Nanling orogenic belt in the East China is suggested.

  14. The tectonic evolution of the Irtysh tectonic belt: New zircon U-Pb ages of arc-related and collisional granitoids in the Kalaxiangar tectonic belt, NW China

    Science.gov (United States)

    Hong, Tao; Klemd, Reiner; Gao, Jun; Xiang, Peng; Xu, Xing-Wang; You, Jun; Wang, Xin-Shui; Wu, Chu; Li, Hao; Ke, Qiang

    2017-02-01

    Precise geochronological constraints of the Irtysh tectonic belt situated between the Saur Island Arc and the Altay Terrane are crucial to a better understanding of the tectonic evolution of the Central Asian Orogenic Belt (CAOB). Recently, we discovered repeatedly deformed arc-related and collisional granitoids in the Kalaxiangar tectonic belt (KTB), which is located in the eastern part of the Irtysh tectonic belt. In this study, we report new whole-rock geochemical, zircon U-Pb and Hf isotopic data of the arc-related and collisional granitoids. Our data reveal that 1) arc-related granodioritic porphyries formed at ca. 382-374 Ma. Recrystallized zircon grains from a (ultra-)mylonitic granodiorite of the Laoshankou zone in the southern KTB display a U-Pb age of ca. 360 Ma; 2) syn-collisional granodioritic porphyries, which distribute along faults and parallel to the cleavage, were emplaced at ca. 367-356 Ma, with εHf(t) values varying from + 7.8 to + 14.2 and Hf model ages from 873 to 459 Ma; 3) a post-collisional A-type granodioritic porphyry, which crosscuts the NW-NNW trending schistosity of the metasedimentary country rocks at a low angle, has an age of ca. 324-320 Ma, while the εHf(t) values range from + 7.6 to + 14.4 with Hf model ages from 850 to 416 Ma; 4) post-collisional strike-slip A-type granite dykes, exposed along strike-slip faults, gave ages between 287 and 279 Ma, whereas the εHf(t) values range from + 4.9 to + 12.7 and the Hf model ages from 995 to 500 Ma; and 5) A-type biotite granite dykes, which intruded along conjugate tension joints, have ages of 274-271 Ma, and εHf(t) values from + 1.5 to + 13.2 with Hf model ages from 1196 to 454 Ma. Consequently, we propose that the collision between the Saur Island Arc and the Altay Terrane occurred in the Early Carboniferous (ca. 367-356 Ma) and the subsequent post-collisional tectonic process continued to the Late Carboniferous (ca. 324-320 Ma). It is further suggested that the Irtysh tectonic belt

  15. Mesozoic Granitic Magmatism and Molybdenum Ore-Forming Processes in the Xilamulun Metallogenic Belt%西拉沐伦成矿带中生代花岗岩浆活动与钼成矿作用

    Institute of Scientific and Technical Information of China (English)

    曾庆栋; 周伶俐; 段晓侠; 张松; 王永彬; 刘建明; 褚少雄; 付国立; 于文斌; 李泽明; 高玉友; 李元九; 孙燕

    2011-01-01

    位于华北克拉通北缘的西拉沐伦成矿带内花岗岩浆活动及钼矿化发育,带内主要成矿侵入体岩石类型包括二长花岗岩、斑状花岗岩、花岗斑岩及流纹斑岩,这些岩石属于高钾钙碱性和钾玄岩系列,岩浆源区为古老下地壳和新生地壳.这些侵入体形成于早—中三叠世、晚侏罗世及早白垩世.带内钼矿床包括斑岩型、石英脉型、云英岩型和火山-次火山热液型4种类型,以斑岩型矿床最为发育.带内钼矿床形成时代与相关侵入岩时代一致,也形成于早—中三叠世、晚侏罗世及早白垩世,以早白垩世钼矿床最为发育.3期成岩成矿作用分别形成于华北板块与西伯利亚板块同碰撞至后碰撞构造环境、古太平洋板块向欧亚大陆俯冲的构造环境和中国东部岩石圈减薄构造环境.%Granitoids and molybdenum ore deposits or ore spots are well developed in the Xilamulun metallogenic belt located on the northern margin of the North China craton. The ore-bearing intrusive rocks include monozogranite, porphyritic granite, granite porphyry and rhyolite porphyry, which belong to the high-K calc-alkaline and shoshonite series. The rock-forming materials were derived from the lower crust and juvenile crust. These granitic intrusive rocks were formed in Early Middle Triassic, Late Jurassic and Early Cretaceous. The molybdenum deposits are of porphyry, quartz vein, greisen and volcanic-subvolcanic hydrothermal types. The ore-forming ages of the molybdenum deposits are consistent with the ages of the intrusive rocks and can be divided into three stages, I. E. , Early-Middle Triassic, Late Jurassic and Early Cretaceous. The Early Cretaceous porphyry molybdenum deposits areTsav, Jiawula, Chaganbulagen Ag-Pb-Zn deposits as well as Errentaolegai Ag deposit are located at northeastern part of the Northern China- Mongolia block (NCMB), and constitute the most important Ag-polymetalic ore cluster along the China

  16. CRED REA Fish Team Belt Transect Survey at French Frigate Shoals, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 10 sites at French Frigate Shoals...

  17. Discovery of Cu-Zn, Cu-Sn intermetallic minerals and its significance for genesis of the Mianning-Dechang REE Metallogenic Belt, Sichuan Province, China

    Institute of Scientific and Technical Information of China (English)

    XIE Yuling; HOU Zengqian; XU Jiuhua; YUAN Zhongxin; BAI Ge; LI Xiaoyu

    2006-01-01

    Mianning-Dechang Himalayan REE Metallogenetic Belt in Sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2Zn), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

  18. Research on Superimposed Metallogenic System

    Institute of Scientific and Technical Information of China (English)

    Zhai Yusheng; Wang Jianping; Deng Jun; Peng Runmin

    2004-01-01

    As located in the junction of three tectonic plates (the Eurasian plate, the Indian plate and the west Pacific plate), the China continent shows complex regional metallogenic features due to tectonic evolution of "micro-plates, polycycle tectonic movements". Well developed superimposed metallogenic systems have constituted one of the regional metallogenic features in China. Through the study on superimposed metallogenic system of the middle and lower reaches of the Yangtze River and of the Yuebei basin (northern Guangdong Province), the authors put forward some basic combination pattern of sedimentary-magmatic superimposed metallogenic system and summarize its forming conditions (controlling factors).

  19. Analysis on tectonomagmatic evolution and metallogenic geological conditions of rich-large uranium deposits in Nanling uranium-polymetal metallogenic belt, South Jiangxi province%南岭铀多金属成矿带赣南段构造-岩浆演化及富大铀矿成矿条件分析

    Institute of Scientific and Technical Information of China (English)

    陈贵华; 陈培荣; 杨卫明

    2001-01-01

    南岭是一条复杂的构造-岩浆活动带,也是我国重要的铀多金属成矿带。作者在前人丰硕研究成果的基础上,通过地层清理及断代划分,岩性、岩相古地理研究,岩石的年代学及地球化学研究,重磁资料的深层次处理和遥感深层次信息的提取,得出了如下认识:(1)三南-寻乌断裂是一条从早震旦至现代长期活动的东西向深断裂带;(2)南岭地区地壳经历3次不同规模的南北向开合活动;(3)安远-寻乌地区为一大型热隆伸展构造;(4)初步认为该区具备形成富大铀矿的条件。%Nanling is a complicated tectonomagmatic belt. It is also an important uranium-polymetallic metallogenic belt. On the basis of the research achievements of previous researchers, through the detailed stratigraphyic, lithologic, litho-paleogeographic, geochronologic and geochemical studies and the processing of gravimetric and magnetic data, as well as the information extraction of remote sensing data, the authors come to the following conclusions:(1)The Sannan-Xunwu fault is a long-lived(from the Early Sinian to recent time)EW-trending fault;(2)The earth crust in Nanling experienced three time opening-closing with different scales;(3)The Anyuan-Xunwu area is a large thermo-upwelling extensional structure;(4)The above area is considered to be favourable for the formation of rich-large uranium deposit.

  20. Evolution of the Cretaceous magmatism in the Apuseni-Timok-Srednogorie metallogenic belt and implications for the geodynamic reconstructions: new insight from geochronology, geochemistry and isotope studies

    Science.gov (United States)

    von Quadt, A.; Peytcheva, I.; Heinrich, C. A.; Frank, M.; Cvetkovic, V.

    2003-04-01

    Most major Cu-Au (-PGE) deposits in the Carpathian Balkan orogen are related to a 1500 km long belt of Upper Cretaceous magmatism extending from southern Romania through Yugoslavia to Bulgaria, with a likely continuation southeast of the Black Sea into Turkey, known as the Apuseni Banat Timok Srednogorie (ABTS) belt (Popov et al., 2000). In the frame of ABTS belt a new investigation was started to reveal the relation between Cretaceous magmatism and the Cu-Au-PGE deposits across the belt in East Serbia (Yugoslavia) and the Panagyurishte district (Bulgaria). The Late Cretaceous (Palaeogene?) magmatism of East Serbia developed along the Timok Magmatic Complex (TMC) in the east and the Ridanj Krepoljin Zone (RKZ) in the west. High precision U-Pb single zircon dating and a combination of isotope tracing, geochronological data as well as petrological data were used to provide additional data for the geodynamic evolution. A maximum life span of 2.5 Ma could be calculated for the first phase of volcanic activity in TMC, starting with the Amf-andesites of Veliki Kravelj (86.29 ± 0.32 Ma) and finishing with the Timozites (84.66 ± 0.5 Ma). Ore bearing magmatism in a single deposit (Veliki Kravelj) extended a maximum of 0.6 Ma ("pre-ore": 86.29 ± 0.32 Ma, "post-ore": 86.17 ± 0.15 Ma). Preliminary data for the dacites (70.3 ± 3.5 Ma) outcropping near Krepoljin give evidence for a shifting of the volcanic activity from TMC to RKZ together with changing the ore-deposit type from Cu-Au-PGE (TMC) to Pb-Zn-Cu (RKZ). Isotope tracing give evidence for mantle dominated source with increasing of crustal contamination in the same direction: (87Sr/86Sr ratios: 0.70388 to 0.706050, e-Hf-zircon data: +12 in TMC to +4.5 in RKZ). The Panagyurishte district (Bulgaria) show a duration time of the magmatic activity of 14 Ma, starting in the north at 92 Ma and finishing in the south at 78 Ma. Ore-related magmatism becomes younger in the same direction but finishes with 86 Ma. Multiple short

  1. U-Pb, Re-Os, and 40Ar/39Ar geochronology of the Nambija Au-skarn and Pangui porphyry Cu deposits, Ecuador: implications for the Jurassic metallogenic belt of the Northern Andes

    Science.gov (United States)

    Chiaradia, Massimo; Vallance, Jean; Fontboté, Lluis; Stein, Holly; Schaltegger, Urs; Coder, Joshua; Richards, Jeremy; Villeneuve, Mike; Gendall, Ian

    2009-05-01

    New U-Pb, Re-Os, and 40Ar/39Ar dates are presented for magmatic and hydrothermal mineral phases in skarn- and porphyry-related ores from the Nambija and Pangui districts of the Subandean zone, southeastern Ecuador. Nambija has been one of the main gold-producing centers of Ecuador since the 1980s due to exceptionally high-grade ores (average 15 g/t, but frequently up to 300 g/t Au). Pangui is a recently discovered porphyry Cu-Mo district. The geology of the Subandean zone in southeastern Ecuador is dominated by the I-type, subduction-related, Jurassic Zamora batholith, which intrudes Triassic volcanosedimentary rocks. The Zamora batholith is in turn cut by porphyritic stocks, which are commonly associated with skarn formation and/or porphyry-style mineralization. High precision U-Pb and Re-Os ages for porphyritic stocks (U-Pb, zircon), associated prograde skarn (U-Pb, hydrothermal titanite), and retrograde stage skarn (Re-Os, molybdenite from veins postdating gold deposition) of the Nambija district are all indistinguishable from each other within error (145 Ma) and indicate a Late Jurassic age for the gold mineralization. Previously, gold mineralization at Nambija was considered to be Early Tertiary based on K-Ar ages obtained on various hydrothermal minerals. The new Jurassic age for the Nambija district is slightly younger than the 40Ar/39Ar and Re-Os ages for magmatic-hydrothermal minerals from the Pangui district, which range between 157 and 152 Ma. Mineralization at Nambija and Pangui is associated with porphyritic stocks that represent the last known episodes of a long-lived Jurassic arc magmatism (˜190 to 145 Ma). A Jurassic age for mineralization at Nambija and Pangui suggests that the Northern Andean Jurassic metallogenic belt, which starts in Colombia at 3° N, extends down to 5° S in Ecuador. It also adds a new mineralization style (Au-skarn) to the metal endowment of this belt.

  2. Age, tectonic setting, and metallogenic implication of Phanerozoic granitic magmatism at the eastern margin of the Xing'an-Mongolian Orogenic Belt, NE China

    Science.gov (United States)

    Chen, Cong; Ren, Yunsheng; Zhao, Hualei; Yang, Qun; Shang, Qingqing

    2017-08-01

    The eastern margin of the Xing'an-Mongolian Orogenic Belt is characterised by widespread Phanerozoic granitic magmatism, some of which is closely related to significant ore mineralisation. This paper presents new geochronological, petrogenetic, and tectonic data for selected intrusions. Zircon U-Pb geochronology for five granitoid plutons indicates they were emplaced during the middle-late Permian (264-255 Ma) and Cretaceous (106-94 Ma), and thus granitic magmatism occurred throughout the Phanerozoic, Permian (268-252 Ma), Early-Middle Triassic (248-240 Ma), Early Jurassic (183 Ma), and Cretaceous (112-94 Ma). The Permian granitoids consist of monzogranite, granodiorite, tonalite, and quartz diorite, characterised by enrichment in Na2O (3.60-4.72 wt.%), depletion in K2O (0.97-2.66 wt.%), and a negative correlation between P2O5 and SiO2. Together with the presence of hornblende, these geochemical features are indicative of an I-type affinity. The Permian granitic magmatism is associated with quartz-vein-type tungsten deposits (252 Ma; unpublished Sm-Nd isochron age), which formed in an active continental margin setting related to subduction of the Palaeo-Asian Ocean. The Cretaceous quartz diorites have an adakitic affinity, having relatively high Sr (374-502 ppm), low Yb (0.51-0.67 ppm) and Y (8.7-10.7 ppm), and high Sr/Y (39.4-46.8) and (La/Yb)N values (16.2-34.7), suggesting that they were related to the partial melting of subducted oceanic crust. In addition, they are associated with porphyry Au-Cu deposits. We conclude that the Cretaceous granitic rocks and associated porphyry Au-Cu mineralisation occurred in an extensional tectonic setting related to the subduction of the Palaeo-Pacific Plate beneath the Eurasian Plate. In addition, the large-scale Early-Middle Triassic syn-collisional granite belt at the eastern margin of the Xing'an-Mongolian Orogenic Belt extends from the middle of Jilin Province to the Wangqing-Hunchun region, constraining the timing of the

  3. Multistage gold mineralization in the Wa-Lawra greenstone belt, NW Ghana: The Bepkong deposit

    Science.gov (United States)

    Amponsah, Prince Ofori; Salvi, Stefano; Didier, Béziat; Baratoux, Lenka; Siebenaller, Luc; Jessell, Mark; Nude, Prosper Mackenzie; Gyawu, Eugene Adubofour

    2016-08-01

    The Bepkong gold deposit is one of several gold camps in the Paleoproterozoic Wa-Lawra greenstone belt in northwest Ghana. These deposits lay along the Kunche-Atikpi shear zone, which is part of the larger transcurrent Jirapa shear zone. The formation of these shear zones can be attributed to the general ESE-WNW major shortening that took place in the Wa-Lawra belt. Gold mineralization in the Bepkong deposit mainly occurs within graphitic shales and volcaniclastic rocks. The ore consists of four N-S trending lenticular bodies, plunging steeply to the south, that are lithologically and structurally controlled. Their shape and thickness are variable, though a general strike length of 560 m and an overall thickness of 300 m can be defined. An alteration mineral assemblage characterises the ore, and consists of chlorite-calcite-sericite-quartz-arsenopyrite-pyrite. Pyrite, as distinct from arsenopyrite, is not limited to the altered rocks and occurs throughout the area. At Bepkong, gold is associated with arsenopyrite and pyrite, which occur disseminated in the mineralized wall rock, flanking Type-1 quartz veins, or within fractures crossing these veins. Textural observations indicate the early formation of abundant arsenopyrite, followed by pyrite, with chalcopyrite, galena, sphalerite and pyrrhotite occurring as inclusions within pyrite and altered arsenopyrite. Detailed petrography, coupled with SEM, LA-ICP-MS and EMP analyses, indicate that gold in the Bepkong deposit occurs in three distinct forms: (i) invisible gold, mostly in arsenopyrite (ii); visible gold as micron-size grains within fractures and altered rims of arsenopyrite, as well as at the interface of sulphide grains; (iii) free visible gold in fractures in quartz veins and their selvages. We interpret the invisible gold to have co-precipitated with the early-formed arsenopyrite. The small visible gold grains observed within the sulphide interfaces, altered arsenopyrite, fractures and grain boundaries

  4. Resources evaluation of layer-shaped volcanic lava-type uranium deposits in Dazhou ore-field,Gan-Hang uranium metallogenic belt%赣杭铀成矿带大洲矿田层状火山熔岩型铀矿资源评价

    Institute of Scientific and Technical Information of China (English)

    毛孟才

    2001-01-01

    本文全面总结了大洲铀矿田成矿地质背景及铀矿特征,分析了溶浸采矿条件,论述了大洲铀矿田溶浸采矿的可行性,并指明应用溶浸采矿技术重新评价赣杭铀成矿带硬岩型铀矿资源的必要性。%According to the technological requirements, using theory ofsolution mining, the author makes a resources evaluation of layer-shaped volcanic lava-type uranium deposits in Dazhou ore-field, Gan-Hang uranium metallogenic belt. This paper comprehensively summarizes the metallogenic geologic background and characteristics of uranium deposits in Dazhou uranium ore-field, analyses the conditions of solution mining and describes the feasibility of solution mining in Dazhou uranium ore-field, then proposes the necessity to reevaluate hard rock uranium resources in Gan-Hang uranium metallognic belt.

  5. Petrogenesis of Late Mesozoic granitoids and coeval mafic rocks from the Jiurui district in the Middle-Lower Yangtze metallogenic belt of Eastern China: Geochemical and Sr-Nd-Pb-Hf isotopic evidence

    Science.gov (United States)

    Xu, Yao-Ming; Jiang, Shao-Yong; Zhu, Zhi-Yong; Yang, Shui-Yuan; Zhou, Wei

    2014-03-01

    enriched lithospheric mantle. The thickened lower continental crust and underlying enriched lithospheric mantle may have been simultaneously delaminated into the asthenospheric mantle. This process led to the partial melting of the thickened lower crust and the enriched lithospheric mantle, and the melts experienced an interaction with the asthenospheric mantle during ascension. Mafic melts could be generated from the enriched lithospheric mantle, which was heated by the upwelling asthenospheric mantle. The geochemical and isotopic compositions of mafic rocks were most likely controlled by the AFC process. A geochemical and isotopic comparison of the granitoids in the Jiurui district with those of two other districts (e.g., Angui and Tongling) in the same mineralization belt indicates that a significant crust-mantle interaction played a crucial role in their petrogeneses and metallogeneses. From the southwest to northeast in this metallogenic belt, the proportion of mantle component that was involved in the granitic magma shows a decreasing trend from the Jiurui to the Angui and Tongling districts. It is suggested that the Juirui district has the highest potential for a significant amount of Cu-Au accumulation because the mantle is an important supply for these metals.

  6. Discovery and Genetic Mechanism of Basic Granulite in the Altay Orogenic Belt, Xinjiang, NW China

    Institute of Scientific and Technical Information of China (English)

    LI Zilong; CHEN Hanlin; YANG Shufeng; DONG Chuanwan; XIAO Wenjiao; LI Jiliang; YE Ying; WANG Jian

    2004-01-01

    Altay granulite (AG), which represents the product of high-grade metamorphism in the lower crust, was newly found in thc Wuqiagou area, Fuyun County in the Altay orogenic belt, Northwest China. It is composed mainly of hypersthene, augite, basic plagioclase, amphibole and brown biotite. Its mineral compositions of amphibole and biotite are rich in Mg/(Mg+Fe2+) and Ti. Geochemically, the AG is enriched in Mg/(Mg+Fe2+) and A12O3, and poor in CaO, with depletion of U, Th, K and Rb contents. Furthermore, geochemical data reflect that the protolith of the AG is igneousgenetic calc-alkalinc basalt formed under an island arc environment. The AG has ∑REE of 92.38-96.58 ppm and enriched LREE model with weak positive Eu anomaly of 1.09-1.15. In the MORB normalized spider diagram, the AG shows tridoming pattern with a strong negative Nb anomaly and medium negative P and Ti anomalies, reflecting that the AG has tectonic relation with subduction or subduction-related materials. The P-Tconditions of peak metamorphism of the AG arc 750-780°C and >0.6-0.7 GPa. Retrograde metamorphism implies that the protolith of the Altay granulite might undergo a metamorphic process along a clockwise P-T trajectory. Thereforc, thc formation and evolution of thc AG may have a genetic association with continental collision/orogeny and the AG was taken into the Late Paleozoic meta-strata by way of tectonic emplacement.

  7. Geochemical characteristics of the Shujiadian Cu deposit related intrusion in Tongling: Petrogenesis and implications for the formation of porphyry Cu systems in the Middle-Lower Yangtze River Valley metallogenic belt, eastern China

    Science.gov (United States)

    Wang, Shiwei; Zhou, Taofa; Yuan, Feng; Fan, Yu; Cooke, David R.; Zhang, Lejun; Fu, Bin; White, Noel C.

    2016-05-01

    Porphyry Cu deposits can form in intracontinental or post-collision settings; however, both the genesis of fertile magmas and the mechanism of metal enrichment remain controversial. The Shujiadian porphyry Cu deposit is located in the Tongling area of the Middle-Lower Yangtze River Valley metallogenic belt. It is hosted by the Shujiadian complex, which mainly consists of quartz diorite porphyry (143.7 ± 1.7 Ma) and pyroxene diorite (139.8 ± 1.6 Ma). They both belong to the calc-alkaline series, with enrichment in large-ion lithophile elements (LILE) and light rare earth elements (LREE), depletion in high field-strength elements (HFSE) and heavy rare earth elements (HREE), and slightly negative Eu anomalies. Both quartz diorite porphyry and pyroxene diorite have geochemical affinities with adakite, and their low MgO (1.5-3.7 wt%), and Ni (3.7-6.9 ppm), Cr (2.0-44 ppm), and Th/Ce contents (0.06-0.11) indicate that the intrusive rocks have some characteristics of adakite-like rocks derived from thickened lower crust and melts from metabasaltic rocks and eclogites. Plagioclases from the quartz diorite porphyry are andesine (An value = 31.8-40.5) and from the pyroxene diorite are felsic albite and oligoclase with large-scale zones and variable An value (An value = 8.9-18.3), Fe and Sr contents, which indicate that mixing of mafic and felsic magma may have occurred in the shallow magma chamber. Compared to the barren quartz diorite porphyry, relatively lower SiO2 contents (49.5-55.2 wt.%), higher εNd(t) values (- 7.4 to - 6.9), εHf(t) values (- 11.0 to - 9.1) compositions, Ti-in-zircon temperatures (714-785 °C), and variations of HREE contents of the mineralization-related pyroxene diorite suggest mixing with high-temperature mafic magma. Calculated Ce4 +/Ce3 + values of pyroxene diorite plot between the Ni-NiO buffer (NNO) and magnetite-hematite buffer (MH), and barren quartz diorite porphyry samples plot below the Ni-NiO buffer (NNO). Geochemical features of

  8. Paleozoic magmatism and porphyry Cu-mineralization in an evolving tectonic setting in the North Qilian Orogenic Belt, NW China

    Science.gov (United States)

    Qiu, Kun-Feng; Deng, Jun; Taylor, Ryan D.; Song, Kai-Rui; Song, Yao-Hui; Li, Quan-Zhong; Goldfarb, Richard J.

    2016-01-01

    The NWW-striking North Qilian Orogenic Belt records the Paleozoic accretion–collision processes in NW China, and hosts Paleozoic Cu–Pb–Zn mineralization that was temporally and spatially related to the closure of the Paleo Qilian-Qinling Ocean. The Wangdian Cu deposit is located in the eastern part of the North Qilian Orogenic Belt, NW China. Copper mineralization is spatially associated with an altered early Paleozoic porphyritic granodiorite, which intruded tonalites and volcaniclastic rocks. Alteration zones surrounding the mineralization progress outward from a potassic to a feldspar-destructive phyllic assemblage. Mineralization consists mainly of quartz-sulfide stockworks and disseminated sulfides, with ore minerals chalcopyrite, pyrite, molybdenite, and minor galena and sphalerite. Gangue minerals include quartz, orthoclase, biotite, sericite, and K-feldspar. Zircon LA-ICPMS U–Pb dating of the ore-bearing porphyritic granodiorite yielded a mean 206Pb/238U age of 444.6 ± 7.8 Ma, with a group of inherited zircons yielding a mean U–Pb age of 485 ± 12 Ma, consistent with the emplacement age (485.3 ± 6.2 Ma) of the barren precursor tonalite. Rhenium and osmium analyses of molybdenite grains returned model ages of 442.9 ± 6.8 Ma and 443.3 ± 6.2 Ma, indicating mineralization was coeval with the emplacement of the host porphyritic granodiorite. Rhenium concentrations in molybdenite (208.9–213.2 ppm) suggest a mantle Re source. The tonalities are medium-K calc-alkaline. They are characterized by enrichment of light rare-earth elements (LREEs) and large-ion lithophile elements (LILEs), depletion of heavy rare-earth elements (HREEs) and high-field-strength elements (HFSEs), and minor negative Eu anomalies. They have εHf(t) values in the range of +3.6 to +11.1, with two-stage Hf model ages of 0.67–1.13 Ga, suggesting that the ca. 485 Ma barren tonalites were products of arc magmatism incorporating melts from the mantle wedge and

  9. Chronology and origin of VMS deposits in Xinjiang, NW CHINA

    Institute of Scientific and Technical Information of China (English)

    CHEN; Fuwen(陈富文); LI; Huaqin(李华芹); WANG; Denghong(王登红); XIE; Caifu(谢才富); LU; Yuanfa(路远发)

    2002-01-01

    VMS deposits in Xinjiang, NW China are widespread in the Altay, Tianshan and West Kunlun orogenic belt, mainly formed during the Proterozoic rifting and Phanerozoic post-orogenic extension and are related to the bimodal volcanism. The VMS deposits are middle and small in scale. According to assemblages of metallogenetic elements, they can be divided into four types (Cu-Zn, Cu-S, Pb-Zn-Cu and Pb-Zn types) with the Cu-Zn and Pb-Zn types being the most important ones. Research of isotopic chronology shows that the VMS deposits in Xinjiang were formed during the Proterozoic, Ordovician, Deovonian, Carboniferous and Permian periods and usually underwent multi-stage mineralization, especially the large-sized deposits usually have post- volcanic superimposed mineralization by tectonomagmatic or metamorphic hydrothermal metallogenic fluids.

  10. Geological characteristics and clues for prospecting of Weishancheng Au-Ag metallogenic belt in Tongbo of Henan%河南桐柏围山城金、银成矿带矿床地质特征及找矿标志

    Institute of Scientific and Technical Information of China (English)

    徐春林

    2014-01-01

    Weishancheng Au-Ag metallogenic belt deposit is located at north subzone of Tongbo-Dabieshan (north slope)Au-Ag metallogenic belt.The orebodies mainly occur in carbon-bearing sericitic quartz schist of Epiproterozoic Waitoushan groups and it is under strict control of tectonic setting.The ore-bearing forma-tion is affected by hydrothermal fluid and generates different alteration,while mineralization is closely relat-ed to silicification.The mining area has favorable mineral-formation conditions and abundant resource.Based on the detailed analysis of formations,rocks,structure and wall rock alteration in the mining area,the au-thor proposes clues for prospecting.%围山城金银成矿带矿床位于桐柏-大别山(北坡)金银成矿带北亚带。矿体主要赋存于上元古界歪头山组炭质绢云石英片岩内,严格受构造条件控制,含矿层受热液作用影响产生不同蚀变,尤其硅化与矿化的关系最为密切。矿区成矿地质条件优越,资源丰富。笔者在对矿带内地层、岩石、构造、围岩蚀变等较为详细分析的基础上提出了找矿标志。

  11. Science Letters: Discovery of ultrahigh-T spinel-garnet granulite with pure CO2 fluid inclusions from the Altay orogenic belt, NW China

    Institute of Scientific and Technical Information of China (English)

    厉子龙; 陈汉林; SANTOSHM.; 杨树锋

    2004-01-01

    We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the orthopyroxenes have high XMg and Al2O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around -56.7℃, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3-23.8℃ translating into CO2 densities of the order of 0.86-0.88g/cm3. Based on preliminary mineral paragenesis, reaction textures and petrogenetic grid considerations, we infer that the rock was subjected to UHT conditions. The CO2-rich fluids were trapped during exhumation along a clockwise P-T path following isothermal decompression under UHT conditions.

  12. Discovery of ultrahigh-T spinel-garnet granulite with pure CO2 fluid inclusions from the Altay orogenic belt, NW China.

    Science.gov (United States)

    Li, Zi-long; Chen, Han-lin; Santosh, M; Yang, Shu-feng

    2004-10-01

    We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the orthopyroxenes have high XMg and Al2O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around -56.7 degrees C, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3-23.8 degrees C translating into CO2 densities of the order of 0.86-0.88 g/cm3. Based on preliminary mineral paragenesis, reaction textures and petrogenetic grid considerations, we infer that the rock was subjected to UHT conditions. The CO2-rich fluids were trapped during exhumation along a clockwise P-T path following isothermal decompression under UHT conditions.

  13. Discovery of ultrahigh-T spinel-garnet granulite with pure CO2fluid inclusions from the Altay orogenic belt, NW China*

    Science.gov (United States)

    Li, Zi-long; Chen, Han-lin; Santosh, M; Yang, Shu-feng

    2004-01-01

    We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the orthopyroxenes have high XMg and Al2O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around −56.7 °C, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3–23.8 °C translating into CO2 densities of the order of 0.86–0.88 g/cm3. Based on preliminary mineral paragenesis, reaction textures and petrogenetic grid considerations, we infer that the rock was subjected to UHT conditions. The CO2-rich fluids were trapped during exhumation along a clockwise P-T path following isothermal decompression under UHT conditions. PMID:15362187

  14. Discovery of ultrahigh-T spinel-garnet granulite with pure CO2 fluid inclusions from the Altay orogenic belt, NW China

    Institute of Scientific and Technical Information of China (English)

    LI Zi-long (厉子龙); CHEN Han-lin (陈汉林); SANTOSH M.; YANG Shu-feng (杨树锋)

    2004-01-01

    We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel,and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the orthopyroxenes have high XMg and Al2O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around -56.7 ℃, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3-23.8℃ translating into CO2densities of the order of 0.86-0.88 g/cm3. Based on preliminary mineral paragenesis, reaction textures and petrogenetic grid considerations, we infer that the rock was subjected to UHT conditions. The CO2-rich fluids were trapped during exhumation along a clockwise P-T path following isothermal decompression under UHT conditions.

  15. Seismic profile analysis of the Kangra and Dehradun re-entrant of NW Himalayan Foreland thrust belt, India: A new approach to delineate subsurface geometry

    Indian Academy of Sciences (India)

    Joyjit Dey; R Jayangonda Perumal; Subham Sarkar; Anamitra Bhowmik

    2017-08-01

    In the NW Sub-Himalayan frontal thrust belt in India, seismic interpretation of subsurface geometry of the Kangra and Dehradun re-entrant mismatch with the previously proposed models. These procedures lack direct quantitative measurement on the seismic profile required for subsurface structural architecture. Here we use a predictive angular function for establishing quantitative geometric relationships between fault and fold shapes with ‘Distance–displacement method’ (D–d method). It is a prognostic straightforward mechanism to probe the possible structural network from a seismic profile. Two seismic profiles Kangra-2 and Kangra-4 of Kangra re-entrant, Himachal Pradesh (India), are investigated for the fault-related folds associated with the Balh and Paror anticlines. For Paror anticline, the final cut-off angle β=35∘ was obtained by transforming the seismic time profile into depth profile to corroborate the interpreted structures. Also, the estimated shortening along the Jawalamukhi Thrust and Jhor Fault, lying between the Himalayan Frontal Thrust (HFT) and the Main Boundary Thrust (MBT) in the frontal fold-thrust belt, were found to be 6.06 and 0.25 km, respectively. Lastly, the geometric method of fold-fault relationship has been exercised to document the existence of a fault-bend fold above the Himalayan Frontal Thrust (HFT). Measurement of shortening along the fault plane is employed as an ancillary tool to prove the multi-bending geometry of the blind thrust of the Dehradun re-entrant.

  16. 亚欧东西向活化构造铀成矿带划分依据及铀成矿域分布%The Division Basis of the Eurasian EW Strike Reactivated Tectonic Uranium Metallogenic Belt and Distribution of Uranium Provinces

    Institute of Scientific and Technical Information of China (English)

    姚振凯; 刘翔; 郑大瑜

    2014-01-01

    亚欧东西向活化构造铀成矿带,其铀资源量约为全球的50%,是全球最重要的大陆洲际铀成矿带。该带地质构造和成矿复杂,活化构造作用延续时间最长,从早元古宙至今断续发生活化作用,以中新生代活化最为强烈。文章从大地构造及其演化控矿的角度,以铀成矿域为单元,对划分该铀成矿带的大地构造、深部构造、地球物理、地球化学和铀成矿分布等依据及铀成矿域分布作初步论述。%Over half of the global uranium resources occurred along the east-west activated Eurasian tectonic belt which is the most important in the world.The geological structure and uranium mineralization are complicated in the belt.From early Proterozoic ,the tectonic activity occurred intermittently ,Especially in the Mesozoic and Ce-nozoic period , the activity were the most strongest.In this paper , the basis of the geotectology , deep-crustal stracture ,geophysic-geochimistry and distribution of uranium mineralization were discussed for the division of the reactivated tectonic uranium metallogenic belt and the distribution of uranium mineralization provinces from the views of geotectonics and evolution ore controlling.

  17. Tectonic evolution of the Irtysh collision belt: New zircon U-Pb ages of deformed and collisional granitoids in the Kalaxiangar area, NW China

    Science.gov (United States)

    Tao, Hong; Jun, Gao; Xingwang, Xu; Klemd, Reiner

    2016-04-01

    The CAOB is thought to have formed by multiple accretion and collision of various microcontinents, island arcs, oceanic plateaus and accretionary wedges due to the closure of the Paleo-Asia Ocean [1, 2, 3]. The Irtysh collision belt is located at the middle-western part of the CAOB and generally thought to be the result of the collision of the Sawuer Island arc and the Altay Terrane, subsequent to the consumption of the Early Paleozoic Junggar Ocean, a branch of Paleo-Asia Ocean. Therefore, the exact timing of the Irtysh collision belt is crucial for a better understanding of the tectonic evolution of this collision belt and will provide constraints on the evolution of the CAOB. Recently, we discovered various collisional granitoids in the Kalaxiangar tectonic belt (KTB), which is located in the eastern part of the Irtysh collision belt. In this contribution, we report new geochemical whole-rock, zircon U-Pb and Hf isotopic data of the arc-related and collisional granitoids. Our new results reveal that 1) the arc-related granodioritic porphyries formed at ca. 374 Ma. Furthermore, recrystallized zircons from the granodioritic mylonite and ultramylonite of the Laoshankou ductile deformation zone have a similar U-Pb age of ca. 360 Ma; 2) the syn-collisional granodioritic porphyries, which distribute along cleavege, were emplaced at ca. 355 Ma; 3) the post-collisional A-type granodioritic porphyry, which cuts the NW-NNW trending schistosity at a low angle, has an age of ca. 323 Ma, ɛHf(t) values from + 7.5 to + 14.4, and young Hf model ages between 387 and 658 Ma; 4) the post-collisional A-type granite dykes, which are exposed along strike-slip faults, have ages between 282.5 and 279.2Ma, ɛHf(t) values from + 4.8 to + 12.6, and Hf model ages between 436 and 729 Ma; 5) the A-type biotite granite dykes that intruded along conjugate tension joints have ages between 273.9 and 271.4 Ma, ɛHf(t) values from + 1.1 to + 12.8, and Hf model ages between 393 and 979 Ma. In

  18. Paleozoic intrusive rocks from the Dunhuang tectonic belt, NW China: Constraints on the tectonic evolution of the southernmost Central Asian Orogenic Belt

    Science.gov (United States)

    Zhao, Yan; Sun, Yong; Diwu, Chunrong; Zhu, Tao; Ao, Wenhao; Zhang, Hong; Yan, Jianghao

    2017-05-01

    The Dunhuang tectonic belt (DTB) is of great importance for understanding the tectonic evolution of the southernmost Central Asian Orogenic Belt (CAOB). In this study, the temporal-spatial distribution, petrogenesis and tectonic setting of the Paleozoic representative intrusive rocks from the DTB were systematically investigated to discuss crustal evolution history and tectonic regime of the DTB during Paleozoic. Our results reveal that the Paleozoic magmatism within the DTB can be broadly divided into two distinct episodes of early Paleozoic and late Paleozoic. The early Paleozoic intrusive rocks, represented by a suite metaluminous-slight peraluminous and medium- to high-K calc-alkaline I-type granitoids crystallized at Silurian (ca. 430-410 Ma), are predominantly distributed along the northern part of the DTB. They were probably produced with mineral assemblage of eclogite or garnet + amphibole + rutile in the residue, and were derived from magma mixing source of depleted mantle materials with various proportions of Archean-Mesoproterozoic continental crust. The late Paleozoic intrusive rocks can be further subdivided into two stages of late Devonian stage (ca. 370-360 Ma) and middle Carboniferous stage (ca. 335-315 Ma). The former stage is predominated by metaluminous to slight peraluminous and low-K tholeiite to high-K calc-alkaline I-type granitic rocks distributed in the central part of the DTB. They were also generated with mineral assemblage of amphibolite- to eclogite-facies in the residue, and originated from magma source of depleted mantle materials mixed with different degrees of old continental crust. The later stage is represented by adakite and alkali-rich granite exposed in the southern part of the DTB. The alkali-rich granites studied in this paper were possibly produced with mineral assemblage of granulite-facies in the residue and were generated by partial melting of thickened lower continental crust. Zircon Hf isotopes and field distribution of

  19. Ore-forming fluid geochemistry of Yangchang quartz vein molybdenum deposit in Xilamulun molybdenum metallogenic belt, Inner Mongolia%内蒙古西拉沐伦成矿带羊场石英脉型钼矿床成矿流体地球化学特征研究

    Institute of Scientific and Technical Information of China (English)

    张作伦; 刘建明; 褚少雄

    2012-01-01

    The Yangchang Mo deposit is located in the Xilamulun molybdenum metallogenic belt on northern margin of North China Craton, Inner Mongolia. The mineralization is occurred within the NW- to NNW- trending faults and fractures hosted by the Yanshanian biotite monzogranite. The ore-forming hydrothermal process can be subdivided into four stages: quartz vein stage ( Ⅰ ) , quartz-pyrite stage ( Ⅱ -1) , quartz-pyrite-molybdenite-chalcopyrite-galena-sphalerite stage ( Ⅱ -2) and carbonate stage ( Ⅲ ). Three types of fluid inclusions are observed in quartz crystals, I. E. Liquid-rich ( VH2O 94. 39mol% ) , with minor CO2, N2, CH4 , C2H6, Ar, H2S, and Na+ , HS , Cl ions. These suggest the Yangchang Mo deposit was formed in reduction condition and the ore-forming fluids were of the NaCl-H2 O ± CO2 system. Hydrogen and oxygen isotopes of fluid inclusions in various mineralization stages are - 119. 66‰ ~ - 98. 79‰ and - 0. 08‰ ~ 1. 90‰ respectively, indicating that the ore-forming fluids were the mixture of magmatic water and meteoric water. It is suggested that the mixing of different fluids with distinct natures might be responsible for the precipitation of molybdenite.%内蒙古羊场钼矿床产于华北克拉通北缘西拉沐伦钼多金属成矿带内,矿体主要以石英脉形式产于燕山期黑云母二长花岗岩内,受NW、NNW向断裂构造控制.成矿过程包括石英大脉阶段(Ⅰ)、石英-黄铁矿亚阶段(Ⅱ-1)、石英-黄铁矿-辉钼矿-黄铜矿-方铅矿-闪锌矿亚阶段(Ⅱ-2)、碳酸岩化阶段(Ⅲ).流体包裹体研究发现,按照气相比不同可将包裹体分为WL型(<50%)、WV型(50% ~ 90%)、G型(100%).Ⅰ、Ⅱ-1、Ⅱ-2阶段包裹体均一温度分别为173~ 280℃、180 ~467℃、151 ~366℃,不具有继承演化关系,可能是成矿作用过程中加入有岩浆热液的结果;盐度分别为4.03% ~ 10.61% NaCleqv、2.07%~ 10.36% NaCleqv和2.41% ~9.98% NaCleqv.

  20. Field and Microstructure Study of Transpressive Jogdadi shear zone near Ambaji, Aravalli- Delhi Mobile Belt, NW India and its tectonic implication on the exhumation of granulites.

    Science.gov (United States)

    Tiwari, Sudheer Kumar; Biswal, Tapas Kumar

    2016-04-01

    Aravalli- Delhi mobile belt is situated in the northwestern part of Indian shield. It comprises tectono- magmatic histories from Archean to Neoproterozoic age. It possesses three tectono- magmatic metamorphic belts namely Bhilwara Supergroup (3000 Ma), Aravalli Supergorup (1800 Ma) and Delhi Supergroup (1100 -750Ma). The Delhi Supergroup is divided in two parts North Delhi and South Delhi; North Delhi (1100 Ma to 850 Ma) is older than South Delhi (850 Ma to 750 Ma). The study area falls in the South Delhi terrane; BKSK granulites are the major unit in this terrane. BKSK granulites comprise gabbro- norite-basic granulite, pelitic granulite, calcareous granulite and occur within the surrounding of low grade rocks as meta- rhyolite, quartzite, mica schist and amphibolites. The high grade and low grade terranes share a sheared margin. Granulites have undergone three phases of folding, intruded by three phases of granites and traversed by many shear zones. One of the shear zones is Jogdadi shear zone which consists of granitic mylonites and other sheared rocks. Jogdadi shear zone carries the evidence of both ductile as well as brittle shearing. It strikes NW- SE; the mylonitic foliation dip moderately to SW or NE and stretching lineations are oblique towards SE. The shear zone is folded and gabbro- norite - basic granulite occurs at the core. One limb of fold passes over coarse grained granite while other limb occurs over gabbro- norite- basic granulite. Presence of mylonitic foliation, asymmetric folding, S-C fabrics, porphyroclasts, mica fishes and book shelf- gliding are indicative of ductile deformation. Most of the porphyroclasts are sigmoidal and delta types but there are also some theta and phi type porphyroclasts. Book shelf-gliding structures are at low angle to the C plane. The shear zone successively shows protomylonite, mylonite and ultramylonites from margin to the centre. As the mylonitization increases recrystallized quartz grains appear. Porphyroclasts

  1. The role of magma mixing in the evolution of the Early Paleozoic calc-alkaline granitoid suites. Eastern magmatic belt, Puna, NW Argentina

    Science.gov (United States)

    Suzaño, Néstor; Becchio, Raúl; Sola, Alfonso; Ortiz, Agustín; Nieves, Alexis; Quiroga, Mirta; Fuentes, Gabriela

    2017-07-01

    The outcrops of the Eastern magmatic belt in Puna, NW Argentina, offer an excellent field laboratory to study the interaction processes between magmas of contrasting composition in a plutonic environment. We evaluate the genesis of Cambrian-Ordovician intermediate to acid rocks from the Diablillos Intrusive Complex and the Cerro Bayo area, through detailed geological, petrographic, mineralogical, geochemical, and Nd isotopic analyses in combination with published data. These localities display a great variety of magmatic rocks from diorite/Qz-diorite to two-mica syenogranites with tonalite, granodiorite, monzogranite and Bt-Ttn-leucogranites as mixed products. Major, trace element and whole-rock Nd isotope modeling and petrological data, suggests that magma mixing between hydrous juvenile mantle- and crustal-derived magmas contributed significantly to the geochemical variation of these granites. The estimated proportion of mafic component 0.40-0.67 and 0.14-0.35 in the mixtures may produce the tonalite-granodiorites and monzogranites magmas. The mixing model excludes the predominant influence of fractional crystallization from a mafic magma and local assimilation-fractional-crystallization processes. Isotopic and geochemical comparison between the studied rocks and the magmatic belts in Puna and Tastil batholith suites reveals a marked resemblance. The data suggests that those rocks were probably generated by magma mixing and denotes a regionally and continuous process in a long-lasting (∼540-440 Ma) active continental margin. We propose that partial melting of the crust and magma mixing occurred in the lower crust and was possibly triggered by underplated and intraplated hydrous (4.37-5.91 wt% H2O) mafic magmas. The hybrid magmas were emplaced at shallow depth (∼8-9 km, 684-727 °C) and occasionally injected either by synplutonic-to late successive pulses of mafic magmas.

  2. Post-collisional magmatism: Consequences of UHPM terrane exhumation and orogen collapse, N. Qaidam UHPM belt, NW China

    Science.gov (United States)

    Wang, Mengjue; Song, Shuguang; Niu, Yaoling; Su, Li

    2014-12-01

    Exhumation of subducted slabs and extensional collapse of orogens are the main tectonic processes in ancient and modern continental collisional zones. Magmatism during these two processes may play important roles in understanding reworking and growth of the continental crust. We report here that a series of plutonic magmas, including intrusions of two-mica granite, tonalite, granodiorite, biotite monzogranite, porphyritic biotite granite and diorite, as well as contemporaneous mafic dykes, have been recognized in Dulan eclogite-bearing terrane, the North Qaidam ultra-high pressure metamorphic (UHPM) belt. The magmatism represented by these plutons is temporally ~ 20-30 million years (Mys) younger than the UHPM age, lasting for ~ 40 Mys and derived from different sources with different mechanisms. The magmatism was initiated by exhumation of UHPM terranes during which strongly-peraluminous two-mica granite and metaluminous tonalite were produced respectively by decompression melting of the exhumed UHPM upper and lower continental crust, respectively. The genesis of mafic magmatic enclave (MME)-hosting granodiorite with a clear hybrid signature and coeval biotite monzogranite reflected the upwelling of asthenospheric mantle by extension of lithosphere during the orogen collapse. It was induced by detachment of the subducted lithospheric mantle, which then brought heat and mantle material into continental crust and triggered the partial melting of the exhumed UHPM continental crust, and gave rise to mixing of crustal and mantle melts. Porphyritic biotite granite reflects a late melting event of continental crust. Diorite marked by high magnesium content represents mantle melts with slight crustal contamination, which implies that the orogen has been unrooted and collapsed completely. The post-collisional magmatism of the North Qaidam belt provides an improved understanding for the late thermal and tectonic evolution of a UHPM continental collision zone.

  3. Holocene hydrological changes in the Rhône River (NW Mediterranean) as recorded in the marine mud belt

    Science.gov (United States)

    Bassetti, Maria-Angela; Berné, Serge; Sicre, Marie-Alexandrine; Dennielou, Bernard; Alonso, Yoann; Buscail, Roselyne; Jalali, Bassem; Hebert, Bertil; Menniti, Christophe

    2016-07-01

    Expanded marine Holocene archives are relatively scarce in the Mediterranean Sea because most of the sediments were trapped in catchment areas during this period. Mud belts are the most suitable targets to access expanded Holocene records. These sedimentary bodies represent excellent archives for the study of sea-land interactions and notably the impact of the hydrological activity on sediment accumulation. We retrieved a 7.2 m long sediment core from the Rhône mud belt in the Gulf of Lions in an area where the average accumulation rate is ca. 0.70 m 1000 yr-1. This core thus provides a continuous and high-resolution record of the last 10 ka cal BP. A multiproxy dataset (XRF core scan, 14C dates, grain size and organic-matter analysis) combined with seismic stratigraphic analysis was used to document decadal to centennial changes in the Rhône hydrological activity. Our results show that (1) the early Holocene was characterized by high sediment delivery likely indicative of local intense (but short-duration) rainfall events, (2) important sediment delivery around 7 ka cal BP presumably related to increased river flux, (3) a progressive increase in continental/marine input during the mid-Holocene despite increased distance from river outlets due to sea-level rise possibly related to higher atmospheric humidity caused by the southward migration of the storm tracks in the North Atlantic, (4) multidecadal to centennial humid events took place in the late Holocene. Some of these events correspond to the cold periods identified in the North Atlantic (Little Ice Age, LIA; Dark Ages Cold Period) and also coincide with time intervals of major floods in the northern Alps. Other humid events are also observed during relatively warm periods (Roman Humid Period and Medieval Climate Anomaly).

  4. 基于多元信息的证据权法在南岭钨锡多金属成矿预测中的应用%Application of weights of evidence method for prediction of W-Sn polymetallic deposits based on multi-source information in Nanling metallogenic belt

    Institute of Scientific and Technical Information of China (English)

    雷天赐; 罗士新; 王磊

    2016-01-01

    以南岭成矿带1∶50万地质数据库、物化探数据为信息源,通过数据处理、分析与推断,编制相关成果图件。以GIS为平台、地质异常理论为指导,基于多元信息成矿耦合分析与异常提取,优选找矿要素有利区间并构建了13个有效证据层,基于Morpas、Arc-wofe证据权模型开展了成矿定量预测与评价。以0.024、0.078和0.098为后验概率临界值划分了三级成矿远景区,共圈定一级远景区41个、二级远景区70个和三级远景区85个,为该区找矿工作部署及资源规划提供了参考。%According to1:500000 geological database, geophysical and geochemical exploration data in Nanling metallogenic belt, all kinds of related maps were compiled by data-processing, analyzing and interpreting. On ba-sis of the GIS platform, guided by the geological anomaly theory, all favorable ranges of prospecting factors were selected through multi-information metallogenic coupling analysis and anomalous information extraction. Finally, 13 effective evidence layers were built. Ore-forming quantitative prediction and assessment was done based on weights of evidence of Morpas and Arc-wofe model. According to the critical value of 0.024、0.078 and 0.098, 41 for prospecting,70 secondary prospect areas and 85 triple prospect areas were submited, it was significanct to plan work and plan mineral resources in the region.

  5. 西藏冈底斯多金属成矿带铅锌矿定位预测与资源潜力评价%Regional metallogenic predication and mineral reserves evaluation of lead and zinc deposits in the Gangdise polymetallic ore-forming belt,Tibet

    Institute of Scientific and Technical Information of China (English)

    谭钢; 佘宏全; 常帼雄; 李光明; 董英君; 潘桂棠; 李进文; 张德全; 丰成友

    2011-01-01

    矽卡岩型和热液脉型铅锌多金属矿是冈底斯地区铅锌资源量的主要来源.本文在全面收集冈底斯成矿带及其周边(主要包括冈底斯及其以南的喜马拉雅带)地质、矿产、物探、化探、遥感等基础地质资料的基础上,建立了GIS 平台基础上的资源预测评价系统.运用特征分析模型和数理统计方法,分别确定了预测区内矽卡岩型和热液脉型铅锌多金属矿定位预测的找矿模型和定量化标志,其中对铅锌矿预测比较重要的地质变量(变量权重>0.2)有中酸性花岗质侵入岩体,其他类型矿床(点),Cu、Pb、Zn、Ag、Cd、Au、Bi 单元素化探异常,Cu-Pb-Zn-Ag、Pb-Zn、Pb-Zn-Ag-Cd 组合化探异常,磁异常正负场变化,中低负重力异常场等.在此基础上,利用 MRAS 资源评价系统,圈定了铅锌矿成矿远景区共 57 处,总体上预测成果与实际地质情况及已知矿床(点)分布吻合较好.采用面金属量法估算了各远景区的铅锌矿资源量.统计结果表明,预测区内 1000 m 以浅潜在铅锌资源总量可达 2.9 亿吨,指示了冈底斯成矿带及其周边仍具有良好的铅锌矿找矿远景和资源潜力.%Skarn and hydrothermal vein deposits constitute the main resources of lead and zinc in the Gangdise metallogenic belt.In recent years, especially since the beginning of the Geological Survey Project in 1999, great progress in geological survey and resource exploration has been made, several large-size lead and zinc ore deposits have been discovered, and many important regional geological data have been accumulated in Gangdise region.Based on detailed collection of geological, ore deposits, minerals, geophysical and geochemical data and remotesensing information in this region, the authors established a mineral resources evaluation system based on GIS technology.The basic data of the mineral resources evaluation system cover a wide range of information, which includes geology (stratigraphy

  6. How many sutures in the southern Central Asian Orogenic Belt: Insights from East Xinjiang–West Gansu (NW China?

    Directory of Open Access Journals (Sweden)

    Wenjiao Xiao

    2014-07-01

    Full Text Available How ophiolitic mélanges can be defined as sutures is controversial with regard to accretionary orogenesis and continental growth. The Chinese Altay, East Junggar, Tianshan, and Beishan belts of the southern Central Asian Orogenic Belt (CAOB in Northwest China, offer a special natural laboratory to resolve this puzzle. In the Chinese Altay, the Erqis unit consists of ophiolitic mélanges and coherent assemblages, forming a Paleozoic accretionary complex. At least two ophiolitic mélanges (Armantai, and Kelameili in East Junggar, characterized by imbricated ophiolitic mélanges, Nb-enriched basalts, adakitic rocks and volcanic rocks, belong to a Devonian–Carboniferous intra-oceanic island arc with some Paleozoic ophiolites, superimposed by Permian arc volcanism. In the Tianshan, ophiolitic mélanges like Kanggurtag, North Tianshan, and South Tianshan occur as part of some Paleozoic accretionary complexes related to amalgamation of arc terranes. In the Beishan there are also several ophiolitic mélanges, including the Hongshishan, Xingxingxia–Shibangjing, Hongliuhe–Xichangjing, and Liuyuan ophiolitic units. Most ophiolitic mélanges in the study area are characterized by ultramafic, mafic and other components, which are juxtaposed, or even emplaced as lenses and knockers in a matrix of some coherent units. The tectonic settings of various components are different, and some adjacent units in the same mélange show contrasting different tectonic settings. The formation ages of these various components are in a wide spectrum, varying from Neoproterozoic to Permian. Therefore we cannot assume that these ophiolitic mélanges always form in linear sutures as a result of the closure of specific oceans. Often the ophiolitic components formed either as the substrate of intra-oceanic arcs, or were accreted as lenses or knockers in subduction-accretion complexes. Using published age and paleogeographic constraints, we propose the presence of (1 a major

  7. How many sutures in the southern Central Asian Orogenic Belt:Insights from East XinjiangeWest Gansu (NW China)?

    Institute of Scientific and Technical Information of China (English)

    Wenjiao Xiao; Jun Luo; Chunming Han; Wei Liu; Bo Wan; Ji’en Zhang; Songjian Ao; Zhiyong Zhang; Dongfang Song; Zhonghua Tian

    2014-01-01

    How ophiolitic mélanges can be defined as sutures is controversial with regard to accretionary orogenesis and continental growth. The Chinese Altay, East Junggar, Tianshan, and Beishan belts of the southern Central Asian Orogenic Belt (CAOB) in Northwest China, offer a special natural laboratory to resolve this puzzle. In the Chinese Altay, the Erqis unit consists of ophiolitic mélanges and coherent assemblages, forming a Paleozoic accretionary complex. At least two ophiolitic mélanges (Armantai, and Kelameili) in East Junggar, characterized by imbricated ophiolitic mélanges, Nb-enriched basalts, adakitic rocks and volcanic rocks, belong to a DevonianeCarboniferous intra-oceanic island arc with some Paleozoic ophiolites, superimposed by Permian arc volcanism. In the Tianshan, ophiolitic mélanges like Kanggurtag, North Tianshan, and South Tianshan occur as part of some Paleozoic accretionary complexes related to amalgamation of arc terranes. In the Beishan there are also several ophiolitic mélanges, including the Hongshishan, XingxingxiaeShibangjing, HongliuheeXichangjing, and Liuyuan ophiolitic units. Most ophiolitic mélanges in the study area are characterized by ultramafic, mafic and other components, which are juxtaposed, or even emplaced as lenses and knockers in a matrix of some coherent units. The tectonic settings of various components are different, and some adjacent units in the same mélange show contrasting different tectonic settings. The formation ages of these various com-ponents are in a wide spectrum, varying from Neoproterozoic to Permian. Therefore we cannot assume that these ophiolitic mélanges always form in linear sutures as a result of the closure of specific oceans. Often the ophiolitic components formed either as the substrate of intra-oceanic arcs, or were accreted as lenses or knockers in subduction-accretion complexes. Using published age and paleogeographic con-straints, we propose the presence of (1) a major early Paleozoic

  8. Metamorphism of the Basement of the Qilian Fold Belt in the Minhe-Ledu Area, Qinghai Province, NW China

    Institute of Scientific and Technical Information of China (English)

    蔡金郎; 魏光华; 王庆树

    2002-01-01

    The basement of the central Qilian fold belt exposed along the Minhe-Ledu highway consists of psammiticschists, metabasitic rocks, and crystalline limestone. Migmatitic rocks occur sporadically among psammitic schist andmetabasitic rocks. The mineral assemblage of psammitic schist is muscovite + biotite + feldspar + quartz + tourmaline ±titanite ± sillimanite and that of metabasitic rocks is amphibole + plagioclase + biotite ± apatite ± magnetite ± pyroxene ±garnet ± quartz. The migmatitic rock consists of leucosome and restite of various volume proportions; the former consistsof muscovite + alkaline feldspar + quartz ± garnet ± plagioclase while the latter is either fragments of psammitic schist orthose of metabasitic rock. The crystalline limestone consists of calcite that has been partly replaced by olivine. The olivinewas subsequently altered to serpentine. Weak deformations as indicated by cleavages and fractures were imposed promi-nently on the psammitic schists, occasionally on metabasitic rocks, but not on migmatitic rocks. The basement experiencedmetamorphism up to temperature 606-778C and pressure 4.8-6.1 kbar (0.48-0.61 GPa), equivalent to amphibolite-granulite facies. The peak of the metamorphism is marked by a migmatization which occurred at several localities alongthe studied route 587-535 Ma ago. The basement also recorded a retrograde metamorphism of greenschist facies, duringwhich biotite, garnet, amphibole, and pyroxene were partly altered to chlorite.

  9. Historical and geochemical outlines of the oil-gas seepage near Turzovka town; Flysch belt, NW Slovakia

    Directory of Open Access Journals (Sweden)

    Juraj Macek

    2012-06-01

    Full Text Available Small oil deposits located in Korňa near the town of Turzovka in north-western Slovakia and other small deposits located in the Miková region of northern-eastern Slovakia were the first oil deposits discovered and exploited in these parts of the Western Carpathians. Small volumes of oil, natural gas and water rises to the surface on a northern slope in Korňa and several tenths of metres further on these descends into the soil cover and entered the local Kornianka creek. Korňa and its broader surrounds are geologically part of the Magura Nappe of the Carpathian Flysch Belt. The preliminary gas chromatography results indicate weakly biodegraded mature oil with a prevailing aliphatic hydrocarbon fraction. Weak biodegradation and continuous outflow over 100 years following its discovery in 1901 indicate its connection with a deeper oil reservoir. Although methane is the dominant component of this natural gas, the presence of higher gaseous hydrocarbons with the methane carbon isotopic composition indicates a methane gas associated with the main stage of oil generation.

  10. Short episodes of crust generation during protracted accretionary processes: Evidence from Central Asian Orogenic Belt, NW China

    Science.gov (United States)

    Tang, Gong-Jian; Chung, Sun-Lin; Hawkesworth, Chris J.; Cawood, P. A.; Wang, Qiang; Wyman, Derek A.; Xu, Yi-Gang; Zhao, Zhen-Hua

    2017-04-01

    Accretionary orogens are major sites of generation of continental crust but the spatial and temporal distribution of crust generation within individual orogens remains poorly constrained. Paleozoic (∼540-270 Ma) granitic rocks from the Alati, Junggar and Chinese Tianshan segments of the Central Asian Orogenic Belt (CAOB) have markedly bimodal age frequency distributions with peaks of ages at ∼400 Ma and 280 Ma for the Altai segment, and ∼430 Ma and 300 Ma for the Junggar and Chinese Tianshan segments. Most of the magma was generated in short time intervals (∼20-40 Ma), and variations in magma volumes and in Nd-Hf isotope ratios are taken to reflect variable rates of new crust generation within a long-lived convergent plate setting. The Junggar segment is characterized by high and uniform Nd-Hf isotope ratios (εNd (t) = + 5 to + 8; zircon εHf (t) = + 10 to + 16) and it appears to have formed in an intra-oceanic arc system. In the Altai and Chinese Tianshan segments, the Nd-Hf isotope ratios (εNd (t) = - 7 to + 8; zircon εHf (t) = - 16 to + 16) are lower, although they increase with decreasing age of the rock units. The introduction of a juvenile component into the Chinese Tianshan and Altai granitic rocks appears to have occurred in continental arc settings and it reflects a progressive reduction in the contributions from old continental lower crust and lithospheric mantle. Within the long-lived convergent margin setting (over ∼200 Ma), higher volumes of magma, and greater contributions of juvenile material, were typically emplaced over short time intervals of ∼20-40 Ma. These intervals were associated with higher Nb/La ratios, coupled with lower La/Yb ratios, in both the mafic and granitic rocks, and these episodes of increased magmatism from intraplate-like sources are therefore thought to have been in response to lithospheric extension. The trace element and Nd-Hf isotope data, in combination with estimates of granitic magma volumes, highlight

  11. Mafic rocks from Erinpura gneiss terrane in the Sirohi region: Possible ocean-floor remnants in the foreland of the Delhi Fold Belt, NW India

    Indian Academy of Sciences (India)

    M K Pandit; H De Wall; H Daxberger; J Just; M Bestmann; K K Sharma

    2011-08-01

    A small isolated mafic body occurs to the south of Sirohi near village Daba within the Neoproterozoic Erinpura Granite in the southern sector of the Proterozoic Delhi Fold Belt in NW India. This mafic body occurs close to a 100 m wide NE–SW trending shear zone (Daba Shear Zone) which overprints the felsic rock fabrics. Further south, a small mafic body near village Kui was also sampled which forms the southern limit of the Phulad Ophiolite Suite which is a 300 km long major NE–SW trending lineament, described as Western Margin Fault. Some of the lithological components of the Daba mafic body show locally preserved magmatic fabric but completely transformed mineralogies under lower amphibolites facies metamorphic conditions where two-stage deformation has been inferred. Magnetic fabric analysis underlines a general correspondence of structural elements in both felsic and mafic lithologies. Binary correlations of Zr with other high field strength elements underline fractionation as the main process in the evolution of Daba and Kui rocks. Geochemical characteristics indicate subalkaline tholeiitic basalt affinity for these mafic rocks. The trace element characteristics, such as enriched LIL elements, high Th, absence of negative Nb anomalies and depletion in compatible elements in Daba samples suggest an enriched mantle source and lower degree of melting. The trace and rare earth element characteristics for Kui (Th anomaly, Nb–Ta trough and less spiked patterns, flat REE trends) indicate derivation from a refractory mantle source affected by fluids derived from subduction. Distinct differences in trace and REE characteristics between Daba and Kui can be interpreted in terms of different stages of ophiolite development.

  12. A synthesis of mineralization styles with an integrated genetic model of carbonatite-syenite-hosted REE deposits in the Cenozoic Mianning-Dechang REE metallogenic belt, the eastern Tibetan Plateau, southwestern China

    Science.gov (United States)

    Liu, Yan; Hou, Zengqian

    2017-04-01

    The Cenozoic Mianning-Dechang (MD) rare earth element (REE) belt in eastern Tibet is an important source of light REE in southwest China. The belt is 270 km long and 15 km wide. The total REE resources are >3 Mt of light rare earth oxides (REO), including 3.17 Mt of REO at Maoniuping (average grade = 2.95 wt.%), 81,556 t at Dalucao (average grade = 5.21 wt.%), 0.1 Mt at Muluozhai (average grade = 3.97 wt.%), and 5764 t of REO at Lizhuang (average grade = 2.38 wt.%). Recent results from detailed geological surveys, and studies of petrographic features, ore-forming ages, ore forming conditions, and wallrock alteration are synthesized in this paper. REE mineralization within this belt is associated with carbonatite-syenite complexes, with syenites occurring as stocks intruded by carbonatitic sills or dikes. The mineralization is present as complex vein systems that contain veinlet, stringer, stockwork, and brecciated pipe type mineralization. Carbonatites in these carbonatite-related REE deposits (CARDs) are extremely rich in light REEs, Sr (>5000 ppm), and Ba (>1000 ppm), and have low Sr/Ba and high Ba/Th ratios, and radiogenic Sr-Nd isotopic compositions. These fertile magmas, which may lead to the formation of REE deposits, were generated by the partial melting of sub-continental lithospheric mantle (SCLM) that was metasomatized by REE- and CO2-rich fluids derived from subducted marine sediments. We suggest that this refertilization occurred along cratonic margins and, in particular, at a convergent margin where small-volume carbonatitic melts ascended along trans-lithospheric faults and transported REEs into the overlying crust, leading to the formation of the CARDs. The formation of fertile carbonatites requires a thick lithosphere and/or high pressures (>25 kbar), a metasomatized and enriched mantle source, and favorable pathways for magma to ascend into the overlying crust where REE-rich fluids exsolve from cooling magma. The optimal combination of these three

  13. Provenance and tectonic setting of siliciclastic rocks associated with the Neoproterozoic Dahongliutan BIF: Implications for the Precambrian crustal evolution of the Western Kunlun orogenic belt, NW China

    Science.gov (United States)

    Hu, Jun; Wang, He; Wang, Min

    2017-10-01

    The Late Neoproterozoic Dahongliutan BIF is associated with siliciclastic rocks in the Tianshuihai terrane of the Western Kunlun orogenic belt (WKO), NW China. The sedimentary rocks have various weathering indices (e.g., CIA = 57-87, PIA = 61-96 and Th/U = 4.85-12.45), indicative of varying degrees of weathering in the source area. The rocks have trace element ratios, such as Th/Sc = 0.60-1.21 and Co/Th = 0.29-1.67, and light rare earth element (LREE) enriched chondrite-normalized REE patterns, suggesting that they were mainly sourced from intermediate and felsic rocks. Available U-Pb ages of detrital zircon from these rocks reveal that the detrital sources may have been igneous and metamorphic rocks from the WKO and the Tarim Block. Our study suggests that the Dahongliutan BIF and hosting siliciclastic rocks may have deposited in a setting transitional from a passive to active continental margin, probably related to the Late Neoproterozoic-Early Cambrian seafloor spreading and subduction of the Proto-Tethys Ocean. U-Pb dating of 163 detrital zircons defines five major age populations at 2561-2329 Ma, 2076-1644 Ma, 1164-899 Ma, 869-722 Ma and 696-593 Ma. These age groups broadly correspond to the major stages of supercontinent assembly and breakup events widely accepted for Columbia, Rodinia and Gondwana. Some zircons have TDM2 model ages of 3.9-1.8 Ga and negative εHf(t) values, suggesting that the Archean to Paleoproterozoic (as old as Eoarchean) crustal materials were episodically reworked and incorporated into the late magmatic process in the WKO. Some Neoproterozoic zircons have TDM2 model ages of 1.47-1.07 Ga and 1.81-1.53 Ga and positive εHf(t) values, indicating juvenile crustal growth during the Mesoproterozoic. Our new results, combined with published data, imply that both the Tianshuihai terrane in the WKO and the Tarim Block share the same Precambrian tectonic evolution history.

  14. Oceanic plateau model for continental crustal growth in the Archaean: A case study from the Kostomuksha greenstone belt, NW Baltic Shield

    Science.gov (United States)

    Samsonov, A. V.; Shchipansky, A. A.; Jochum, K. P.; Mezger, K.; Hofmann, A. W.; Puchtel, I. S.

    1998-02-01

    Field studies combined with chemical and isotope data indicate that the Kostomuksha greenstone belt in the NW Baltic Shield consists of two lithotectonic terranes, one mafic igneous and the other sedimentary, separated by a major shear zone. The former contains submarine komatiite-basalt lavas and volcaniclastic lithologies, and the latter is composed of shelf-type rocks and BIF. Komatiitic and basaltic samples yield Sm-Nd and Pb-Pb isochron ages of 2843+/-39 and 2813+/-78 Ma, respectively. Their trace-element compositions resemble those of recent Pacific oceanic flood basalts with primitive-mantle normalized Nb/Th of 1.5-2.1 and Nb/La of 1.0-1.5. This is in sharp contrast with island arc and most continental magmas, which are characterized by Nb/(Th,La)N≪1. Calculated initial Nd-isotope compositions (ɛNd(T)=+2.8 to +3.4) plot close to an evolution line previously inferred for major orogens (``MOMO''), which is also consistent with the compositions of recent oceanic plateaux. The high liquidus temperatures of the komatiite magmas (1550°C) and their Al-depleted nature require an unusually hot (1770°C) mantle source for the lavas (>200°C hotter than the ambient mantle at 2.8 Ga), and are consistent with their formation in a deep mantle plume in equilibrium with residual garnet. This plume had the thermal potential to produce oceanic crust with an average thickness of ~30 km underlain by a permanently buoyant refractory lithospheric mantle keel. Nb/U ratios in the komatiites and basalts calculated on the basis of Th-U-Pb relationships range from 35 to 47 and are thus similar to those observed in modern MORB and OIB. This implies that some magma source regions of the Kostomuksha lavas have undergone a degree of continental material extraction comparable with those found in the modern mantle. The mafic terrane is interpreted as a remnant of the upper crustal part of an Archaean oceanic plateau. When the newly formed plateau reached the active continental margin

  15. Reconstructing multiple arc-basin systems in the Altai-Junggar area (NW China): Implications for the architecture and evolution of the western Central Asian Orogenic Belt

    Science.gov (United States)

    Li, Di; He, Dengfa; Tang, Yong

    2016-05-01

    The Altai-Junggar area in northwestern China is a critical region to gain insights on the tectonic framework and geological evolution of the western Central Asian Orogenic Belt (CAOB). In this study, we report results from integrated geological, geochemical and geophysical investigations on the Wulungu Depression of the Junggar Basin to determine the basement nature of the basin and understand its amalgamation history with the Chinese Altai, within the broad tectonic evolution of the Altai-Junggar area. Based on borehole and seismic data, the Wulungu Depression is subdivided into two NW-trending tectonic units (Suosuoquan Sag and Hongyan High) by southward-vergent thrust faults. The Suosuoquan Sag consists of the Middle-Late Devonian basaltic andesite, andesite, dacite, tuff, tuffaceous sandstone and tuffite, and the overlying Early Carboniferous volcano-sedimentary sequence with lava flows and shallow marine sediments from a proximal juvenile provenance (zircon εHf(t) = 6.0-14.9), compared to the Late Carboniferous andesite and rhyolite in the Hongyan High. Zircon SIMS U-Pb ages for dacites and andesites indicate that these volcanics in the Suosuoquan Sag and Hongyan High erupted at 376.3 Ma and 313.4 Ma, respectively. The Middle-Late Devonian basaltic andesites from well LC1 are calc-alkaline and exhibit primitive magma-like MgO contents (7.9-8.6%) and Mg# values (66-68), with low initial 87Sr/86Sr (0.703269-0.704808) and positive εNd(t) values (6.6-7.6), and relatively high Zr abundance (98.2-116.0 ppm) and Zr/Y ratios (5.1-5.4), enrichment in LREEs and LILEs (e.g., Th and U) and depletion in Nb, Ta and Ti, suggesting that they were probably derived from a metasomatized depleted mantle in a retro-arc extensional setting. The well LC1 andesitic tuffs, well L8 dacites, well WL1 dacitic tuffs and well L5 andesites belong to calc-alkaline and metaluminous to peraluminous (A/CNK = 0.8-1.7) series, and display low Mg# values (35-46) and variably positive εNd(t) (4

  16. Metallogenic Perspect Prognostication of Carbonaceous siliceous argillaceous Type Uranium Deposit in the Northwestern Margin of Xuefengshan Uplift Belt%雪峰山隆起带西北缘碳硅泥岩型铀矿远景预测

    Institute of Scientific and Technical Information of China (English)

    张字龙; 漆富成; 付锦; 李治兴

    2015-01-01

    Based on the characteristics and ore forming conditions in Pan'gongtan deposit , the ore hos‐ting bed (Niutitang formation of Lower Cambrian) , NE striking faults ,downfaulted red basin and Cam‐biran lithofacies paleogeography are regarded as the primary ore controlling factors in the region .Ac‐cording to regional geochemical exploration , Mo , V and Ag are closely related to uranium metallogenssis. According to the technical request in National Potential Evaluation of Uranium Re‐sources ,geological conditions and prognosis factors for the evaluation carbonaceous siliceous argilla‐ceous rock type uranium deposit was summarized in the northwestern margin of Xuefengshan uplift belt . The uranium potential of carbonaceous siliceous argillaceous rock type has been estimated in the area , which can provide scientific basis to uranium exploration and strategic target selection .%文章通过分析潘公潭铀矿床的成矿特征和成矿条件,认为雪峰山隆起带西北缘地区的铀成矿作用主要受赋矿地层(下寒武统牛蹄塘组)、 NE 向断裂、断陷红盆和寒武纪岩相古地理等因素控制。区域化探表明, Mo 、 V 和 Ag 等元素与铀成矿关系密切,对指导找矿有重要作用。根据全国铀矿资源潜力评价技术要求,通过总结、归纳区内碳硅泥岩型铀矿成矿地质要素和预测要素,采用固体矿产矿床模型综合地质信息预测技术,预测了有利成矿远景区,为该区铀矿地质勘查提供依据。

  17. Study of tectonic layering motion and layering mineralization in the Tongling metallogenic cluster

    Institute of Scientific and Technical Information of China (English)

    吴淦国; 张达; 臧文拴

    2003-01-01

    Analysis of the deep tectonics and cover tectonic deformations shows that tectonic layering motion is a typical lithospheric characteristic in the Tongling area and the metallogenic belt of the middle-lower Yangtze. Controlling of the deep tectonosphere over the shallow-seated tectonosphere involves various grades of tectonic layering motions. Multi-layer, multi-grade, and multi-directional gliding tectonics are the specific modes of tectonic layering motions in the cover of the Tongling metallogenic cluster. The gliding tectonics developed based on S-shaped folds of the Indosinian, and was continuously active in the Yanshanian. They correspond to the deformation systems of the EW and NNE extensions. The control of tectonic layering motion acts against ore-forming processes, the different interlayer gliding belts can easily form different genetic-type deposits, and the ore-forming features of different parts of the same gliding layer are different. All of these characters are closely related to tectonic gliding mechanisms, tectonic compounding characteristics, features of metallogenic wall rocks, and types of ore-forming hydrothermal solutions.

  18. 高分遥感卫星数据在东昆仑成矿带找矿预测中的应用%Application of high resolution remote sensing data to ore-prospecting prediction in East Kunlun metallogenic belt

    Institute of Scientific and Technical Information of China (English)

    张微; 金谋顺; 张少鹏; 陈玲; 钟昶; 董丽娜

    2016-01-01

    Through geological interpretation and alteration anomaly information extraction with remote sensing, rapid pre-selection of large ore concentration areas and delineation of potential mineralization areas can be carried out. In this paper, with the Hongshui River region of the East Kunlun metallogenic belt as a case study, by using WorldView-2 remote sensing images as major data source and adopting methods of image rectification, false color composition, image enhancement, data fusion, alteration anomaly information extraction, field validation, chemical analysis and geological integrated analysis, the authors predicted the potential regions of mineral resources. The results show that the remote sensing technology using high resolution satellite images can be used as an effective method for detection of potential mineral resources enrichment region, which can meet the requirements of mineral resources exploration and assessment in the arid and semi-arid regions in West China and provide the basic data and reference for the deployment of mineral resources exploration.%为研究高分辨率(简称“高分”)遥感卫星数据在东昆仑成矿带找矿预测中的应用,通过遥感地质解译与蚀变异常信息提取,从宏观和多角度开展大型矿集区快速预选和找矿有利地段圈定。以东昆仑成矿带红水河地区为研究区,以WorldView-2卫星图像为主要数据源,通过运用图像纠正、假彩色合成、图像增强、数据融合、遥感蚀变异常信息提取、野外验证、化学分析和地质信息综合研究等方法,对研究区进行了遥感地质解译和找矿预测。结果表明,以高分遥感卫星数据为主的数据源,能够快速圈定找矿有利地段,满足我国西部干旱—半干旱地区的矿产资源勘查和资源评价需求,并为当地矿产勘查工作部署提供基础资料和参考依据。

  19. Long-term landscape evolution of the South Atlantic passive continental margin along the Kaoko- and Damara Belts, NW-Namibia

    Science.gov (United States)

    Menges, Daniel; Glasmacher, Ulrich Anton; Hackspacher, Peter; Schneider, Gabriele; Salomon, Eric

    2015-04-01

    The Kaoko Belt in northwestern Namibia originates in the collision of the Rio de la Plata and Kongo Craton during the Pan-African Orogeny in the Neoproterozoic (1) and represents the northern arm of the Damara Orogen. NW-Namibias continental crust mainly consists of the NE-SW striking intracontinental branch of the Pan-African Damara mobile belt, which separates the Congo from the Kalahari craton. The Damara Orogen is divided into several tectonostratigraphic zones that are bounded by steeply dipping, ductile shear zones. These regional lineaments can be traced at least 150 km offshore (2). The lithostratigraphic units consist of Proterozoic and Cambrian metamorphosed rocks (534 (7) Ma - 481 (25) Ma (3) as well as Mesozoic sedimentary and igneous rocks. From Permo-Carboniferous to Mid Jurassic northern Namibia was affected by deep erosion of the Damara Orogen, Permo-Triassic collisional processes along the southern margin of Gondwana and eastern margin of Africa (4), and the deposition of the Nama Group sediments and the Karoo megasequence (5). Between the Otjihorongo and the Omaruru Lineament-Waterberg Thrust early Mesozoic tectonic activity is recorded by coarse clastic sediments deposited within NE trending half-graben structures. The Early Jurassic Karoo flood basalt lavas erupted rapidly at 183±1 Ma (6). The Early Cretaceous Paraná-Etendeka flood basalts (132±1 Ma) and mafic dike swarms mark the rift stage of the opening of the South Atlantic (7). Early Cretaceous alkaline intrusions (137-124 Ma) occur preferentially along Mesozoic half-graben structures and are called the Damaraland Igneous Province (8). Late Cretaceous alkaline intrusions and kimberlite pipes occur in northern Namibia. Post Early Paleocene siliciclastic sedimentation in Namibia was largely restricted to a 150 km wide zone (9) and is represented by the Tsondab Sandstone Formation (~ 300 m thickness). The oldest part has an age of early Paleocene and the upper part span from middle Miocene

  20. From oceanic subduction to continental collision: An overview of HP-UHP metamorphic rocks in the North Qaidam UHP belt, NW China

    Science.gov (United States)

    Zhang, Guibin; Zhang, Lifei; Christy, Andrew G.

    2013-02-01

    The North Qaidam UHPM belt is unique among "continental type" subduction zones in showing well-preserved subducted oceanic relics that predate continental subduction and collision. We review petrologic, thermobarometric, geochemical and geochronological studies for the Yuka, Luliang Shan, Xitieshan and Dulan terranes in this belt. UHP conditions are demonstrated by coesite inclusions in eclogite and country gneiss, and diamond inclusions from garnet peridotite. The relict subducted oceanic lithology crops out in the Shaliuhe cross-section in Dulan terrane; it originated as the floor of a Paleo-Qilian Ocean that existed between Qaidam and Qilian blocks before the early Ordovician. Whereas most eclogites of this belt are derived from mafic rocks of either a Neoproterozoic continental rift or incipient oceanic basin setting, which were subducted along with continental rocks in the early Paleozoic. The data, especially the two protolith sources for eclogites, demonstrate tectonic evolution of the North Qaidam UHPM belt from oceanic subduction to continental collision.

  1. Regional metallogenic structure based on aeromagnetic data in northern Chile

    Science.gov (United States)

    Zhu, Xiao-San; Lu, Min-Jie

    2016-12-01

    Chile is a very important country that forms part of the Andean metallogenic belts. The Atacama and Domeyko fault systems in northern Chile control the tectonic-magmatic activities that migrate eastward and the types of mineral resources. In this paper, we processed and interpreted aeromagnetic data from northern Chile using reduction to pole, upward field continuation, the second derivative calculation in the vertical direction, inclination angle calculation, and analytical signal amplitude analysis. We revealed the locations and planar distribution characteristics of the regional deep faults along the NNE and NS directions. Furthermore, we observed that the major reasons for the formation of the tectonic-magmatic rocks belts were the nearly parallel deep faults distributed from west to east and multiple magmatic activities along these faults. We ascertained the locations of volcanic mechanisms and the relationships between them using these regional deep faults. We deduced the spatial distributions of the basic-intermediate, basic, and acidic igneous rocks, intrusive rocks, and sedimentary sequences. We showed the linear positive magnetic anomalies and magnetic anomaly gradient zones by slowly varying the background, negative magnetic anomaly field, which indicated the presence of strong magmatic activities in these regional deep faults; it also revealed the favorable areas of copper and polymetallic mineralization. This study provides some basic information for further research on the geology, structural characteristics, and mineral resource prospecting in northern Chile.

  2. Fission Track Dating on the Paodaoling Gold Deposit in the Middle-Lower Yangtze River Metallogenic Belt: Its significance to Tectonic Setting%长江中下游成矿带抛刀岭金矿裂变径迹研究及大地构造意义

    Institute of Scientific and Technical Information of China (English)

    田朋飞; 杨晓勇; 袁万明; 刘海涛; 薛斌

    2012-01-01

    in late stage and controlled by the temperatures of annealing belts in long time. There are unimodal characterstics in the histogram of track lengths. Analysises of central age (P(x2)xz>5%) and mixed ages(P(x2) x2<5%) reflect that the measured AFT ages lie between 123Ma and 19Ma, which is all significantly younger than those of their host rocks. These ages can be divided into five phases, I. E. , 123. Oma, 107Ma, 86Ma, 52Ma, and 19Ma, respectively. The AFT data modeling identifies a four-stage regional cooling history, I. E. , the first cooling phase of cooling took place from 150Ma to 90Ma with slow cooling rates; the second phase of cooling took place from 90Ma to 65~58Ma with rapid cooling rates; the third phase of cooling took place from 65~58Ma to 18 - 12Ma with slow cooling rates; the fourth phase of cooling took place from 18~12Ma to now with rapid cooling rates. Since Middle Jurassic, Jiangnan uplifted belt is controlled by Pacific Plate tectonics. The movements of Pacific Plate are different in various periods, whose directions and intensities directly control the tectonic evolution of Eastern China. Subdivision of measured fission track ages in this area corresponds with the ages of island chains with different occurrences after the formation of the Pacific Ocean. The results of thermal history modeling are related to movements of the Pacific Plate in different periods. Based on the tectonic-thermal history models and tectonic analysises, we concluded that various stages of thermal history are related to Pacific plate movements in different stages, mixed ages also indicate multiple phases of tectonic activities. Thus we further prove that the stages of tectonic movements in the Guichi area, lower Yangtze metallogenic belt are closely direct response to the Pacific plate activities since Cretaceous.

  3. Confirmation and Significance of Caledonian Metallogenic Epoch for Gold Deposits in South China

    Institute of Scientific and Technical Information of China (English)

    王秀璋; 梁华英; 单强; 程景平; 夏萍

    2001-01-01

    Caledonian gold deposits are widely distributed in South China. They are developed in both South China Caledonian fold belt and adjacent Proterozoic Jiangnan uplift. The host rocks are Proterozoic metamorphosed microclastic rocks in the Jiangnan uplift and Proterozoic and Cambrian strata, as well as Chengjiang and Caledonian igneous bodies in the South China fold belt. The distinct differences between the Caledonian and the most developed Yenshanian gold deposits in South China are reflected in age and host-rock type, relations to Yenshanian magmatic activities, element association, mineral assemblage and gold deposit type. The stud ies have proven that the Caledonian epoch is a principal metallogenic period of gold deposits in South China. This conclusion is of very important enlightening significance in exploration of Caledonian gold deposits in South China as well as in other Caledonian fold belts and adjacent u plifts in China.

  4. Re-Os dating of mineralization in Siah Kamar porphyry Mo deposit (NW Iran) and investigating on its temporal relationship with porphyry Cu-Mo deposits in the southern Lesser Caucasus, NW and central Iran

    Science.gov (United States)

    Simmonds, Vartan; Moazzen, Mohssen; Selby, David

    2017-04-01

    The Neo-Tethyan basin closure in Iran is characterized by the Urumieh-Dokhtar magmatic arc (UDMA), formed by north-eastward subduction of the Neo-Tethyan oceanic crust during the Alpine orogeny. This belt also coincides with the porphyry copper metallogenic belt of Iran, which hosts many porphyry Cu-Mo deposits (PCDs) and prospects, such as Sungun (NW Iran) and Sarcheshmeh (central Iran). The Siah Kamar porphyry Mo deposit (PMD) is the first discovered porphyry molybdenum deposit on this belt, which is located 10 km west of Mianeh (NW Iran), with 39.2 Mt proved reserves @ 539 ppm Mo and 66.4 Mt probable reserves @ 266 ppm Mo. The host porphyry stock has quartz-monzonitic composition, which intruded the volcanic and pyroclastic rocks of Eocene age. Re content of molybdenites is about 10.44-41.05 ppm which, considering the several tens of ppm concentration, is comparable with porphyry Mo deposits (e.g., Climax in USA), being clearly distinguished from porphyry Cu-Mo deposits. Re-Os dating of molybdenites from this PMD has given model ages between 28.1±0.15 to 29.06±0.2 Ma, and isochron age of 28.0±2.1 Ma, corresponding to the middle Oligocene (upper part of Rupelian). Comparing the ages determined for Siah Kamar PMD with porphyry Cu-Mo mineralizations in the Lesser Caucasus indicates that it is younger than most of the dated PCDs and prospects there, especially those of upper Eocene, while it is a little older than Paragachay and first-stage Kadjaran PCDs [1]. In a regional scale of NW Iran, it shows a narrow overlap with vein-type Cu-Mo-Au mineralizations in Qarachilar (Qaradagh batholith) and is nearly coeval with Haftcheshmeh PCD, indicating that mineralization in the Siah Kamar PMD corresponds to the second porphyry mineralization epoch in NW Iran, proposed by [2]. Meanwhile, mineralization in Siah Kamar is older than all the porphyry Cu-Mo mineralizations along the central and SE parts of the UDMA, except the Bondar Hanza PCD in Kerman zone, which nearly

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

    Science.gov (United States)

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

    2017-01-01

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

  6. Tectonic and metallogenic model for northeast Asia

    Science.gov (United States)

    Parfenov, Leonid M.; Nokleberg, Warren J.; Berzin, Nikolai A.; Badarch, Gombosuren; Dril, Sergy I.; Gerel, Ochir; Goryachev, Nikolai A.; Khanchuk, Alexander I.; Kuz'min, Mikhail I.; Prokopiev, Andrei V.; Ratkin, Vladimir V.; Rodionov, Sergey M.; Scotese, Christopher R.; Shpikerman, Vladimir I.; Timofeev, Vladimir F.; Tomurtogoo, Onongin; Yan, Hongquan; Nokleberg, Warren J.

    2011-01-01

    This document describes the digital files in this report that contains a tectonic and metallogenic model for Northeast Asia. The report also contains background materials. This tectonic and metallogenic model and other materials on this report are derived from (1) an extensive USGS Professional Paper, 1765, on the metallogenesis and tectonics of Northeast Asia that is available on the Internet at http://pubs.usgs.gov/pp/1765/; and (2) the Russian Far East parts of an extensive USGS Professional Paper, 1697, on the metallogenesis and tectonics of the Russian Far East, Alaska, and the Canadian Cordillera that is available on the Internet at http://pubs.usgs.gov/pp/pp1697/. The major purpose of the tectonic and metallogenic model is to provide, in movie format, a colorful summary of the complex geology, tectonics, and metallogenesis of the region. To accomplish this goal four steps were taken: (1) 13 time-stage diagrams, from the late Neoproterozoic (850 Ma) through the present (0 Ma), were adapted, generalized, and transformed into color static time-stage diagrams; (2) the 13 time-stage diagrams were placed in a computer morphing program to produce the model; (3) the model was examined and each diagram was successively adapted to preceding and subsequent diagrams to match the size and surface expression of major geologic units; and (4) the final version of the model was produced in successive iterations of steps 2 and 3. The tectonic and metallogenic model and associated materials in this report are derived from a project on the major mineral deposits, metallogenesis, and tectonics of the Northeast Asia and from a preceding project on the metallogenesis and tectonics of the Russian Far East, Alaska, and the Canadian Cordillera. Both projects provide critical information on bedrock geology and geophysics, tectonics, major metalliferous mineral resources, metallogenic patterns, and crustal origin and evolution of mineralizing systems for this region. The major

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

    Indian Academy of Sciences (India)

    T K Biswal; Harish Ahuja; Himansu Sekhar Sahu

    2004-12-01

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

  8. Stages of late Paleozoic to early Mesozoic magmatism in the Song Ma belt, NW Vietnam: evidence from zircon U-Pb geochronology and Hf isotope composition

    Science.gov (United States)

    Hieu, Pham Trung; Li, Shuang-Qing; Yu, Yang; Thanh, Ngo Xuan; Dung, Le Tien; Tu, Vu Le; Siebel, Wolfgang; Chen, Fukun

    2016-05-01

    The Song Ma zone in NW Vietnam bears important tectonic implications as a potential subduction corridor between the Indochina and South China blocks. On the basis of U-Pb ages, the Hf isotopic characteristics of zircons and the geochemical composition of granitoids, a two-stage magmatic evolution process of the Song Ma zone at ~290-260 and ~245-230 Ma can be proposed. Isotopic analyses indicate magmatic contributions from Neoproterozoic oceanic island basalt, Proterozoic continental crust, and depleted mantle or juvenile lithosphere. By combining geochronological and geochemical data from the granitoid rocks, we suggest that the staged magmatic processes of Song Ma zone may be related to a long-lasting period of ocean subduction (ca. 290-260 Ma) and subsequent syn-/post-collisional evolution (ca. 245-230 Ma).

  9. Palaeoproterozoic continental arc magmatism, and Neoproterozoic metamorphism in the Aravalli-Delhi orogenic belt, NW India: New constraints from in situ zircon U-Pb-Hf isotope systematics, monazite dating and whole-rock geochemistry

    Science.gov (United States)

    Kaur, Parampreet; Zeh, Armin; Chaudhri, Naveen

    2017-04-01

    Presently, the extent, origin and petrogenesis of late Palaeoproterozoic (ca. 1.85 Ga) magmatism in the north-central Aravalli-Delhi orogenic belt, NW India and subsequent metamorphic overprints are poorly constrained. Results of new in situ zircon U-Pb-Hf isotope analyses in combination with whole-rock elemental and isotopic data provide the first hard evidence that granitoid magmatism occurred in a continental magmatic arc setting between 1.86 and 1.81 Ga. The Hf-Nd model ages of 3.0-2.6 Ga and inherited zircon grains of 3.3-2.5 Ga indicate abundant reworking of Archaean crust. Flat HREE patterns with negative Eu anomalies furthermore reveal that the granitoids were generated from garnet-free and plagioclase-rich sources at shallow depths. Significant isotope variation among granitoid samples (εHft = -3.7 to -9.0; εNdt = -4.8 to -7.9) indicate that the reworked Archaean crust was not completely homogenised during the Palaeoproterozoic. This is best reflected by zircon Hf-isotope variation of ca. 9.5 epsilon units within the oldest granitoid sample. Zircon grains from this sample define three discrete Hf-isotope groups at εHf1.86Ga = -8.9, -4.8 and -1.6. These are interpreted to result from mixing of zircon-saturated magmas derived from three distinct sources within the crust prior to solidification. A monazite U-Pb isochron age of 868 ± 4 Ma from one of the granitoid samples furthermore indicates that the Aravalli fold belt was affected by an important post-magmatic overprint, perhaps related to the widespread metasomatic, granulite metamorphic and/or magmatic events during the same time span.

  10. METALLOGENIC SYSTEM OF DACHANG TINPOLYMETALLIC ORE FIELD

    Institute of Scientific and Technical Information of China (English)

    WU Xiang-bin; DAI Ta-gen; WANG Zhi-bin; FANG Sheng-kui

    2001-01-01

    The Dachang tin-polymetallic ore field in northern Guangxi,China,lies in a mid-late Paleozoic rift that borders up the southern boundary of the Jiangnan-Xuefeng Massif.As a giant ore deposit,it deposited in middle of the Nandang-Hechi metallogenic zone.The orehosting strata are of the Devonion,which shows the evident characteristics of polymetallic elements,i.e: ,Sn,Zn,Pb,Sb,As,Cu,Ag,In,Ge,Cd,et al.,and over 1 000 000 t tin reserves.

  11. Folding style controlled by intermediate decollement thickness change in the Lurestan region (NW of the Zagros fold-and-thrust belt), using analogue models

    Science.gov (United States)

    Farzipour Saein, Ali

    2017-07-01

    The basal and intermediate decollements play an important role in structural style of fold-and-thrust belts. The decollement units, or different mechanical stratigraphy within the rock units, are not uniform throughout the ZFTB and show a strong spatial variation. The Lurestan region with varied thickness of the intermediate decollement in its northern and southern parts is one of the most important parts of the Zagros fold-and-thrust belt, regarding its hydrocarbon exploration-extraction projects. Thickness variation of the intermediate decollement in different parts of the Lurestan region allows us to address its role on folding style. Based on scaled analogue modeling, this study outlines the impact of thickness and facies variation of sedimentary rocks in the northern and southern parts of this region on folding style. Two models simulated the mechanical stratigraphy and its consequent different folding styles of the northern and southern parts of the region. In the models, only thickness of the intermediate decollement (thick and thin) for the northern and southern parts of the Lurestan region was varied. Detached minor folds above the intermediate decollement were created in response to the presence of the thicker intermediate decollement, northern part of the study area, which consequently deformed complexly and disharmonically folded, in contrast to polyharmonic folding style in the section, compared to polyharmonic folding style in the southern part, where thin intermediate decollement exists. The model results documented that thickness variation of intermediate decollement levels could explain complex and different folding styles in natural examples which must be taken into account for hydrocarbon exploration throughout these areas.

  12. Folding style controlled by intermediate decollement thickness change in the Lurestan region (NW of the Zagros fold-and-thrust belt), using analogue models

    Science.gov (United States)

    Farzipour Saein, Ali

    2016-07-01

    The basal and intermediate decollements play an important role in structural style of fold-and-thrust belts. The decollement units, or different mechanical stratigraphy within the rock units, are not uniform throughout the ZFTB and show a strong spatial variation. The Lurestan region with varied thickness of the intermediate decollement in its northern and southern parts is one of the most important parts of the Zagros fold-and-thrust belt, regarding its hydrocarbon exploration-extraction projects. Thickness variation of the intermediate decollement in different parts of the Lurestan region allows us to address its role on folding style. Based on scaled analogue modeling, this study outlines the impact of thickness and facies variation of sedimentary rocks in the northern and southern parts of this region on folding style. Two models simulated the mechanical stratigraphy and its consequent different folding styles of the northern and southern parts of the region. In the models, only thickness of the intermediate decollement (thick and thin) for the northern and southern parts of the Lurestan region was varied. Detached minor folds above the intermediate decollement were created in response to the presence of the thicker intermediate decollement, northern part of the study area, which consequently deformed complexly and disharmonically folded, in contrast to polyharmonic folding style in the section, compared to polyharmonic folding style in the southern part, where thin intermediate decollement exists. The model results documented that thickness variation of intermediate decollement levels could explain complex and different folding styles in natural examples which must be taken into account for hydrocarbon exploration throughout these areas.

  13. Discrimination Study on Fluid—Rock Interaction Between Metallogenic and Non—Metallogenic Sections in a Shear Zone

    Institute of Scientific and Technical Information of China (English)

    魏俊浩; 李建威; 等

    1999-01-01

    Discriminations in a local chemical,fluidal,mechanical and thermal processes in a shear zone will lead to metallogenic differentiation in a local section.This paper,based on the general geological setting of the Shibangou gold deposit in Xixia,Henan,deals with petrological and petrochemical samples of altered rocks in the metallogenic section and of mylonites in the non-metallogenic section of a selected shear zone.The discriminations in fluid-rock interaction and petrological mass balance between altered rocks near the orebody and mylonites in the shear zone are discussed as well.The results show that the petrological volume of altered rocks in the metallogenic section of the shear zone is almost always dilatant and the mylonite volume in the non-metallogenic section is almost always lost.Major elements in altered rocks from the metallogenic section and in mylonites from the non-metallogenic section always show a tendency of being enriched and depleted,respectively.Fluid-rock ratios in the mylonites(Nu=93.68-468.40)are larger than those of the altered rocks(NC(Ⅳ)s=36.11-216.67).The gain and loss of major and trace elements from the altered rocks and mylonites in the shear zone are a composite process to be imported and exported by percolating fluids as well as of the loss and dilatancy of rock volume.

  14. Iron mineralization at the Songhu deposit, Chinese Western Tianshan: a type locality with regional metallogenic implications

    Science.gov (United States)

    Wang, Chun-Long; Wang, Yi-Tian; Dong, Lian-Hui; Qin, Ke-Zhang; Evans, Noreen J.; Zhang, Bing; Ren, Yi

    2017-06-01

    Hosted by volcaniclastics of the Carboniferous Dahalajunshan Formation, the Songhu iron deposit is located in the central segment of the Awulale metallogenic belt, Chinese Western Tianshan. Mineralization and alteration are structurally controlled by orogen-parallel NWW-striking faults. Integrating with mineralogical and stable isotopic analyses based on paragenetic relationships, two types of iron mineralization have been identified. The deuteric mineralization (Type I) represented by brecciated, banded, and disseminated-vein ores juxtaposed with potassic-calcic alteration in the inner zone, which was formed from a magmatic fluid generated during the late stages of regional volcanism. In contrast, the volcanic-hydrothermal mineralization (Type II) is characterized by hydrothermal features occurring in massive and agglomerated ores with abundant sulfides, and was generated from the magmatic fluid with seawater contamination. Two volcaniclastic samples from the hanging and footwall of the main orebody yield zircon U-Pb ages of 327.8 ± 3.1 and 332.0 ± 2.0 Ma, respectively, which indicate Middle Carboniferous volcanism. Timing for iron mineralization can be broadly placed in the same epoch. By reviewing geological, mineralogical, and geochemical features of the primary iron deposits in the Awulale metallogenic belt, we propose that the two types of iron mineralization in the Songhu iron deposit are representative regionally. A summary of available geochronological data reveals Middle-Late Carboniferous polycyclic ore-related volcanism, and nearly contemporaneous iron mineralization along the belt. Furthermore, petro-geochemistry of volcanic-volcaniclastic host rocks indicates that partial melting of a metasomatized mantle wedge under a continental arc setting could have triggered the continuous volcanic activities and associated metallogenesis.

  15. Different stages of chemical alteration on metabasaltic rocks in the subduction channel: Evidence from the Western Tianshan metamorphic belt, NW China

    Science.gov (United States)

    Xiao, Yuanyuan; Niu, Yaoling; Wang, Kuo-Lung; Iizuka, Yoshiyuki; Lin, Jinyan; Wang, Dong; Tan, Yulong; Wang, Guodong

    2017-09-01

    To understand the geochemistry of subduction zone metamorphism, especially the large-scale mass transfer at forearc to subarc depths, we carried out a detailed study of a ∼1.5 m size metabasaltic block with well-preserved pillow structures from the Chinese Western Tianshan high- to ultrahigh-pressure metamorphic belt. This metabasaltic block is characterized by omphacite-rich interiors gradually surrounded by abundant channelized (veins) glaucophane-rich patches toward the rims. The glaucophane-rich rims share the same peak metamorphic conditions with omphacite-rich interiors, but have experienced stronger blueschist-facies overprinting during exhumation. Representative samples from the glaucophane-rich rims and omphacite-rich interiors yield a well-defined Rb-Sr isochron age of 307 ± 23 Ma, likely representing this overprinting event. Both glaucophane-rich rims and omphacite-rich interiors show elevated K-Rb-Cs-Ba-Pb-Sr contents relative to their protolith, reflecting a large-scale enrichment of these elements and formation of abundant phengite during subduction. Compared with the omphacite-rich interiors, the glaucophane-rich rims have gained rare earth elements (REEs, >25%), U-Th (∼75%), Pb-Sr (>100%) and some transition metals like Co and Ni (25-50%), but lost P (∼75%), Na (>25%), Li and Be (∼50%); K-Rb-Cs-Ba show only 10% loss. These chemical changes would be caused by serpentinite-derived fluids during the exhumation in the subduction channel. Therefore, there are two stages of fluid action in the subduction channel. As the formation of phengite stabilizes K-Rb-Cs-Ba at the first stage, the residual fluids released from the phengite-rich metabasaltic rocks would be depleted in these elements, which are unlikely to contribute to elevated contents of these elements in arc magmas if phengite remains stable at subarc depths. In addition, the decrease of U/Pb ratios as the preferred enrichment of Pb over U in the eclogitic rocks during the first stage

  16. Origin and evolution of ore-forming fluids in the Hemushan magnetite-apatite deposit, Anhui Province, Eastern China, and their metallogenic significance

    Science.gov (United States)

    Luo, Gan; Zhang, Zhiyu; Du, Yangsong; Pang, Zhenshan; Zhang, Yanwen; Jiang, Yongwei

    2015-12-01

    The Middle-Lower Yangtze River Metallogenic Belt in the northern Yangtze Block is one of the most important economic mineral districts in China. The Hemushan deposit is a medium-class Fe deposit located in the southern part of the Ningwu iron ore district of the Middle-Lower Yangtze River Metallogenic Belt. The Fe-orebodies are mainly hosted in the contact zone between diorite and Triassic marble. The actinolite-phlogopite-apatite-magnetite ore shows metasomatic/filling textures and disseminated/mesh-vein structures. Based on evidences and petrographic observations, the ore-forming process can be divided into three distinct periods-the early metallogenic period (albite-diopside stage), the middle metallogenic period (magnetite stage and hematite stage), and the late metallogenic period (quartz-pyrite stage and carbonate stage). Fluid inclusion studies show four types of inclusions: type I daughter mineral-bearing three-phase inclusions (L + V + S), type II vapor-rich two-phase inclusions (L + V), type III liquid-rich two phase inclusions (L + V), and minor type IV liquid-phase inclusions (L). Apatites from the magnetite stage contain type I, type II and type III inclusions; anhydrites from the hematite stage mainly contain abundant type II inclusions and relatively less type I inclusions; quartz and calcite from the late metallogenic stage are mainly characterized by type III inclusions. Laser Raman spectroscopy and microthermometry of fluid inclusions show that the ore-forming fluids broadly correspond to unsaturated NaCl-H2O system. From the magnetite stage to the carbonate stage, the ore-forming fluids evolved from moderate-high temperature (average 414 °C), moderate salinity (average 25.01 wt.% NaCl equiv.) conditions to low temperature (average 168 °C), low salinity (average 6.18 wt.% NaCl equiv.) conditions. Hydrogen and oxygen isotopic studies indicate that the ore-forming fluid during the early stage of middle metallogenic period was mainly of magmatic

  17. Carbon, oxygen, sulfur and lead isotope constraints on the ore source and metallogenesis of copper deposits in western Awulale Mountain metallogenic belt, Xinjiang%新疆阿吾拉勒成矿带西段铜矿床碳、氧、硫、铅同位素研究——成矿物质来源及成矿环境探讨

    Institute of Scientific and Technical Information of China (English)

    赵军; 张作衡; 刘晓阳; 刘敏; 张贺; 朱维娜

    2012-01-01

    western Awulale Mountain metallogenic belt include subvolanic rock-related Cu deposits (SVR) situated in the middle and southern area and intermediate-low temperature hydrother-mal vein-type Cu deposits (ILTHV) located in the northern area. This paper reports a detailed C, O, S and Pb isotopic investigation of three SVR deposits (No. 109, Qunjisayi and Qunji) and two ILTHV deposits (Nulasai and Qiongbulake) lying from south to north in the ore field. The sulfur isotopic compositions of the sulfides from the five deposits show distinct differences and systematic variations from south to north. The SVR deposits show small variation of δ34S values from + 3.4%o to +4.4%o (No. 109 deposit) and from - 1.6%o to 0.2%o (Qunjisayi and Qunji deposits). In contrast, the ILTHV deposits have large variation of S^S values from - 18%o to + 8.9%o. The carbon and oxygen isotope variations of the two types have similar sulfur isotope variation features. The SVR deposits show small variation of δ13C values from - 1.44%o to + 0.8%o and relatively large variation of δ18O values from + 11.87‰ to + 16.99‰. The ILTHV deposits have large variation of δ13C values from - 10.1% to -3.2% and relatively large variation of δ18O values from 9.63% to 16.27%. The Pb-isotopic composition of sulfides from ILTHV deposits indicate that they are normal-Pb mainly derived from the mantle. The Pb-isotope of sulfides from felisic SVR deposits is rich in radiogenetic Pb provided by the Precam-brian basement rock. The Pb-isotope of sulfides from basic SVR deposits is the mixed mantle-Pb and crust-Pb. In conclusion, the systematic variations of mineral source and ore-forming process from SVR deposits to ILTHV deposits reveal that the metallogenic environments in southern and northern copper belt are different and this dif-ference was probably related to the Permian rifting evolution. In the process of Permian rifting evolution, the different extents of the stretching structure in southern and northern copper

  18. Deep-seated structure and metallogenic dynamics of the Ailaoshan polymetallic mineralization concentration area, Yunnan Province, China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Ailaoshan poly-metallic mineralization concentrated area (MCA) consists of the well known Ailaoshan metallogenic belt and adjacent mineral districts and/or deposits. Located in an area of several complex and intersecting tectonic units, the Ailaoshan poly-metallic MCA is controlled by deep crustal and mantle tectonism. Through interpretation of remote sensing images, we identified a large ring structure system that surrounds the MCA. This ring structure encloses regional deep-crustal faults, ductile shear zones, geothermal anomalies, magmatic rocks, and the major mineral deposits, all of which are the reflections of deep tectonic geodynamics that have been long active in this area. Geophysical data indicate that the crust is comprised of relatively stable two or three layers, with some irregular lower-velocity belts. The Moho in the ring sutures occurs as an area of local uplift. There exists an obvious transitional zone between the crust and mantle boundaries. Asthenopheric mantle shows multi-layer upwelling, which indicates multiple events during different geological epochs. It is believed that these mantle events or pulses were responsible for the formation of the regional shear zones, magmatic rocks, and polymetallic orebodies. Furthermore, an integrated metallogenic dynamics model related to the asthenopheric upwelling pulses in the MCA is established, defining events as old as Late Paleozoic.

  19. Deep-seated structure and metallogenic dynamics of the Ailaoshan polymetallic mineralization concentration area, Yunnan Province, China

    Institute of Scientific and Technical Information of China (English)

    GE LiangSheng; DENG Jun; GUO XiaoDong; ZOU YiLin; LIU YinChun

    2009-01-01

    The Ailaoshan poly-metalllc mineralization concentrated area (MCA) consists of the well known Aileoshan metallogenic belt and adjacent mineral districts and/or deposits. Located in an area of sev-eral complex and intersecting tectonic units, the Ailaoshan poly-metallic MCA is controlled by deep crustal and mantle tectonism. Through interpretation of remote sensing images, we identified a large ring structure system that surrounds the MCA. This ring structure encloses regional deep-crustal faults, ductile shear zones, geothermal anomalies, magmatic rocks, and the major mineral deposits, all of which are the reflections of deep tectonic geodynamics that have been long active in this area. Geo-physical data indicate that the crust is comprised of relatively stable two or three layers, with some irregular lower-velocity belts. The Moho in the ring sutures occurs as an area of local uplift. There ex-lets an obvious transitional zone between the crust and mantle boundaries. Asthenopheric mantle shows multi-layer upwelling, which indicates multiple events during different geological epochs. It is believed that these mantle events or pulses were responsible for the formation of the regional shear zones, magmatic rocks, and polymetallic orebodies. Furthermore, an integrated metallogenic dynamics model related to the asthenopheric upwelling pulses in the MCA is established, defining events as old as Late Paleozoic.

  20. Magmatic Conduit Metallogenic System - A New Model for the Origin of Ore-deposits

    Science.gov (United States)

    Su, S.; Tang, Z.; Wu, G.; Deng, J.; Xiao, Q.; Luo, Z.; Cui, Y.

    2013-12-01

    occurs among the pyroxenes/amphiboles. The content of titanium in the iron ores changes from 0.14% to 0.20 wt. % gradually from southeast to northwest (NW), suggesting the direction of melt-fluid flow bearing iron is from SE to NW. These characteristics in the Xishimen iron deposit indicate that melt-fluid flow bearing iron controls the distribution of iron orebodies. Several key points in 'Magmatic Conduit Metallogenic System' are concluded here: 1. All melt or melt-fluid bearing metals formed in the staging chamber are finally settled in the conduits based on their differences in density; 2. We can determine the direction of the melt or melt-fluid flow according to the content and textures of ores in the conduits. We propose that 'Magmatic Conduit Metallogenic System' could serve as a new exploring model for the ore-deposits connected with intrusions.

  1. Geological and geochemical character and genesis of the Jinlongshan-Qiuling gold deposits in Qinling orogen: Metallogenic mechanism of the Qinling-pattern Carlin-type gold deposits

    Institute of Scientific and Technical Information of China (English)

    张复新,陈衍景,李超Department; of; Geology,; Peking; University,; Beijing; 100871,; China; ,张静Department; of; Geology,; Peking; University,; Beijing; 100871,; China; ,马建秦,李欣Department; of; Geology,; Peking; University,; Beijing; 100871,; China

    2000-01-01

    The Qinling Carlin-type gold deposit belt is the second largest Carlin-type gold ore concentrated area in the world and occurs in Mesozoic intracontinental collisional orogen, contrasting to the Carlin-type gold deposits in the Basin and Range province in Cenozoic active continental margin of West America. With ore-forming ages focussed at the range of 197.45-129.45 Ma, its metallogenic geodynamic background was the decornpression-pyrogenation regime at the transition stage from collisional compression to extension, indicating that gold mineralization synchronized with the Mesozoic continental collision. Geochemical studies discover that ore fluids and materials mainly came from the Hercynian-lndosinian tectonic layer. Mesozoic intracontinental subduction of Hercynian-lndosinian association along the Shuanghe-Gongguan fault led to the formation of Jinlongshan-Qiuling gold deposits. Accordingly, the tectonic metallogenic model is established for Qinling-pattern Carlin-type gold deposits.

  2. Discovery and Significance of Carbonate Mud Mounds from Cu-polymetallic Deposits in the Middle and Lower Yangtze Metallogenic Belt:Examples from the Wushan and Dongguashan Deposits%长江中下游成矿带铜多金属矿床中灰泥丘的发现及其意义——以武山和冬瓜山铜矿为例

    Institute of Scientific and Technical Information of China (English)

    蒋少涌; 丁清峰; 杨水源; 朱志勇; 孙明志; 孙岩; 边立曾

    2011-01-01

    Bedded sulfide orebodies occur in the Wushan and Dongguashan Cu deposits in the Middle and Lower Yangtze mineralization belt. In this study, we found a typical circular or laminated texture in the bedded sulfide ores. Based on microscopic observation of thin sections of the ore samples, carbon and oxygen isotopic analysis, and scanning electron microscope (SEM) observation, we suggested that this type of sulfide ores belongs to a mineralized kind of carbonate mud mound. The macroscopic structures of these sulfide ores are quite similar to those of cavities system of typical carbonate mud mounds, and there are also bacteria structures found in some of the ore samples with SEM analysis. Previous studies show that the carbonate mud mound generally develops in a slope setting with water depth deeper than platform. It is also shown that the occurrence of carbonate mud mound has a close relationship with sea-floor hydrothermal exhalative ore-forming processes. The conservation conditions of the carbonate mud mounds in the two copper deposits are different, in the Dongguashan Cu deposit a lot of primary exhalative sedimentary textures are preserved, bacteria structures are found, and the carbon-oxygen isotopic compositions show primary sedimentary characteristics, while those in the Wushan Cu deposit show hydrothermal altered/overprinted textures, and no bacteria structures have been found so far, the carbon-oxygen isotopic compositions also indicate a hydrothermal reworking. In summary, the discoveries of carbonate mud mounds structure sulfide ores in the Wushan and Dongguashan Cu deposits provide new evidence for the Hercynian sedimentary hydrothermal-exhalative mineralization in the Middle and Lower Yangtze metallogenic belt.%通过对长江中下游成矿带中武山铜矿和冬瓜山铜矿层状硫化物矿体的详细研究,发现了大量具有层圈状构造、层纹状构造或不规则同心环状构造的矿石.在前人研究基础

  3. Metallogenic Prediction Between Lumwana and Nomwana of Northwest Province in Zambia%赞比亚西北省卢姆瓦纳-诺姆瓦纳间成矿预测

    Institute of Scientific and Technical Information of China (English)

    李富昌

    2014-01-01

    卢姆瓦纳-诺姆瓦纳工作区位于赞比亚西北省,大地构造位置位于赞比亚最重要的铜矿成矿带-卢菲利安(Lufilian)褶皱带的西端,与褶皱带的地质发展经历较相似。同时,卢姆瓦纳区处于总体呈北东向分布的卡波姆坡(kabombo )穹窿上,根据工作区的地质条件,区域铜矿带的成矿规律及分布特征,借鉴相邻区域的一些资料解译情况,通过对比分析,对卢姆瓦纳-诺姆瓦纳工作区进行铜、钴矿成矿预测,以利于进一步正确研判该区的找矿前景。%Lumwana - nomwana work area is located in the northwest province of Zambia .The geotectonic position is in the western end of Lufilian fold belt which is the most important copper metallogenic belt in Zambia , similar to the geological development experience of the fold belt . Lumwana is on the "kabombo"fornix that distributes in northeast . According to the comparative analysis of the geological condition , the metallogenic regularity and distribution features of the regional metallogenic belt , this paper states the copper and cobalt ore metallogenic prognosis for Lumwana - nomwana work area in order to correctly judge the prospecting potential furtherly .

  4. Cenozoic evolution of tectono-fluid and metallogenic process in Lanping Basin,western Yunnan Province, Southwest China: Constraints from apatite fission track data

    Institute of Scientific and Technical Information of China (English)

    LI Xiaoming; SONG Yougui

    2006-01-01

    Since the Mesozoic, abundant metal and salt deposits have been formed in the Lanping Basin, western Yunnan Province, Southwest China, constituting a well-known hydrothermal ore belt in China. Most of the deposits are meso-epithermal hydrothermal deposits. This paper preliminarily deals with the mineralization ages of hydrothermal deposits in the Lanping Basin by using the apatite fission track method, and integrates the spatial distribution of the deposits and their regional geological backgrounds, to give the preliminary viewpoints as follows: (1) the apatite fission track ages acquired range from 19.9 Ma to 52.8 Ma, much younger than those of their host strata, so they may be considered to be mineralization ages, which represent the late mineralization period; (2) the apatite fission track ages tend to become younger from the west to the middle of the basin, indicating that the latest evolution of tectono-fluid and/or metallogenic processes of the middle basin ended later than that in the west; (3) in the Paleogene, most of the Cu deposits were formed in the western part of the basin; (4) the major metallogenic processes occur between the Paleogene and the Neogene, because the eastern and western edges of the basin were subducted into and collided with its bilateral continental blocks, respectively, and the central fault was strongly activated, which led to the processes of large-scale ore-forming fluids, and their differentiation and transport because of the variation of their physical and chemical properties. Having been squeezed and uplifted, the Lanping Basin became an intermontane basin that contains many kinds of fluid traps resulting in the formation of different types of ore deposits (for example, Pb-Zn, Cu, Ag) of different scales in the middle of the basin. Simultaneously, the fluids with volatile elements such as Hg, Sb and As were transported upwards along the central fault system and diffused into its subordinate fractures, thus leading to the

  5. Metallogenic Districts of Yangtze Cratonic Rim at the Edge of Chaos

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Combining the science of complexity with ore geology, the author puts forward a new theory of metallogenesis: "complexity and self-organized criticality of metallogenic dynamic systems", and three fundamental theories are raised for it. The ore genesis and regularity of ore formation of four metallogenic districts around the Yangtze craton in China are studied with this theory. It is found that"metallogenic districts of Yangtze cratonic rim are all at the edge of chaos". This proposition is expounded by four determinative criteria of the edge of chaos for metallogenic districts of Yangtze cratonic rim.

  6. Influence of supercontinent cyclicity on global metallogenic processes: Main tendencies

    Science.gov (United States)

    Tkachev, A. V.; Rundquist, D. V.

    2016-08-01

    The distribution of large and superlarge mineral deposits (LSMD) of the most important raw materials is correlated with supercontinent cycles in the geological history of the Earth. The latter displays the distinct correlation between metallogenic activity and cyclic global endogenous processes reflected in quasi-regular cycles, which result eventually in the assembly and breakup of supercontinents. In the framework of these cycles, the maximums in the LSMD assembly coincide with periods of intense growth of the subcontinent crust owing to growth of the matter originated from juvenile sources (Kenoran, Columbian cycles) or with epochs of intense recycling of the mature crust (Pangean, Amasian cycles). The Rodinian cycle with minimum activity of these both endogenous processes demonstrates simultaneously minimum metallogenic activity. The distribution of most LSMD types generally follows these main tendencies.

  7. Comment on "The Late Devonian Variscan suture of the Iberian Massif: A correlation of high-pressure belts in NW and SW Iberia. Tectonophysics 654, 96-100" by R. Fernández and R. Arenas

    Science.gov (United States)

    Simancas, J. F.; Azor, A.; Martínez Poyatos, D. J.; Expósito, I.; Pérez-Cáceres, I.; González Lodeiro, F.

    2016-01-01

    A vast Variscan nappe spreading from the Allochthonous Complexes of NW Iberia to the Ossa-Morena Zone in SW Iberia has been proposed by Díez Fernández and Arenas (2015), based on the correlation of different outcrops of high-pressure and MORB-type rocks. This interpretation conflicts with well-known geological and geophysical data regarding the SW Iberian Variscides, which point to: i) major kinematic and geometric inconsistencies come up when interpreting the Ossa-Morena Zone as an allochthonous unit, ii) the outcrops of high-pressure and MORB-type rocks belong to two different sutures rather than a single one, and iii) SW Iberia is characterized by transpressional deformation related to a very oblique left-lateral continental collision, while NW Iberia features a rather frontal collision.

  8. DYNAMIC SYSTEM COLLISION,SUPERIMPOSING AND GOLD DEPOSIT FORMING IN JIAPIGOU FAULT BELT,JILIN PROVINCE%吉林夹皮沟断裂带动力系统碰撞、叠加及金矿床形成

    Institute of Scientific and Technical Information of China (English)

    孙忠实; 冯本智; 邓军; 翟裕生

    2001-01-01

    Dynamic system is the sdudying key in gold metallization. Itcontrols gold deposit forming all the time. Earth evolution and gold metallization in Jiapigou area are divided into three stages and three kinds of tectonic belts with the help of metallogenic dynamic system theory. The first one is the marginal gold mineralizing belt of rising-slipping dynamic system in the Archean-Proterozoic craton. A pair of dynamic system between uplifting Archean craton and extending or slipping Proterozoic sediments formed gold mineralizing ductile shear belts of the craton margin and then gold enriched initially. Dynamic system of the hercynian subduction is the second kind of the south margin mineralizing belt. Continental rift and collision took place between Siberia plate and Chinese-Korea plate. The positive-negative dynamic system formed over earth crust-fault and gold mineralizes.The Mesozoic superimposing tectono-magmatic dynamic system forms the third kind of metallogenic belt. The Mesozoic Pacific plate subduction, TanLu fault slipping , NNE and NW striked conjugate ore-controlling structure form poly-level dynamic system superimposing. Magma activities and mantle origin fluid go up. Gold further enrich. Finally form Jiapigou gold deposit.The limits of metallogenic prognosis are that original metamorphic rock's area enter Jiapigou fault belt and the Mesozoic granite area by both sides of Jiapigou fault.%动力系统是金成矿作用研究的关键,它控制金矿床产生的始终。运用成矿动力系统思想把夹皮沟区地壳演化和金成矿分为三大阶段和三大构造带。(1)太古—元古宙克拉通隆—滑动力系统边缘矿化带,太古宙克拉通隆起、元古宙沉积物拉伸滑断,成矿动力系统在克拉通周边形成韧性剪切带,金受到初步富集;(2)海西俯冲动力系统南缘矿化带,西伯利亚板块与中朝板块间大陆拉张和碰撞,正反动力系统产生超壳断裂和金矿化;(3)中生代叠

  9. The characteristics, origins, and geodynamic settings of supergiant gold metallogenic provinces

    Institute of Scientific and Technical Information of China (English)

    Robert; Kerrich[1; Richard; Goldfarb[2; David; Groves[3; Steven; Garwin[4

    2000-01-01

    There are six distinct classes of gold deposits, each represented by metallogenic provinces, having 100’s to > 1 000 tonne gold production. The deposit classes are: (1) erogenic gold; (2) Carlin and Carlin-like gold deposits; (3) epithermal gold-silver deposits; (4) copper-gold porphyry deposits; (5) iron-oxide copper-gold deposits; and (6) gold-rich volcanic hosted massive sul-fide (VMS) to sedimentary exhalative (SEDEX) deposits. This classification is based on ore and alteration mineral assemblages; ore and alteration metal budgets; ore fluid pressure(s) and compositions; crustal depth or depth ranges of formation; relationship to structures and/or magmatic intrusions at a variety of scales; and relationship to the P-T-t evolution of the host terrane. These classes reflect distinct geodynamic settings. Orogenic gold deposits are generated at mid-crustal (4-16 km) levels proximal to terrane boundaries, in transpressional subduction-accretion complexes of Cordilleran style erogenic belts; other orogeni

  10. Rare earth element geochemical constrains on metallogeny of Jiapigou gold belt, Northeast China

    Institute of Scientific and Technical Information of China (English)

    HUANG Zhixin; YUAN Wanming; YU Haijun

    2012-01-01

    Analyses of rare earth dements (REE) in gold-bearing quartz vein,granite and altered wall-rock (amphibolite) collected from Jiapigou gold belt in Southeast Jilin Province were conducted using inductively coupled plasma-mass-spectrometry (ICP-MS).The results indicated that the Jiapigou gold belt underwent two periods of gold mineralization:the earlier mineralization was related to the intrusion of Neoarchaean kaligranite,where the REE of earlier gold-bearing quartz veins and Neoarchaean kaligranites were typically featured by lower concentration and positive Eu anomaly; the later mineralization was related to the intrusion of the Yanshanian granite in Mesozoic,where the REE of later gold-bearing quartz veins and Yanshanian granites were typically featured by high concentration and negative Eu anomaly.However,the metallogenic mechanisms of the earlier and of the later gold mineralization periods were analogous,metallogenic materials were heterogenous with metallogenic fluids which mainly originated from magmatic hydrothermal fluids,mixed with metamorphic fluids; the metallogenic materials were mainly derived from the altered wall rock.

  11. CRED REA Coral Population Parameters at Necker, NW Hawaiian Islands (NWHI) in 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 2 sites at Necker in the NW...

  12. CRED REA Coral Population Parameters at Kure Atoll, NW Hawaiian Islands (NWHI), 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Kure Atoll in the NW...

  13. STRUCTURAL EVOLUTION AND METALLOGENY OF SOUTH XINJIANG METALLOGENIC BELT,JIANGXI,SOUTH CHINA

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    STRUCTURALEVOLUTIONANDMETALLOGENYOFSOUTHXINJIANGMETALLOGENICBELT,JIANGXI,SOUTHCHINALiuJishunWuYanzhiLiPeizheng(DepartmentofGe...

  14. Formation conditions of the Rudny Altai metallogenic province

    Science.gov (United States)

    Kozlov, M. S.

    2015-07-01

    The results of previous geological, petrochemical, and metallogenic surveys conducted from the 1960s to the 1990s provide the geological and tectonic basis of this study. The unique mineral deposits of the Rudny Altai metallogenic province were formed in the Middle Paleozoic (S2-C1) at the junction between different structures of the Altai-Mongolian terrane: the Alei-Charysh-Tigirek rift (in the north) with the Korgon-Markakol' island arc and Belaya Uba-Maimyr intra-arc trough (in the southwest). The Rudny Altai structural-formational zone that formed at the junction between these structures evolved as a magmatic arc and was characterized by the formation of granite-greenschist arches, volcanoplutonic magmatism and high heat and fluid flow (greenschist-facies metamorphism of Upper Silurian-Upper Devonian rocks and deposition of pyrite-bearing hydrothermal-sedimentary horizons, VMS and copper-VMS deposits and isolated base-metal ore bodies). The tectonomagmatic history of the Rudny Altai zone can be subdivided into several stages: Ludlow-Emsian, Late Emsian-Givetian, Frasnian-Early Famennian, Middle Famennian-Early Visean, and Late Visean-Serpukhovian. The island arc is represented by volcanic rocks of the andesite-dacite-rhyolite (early stage), basalt-rhyolite (Late Emsian-Eifelian), and basalt-andesite-rhyolite series (Late Visean). Volcanosedimentary strata (until the Givetian age) and turbidites up to 3-5 km thick were deposited in the interarc trough. Because of their metastable behavior, the volcanic rocks became actively involved in ion-exchange reactions with the formational waters, whereas the differences in hydraulic head between arches and troughs created favorable conditions for the transport of the metamorphic fluids, and the thermal gradient promoted thermodiffusion of divalent species of Mg, Pb, Zn, Cu, etc. toward the high-temperature zone and development of the high-Mg metamorphic-metasomatic alteration with a VMS-base-metal mineralization. As a

  15. Reviews and new metallogenic models of mineral deposits in South China: An introduction

    Science.gov (United States)

    Hu, Rui-Zhong; Chen, Wei Terry; Xu, De-Ru; Zhou, Mei-Fu

    2017-04-01

    In South China, the Yangtze and Cathaysia blocks were welded together along the Jiangnan Fold Belt during Neoproterozoic time (∼830 Ma). Large-scale mineralization in these two blocks occurred from Proterozoic to Cenozoic, making the region one of the most important polymetallic metallogenic provinces in the world. Of particular importance are world-class deposits of iron-oxide copper gold (IOCG), sediment-hosted Mn-P-Al-(Ni, Mo, PGE), syenite-carbonatite-related REE, felsic intrusion-related Sn-W-Mo-Cu-Fe-Pb-Zn, mafic intrusion-related V-Ti-Fe and Cu-Ni-PGE and low-temperature hydrothermal Pb, Zn, Au, and Sb (Fig. 1). In addition, the Ta-Nb, Hg, As, Tl and U deposits in South China are among the world largest of these kinds. Because of these deposits, South China has been a focus of researches for many years. Publications before 2005 were mostly restricted in Chinese. In the past decade, some case studies on some world-class deposits in South China are available in international journals. These recent studies have advanced our understanding of their mode of formation. However, some important issues regarding the timing, tectonic setting and mechanisms of metal concentration still remain poorly understood. This special issue brings together some of the latest information on these topics, including major review papers on specific types of mineralization and several papers dealing with some specific deposits in the region. We anticipate that this issue will generate more interests in the studies of mineral deposits in South China. In this introduction, we outline the tectonic framework and associated deposits.

  16. Paleozoic magmatism and metamorphism in the Central Tianshan block revealed by U-Pb and Lu-Hf isotope studies of detrital zircons from the South Tianshan belt, NW China

    Science.gov (United States)

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

    2015-09-01

    As a major Precambrian microcontinent in the southernmost Central Asian Orogenic Belt (CAOB), the Central Tianshan block (CTS) in the Chinese Tianshan is essential for understanding the final assembly of the southern CAOB. It experienced multistage Paleozoic magmatism and metamorphism, but the detailed processes are still controversial and far from being completely understood. This paper reports coupled U-Pb and Lu-Hf isotopic data of detrital zircons from late Paleozoic (meta-)sedimentary strata in the South Tianshan belt, which can provide new insight into deciphering the Paleozoic evolution of the eastern segment of the CTS block. Characterized by typical oscillatory zoning and high Th/U ratios (> 0.2), detrital zircons in the Permian sedimentary samples yield dominant age populations at ca. 505-490 Ma, 475-440 Ma, 430-400 Ma and 340-250 Ma, pinpointing the development of four episodes of magmatism in the eastern CTS block. Particularly, Ordovician-Silurian (475-440 Ma) zircons, possessing low negative εHf(t) values, predominate in sedimentary strata in and surrounding the CTS block, indicating that the 475-440 Ma magmatic rocks probably constitute the main body of the CTS block. The origin of this (early Paleozoic) episode of magmatism was most likely related to the southward subduction of the Junggar Ocean beneath the CTS block. Carboniferous-Triassic (340-250 Ma) zircons have dominantly positive εHf(t) values, probably derived from the post-collisional juvenile rocks in the CTS block. Combined with previous studies, our data suggest that the single source terrane for the sampled strata was the CTS block, which had been a topographic high providing substantial detritus to the surrounding areas at least since the Early Permian. In the metasedimentary sample, detrital zircons mostly show partially/fully recrystallized internal textures and low Th/U ratios (isotopes and Ti-in-zircon thermometer of metamorphic zircons in this study, as well as previous

  17. 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.

  18. Belt conveyer

    Energy Technology Data Exchange (ETDEWEB)

    Cwieczek, A.; Dembinski, C.

    1982-04-30

    The patented belt conveyor is distinguished by the fact that the rate of motion of the belt changes smoothly depending on the load: the greater the load the higher the rate. This makes it possible to prolong the service life of the belt, i.e., during idling of the conveyor it is exposed to deformation on the drive and tension drums a fewer number of times. The essence of the invention is based on the use for driving the drum of a friction transmission. One of the elements of this transmission is the drive drum of the conveyor, and the other is the drive wheel which is pressed to the inner (or outer) surface of the drum. Change in rotation velocity of the drum is reached by changing the diameter of the drive wheel. The rim of the latter has an elastic tire to which compressed air is fed. The diameter of the drive wheel depends on the quantity of air in the tire. It is set automatically by a regulating system depending on the conveyor load. Variants are patented for the belt conveyor which is distinguished by the design of the friction transmission. It contains 1, 2 or more drive wheels. It can have a cylindrical or conical inner surface of the drive drum, etc.

  19. Metallogenic epoch and genesis of the gold deposits in Jiaodong Peninsula, Eastern China: a regional review

    Institute of Scientific and Technical Information of China (English)

    YANG Liqiang; DENG Jun; GE Liangsheng; WANG Qingfei; ZHANG Jing; GAO Bangfei; JIANG Shaoqing; XU Hao

    2007-01-01

    Gold deposits are characterized by multi-sources, superimposition, large scale and temporal-spatial concentration in Jiaodong Peninsula, Eastern China. In this paper, we review the history and the development of the study on metallogenic chronology and genesis of gold deposits, summarize the main features of superimposed metallogenesis, provide evidence of the Mesozoic complex metallogenic system, and point out some problems for further research of Jiaodong gold deposit cluster from a regional view. Although gold deposits are different in genetic types, ore-forming materials and geological settings, our research indicates that the accumulation and emplacement of the ore-forming materials are temporally-spatially concentrated on a large scale, and the main metallogenic epoch of Jiaodong gold deposits was concentrated in Mesozoic. Metallogenic chronology and geological-geochemical data indicate that there are two periods of gold mineralizations occurred in 130-110 Ma and 90-80 Ma respectively in Jiaodong ore cluster. The gold deposit cluster results from the superimposition of the polygenetic mineralization, and further study is needed to investigate the formation and evolution of the Mesozoic complex metallogenic system.

  20. Late Paleozoic tectonic evolution and concentrated mineralization in Balkhash and West Junggar, western part of the Central Asian Orogenic Belt

    Science.gov (United States)

    Dong, Shuwen; Chen, Xuanhua; Chen, Zhengle

    2016-04-01

    The Central Asia Orogenic Belt (CAOB) is an important area with significant growth of the crust and metallogeny in the Late Paleozoic. The Balkhash-Junggar tectono-metallogenic belt consists of the Balkhash, the West Junggar, and the East Junggar tectono-metallogenic belts in western part of the Central Asian Orogenic Belt (CAOB). According to the structural geological relationship, the East Junggar, the West Junggar, and the Balkhash belts are considered to be once a continuous E-W-trending tectono-metallogenic belt in Late Carboniferous. The West Junggar belt is featured with NE-trending left-lateral strike-slip faulting tectonic system (WJTS), while the left-lateral strike-slip faults are E-W-trending in the Balkhash belt. The WJTS consists of the Darabut, the Mayile, and the Baerluke faults, and the blocks among them. All these left-lateral strike-slip faults are forming due to the transition of tectonic settings from syn-collisional orogeny to post-collisional extension during the closure of the ocean (the Junggar Sea) in Late Carboniferous, with significant intrusion of batholiths and crust growth occurred in this period. These faults are truncated by the right-lateral strike-slip faults, such as the Chingiz-Junggar fault, and the Central Balkhash fault in Mesozoic. The Balkhash-Junggar tectono-metallogenic belt is important for the occurrence of many well-known super-large and large porphyry Cu-Mo deposits (such as the Kounrad, the Aktogai, the Borly, and the Baogutu deposits), large skarn Cu deposits (in the Sayak ore-filed), large rare metal deposits (such as the East Kounrad, the Zhanet, and the Akshatau deposits), and large gold deposits (such as the Hatu deposit). Zircon U-Pb ages, Re-Os isotopic dating of molybdenites, 40Ar/39Ar thermochronology of hornblendes, muscovites, biotites, and K-feldspars, and zircon and apatite fission track (FT) and (U-Th)/He dating and thermal history modeling, provide a multidisciplinary approach to constrain the whole

  1. 全球成矿域和成矿区带%Global metallogenic domains and districts

    Institute of Scientific and Technical Information of China (English)

    梅燕雄; 裴荣富; 杨德凤; 戴自希; 李进文; 徐丛荣; 瞿泓滢

    2009-01-01

    作者在编制1:2 500万世界大型超大型矿床成矿图的基础上,根据全球地质构造背景与成矿特征,划分出劳亚、冈瓦纳、特提斯、环太平洋4大成矿域和北美、格陵兰、欧洲、乌拉尔-蒙古、西伯利亚、中朝、南美、非洲-阿拉伯、印度、澳大利亚、加勒比、地中海、西亚、喜马拉雅、中南半岛、北科迪勒拉、安第斯、楚科奇-鄂霍茨克、东亚、伊里安-新丙兰、南极等21个巨型成矿区带,简要论述了各成矿域和成矿区带的成矿特征,首次构建了全球成矿体系.%Large and superlarge mineral deposits have abundant mineral reserves and special metallogenic characteristics as well as considerable economic value and strategic significance. According to rough estimates, large and superlarge mineral deposits only account for 5 % ~ 10 % of the total deposits but provide 30 % ~ 50 % of the world' s mineral resources/reserves. They play a decisive role in the sustainable economic and social development in a certain country or even in the whole world. The World Metallogenic Map of Large and Superlarge Mineral Deposits on the scale of 1:25 000 000 was compiled by Pei Rongfu, D. V. Rundquist, Mei Yanxiong and some others in 2006 and published by the Geological Publishing House in 2009. In the map, three major categories of mineral resources (energy mineral resources, metallic mineral resources and nonmetallic mineral resources), 22 minerals and 445 large and superlarge mineral deposits are plotted. According to the global geological tectonic settings and metallogenic characteristics, four metallogenic domains, namely, Laurasia, Gondwana, Tethys and circum-Pacific, and 21 gigantic metallogenic districts, have been distinguished. Located in the northern part of the earth, the Laurasia metallogenic domain traverses North America, Europe and Asia and is composed of six gigantic metallogenic districts, i.e., North America, Greenland, Europe, Ural

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

    Indian Academy of Sciences (India)

    G Ramadass; D Himabindu; N Srinivasulu

    2003-12-01

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

  3. Kinematic and structural controls of Au metallogenic systems in the Early Earth: Examples from the eastern Pilbara Craton, NW Australia

    NARCIS (Netherlands)

    Guerreiro, F.M.

    2004-01-01

    This thesis is divided into eight chapters excluding the Introduction (Chapter 1):- Literature Review: Chapter 2 provides a detailed overview of the historical mining activities within the East Pilbara Superterrain. Details such gold production, grades and mining techniques are described, together w

  4. Metallogenic evolution of uranium deposits in the Middle East and North Africa deposits

    Science.gov (United States)

    Howari, Fares; Goodell, Philip; Salman, Abdulaty

    2016-02-01

    This paper is briefly involved in classification and distributions of the Middle East and North Africa (MENA) uranium deposits. The study of these mineral systems can significantly contribute to our further understanding of the metallogeny of known and poorly explored deposits. This provides contribution to, and further enhancement of, current classifications and metallogenic models of uranium systems, allowing researchers to emphasize on unknown or poorly studied mineral systems found in MENA. The present study identified eight metallogenic types of uranium associated with: 1) the Archean rocks and intra-cratonic basins, 2) the Pan-African granites and rhyolites which are characterized by igneous activity, 3) Phanerozoic (Paleozoic) clastics, these deposits are the sedimentological response to Pan African magmatism, 4) Mesozoic (basal) clastics type e.g. Nubia sandstones which are characterized by uranium minerals, 5) regional sedimentary phosphate deposits which are categorized as geosynclinal, or continental margin deposits, on the shelf of the Tethys Ocean, 6) Cenozoic Intracratonic Felsic Magmatism of the Tibesti and Hoggar, and the sandstone U deposits of adjoining Niger. These are similar to the Pan-African magmatism metallogenic, 7) Calcretes, and 8) Resistate minerals which are often enriched in rare earth elements, sometimes including uranium. They are thus sometimes considered as U resources but poorly explored in the MENA region. These metallogenic types are described and discussed in the current paper.

  5. Metallogenic Features and Metalogenic Model of Laterite Gold Deposits in Southern China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The modern laterite gold deposits in southern China, which belong to reworked laterite deposits, can be further divided into three subclasses and seven types. Their geological features, ore-forming conditions and regularities are discussed. A geologic-geochemical metallogenic model for laterite gold deposits has been established.

  6. 湖南魏家隐伏型钨-萤石矿床控矿因素及成矿规律分析%Ore controlling factors and metallogenic regularity of concealed tungsten-fluorite deposits in Weijia of Hunan

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    魏家钨矿区位于南岭成矿带中段,为2010年国土资源大调查中新发现的矿产地。通过近年的工程控制,在钨矿体内新发现了萤石矿。本文在对矿床地质特征进行了进一步研究基础上,对矿床的控矿因素及成矿规律进行了总结分析,认为本矿区矿床类型为矽卡岩型钨、萤石矿床,矿体的空间展布主要受矿区内隐伏型层间破碎带和层间破碎带内充填的花岗斑岩脉共同控制。%Weijia tungsten mining area,a newly discovered mineral site in"The Grand Survey of Land and Re-sources of 2010",is located in the middle part of Nanling metallogenic belt.In recent years,fluorite ores were discovered in tungsten orebodies by ore-controlling projects.Based on further study on geological char-acteristics of the deposits,this paper summarizes and analyzes the ore-controlling factors and the metallogen-ic regularity of the deposits,and it shows that the deposits in this area are skarn-type tungsten-fluorite de-posits and the spatial distribution of the orebodies are primarily controlled by concealed interlayer fracture zone and granite porphyry veins filled with in the interlayer fracture zone.

  7. 加权Logistic回归模型在斑岩铜矿预测中的应用——以中—哈边境扎尔—玛萨吾尔成矿带为例%The Application of Weighted Logistic Regression Model in Prediction of Porphyry Copper Deposit——take Zharma-Sawur metallogenic belt, China-Kazakhstan border area, as an example

    Institute of Scientific and Technical Information of China (English)

    努丽曼古·阿不都克力木; 张晓帆; 陈川; 徐仕琪; 赵同阳

    2012-01-01

    加权Logistic回归是基于GIS成矿预测的主要方法之一,其模型是不同于线性模型的一种类型.它具有强大的空间分析功能、适用性强、不受任何独立条件的约束、预测结果更可靠,因此在矿产资源评价研究中得到了很多地质学家的青睐.以矿床模型和成矿理论为基础,加权Logistic回归分析模型在成矿预测中的应用主要包括三部分:加权Logistic回归模型的建立及其应用、成矿有利度综合评价、成矿远景区圈定.本文以中国—哈萨克斯坦边境地区扎尔玛—萨吾尔成矿带斑岩型铜矿为例,探讨了基于GIS的加权Logistic回归模型在成矿预测中的应用.%Weighted Logistic Regression is one of the main methods of mineral potential mapping. It is different from linear model. Because of its powerful spatial analysis function, strong adaptability, unconstrained by independent conditions, and more reliable prediction results, Weighted Logistic Regression is widely used by many geologists in mineral resources assessment. Based on the mineral deposit model and theory, Weighted Logistic Regression is consists of three parts: (1) Establishment of weighted logistic regression model for mineral potential mapping; (2 ) comprehensive evaluation of favorable degrees; (3 ) mineral potential mapping of study area. By the Weighted Logistic Regression model for mineral potential mapping, Zharma-Sawur Metallogic Belt which across border region of China and Kazakhstan is studied and mineral prospecting area of porphyry copper deposit is mapped. At the end, the availability of Weighted Logistic Regression Model for mineral potential mapping is discussed.

  8. Seat belt reminders.

    NARCIS (Netherlands)

    2008-01-01

    Seat belts are an effective way of reducing the number or road deaths and severe road injuries in crashes. Seat belt reminders warn car drivers and passengers if the seat belt is not fastened. This can be done by a visual signal or an acoustic signal or by a combination of the two. Seat belt reminde

  9. Tectonomagmatic Metallogenic System of Dexing Ore Field, Jiangxi, China

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    13 ore deposits and a large number of ore occurrences cluster in Dexing ore field which is 20 km long and 12 km wide. The tectonic evolution, magmatism, as well as the metallogeny are controlled by the Northeast Jiangxi deep-seated fracture belt (NJDFB). The source is believed to have been derived from the Meso-Neoproterozoic marine volcanism. The magmatic activity of Mesozoic I-type granite could have provided the metal elements, thermal fluid, heat, and the space for ore-forming processes. A unified geological model is proposed, which combines the tectonism, magmatism and metallogeny as the basic control of the giant metal mineralizations.

  10. Belt attachment and system

    Science.gov (United States)

    Schneider, Abraham D.; Davidson, Erick M.

    2016-02-02

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

  11. THE METALLOGENIC ENVIRONMENT AND POTENTIAL OF THE PORPHYRY COPPER IN XINJIANG%新疆斑岩铜矿的成矿条件和远景

    Institute of Scientific and Technical Information of China (English)

    刘德权; 唐延龄; 周汝洪

    2001-01-01

    Through the study on the geology and metallogenic environment ofthe giant Tuwu porphyry copper deposit in Hami to Jueluotag porphyry copper meatllogenic belt, it is concluded that those deposits formed in the active continental margin during the middle to late convergent stage of the orogenesis. Comparing with Pacific Rim porphyry copper belt, the favorite tectonic environment is "Andean", i.e., the fan shaped structure. It is also recognized that Xinjiang has the similar geological and metallgenic environment with the porphyry copper belts in adjacent countries and/or districts, and then there is good potential for finding large and giant porphyry copper deposits, especially in Western Tianshan, Western Kunlun, Muzitag, Qimantag, south of Eastern Jungger, etc. areas.%对哈密土屋地区斑岩铜矿和觉罗塔格斑岩铜矿成矿带的成矿地质条件进行了研究,其形成于造山带汇聚阶段中-后期的活动陆缘环境。与环太平洋斑岩铜矿对比,有利成矿的构造类型为"安第斯型",即扇形形态构造;与新疆周边国家和地区斑岩铜矿成矿带对比,新疆具有相类似的成矿地质条件,找矿远景很大,特别是西天山、西昆仑、木孜塔格、祁漫塔格、东准噶尔南部等地区,具有斑岩铜矿成矿的广阔前景,有希望找到新的大型-超大型铜矿床。

  12. 塔里木盆地北缘英岗地区铀成矿特征及找矿远景%Uranium Metallogenic Characteristics and Prospecting Prospective of Yinggang area of the Northern Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    李炎龙; 邬力生; 王国荣

    2016-01-01

    英岗地区位于塔里木盆地柯坪断隆,属塔里木北缘铀成矿带,区内含铀及富铀层众多,为铀矿化的形成提供了重要的物质来源。结合区域铀矿勘查成果,对区域地质背景、地质特征、铀成矿特征进行了详细分析,并划分了成矿远景区。研究结果表明:①英岗地区上石炭统康克林组具备铀资源找矿前景,初步确定其铀成矿类型为古层间氧化带型;②英岗地区上石炭统康克林组铀成矿可分为3个阶段,即晚石炭世铀初始富集阶段、早二叠世铀叠加富集阶段和新生代强烈构造改造阶段。上述分析成果对于该区今后铀矿找矿工作有一定的参考价值。%Yinggang area is located in Kalpin fault uplift of Tarim basin,it belongs to the uranium metallogenic belt of the northern Tarim basin,many uranium layers and rich uranium layers are distributed in Yinggang area,they area provide the important material resources of the formation of uranium minerali-zation.Based on the prospecting results of the uranium deposits in Yanggang area,the regional geological background,geological characteristics of the area,uranium metallogenic characteristics area analyzed,be-sides that the prospect areas are delineated.The study results show that:①the prospecting prospective of uranium deposit of upper carboniferous Kangkelin formation of Yinggang area is good,the uranium metal-logenic type of upper carboniferous Kangkelin formation is determined as inter -layer oxidation zone type;②the uranium metallogenic of upper carboniferous Kangkelin formation of Yinggang are can be di-vided into three stages,they are the initial enrichment stage of uranium in late carboniferous epoch,super-position enrichment stage of uranium in early permian epoch and strong tectonic reworking stage in ceno-zoic.The above study results can provide some reference for the uranium deposit prospecting work in Yinggang area.

  13. Post-collisional polycyclic plutonism from the Zagros hinterland: the Shaivar Dagh plutonic complex, Alborz belt, Iran

    NARCIS (Netherlands)

    Aghazadeh, Mehraj; Castro, Antonio; Badrzadeh, Zahra; Vogt, Katharina

    2011-01-01

    The petrological and geochronological study of the Cenozoic Shaivar Dagh composite intrusion in the Alborz Mountain belt (NW Iran) reveals important clues to decipher complex relations between magmatic and tectonic processes in the central sectors of the Tethyan (Alpine–Himalayan) orogenic belt. Thi

  14. ALPINE MAGMATIC-METALLOGENIC FORMATIONS OF THE NORTHWESTERN AND CENTRAL DINARIDES

    Directory of Open Access Journals (Sweden)

    Jakob Pamić

    1997-12-01

    Full Text Available In the paper are presented basic geological, petrologieca1, geochemi-cal and mineral deposit data for five main magmatic-metallogenic formations of the northwestern and central Dinarides: (lThe Permo Triassic rifting related andesite-diorite formations; (2 The Jurassic-Lower Cretaceous accretionary (ophiolite formations; (3 The Upper Cretaceous-Paleogene subduction related basalt-rhyohite formations; (4 The Paleogene collisional granite formations, and (5 The Oligo-cene-Neogene postsubduction andesite formations. All these magmatic-metallogenic formations originated in different geotectonic settings during the Alpine evolution of the Dinaridic parts of thc Tethys and the postorogenic evolution of the Paratethys and the Pannonian Basin, respectively.

  15. Lap belts and three-point belts.

    NARCIS (Netherlands)

    Kampen, L.T.B. van & Edelman, A.

    1975-01-01

    Results of the swov-accident investigation prove that if there are any differences in the effectiveness of lap belts and three-point belts, these are so small that they cannot form a basis for giving preference to one type over the other. Furthermore, in spite of the results of this investigation wh

  16. Metallogenesis of the Ertix gold belt, Xinjiang and its rela-tionship to Central Asia-type orogenesis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Ertix gold belt is located on the boundary of the Kalatongkearc and the Kelan back-arc basin of D-C1. Most scholars used to interpret the formation and distribution of the gold deposits in the Ertix tectonic belt in terms of the petrogenic and metallogenic models for active continental margins. However, enormous data of isotopic dating and geologic research show that the mineralization was obviously later than the oceanic subduction, whereas exactly simultaneous with the collisional orogenesis during C2-P, especially at the transition stage from collisional compression to extension. Based on study of metallogenic time, tectonic background, ore geology, ore fluid nature, ore material source, etc., we reveal that all the gold deposits possess the character of orogenic deposits formed in collisional orogenic system, and that their ore-forming materials mainly have derived from the stratigraphic terranes south to individual deposits. Accordingly, the theoretical tectonic model for collisional metallogenesis and petrogenesis is employed to explain the formation of the Ertix gold belt and to determine the gold exploration directions.

  17. 智利MARCIA铜矿地质特征及成矿机理%Geological characteristics and metallogenic mechanism of the Marcia copper deposit in Chile

    Institute of Scientific and Technical Information of China (English)

    李忠烈

    2012-01-01

    MARCIA铜矿位于智利海岸山脉成矿带,通过对矿区地层、地质特征、矿体特征与构造的关系等分析,对该矿区铜矿的形成机理进行了初步探讨,认为该矿区铜矿的形成与断裂关系密切,F2断裂是导矿和容矿断裂,该区找矿前景巨大.%The Marcia copper deposit is located in IOCG belt. Through analyzing the strata, geological characteristics, the orebody characteristics and tectonic features of the mining area, the metallogenic mechanism of the copper deposit was discussed. It has concluded that the formation of copper deposit in the mine are closely to the fault, the F2 fault is ore-transmitting and ore-containing fault and it has great prospecting potential in this area.

  18. 660铀矿田成矿地质特征及成矿预测%Geological characteristics and metallogenic prediction of No.660 uranium ore field

    Institute of Scientific and Technical Information of China (English)

    雷遥鸣

    2012-01-01

    火山岩型铀矿在我国铀矿资源中占有较大份额.660铀矿田是一个典型的火山岩型铀矿聚集区,对该区已发现的矿床、矿点以及成矿异常点(带)的地质特征进行研究分析,找出其矿化特征、矿体分布规律,总结出其控矿因素、成矿规律及成矿地质作用,并根据其成矿地质特征和找矿标志等,提出660铀矿田新一轮找矿预测区和方向.%Volcanic-type uranium deposits account for a large share in uranium ore resources of China. No. 660 uranium ore field is the metallogenie area of typical volcanic-type uranium deposits. The geo- logical features of discovered deposits, occurrences and metallogenic outliers (belt) in the region are studied in order to identify the mineralization characteristics and ore body distribution, and sum up its ore-controlling factors, regularities and geological roles of mineralization. According to its geological characteristics and mineralization abnormalities, a new target and direction of prospecting in No. 660 uranium ore field are pointed out.

  19. Evidence for volcanism in NW Ishtar Terra, Venus

    Science.gov (United States)

    Gaddis, L.; Greeley, Ronald

    Venera 15/16 radar data for an area in NW Ishtar Terra, Venus, show an area with moderate radar return and a smooth textured surface which embays low lying areas of the surrounding mountainous terrain. Although this unit may be an extension of the lava plains of Lakshmi Planum to the southeast, detailed study suggests a separate volcanic center in NW Ishtar Terra. Lakshmi Planum, on the Ishtar Terra highland, exhibits major volcanic and tectonic features. On the Venera radar image radar brightness is influenced by slope and roughness; radar-facing slopes (east-facing) and rough surfaces (approx. 8 cm average relief) are bright, while west-facing slopes and smooth surfaces are dark. A series of semi-circular features, apparently topographic depressions, do not conform in orientation to major structural trends in this region of NW Ishtar Terra. The large depression in NW Ishtar Terra is similar to the calderas of Colette and Sacajawea Paterae, as all three structures are large irregular depressions. NW Ishtar Terra appears to be the site of a volcanic center with a complex caldera structure, possibly more than one eruptive vent, and associated lobed flows at lower elevations. The morphologic similarity between this volcanic center and those of Colette and Sacajawea suggests that centralized eruptions have been the dominant form of volcanism in Ishtar. The location of this volcanic center at the intersection of two major compressional mountain belts and the large size of the calders (with an inferred large/deep magma source) support a crustal thickening/melting rather than a hot-spot origin for these magmas.

  20. Evolution of Mesozoic Volcanic Basins and Red Basins in the Gan-Hang Tectonic-Volcanic Metallogenic Belt

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper mainly proposes six major regional geological events in the active continental-margin mantle uplift zone and discusses the oscillation nature of the evolution of Mesozoic volcanic basins and red basins, origin of erosion in the late stage of red basins and mechanism of volcanism.

  1. Evolution of ore-forming fluids in the Sawayaerdun gold deposit in the Southwestern Chinese Tianshan metallogenic belt, Northwest China

    Science.gov (United States)

    Chen, Huayong; Chen, Yanjing; Baker, Michael J.

    2012-04-01

    The Sawayaerdun gold deposit was discovered in the early 1990s and is the largest orogenic-gold deposit in the Chinese Tianshan. Gold mineralization occurs in quartz veins, which are hosted in carbonaceous metasediments and controlled by faults and fractures. Three major hydrothermal events can be identified at Sawayaerdun: An early barren quartz vein stage, middle stage quartz veins with pyrite and gold mineralization and late carbonate (-quartz) veins. Fluid inclusion studies of quartz, pyrite and carbonate formed during the major hydrothermal stages show distinct changes in fluid, temperature, composition and redox conditions occurred during fluid evolution. Three types of fluid inclusions have been identified at Sawayaerdun: H2O + NaCl (L + V), H2O + NaCl + CO2 (L + V) and CO2 (L + V). Fluids trapped in early barren quartz have high temperatures (280-420 °C), low salinities (quartz formation, resulting in the generation of coexisting fluid inclusions with distinguishable vapor/liquid ratios and salinities. The compositional difference between fluids trapped in pyrite and quartz indicate fluid mixing may have occurred during the mineralization stage. The oxidized fluids, probably a mixture of meteoric water and fluids generated during water-host rock interaction, emerged into the ore-forming system to generate extensive metals precipitation. The fluid immiscibility and fluid mixing are most likely caused by pressure decrease during Late Paleozoic uplift and erosion in the Chinese Southern Tianshan area. Comparison of fluids between four major mineralization zones at Sawayaerdun indicate that zone II is similar to the most important zone IV and the order of similarity is probably zone II > XI > I, which could be applied to the future mineral exploration in this area.

  2. Better Buildings NW Ohio

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, Kevin [Toledo-Lucas County Port Authority, Toledo, OH (United States)

    2015-03-04

    Districts or ESIDs and what is nationally known as Property Assessed Clean Energy or PACE districts and PACE financing. The project methodology followed the identify, develop, implement, monitor and measure format. These districts began in Toledo and adjoining areas and are expanding to TLCPA’s 28 county financing agency geographic footprint. What began as the Toledo Ohio Advanced Energy Improvement Corporation is now doing business as the Northwest Ohio Advanced Energy Improvement District recognizing it expansion into creating and financing other districts in NW Ohio. The program has been sought out as an advisor by major communities and states in the process of developing similar legislation and programs and has become one of the largest most successful PACE energy improvement and financing districts in the US. The program and the energy district focused on transforming energy use, delivery, conservation and renewable energy as “options of first choice”. The significant energy savings paid for many of the improvements and created a financially viable program well beyond the grant period. The program has become a model within the State of Ohio and Nationally on how to implement and finance projects in broad energy districts including how to evolve and integrate several financing methodologies. It is a unique utilization of revolving loan funds and energy bond pooling with revenue backing primarily from energy improvement special assessments on commercial properties along with some power purchase agreement (PPA) and loan agreement revenue. The program has also incorporated Qualified Energy Conservation Bonds, State of Ohio Energy Loans (SEP), utility rebates, solar and renewable energy certificates, renewable tax incentives and grants, and owner funded equity as additional program leverage and funding. Other keys to this success have been a continual simplification and refinement of the application and documentation process to make funding available easily and

  3. STUDY ON TECTONIC FEATURE AND METALLOGENIC MECHANISM OF THE PENGSHAN Sn-Pb-Zn POLYMETALLIC OREFIELD,JIANGXI PROVINCE

    Institute of Scientific and Technical Information of China (English)

    LU Shudong; DU Yangsong; XIAO E; XU Chunwei

    2005-01-01

    The Pengshan Sn-Pb-Zn polymetallic orefield is located in the Jiujiang-Ruichang region, which is a segment of the middle-lower Yangtze River metallogenic belt. The Pengshan late Yanshanian buried pluton with granitic composition is a calc-alkaline pluton, intrusion of which is responsible for the formation of the Sn-Pb-Zn polymetallic deposit through providing thermodynamic condition and ore-forming material.The long-active basement rifts initially formed in the Jinning period and the domal structure with induced secondary order faults formed by emplacement of the pluton, such as ring-detachment fault,top-detachment fault and joint fissure, act as the passage-way for magma and ore-forming fluid and impounding structure for ore deposit. The magma to form the pluton with DI>90 is intensively differentiated. The variation of the ore-forming fluid in composition with falling in temperature caused by action of magmatic hydrothermal convection system combined with groundwater convection system attributes to mineralization of various types in the orefield. The mineralization process can be divided into six stages, i.e., greisenization, skarnization of early stage, fluorite-stanniferous silication stage, skarnization of advanced stage, quartz and cassiterite-sulfuration stage and carbonation stage. The mineral assemblages formed in different mineralization stages are different owing to temperature changing and may be overlapped in space. Malayaite is recognized from the mineral assemblage formed in the fluorite-stanniferous silication stage. The ores in the Pengshan Sn-Pb-Zn polymetallic deposit are spatially zoned with variation from As-Sn mineral assemblage of high temperature in the inner zone through Sn-Pb and Pb-Zn-Ag mineral assemblage of middle temperature in the middle zone to fluorite mineral assemblage of low temperature in the outer zone.The exchanging of Sn,Mg and Fe between biotite and hydrothermal fluid resulted from variation of physicochemical condition

  4. Geology of the Naturita NW quadrangle, Colorado

    Science.gov (United States)

    Cater, Fred W.; Vogel, J.D.

    1953-01-01

    The Naturita NW quadrangle is one of eighteen 7 1/2-minute quadrangles covering the principal carnotite-producing area of southwestern Colorado. The geology of these quadrangles were mapped by the U.S. Geological Survey on behalf of the U.S. Atomic Energy Commission as part of a comprehensive study of carnotite deposits. The rocks exposed in the eighteen quadrangles consist of crystalline rocks of pre-Cambrian age and sedimentary rocks that range in age from late Paleozoic to Quaternary. Over much of the area the sedimentary rocks are flat lying, but in places the rocks are disrupted by high-angle faults, and northwest-trending folds. Conspicuous among the folds are large anticlines having cores of intrusive salt and gypsum. Most of the carnotite deposits are confined to the Salt Wash sandstone member of the Jurassic Morrison formation. Within this sandstone, most of the deposits are spottily distributed through an arcuate zone known as the "Uravan Mineral Belt". Individual deposits range in size from irregular masses containing only a few tons of ore to large, tabular masses containing many thousands of tons. The ore consists largely of sandstone selectively impregnated and in part replaced by uranium and vanadium minerals. Most of the deposits appear ro be related to certain sedimentary structures in sandstones of favorable composition.

  5. The giant South China Mesozoic low-temperature metallogenic domain: Reviews and a new geodynamic model

    Science.gov (United States)

    Hu, Ruizhong; Fu, Shanling; Huang, Yong; Zhou, Mei-Fu; Fu, Shaohong; Zhao, Chenghai; Wang, Yuejun; Bi, Xianwu; Xiao, Jiafei

    2017-04-01

    The South China Craton was formed by amalgamation of the Yangtze and Cathaysia Blocks during the Neoproterozoic. During the Mesozoic, voluminous granitic plutons and associated W-Sn polymetallic deposits were formed in the Cathaysia Block. The giant South China low-temperature metallogenic domain (LTMD) includes an area of ∼500,000 km2 in the Yangtze Block and is composed of the Chuan-Dian-Qian Pb-Zn, Youjiang Au-As-Sb-Hg and Xiangzhong Sb-Au metallogenic provinces. The Chuan-Dian-Qian Pb-Zn province contains numerous MVT Pb-Zn deposits, whereas the other two provinces are characterized by Carlin-type Au deposits and vein-type Sb, Hg and As deposits. These epigenetic deposits, which formed under low temperature conditions (∼100-250 °C), are typically hosted in sedimentary rocks and are locally controlled by faults and fractures. The deposits formed dominantly at 200-230 Ma and 130-160 Ma, corresponding to Indosinian (Triassic) and Yanshanian (Jurassic to Cretaceous) orogenies, respectively. Indosinian mineralization is recognized in all three provinces, but Yanshanian mineralization occurred only in the Youjiang and Xiangzhong provinces. The Indosinian orogeny, which involved collision of the Indochina Block with the South China Craton, resulted in circulation of basinal brines that leached ore-forming elements from adjacent sedimentary strata to form the Chuan-Dian-Qian Pb-Zn province. Deep-seated granitic magmas generated during this orogeny caused extensive circulation of meteoric water that mobilized ore-forming elements from the sedimentary strata to form the Carlin-type Au deposits in the Youjiang province, and the Sb-Au deposits in the Xiangzhong province. The Indosinian orogeny was the key factor in establishing the metallogenic framework of the LTMD. It produced widespread mineralization in the three metallogenic provinces, each of which has unique features reflecting differences in the nature and composition of the basement rocks. The Yanshanian

  6. 巴基斯坦重要金属成矿带遥感战略选区研究%A study on strategic area selection of remote sensing in important metallization belts of Pakistan

    Institute of Scientific and Technical Information of China (English)

    刘碧虹; 张云峰; 张建国; 李冬月

    2014-01-01

    Pakistan locates in the eastern part of Tethys metallogenic domain according to global metallogenic planning,and chinese Bangong lake-Nujiang,Gangdise Cu polymetallic ore belt occurs in the same metallo-genic belt which has abundant mineral resources.By using multi-platform satellite remote sensing data,this research takes advantage of remote sensing technology and carries out remote sensing geological interpreta-tion,alteration information extraction and comprehensive analysis in important metallogenic belts of Paki-stan.Seven strategic areas are selected,and four prospecting favorable locations are blocked.It provides technical support and basic geological mineral information for chinese enterprises to carry out overseas miner-al resources exploration in"going-out" strategy.%巴基斯坦位于全球成矿区划的特提斯成矿域东段,与我国的班公湖-怒江、冈底斯铜多金属矿带同处一个成矿带上,矿产资源丰富。本次研究充分利用遥感技术优势,采用多平台卫星遥感数据,对巴基斯坦重要金属成矿带开展遥感地质解译、蚀变信息提取及综合分析,优选出了7个战略选区,圈定了可供优先开展地质工作的4处找矿有利地段,为我国企业“走出去”开展境外矿产资源勘查提供技术支撑和基础地质矿产信息。

  7. Gondwana to Pangea: a detrital zircons tale from NW Iberia

    Science.gov (United States)

    Pastor-Galán, Daniel; Gutiérrez-Alonso, Gabriel; Brendan Murphy, J.; Fernández-Suárez, Javier; Hofmann, Mandy; Linnemann, Ulf

    2013-04-01

    The Cantabrian Zone of NW Iberia preserves a voluminous, almost continuous, sedimentary sequence that ranges from Neoproterozoic to Early Permian in age. Its tectonic setting is controversial and recent hypotheses include (i) passive margin deposition along the northern margin of Gondwana or (ii) an active continental margin or (iii) a drifting ribbon continent. In this paper we present detrital zircon U-Pb laser ablation age data from 13 samples from the Cantabrian Zone sequence ranging from Early Silurian to Early Permian in depositional age, which, together with previously published detrital zircon ages from Ediacaran-Ordovician strata, allow a comprehensive analysis of changing provenance through time. Laser ablation U-Pb geochronological analysis of detrital zircons in thirteen samples of the Cantabrian Zone of the NW Iberian Variscan belt reveal that this portion of Iberia was part of the northern passive-margin of Gondwana from the Ordovician to Late Devonian, until the onset of collision between Gondwana and Laurentia. Zircon populations in these samples show important similarities with zircons found in coeval detrital rocks from central North Africa. Additionally, the populations found in NW Iberia are coherent with a Saharan source. We suggest that NW Iberia was situated from Ordovician to Late Devonian along the Gondwana northern passive margin close to the paleoposition of central North Africa and Saharan craton. Additionally, the Carboniferous-Permian samples studied record the provenance changes produced during the Variscan collision and basement exhumation, the Cantabrian orocline formation and the subsequent detachment of the lithospheric mantle. The provenance changes reflect major topographic variations due to the afore mentioned processes during Late Devonian to Early Permian times. Detrital zircon studies are a useful tool that can complement regional syntheses in deducing paleogeographic locations, the occurrence of major tectonic events such

  8. Metallogenic Systems on the Paleocontinental Margin of the North China Craton

    Institute of Scientific and Technical Information of China (English)

    ZHAI Yusheng; DENG Jun; TANG Zhongli; XIAO Rongge; SONG Honglin; PENG Runmin; SUN Zhongshi; WANG Jianping

    2004-01-01

    The North China Craton (NCC) is one of the largest blocks composing the continent. Different types of continental margins well developed around the NCC, along with lots of metallogenic systems of different metals and different times. Based on the study on the structural evolution of the NCC, the authors made a new division of tectonic units of the NCC. Through an analysis of the data of 1:25000 geochemical survey on stream sediments, regional geochemical features of main ore-forming elements including Au, Ag, Cu, Pb, Zn, W, Ni, Co and Mo of the NCC are discussed in the paper. Then different metallogenic systems and their forming processes and geodynamics are discussed in detail. At last, temporal and spatial distribution regularities are summarized and ten favorable ore-control factors on the paleocontinental margins are put forward, including (1) abundance of ore sources; (2) rendezvous of ore-forming fluids; (3) high thermo-dynamic anomaly; (4) remarkable Earth crust-mantle interaction; (5) cluster of macroscopic structures and their long activities; (6) diversity of ore-forming environments; (7) long geohistory; (8) multiforms of critical transitional ore-forming mechanisms; (9) multi-staged and superimposed ore-formation; and (10) suitable preservation condition.

  9. Origin and Superposition Metallogenic Model of the Sandstone-type Uranium Deposit in the Northeastern Ordos Basin, China

    Institute of Scientific and Technical Information of China (English)

    LI Ziying; CHEN Anping; FANG Xiheng; OU Guangxi; XIA Yuliang; SUN Ye

    2008-01-01

    This paper deals with the metallogenic model of the sandstone type uranium deposit in thenortheastern Ordos Basin from aspects of uranium source, migration and deposition. A superpositionmetallogenie model has been established due to complex uranium mineralization processes withsuperposition of oil-gas reduction and thermal reformation.

  10. New Early Paleozoic Paleomagnetic Poles From NW Argentina: a Reappraisal of Tectonic Models

    Science.gov (United States)

    Spagnuolo, C. M.; Rapalini, A. E.; Astini, R. A.

    2007-05-01

    A paleomagnetic study carried out on Early Ordovician volcanic units in the Famatina Ranges of NW Argentina yielded a pre-tectonic paleomagnetic pole at 32.7°S, 4.3°E, (5.6°/ 8.6°, N=14 sites) that is consistent with four previous Early Ordovician poles from the Famatina - Eastern Puna Eruptive Belt of NW Argentina. However, these five poles are rotated around 50° clockwise respect to the coeval reference pole of Gondwana. Our new results seem to confirm previous models of this belt as a paraauthocthonous rotated terrane on the southwestern margin of Gondwana. However, a recent paleomagnetic pole from the Late Cambrian Mesón Group, at the Eastern Cordillera of NW Argentina, corresponding to the Gondwana foreland (4.5°S, 359.0°E, dp=5.5°, dm=8.8°, n=26 samples) and preliminary paleopoles obtained from the same unit and the latest Cambrian - Early Ordovician Santa Victoria Group at other three localities in the same region, also indicate an anomalous pole position rotated some 40° clockwise respect to the reference pole for Gondwana. These results suggest that the postulated model of a rotated terrane for the Famatina-Eastern Puna belt must be reconsidered. Different alternative scenarios including the possibility of an Early Paleozoic displacement of the whole basement of the Eastern Sierras Pampeanas of Argentina ("Pampia") will be explored.

  11. Seat belt restraint system

    Science.gov (United States)

    Garavaglia, A.; Matsuhiro, D.

    1972-01-01

    Shoulder-harness and lap-belt restraint system was designed to be worn by individuals of widely different sizes and to permit normal body motion except under sudden deceleration. System is divided into two basic assemblies, lap belt and torso or shoulder harness. Inertia-activated reels immediately lock when seat experiences sudden deceleration.

  12. The"Three-in-One"Deposit Type and Metallogenic Mechanism of Niujiaowo Tungsten Polymetallic Mine in Chongyi County Jiangxi Province%江西崇义牛角窝钨多金属“三位一体”矿床类型及成矿机制探讨

    Institute of Scientific and Technical Information of China (English)

    陈小勇; 谢有炜; 丁明; 游磊; 邬思涛; 肖汉冲

    2013-01-01

    崇义牛角窝钨多金属矿床位于南岭东部钨锡多金属成矿带崇义-大余-上犹矿集区内。矿区产出破碎蚀变岩-石英脉复合型、石英细脉带型、云英岩型三种钨矿床类型,同受燕山期成矿花岗岩体控制,且三种矿床类型具有一定的空间配置关系,相互间具有密切的成生联系,从而形成“三位一体”模式。对矿区“三位一体”模式的研究有助于深刻认识钨多金属矿床的组合产出规律,进行钨矿床地质特征及成矿机制探讨,指导矿区勘查和区域找矿。%Niujiaowo tungsten polymetallic deposit is located in the Chong-Yu-You ore concentration area of eastern Nanling tungsten-tin polymetallic metallogenic belt. The tungsten polymetallic district occurs in three deposit types including fractured altered rock-quartz vein type, quartz veinlets zone type and greisen type. These types are demonstrated in the form of"three-in-one", are all controlled by the Yanshan metallogenic granite bodies. This paper studies the geological characteristics and metallogenic mechanism by conducting comprehensive analysis of the deposit.

  13. Radiation Belt Dynamics

    Science.gov (United States)

    2015-12-27

    Wygant, J. R., et al., “The Electric Field and Waves Instruments on the Radiation Belt Storm Probes Mission,” Space Sci. Rev., 179, 2013, pp. 183–220, doi...A. N., Li, X., Kanekal, S. G., Hudson, M. K., and Kress, B. T., “Observations of the Inner Radiation Belt: CRAND and Trapped Solar Protons,” J...1215–1228, doi:10.1002/2014JA020777. [27] Selesnick, R. S., “ Measurement of Inner Radiation Belt Electrons with Kinetic Energy Above 1 MeV,” J

  14. KEY ROLE OF METALLOGENIC THEORY OF POLYGENETIC COMPOUND ORE DEPOSITS IN LOCATION PREDICTION OF HIDDEN ORE DEPOSITS IN DIWA REGIONS

    Institute of Scientific and Technical Information of China (English)

    PENG; Sheng-lin; LIU; Liang-ming; LAI; Jian-qing

    2001-01-01

    The metallogenic theory of polygenetic compound ore deposit is the Important basis for location prediction of hidden ore deposits in diwa regions.It can play an important role in each step of prediction research,targeting procedure,acquiring information and integrating information.In this paper,the authors discusses how to construct geological concept by using of the metallogenic theory of polygenetic ore deposits for predicting targeting area,to arrange investigation and detection for getting enough useful information,and to analyze and integrate information for reaching a trustful prediction conclusion.According to these strategies,we conduct a successful prediction of location of hidden ore bodies in the outer of the Fenghuangshan copper mine,a principal producing mine in Tongling Cu-Au district.

  15. Mineral Chemistry and Boron Isotopic Composition of Tourmaline from the Devonian Metallogenic District of Shanyang-Zhashui,Eastern Qinling

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    Tourmaline is widespread in the host strata of strata-bound base metal sulphide deposits in the Devonian metallogenic deistrict around Shanyang-Zhashui in eastern Qinling,As a member of the schorl-dravite series,the tourmaline is characterized by Mg>Fe and Na>Ca,showing apparent chemical zonation which records the geochemistry during its formation and subsequent regional metamorphism and hydrothermal overprint.The close similarity in chemical and isotopic constitutions between the tourmaline of the main metallogenic epoch in this district [FeO/(FeO_MgO)=0.34-0.39and δ11B=-7.6‰--8.8‰] and those related to massive sulphide deposits typical of submarine(exhalative)hydrothermal sedimentation may add further support to a similar mechanism of mineralization for strata-bound depostis in the district.

  16. Dynamic characteristics of conveyor belts

    Institute of Scientific and Technical Information of China (English)

    HOU You-fu; MENG Qing-rui

    2008-01-01

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

  17. Metallogenic Series Related to Permian Mafic Complex in North Xinjiang: Post-collisional Stage or Mantle Plume Result?

    Institute of Scientific and Technical Information of China (English)

    WANG Yuwang; WANG Jingbin; WANG Lijuan; LONG Lingli

    2008-01-01

    There are four deposit types related to a Permian mafic complex in northern Xinjiang, i.e.,copper-nickel sulfide deposit, vanadic titanomagnetite deposit, magnetite (-cobalt) deposit and Cu-Ni-VTiFe composite deposit. The deposits are distributed spanning tectonic units with dose andconsecutive metallogenic ages. A transitional deposit type can occur among the end-member deposits.Trace elements of host rocks show that they can derive from similar source area. Hence, theyconstitute a particular metallogenic series related to a mafic-ultramafic complex that is also a symbolseries of the post-collisional stage of the Central Asia Metallogenic Province (CAMP). Themetallogenic ages of the series are between 260 Ma and 300 Ma throughout the Permian. Unlikemineralization from a mantle plume, the metallogenic period of this series spans at least 40 Ma.Compared with related deposits of the Emeishan mantle plume, the North Xinjiang series has asimilar ore-forming element assemblage but has preferably developed Cu-Ni sulfide deposits ratherthan vanadic titanomagnetite deposits. In concomitance with this series, North Xinjiang area hasdeveloped a set of syntectonic Au-Cu-Mo metailogenic series related to a felsic volcanic-intrusivecomplex, which might indicate that there is no direct relationship with mantle plume activity. Fromearly to late, i.e., the sequence of copper-nickel sulfide to magnetite (-cobalt) to vanadictitanomagnetite deposit, the host rock series evolves from mafic-ultramafic and tholeiite series tomafic and alkalic series, the ∑REE content tends to increase with increasing of REE fractionation, andsome of the trace elements (particularly LIL) also show an increasing tendency. The aboveevolutionary regularity possibly reflects a course where the magma source deepens and thermalinterface moves down, energy gradually exhausts, and neo-continentai crust forming in the post-collision stage tends to stabilize.

  18. DESIGN TRENDS IN TIMING BELTS

    OpenAIRE

    Grzegorz DOMEK

    2014-01-01

    Paper presents the state of the art gear with timing belts. Areas of use pose new challenges for designers gear. It has materials and technologies used in the production. Has been developed algorithm of design timing belts to new applications

  19. The origin of the Avram Iancu U-Ni-Co-Bi-As mineralization, Băiţa (Bihor) metallogenic district, Bihor Mts., Romania

    Science.gov (United States)

    Zajzon, Norbert; Szentpéteri, Krisztián; Szakáll, Sándor; Kristály, Ferenc

    2015-10-01

    The Băiţa metallogenic district in the Bihor Mountains is a historically important mining area in Romania. Uranium mining took place between 1952 and 1998 from various deposits, but very little is known about the geology and mineralogy of these deposits. In this paper, we describe geology and mineralogy of uranium mineralization of the Avram Iancu uranium mine from waste dump samples collected before complete remediation of the site. Texturally and mineralogically complex assemblages of nickeline, cobaltite-gersdorffite solid solution, native Bi, Bi-sulfosalts, molybdenite, and pyrite-chalcopyrite-sphalerite occur with uraninite, "pitchblende," and brannerite in most of the ore samples. The association of nickel, cobalt, and arsenic with uranium is reminiscent of five-element association of vein type U-Ni-Co-Bi-As deposits; however, the Avram Iancu ores appear to be more replacement-type stratiform/stratabound. Avram Iancu ore samples contain multistage complex, skarn, uranium sulfide, arsenide assemblages that can be interpreted to have been formed in the retrograde cooling stages of the skarn hydrothermal system. This mineralizing system may have built-up along Upper Cretaceous-Paleogene "Banatite" intrusions of diorite-to-granite composition. The intrusions crosscut the underlying uraniferous Permian formations in the stacked NW-verging Biharia Nappe System. The mineralization forms stacked, multilayer replacement horizons, along carbonate-rich lithologies within the metavolcanic (tuffaceous) Muncel Series. Mineral paragenesis and some mineral chemistry suggest moderate-to-high uranium sulfide stage along stratigraphically controlled replacement zones and minor veins. Uranium minerals formed abundantly in this early stage and include botryoidal, sooty and euhedral uraninite, brannerite, and coffinite. Later and/or lower-temperature mineral assemblages include heterogeneous, complexly zoned arsenide-sulfarsenide solid solutions associated with minute but

  20. Radiation belts of jupiter.

    Science.gov (United States)

    Stansberry, K G; White, R S

    1973-12-07

    Predictions of Jupiter's electron and proton radiation belts are based mainly on decimeter observations of 1966 and 1968. Extensive calculations modeling radial diffusion of particles inward from the solar wind and electron synchrotron radiation are used to relate the predictions and observations.

  1. Global trends in the evolution of metallogenic processes as a reflection of supercontinent cyclicity

    Science.gov (United States)

    Tkachev, A. V.; Rundqvist, D. V.

    2016-07-01

    The worldwide distribution of large and superlarge mineral deposits (LSLDs) on a geological time scale is analyzed. It has been established that their formation from Eoarchean to Cenozoic was nonuniform in time. The maxima and minima of ore generation intensity correlate well with global cyclical processes, eventually resulting in the assembly and breakup of supercontinents. The periods of supercontinent amalgamation are characterized by the highest rate of continental crust growth due to the contribution of juvenile sources, a maximum of orogenic activity, and the most intense deposit formation. Periods close to betweencycle boundaries are distinguished by a low intensity of both endogenic and ore-forming processes. As follows from the available data, the number of known LSLDs slightly decreases from the Kenoran to Columbian cycle, significantly decreases in the next Rodinian cycle, which, in turn, is followed by abrupt growth in the Pangaean and Amasian cycles, especially as concerns LSLDs of the granitoid-related class. The intensification of metallogenic activity correlates with a commensurable increase in orogenic activity of the Earth's crust probably caused by continental crust expansion, an increase in the number of sialic blocks participating in the formation of accretionary and collisional orogens, and acceleration of lithospheric plate motion. Some trends are also described for other LSLD classes (basic-alkaline, volcanic-hosted massive sulfide, sedimentary, epigenetic sediment-hosted), caused to a certain extent by supercontinent cycles and their evolutionary variations.

  2. Copper-Polymetal Metallogenic Series and Prospecting Perspective of Eastern Section of Gangdise

    Institute of Scientific and Technical Information of China (English)

    Zheng Youye; Xue Yingxi; Gao Shunbao

    2003-01-01

    Geological, geophysical, geochemical and remote sensing comprehensive studies show that big ore-prospecting potentiality is contained in the eastern section of the Gangdise Mountains, Tibet.There are various mineralization types with dominant types of porphyry and exhalation. According to their relations with tectonic evolution, they are divided into four kinds of metallogenic series as follows:magmatic type (Cr, Pt, Cu, Ni) and exhalation type (Cu, Pb, Zn, Ag) ore deposit series related to Neo-Tethys oceanic crust subduction action (125-96 Ma); epithermal type (Au, Ag, Pb, Zn, Sb), altered fractured rock type (Cu, Mo) and skarn rock type (Cu) ore deposit series related to arc-continental collision; porphyry type (Cu, Mo), cryptoexplosion breccia type (Cu, Au, Pb, Zn), shear zone type (Au, Ag, Sb) and skarn rock type (Cu, Fe) ore deposit series with relation to post-orogenic extensional strike-slip. From subductive complex to the north, zoning appears to be crystallization differentiation type (segregation type)-shear zone type (altered rock type)-skarn rock type, epithermal type-porphyry type-porphyry type and exhalation type-exhalation type-hydrothermal filling-replacement type.The ore deposit is characterized by multi-places from the same source, parity and multi-stage, hypabyssal rock from the deep source and poly genetic compound as a whole.

  3. Arctic-Asian Mobile Belt - Global Structure in the North, Central, and East Asia

    Science.gov (United States)

    Shokalsky, Sergey; Petrov, Oleg; Pospelov, Igor; Kashubin, Sergey; Sobolev, Nikolay; Petrov, Evgeny

    2014-05-01

    Over the last decade under the international project of five countries, the geological surveys of Russia, China, Kazakhstan, Mongolia, and the Republic of Korea, with the participation of national academies of sciences in these countries compiled a set of digital maps at 1:2.5 M scale. It includes geological, tectonic, metallogenic maps and map of energy resources with databases for North, Central, and East Asia, area of more than 30 million km2. Map compilation was supervised by the Subcommission for Northern Eurasia and Subcommission for Tectonic Maps of the Commission for the Geological Map of the World under the auspices of UNESCO (CGMW). The set of maps was displayed at the 33rd IGC (Oslo, 2008) and 34th IGC (Brisbane, 2012). One of the largest accretion collages of orogenic belts of different ages on the planet (from the Neoproterozoic to Early Mesozoic) is clearly shown in the tectonic map compiled under the joint project. Extended polychronous mobile belt is bounded in the west by the East European Craton, in the east, by the Siberian Craton, in the south, by a chain of Gondwana cratonic blocks - North China, Tarim, Tajik. In the north it can be traced as a broad band within the Circumpolar Region, where it is limited by the North American Craton. The central part of the accretionary belt is hidden under the Meso-Cenozoic sediments of Western Siberia. Analysis of vast geological material shows that the Arctic-Asian mobile belt was formed on place of an extensive paleo-ocean, which closed with a successive rejuvenation of suture ophiolite zones from the marginal to axial zone and along strike to the north and east of the South Siberian segment towards Paleopacific. Arctic-Asian mobile belt is characterized by a complex combination of accretionary and riftogenic tectonic-magmatic processes. At its early stages, accretionary tectonics with a wide development of volcanic belts dominated; at the late ones (in the Late Paleozoic, Mesozoic, and Cenozoic

  4. The empty primordial asteroid belt.

    Science.gov (United States)

    Raymond, Sean N; Izidoro, Andre

    2017-09-01

    The asteroid belt contains less than a thousandth of Earth's mass and is radially segregated, with S-types dominating the inner belt and C-types the outer belt. It is generally assumed that the belt formed with far more mass and was later strongly depleted. We show that the present-day asteroid belt is consistent with having formed empty, without any planetesimals between Mars and Jupiter's present-day orbits. This is consistent with models in which drifting dust is concentrated into an isolated annulus of terrestrial planetesimals. Gravitational scattering during terrestrial planet formation causes radial spreading, transporting planetesimals from inside 1 to 1.5 astronomical units out to the belt. Several times the total current mass in S-types is implanted, with a preference for the inner main belt. C-types are implanted from the outside, as the giant planets' gas accretion destabilizes nearby planetesimals and injects a fraction into the asteroid belt, preferentially in the outer main belt. These implantation mechanisms are simple by-products of terrestrial and giant planet formation. The asteroid belt may thus represent a repository for planetary leftovers that accreted across the solar system but not in the belt itself.

  5. Tertiary evolution of the Shimanto belt (Japan): A large-scale collision in Early Miocene

    Science.gov (United States)

    Raimbourg, Hugues; Famin, Vincent; Palazzin, Giulia; Yamaguchi, Asuka; Augier, Romain

    2017-07-01

    To decipher the Miocene evolution of the Shimanto belt of southwestern Japan, structural and paleothermal studies were carried out in the western area of Shikoku Island. All units constituting the belt, both in its Cretaceous and Tertiary domains, are in average strongly dipping to the NW or SE, while shortening directions deduced from fault kinematics are consistently orientated NNW-SSE. Peak paleotemperatures estimated with Raman spectra of organic matter increase strongly across the southern, Tertiary portion of the belt, in tandem with the development of a steeply dipping metamorphic cleavage. Near the southern tip of Ashizuri Peninsula, the unconformity between accreted strata and fore-arc basin, present along the whole belt, corresponds to a large paleotemperature gap, supporting the occurrence of a major collision in Early Miocene. This tectonic event occurred before the magmatic event that affected the whole belt at 15 Ma. The associated shortening was accommodated in two opposite modes, either localized on regional-scale faults such as the Nobeoka Tectonic Line in Kyushu or distributed through the whole belt as in Shikoku. The reappraisal of this collision leads to reinterpret large-scale seismic refraction profiles of the margins, where the unit underlying the modern accretionary prism is now attributed to an older package of deformed and accreted sedimentary units belonging to the Shimanto belt. When integrated into reconstructions of Philippine Sea Plate motion, the collision corresponds to the oblique collision of a paleo Izu-Bonin-Mariana Arc with Japan in Early Miocene.

  6. Kuiper Belt Occultation Predictions

    CERN Document Server

    Fraser, Wesley C; Trujillo, Chad; Stephens, Andrew W; Kavelaars, JJ; Brown, Michael E; Bianco, Federica B; Boyle, Richard P; Brucker, Melissa J; Hetherington, Nathan; Joner, Michael; Keel, William C; Langill, Phil P; Lister, Tim; McMillan, Russet J; Young, Leslie

    2013-01-01

    Here we present observations of 7 large Kuiper Belt Objects. From these observations, we extract a point source catalog with $\\sim0.01"$ precision, and astrometry of our target Kuiper Belt Objects with $0.04-0.08"$ precision within that catalog. We have developed a new technique to predict the future occurrence of stellar occultations by Kuiper Belt Objects. The technique makes use of a maximum likelihood approach which determines the best-fit adjustment to cataloged orbital elements of an object. Using simulations of a theoretical object, we discuss the merits and weaknesses of this technique compared to the commonly adopted ephemeris offset approach. We demonstrate that both methods suffer from separate weaknesses, and thus, together provide a fair assessment of the true uncertainty in a particular prediction. We present occultation predictions made by both methods for the 7 tracked objects, with dates as late as 2015. Finally, we discuss observations of three separate close passages of Quaoar to field star...

  7. The Regularity of Gold Enrichment and Its Implications to Metallogenic Tectonics in Shuangwang Gold Deposit,Shaanxi Province%陕西双王金矿床矿化富集规律对成矿构造的指示意义

    Institute of Scientific and Technical Information of China (English)

    宫勇军; 姚书振; 谭满堂; 曹瑞荣; 程建军

    2016-01-01

    rightward contortion in the early stage,which formed the rudiment of breccia belt.In the intermediate stage,earthquake and associated hydraulic fracturing,which were induced along with the fault movement,produced the main breccia bodies together with fractures and fissures;in the gold mineragenetic process,the brecciation trailed off,while the fractures and fissures developed continuously,and they played important roles of the main pathway as well as advantaged ore-forming space for metallogenic fluid,so the gold enrichment revealed planar distri-bution,and the change of the fractures and fissures occurrence was the basic factor that resulted in Au precipitation.In the late stage,the extension changed to east-west,and the mafic dyke swarms intruded in the setting,which were altered by metallo-genic fluid.

  8. Tectonic configuration of the Apuseni-Banat—Timok-Srednogorie belt, Balkans-South Carpathians, constrained by high precision R e-O s molybdenite ages

    Science.gov (United States)

    Zimmerman, Aaron; Stein, Holly J.; Hannah, Judith L.; Koželj, Dejan; Bogdanov, Kamen; Berza, Tudor

    2008-01-01

    The Apuseni-Banat-Timok-Srednogorie magmatic-metallogenic belt (ABTS belt), forms a substantial metallogenic province in the Balkan-South Carpathian system in southeastern Europe. The belt hosts porphyry, skarn, and epithermal deposits mined since pre-Roman times. Generally, the deposits, prospects, and occurrences within the belt are linked to magmatic centers of calc-alkaline affinity. Fifty-one rhenium-osmium (Re-Os) ages and Re concentration data for molybdenites define systematic geochronologic trends and constrain the geochemical-metallogenic evolution of the belt in space and time. From these data and additional existing geologic-geochemical data, a general tectonic history for the belt is proposed. Mineralization ages in Apuseni-Banat, Timok, and Panagyurishte (the central district of the larger E-W Srednogorie Zone) range from 72-83, 81-88, and 87-92 Ma, respectively, and clearly document increasing age from the northwestern districts to the southeastern districts. Further, Re-Os ages suggest rapidly migrating pulses of Late Cretaceous magmatic-hydrothermal activity with construction of deposits in ~1 m.y., districts in ~10 m.y., and the entire 1,500 km belt in ~20 m.y. Ages in both Timok and Panagyurishte show systematic younging, while deposit ages in Banat and Apuseni are less systematic reflecting a restricted evolution of the tectonic system. Systematic differences are also observed for molybdenite Re concentrations on the belt scale. Re concentrations generally range from hundreds to thousands of parts per million, typical of subduction-related Cu-Au-Mo-(PGE) porphyry systems associated with the generation of juvenile crust. The geochronologic and geochemical trends are compatible with proposed steepening of subducting oceanic slab and relaxation of upper continental plate compression. Resulting influx of sub-continental mantle lithosphere (SCML) and asthenosphere provide a fertile metal source and heat, while the subducting slab contributes connate

  9. Lap belt injuries in children.

    LENUS (Irish Health Repository)

    McGrath, N

    2010-07-01

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

  10. Geology and origin of Ag-Pb-Zn deposits occurring in the Ulaan-Jiawula metallogenic province, northeast Asia

    Science.gov (United States)

    Nie, Feng-jun; Li, Qiang-feng; Liu, Chun-hua; Ding, Cheng-wu

    2015-01-01

    Located at the conjunction area of China, Mongolia and Russia in NE Asia, the Ulaan-Jiawula (also referred as UJ) region, with an area of 400,000 km2, is one of the most important Ag-Pb-Zn, U, Sn, W, Nb-Ta, and Au metallogenic provinces in Asia. At present, 2126 deposits and showings including 500 Ag-Pb-Zn deposits have been discovered, explored and mined since the late 1960s. These Ag-Pb-Zn occurrences can be subdivided into three types according to their geological setting, texture, alteration and mineral assemblages: (1) low sulfidation epithermal Ag-Pb-Zn deposits; (2) intermediate sulfidation epithermal Ag-Pb-Zn deposits; (3) mixed-type Ag-Pb-Zn deposit consisting of vein-like and tabular ore bodies. The Eren Tologoi and Tsagenbulagen deposits are representative of low-sulphidation type Ag-Pb-Zn mineralization in the UJ region, and are associated with intensive adularization and sericitization. Ore occurs as mineralized quartz veins, veinlet groups and altered-fracture zones within Mesozoic alkaline and high-K calc-alkaline volcanic rocks, Ore mineralogy includes native silver, electrum, pyrite, galena, sphalerite, arsenopyrite, pyrargyrite and chalcopyrite. The Tsav and Jiawula deposits are typical of intermediate sulfidation Ag-Pb-Zn mineralization. The δ34S value of sulfide (pyrite and galena) separates from groups 1 and 2 varies from 1.5‰ to 3.5‰ and 2.0‰ to 4.5‰, respectively. The δ34S values of the Mesozoic volcanic host rocks for groups 1 and 2 deposits also show the positive δ34S values of 1.5-4.8‰, while the δ34S value of pyrite separate from the pre-Jurassic schist range from -6‰ to -8‰ which are much lower than Mesozoic volcanic host rocks and their associated ore deposits. There is no difference between the δ34S value of sulfide (pyrite and galena) separates from vein-like ore bodies of the group 3 deposits and their wall rocks, having δ34S value of 1.0-5.0‰ and 1.2-4.5‰ which are similar to that of groups 1 and 2 deposits

  11. SLH Timing Belt Powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Abe

    2014-04-09

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

  12. NW CSC annual report fiscal year 2013

    Science.gov (United States)

    Bisbal, Gustavo A.

    2013-01-01

    The Northwest Climate Science Center (NW CSC) was established in 2010 as one of eight regional Climate Science Centers created by the Department of the Interior (DOI). The NW CSC encompasses Washing-ton, Oregon, Idaho, and western Montana and has overlapping boundaries with three Landscape Conservation Cooperatives (LCCs): the Great Northern, the Great Basin, and the North Pacific. With guidance from its Executive Stakeholder Advisory Committee (ESAC), the NW CSC and its partner LCCs are addressing the highest priority regional climate science needs of Northwest natural and cultural resource managers. Climate Science Centers tap into the scientific expertise of both the U.S. Geological Survey (USGS) and academic institutions. The NW CSC is supported by an academic consortium with the capacity to generate climate science and tools in a coordinated fashion, serving stakeholders across the Northwest region. This consortium is primarily represented by Oregon State University (OSU), the University of Id-ho (UI), and the University of Washington (UW). The academic consortium and USGS provide capabilities in climate science, ecology, impacts and vulnerability assessment, modeling, adaptation planning, and advanced information technology, all necessary to address and respond to climate change in the Northwest. University members also recruit and train graduate students and early-career scientists. This Annual Report summarizes progress for the goals set out in the NW CSC Strategic Plan for 2012-2015 (http://www.doi.gov/csc/northwest/upload/Northwest-CSC-Strategic-Plan.cfm) and the NW CSC Work-plan for Fiscal Year (FY) 2013 (October 1, 2012 through September 30, 2013). The report follows the structure of the Strategic Plan, which describes the five core services (Executive, Science, Data, Communications, and Education and Training) provided by the NW CSC in support of the stated vision: Our Vision: To become nationally recognized as a best-practice model for the provision

  13. Quo vadis NW Black Sea benthic ecosystems?

    Science.gov (United States)

    Traian Gomoiu, Marian

    2016-04-01

    The author briefly presents a general review on the evolution trends of benthic ecosystems at the Romanian Black Sea coast, referring to some recent data from the literature. The Black Sea represents a "unicum hydrobiologicum" by some of its basic characteristics, such as: 1. a large semi-enclosed basin with an intense exchange of waters; 2. a sea receiving a large amount of fresh water, especially in its northwestern sector, brought by the Danube, Dnieper and Dniester Rivers; 3. a large meromictic sea - euxinic-azoic below depths of 150 - 200 m; 4. around the sea there is a large filter-holding belt consisting of bivalves (Mytilus galloprovincialis and Modiolula phaseolina); 5. a sea having in its northwestern sector a large area covered by red algae of the genus Phyllophora; 6. a sea undergoing, in the last 50 years, intense environmental pressures (pollution by large rivers and direct discharges of wastewater from urban areas, the development of maritime traffic, overfishing by bottom trawling, coastal facilities and especially by many defense works of the new port); 7. a sea registering in the last decades of the past century many events of eutrophication; 8. a sea enriching its biodiversity by alien species. After the political and socio-economic changes triggered by the events of 1989 and especially after Romania's accession to EU, the state of the northwestern Black Sea coastal ecosystems, has recorded positive changes: • Decrease in environmental pressures; • Decreasing pollutant / fertilizing discharges into the Danube; • Reduction of domestic sewage quantities from coastal settlements; • Improvement in the quality of the wastewater discharged into the sea; • Reduction of active fishing by bottom trawling; • Adopting and implementing a national / international set of guidelines concerning marine environment; • Adopting regulations on the protection of the marine environment against pollution in marine economy: transport / shipping, tourism

  14. Coronal radiation belts

    CERN Document Server

    Hudson, H S; Frewen, S F N; DeRosa, M L

    2009-01-01

    The magnetic field of the solar corona has a large-scale dipole character, which maps into the bipolar field in the solar wind. Using standard representations of the coronal field, we show that high-energy ions can be trapped stably in these large-scale closed fields. The drift shells that describe the conservation of the third adiabatic invariant may have complicated geometries. Particles trapped in these zones would resemble the Van Allen Belts and could have detectable consequences. We discuss potential sources of trapped particles.

  15. Dunlop Enerka Belting supplies and installs Europe's longest conveyor belt at British Coal-Mine

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ Dunlop Enerka Belting of Farington, U.K., has supplied a steel cord conveyor belt to the mine complex at Selby in North Yorkshire operated by RJB Mining plc. The new conveyor belt replaces the belt supplied and installed in 1981 by Dunlop Enerka Belting (then BTR Belting Ltd.).

  16. Deformation Characters of the Maowen Fault Belt in Longmenshan,Western Sichuan

    Institute of Scientific and Technical Information of China (English)

    TANG Zemin; ZHANG Yueqiao; YANG Nong

    2001-01-01

    The Maowen fault belt is one of important fault belts of the intercontinental orogenic belt of Longmenshan, mainly experienced three stage deformation; they are ductile shearing of thrust napping, brittle thrust napping and sinstral strike-slipping. Although Sc strike of mylonite formed by ductile shearing in early stage was reformed by later two stage brittle deformation, and changed greatly along the strike and inclination, the shear zone, as a whole, strikes NE and inclines NW. The stretching lineation is parallel or nearly parallel to the inclination of the ductile shear zone. According to the development of conjugated joints, the main compressive stress of the two stage brittle deformation is oriented to 306°and 2°, respectively.

  17. Properties of a gay hydrate province on a subduction-collision related margin off Sabah, NW Borneo (POPSCOMS)

    Science.gov (United States)

    Behain, D.; Fertig, J.; Meyer, H.; Franke, D.; Barckhausen, U.

    2003-04-01

    In 2001, during the scientific survey BGR01 (POPSCOMS) more than 2900 km of seismic, magnetic, gravimetric data were acquired. One of the targets of the survey BGR01 was the gathering of supplementary data for a detailed study of the occurrence and properties of gas hydrates off NW Sabah. For the subsequent AVA-analysis (Amplitude Versus Angle) at the BSRs more than 1400 km of high resolution MCS-lines with a 6 km long streamer (480 channels, sample rate 1 ms, record length 7 s, shot distance 25 m) have been acquired. Due to the different structural settings and sedimentation histories the continental margin off NW Sabah have been subdivided into different tectonostratigraphic provinces (NW Sabah Platform, NW Sabah Trough, Baram Delta Thrust Belt zone, Lower Tertiary Thrust Sheet, Outboard Belt and Inboard Belt). The BSR occurrences off Sabah are mainly linked with structural and tectonic features and are focused in the folded, thrusted, and uplifted structures. They occur in the post-Miocene sediments between 250 and 300 m beneath the seafloor, in water depths between 1100 and 2800 m. The BSRs have been observed in the Baram Delta Thrust Belt zone, the Compressed Thrust Toe, Lower Tertiary Thrust Sheets and for the first time in the NW Sabah Trough. The BSRs occur mainly in the hanging walls of the individual thrust sheets which form anticline-like structures. Due to the tectonically controlled morphology of the seafloor the distribution of BSRs consists of elongated bodies with a maximal length of 190 km and an average lateral extent of 5 km, which run mainly parallel to each other. We have assumed 3 models for the origin of BSRs in the MCS lines (BSRs are caused 1. only by existence of free gas below the BSRs, 2. only by hydrate above the BSRs, 3. a combination of 1 and 2). To restore amplitudes at the BSRs, source and receiver directivity are explicitly considered. The source-receiver offset that is in most cases 5 times the target depth provides incidence

  18. DEFORMATION CHARACTERISTICS AND ESR DATING OF ANHUA-XUPU FAULT BELT IN THE XUEFENG MOUNATAINS,HUNAN

    Institute of Scientific and Technical Information of China (English)

    YANG Kuifeng; YANG Kunguang; MA Changqian

    2005-01-01

    Anhua-Xupu fault belt plays a very important role in the formation of Xuefeng Mountains. The fault belt shows an arc-structure extruding towards NW. Fault rocks, microstructures and homogeneous temperature (concentrated around 160°C) of fluid inclusions in the quartz veins shows that the fault belt mainly underwent shallow brittle deformation and the highest-grade dynamic metamorphic rock is mylonitized sericite phyllite. The ESR (Electron Spin Resonance) dating from the quartz veins in the fault rocks shows that the fault belt underwent two intense fluid movement stages at Yanshanian (156.9~136.2Ma, 119.8~90.6Ma); moreover not only the occurrence and microstructures but also the homogeneous temperature of the quartz veins developed in that two stages show obvious diversity,which can prove that there exists the reversion period of Mesozoic extension and compression movement of Xuefeng mountains between these two stages.

  19. Magmatic Conduit Metallogenic System in Jinchuan Cu-Ni (PGE) Sulfide Deposit

    Science.gov (United States)

    Su, S.; Tang, Z.; Zhou, M.; Song, C.

    2014-12-01

    The Jinchuan Cu-Ni (PGE) sulfide deposit is located in the southwestern margin of North China Craton. Jinchuan ultramafic intrusion hosts the third largest magmatic Cu-Ni deposit in the world. There are mainly four orebodies, namely, orebody-58, orebody-24, orebody-1, and orebody-2, respectively from west to east in the deposit. The primary characteristics of Jinchuan Cu-Ni sulfide deposit are the following: (1) There is an obvious boundary between orebodys and country rocks, usually orebodys intruded into country rocks. (2) "sulfide melts" migrate and settle in the later stage of magma evolution. (3) Fluid Minerals Assemblages are found in the sulfide ores, there is Phl+Cc+Pn+Ccp+Po in orebody-2; Phl+Dol+AP+Pn+Ccp+Po in orebody-24; Q+Mag+AP+Pn+Ccp+Po in orebody-58. (4) Massive sulfides mainly occur in orebody-2, and its PGE content is very rare. Pt-Pd enrichment zones mainly occur in orebody-1; orebody-24 and orebody-58. Ir vs. Ru, Rh, Pt, Pd show positive relationship in orebody-2, but Ir vs. Ru, Rh show positive relationship, Ir vs. Pt, Pd exhibit negative relationship in orebody-1, orebody-24 and orebody-58. The modeling of Ir-Pd shows that the massive sulfide in orebody-2 maybe the origin of MSS. Pt-Pd enrichment zones in orebody-1 orebody-24 and orebody-58 are the relic liquid of monosulfide solid solution segregation; (5) Cu/Ni value is 1.24 in orebody-58, 1.56 in orebody-24, 1.83 in orebody-1, and 2.06 in orebody-2. These features imply that (1) "ore magma" or "melt-fluid bearing metal" formed in the staging chamber in depth; (2) "ore magma" might contain a lot of fluids; (3) "melt-fluid bearing metal" flow moves as a whole; (4) The moving direction of melt-fluid bearing metal flow is form west to east. The ores are enriched in Ni in the front, and enriched in Cu, Pt, Pd in the back of Jinchuan Magmatic Conduit Metallogenic System.

  20. Geochemistry of magnetite from Proterozoic Fe-Cu deposits in the Kangdian metallogenic province, SW China

    Science.gov (United States)

    Chen, Wei Terry; Zhou, Mei-Fu; Gao, Jian-Feng; Hu, Ruizhong

    2015-10-01

    Fe-Cu deposits in the Kangdian Fe-Cu metallogenic province, SW China, are hosted in Paleoproterozoic meta-volcanic-sedimentary sequences and are spatially associated with coeval mafic intrusions. Several well-known examples are the giant Lala, Dahongshan, and Yinachang deposits. They have a common paragenetic sequence of an early Fe-oxide stage associated with sodic alteration and a late Cu-sulfide stage associated with potassic-carbonate alteration. Magnetite dominates the Fe-oxide stage of these deposits but is also present in the Cu-sulfide stage of the Lala deposit. This study uses trace element compositions of magnetite to examine the nature and origin of the ore-forming fluids. The magnetite has variable concentrations of Ti, Al, Mg, Mn, Si, V, Cr, Ca, Co, Ni, Sc, Zn, Cu, Mo, Sn, and Ga, which are thought to have been controlled mainly by fluid compositions and/or intensive parameters (e.g., temperature and oxygen fugacity ( fO2)). Fluid-rock interaction and coprecipitating mineral phases appear to be less important in controlling the magnetite compositions. Magnetite grains in the Fe-oxide stage of the Lala and Dahongshan deposits have comparable trace element compositions and were likely precipitated from chemically similar fluids. High Ni contents of magnetite in both deposits, coupled with previous isotopic data and the fact that the two deposits are spatially associated with coeval mafic intrusions, strongly suggest that the ore-forming fluids were genetically related to the mafic magmas that formed the intrusions. Magnetite grains in the Fe-oxide stage of the Yinachang deposit have much lower V and Ni but higher Sn and Mo contents than those of the Lala and Dahongshan deposits and are thus thought to have precipitated from more oxidized and Mo-Sn-rich fluids that may have evolved from relatively felsic magmas. Magnetite grains from the Cu-sulfide and Fe-oxide stages of the Lala deposit are broadly similar in composition, but those in the Cu

  1. DESIGN TRENDS IN TIMING BELTS

    Directory of Open Access Journals (Sweden)

    Grzegorz DOMEK

    2014-03-01

    Full Text Available Paper presents the state of the art gear with timing belts. Areas of use pose new challenges for designers gear. It has materials and technologies used in the production. Has been developed algorithm of design timing belts to new applications

  2. Geography of the asteroid belt

    Science.gov (United States)

    Zellner, B. H.

    1978-01-01

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

  3. Large clusters of gold deposits and large-scale metallogene-sis in the Jiaodong Peninsula, Eastern China

    Institute of Scientific and Technical Information of China (English)

    ZHAI; Mingguo

    2001-01-01

    [1]Tu, G. C., The unique nature in ore deposition, geological background and metallogenic mechanism of non-conventional superlarge ore deposits: A preliminary discussion, Science in China (in Chinese), Ser. D, 1998, 41 (sup.): 1-6.[2]Pei, R. F., Qiu, X. P., Yin, B. C. et al., The Explosive anomaly of ore-forming processes and super-accumulation of metals, Mineral Deposits (in Chinese), 1999, 18 (4): 333-340.[3]Zhai, Y. S., De, J., Li, X. B., Essentials of Metallogeny (in Chinese), Beijing: Geological Publishing House, 1999: 1-288.[4]Mao, J. W., Hua, R. M., Li, X. B., A preliminary study of large-scale metallogenesis and large clusters of mineral deposits, Mineral Deposits (in Chinese), 1999, 18(4): 291-298.[5]Zhang, C. H., Gu, D. L., Study on the microstructure and deformation mechanism of the sinistral slick ductile shear zone in the middle of the northern Jiaonan uplift, in Tectonic and Geological Evolution of the Northern Jiaonan Uplift (in Chi-nese) (eds. Gu, D. L., Zhang, C. H.), Beijing: China University of Geosciences Press, 1996, 96-104.[6]Zhai, M. G., Guo, J. H., Wang, Q. C. et al., Division of geological-tectonic units in the northern Sulu ultra-high pressure zone: An example of thick-skin thrust of crystalline units, Scientica Geologica Acta (in Chinese), 2000, 35(1): 16-26.[7]Zhai, M. G., Guo, J. H., Cong, B. L. et al., Sm-Nd geochronolgy and petrography of garnet pyroxene granulites in the northern Sulu region and their geotectonic implication, Scientica Geologica Acta (in Chinese), 1999, 34(3): 301-310.[8]Zhai, M. G., Cong, B., Guo, J., Sm-Nd geochronology and petrography of garnet pyroxene granulites in the northern Sulu region of China and their geotectonic implication, Lithos, 2000, 52: 23-33.[9]Jahn, B. M., Geochemical and isotopic study of UHP terrain in China (abstract), in First Workshop on UHP Metamor-phism and Tectonics, Stanford: Stanford University, 1994, A71-74.[10]Li, S. G., Jagoutz

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

    Science.gov (United States)

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

    2016-04-01

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

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

    Science.gov (United States)

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

    2009-05-01

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

  6. AUTOMATION OF CONVEYOR BELT TRANSPORT

    Directory of Open Access Journals (Sweden)

    Nenad Marinović

    1990-12-01

    Full Text Available Belt conveyor transport, although one of the most economical mining transport system, introduce many problems to mantain the continuity of the operation. Every stop causes economical loses. Optimal operation require correct tension of the belt, correct belt position and velocity and faultless rolls, which are together input conditions for automation. Detection and position selection of the faults are essential for safety to eliminate fire hazard and for efficient maintenance. Detection and location of idler roll faults are still open problem and up to now not solved successfully (the paper is published in Croatian.

  7. A review of mineral systems and associated tectonic settings of northern Xinjiang, NW China

    Directory of Open Access Journals (Sweden)

    Franco Pirajno

    2011-04-01

    Full Text Available In this paper we present a review of mineral systems in northern Xinjiang, NW China, focussing on the Tianshan, West and East Junggar and Altay orogenic belts, all of which are part of the greater Central Asian Orogenic Belt (CAOB. The CAOB is a complex collage of ancient microcontinents, island arcs, oceanic plateaux and oceanic plates, which were amalgamated and accreted in Early Palaeozoic to Early Permian times. The establishment of the CAOB collage was followed by strike-slip movements and affected by intraplate magmatism, linked to mantle plume activity, best exemplified by the 250 Ma Siberian Traps and the 280 Ma Tarim event. In northern Xinjiang, there are numerous and economically important mineral systems. In this contribution we describe a selection of representative mineral deposits, including subduction-related porphyry and epithermal deposits, volcanogenic massive sulphides and skarn systems. Shear zone-hosted Au lodes may have first formed as intrusion-related and subsequently re-worked during strike-slip deformation. Intraplate magmatism led to the emplacement of concentrically zoned (Alaskan-style mafic–ultramafic intrusions, many of which host orthomagmatic sulphide deposits. A huge belt of pegmatites in the Altay orogen, locally hosts world-class rare metal deposits. Roll-front, sandstone-hosted U mineralisation completes the rich mineral endowment of the northern Xinjiang terranes.

  8. Seat Belt Use and Stress in Adolescents.

    Science.gov (United States)

    Schichor, Aric; And Others

    1990-01-01

    Explored adolescent seat belt use and psychosocial risk factors in urban minority population (n=541). Found seat belt use reported by 49 percent of respondents. Those reporting no or intermittent seat belt use were significantly more likely than seat belt users to feel down, have decreased home support, have problems with school and the law, and…

  9. 49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Seats, seat belt assemblies, and seat belt... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses... the driver's seat and seat belt assembly anchorages that conform to the location and...

  10. Chaos on the conveyor belt

    CERN Document Server

    Sándor, Bulcsú; Tél, Tamás; Néda, Zoltán

    2013-01-01

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

  11. Structural Geochemical Study of the Yuxi Fold-Thrust Belt in the Southern North China Plate

    Institute of Scientific and Technical Information of China (English)

    Li Wenyong; Xia Bin; Li Dongxu

    2006-01-01

    The Yuxi (豫西) fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. The analysis of chemical compositions and new stress minerals indicates: extending from the surrounding country rocks to the center of the fracture belt, the Fe2 O3 content gradually increases while the FeO content gradually decreases; regular increase, decrease or peak changes are shown for chemical compositions likeSiO2, Al2O3, Fe2O3, MgO, CaO, FeO, loss on ignition, TiO2,K2O, Na2O, etc.. New stress minerals are developed for the south branch and few for the north branch.The characteristics of chemical compositions and new stress minerals of the thrust fracture demonstrate that the fracture belt has undergone a process from a closed reducing environmental system to a relatively open, oxidizing environmental system, and compressive fractures have resulted from compression in the late stages of evolution, and the dynamothermal metamorphism and thrusting intensities are different between the south and north branches of the belt, which is strong for the south branch but relatively weak for the north branch.

  12. Ore-controlling Factors and a Metallogenic Model for the Xianglushan Tungsten-Ore Field in Northern Jiangxi Province%赣北香炉山钨矿田矿床控制因素及成矿模式

    Institute of Scientific and Technical Information of China (English)

    陈波; 周贤旭

    2012-01-01

    The Xianglushan tungsten-ore field is part of the Jiuling-Zhanggongshan W-Sn metallogenic belt in northern Jiangxi Province. Combining the ore field exploration in recent years, this paper researches the ore-controlling factors on the basis of geological background of this ore field. The result shows that the impure limestone combination in the Upper Sinian and Cambrian strata is closely related to mineralization in the area. Folds are the major controlling structures in the ore field. Faults and interlayer fracture zones control the ore body position. The Yanshanian magmatic activities provided ore -forming material sources and played an important role in the process of ore fluid migration and deposition. The main ore bodies, hosted in the pyroxene -biotite metamorphic belt, are related to greisenization alteration. This article establishes a metallogenetic model for the Xainghushan tungsten ore field. It may have important guiding significance for the prediction of ore deposit and resources prospecting and exploitation. It can be also used as a reference in searching for similar deposits in the southern margin of the Yangtze Plate.%香炉山矿田是赣北九岭—鄣公山钨锡成矿带的组成部分。本文结合近年来矿田的勘查找矿成果,在分析矿田地质背景的基础上,研究了矿床的控矿因素。认为该区震旦系上统和寒武系地层中的不纯灰岩类组合与成矿关系密切,控制矿田的主体构造是褶皱;断裂及层间破碎带控制矿体的定位,燕山期岩浆活动不仅提供成矿物质来源;同时在矿液的运移和淀积过程中发挥了重要作用,主要矿体均赋存在透辉石—黑云母变质带并与云英岩化等蚀变有关,在此基础上建立了成矿模式。对矿田下步的矿床预测和勘查开发具有重要的指导意义。同时,对扬子板块南缘相似类别矿床的找矿工作起着一定的借鉴作用。

  13. Neoproterozoic collision tectonics in the Mozambique Belt of East Africa: evidence from the Uluguru mountains, Tanzania

    Science.gov (United States)

    Muhongo, Sospeter

    1994-10-01

    The fault-bounded Proterozoic metamorphic terranes lying to the E of the Tanzanian craton make up the Usagara tectonic domain and are a part of the transcontinental Mozambique Orogenic Belt (MB). The lithotectonic units in the MB of the East Africa consist of comparable rock assembles which underwent the same complex deformational history and are thought to represent large thrust sheets or nappes. Their shelf- and fore-deep terranes border the Tanzanian craton and make up the foreland terranes of the Pan-African Mozambique Belt. Granulite-gneiss nappes are ubiquitous in the orogen. Granulite-facies metamorphism, associated with recumbent folds, was due to crustal thickening, which took place during the collision between Gondwana fragments. Isotope data suggest a collision (and concomitant granulite-facies metamorphism) age of between 700 and 550 Ma. The orientations of planar and linear fabrics in the granulite-facies rocks of the Uluguru mountains are used to infer the relative crustal block motions during this collisional event. This Pan-African collisional event was characterized by NW-directed movements, oblique to the N-S trend of the orogen, and involved SE-directed backthrusting. The Ubendian Belt of Tanzania and the Aswa Shear Zone in Uganda and Kenya, which both bifurcate around the Tanzania craton, accommodated the tectonically thickened crust, created by the collisional event, through NW-SE sinistral strike-slip movements.

  14. 40Ar-39Ar Age and Geological Significance of the Sawur Gold Belt in Northern Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    SHEN Ping; SHEN Yuanchao; ZENG Qingdong; LIU Tiebing; LI Guangming

    2005-01-01

    The 40Ar-39Ar age method is employed in this work to analyze fluid inclusions of quartz in the ore bodies from the Kuo'erzhenkuola and Bu'erkesidai gold deposits in the Sawur gold belt, northern Xinjiang. The results show that the main mineralization occurred in 332.05±2.02-332.59±0.51 Ma and 335.53±0.32 Ma-336.78±0.50 Ma for the Kuo'erzhenkuola and Bu'erkesidai gold deposits respectively, indicating that the two deposits are formed almost at the same time, and the metallogenic time of the two deposits are close to those of the hosting rocks formed by volcanic activity of the Sawur gold belt. This geochronological study supplies new evidence for determining the timing of gold mineralization, the geneses of gold deposits, and identifies that in the Hercynian period, the Altay area developed a tectonic-magmatic-hydrothermal mineralization of the Early Carboniferous period, except the two known mineralization periods including the tectonic-magmatic-hydrothermal mineralization of the Devonian period and Late CarboniferousPermian period.

  15. Northern Belt of Jupiter

    Science.gov (United States)

    2000-01-01

    [figure removed for brevity, see original site] A four-panel frame shows a section of Jupiter's north equatorial belt viewed by NASA's Cassini spacecraft at four different wavelengths, and a separate reference frame shows the location of the belt on the planet.A fascinating aspect of the images in the four-panel frame is the small bright spot in the center of each. The images come from different layers of the atmosphere, so the spot appears to be a storm penetrating upward through several layers. This may in fact be a 'monster' thunderstorm, penetrating all the way into the stratosphere, as do some summer thunderstorms in the midwestern United States. These images were taken on Nov. 27, 2000, at a resolution of 192 kilometers (119 miles) per pixel. They have been contrast-enhanced to highlight features in the atmosphere.The top panel of the four-panel frame is an image taken in a near-infrared wavelength at which the gases in Jupiter's atmosphere are relatively non-absorbing. Sunlight can penetrate deeply into the atmosphere at this wavelength and be reflected back out, providing a view of an underlying region of the atmosphere, the lower troposphere.The second panel was taken in the blue portion of wavelengths detected by the human eye. At these wavelengths, gases in the atmosphere scatter a modest amount of sunlight, so the clouds we see tend to be at somewhat higher altitudes than in the top panel.The third panel shows near-infrared reflected sunlight at a wavelength where the gas methane, an important constituent of Jupiter's atmosphere, absorbs strongly. Dark places are regions without high-level clouds and consequently large amounts of methane accessible to sunlight. Bright regions are locations with high clouds in the upper troposphere shielding the methane below.The bottom panel was taken in the ultraviolet. At these very short wavelengths, the clear atmosphere scatters sunlight, and hazes in the stratosphere, above the troposphere, absorb sunlight. That

  16. Metallogenic system of Machangqing Cu-Mo-Au polymetallic ore concentration area in Yunnan Province%云南省马厂箐Cu-Mo-Au多金属矿集区成矿系统

    Institute of Scientific and Technical Information of China (English)

    郭晓东; 牛翠袆; 王治华; 王梁; 夏锐

    2012-01-01

    As a typical porphyry Cu-Mo-Au ore concentration area related to alkaline-rich intrusive rocks in western Yunnan ore belt, Machangqing has many mineralization types such as porphyry Cu-Mo mineralization, contact metasomatic Cu-Mo-Au mineralization and hydrothermal Au-Ag-Pb-Zn lodes. Alteration-mineralization types and ore-forming element associations show clear spatial zones around the porphyry. The magmatic activity is synchronous to Cu-Mo-Au mineralization. The three types are genetically controlled by the Machangqing porphyry magma system which supplied material, fluid and dynamic force for the mineralization. Based on a detailed analysis of the mineralization evidence and the structure of the ore system, the authors have concluded that the thermal dynamic force from Machangqing intrusion caused the migration of the are-forming fluid from the magma outwards, With the variation of physical and chemical conditions of fissures in the intrusive body as well as contact structures and fracture zones in the wall rock, there occurred different mineralization types and metallogenic element associations under different conditions. In general, with the evolution of hydrothermal mineralization, the mineralization was developed from porphyry through the contact zone to the wall rock, and from high-T to low-T correspondingly. The establishment of the Cu-Mo-Au polymetallic metallogenic system for the Machangqing ore concentration area will help the study of mineralization theory and the exploration practice in the west Yunnan metallogenic belt.%马厂箐地区是滇西成矿带内一个典型的与喜马拉雅期富碱侵入岩有关的斑岩型铜-钼-金多金属矿集区,发育有斑岩型钼铜、接触交代型铜钼(金)和热液脉型金银铅锌等多种类型矿化.其矿化和蚀变类型及成矿元素组合,在空间上具有明显的以岩体为中心的分带性;岩浆活动与铜钼金成矿作用具有同时性.这3种矿化类型的形成受控于马厂箐

  17. Effects of vehicle seat and belt geometry on belt fit for children with and without belt positioning booster seats.

    Science.gov (United States)

    Reed, Matthew P; Ebert-Hamilton, Sheila M; Klinich, Kathleen D; Manary, Miriam A; Rupp, Jonathan D

    2013-01-01

    A laboratory study was conducted to quantify the effects of belt-positioning boosters on lap and shoulder belt fit. Postures and belt fit were measured for forty-four boys and girls ages 5-12 in four highback boosters, one backless booster, and on a vehicle seat without a booster. Belt anchorage locations were varied over a wide range. Seat cushion angle, seat back angle, and seat cushion length were varied in the no-booster conditions. All boosters produced better mean lap belt fit than was observed in the no-booster condition, but the differences among boosters were relatively large. With one midrange belt configuration, the lap belt was not fully below the anterior-superior iliac spine (ASIS) landmark on the front of the pelvis for 89% of children in one booster, and 75% of children failed to achieve that level of belt fit in another. In contrast, the lap belt was fully below the ASIS for all but two children in the best-performing booster. Child body size had a statistically significant but relatively small effect on lap belt fit. The largest children sitting without a booster had approximately the same lap belt fit as the smallest children experienced in the worst-performing booster. Increasing lap belt angle relative to horizontal produced significantly better lap belt fit in the no-booster condition, but the boosters isolated the children from the effects of lap belt angles. Reducing seat cushion length in the no-booster condition improved lap belt fit but changing cushion angle did not. Belt upper anchorage (D-ring) location had a strong effect on shoulder belt fit in conditions without shoulder belt routing from the booster. Unexpectedly, the worst average shoulder belt fit was observed in one highback booster with a poorly positioned shoulder belt routing clip. The shoulder belt was routed more outboard, on average, with a backless booster than without a booster, but raising the child also amplified the effect of D-ring location, such that children were

  18. Mesozoic and Cenozoic tectonic evolution of the Longmenshan fault belt

    Institute of Scientific and Technical Information of China (English)

    WANG; ErChie

    2009-01-01

    The giant earthquake(Ms=8.0) in Wenchuan on May 12,2008 was triggered by oblique convergence between the Tibetan Plateau and the South China along the Longmenshan fault belt.The Longmenshan fault belt marks an important component of the tectonic and geomorphological boundary between the eastern and western part of China and has a protracted tectonic history.It was first formed as an intracontinental transfer fault,patitioning the differential deformation between the Pacific and Tethys tectonic domains,initiated in late Paleozoic-early Mesozoic time,then served as the eastern boundary of the Tibetan Plateau to accommodate the growth of the plateau in Cenozoic.Its current geological and geomorphological frameworks are the result of superimposition of these two tectonic events.In Late Triassic,the Longmenshan underwent left-slip oblique NW-SE shortening due to the clockwise rotation of the Yangtze Block,which led to the flexural subsidence of the Sichuan foreland basin,but after that,the subsidence of the Sichuan Basin seems no longer controlled by the tectonic activity of the Longmenshan fault belt.The Meosozoic tectonic evolution of the Songpan-Ganzi fold belt differs significantly compared with that of the Yangtze Platform,featured by intensive northeast and southwest shortening and resulted in the close of the Paleo-Tethys.Aerial photos taken immediately after main shock of the giant May 12,2008 earthquake have documented extensive rock fall and landslides that represent one of the most destructive aspects of the earthquake.Both rock avalanches and landslides delivered a huge volume of debris into the middle part of the Minjiang River,and formed many dammed lakes.Breaching of these natural dams can be catastrophic,as occurred in the Diexi area along the upstream of the Minjiang River in the year of 1933 that led to devastating floodings.The resultant flood following the breaching of these dams flowed through and out of the Longmenshan belt into the Chengdu Plain

  19. Mesozoic and Cenozoic tectonic evolution of the Longmenshan fault belt

    Institute of Scientific and Technical Information of China (English)

    WANG ErChie; MENG QingRen

    2009-01-01

    The giant earthquake (MS=8.0) in Wenchuan on May 12, 2008 was triggered by oblique convergence between the Tibetan Plateau and the South China along the Longmenshan fault belt. The Longmenshan fault belt marks an important component of the tectonic and geomorphological boundary between the eastern and western part of China and has a protracted tectonic history. It was first formed as an intracontinental transfer fault, patitioning the differential deformation between the Pacific and Tethys tectonic domains, initiated in late Paleozoic-early Mesozoic time, then served as the eastern boundary of the Tibetan Plateau to accommodate the growth of the plateau in Cenozoic. Its current geological and geomorphological frameworks are the result of superimposition of these two tectonic events. In Late Triassic, the Longmenshan underwent left-slip oblique NW-SE shortening due to the clockwise rotation of the Yangtze Block, which led to the flexural subsidence of the Sichuan foreland basin, but after that, the subsidence of the Sichuan Basin seems no longer controlled by the tectonic activity of the Longmenshan fault belt. The Meosozoic tectonic evolution of the Songpan-Ganzi fold belt differs significantly compared with that of the Yangtze Platform, featured by intensive northeast and southwest shortening and resulted in the close of the Paleo-Tethys. Aerial photos taken immediately after main shock of the giant May 12, 2008 earthquake have documented extensive rock fall and landslides that represent one of the most destructive aspects of the earthquake. Both rock avalanches and landslides delivered a huge volume of debris into the middle part of the Minjiang River, and formed many dammed lakes. Breaching of these natural dams can be catastrophic, as occurred in the Diexi area along the upstream of the Minjiang River in the year of 1933 that led to devastating floodings. The resultant flood following the breaching of these dams flowed through and out of the Longmenshan belt

  20. 栾川县罗村钼矿成矿地质背景和矿床特征%Metallogenic Geologic Background and Characteristics of Luocun Molybdenum Deposit in Luanchuan County , Henan Province

    Institute of Scientific and Technical Information of China (English)

    张自森

    2011-01-01

    栾川县罗村钼矿为豫西东秦岭钼成矿带的重要组成部分,地处华北地台-华熊台缘坳陷-卢氏至栾川陷褶束内.区内太华群变质岩和熊耳群火山岩广泛发育,构造活动强烈,岩浆活动频繁,成矿地质条件有利.通过对矿区地质及矿床地质特征的分析,认为罗村斑岩体由中心细粒花岗斑岩、中环带角砾岩和外环带花岗闪长岩组成,罗村钼矿主要位于中环带角砾岩中.通过综合分析,认为罗村钼矿床形成于燕山中-晚期,陆内造山俯冲作用导致下地壳熔融与地幔楔分熔,形成富钼熔浆.其沿黑沟-栾川断裂带多次上侵,在罗村附近形成斑岩体.晚期岩浆期后热液对中环带角砾岩进行充填和交代,形成斑(角砾)岩型罗村钼矿床.%Luocun molybdenum deposit of Luanchuan county is an important part of the eastern Qinling molybdenum metallogenic belt in western Henan, it is located on the Lushi-Luanchuan depression folds bundle, that is a part of the Huaxiong margin depression in the North China Platform. The volcanic rocks of the Xiong' er Group and the metamorphic rocks of Taihua Group in the research area distribute extensively. For the intense tectonic movements and frequent magmatic activities, it is considered to be a favorable metallogenic area. Through the study of the characteristics of the geology in mining area and deposit, we know the Luocun granite-porphyry bodies are composed of fine granite-porphyry centre, breccia middle zones and Granodiorite rock outer zones, and the Luocun molybdenum deposit occur in breccia middle zones. It is concluded that the Luocun molybdenum deposit was formed during Later Yanshanian to middle Yanshanian. The intracontinental orogenesis and subduction result in the fusion of lower crust and the liquation of mantle wedge form the molybdenum rich magma. Its uptrusion into Heigou-Luanchuan fault zones are more than once, and formed granite-porphyry body near the Luocun. Postmagmatic

  1. Kuiper Belts Around Nearby Stars

    CERN Document Server

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

    2010-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xinyuan; LUO Jinhai; WANG Qinghua

    2004-01-01

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

  3. Ore fluid geochemistry of the Jinlongshan Carlin type gold ore belt in Shaanxi Province, China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The Jinlongshan gold ore belt in southern Shaanxi Province contains a number of Carlin-type gold deposits in the Qinling collisional orogenic belt. Their fluid inclusions are of the Na+ - Cl- type. From the main metallogenic stage to later stages, the total quantity of anions and cations, temperature and deoxidation parameter (R) for fluid inclusions all gradu ally decreased, suggesting the gradual intensification of fluid oxidation, the reduction of met allogenic depth and the input of meteoric water and organic components. The deposits were formed during crustal uplifting and hence had similar tectonic settings to orogenic gold depos its. The CO2 contents and CO2/H2O values of the ore fluid increased from early to late sta ges, and the wall-rock alteration is represented by decarbonation, which is inconsistent with the characteristics of orogenic gold deposits. It is also discovered that Na + , K + ,SO42-, Cl-and the total amounts of anions and cations in the inclusions in quartz are higher than those in the coexisting calcite. The H, O and C isotope ratios indicate that the ore fluid was sourced from meteoric water and metamorphic devolatilisation of the sedimentary rocks that host the ores. The high background δ18O and δ13C values of wall rocks resulted in high δ18O and δ13 C values of ore fluid and also high δ 18 O and δ 13 C values of hydrothermal minerals such as quartz and carbonate. The carbon in ore fluid stemmed largely from the hosting strata. The δ 18O and δ13C values of Fe-calcite and the δD values of fluid inclusions are lower than those of calcite and quartz. In terms of the theory of coordination chemistry, all these differences can be ascribed to water-rock interaction in the same fluid system, instead, to the multi source of ore fluid.

  4. Timing of multiple hydrothermal events in the iron oxide-copper-gold deposits of the Southern Copper Belt, Carajás Province, Brazil

    Science.gov (United States)

    Moreto, Carolina P. N.; Monteiro, Lena V. S.; Xavier, Roberto P.; Creaser, Robert A.; DuFrane, S. Andrew; Melo, Gustavo H. C.; Delinardo da Silva, Marco A.; Tassinari, Colombo C. G.; Sato, Kei

    2015-06-01

    The Southern Copper Belt, Carajás Province, Brazil, hosts several iron oxide-copper-gold (IOCG) deposits, including Sossego, Cristalino, Alvo 118, Bacuri, Bacaba, Castanha, and Visconde. Mapping and U-Pb sensitive high-resolution ion microprobe (SHRIMP) IIe zircon geochronology allowed the characterization of the host rocks, situated within regional WNW-ESE shear zones. They encompass Mesoarchean (3.08-2.85 Ga) TTG orthogneiss, granites, and remains of greenstone belts, Neoarchean (ca. 2.74 Ga) granite, shallow-emplaced porphyries, and granophyric granite coeval with gabbro, and Paleoproterozoic (1.88 Ga) porphyry dykes. Extensive hydrothermal zones include albite-scapolite, biotite-scapolite-tourmaline-magnetite alteration, and proximal potassium feldspar, chlorite-epidote and chalcopyrite formation. U-Pb laser ablation multicollector inductively coupled mass spectrometry (LA-MC-ICP-MS) analysis of ore-related monazite and Re-Os NTIMS analysis of molybdenite suggest multiple Neoarchean (2.76 and 2.72-2.68 Ga) and Paleoproterozoic (2.06 Ga) hydrothermal events at the Bacaba and Bacuri deposits. These results, combined with available geochronological data from the literature, indicate recurrence of hydrothermal systems in the Southern Copper Belt, including 1.90-1.88-Ga ore formation in the Sossego-Curral ore bodies and the Alvo 118 deposit. Although early hydrothermal evolution at 2.76 Ga points to fluid migration coeval with the Carajás Basin formation, the main episode of IOCG genesis (2.72-2.68 Ga) is related to basin inversion coupled with Neoarchean (ca. 2.7 Ga) felsic magmatism. The data suggest that the IOCG deposits in the Southern Copper Belt and those in the Northern Copper Belt (2.57-Ga Salobo and Igarapé Bahia-Alemão deposits) do not share a common metallogenic evolution. Therefore, the association of all IOCG deposits of the Carajás Province with a single extensive hydrothermal system is precluded.

  5. Characterization of gold mineralization in Garin Hawal area, Kebbi State, NW Nigeria, using remote sensing

    Directory of Open Access Journals (Sweden)

    Talaat M. Ramadan

    2010-12-01

    Full Text Available Garin Hawal area, Kebbi State, NW Nigeria is part of the Neoproterozoic to Early Phanerozoic terrane separating the west African and Congo Cratons. Three main gold-bearing shear zones were detected in the study area from the processed Landsat ETM+ images and extensive ground investigation. Field and petrographical studies indicate that the Neoproterozoic rocks are represented by a highly folded and faulted belt constituted of hornblende, muscovite and graphite schist. They are intruded by granondiorites and late to post granitic dykes. Extensive alteration zones were identified using high resolution QuickBird image along Garin Hawal shear zone. The alteration zones and associated quartz veins are generally concordant with the main NE–SW regional structural trend and are dipping to the NW. Geochemical studies indicate that the gold content reaches 8 g/t in the alteration zones, while it reaches up to 35 g/t in the quartz veins. Mineralogical studies indicate that the alterations are strongly potassium-enriched. Pyrophyllite, kaolinite, illite, gypsum and quartz also occur. The main ore minerals are gold, chalcopyrite, arsenopyrite, pyrite, galena and iron oxides. This study indicates that the alteration zones and the associated quartz veins in the muscovite schist are promising and need more detailed exploration for Au and Ag mineralization to evaluate their potential.

  6. A Three—Stage Metallogenic Model for Gold Deposits in Metamorphosed Microclastic Rocks

    Institute of Scientific and Technical Information of China (English)

    王秀璋; 程景平; 等

    1996-01-01

    Gld deposits occurring in metamorphosed microcelastic rocks are distributed extensively at home and abroad.Some deposits of this type are of superlarge tonnage.The formation of gold deposits in metamorphosed microclastic rocks involves three stages:the sedimentary stage,the regionally metamorphic stage,and the ore-forming stage.At the first stage,microclastic sedimentary source rocks were developed in a relatively semi-enclosed reducing sea basin and were enriched in carbon,sulfur and gold.At the second stage,the gold adsorbed on organic matter and clay minerals was relesed and poorly concentrated during the destruction of organic matter and the depletion of clay minerals by regional metamorphism with increase temperature and pressure.At the third stage,a tectono-hydrothermal event took place.As a result,gold was leached from metamorphosed microclastic rocks,transported to ore depositional locus and/or mixed with gold of other sources in the course of migration,and finally precipitared as ores.Gold deposits of this type were eventually formed at the third stage,and they also can be classified as the orogenic belt type and the activation zone type.The gold deposits occurring in metamorphosed microcalastic rocks are the products of reworking processes and the influence of magmatism should be taken into consideration in some cases.

  7. Digital geologic map of the Thirsty Canyon NW quadrangle, Nye County, Nevada

    Science.gov (United States)

    Minor, S.A.; Orkild, P.P.; Sargent, K.A.; Warren, R.G.; Sawyer, D.A.; Workman, J.B.

    1998-01-01

    This digital geologic map compilation presents new polygon (i.e., geologic map unit contacts), line (i.e., fault, fold axis, dike, and caldera wall), and point (i.e., structural attitude) vector data for the Thirsty Canyon NW 7 1/2' quadrangle in southern Nevada. The map database, which is at 1:24,000-scale resolution, provides geologic coverage of an area of current hydrogeologic and tectonic interest. The Thirsty Canyon NW quadrangle is located in southern Nye County about 20 km west of the Nevada Test Site (NTS) and 30 km north of the town of Beatty. The map area is underlain by extensive layers of Neogene (about 14 to 4.5 million years old [Ma]) mafic and silicic volcanic rocks that are temporally and spatially associated with transtensional tectonic deformation. Mapped volcanic features include part of a late Miocene (about 9.2 Ma) collapse caldera, a Pliocene (about 4.5 Ma) shield volcano, and two Pleistocene (about 0.3 Ma) cinder cones. Also documented are numerous normal, oblique-slip, and strike-slip faults that reflect regional transtensional deformation along the southern part of the Walker Lane belt. The Thirsty Canyon NW map provides new geologic information for modeling groundwater flow paths that may enter the map area from underground nuclear testing areas located in the NTS about 25 km to the east. The geologic map database comprises six component ArcINFO map coverages that can be accessed after decompressing and unbundling the data archive file (tcnw.tar.gz). These six coverages (tcnwpoly, tcnwflt, tcnwfold, tcnwdike, tcnwcald, and tcnwatt) are formatted here in ArcINFO EXPORT format. Bundled with this database are two PDF files for readily viewing and printing the map, accessory graphics, and a description of map units and compilation methods.

  8. Evolución metalogenética de las Sierras Pampeanas de Córdoba y sur de Santiago del Estero: Ciclos famatiniano, gondwánico y ándico Metallogenic evolution of the Sierras Pampeanas of Córdoba and south of Santiago del Estero: Famatinian, Gondwanic and Andean cycles

    Directory of Open Access Journals (Sweden)

    D. Mutti

    2005-09-01

    hydrothermal fluid migration and the generation and reactivation of the main structures. At the same time, transformations occurred in deposits of Cr (Fe-Ti, Cu (Au-Ag, Pb-Zn (Ag-Cu-Au, Fe and Cu-Fe (Zn-Au-Ag-Co, and Be-Nb-Ta-W-P-U-ETR -rich pegmatites originated, together with biextended deposits of W-Bi (Mo-Cu-Sn-Zn-Au-B-F-Te, of U in association with granitoids, metasomatic deposits of Fe-Cu (Ti-Au, and Au (Cu-Zn-Pb-As rich veins and Ag-Pb-Zn (V-Sn-Mn-Cd-Au-Cu-As-Bi-Sb-Co rich veins. These deposits are correlated with those of orogenic belts. In the course of metallogenic stage 4, corresponding to the Gondwanic extensional cycle and related to the early opening of the Atlantic rift, Mn (Fe-F-Ba -rich veins, and F (Fe-Mn -rich veins were formed in association with granitoids. Metallogenic stage 5 developed during the Andean compressive cycle, generating epithermal Au occurrences, and deposits and occurrences of U-V (Mn-Fe in sedimentary rocks. The successive stages of deposition and mobilization of metallic elements determined mineralized belts in this part of Sierras Pampeanas giving birth to a specialized domain in Cr, W, Fe, Cu, Zn, Pb, Ti, Au, Bi, Be, Li, U, Mn, F and B, with Sn, Mo, ETR, Ta, Nb, V, Cd, Ag, Sb, Co, P, As, S, Te, Se and Ba subordinated.

  9. Permo-Triassic structural evolution of the Shiwandashan and Youjiang structural belts, South China

    Science.gov (United States)

    Li, Jianhua; Zhao, Guochun; Johnston, Stephen T.; Dong, Shuwen; Zhang, Yueqiao; Xin, Yujia; Wang, Wenbao; Sun, Hanshen; Yu, Yingqi

    2017-07-01

    We conducted field mapping coupled with radiometric dating across the Shiwandashan and Youjiang structural belts (SWSB and YJSB), to investigate how southwest South China evolved and to better understand its links to plate boundary dynamics during the Late Permian to Middle Triassic. Our results reveal an episodic tectono-magmatic evolutionary history of the SWSB and YJSB. The SWSB underwent significant NW-SE shortening punctuated by ∼250-240 Ma S-type pluton emplacement during the Late Permian to Middle Triassic; the shortening was expressed by thin-skinned NW-verging thrusts and folds, and conjugate sets of ∼N-trending sinistral and ∼E-trending dextral faults. The NW-SE shortening overlapped with, and was succeeded by Triassic NE-SW shortening in the YJSB. The NE-SW shortening was expressed by NE-verging thrusts and folds, which documented a northeastward propagation of foreland deformation. The NE-verging folds overprinted older NW-verging folds, forming superimposed folds at the juncture of the YJSB and SWSB in the Long'an area. Our results, combined with regional considerations, support a model of the NW-SE shortening as an Andean-type orogeny that developed in response to westward subduction of the Paleo-Pacific Plate, and the NE-SW shortening as a product of the Indochina-South China collision. The subduction of the Paleo-Pacific plate assisted in westward motion of the South China oceanic lithosphere, which may have facilitated the closure of the Paleo-Tethys ocean and subsequent collisions of South China with North China and Indochina.

  10. Evidence for Metallogenic Geochemistry of Volcano-Hot Spring Deposition in Xiqiu Copper deposit,Zhejiang Province,China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There were strong volcanic and hot spring activities in Late proterozic in the Xiqiu mining district,Zhejiang province,The volcanic rocks and hydrothermal sedimentary cherts have high contents of the major metallogenic elements,Their atomic percentage of Cu:Zn:Pb is similar very much between volcanic rock,hydrothermal sedimentary chert and ore.Therefore,the metallization has a direct bearing on the volcanic and hot spring activities in the Xiqiu area.The δ34S values vary from -6.5‰to 2.8‰,the δ30Si Values from-0.2‰ to 0.6‰,and the δ18O Values from 8.14‰ to 22.32‰,Lead isotopes were derived mainly from the lower crust.The ores have high contents of As,Sb,Bi,Ga,Zn,and Ba,and low Al/(Al+Fe+Mn)ratios,with Zn/(Zn+Pb)ratios approximate to unity,Therefore,the Xiqiu massive copper sulfide deposit can be ascribed to volcano-hot spring deposition.

  11. Large clusters of gold deposits and large-scale metallogene-sis in the Jiaodong Peninsula, Eastern China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Jiaodong Peninsula is the largest repository of gold in China based on the production in history. It covers less than 0.2% of China's territory, but production of gold accounts for about one fourth of the whole country. Thus, the Jiaodong Peninsula is a typical area or case of large-scale metallogenesis and a large clusters of mineral deposits in China. It is characterized by the large clusters of gold deposits in large scale, high reserve and short mineralizing stage. In this study, we suggest that the eastern boundary of the large clusters of gold deposits is as same as that of North China Block, the gold deposits are hosted by Archean metamorphic rocks or Mesozoic granites, and the age of gold mineralization is 121.6 to 122.7 Ma. Gold and related ore-forming materials are derived from multisources, i.e. Archean metamorphic rocks, granites and intermediate-mafic dikes, especially, intermediate-mafic dikes and calc-alkaline granites. The metallogenic geodynamic process is constrained by the tectonic evolution of eastern North China Block during Late Mesozoic, and it is the result of the interaction between mantle and crust as the boundary plates are playing role on the block.

  12. Mixed volcanogenic-lithogenic sources for Permian bauxite deposits in southwestern Youjiang Basin, South China, and their metallogenic significance

    Science.gov (United States)

    Yu, Wenchao; Algeo, Thomas J.; Du, Yuansheng; Zhang, Qilian; Liang, Yuping

    2016-07-01

    Bauxite deposits at the base of the Upper Permian Heshan Formation in the Youjiang Basin, South China, contain zircons with dominant age peaks at 263-262 Ma. During the Middle to Late Permian, the Youjiang Basin consisted of a number of isolated and attached carbonate platforms separated by inter-platform troughs. The bauxite deposits are limited to the isolated carbonate platform facies and are not present on attached carbonate platforms and inter-platform troughs. Discriminant plots based on the trace element composition of the zircons indicate a combination of within-plate/anorogenic and arc-related/orogenic sources. Geochemical and isotopic data suggest that the metallogenic materials of the bauxite deposit came from felsic volcanic rocks of the Emeishan Large Igneous Provence (ELIP) in South China and from the Truong Son volcanic arc located between the South China and Indochina cratons. The northwestern and southeastern parts of the Youjiang Basin received larger amounts of ELIP detritus and volcanic arc detritus, respectively. Coarser siliciclastic material in proximal attached carbonate platform and inter-platform trough settings was delivered by rivers, but finer siliciclastics that accumulated on distally located carbonate platforms in isolated deep-water areas was probably transported by wind.

  13. Appendiceal transection associated with seat belt restraint.

    Science.gov (United States)

    Go, Seung Je; Sul, Young Hoon; Ye, Jin Bong; Kim, Joong Suck

    2016-08-01

    The seat belt is designed for safety in a motor vehicle and should be worn to prevent severe injuries. But, the seat belt itself can be an injury factor in combination with deceleration forces applied to fixation points of mobile viscera. Here, we present a 23-year-man with traumatic transection of the appendix, highly mobile viscera, following seat belt injury.

  14. French experience in seat belt use.

    NARCIS (Netherlands)

    Lassarre, S. & Page, Y.

    1992-01-01

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

  15. Kuiper belts around nearby stars

    NARCIS (Netherlands)

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

    2010-01-01

    Context. The existence of dusty debris disks around a large fraction of solar type main-sequence stars, inferred from excess far-IR and submillimetre emission compared to that expected from stellar photospheres, suggests that leftover planetesimal belts analogous to the asteroid-and comet reservoirs

  16. Differential Tectonic Deformation of the Longmen Mountain Thrust Belt,Western Sichuan Basin,China

    Institute of Scientific and Technical Information of China (English)

    TANG Liangjie; YANG Keming; JIN Wenzheng; WAN Guime; L(U) Zhizhou; YU Yixin

    2009-01-01

    Field investigation and seismic section explanation showed that the Longmen Mountain Thrust Belt has obvious differential deformation:zonation,segmentation and stratification.Zonation means that, from NW to NE.the Longmen Mountain Thrust Belt can be divided into the Songpan. foreland depression.Segmentation means that it can be divided into five segments from north to South: the northern segment,the Anxian Transfer Zone,the center segment,the Guanxian Transfer Zone and the southern segment.Stratification means that the detachment layers partition the structural styles in profile.The detachment layers in the Longmen Mountain Thrust Belt can be classified into three categories:the deep-level detachment layers,including the crust-mantle system detachment layer. intracrustaI detachment layer.and Presinian system basal detachment layer;the middle.1evel detachment layers, including Cambrian-Ordovician detachment layer, Silurian detachment layer,etc.: and shallow-level detachment layers,including Upper Triassic Xujiahe Formation detachment layer and the Jurassic detachment layers.The multi-level detachment layers have a very important effect on the shaping and evolution of Longmen Mountain Thrust Belt.

  17. Seat belt sign and its significance.

    Science.gov (United States)

    Agrawal, Amit; Inamadar, Praveenkumar Ishwarappa; Subrahmanyam, Bhattara Vishweswar

    2013-07-01

    Safety belts are the most important safety system in motor vehicles and when worn intend to prevent serious injuries. However, in unusual circumstances (high velocity motor vehicle collisions) these safety measures (seat belts) can be the source and cause of serious injuries. The seat belt syndrome was first described as early by Garrett and Braunste in but the term "seat belt sign" was discussed by Doersch and Dozier. Medical personnel's involved in emergency care of trauma patients should be aware of seat belt sign and there should a higher index of suspicion to rule out underlying organ injuries.

  18. Ring current and radiation belts

    Science.gov (United States)

    Williams, D. J.

    1987-01-01

    Studies performed during 1983-1986 on the ring current, the injection boundary model, and the radiation belts are discussed. The results of these studies yielded the first observations on the composition and charge state of the ring current throughout the ring-current energy range, and strong observational support for an injection-boundary model accounting for the origins of radiation-belt particles, the ring current, and substorm particles observed at R less than about 7 earth radii. In addition, the results have demonstrated that the detection of energetic neutral atoms generated by charge-exchange interactions between the ring current and the hydrogen geocorona can provide global images of the earth's ring current and its spatial and temporal evolution.

  19. Saturation of Van Allen's belts

    CERN Document Server

    Le Bel, E

    2002-01-01

    The maximum number of electrons that can be trapped in van Allen's belts has been evaluated at CEA-DAM more precisely than that commonly used in the space community. The modelization that we have developed allows to understand the disagreement (factor 50) observed between the measured and predicted electrons flux by US satellites and theory. This saturation level allows sizing-up of the protection on a satellite in case of energetic events. (authors)

  20. Fracture patterns in the Zagros fold-and-thrust belt, Kurdistan Region of Iraq

    Science.gov (United States)

    Reif, Daniel; Decker, Kurt; Grasemann, Bernhard; Peresson, Herwig

    2012-11-01

    Fracture data have been collected in the Kurdistan Region of Iraq, which is a poorly accessible and unexplored area of the Zagros. Pre to early folding NE-SW striking extensional fractures and NW-SE striking contractive elements represent the older set affecting the exposed multilayer of the area. These latter structures are early syn-folding and followed by folding-related mesostructural assemblages, which include elements striking parallel to the axial trend of major folds (longitudinal fractures). Bedding perpendicular joints and veins, and extensional faults belonging to this second fracture set are located in the outer arc of exposed anticlines, whilst longitudinal reverse faults locate in the inner arcs. Consistently, these elements are associated with syn-folding tangential longitudinal strain. The younger two sets are related to E-W extension and NNE-SSW to N-S shortening, frequently displaying reactivation of the older sets. The last shortening event, which is described along the entire Zagros Belt, probably relates with the onset of N-S compression induced by the northward movement of the Arabian plate relative to the Eurasian Plate. In comparison between the inferred palaeostrain directions and the kinematics of recent GPS measurements, we conclude that the N-S compression and the partitioning into NW-SE trending folds and NW to N trending strike-slip faults likely remained unchanged throughout the Neogene tectonic history of the investigated area.

  1. Genesis and evolution of the Leimengou porphyry Mo deposit in West Henan Province, East Qinling-Dabie belt, China: Constraints from hydrothermal alteration, fluid inclusions and stable isotope data

    Science.gov (United States)

    Chen, Xiaodan; Ye, Huishou; Wang, Huan

    2014-01-01

    The Leimengou Mo deposit is located in the East Qinling-Dabie metallogenic Mo belt, located at the southern margin of the North China Craton. The deposit is hosted within the Mesozoic Leimengou granite porphyry pluton and at the contact between the granite and Late Archean gneisses. In light of mineral assemblage and crosscutting relationships among veinlets, the mineralization and alteration can be classified in four distinct stages: (1) a Mo-barren pre-mineralization stage of alteration characterized by massive K-feldspar alteration of the granite porphyry; (2) a K-feldspar-quartz vein stage that formed veinlets with minor molybdenite; (3) a quartz-sulfide veinlet stage, which is the main stage of mineralization; and (4) post-mineralization quartz-calcite vein stage.

  2. Intelligent seat belt reminders-do they change driver seat belt use in Europe?

    Science.gov (United States)

    Lie, Anders; Krafft, Maria; Kullgren, Anders; Tingvall, Claes

    2008-10-01

    Many modern cars have seat belt reminders (SBRs) using loud and clear sound and light signals. These systems have developed over the last few years. This study investigates how these modern systems influence the seat belt use in real-life traffic in built-up areas in some European cities. The data were collected by field observations in major cities in six European countries and in five cities around Sweden. A selection of car models having seat belt reminders (SBR) were compared to a fleet of similar car models without such reminders. A significant difference in seat belt wearing rate was found in the cars with seat belt reminders. For all observations, the total seat belt wearing rate was 97.5% +/- 0.5% in cars with SBR, while it was 85.8% +/- 0.8% in cars without. There were differences in seat belt use in the different observation locations. The lowest seat belt use was found in Brussels/Belgium with a use rate of 92.6 +/- 2.2% in cars with seat belt reminders and 69.6 +/- 3.1% in cars not fitted with reminders. The highest seat belt use was found in Paris/France where 99.8 +/- 0.4% of the drivers used the seat belt in cars with reminders and 96.9 +/-1.1% were belted in cars without reminders. Seat belt reminders fulfilling Euro NCAP's seat belt reminder protocol are increasing the seat belt use in daily traffic significantly. Around 80% (82.2% +/- 8.6%) of the drivers not putting the belt on without a seat belt reminder do so in cars equipped with an SBR that has a light signal and an associated loud and clear sound signal.

  3. The petrology of the Region between Lage and Carballo (NW Galicia, NW Spain)

    NARCIS (Netherlands)

    Geul, J.J.C.

    1964-01-01

    The area investigated comprises a 5 miles broad E-W belt mainly through the group of rocks called ”Complejo Antiguo” by professor Parga-Pondal (1956). The section runs roughly from the village of Lage on the west coast eastwards towards Carballo. The object was to detect the various relationships

  4. Synchronous and Cogged Fan Belt Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-02-01

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

  5. 1962 Satellite High Altitude Radiation Belt Database

    Science.gov (United States)

    2014-03-01

    TR-14-18 1962 Satellite High Altitude Radiation Belt Database Approved for public release; distribution is unlimited. March...the Status of the High Altitude Nuclear Explosion (HANE) Trapped Radiation Belt Database”, AFRL-VS-PS-TR- 2006-1079, Air Force Research Laboratory...Roth, B., “Blue Ribbon Panel and Support Work Assessing the Status of the High Altitude Nuclear Explosion (HANE) Trapped Radiation Belt Database

  6. Metallogenic conditions and prospecting direction for Permian manganess deposits in Northern Guizhou%黔北二叠纪锰矿成矿条件与找矿方向

    Institute of Scientific and Technical Information of China (English)

    杜小全

    2011-01-01

    黔北地区二叠纪锰矿是中国南方重要的沉积锰矿床类型,在贵州的锰矿资源中占有重要的地位.开展区内二叠纪锰矿成矿条件与找矿方向的研究与探讨,对锰矿勘查工作部署意义重大.文章拟从黔北成锰盆地的古地理环境、岩相特征、锰质来源和锰矿赋存规律4个方面,分析区内二叠纪锰矿成矿条件,在此基础上提出找矿方向并对资源前景预测.%The Permian manganese deposits in Northern Guizhou, a main aedimentary type manganese deposit in Southem Chi na, play an important role in manganese mineral resources of Guizhou. It is meaningful to study regional metallogenic condition of Per mian manganese deposit for exploration. In this paper, the author analyzed metallogenic conditions of Permian manganese deposits from four aspects, i. e. , the paleo - geographical environment of the basin in which manganese deposit developed, lithofacie8 characteris ticts, source of mangancse, and hosting regularity of manganese deposits, and then proposed the prospecting direction and forecasting potential resource.

  7. Overall hydrochemical characterization of the Iberian Pyrite Belt. Main acid mine drainage-generating sources (Huelva, SW Spain)

    Science.gov (United States)

    Grande, J. A.; de la Torre, M. L.; Cerón, J. C.; Beltrán, R.; Gómez, T.

    2010-09-01

    SummaryAMD is an anthropogenic process caused by sulfide mineralization and the increase in the contact surface due to mining activity and grain-size reduction. In Spain, the contamination comes from the metal sulfide mines in the Iberian Pyrite Belt (IPB). Spreading over an area 230 km long and approximately 50 km wide, it is one of the largest metallogenic regions in the world, with massive sulfide reserves of about 1700 Mt. In the present study we will characterize AMD contamination processes in the IPB, especially by As, by identifying the sources responsible for these processes (active mines and effluents from mines and slag heaps) in the basins of the Tinto and Odiel rivers. It is also the aim of this study to discover the mineral associations of the deposits. The study of the AMD process generating source is complemented with hydrochemical characterization of the effluents produced, which will be carried out by means of sample-taking and subsequent chemical analysis and statistical treatment (cluster analysis). Characteristics in common with samples taken in other AMD-affected watercourses are observed in the seven zones defined in the study area. With respect to the samples studied, obvious differences can also be found. These differences are inherent to the mineral associations, watershed and distance to the generating source and, ultimately, to the affected area, and the type, intensity and duration of the mine treatment process developed in the acid-producing area.

  8. 甘肃龙尾沟斑岩型铜(钨)矿床成矿特征及形成环境%Geological Characteristics and Metallogenic Environment of the Longweigou Porphyry Copper(tungsten) Deposit,Gansu

    Institute of Scientific and Technical Information of China (English)

    贾群子; 马云海; 全守村; 王建军; 肖朝阳; 李金超

    2012-01-01

    龙尾沟铜(钨)矿床是祁连山地区新近发现的一处斑岩型矿床,其评价及研究对祁连山地区铜矿勘查具有重要的指导和借鉴作用.本文通过对含矿斑岩年代学及地球化学、矿体产出特征及矿石物质组成、围岩蚀变等进行了系统研究,结果表明,花岗闪长斑岩形成年龄为358.7 Ma;矿体呈似层状、透镜状和脉状产出,主要产于高钾碱性系列斑岩体内,并受近南北向构造控制;矿石矿物主要为黄铜矿、黄铁矿、磁黄铁矿、白钨矿,呈细脉一浸染状、浸染状产出;矿化以富铜、钨、金贫钼为特征;与成矿关系密切的围岩蚀变主要为绢英岩化,次为钾硅酸盐化和硅化;矿床成矿时代为海西早期,形成于陆内造山伸展环境.从成矿背景分析认为祁连山地区陆内造山环境所形成的斑岩型铜矿具有良好的找矿前景.%The Longweigou porphyry copper( tungsten) deposit, a newly found deposit, lies in the Oulongbuluke uplift belt of the Qilian orogenic belt. The evaluation and research of the Longweigou copperCtungsten) ore deposit will present important guidance and reference for copper exploration in the Qilian Mountain area. The chronology and the geochemistry of the ore-bearing porphyry deposit were studied and the occurrence features of the deposit, the components of gold mineral and the alteration of the wall rock were investigated. Results showed that the formation age of the granodiorite porphyry is 358. 7Ma; and that the ore-body, which has occurrences of stratiform or lenticular or vein, occurs mainly in the high potassium alkali series porphyry and is controlled by NS structures; and that chalcopyrite, pyrite, pyrrhotite, and scheelite are main ore minerals, which have veinlet-disseminated and disseminated structures; and that mineralization is characterized by enriching copper, tungsten and gold and depleting molybdenum; and that the mineralization related wall-rock alterations are

  9. Formation of Kuiper Belt Binaries

    CERN Document Server

    Goldreich, P; Sari, R; Goldreich, Peter; Lithwick, Yoram; Sari, Re'em

    2002-01-01

    It appears that at least several percent of large Kuiper belt objects are members of wide binaries. Physical collisions are too infrequent to account for their formation. Collisionless gravitational interactions are more promising. These provide two channels for binary formation. In each, the initial step is the formation of a transient binary when two large bodies penetrate each other's Hill spheres. Stabilization of a transient binary requires that it lose energy. Either dynamical friction due to small bodies or the scattering of a third large body can be responsible. Our estimates favor the former, albeit by a small margin. We predict that most objects of size comparable to those currently observed in the Kuiper belt are members of multiple systems. More specifically, we derive the probability that a large body is a member of a binary with semi-major axis of order a. The probability depends upon sigma, the total surface density, Sigma, the surface density of large bodies having radius R, and theta=10^-4, t...

  10. Jupiter's radiation belts and atmosphere

    Science.gov (United States)

    De Pater, I.; Dames, H. A. C.

    1979-01-01

    Maps and stripscans of the radio emission from Jupiter were made during the Pioneer 10 flyby in December 1973 at wavelengths of 6 cm, 21 cm, and 50 cm using the Westerbork telescope in the Netherlands. With this instrument the disk of the planet was resolved at 6 and 21 cm. The pictures are averaged over 15 deg of Jovian longitude. At 21 cm the stripscans clearly show the existence of a 'hot region' in the radiation belts at a System III longitude (1965.0) of 255 + or - 10 deg. Its flux is about 9% of the total nonthermal flux, and it has a volume emissivity enhanced by a factor of about 1.6 with respect to the general radiation belts. The temperature of the thermal disk at 21 cm appears to be 290 + or - 20 K. This is likely due to a high ammonia mixing ratio in the atmosphere, a factor of 4-5 larger than the expected solar value of 0.00015.

  11. Beyond the Kuiper Belt Edge

    Science.gov (United States)

    Sheppard, Scott

    2013-01-01

    Of the thousands of known objects beyond Neptune, only one has a perihelion significantly beyond 50 AU, Sedna at 75 AU. Most Kuiper Belt surveys to date either did not go faint enough, did not have the required long cadence to detect very slow moving objects or covered too small of an area of sky to efficiently detect objects beyond 50 AU. The dynamical and physical properties of objects in this region offer key constraints on the formation and evolution of our solar system. In order to probe the Sedna like population of objects with moderate radii (100 km) we are conducting a deep wide-field outer solar system survey. This survey will allow us to determine if the objects beyond 50 AU are fainter than expected, if there is truly a dearth of objects, or if the Kuiper Belt continues again after some sizable gap possibly caused by a planet sized object. We will be able to examine the origin of Sedna and determine if it is unique (as once believed for Pluto) or one of a new class of object. We request one night in 2013B to recover a very interesting object that we discovered at Subaru in July 2012 and complete the sky coverage needed to constrain the Sedna-like population. This one night was awarded to us in 2012B but lost because of instrument problems.

  12. Bimodal volcanism in a tectonic transfer zone: Evidence for tectonically controlled magmatism in the southern Central Andes, NW Argentina

    Science.gov (United States)

    Petrinovic, I. A.; Riller, U.; Brod, J. A.; Alvarado, G.; Arnosio, M.

    2006-04-01

    This field-based and analytical laboratory study focuses on the genetic relationship between bimodal volcanic centres and fault types of an important tectonic transfer zone in the southern Central Andes, the NW-SE striking Calama-Olacapato-Toro (COT) volcanic belt. More specifically, tectono-magmatic relationships are examined for the 0.55 Ma Tocomar, the 0.78 Ma San Jerónimo and the 0.45 Ma Negro de Chorrillos volcanic centres in the Tocomar area (66°30 W-24°15 S). Structures of the COT volcanic belt, notably NW-SE striking strike-slip faults and NE-SW trending normal faults, accommodated differential shortening between major N-S striking thrust faults on the Puna Plateau. We present evidence that bimodal volcanism was contemporaneous with activity of these fault types in the COT volcanic belt, whereby eruption and composition of the volcanic rocks in the Tocomar and San Jerónimo-Negro de Chorrillos areas appear to have been controlled by the kinematics of individual faults. More specifically, rhyolitic centres such as the Tocomar are associated with normal faults, whereas shoshonitic-andesitic monogenetic volcanoes, e.g., the San Jerónimo and Negro de Chorrillos centres, formed at strike-slip dominated faults. Thus, the eruption of higher viscous rhyolite magmas appears to have been facilitated in tectonic settings characterized by horizontal dilation whereas ascent and effusive volcanic activity of less viscous and hot basaltic andesites to shoshonites were controlled by subvertical strike-slip faults. While the Tocomar rhyolites are interpreted to be derived from an anatectic crustal source, geochemical characteristics of the San Jerónimo and Negro de Chorrillos shoshonitic andesites are in agreement with a deeper source. This suggests that the composition of erupted volcanic rocks as well as their spatial distribution in the Tocomar area is controlled by the activity of specific fault types. Such volcano-tectonic relationships are also evident from older

  13. Parameters affecting seat belt use in Greece.

    Science.gov (United States)

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

    2011-09-01

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

  14. Intelligent Belt Conveyor Monitoring and Control

    NARCIS (Netherlands)

    Pang, Y.

    2010-01-01

    Belt conveyors have been used worldwide in continuous material transport for about 250 years. Traditional inspection and monitoring of large-scale belt conveyors focus on individual critical components and response to catastrophic system failures. To prevent operational problems caused by the lack

  15. The Administrator's "Handy Dandy" Tool Belt

    Science.gov (United States)

    Anderson, Terry

    2012-01-01

    Every good leader needs a tool belt. Throughout the author's years of building early childhood programs, she has acquired a number of tools for her personal belt. These tools have helped her sharpen her skills in supporting teachers and staff, connecting with families, and educating children. This article focuses on those leadership skills that…

  16. Intelligent Belt Conveyor Monitoring and Control

    NARCIS (Netherlands)

    Pang, Y.

    2010-01-01

    Belt conveyors have been used worldwide in continuous material transport for about 250 years. Traditional inspection and monitoring of large-scale belt conveyors focus on individual critical components and response to catastrophic system failures. To prevent operational problems caused by the lack o

  17. Biomechanics of seat belt restraint system.

    Science.gov (United States)

    Sances, Anthony; Kumaresan, Srirangam; Herbst, Brian; Meyer, Steve; Hock, Davis

    2004-01-01

    Seat belt system restrains and protects occupants in motor vehicle crashes and any slack in seat belt system induces additional loading on occupant. Signs of belt loading are more obvious in high-speed frontal collisions with heavy occupants. However subtle changes may occur at low speeds or with low forces from occupants during rollovers. In certain cases, the seat belt webbing is twisted and loaded by the occupant. The loading of webbing induces an observable fold/crimp on the seat belt. The purpose of the study is to biomechanically evaluate the force required to produce such marks using an anthropometric physical test dummy. Two tests were conducted to determine the amount of force required to put an observable fold/crimp in a shoulder belt. A head form designed by Voight Hodgson was used to represent the neck which interacted with the belt. The force was applied with a pneumatic pull ram (central hydraulic 89182 N) and the force was measured with a 44,000 N transducer load cell (DSM-10K). Results indicate that the force of over 1,000 N produced a fold or crimp in the belt.

  18. Seat Belts on School Buses: Some Considerations.

    Science.gov (United States)

    Soule, David

    1982-01-01

    A representative of the National Highway Traffic Safety Administration weighs advantages and discusses issues associated with installing seat belts in school buses. Federal regulations and research findings are considered. A list of guideline questions for school districts planning to install seat belts is included. (PP)

  19. Seat belt use in cars with air bags.

    Science.gov (United States)

    Williams, A F; Wells, J K; Lund, A K

    1990-12-01

    Seat belt use was observed in 1,628 cars with air bags and manual belts and 34,223 cars with manual seat belts only. Sixty-six percent of drivers in cars with air bags wore seat belts compared to 63 percent of drivers in cars with manual belts only. The study found no evidence for the speculation that drivers with air bags will reduce their seat belt use because they believe an air bag alone provides sufficient protection.

  20. Radiation belt dynamics during solar minimum

    Energy Technology Data Exchange (ETDEWEB)

    Gussenhoven, M.S.; Mullen, E.G. (Geophysics Lab., Air Force Systems Command, Hanscom AFB, MA (US)); Holeman, E. (Physics Dept., Boston College, Chestnut Hill, MA (US))

    1989-12-01

    Two types of temporal variation in the radiation belts are studied using low altitude data taken onboard the DMSP F7 satellite: those associated with the solar cycle and those associated with large magnetic storm effects. Over a three-year period from 1984 to 1987 and encompassing solar minimum, the protons in the heart of the inner belt increased at a rate of approximately 6% per year. Over the same period, outer zone electron enhancements declined both in number and peak intensity. During the large magnetic storm of February 1986, following the period of peak ring current intensity, a second proton belt with energies up to 50 MeV was found at magnetic latitudes between 45{degrees} and 55{degrees}. The belt lasted for more than 100 days. The slot region between the inner and outer electron belts collapsed by the merging of the two populations and did not reform for 40 days.

  1. Infection by Paramphistomidae trematodes in cattle from two agricultural regions in NW Uruguay and NW Spain.

    Science.gov (United States)

    Sanchís, J; Sánchez-Andrade, R; Macchi, M I; Piñeiro, P; Suárez, J L; Cazapal-Monteiro, C; Maldini, G; Venzal, J M; Paz-Silva, A; Arias, M S

    2013-01-16

    The analysis of infection by Paramphistomidae trematodes was conducted in two agricultural regions with different knowledge on this parasitosis. Faecal and blood samples were collected from 374 cattle in Salto (NW Uruguay) where there is a lack of information about paramphistomosis. A total of 429 cattle from Galicia (NW Spain), an area with previous records of infection by gastric flukes, were sampled. Diagnostics of trematodosis was developed by using a copromicroscopic probe and an ELISA with excretory/secretory antigens collected from adult Calicophoron daubneyi (Paramphistomidae) specimens. Results were evaluated according intrinsic and extrinsic factors. In the Uruguay, the percentage of cattle passing Paramphistomidae-eggs by faeces was 7% (95% Confidence Interval 5, 10). A significantly higher prevalence of paramphistomosis in the Hereford × Angus cattle (OR=3.5) was recorded, as observed for the oldest ruminants (>3.5 years). An overall seroprevalence of 29% (25, 34) was obtained by ELISA, with the highest values in the Friesians (OR=3), the youngest bovines (Uruguay, especially by improving their management to avoid exposure to the gastric trematode. Further studies are in progress for identifying the species of Paramphistomidae affecting ruminants in Uruguay.

  2. NW-MILO Acoustic Data Collection

    Energy Technology Data Exchange (ETDEWEB)

    Matzner, Shari; Myers, Joshua R.; Maxwell, Adam R.; Jones, Mark E.

    2010-02-17

    There is an enduring requirement to improve our ability to detect potential threats and discriminate these from the legitimate commercial and recreational activity ongoing in the nearshore/littoral portion of the maritime domain. The Northwest Maritime Information and Littoral Operations (NW-MILO) Program at PNNL’s Coastal Security Institute in Sequim, Washington is establishing a methodology to detect and classify these threats - in part through developing a better understanding of acoustic signatures in a near-shore environment. The purpose of the acoustic data collection described here is to investigate the acoustic signatures of small vessels. The data is being recorded continuously, 24 hours a day, along with radar track data and imagery. The recording began in August 2008, and to date the data contains tens of thousands of signals from small vessels recorded in a variety of environmental conditions. The quantity and variety of this data collection, with the supporting imagery and radar track data, makes it particularly useful for the development of robust acoustic signature models and advanced algorithms for signal classification and information extraction. The underwater acoustic sensing system is part of a multi-modal sensing system that is operating near the mouth of Sequim Bay. Sequim Bay opens onto the Straight of Juan de Fuca, which contains part of the border between the U.S. and Canada. Table 1 lists the specific components used for the NW-MILO system. The acoustic sensor is a hydrophone permanently deployed at a mean depth of about 3 meters. In addition to a hydrophone, the other sensors in the system are a marine radar, an electro-optical (EO) camera and an infra-red (IR) camera. The radar is integrated with a vessel tracking system (VTS) that provides position, speed and heading information. The data from all the sensors is recorded and saved to a central server. The data has been validated in terms of its usability for characterizing the

  3. Spatial evolution of Zagros collision zone in Kurdistan - NW Iran, constraints for Arabia-Eurasia oblique convergence

    Science.gov (United States)

    Sadeghi, S.; Yassaghi, A.

    2015-09-01

    Stratigraphy, detailed structural mapping and crustal scale cross section of the NW Zagros collision zone evolved during convergence of the Arabian and Eurasian plates were conducted to constrain the spatial evolution of the belt oblique convergence since Late Cretaceous. Zagros orogeny in NW Iran consists of the Sanandaj-Sirjan, Gaveh Rud and ophiolite zones as internal, and Bisotoun, Radiolarite and High Zagros zones as external parts. The Main Zagros Thrust is known as major structures of the Zagros suture zone. Two stages of deformation are recognized in the external parts of Zagros. In the early stage, presence of dextrally deformed domains beside the reversely deformed domains in the Radiolarite zone as well as dextral-reverse faults in both Bisotoun and Radiolarite zones demonstrates partitioning of the dextral transpression. In the late stage, southeastward propagation of the Zagros orogeny towards its foreland resulted in synchronous development of orogen-parallel strike-slip and pure thrust faults. It is proposed that the first stage related to the late Cretaceous oblique obduction, and the second stage is resulted from Cenozoic collision. Cenozoic orogen-parallel strike-slip component of Zagros oblique faulting is not confined to the Zagros suture zone (Main Recent) but also occurred in the more external part (Marekhil-Ravansar fault system). Thus, it is proposed that oblique convergence of Arabia-Eurasia plates occurred in Zagros collision zone since the Late Cretaceous.

  4. Using SHRIMP zircon dating to unravel tectonothermal events in arc environments. The early Palaeozoic arc of NW Iberia revisited

    Science.gov (United States)

    Abati, J.; Castineiras, P.G.; Arenas, R.; Fernandez-Suarez, J.; Barreiro, J.G.; Wooden, J.L.

    2007-01-01

    Dating of zircon cores and rims from granulites developed in a shear zone provides insights into the complex relationship between magmatism and metamorphism in the deep roots of arc environments. The granulites belong to the uppermost allochthonous terrane of the NW Iberian Massif, which forms part of a Cambro-Ordovician magmatic arc developed in the peri-Gondwanan realm. The obtained zircon ages confirm that voluminous calc-alkaline magmatism peaked around 500Ma and was shortly followed by granulite facies metamorphism accompanied by deformation at c. 480Ma, giving a time framework for crustal heating, regional metamorphism, deformation and partial melting, the main processes that control the tectonothermal evolution of arc systems. Traces of this arc can be discontinuously followed in different massifs throughout the European Variscan Belt, and we propose that the uppermost allochthonous units of the NW Iberian Massif, together with the related terranes in Europe, constitute an independent and coherent terrane that drifted away from northern Gondwana prior to the Variscan collisional orogenesis. ?? 2007 Blackwell Publishing Ltd.

  5. Geochronology, geochemistry and metallogenic implications of the Lamasu intrusion in western Tianshan, NW China%西天山喇嘛苏岩体年代学、地球化学及成矿意义

    Institute of Scientific and Technical Information of China (English)

    解洪晶; 武广; 朱明田; 晋建平; 钟伟; 刘军; 糜梅

    2013-01-01

    The zircon U-Pb geochronology , major and trace elements and Sr-Nd isotopes determination of the Lamasu intrusion in western Chinese Tianshan were conducted to understand its petrogenesis and geodynamic setting. The Lamasu intrusion is mainly composed of quartz monzodiorite,granodiorite porphyry and tonalite porphyry. Among them the quartz monzodiorite was formed in 394. 8 + 4. 9 Ma, while the granodiorite porphyry and tonalite porphyry were intruded in 380, 9 + 3. 9 Ma. The rocks display the adakitic affinity and show a calc-alkaline and high-K calc-alkaline differentiation trend. They display REE patterns characterized by relative enrichment of LREE ((La/Yb)N: 3. 55 - 15. 52) with slightly negative or positive Eu anomalies (δEu: 0. 53 - 1. 12). They have high Sr ((322 - 808) × 10-6) and low Y contents ((12. 90 - 18. 86) ×10-6) and also enriched in LILE but depleted in HFSE with negative Nb, Ta and Ti anomalies. Initial Sr-Nd isotopic compositions are εNd(t) = -4. 29 to 0. 75 and Isr = 0. 706052 to 0. 708263. The Nd model ages vary from 1. 03 to 1. 46 Ga. The Pb isotopic ratios of granodiorite porphyry and tonalite porphyry are 206Pb/204Pb=18. 500 -19. 044,207Pb/204 Pb= 15. 575 - 15. 626,208Pb/204 Pb= 38. 443 - 38. 864, while the quartz monzodiorite are 206Pb/204Pb=18. 694 - 18. 711,207Pb/204Pb=15. 622 - 15. 630,208Pb/204 Pb = 38. 648 - 38. 660. All these geochemical data demonstrate that the Lamasu intrusion is likely derived from the partial melting of oceanic crust, with the subsequent melts interacted during their uplift with the overlying mantle wedge metasomatized by the subducted sediments and subordinately contaminated by ancient crust. The Lamasu intrusion was emplaced in a continental arc setting during the southward subduction of the Junggar Remnant Ocean Basin in the Late Devonian and are closely related with Cu (Au) mineralization of that region.%文中主要对西天山喇嘛苏岩体进行SHRIMP锆石U-Pb年龄、主微量及Sr-Nd-Pb同位素测定,阐明岩体成因及形成构造背景.喇嘛苏岩体主要由石英二长闪长岩、花岗闪长斑岩和英云闪长斑岩组成.其中,石英二长闪长岩形成于(394.8±4.9)Ma,花岗闪长斑岩和英云闪长斑岩形成于(380.9±3.9)Ma,略晚于石英二长闪长岩.岩体具有埃达克质岩的特征,且显示从钙碱性向高钾钙碱性演化的趋势,稀土元素配分曲线显示相对富集轻稀土((La/Yb)N:3.55~15.52)及中等的负或正Eu异常(δEu:0.53~1.12).岩体具有较高的Sr含量((322~808)×10-6)和较低的Y含量((12.90~18.86)×10-6).微量元素特征显示岩体富集LILE亏损HFSE,并具有Nb、Ta和Ti负异常.岩体初始Sr-Nd同位素组成为εNd(t)=-4.29~+0.75和Isr=0.706 052~0.708 263,Nd模式年龄为1.03~1.46Ga.花岗闪长斑岩和英云闪长斑岩的铅同位素特征为206 Pb/204 Pb=18.500~19.044,207Pb/204 Pb=15.575~15.626,208Pb/204 Pb=38.443~38.864;石英二长闪长岩为206 Pb/204 Pb=18.694~18.711,207 Pb/204 Pb=15.622~15.630,208Pb/204Pb=38.648~38.660.所有地球化学特征显示喇嘛苏岩体是俯冲洋壳部分熔融形成的熔体,上升过程中与受俯冲带沉积物交代的地幔楔相互作用,且有少量古老地壳的混染而形成.岩体形成于晚泥盆世准噶尔残余洋盆向伊犁—中天山地块俯冲的大陆弧背景,与该区Cu(Au)矿化有较密切的联系.

  6. Seat belt use law in developing countries

    Institute of Scientific and Technical Information of China (English)

    SangWanLee

    1999-01-01

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

  7. Mineralogy, occurrence of mineralization and temperature-pressure conditions of the Agh-Daragh polymetallic deposit in the Ahar-Arasbaran metallogenic area

    Directory of Open Access Journals (Sweden)

    Heydar Asgharzadeh Asl

    2017-07-01

    Full Text Available Introduction The Ahar-Arasbaran metallogenic area (Qara Dagh zone is located in the northwest of Iran and the western part of the Mazandaran Sea. At the base of the structural classification from Nabavi (1976, this area is situated in the Alborz-Azerbijan magmatic belt. Sheviar Dagh (Ahar batholite intrusive suite, subvolcanic and volcanic accompanied rocks with east-west trending and 30 km long serves as the main Eocene-Oligocene magmatic event in the north of the Ahar province. Considering geochemistry, this assemblage includes two shoshonitic and calc-alkaline to high-K calc-alkaline series which are the shoshonitic series in the central part and the calc-alkaline series outcrop in the western and eastern part (Aghazadeh, 2009. Textural characteristic, mineral chemistry and fluid inclusion studies were carried out at the tree part of the Agh-Daragh prospecting area. Material and methods A total of 50 samples were collected from the host rocks (including 4 trench and 250 m, ore deposit and altered rocks. Ten altered samples were analyzed for their mineral recognition by X-ray diffraction in the Iran Mineral Process and Research Center (IMPRC. Electron microprobe analyses (EMPA and backscattered electron (BSE images of minerals were obtained using a Cameca SX100 electron microprobe in the Iran Mineral Process and Research Center (IMPRC. An accelerating voltage of 15 to 25 kV and beam current of 20 mA was used for all analyses. Typical spot sizes ranged from 2 to 5 μm. A total of 5 double-polish thin sections representative of quartz samples were selected from mineralized veins after petrographic and field studies. Fluid inclusion microthermometry was conducted using a Linkam THMS600 heating–freezing stage (-190°C to +600°C mounted on a ZEISS Axioplan2 microscope in the fluid inclusion laboratory of the school of Earth Sciences of the Kharazmi University. The heating rate was 5–10 °C/min at higher temperatures (>100°C, with a

  8. Petrography, Geochemistry and Petrogenesis of Volcanic Rocks, NW Ghonabad, Iran

    Directory of Open Access Journals (Sweden)

    Sedigheh Zirjanizadeh

    2016-07-01

    Full Text Available Introduction The study area is located in NW Gonabad, Razavi Khorasan Province, northern Lut block and eastern Iran north of the Lut Block. Magmatism in NW Gonabad produced plutonic and volcanic rock associations with varying geochemical compositions. These rocks are related to the Cenozoic magmatic rocks in Iran and belong to the Lut Block volcanic–plutonic belt. In this study, petrogenesis of volcanic units in northwest Gonabad was investigated. The volcanic rocks are andesites/trachyandesites, rhyolites, dacites/ rhyodacites and pyroclastics.These rocks show porphyritic, trachytic and embayed textures in phenocrysts with plagioclase, sanidine and quartz (most notably in dacite and rhyolite, hornblende and rare biotite. The most important alteration zones are propylitic, silicification and argillic.Four kaolinite- bearing clay deposits have been located in areas affectedby hydrothermal alteration of Eocene rhyolite, dacite and rhyodacite. Analytical techniques Five samples were analyzed for major elements by wavelength dispersive X-ray fluorescence (XRF and six samples were analyzed for trace elements using inductively coupled plasma-mass spectrometry (ICP-MS in the Acme Laboratories, Vancouver (Canada.Sr and Nd isotopic compositions were determined for four whole-rock samples at the Laboratório de GeologiaIsotópica da Universidade de Aveiro, Portugal. Results Petrography. The rocks in this area are consist of trachyte, andesite/ trachyandesite, dacite/ rhyodacite, principally as ignimbrites and soft tuff. The textures of phenocrysts are mainly porphyritic, glomerophyric, trachytic and embayed textures in plagioclase, hornblende and biotite. The groundmasses consist of plagioclase and fine-grainedcrystals of hornblende. Plagioclase phenocrysts and microlitesare by far the most abundant textures in andesite - trachyandesites (>25% and in size from 0.01 to 0.1mm. Euhedral to subhedral hornblende phenocrysts areabundant (3-5%and 0.1 to 0

  9. 辽东半岛滨海砂金矿成矿规律%Metallogenic Regularity of the Coastal Gulch-gold Deposit in Liaodong Peninsula

    Institute of Scientific and Technical Information of China (English)

    刘长纯; 姚志宏; 孙鹏慧

    2016-01-01

    Liaodong peninsula coastal gulch-gold mine is not development,less resources,in order to provide the theoretical reference for the prospecting work of coastal gulch-gold deposit in Liaodong pen-insula,the metallogenic conditions of the coastal gulch-gold deposit are analyzed,the results show that:①the new archean strata and ancient proterozoic strata are developed in Liaodong peninsula,intrusive rocks and native gold deposits (points)with the characteristics of more material source and multi-stage forma-tion;②the climatic conditions along the Yellow sea coast are conducive to weathering and erosion,with more rainfall and large rive transport capacity,a large number of ore-forming materials are transported for the gulch-gold deposit;③the favorable metallogenic environment for the formation of coastal gulch-gold deposits is provided by the abundant land physiognomy,sea bottom physiognomy,coastal types physiogno-my and Quaternary type physiognomy with alluvial-diluvial causes;④the new tectonic movement is mainly for overall lift long up,which caused the the peninsula suffered the strong erosion in the entire Quaterna-ry,so,the sufficient material source for the gulch-gold deposit is provided.Based on the above analysis re-sults,the metallogenic material source,metallogemnic dynamic and metallogenic environment are dis-cussed from the aspects of ore-forming material supply conditions,climate and hydrodynamic conditions and sedimentary environment.The above study results can provide some reference for the prospecting work of coastal gulch-gold deposit in Liaodong peninsula.%辽东半岛滨海砂金矿不发育、资源量少,为进一步加强寻找滨海砂金矿,对滨海砂金矿的成矿条件进行了分析,结果表明:①区内具有新太古、古中元古代地层,侵入岩和原生金矿床(点)具有多物质来源和形成的多阶段性;②半岛黄海沿岸的气候条件有利于风化剥蚀作用的进行,伴随着降雨较多

  10. PGE patterns of ores of Dajing Cu-polymetallic deposit in Linxi County, Inner Mongolia: Indicator to source of metallogenic elements

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle lherzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

  11. Drive Alive: Teen Seat Belt Survey Program

    Directory of Open Access Journals (Sweden)

    Loftin, Laurel

    2010-08-01

    Full Text Available Objective: To increase teen seat belt use among drivers at a rural high school by implementing the Drive Alive Pilot Program (DAPP, a theory-driven intervention built on highway safety best practices.Methods: The first component of the program was 20 observational teen seat belt surveys conducted by volunteer students in a high school parking lot over a 38-month period before and after the month-long intervention. The survey results were published in the newspaper. The second component was the use of incentives, such as gift cards, to promote teen seat belt use. The third component involved disincentives, such as increased police patrol and school policies. The fourth component was a programmatic intervention that focused on education and media coverage of the DAPP program.Results: Eleven pre-intervention surveys and nine post-intervention surveys were conducted before and after the intervention. The pre- and post-intervention seat belt usage showed significant differences (p<0.0001. The average pre-intervention seat belt usage rate was 51.2%, while the average post-intervention rate was 74.5%. This represents a percentage point increase of 23.3 in seat belt use after the DAPP intervention.Conclusion: Based on seat belt observational surveys, the DAPP was effective in increasing seat belt use among rural high school teenagers. Utilizing a theory-based program that builds on existing best practices can increase the observed seat belt usage among rural high school students. [West J Emerg Med. 2010; 11(3: 280-283.

  12. Time distribution of the main Brazilian mineral deposits. 2: metallogenic epochs; Distribuicao no tempo geologico dos principais depositos minerais brasileiros. 2: epocas metalogeneticas

    Energy Technology Data Exchange (ETDEWEB)

    Biondi, Joao C. [Parana Univ., Curitiba, PR (Brazil). Dept. de Geologia]. E-mail: jcbiondi@setuva.geologia.ufpr.br

    1999-12-01

    The metallogenic epochs of the main mineral deposit groups were defined with base on the ore's of the 194 main Brazilian mineral deposits. Mineral deposits are rare on epochs that: precede the beginning of juvenile accretion peak periods, and/or of cooling of rocks formed during each of the main brazilian thermo-tectonic events. Deposits are more frequent on epochs that are coincident or immediately younger than these peak periods. The most important metallogenic epoch, with about 30% of the selected deposits, is between 50 Ma and the Recent, and corresponds to the formation of supergenic and/or residual and placer deposits. Brazilian's volcanogenic (VHMS), Mississippi Valley (MTV) and mesothermal gold-lode deposits have discordant ages as compared with their equivalents in other countries, while deposits believed to be SEDEX have concordant ages. With the exception of Urucum, the primary iron and manganese ores of brazilian deposits are Archean. Primary tin deposits from Amazonas, Amapa and Goias State cluster between 1500 and 2300 Ma. Tin deposits from Rondonia and Mato Grosso are more recent and most formed between 1000 and 1600 Ma, in sequence with the other groups of tin deposits. Uranium deposits vary on genetic model and ages, due to the mobility of the element in all geologic environments. Most part of Brazilian deposits of phosphate, titanium, niobium, Rare Earths, diamond in kimberlites and of amethyst formed during the Mesozoic, and arte genetically related to the alkaline and basaltic magmatism that affected the brazilian territory in this period. Gemstone (tourmaline and aquamarine), talc and magnesite deposits are more frequent in the Brasiliano period. Gipsite, silvite and barite occur in Senonian to Aptian evaporites. (author)

  13. Computer-aided design of conveyor belts

    Energy Technology Data Exchange (ETDEWEB)

    Karolewski, B.; Pytel, J.

    1984-01-01

    Possibilities are discussed for using mathematical models of belt conveyors for development of computer-aided design of conveyors for coal mining. Examples of optimization tasks and methods for their solution using computerized simulation are analyzed. The analysis is illustrated by an algorithm used to design a starter for the drive system of a belt conveyor. Electromagnetic moment and starting current are used as optimization criteria. A simplified model of a belt conveyor is used. The model consists of an equation of motion with variable braking moment and variable moment of inertia. 3 references.

  14. Collisional evolution of the early asteroid belt

    Science.gov (United States)

    Gil-Hutton, Ricardo; Brunini, Adrián

    1999-04-01

    We present numerical results obtained by a simulation of the collisional process between asteroids and scattered comets from the Uranus-Neptune zone. This mechanism allows the use of single exponent incremental size distributions for the initial belt reaching a final distribution that matches the observed population very well. Since the cometary bombardment was extremely efficient removing mass from the primordial asteroid belt in a very short time, we always obtained belts with total masses less than 0.001 M ⊕ after ≈ 2×10 7 yrs. This result allows processes with an important initial mass preserving Vestas basaltic crust.

  15. 陕西神河钡矿床矿物流体包裹体特征与成矿物理化学条件%Fluid inclusion characteristics and metallogenic physicochemical conditions of Shenhe barium deposit, Shaanxi Province

    Institute of Scientific and Technical Information of China (English)

    吴胜华; 刘家军; 柳振江; 翟德高; 邢永亮

    2011-01-01

    The Shenhe barium deposit in Shaanxi Province occurs in the northern ore zone of the early Paleozoic South Qinling barium metallogenic belt. Barite and witherite are main ore minerals. Microthermometric analyses show that the homogenization temperature ranges of the fluid inclusions in barite, witherite and barytocalcite are 108 -205°C(with main peak at 130~170°C), 118-274°C (with main peak at 150-210°C) and 146~227°C,respectively, and the salinity ranges of the fluid inclusions in the barite, witherite and barytocalcite zv(NaCleq) are 0.53% ~ 9.86% , 0.18% ~ 8.95 % and 4.03% ~ 7.31 % , respectively. Laser Raman analyses show that the gas and liquid phase composition of the fluid inclusions in barite is H2O, the gas phase compositions of the fluid inclusions in witherite are composed of CO2, N2, H2S and CH4, the gas phase compositions of the fluid inclusions in barytocalcite include CO2 and N2, and the gas phase compositions of the fluid inclusions in quartz consist of CO2, N2, H2S and CH4. It is concluded that metallogenic conditions of various kinds of barium minerals were different. The formation of witherite was possibly associated with thermochemical sulfate reduction, which consumed lots of organic gases and SG4 in hydrothermal fluids and also inhibited the formation of barite when witherite was formed. The authors thus hold that thermochemical sulfate reduction transferred carbon from organic gases into witherite. Relatively high fluid temperatures, the existence of CO2, fairly high Ba + concentrations, and the environment of high HS concentrations and rapid diffusion of H2S in ore-forming fluids before thermochemical sulfate reduction constituted important factors for witherite formation.%陕西神河钡矿床位于南秦岭钡成矿带的北矿带,重晶石和毒重石为主要的矿石组成.显微测温分析表明,重晶石、毒重石和钡解石内流体包裹体的均一温度范围分别为108~205℃(峰值130~170℃)、118~274

  16. Palynological evidence for climatic and oceanic variability off NW Africa during the late Holocene

    Science.gov (United States)

    Bouimetarhan, Ilham; Dupont, Lydie; Schefuß, Enno; Mollenhauer, Gesine; Mulitza, Stefan; Zonneveld, Karin

    2009-09-01

    Pollen and organic-walled dinoflagellate cyst assemblages from core GeoB 9503-5 retrieved from the mud-belt (˜ 50 m water depth) off the Senegal River mouth have been analyzed to reconstruct short-term palaeoceanographic and palaeoenvironmental changes in subtropical NW Africa during the time interval from ca. 4200 to 1200 cal yr BP. Our study emphasizes significant coeval changes in continental and oceanic environments in and off Senegal and shows that initial dry conditions were followed by a strong and rapid increase in humidity between ca. 2900 and 2500 cal yr BP. After ca. 2500 cal yr BP, the environment slowly became drier again as indicated by slight increases in Sahelian savannah and desert elements in the pollen record. Around ca. 2200 cal yr BP, this relatively dry period ended with periodic pulses of high terrigenous contributions and strong fluctuations in fern spore and river plume dinoflagellate cyst percentages as well as in the fluxes of pollen, dinoflagellate cysts, fresh-water algae and plant cuticles, suggesting "episodic flash flood" events of the Senegal River. The driest phase developed after about 2100 cal yr BP.

  17. Correlation between Cu mineralization and major faults using multifractal modelling in the Tarom area (NW Iran)

    Science.gov (United States)

    Nouri, Reza; Jafari, Mohammad Reza; Arian, Mehran; Feizi, Faranak; Afzal, Peyman

    2013-10-01

    The Tarom 1: 100,000 sheet is located within the Cenozoic Tarom-Hashtjin volcano-plutonic belt, NW Iran. Reconstruction of the tectonic and structural setting of the hydrothermal deposits is fundamental to predictive models of different ore deposits. Since fractal/multifractal modelling is an effective instrument for separation of geological and mineralized zones from background, therefore Concentration-Distance to Major Fault (C-DMF) fractal model and distribution of Cu anomalies were used to classify Cu mineralizations according to their distance to major faults. Application of the C-DMF model for the classification of Cu mineralization in the Tarom 1: 100,000 sheet reveals that the main copper mineralizations have a strong correlation with their distance to major faults in the area. The distances of known copper mineralizations having Cu values higher than 2.2 % to major faults are less than 10 km showing a positive correlation between Cu mineralization and tectonic events. Moreover, extreme and high Cu anomalies based on stream sediments and lithogeochemical data were identified by the Number-Size (N-S) fractal model. These anomalies have distances to major faults less than 10 km and validate the results derived via the C-DMF fractal model. The C-DMF fractal modelling can be utilized for the reconnaissance and prospecting of magmatic and hydrothermal deposits.

  18. 30 CFR 56.14131 - Seat belts for haulage trucks.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Seat belts for haulage trucks. 56.14131 Section... Equipment Safety Devices and Maintenance Requirements § 56.14131 Seat belts for haulage trucks. (a) Seat belts shall be provided and worn in haulage trucks. (b) Seat belts shall be maintained in...

  19. Evolución metalogenética de las Sierras Pampeanas de Córdoba y sur de Santiago del Estero: Ciclos prepampeano y pampeano Metallogenic evolution of the Sierras Pampeanas of Córdoba and south of Santiago del Estero: Prepampean and Pampean cycles

    Directory of Open Access Journals (Sweden)

    D. Mutti

    2005-03-01

    éticas más significativas.This hypothesis of metallogenic evolution of the Sierras Pampeaneas of Córdoba and south of Santiago del Estero proposes the existence of five metallogenic stages, two of wich are treated in this paper: stage 1 belongs to the prepampean extensional cycle and is connected with the Neoproterozoic opening and expansion of the proto-Atlantic ocean. During this stage submarine volcanogenic deposits were developed such as Cu-Fe (Zn-Au-Ag-Co in basalts, W (B-F-Zn in impure limestones and dolomites, and Fe in silicoclastic sediments, as well as transition occurrences from them to MVT deposits of Cu (Au-Ag and Pb- Zn (Ag-Cu-Au in impure limestones and dolomites. Chromite magmatic deposits in mantle tectonites and of Fe-Ti in ultramaficmafic rocks in the transition crust-mantle zone are also related to stage 1. Distribution of the Prepampean deposits and their space relationship with the main submarine volcanogenic, SEDEX and MVT áreas in the proto-atlantic ocean are placed on a global reconstruction for Neoproterozoic age. The compressive Pampean - Famatinian cycle comprises two stages. Metallogenic stage 2 (Neoproterozoic - early Cambrian corresponds to the pampean orogenic cycle, during which numerous deformation structures and magmatism were developed. During this stage magmatic-metamorphic occurrences of Fe-Ti in ultramafic and mafic dikes in mantle tectonites, metasomatic occurrences of Fe-Ti in rodingites and Be-Li-U-ETR rich pegmatites were generated, besides transformation events comprising metamorphism, deformation, remobilization and recrystallization occurred in deposits of Cr, Cu-Fe (Zn-Au-Ag- Co, W (B-F-Zn, Cu (Au-Ag, Pb-Zn (Ag-Cu-Au and Fe, which affected their magnetic response.Ore deposits and occurrences included in the above metallogenic stages are distributed in this study in belts related to megastructures activated during the Prepampean and Pampean cycles and the most significant petrogenétic associations are indicated.

  20. The Central Iberian arc, an orocline centered in the Iberian Massif and some implications for the Variscan belt

    Science.gov (United States)

    Martínez Catalán, José R.

    2012-07-01

    An arcuate structure, comparable in size with the Ibero-Armorican arc, is delineated by Variscan folds and magnetic anomalies in the Central Iberian Zone of the Iberian Massif. Called the Central Iberian arc, its sense of curvature is opposite to that of the Ibero-Armorican arc, and its core is occupied by the Galicia-Trás-os-Montes Zone of NW Iberia, which includes the Rheic suture. Other zones of the Iberian Massif are bent by the arc, but the Ossa-Morena and South Portuguese zones are not involved. The arc formed during the Late Carboniferous, at final stages of thermal relaxation and collapse, and an origin related with right-lateral ductile transpression at the scale of the Variscan belt is proposed. The Central Iberian arc explains the width of the Central Iberian Zone, clarifies the position of the allochthonous terranes of NW Iberia, and opens new perspectives for correlations with the rest of the Variscan belt, in particular, with the Armorican Massif, whose central zone represents the continuation of the southwest branch of the arc detached by strike-slip tectonics.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-10-01

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

  2. Seat Belt Usage on School Buses.

    Science.gov (United States)

    Farmer, Ernest

    1985-01-01

    Studies on seat belt usage conducted under contract with governmental organizations or prepared by professional societies, state and local organizations, and transportation specialists have made significant contributions, but none has successfully resolved the issue. (MLF)

  3. Handbook Timing Belts Principles, Calculations, Applications

    CERN Document Server

    Perneder, Raimund

    2012-01-01

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

  4. Radiation Belt Storm Probe (RBSP) Mission

    Science.gov (United States)

    Sibeck, D. G.; Fox, N.; Grebowsky, J. M.; Mauk, B. H.

    2009-01-01

    Scheduled to launch in May 2012, NASA's dual spacecraft Living With a Star Radiation Belt Storm Probe mission carries the field and particle instrumentation needed to determine the processes that produce enhancements in radiation belt ion and electron fluxes, the dominant mechanisms that cause the loss of relativistic electrons, and the manner by which the ring current and other geomagnetic phenomena affect radiation belt behavior. The two spacecraft will operate in low-inclination elliptical lapping orbits around the Earth, within and immediately exterior to the Van Allen radiation belts. During course of their two year primary mission, they will cover the full range of local times, measuring both AC and DC electric and magnetic fields to 10kHz, as well as ions from 50 eV to 1 GeV and electrons with energies ranging from 50 eV to 10 MeV.

  5. Radiation Belt and Plasma Model Requirements

    Science.gov (United States)

    Barth, Janet L.

    2005-01-01

    Contents include the following: Radiation belt and plasma model environment. Environment hazards for systems and humans. Need for new models. How models are used. Model requirements. How can space weather community help?

  6. The Compositional Structure of the Asteroid Belt

    CERN Document Server

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

    2015-01-01

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

  7. Eccentricity distribution in the main asteroid belt

    CERN Document Server

    Malhotra, Renu

    2016-01-01

    The observationally complete sample of the main belt asteroids now spans more than two orders of magnitude in size and numbers more than 64,000 (excluding collisional family members). We undertook an analysis of asteroids' eccentricities and their interpretation with simple physical models. We find that Plummer's (1916) conclusion that the asteroids' eccentricities follow a Rayleigh distribution holds for the osculating eccentricities of large asteroids, but the proper eccentricities deviate from a Rayleigh distribution: there is a deficit of eccentricities smaller than $\\sim0.1$ and an excess of larger eccentricities. We further find that the proper eccentricities do not depend significantly on asteroid size but have strong dependence on heliocentric distance: the outer asteroid belt follows a Rayleigh distribution, but the inner belt is strikingly different. Eccentricities in the inner belt can be modeled as a vector sum of a primordial eccentricity vector of random orientation and magnitude drawn from a Ra...

  8. Drive Alive: Teen Seat Belt Survey Program

    OpenAIRE

    Burkett, Katie M.; Davidson, Steve; Cotton, Carol; Barlament, James; Loftin, Laurel; Stephens, James; Dunbar, Martin; Butterfield, Ryan

    2010-01-01

    Objective: To increase teen seat belt use among drivers at a rural high school by implementing the Drive Alive Pilot Program (DAPP), a theory-driven intervention built on highway safety best practices. Methods: The first component of the program was 20 observational teen seat belt surveys conducted by volunteer students in a high school parking lot over a 38-month period before and after the month-long intervention. The survey results were published in the newspaper. The second compo...

  9. Jupiter's Radiation Belts: Can Pioneer 10 Survive?

    Science.gov (United States)

    Hess, W N; Birmingham, T J; Mead, G D

    1973-12-07

    Model calculations of Jupiter's electron and proton radiation belts indicate that the Galilean satellites can reduce particle fluxes in certain regions of the inner magnetosphere by as much as six orders of magnitude. Average fluxes should be reduced by a factor of 100 or more along the Pioneer 10 trajectory through the heart of Jupiter's radiation belts in early December. This may be enough to prevent serious radiation damage to the spacecraft.

  10. Seat-belt message and the law?

    Science.gov (United States)

    Sengupta, S K; Patil, N G; Law, G

    1989-09-01

    This paper attempts to draw together available information on the use of seat belts, one of the most important safety devices for a person in a car. Considering the high rate of mortality and morbidity due to road traffic accidents in Papua New Guinea the authors strongly feel that seat-belt usage should be made compulsory. When one looks at the history of the implementation of such a successful countermeasure in other countries it seems that legislation is the only answer.

  11. Eccentricity distribution in the main asteroid belt

    Science.gov (United States)

    Malhotra, Renu; Wang, Xianyu

    2017-03-01

    The observationally complete sample of the main belt asteroids now spans more than two orders of magnitude in size and numbers more than 64 000 (excluding collisional family members). We undertook an analysis of asteroids' eccentricities and their interpretation with simple physical models. We find that a century old conclusion that the asteroids' eccentricities follow a Rayleigh distribution holds for the osculating eccentricities of large asteroids, but the proper eccentricities deviate from a Rayleigh distribution; there is a deficit of eccentricities smaller than ∼0.1 and an excess of larger eccentricities. We further find that the proper eccentricities do not depend significantly on asteroid size but have strong dependence on heliocentric distance; the outer asteroid belt follows a Rayleigh distribution, but the inner belt is strikingly different. Eccentricities in the inner belt can be modelled as a vector sum of a primordial eccentricity vector of random orientation and magnitude drawn from a Rayleigh distribution of parameter ∼0.06, and an excitation of random phase and magnitude ∼0.13. These results imply that when a late dynamical excitation of the asteroids occurred, it was independent of asteroid size and was stronger in the inner belt than in the outer belt. We discuss implications for the primordial asteroid belt and suggest that the observationally complete sample size of main belt asteroids is large enough that more sophisticated model-fitting of the eccentricities is warranted and could serve to test alternative theoretical models of the dynamical excitation history of asteroids and its links to the migration history of the giant planets.

  12. Major Fault Systems and Mountain Building Processes in the Tibetan Foreland and Beishan Region, NW China

    Science.gov (United States)

    Cunningham, D.; Zhang, J.

    2012-04-01

    In regions north of Tibet, active deformation associated with the Indo-Eurasia collision is diffusely distributed within large areas of NW China, Mongolia and S and SE Siberia. These regions are dominated by intraplate strike-slip and transpressional reactivation of Palaeozoic terrane collages. Because of relatively low historical seismicity, the Beishan region immediately north of Tibet is generally regarded as tectonically uninteresting from a neotectonic standpoint. However, our preliminary work in the region coupled with satellite image analysis indicates that the region is cut by at least five major sinistral strike-slip fault systems that are potentially active and which parallel the Altyn Tagh fault which bounds northern Tibet directly to the south. These fault systems generate localised uplifts within the Beishan and show typical geomorphological characteristics of active intracontinental deforming belts such as sharply defined mountain fronts, Quaternary alluvial fan complexes and tilted Cretaceous peneplain remnants. Specifically, the Yushi Shan and Mazong Shan are Late Cenozoic restraining bends that show clear evidence for Quaternary thrusting and uplift. Other minor localised uplifts also appear fault-controlled. However, at first-order, regional Beishan topography is difficult to explain by Late Cenozoic upper crustal faulting, unlike Tibet to the south and the Gobi Altai to the north. Directly adjacent to Tibet's northern margin, the Sanweishan and Nanjieshan blocks are thrust-bound basement-cored uplifts that interrupt the Tibetan sedimentary foreland in the Dunhuang-Anxi region. The faults that cut and bound these minor ranges appear to define an evolving transpressional duplex with north-directed thrusting, but perhaps surprisingly, also south-directed thrusting back towards the high Plateau. As noted by others, the Altyn Tagh Fault defines a profound topographic and structural boundary in Central Asia with significant differences in contractional

  13. Re-Os Dating of the Pulang Porphyry Copper Deposit in Zhongdian, NW Yunnan, and Its Geological Significance

    Institute of Scientific and Technical Information of China (English)

    ZENG Pusheng; HOU Zengqian; WANG Haiping; QU Wenjun; MENG Yifeng; YANG Zhusen; LI Wenchang

    2004-01-01

    The Pulang porphyry copper deposit is located in the Zhongdian island arc belt, NW Yunnan, in the central part of the Sanjiang area, SW China, belonging to the southern segment of the Yidun island arc belt on the western margin of the Yangtze Platform. In the Yidun island arc, there occur well-known "Gacun-style" massive sulfide deposits in the northern segment and plenty of porphyry copper deposits in the southern segment, of which the Pulang porphyry copper deposit is one of the representatives. Like the Yulong porphyry copper deposit, this porphyry copper deposit is also one of the most important porphyry copper deposits in the eastern Qinghai-Tibet Plateau. But it is different from other porphyry copper deposits in the eastern Qinghai-Tibet Plateau (e.g. those in the Gangdise porphyry copper belt and Yulong porphyry copper belt) in that it formed in the Indosinian period, while others in the Himalayan period. Because of its particularity among the porphyry copper deposits of China, this porphyry copper deposit is of great significance for the study of the basic geology and the evaluation and prediction of mineral resources in the Zhongdian island arc belt.However, no accurate chronological data are available for determining the timing of mineralization of the porphyry copper deposit. By field observation in the study area and Re-Os dating of molybdenite and K-Ar dating of hydrothermal minerals and whole rock from the typical geological bodies, the timing of mineralization of the porphyry copper deposit has systematically been determined for the first time. The K-Ar age for the hydrothermal mineralization of biotite-quartz monzonitic porphyry that has undergone patassic silicate (biotite and K-feldspar) alteration ranges from 235.4±2.4 to 221.5±2.0 Ma and the Re-Os age for molybdenite in the quartz-molybdenite stage is ~213±3.8 Ma. These data are very close to each other, suggesting that the ore-forming processes of the Pulang porphyry copper deposit was

  14. Jupiter's magnetosphere and radiation belts

    Science.gov (United States)

    Kennel, C. F.; Coroniti, F. V.

    1979-01-01

    Radioastronomy and Pioneer data reveal the Jovian magnetosphere as a rotating magnetized source of relativistic particles and radio emission, comparable to astrophysical cosmic ray and radio sources, such as pulsars. According to Pioneer data, the magnetic field in the outer magnetosphere is radially extended into a highly time variable disk-shaped configuration which differs fundamentally from the earth's magnetosphere. The outer disk region, and the energetic particles confined in it, are modulated by Jupiter's 10 hr rotation period. The entire outer magnetosphere appears to change drastically on time scales of a few days to a week. In addition to its known modulation of the Jovian decametric radio bursts, Io was found to absorb some radiation belt particles and to accelerate others, and most importantly, to be a source of neutral atoms, and by inference, a heavy ion plasma which may significantly affect the hydrodynamic flow in the magnetosphere. Another important Pioneer finding is that the Jovian outer magnetosphere generates, or permits to escape, fluxes of relativistic electrons of such intensities that Jupiter may be regarded as the dominant source of 1 to 30 MeV cosmic ray electrons in the heliosphere.

  15. THE GOULD'S BELT DISTANCE SURVEY

    Directory of Open Access Journals (Sweden)

    L. Loinard

    2011-01-01

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

  16. Metallogenic age and ore genesis of the Badaguan porphyry copper-molybdenum deposit in Inner Mongolia%内蒙古八大关斑岩型铜钼矿床形成时代与成因分析

    Institute of Scientific and Technical Information of China (English)

    李春风; 柳振江; 宓奎峰; 王建平; 刘瑞斌; 邹君宇; 王忠宝

    2014-01-01

    八大关铜钼矿床是内蒙古德尔布干成矿带中段的一个典型斑岩型矿床,绢英岩化、青磐岩化等蚀变分带明显,矿体呈条带状赋存于印支期石英闪长岩中。笔者通过运用Re-Os同位素年代学、元素地球化学以及硫同位素等测试手段,初步分析了该矿床的成矿过程。辉钼矿Re-Os同位素加权平均模式年龄为(226.7±2.4) Ma,表明该矿床形成于晚三叠世早期;元素地球化学分析显示含矿岩体属于中钾含量的钙碱性岩石系列,为I型花岗岩,产于火山弧构造环境,具有活动板块边缘的特征,矿化过程中,成矿母岩的稀土元素总量逐渐降低,轻重稀土发生明显分异;金属硫化物的δ34S值介于+0.5‰~+4.8‰,具有幔源硫的特征。综合分析认为八大关铜钼矿床形成于晚三叠世,蒙古-鄂霍茨克洋向南俯冲过程中,深部岩浆活动带来了大量成矿物质,洋壳部分熔融侵位到额尔古纳地块之上,随热液流体迁移的Cu、Mo等元素与源自地幔的硫相结合,最终富集成矿。%Located in the middle of Derbugan metallogenic belt in Inner Mongolia, the Badaguan copper-molybdenum deposit is a typical porphyry deposit with obvious phyllic and propylitic alteration zones. The banded orebodies occur in Triassic quartz diorite. By such means as Re-Os isotope geochronology, element geochemistry and sulfur isotope geochemistry, the authors preliminarily analyzed the ore-forming process of the deposit. Re-Os dating of molybdenite gave a weighted average model age of (226.7 ± 2.4) Ma, implying that the deposit was formed in the early Late Triassic. Element geochemical analysis shows that the ore-bearing rocks were I-type granites and belonged to calc-alkaline rock series with moderate content of potassium, which were produced in a volcanic arc environment with characteristic active plate edges. During the ore-forming process, ΣREE in ore-bearing rock gradually

  17. Extraction of Prospecting Information for the Lvliangshan Copper Deposit,Qinghai Province and its Metallogenic Prediction%青海绿梁山铜矿找矿信息的提取与成矿预测

    Institute of Scientific and Technical Information of China (English)

    徐广东; 郑有业; 许荣科; 徐萌萌; 徐永利; 吴亮

    2013-01-01

    绿梁山铜矿位于柴达木盆地北缘,属柴北缘成矿带,它是中国西部重要的多金属成矿区带之一.通过对绿梁山铜矿详细的地质调查、水系沉积物测量、高精度磁测扫面和遥感解译等工作,在系统研究其成矿地质条件、地球化学特征、地球物理特征和遥感影像特征的基础上,进一步筛选与矿化有关的异常信息,归纳并提取了地物化遥找矿信息:硅化、黄铁矿化、绿泥石化、绿帘石化、绢云母化等近矿围岩蚀变是寻找铜矿床的间接标志;遥感解译的复合环形构造与遥感蚀变信息叠加区是找矿有利区;在Cu、Au、Bi异常区沿铜矿化向北西存在较多的铜金矿化线索;强磁异常梯度带分布是最显著的深大断裂位置反映;显著的水热蚀变晕也是寻找该类矿床的重要遥感标志.结合以上特征在绿梁山找矿远景区内共圈定出Ⅰ、Ⅱ类靶区共3个.%The Lvliangshan copper deposit located in the northern marginal of the Qaidam Basin belongs to the East Kunlun metallogenic belt,and is one of the important metal mineralization zones in western China.Based on detailed geology surveys,drainage sediment measurements,high-accuracy magnetic sweeping and remote sensing interpretations,in combination with the mineralization conditions,geochemical characteristics,geophysical characteristics and remote sensing image features,we selected anomaly information relevant to mineralization,and extracted and summarized prospecting indicators.The near-ore wall-rock alterations such as silication,pyritization,chloritization,epidotization and sericitization are an indirect symbol for prospecting copper deposits.The areas with superposed composite circular structures from remote sensing interpretations and alteration information are favorable for ore prospecting.Northwest of the anomaly area of Cu,Au and Bi exist many copper and gold mineralization clues.The distribution of strong magnetic anomaly gradient

  18. Deciphering structures and deformation of the Obuom Gold Prospect, Central Ashanti Belt of Ghana: A lithostructural approach

    Science.gov (United States)

    Nunoo, Samuel; Manu, J.; Olarewaju, V. O.; Asiedu, D. K.; Nude, P. M.

    2016-12-01

    The Obuom Gold Prospect is located in the central part of the Paleoproterozoic Birimian Ashanti belt of southwest Ghana. The prospect is approximately 45 km2 and is underlain by basalt, andesite and dacite volcanic beds, graphitic and chlorite phyllites of sedimentary origin and granites. Published works on the Obuom geological terrane, using gravity models, showed that, the structures are more complex than previously thought and may involve multiple thrust slices. This research identified two deformational episodes; the first has a remarkable sinistral sense probably synchronous with an Eoeburnean event with the second, an overprint of dextral shearing during the Eburnean event. The first episode, Do1 is characterized by NW-SE compression which resulted in subvertical NE-SW trending S1 axial plane metamorphic foliation in tight to isoclinal F1 folds with NW-SE trending L1 lineations. The second episode, Do2 indicates continuous shortening which produced nearly upright F2 folds with east-west striking axial planes, slight plunging hinges and associated subparallel crenulation cleavages. The first deformational event Do1 which represent NW-SE compression is observed affecting only the Sefwi Group. The Do2 resulting from N-S compression affected both the Sefwi and Kumasi Groups.

  19. CRED REA Belt Surveys of Coral Population and Disease Assessments at Kure Atoll, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  20. 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.

  1. CRED REA Belt Surveys of Coral Population and Disease Assessments at Midway Atoll, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  2. CRED REA Belt Surveys of Coral Population and Disease Assessments at French Frigate Shoals, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  3. CRED REA Belt Surveys of Coral Population and Disease Assessments at Laysan Island, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  4. CRED REA Belt Surveys of Coral Population and Disease Assessments at Pearl And Hermes Atoll, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  5. CRED REA Belt Surveys of Coral Population and Disease Assessments at Lisianski Island, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  6. CRED REA Belt Surveys of Coral Population and Disease Assessments at Maro Reef, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  7. Decay rate of the second radiation belt.

    Science.gov (United States)

    Badhwar, G D; Robbins, D E

    1996-01-01

    Variations in the Earth's trapped (Van Allen) belts produced by solar flare particle events are not well understood. Few observations of increases in particle populations have been reported. This is particularly true for effects in low Earth orbit, where manned spaceflights are conducted. This paper reports the existence of a second proton belt and it's subsequent decay as measured by a tissue-equivalent proportional counter and a particle spectrometer on five Space Shuttle flights covering an eighteen-month period. The creation of this second belt is attributed to the injection of particles from a solar particle event which occurred at 2246 UT, March 22, 1991. Comparisons with observations onboard the Russian Mir space station and other unmanned satellites are made. Shuttle measurements and data from other spacecraft are used to determine that the e-folding time of the peak of the second proton belt. It was ten months. Proton populations in the second belt returned to values of quiescent times within eighteen months. The increase in absorbed dose attributed to protons in the second belt was approximately 20%. Passive dosimeter measurements were in good agreement with this value.

  8. Structural and lithologic relationships in the Raleigh metamorphic belt near Lake Gaston, Virginia and North Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, P.E.; Horton, J.W. Jr. (Geological Survey, Reston, VA (United States))

    1993-03-01

    Preliminary results of mapping along the NC-VA State line eastward from the Buggs Is. granite about 35 km to the Hollister fault zone yield new information about structural and lithologic relationships in the Raleigh metamorphic belt. The layered rocks are predominantly two-mica schist and sillimanite-mica schist interlayered with lesser amounts of muscovite-biotite-quartz-plagioclase paragneiss and hornblende-biotite gneiss. The overall rock assemblage here differs from those along strike near Goochland, VA, and near Raleigh, NC, and is reminiscent of an accretionary complex. Bodies of foliated to massive two-mica granite are abundant and commonly contain garnet. One body, the Wise pluton, contains a N--NW-striking, steeply dipping foliation, but the intrusive contact of the granite with the metamorphic rocks is discordant. The most prominent regional foliation, parallel to transposed compositional layering, is axial planar to relict, reclined, isoclinal outcrop-scale folds. This foliation is folded at both outcrop and map scale by open folds plunging NW and SW. Some foliated, two-mica granite sheets are warped by the open folds; other bodies of similar granite cut across these folds. Sillimanite needles are locally aligned with the hinges of some of the open folds, an indication that sillimanite-muscovite-grade metamorphism was associated with this folding event. The two-mica granites resemble other late Paleozoic granites in the region. If these granites prove to be late Paleozoic (Alleghanian), then the deformation and metamorphism that produced sillimanite along the hingelines also must be Alleghanian. Relatively younger, NW- and SE-plunging crenulations and chevron folds are associated with a crenulation cleavage that dips steeply NE or SW. Sillimanite needles are folded by these crenulations. Crenulation cleavage and related folds may have developed in response to transpression of these rocks between the dextral Lake Gordon and Hollister mylonite zones.

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

    NARCIS (Netherlands)

    2010-01-01

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

  10. Flat belt continuously variable high speed drive

    Energy Technology Data Exchange (ETDEWEB)

    Kumm, E.L.

    1992-02-01

    A study was undertaken at Kumm Industries funded by DOE in the NBS/DOE Energy-Related Inventions Program starting in August 1990 to design, construct and test a novel very high speed flat belt drive. The test arrangement as shown in Figure 1 consists of a multiple belt-pulley configuration that transmits power from a low speed (2000--4000 RPM) input to a small pulley turbine'' (27,000 to 55,000 RPM) and then to the low speed output variable radius pulley (2000--5000 RPM) via a special self-active tensioner. Transmitting 25 HP to and from the turbine'' corresponds to obtaining 50 HP in one direction only in a possible turbo compounded engine application. The high speed of the turbine'' belts, i.e. 100 meters/sec. at 55,000 RPM, while transferring substantial power is a new much higher operating regime for belts. The study showed that the available belts gave overall test rig efficiencies somewhat above 80% for the higher speeds (50,000 RPM) and higher powers (corresponding to above 90% in the turbocompound application) and a significantly better efficiencies at slightly lower speeds. The tests revealed a number of improved approaches in the design of such high speed drives. It appears that there is considerable possibility for further improvement and application of such equipment.

  11. Sediment aggradation and erosional dynamics of intermontane basins in NW Argentina

    Science.gov (United States)

    Bookhagen, Bodo; Castino, Fabiana; Purinton, Ben; Strecker, Manfred

    2017-04-01

    The NW Argentine Andes constitute the Andean Plateau (Altiplano-Puna), the second-largest orogenic plateau on Earth, an internally drained highland with a mean elevation of 4.0 ± 0.5 km (±2 sigma). The Puna is flanked by the externally drained Eastern Cordillera thrust belt and the adjacent broken foreland that are connected to the Atlantic Ocean. These mountain ranges lie in the south-central Andes and are characterized by steep topographic and climatic gradients: The first windward topographic rise east of the Puna forms a significant orographic barrier resulting in high orographic rainfall causing some of the wettest places on Earth. In contrast, the higher-elevation areas of the windward flanks become progressively drier westward, until arid conditions are attained in the central Puna. During the Quaternary the south-central Andes have repeatedly experienced significant paleoclimatic changes associated with deeper penetration of moisture into the orogen, and thus an orogenward shift of the climate gradient. This mechanism has resulted in large variations in erosion dynamics and sediment transfer toward the foreland, resulting in thick valley fills and multiple terrace levels. At much shorter timescales, climate variability during the Holocene has caused similar, yet less pronounced hydrologic trends and associated sedimentation- and erosion processes. Here, we use a time series of Digital Elevation Models (DEMs) to reconstruct land-level changes in the intramontane basins in NW Argentina. We generated the DEMs and height measurements based on stereo airphotos from the 1980s, ASTER satellite imagery, ICESat and dGPS measurements during the past decade, and several TerraSAR-X and TanDEM-X CoSSC pairs starting in 2013. Our data show a strong signal of fluvial sediment aggradation during the past 30 years, in places up to 0.5m per decade, which explains the regionally observed, modern sediment accumulation in basins that has caused major infrastructural problems

  12. The effects of Maine's change to primary seat belt law on seat belt use and public perception and awareness.

    Science.gov (United States)

    Chaudhary, Neil K; Tison, Julie; Casanova, Tara

    2010-04-01

    Maine upgraded its seat belt law to primary enforcement on September 20, 2007. Belt observations during the day and night were conducted along with awareness surveys in state licensing offices. Both daytime and nighttime observed belt use increased in the months following implementation of the law (daytime 77-84%; night 69-81%). Although daytime belt use was generally higher, nighttime belt use showed a greater increase than daytime belt use. Awareness surveys indicated that Maine motorists were clearly aware of the law change and its consequences. Survey respondents also indicated having heard both messages about enforcement and messages encouraging belt use. Primary seat belt laws may have a stronger effect on belt use at night--when risk is higher--than during the day.

  13. Friction and Wear in Timing Belt Drives

    Directory of Open Access Journals (Sweden)

    B. Stojanovic

    2010-09-01

    Full Text Available Timing belt tooth goes into contact with a drive pulley, stretched to the maximum, because of the previous tension. When the contact begins the peak of the belt tooth makes the contact with the outer surface of the pulley teeth. The process of the teeth entering into the contact zone is accompanied with the relative sliding of their side surfaces and appropriate friction force. The normal force value is changing with the parabolic function, which also leads to the changes of the friction force. The biggest value of the normal force and of the friction force is at the tooth root. Hollow between teeth and the tip of the pulley teeth are also in contact. Occasionally, the face surface of the belt and the flange are also in contact. The friction occurs in those tribomechanical systems, also. Values of these friction forces are lower compared with the friction force, which occurs at the teeth root.

  14. Ionospheric heating for radiation-belt control

    Energy Technology Data Exchange (ETDEWEB)

    Burke, W.J.; Villalon, E.

    1990-10-01

    Pitch-angle scattering interactions of electromagnetic waves in the ELF/VLF bands with trapped electrons, as formulated by Kennel and Petschek 1, describe the dynamics of the freshly filled radiation belts flux tubes. The natural existence of a slot region with electron fluxes below the Kennel-Petschek limit requires non-local wave sources. We describe a set of planned, active experiments in which VLF radiation will be injected from ground and space based transmitters in conjunction with the CRRES satellite in the radiation belts. These experiments will measure the intensity of waves driving pitch-angle diffusion and the electron energies in gyroresonance with the waves. An ability to reduce the flux of energetic particles trapped in the radiation belts by artificial means could improve the reliability of microelectronic components on earth-observing satellites in middle-altitude orbits.

  15. Drive Alive: Teen Seat Belt Survey Program

    OpenAIRE

    Loftin, Laurel; Barlament, James; Cotton, Carol; Davidson, Steve M; Burkett, Katie M.; Stephens, James

    2010-01-01

    Objective: To increase teen seat belt use among drivers at a rural high school by implementing the Drive Alive Pilot Program (DAPP), a theory-driven intervention built on highway safety best practices.Methods: The first component of the program was 20 observational teen seat belt surveys conducted by volunteer students in a high school parking lot over a 38-month period before and after the month-long intervention. The survey results were published in the newspaper. The second component was t...

  16. Development of belt conveyor driving system

    Institute of Scientific and Technical Information of China (English)

    FU Jun-qing(付峻青); WANG Cong(王聪); HUO Wei(霍伟)

    2004-01-01

    A short review for the existing various driving methods for belt conveyor was given, which include the analysis and comparison about the advantages, disadvantages and suitable application range of these methods. Based on this the variable-frequency-control(VFC) method for belt conveyor drive was fully discussed with focus on its application in medium-high voltage range. The principle of Neutral Point Clamped (NPC) Three-Level Inverter using high-voltage IGBTs together with the control strategy of rotor field-oriented vector control for induction motor drive were illustrated.

  17. The radiation belt of the Sun

    CERN Document Server

    Gruzinov, Andrei

    2013-01-01

    For a given solar magnetic field, the near-Sun (phase-space) density of cosmic ray electrons and positrons of energy above about 10GeV can be calculated from first principles, without any assumptions about the cosmic ray diffusion. This is because the sunlight Compton drag must be more important than diffusion. If the solar magnetic field has an appreciable dipole component, the electron/positron density should have a belt-like dent, perhaps extending to several solar radii. The belt structure appears because the quasi-bound orbits are depopulated by the sunlight Compton drag.

  18. Composite Microdiscs with a Magnetic Belt

    DEFF Research Database (Denmark)

    Knaapila, Matti; Høyer, Henrik; Helgesen, Geir

    2015-01-01

    We describe an emulsion-based preparation of patchy composite particles (diameter of 100-500 mu m) consisting of a disclike epoxy core and a belt of porous polystyrene particles (diameter of 30 mu m) with magnetite within the pores. Compared to the magnetically uniform polystyrene particles......, the spontaneous aggregation of composite particles is suppressed when dispersed into liquid, which is attributed to the increased particle size, reduced magnetic susceptibility, and the shape of the magnetic domain distribution within the particles (spherical versus a belt). When the composite particles...

  19. Ionospheric heating for radiation belt control

    Science.gov (United States)

    Burke, William J.; Villalon, Elena

    1990-10-01

    Pitch-angle scattering interactions of electromagnetic waves in the ELF/VLF bands with trapped electrons describe the dynamics of the freshly filled radiation belts flux tubes. The natural existence of a 'slot' region with electron fluxes below the Kennel-Petschek limit requires non-local wave sources. A set of planned, active experiments is described in which VLF radiation is injected from ground and space band transmitters in conjunction with the Combined Release and Radiation Effects Satellite in the radiation belts. These experiments can measure the intensity if waves driving pitch-angle diffusion and the electron energies in gyroresonance with the waves.

  20. CALCULATION OF TENSION FORCE OF BELT CONVEYOR

    Directory of Open Access Journals (Sweden)

    Ismet Ibishi

    2012-12-01

    Full Text Available In this paper is done the explanation on tension fashion of the belt conveyor which is employed in Kosovo Energy Corporation – KEK, for coal transportation to provide electric power plant. The aim of the paper enables to recognize tension forces not to pass with deformation of belt so that this problem will damage the workingprocess. Work principle is based on initial tension and tension during working process. The fact is known that the tension starts from the carriage on the way to tension mechanization, so forces on the rope passing through pulley there has to dominate the friction coefficient. All this process is related to economy of transportationmechanism.

  1. Volcanic-hosted massive sulfide deposits in the Murchison greenstone belt, South Africa

    Science.gov (United States)

    Schwarz-Schampera, Ulrich; Terblanche, Hennie; Oberthür, Thomas

    2010-02-01

    The Archean Murchison greenstone belt, Limpopo Province, South Africa, represents a rifted epicontinental arc sequence containing the largest volcanic-hosted massive sulfide (VMS) district in Southern Africa. The so-called Cu-Zn line is host to 12 deposits of massive sulfide mineralization including: Maranda J, LCZ, Romotshidi, Mon Desir, Solomons, and Mashawa with a total tonnage of three million metric tons of very high grade Zn, subordinate Cu, and variable Pb and Au ore. The deposits developed during initial phases of highly evolved felsic volcanism between 2,974.8 ± 3.6 and 2,963.2 ± 6.4 Ma and are closely associated with quartz porphyritic rhyolite domes. Elevated heat supply ensured regional hydrothermal convection along the entire rift. Recurrent volcanism resulted in frequent disruption of hydrothermal discharge and relative short-lived episodes of hydrothermal activity, probably responsible for the small size of the deposits. Stable thermal conditions led to the development of mature hydrothermal vent fields from focused fluid discharge and sulfide precipitation within thin layers of felsic volcaniclastic rocks. Two main ore suites occur in the massive sulfide deposits of the “Cu-Zn line”: (1) a low-temperature venting, polymetallic assemblage of Zn, Pb, Sb, As, Cd, Te, Bi, Sn, ±In, ±Au, ±Mo occurring in the pyrite- and sphalerite-dominated ore types and (2) a higher temperature suite of Cu, Ag, Au, Se, In, Co, Ni is associated with chalcopyrite-bearing ores. Sphalerite ore, mineralogy, and geochemical composition attest to hydrothermal activity at relatively low temperatures of ≤250 °C for the entire rift, with short-lived pulses of higher temperature upflow, reflected by proportions of Zn-rich versus Cu-rich deposits. Major- and trace-metal composition of the deposits and Pb isotope signatures reflect the highly evolved felsic source rock composition. Geological setting, host rock composition, and metallogenesis share many similarities not

  2. Isotopic and magnetic provenance characterization of distal IRD in the Galicia Interior Basin (NW Iberia)

    Science.gov (United States)

    Plaza-Morlote, Maider; Rey, Daniel; Francisco Santos, Jose; Ribeiro, Sara; Bernabeu, Ana; Mohamed, Kais; Heslop, David; Rubio, Belén; Martins, Virginia

    2016-04-01

    The sediments of the Galicia Interior Basin in NW Iberia Margin are of particular palaeoclimatic interest as they are located at the boundary where the climatic oscillations of the glacial interval were interrupted by extreme events such as Heinrich events. These events are well characterized in Northern North Atlantic areas, but little is known about their occurrence beyond the Ruddiman belt. This study presents a combined environmagnetic and geochemical approach to the provenance and characterization of distal ice-rafted detritus (IRD) that occurred during the last glacial period in core CI12PC3 from the Galicia Interior Basin. The last six Heinrich Layers were identified by their magneto-mineralogical and geochemical properties. Their Sr and Nd isotopic signatures indicated that the Laurentide Ice Sheet was the major source for HL1, HL2, HL4 and HL5. However, the European ice sheets also influenced the initial development stages of HL1, HL2, HL4. HL3, HL6 and partially HL1, HL2 and HL4 were influenced by more juvenile provinces, such as Iceland/Faroes sheets and/or by the Fram Strait/East Greenland nearby areas. Separate provenance analyses of the coarse and fine fractions in the studied Heinrich Layers also indicated that IRDs and glacial flour sources might not always be the same. Our results shed unequivocal evidence that Canadian-sourced distal IRD are preceded by European-sourced IRD, at least from the H4. In our view, LIS and EIS instabilities registered in the Iberian Margin respond to the same climate forcing at different velocities.

  3. Aoyitake plagiogranite in western Tarim Block, NW China:Age, geochemistry, petrogenesis and its tectonic implications

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Chuanlin; YU; Haifeng; YE; Haimin; ZHAO; Yu

    2006-01-01

    SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW China. The plagiogranite intruded the Middle Proterozoic and Lower Carboniferous with an exposure area of ca. 60 km2 and crystallized at 330.7±4.8Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite.Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally.The granites are sodic with Na/K ratios (molar) between 4 and 87. Total REE (50-220 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), medium negative Eu anomalies (δEu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2DM model ages of 470 to 580 Ma and positive εNd(331 Ma) values of 6.23 to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca.50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive fractionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

  4. Pre-Andean Rotations in NW Argentina: a Clue to a Possible Tectonic Model?

    Science.gov (United States)

    Spagnuolo, C. M.; Rapalini, A. E.; Astini, R. A.

    2008-05-01

    In the early Paleozoic western South America underwent a complex tectonic history that includes a more or less continuous active margin that witnessed the accretion and displacement of several terranes. In particular, many models have been proposed to account for the geologic evolution of the northwestern region of Argentina in the Lower Paleozoic, which range from a wholly ensialic evolution to the accretion of exotic and/or para- autochthonous terranes. During the last three years a systematic paleomagnetic study on Lower Paleozoic sedimentary and volcanic rocks from NW Argentina have yielded a Late Cambrian paleomagnetic pole for the Eastern Cordillera (23° S 65° W, Campanario Fm.), an Early to Middle Ordovician pole for the Famatina volcanic arc (28° S 68° W, Cerro Morado and Los Molles Fms.) and a Permian one in the same locality. A clockwise rotation around 35° is found for both Lower Paleozoic units, while the Permian one is coincident with the apparent polar wander path of Gondwana. The Early Paleozoic results are virtually identical to others found several years ago in the Eastern Puna magmatic belt and in the same Famatina System. On the other hand, a counter-clockwise rotation has been reported for Early Paleozoic rocks exposed at different localities of the Antofalla block. Those results are reviewed together with the structural and geological information of the region in order to evaluate the feasibility of different tectonic models such as i) the opening and closure of a back-arc basin, ii) the collision or displacement of a para-autochthonous terrane, or iii) the development of systematic block rotations associated to oblique subduction or scape tectonics.

  5. 30 CFR 56.15020 - Life jackets and belts.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Life jackets and belts. 56.15020 Section 56.15020 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 56.15020 Life jackets and belts. Life jackets or belts shall be worn where there is danger from...

  6. 30 CFR 57.15020 - Life jackets and belts.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Life jackets and belts. 57.15020 Section 57.15020 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Protection Surface Only § 57.15020 Life jackets and belts. Life jackets or belts shall be worn where there is...

  7. 14 CFR 125.211 - Seat and safety belts.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Seat and safety belts. 125.211 Section 125... Requirements § 125.211 Seat and safety belts. (a) No person may operate an airplane unless there are available... share one approved safety belt and two persons occupying a multiple lounge or divan seat may share...

  8. 49 CFR 392.16 - Use of seat belts.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Use of seat belts. 392.16 Section 392.16... VEHICLES Driving of Commercial Motor Vehicles § 392.16 Use of seat belts. A commercial motor vehicle which has a seat belt assembly installed at the driver's seat shall not be driven unless the driver...

  9. Observed seat belt use in Kumasi Metropolis, Ghana.

    Science.gov (United States)

    Afukaar, Francis K; Damsere-Derry, James; Ackaah, Williams

    2010-01-01

    We conducted an observational survey of seat belt use to determine the use rate of drivers and front-right passengers of vehicles in Kumasi, Ghana. Unobtrusive observations of seat belt use were made at 41 locations composed of signalized intersections and roundabouts where vehicles come to a halt or slow down considerably. The overall driver seat belt use rate was 17.6% compared to 4.9% for front-right passengers. Driver belt use was 33.2% for private cars, 9.0% for taxis, 8.3% for minibus (trotro), 13.1% for large buses and 9.7% for trucks. Overall seat belt use was higher for female drivers than for male drivers (44.8% versus 16.4%, p seat belt use rate increased with age. Passengers belted more often if drivers were belted, but about three-quarters of male passengers and 70-80% of female passengers were unbelted even when drivers were belted. In conclusion, the seat belt use rate was generally low in Kumasi, Ghana, and it is a function of occupant seating position, gender, vehicle type and usage, age group, and location setting. The results provide important preliminary data about seat belt use, particularly among male drivers and commercial vehicle occupant population. The study also suggests the need to develop effective strategies and programs that address low seat belt use in Ghana.

  10. School Buses & Seat Belts: A Discussion.

    Science.gov (United States)

    Alaska State Dept. of Education, Juneau.

    Safety belts are not installed in school buses for several reasons. School buses are constructed differently from automobiles in terms of (1) the locations of doors and instrument panels relative to passengers, (2) outer construction, (3) seat design and padding, and (4) visibility on the road. Under current regulations, bus seats are constructed…

  11. Design aspects of multiple driven belt conveyors

    NARCIS (Netherlands)

    Nuttall, A.J.G.

    2007-01-01

    Worldwide belt conveyors are used to transport a great variety of bulk solid materials. The desire to carry higher tonnages over longer distances and more diverse routes, while keeping exploitation costs as low as possible, has fuelled many technological advances. An interesting development in the r

  12. Design aspects of multiple driven belt conveyors

    NARCIS (Netherlands)

    Nuttall, A.J.G.

    2007-01-01

    Worldwide belt conveyors are used to transport a great variety of bulk solid materials. The desire to carry higher tonnages over longer distances and more diverse routes, while keeping exploitation costs as low as possible, has fuelled many technological advances. An interesting development in the

  13. Is the Cameron River greenstone belt allochthonous?

    Science.gov (United States)

    Kusky, T. M.

    1986-01-01

    Many tectonic models for the Slave Province, N.W.T., Canada, and for Archean granite - greenstone terranes in general, are implicitly dependent on the assumption that greenstone belt lithologies rest unconformably upon older gneissic basement. Other models require originally large separations between gneissic terranes and greenstone belts. A key question relating to the tectonics of greenstone belts is therefore the original spatial relationship between the volcanic assemblages and presumed-basement gneisses, and how this relationship has been modified by subsequent deformation. What remains unclear in these examples is the significance of the so-called later faulting of the greenstone - gneiss contacts. Where unconformities between gneisses and overlying sediments are indisputable, such as at Point Lake, the significance of faults which occur below the base of the volcanic succession also needs to be evaluated. As part of an on-going investigation aimed at answering these and other questions, the extremely well-exposed Cameron River Greenstone Belt and the Sleepy Dragon Metamorphic Complex in the vicinity of Webb Lake and Sleepy Dragon Lake was mapped.

  14. Pregnancy: Should I Use a Seat Belt?

    Science.gov (United States)

    ... always wear your seat belt even if your car has air bags.Where should I sit if I’m a ... editorial staff Categories: Family Health, Pregnancy and ChildbirthTags: air bag, auto accident, automobile safety, car accident, car safety, fetal injury, patient ...

  15. The thrust belts of Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, F.C.

    1993-08-01

    Most of the Basin and Range physiographic province of western North America is now believed to be part of the overthrust. The more obvious overthrust belt along the eastern edge of the Basin and Range Province is named the Sevier orogenic belt, where older rocks are observed thrust onto younger rocks. More detailed surface geological mapping, plus deep multiple-fold geophysical work and many oil and gas wildcat wells, have confirmed an east-vergent shortened and stacked sequence is present in many places in the Basin and Range. This western compressive deformed area in east central Nevada is now named the Elko orogenic belt by the U.S. Geological Survey. This older compressed Elko orogenic belt started forming approximately 250 m.y. ago when the North American plate started to move west as the Pangaea supercontinent started to fragment. The North American plate moved west under the sediments of the Miogeocline that were also moving west. Surface-formed highlands and oceanic island arcs on the west edge of the North American plate restricted the westward movement of the sediments in the Miogeocline, causing east-vergent ramp thrusts to form above the westward-moving North American plate. The flat, eastward-up-cutting thrust assemblages moved on the detachment surfaces.

  16. Belts and Chains. FOS: Fundamentals of Service.

    Science.gov (United States)

    John Deere Co., Moline, IL.

    This manual on belts and chain drives is one of a series of power mechanics texts and visual aids on theory, of operation, diagnosis, and repair of automotive and off-the-road agricultural and construction equipment. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and…

  17. Belts and Chains. FOS: Fundamentals of Service.

    Science.gov (United States)

    John Deere Co., Moline, IL.

    This manual on belts and chain drives is one of a series of power mechanics texts and visual aids on theory, of operation, diagnosis, and repair of automotive and off-the-road agricultural and construction equipment. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and…

  18. Economic Valuation of Green Belt: Focusing on the Conservation Value of Green Belt in Greater Seoul

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon Koo [Seoul National University, Seoul (Korea); Shin, Young Cheol [Daejin University, Pochon (Korea)

    2000-09-01

    The purpose of this paper is to measure the benefits of conservation of the green belt in the Greater Seoul area by CVM using dichotomous choice with a follow-up elicitation method. According to the government's plan, part of the green belt in the Greater Seoul area is to be freed from green belt designation. The mean willingness-to-pay(WTP) to conserve the green belt in the current state turns out to be about 7,430 won(95% confidence interval 6,220{approx}8,640 won) per household, which amounts to 308 billion won per year for entire population of Seoul. This WTP figure is found to be significantly influenced by level of education, sex, and the variables related to the perception and attitudes of respondents. (author). 26 refs., 3 tabs.

  19. Belt fires and mine escape problems

    Energy Technology Data Exchange (ETDEWEB)

    Kovac, J.G.; Lazzara, C.P. [Bureau of Mines, Pittsburgh, PA (United States); Kravitz, J.H.

    1996-12-31

    A conveyor belt fire in an underground coal mine is a serious threat to life and property. About 30% of the reportable underground coal mine fires from 1988 through 1992 occurred in belt entries. In one instance, a fire started in the drive area of a belt line, spread rapidly, and resulted in seating of the entire mine. Large-scale studies conducted by the U.S. Bureau of Mines in an aboveground fire gallery at Lake Lynn Laboratory clearly show the hazards of conveyor belt fires. Mine conveyor belt formulations which passed the current Federal acceptance test for fire-resistant betting were completely consumed by propagating fires or propagated flame, with flame spread rates ranging from 0.3 to 9 m/min. High downstream temperatures and large quantities of smoke and toxic gases, such as carbon monoxide, were generated as the belting burned. The smoke and gases can be spread by the mine`s ventilation system and can create significant problems for miners in the process of evacuation, such as reduction in visibility and incapacitation. In the aftermath of a belt fire, the atmosphere inside of the mine can become smoke filled or unbreathable, forcing miners to evacuate while wearing Self-Contained Self-Rescuers (SCSR`s), Sometimes there is confusion about how to regard the rated duration of an MSHA/NIOSH-approved 60-min. SCSR, especially when an SCSR is used in a way which takes it outside of the test conditions under which it was approved. As examples, for a mine escape that takes a miner from the deepest point of penetration in the mine to the surface: How long will a 60-min. SCSR actually last? and How many SCSR`s will a miner need? To answer these kinds of questions, in-mine data being gathered on escape times, distance and heart rates using miners escaping on foot and under oxygen. A model will be developed and validated which predicts how much oxygen is actually needed for a mine escape, and compares oxygen consumption bare faced versus wearing an SCSR.

  20. Imaging Jupiter Radiation Belts At Low Frequencies

    Science.gov (United States)

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

    2014-04-01

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

  1. GRANITE CLASSIFICATION,FORMATION, EVOLUTION AND MINERALIZATION IN THE WUGONG SHAN METALLOGENIC BELT%武功山成矿带花岗岩的分类、形成、演化与成矿

    Institute of Scientific and Technical Information of China (English)

    杨子江

    1986-01-01

    @@ 本文对武功山成矿带中的22个花岗岩体的化学成分进行了分析,并编制了与其相应的朱为方氏Q-A-P投影图,从而得知:该带花岗岩主要是闪长花岗岩、二长花岗岩、碱性长石花岗岩,最广泛的是铝过饱和系列白云母-黑云母-长石、石英矿物组合(简称白云母-黑云母组合),长石牌号低,An的百分数为0-15%.由早到晚,岩石从黑云母闪长花岗岩→含黑云母、白云母二长花岗岩→二云母二长花岗岩→二云母碱性长石花岗岩→白云母碱性长石花岗岩.花岗岩是花岗岩化的产物.成矿作用与花岗岩化作用两者具相同的地质环境,矿床与花岗岩两者的形成作用也相似.

  2. 攀西铁矿成矿带地质矿产特征及找矿方向%Geology and exploration of the iron metallogenic belts in the PanzhihuaXichang zone, southwestern Sichuan

    Institute of Scientific and Technical Information of China (English)

    王子正; 范文玉; 高建华; 林明; 周邦国

    2012-01-01

    Four areas of ore prospecting for the iron ore deposits in the Panzhihua-Xichang zone, southwestern Sichuan are delineated according to regional geology, distribution of the ore deposits, geophysical properties and remote-sensing interpretation. They are the Lugu (in Mianning) -Dengxiangying (in Xide) iron-rich ore prospecting area, Kuangshanliangzi-Niuchang (in Yanyuan) iron-rich ore prospecting area, Taihe-Panzhihua vanadio-titanomagnetite ore prospecting area, and Xinglong (in Dechang)-Longquan (in Huili) iron ore prospecting area. The key types of iron deposits for the further exploration should be concentrated in the late-magmatic differentiational iron deposits and volcanic-sedimentary-metaraorphic iron deposits.%本文通过对攀西地区区域地质、区域矿产特征的分析,综合地球物理、遥感解译资料,共划分出4个找矿远景区:冕宁泸沽-喜德登相营富铁矿找矿远景区、盐源矿山梁子-牛厂富铁矿找矿远景区、太和-攀枝花钒钛磁铁矿远景区、西昌德昌兴隆-会理龙泉铁矿远景区.指出远景区内岩浆晚期分异型铁矿床、火山沉积变质型铁矿床等为主攻矿种.

  3. International survey of seat belt use exemptions.

    Science.gov (United States)

    Weiss, H; Sirin, H; Levine, J A; Sauber, E

    2006-08-01

    Substantial evidence of seatbelt efficacy has been shown by several studies, and it is widely recommended that motor vehicle occupants use properly fitted seat belts. However, some (but a heretofore unknown number of) countries with national seat belt laws permit various exemptions which may lower use rates. The aim of this study was to survey the variety of exemptions to national seat belt laws. This investigation relied on identifying respondents from national traffic safety agencies, other governmental and non-governmental organizations, Internet searches, personal contacts, and other sources. Questionnaires were deployed through a web based survey supplemented by email and postal versions. Responses were received from 30 countries of which 28 (93.7%) had a national seat belt law. About two thirds (63.7%) of the 28 national laws applied to both front and back seat passengers. The leading exemption types included vehicles made before a certain year (n = 13), antique vehicles (n = 12), military vehicles (n = 11), buses (n = 9), and emergency vehicles (n = 8). Most responding countries reported one or more specific categories of individuals as exempt including those with medical exemptions (n = 20), taxi drivers (n = 11), police (n = 9), emergency medical personnel (n = 8), physically disabled people (n = 6), and pregnant women (n = 6). Out of 26 responses to the question regarding current level of enforcement, 42.3% felt enforcement was "very good or good" and 57.7% characterized it as "fair or poor". This study represents one of the largest international traffic law surveys reported. Most national seatbelt laws offer perilous exemptions to a broad array of vehicle types and road user groups. These findings, coupled with concern over the level of enforcement in the majority of countries surveyed, suggest that international road safety efforts have a long way to go to improve coverage and enforcement of national seat belt laws.

  4. The Palaeozoic strata near Moeche in Galicia, NW Spain

    NARCIS (Netherlands)

    Meer Mohr, van der C.G.

    1976-01-01

    Coral fragments, crinoidal debris and foraminifers found in limestone beds near Moeche (Galicia) are evidence of a Devonian-Silurian age for the strata in the greenschist facies belt around Cabo Ortegal, hitherto considered on the Spanish 1:200,000 map-La Coruña Hoja 1 (IGME), to be Precambrian in a

  5. China belting up or down? Seat belt wearing trends in Nanjing and Zhoushan.

    Science.gov (United States)

    Routley, Virginia; Ozanne-Smith, Joan; Li, Dan; Yu, Min; Wang, Jianyue; Zhang, Junhe; Tong, Zhendong; Wu, Ming; Wang, Peihua; Qin, Yu

    2008-11-01

    National seat belt wearing legislation became effective in China May 2004 and associated provincial and city regulations followed. Despite rapid motorisation seat belt studies in China have been scarce. Patterns and trends in urban seat belt wearing were observed for all driver, front and rear seating positions over the years 2005-2007 in two eastern cities Nanjing (Jiangsu Province) and Zhoushan (Zhejiang Province). There were 35,256 vehicles observed in Nanjing, 20,939 in Zhoushan and 95,933 occupants overall. Males dominated all seating positions, especially drivers. Seat belt wearing overall was significantly higher for drivers (49.9% Nanjing, 47.4% Zhoushan) than for front seat passengers (9.1% Nanjing, 1.0% Zhoushan) and virtually nonexistent for rear passengers (0.5% Nanjing, 0.2% Zhoushan). Generally levels declined significantly from year to year (drivers Nanjing 66.7%, 47.7%, 38.6%; Zhoushan 57.4%, 57.9%, 30.6%; front passengers Nanjing 19.2%, 6.6%, 3.2%). Zhoushan wearing did not initially decline, 2006 observations coinciding with anticipation of provincial regulations (July 2006). Observations revealed an absence of child restraints. Pretend wearing/belt tampering was observed almost exclusively in taxi drivers (14.2% of Nanjing taxi drivers, 11.3% of Zhoushan's). Awareness of and attitudes to urban seat belt laws should be investigated, appropriate countermeasures developed and enforcement reassessed.

  6. The Gould Belt, the de Vaucouleurs-Dolidze Belt, and the Orion Arm

    CERN Document Server

    Bobylev, V V

    2014-01-01

    Based on masers with measured trigonometric parallaxes, we have redetermined the spatial orientation parameters of the Local (Orion) arm. Using 23 sources (the Gould Belt objects were excluded), we have found that their spatial distribution can be approximated by a very narrow ellipsoid elongated in the direction L_1=77.1+/-2.9^o whose symmetry plane is inclined to the Galactic plane at an angle of 5.6+/-0.2^o. The longitude of the ascending node of the symmetry plane is l_\\Omega=70+/-3^o. A new estimate for the pitch angle of the Local spiral arm has been obtained by an independent method: i=12.9+/-2.9^o. Previously, a belt of young B stars, the de Vaucouleurs.Dolidze belt, was pointed out on the celestial sphere with parameters close to such an orientation. We have refined the spatial orientation parameters of this belt based on a homogeneous sample of protostars. The de Vaucouleurs.Dolidze belt can be identified with the Local arm, with the belt proper as a continuous band on the celestial sphere like the ...

  7. VERO cells harbor a poly-ADP-ribose belt partnering their epithelial adhesion belt

    Directory of Open Access Journals (Sweden)

    Laura Lafon-Hughes

    2014-10-01

    Full Text Available Poly-ADP-ribose (PAR is a polymer of up to 400 ADP-ribose units synthesized by poly-ADP-ribose-polymerases (PARPs and degraded by poly-ADP-ribose-glycohydrolase (PARG. Nuclear PAR modulates chromatin compaction, affecting nuclear functions (gene expression, DNA repair. Diverse defined PARP cytoplasmic allocation patterns contrast with the yet still imprecise PAR distribution and still unclear functions. Based on previous evidence from other models, we hypothesized that PAR could be present in epithelial cells where cadherin-based adherens junctions are linked with the actin cytoskeleton (constituting the adhesion belt. In the present work, we have examined through immunofluorescence and confocal microscopy, the subcellular localization of PAR in an epithelial monkey kidney cell line (VERO. PAR was distinguished colocalizing with actin and vinculin in the epithelial belt, a location that has not been previously reported. Actin filaments disruption with cytochalasin D was paralleled by PAR belt disruption. Conversely, PARP inhibitors 3-aminobenzamide, PJ34 or XAV 939, affected PAR belt synthesis, actin distribution, cell shape and adhesion. Extracellular calcium chelation displayed similar effects. Our results demonstrate the existence of PAR in a novel subcellular localization. An initial interpretation of all the available evidence points towards TNKS-1 as the most probable PAR belt architect, although TNKS-2 involvement cannot be discarded. Forthcoming research will test this hypothesis as well as explore the existence of the PAR belt in other epithelial cells and deepen into its functional implications.

  8. Assessing Soil Quality in Areas Affected by Sulfide Mining. Application to Soils in the Iberian Pyrite Belt (SW Spain

    Directory of Open Access Journals (Sweden)

    Isabel González

    2011-11-01

    Full Text Available The characterization, evaluation and remediation of polluted soils is one of the present environmental challenges to be addressed in the coming years. The origin of trace elements in soils can be either geogenic or anthropogenic, but only the latter is interesting from a legal point of view. The hazard of the pollutants in the soils not only depends on their total concentration, but particularly on their availability. The mobility of the trace elements depends on their speciation, and it is also affected by several soil parameters. Mining activity is one of the most important anthropogenic causes of soil pollution. As a case study, this work is focused in the Riotinto mining area (Iberian Pyrite Belt, IPB, SW Spain. The IPB is one of the most important metallogenic provinces in the world and it has been exploited for thousands of years. The disposal of mining residues has produced important sources of contamination by trace elements and acidic waters affecting soils and rivers. In addition to these problems, the closure of mines in the Pyrite Belt at the end of the 20th Century has led to a great loss of employment, which has caused the development of an intensive agriculture of citrus fruits as a new source of income. The intensive growing of citrus fruits and the traditional subsistence agriculture have been developed surrounding the mining areas and on floodplains near to mining sites. The level of soil pollution has not been taken into account in these cases, nor has its impact on the health of the inhabitants of these areas. Therefore, it is of great interest to study the current state of the cultivated soils and the sources and types of contaminants derived from mining activity in order to program its decontamination, where appropriate, according to legislation. In order to know the present and future hazard posed by the soils chemical and mineralogical speciation has been carried out, given that the availability of a metal depends on the

  9. Experimental deformation partitioning in obliquely converging orogens with lateral variations of basal décollement rheology: Inferences for NW Zagros, Iran

    Science.gov (United States)

    Sadeghi, Shahriar; Storti, Fabrizio; Yassaghi, Ali; Nestola, Yago; Cavozzi, Cristian

    2016-12-01

    The rheology of décollement materials fundamentally constrains the kinematic evolution and tectonic architecture of orogenic belts. In this paper, we present the result of an experimental program designed for investigating, by sandbox analog modeling, the impact of the spatial distribution of décollement rheology underneath an inner carbonate platform-basin-outer carbonate platform paleogeographic architecture undergoing traspressional deformations. Our models indicate that viscous décollements at the base of both platforms favor the outward propagation of deformation, duplexing in the Inner Platform (that faces the wedge toe), and deep burial of basinal sediments. On the other hand, frictional rheologies favor internal shortening in the basin, strong uplift and limited burial. Application of experimental results to better constrain the late Cretaceous tectonic evolution of the NW Zagros is discussed.

  10. Broad belts of shear zones: The common form of surface rupture produced by the 28 June 1992 Landers, California, earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, A.M.; Cruikshank, K.M. [Geological Survey, Denver, CO (United States)]|[Purdue Univ., West Lafayette, IN (United States). Richard H. Jahns Engineering Geology Lab.; Fleming, R.W. [Geological Survey, Denver, CO (United States)

    1993-12-31

    Surface rupturing during the 28 June 1992, Landers, California earthquake, east of Los Angeles, accommodated right-lateral offsets up to about 6 m along segments of distinct, en echelon fault zones with a total length of about 80 km. The offsets were accommodated generally not by faults -- distinct slip surfaces -- but rather by shear zones, tabular bands of localized shearing. In long, straight stretches of fault zones at Landers the rupture is characterized by telescoping of shear zones and intensification of shearing: broad shear zones of mild shearing, containing narrow shear zones of more intense shearing, containing even-narrower shear zones of very intense shearing, which may contain a fault. Thus the ground ruptured across broad belts of shearing with subparallel walls, oriented NW. Each broad belt consists of a broad zone of mild shearing, extending across its entire width (50 to 200 m), and much narrower (a few m wide) shear zones that accommodate most of the offset of the belt and are portrayed by en echelon tension cracks. In response to right-lateral shearing, the slices of ground bounded by the tension cracks rotated in a clockwise sense, producing left lateral shearing, and the slices were forced against the walls of the shear zone, producing thrusting. Even narrower shear zones formed within the narrow shear zones, and some of these were faults. Although the narrower shear zones probably are indicators to right-lateral fault segments at depth, the surface rupturing during the earthquake is characterized not by faulting, but by zones of shearing at various scales. Furthermore, understanding of the formation of the shear zones may be critical to understanding of earthquake faulting because, where faulting is associated with the formation of a shear zone, the faulting occurs late in the development of the shear zone. The faulting occurs after a shear zone or a belt of shear zones forms.

  11. Re-Os dating of molybdenite from Tongchanggou Mo-polymetallic deposit in northwest Yunnan and its metallogenic environment%滇西北铜厂沟钼多金属矿床辉钼矿Re-Os同位素年龄及其成矿环境

    Institute of Scientific and Technical Information of China (English)

    李文昌; 余海军; 尹光侯; 曹晓民; 黄定柱; 董涛

    2012-01-01

    technique was applied, and six molybdenite samples were analyzed for Re-Os isotopic compositions, and the model ages obtained are from (82.34 ± 1.28) to (88.27 ± 1.23) Ma, with the isochron age being (85 ± 10) Ma. The result suggests that Mo mineralization occurred in Yanshanian period, during which Zhongza block and Yangtze landmass collided intensively and gradu- ally turned into post-collision stage. Because of the thickening of the crust, crustal melting or crustal-mantle melting resulted in the formation of S-type granite and granite porphyry, accompanied by molybdenum poly-metallic mineralization. The Re content of the molybdenite is 6 440\\~43 530 ng/g, suggesting that the metallo-genic material originated from a source mixed with crust and mantle components. Field investigation shows that concealed granite intrusions may exist in the depth, and mineralization was related to magmatic intrusion. Acid intrusions in the area extend from north to south and the belt passes through Yidun arc and enters the western margin of Yangtze landmass. In northwestern Yunnan, a number of large-middle molybdenum polymetallic deposits were formed in the belt accordingly; they are scattered from north to south, represented by Xiuwacu, Re-lin, Hongshan and Tongchanggou. The research on metallogenic background and ore prognosis is of great significance for ore exploration in this area.

  12. Origin of the Rubian carbonate-hosted magnesite deposit, Galicia, NW Spain: mineralogical, REE, fluid inclusion and isotope evidence

    Science.gov (United States)

    Kilias, Stephanos P.; Pozo, Manuel; Bustillo, Manuel; Stamatakis, Michael G.; Calvo, José P.

    2006-10-01

    The Rubian magnesite deposit (West Asturian—Leonese Zone, Iberian Variscan belt) is hosted by a 100-m-thick folded and metamorphosed Lower Cambrian carbonate/siliciclastic metasedimentary sequence—the Cándana Limestone Formation. It comprises upper (20-m thickness) and lower (17-m thickness) lens-shaped ore bodies separated by 55 m of slates and micaceous schists. The main (lower) magnesite ore body comprises a package of magnesite beds with dolomite-rich intercalations, sandwiched between slates and micaceous schists. In the upper ore body, the magnesite beds are thinner (centimetre scale mainly) and occur between slate beds. Mafic dolerite dykes intrude the mineralisation. The mineralisation passes eastwards into sequence of bedded dolostone (Buxan) and laminated to banded calcitic marble (Mao). These show significant Variscan extensional shearing or fold-related deformation, whereas neither Rubian dolomite nor magnesite show evidence of tectonic disturbance. This suggests that the dolomitisation and magnesite formation postdate the main Variscan deformation. In addition, the morphology of magnesite crystals and primary fluid inclusions indicate that magnesite is a neoformed hydrothermal mineral. Magnesite contains irregularly distributed dolomite inclusions (modified basinal brines that have reacted and equilibrated with intercalated siliciclastic rocks. Magnesite formation is genetically linked to regional hydrothermal dolomitisation associated with lithospheric delamination, late-Variscan high heat flow and extensional tectonics in the NW Iberian Belt. A comparison with genetic models for the Puebla de Lillo talc deposits suggests that the formation of hydrothermal replacive magnesite at Rubian resulted from a metasomatic column with magnesite forming at higher fluid/rock ratios than dolomite. In this study, magnesite generation took place via the local reaction of hydrothermal dolostone with the same hydrothermal fluids in very high permeability zones at

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

    Science.gov (United States)

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

    2016-06-17

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

  14. LOAD DISTRIBUTION ON DRUMS OF DOUBLE DRIVE BELT CONVEYOR

    Institute of Scientific and Technical Information of China (English)

    薛河; 苏清祖; 马胜利

    1999-01-01

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

  15. Persistence of Salmonella on egg conveyor belts is dependent on the belt type but not on the rdar morphotype.

    Science.gov (United States)

    Stocki, S L; Annett, C B; Sibley, C D; McLaws, M; Checkley, S L; Singh, N; Surette, M G; White, A P

    2007-11-01

    Commercial caged layer flocks in Alberta, Canada, are commonly monitored for Salmonella enterica serovar Enteritidis (SE) and S. enterica serovar Typhimurium (ST) by environmental sampling. In one recent case, a SE strain isolated from the egg conveyor belt was a source of persistent infection for the flock. This study was undertaken to examine Salmonella colonization on egg conveyor belts and to determine whether the rdar morphotype, a conserved physiology associated with aggregation and long-term survival, contributed to persistence. Four woven belts constructed of natural or nonnatural fibers and a 1-piece belt made of vinyl were tested with rdar-positive ST and SE strains and a rdar-negative ST DeltaagfD reference strain. The type of egg belt was the most important factor influencing Salmonella colonization and persistence. The vinyl belt, with the least surface area available for colonization, had the fewest Salmonella remaining after washing and disinfection, whereas the hemp-plastic belt, with the greatest surface area, had the most Salmonella remaining. Real-time gene expression indicated that the rdar morphotype was involved in colonizing the egg belt pieces; however, it was not essential for persistence. In addition, rdar-positive and rdar-negative strains were equally similarly to disinfection on the egg belt pieces. The results indicate that Salmonella can persist on a variety of egg belts by mechanisms other than the rdar morphotype, and that using egg conveyer belts with reduced surface area for bacterial colonization can lessen contamination problems.

  16. 郯庐断裂带(五河段)演化特征与矿化关系研究%Research on evolution and mineralization characteristics of Wuhe section of Tan-Lu fault belt

    Institute of Scientific and Technical Information of China (English)

    陈皓龙; 刘国生

    2014-01-01

    The study area is located in the southeast margin of North China Plate and close to the west side of the Tan‐Lu fault belt .It has the same tectonic background with Jiaodong gold belt ,and their metallogenic ge‐ological conditions and structure are very similar .Based on the previous researches on Jiaodong gold belt and its ore‐controlling rules as well as the metallogenic theory and the systematic geological survey ,and taking the fault structure of Zhuding‐Shimenshan fault as the focus of research ,the evolution of the Tan‐Lu fault belt is studied with the help of the disclosure of many existing quarries .It is pointed out that the Wuhe section of Tan‐Lu fault belt has gone through three major development stages :the first movement period corresponded to the Late Jurassic to Early Cretaceous ,characterized by left‐lateral strike‐slip ductile shear zone;the second movement period corresponded to the Early Cretaceous to Paleogene ,with brittle extensional normal faults ;and the third movement period corresponded to Neogene to now ,with squeeze thrusting faults .It is found that the control of NNE‐trending faults in this area during the extension period on the magmatic rocks ,miner‐alization and output and distribution of quartz veins containing ore is significant ,especially the strongly frac‐tured parts and multiple quartz veins filling parts of the faults are a good sign of prospecting ,w hich should be paid attention to in the future prospecting .%研究区位于华北板块东南缘,郯庐断裂带西侧近旁侧。本区与胶东金矿矿集区具有相同的大地构造背景,其成矿地质条件及结构非常类似。文章在总结前人对胶东矿集区断裂及其控矿规律的研究基础上,以成矿谱系理论为指导、以断裂构造研究为主线,借助现有多处采石场的揭露,在系统的野外地质调查基础上,对郯庐断裂带(朱顶‐石门山断裂)的演化进行研

  17. Potential for Great Thrust Earthquakes in NE Colombia & NW Venezuela

    Science.gov (United States)

    Bilham, R. G.; Mencin, D.

    2013-05-01

    Sixty-five percent of the ≈19 mm/yr eastward velocity of the Caribbean Plate north of Aruba and the Guajira peninsula relative to the South American plate is accommodated by dextral slip on the Bocono Fault system in NW Venezuela at 12±1 mm/yr, the remaining ~3 mm/yr of shear apparently distributed to the NW of the fault (Perez et al., 2011). The N40E strike of the Bocono fault system, however, requires that 10.6±1 mm/yr of convergence should accompany this partitioned dextral shear, but GPS measurements reveal that less than 25% of this convergence occurs across the Venezuelan Andes. The remaining 6-8 mm of convergence is presumably accommodated by incipient subduction between the Bocono fault and a trench 300 km NW of the northern coast of Colombia. Hence NW Venezuela and NE Colombia may occasionally host great earthquakes. Our current poor understanding of the geometry of the plate interface permits the plate to be locked 300 km down-dip and possibly 600 km along-strike, and if the plate slips in 10 m ruptures it could do so every 1200 years in a M~9 earthquake. No great earthquake has occurred since 1492, since when ~4 m of potential slip has developed, but should slip occur on just 10% of the hypothesized décollement (100x150 km) it could do so now in an Mw=8.2 earthquake. In that a potential Mw>8 earthquake poses a future seismic and tsunami threat to the Caribbean it is important to examine whether great earthquakes have occurred previously near the NW Venezuela coast. It is possible that creep accommodates the entire convergence signal, since there is no suggestion from microseismicity for an abrupt locked-to-sliding transition, as, for example, signifies its location in the Himalaya. An alternative measure of future potential seismic energy release is to identify the locus and rate of present-day strain contraction. To this end, Venezuelan, Colombian and US (CU and UNAVCO) investigators are installing an array of more than a dozen continuous operating

  18. Ionic composition of the earth's radiation belts

    Science.gov (United States)

    Spjeldvik, W. N.

    1983-01-01

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

  19. HP metamorphic belt of the western Alps

    Institute of Scientific and Technical Information of China (English)

    RobertoCompagnoni

    2003-01-01

    The understanding of the subduction-related processes benefited by the studies of the high-pressure (HP) meta-morphic rocks from the western Alps. The most stimu-lating information was obtained from the inner part of the western Alpine belt, where most tectonic units show an early Alpine eclogite-facies recrystallisation. This is especially true for the Austroalpine Sesia Zone and the Penninic Dora-Maira massif. From the Sesia zone,which consists of a wide spectrum of continental crust lithologies recrystallised to quartz-eclogite-facies min-eral assemblages, the first finding of a jadeite-bearingmeta-granitoid has been described, supporting evidencethat even continental crust may subduct into the mantle.From the Dora-Maira massif the first occurrence of regional metamorphic coesite has been reported, open-ing the new fertile field of the ultrahigh-pressure meta-morphism (UHPM), which is now becoming the rule in the collisional orogenic belts.

  20. 晋东北地区银矿床类型及成矿机制%Silver Ore Deposit Type and Its Metallogenic Mechanism in Northeast Shanxi

    Institute of Scientific and Technical Information of China (English)

    赵英福; 张连营; 李兆龙

    2011-01-01

    Research on silver ore deposit type and geological characteristics of the ore deposit shows that the main genetic types of silver deposits in northeast Shanxi are medium to lower temperature hydrothermal deposit type associated with volcanic process including quartz-vein type silver deposit, volcanic type silver deposit, cryptoexplosion breccia type silver deposit), and contact metasomatism skarn type silver deposit, stratabond silver and manganese ore deposit including oxidation leaching type manganese and silver deposit and iron-manganese stain silver and manganese deposit. The major metallogenic period is Yanshanian. A series of silver deposits were formed through volcanic to sub-volcanic hydrothermal process and oxidation and leaching process on the earth surface.%银矿床类型和矿床地质特征研究表明,晋东北地区银矿王要成因类型为与火山作用有关的中低温热液银矿床(包括石英脉型银矿、火山岩型银矿、(隐)爆破角砾岩型银矿),其次为接触交代矽卡岩型银矿、层控银锰矿床(包括氧化淋滤型锰银矿和铁锰帽型银锰矿).银的主要成矿期为燕山期.在沉积作用、火山一次火山热液作用和地表氧化淋滤作用条件下形成了系列银矿床.

  1. Zircon U-Pb dating of Maherabad porphyry copper-gold prospect area: evidence for a late Eocene porphyry-related metallogenic epoch in east of Iran

    Directory of Open Access Journals (Sweden)

    Azadeh Malekzadeh Shafaroudi

    2011-04-01

    Full Text Available Eastern Iran has great potential for porphyry copper deposits, as a result of its past subduction zone tectonic setting that lead to extensive alkaline to calc-alkaline magmatic activity in Tertiary time. Maherabad is the first porphyry Cu-Au prospecting area which is discovered in eastern Iran. This is related to a succession o f monzonitic to dioritic porphyries stocks that were emplaced within volcanic rocks. Monzonitic porphyries have basic role in mineralization. Hydrothermal alteration zones are well developed including potassic, sericitic-potassic, quartz-sericite-carbonate-pyrite, quartz-carbonate-pyrite, silicified-propylitic, propylitic, carbonate and silicified zones. Mineralization occurs as Disseminated, stockwork and hydrothermal breccia. Based on early stage of exploration, Cu is between 179- 6830 ppm (ave. 3200 ppm and Au is up to 1000 ppb (ave. 570 ppb. This prospect is gold- rich porphyry copper deposit. Laser-ablation U-Pb dating of two samples from ore-related intrusive rocks indicate that these two monzonitic porphyries crystallized at 39.0 ± 0.8 Ma to 38.2 ± 0.8 Ma, within a short time span of less than ca. 1 Ma during the middle Eocene. This provides the first precise ages for metallogenic episode of porphyry-type mineralization. Also, the initial 87Sr/86Sr and (143Nd/144Ndi was recalculated to an age of 39 Ma. Initial 87Sr/86Sr ratios for monzonitic rocks are 0.7047-0.7048. The (143Nd/144Ndi isotope composition are 0.512694-0.512713. Initial ε Nd isotope values 1.45-1.81. Based on isotopic data the magma had originated beyond the continental crust. The study will be used for tectonic-magmatic setting and evolution of eastern Iran. Keywords: Lut block, Middle Eocene, Zircon, Geochronology, Laser ablation ICP-MS,

  2. Fluid evolution in H2O-CO2-NaCl system and metallogenic analysis of the Surian metamorphic complex, Bavanat Cu deposit, Southwest Iran

    Science.gov (United States)

    Asadi, Sina; Moore, Farid

    2016-07-01

    The Bavanat Cu deposit occurs as veins controlled by a NE-trending structure within the Permo-Triassic Surian metamorphic complex (SMC), southwest of Iran. The SMC rocks exposed in the area have undergone greenschist-facies metamorphism. The ore-forming process can be divided into early, middle, and late stages, represented by, respectively, pyrite-quartz, polymetallic sulfide-quartz, and late-stage barren quartz veins. Systematic studies of fluid inclusions (FIs) in the quartz veins found four types: aqueous, mixed aqueous-carbonic, carbonic, and multiphase-bearing inclusions. The FIs of early, middle and late-stages are mainly homogenized at temperatures of 335-417 °C, 230-380 °C, and 190-227 °C, with salinities of 1.1-6.7, 2.9-36.6, and 0.8-2.6 wt.% NaCl equivalent, respectively. The main stage of Cu mineralization is related to the middle-stage, where FIs show evidence of fluid immiscibility. The metal precipitation resulted from a decrease in copper solubility during the fluid immiscibility, cooling, crystallization of multiphase-bearing inclusions, and a small increase in pH. Laser Raman spectroscopy and FIs evidences indicate that the metallogenic system evolved from metamorphic CO2 (+CH4)-rich, relatively high fO2 (10-25 to 10-29 bars) to CO2-poor and relatively low fO2 (10-31 to 10-34 bars). Muscovite from the middle-stage veins yields 40Ar/39Ar plateau age of 195.2 ± 1.0 Ma, suggesting that the Cu mineralization at Bavanat formed in the Early Jurassic coeval with the retrograde metamorphic events during the post-early Cimmerian orogeny.

  3. Fluid evolution in H2O-CO2-NaCl system and metallogenic analysis of the Surian metamorphic complex, Bavanat Cu deposit, Southwest Iran

    Science.gov (United States)

    Asadi, Sina; Moore, Farid

    2017-02-01

    The Bavanat Cu deposit occurs as veins controlled by a NE-trending structure within the Permo-Triassic Surian metamorphic complex (SMC), southwest of Iran. The SMC rocks exposed in the area have undergone greenschist-facies metamorphism. The ore-forming process can be divided into early, middle, and late stages, represented by, respectively, pyrite-quartz, polymetallic sulfide-quartz, and late-stage barren quartz veins. Systematic studies of fluid inclusions (FIs) in the quartz veins found four types: aqueous, mixed aqueous-carbonic, carbonic, and multiphase-bearing inclusions. The FIs of early, middle and late-stages are mainly homogenized at temperatures of 335-417 °C, 230-380 °C, and 190-227 °C, with salinities of 1.1-6.7, 2.9-36.6, and 0.8-2.6 wt.% NaCl equivalent, respectively. The main stage of Cu mineralization is related to the middle-stage, where FIs show evidence of fluid immiscibility. The metal precipitation resulted from a decrease in copper solubility during the fluid immiscibility, cooling, crystallization of multiphase-bearing inclusions, and a small increase in pH. Laser Raman spectroscopy and FIs evidences indicate that the metallogenic system evolved from metamorphic CO2 (+CH4)-rich, relatively high fO2 (10-25 to 10-29 bars) to CO2-poor and relatively low fO2 (10-31 to 10-34 bars). Muscovite from the middle-stage veins yields 40Ar/39Ar plateau age of 195.2 ± 1.0 Ma, suggesting that the Cu mineralization at Bavanat formed in the Early Jurassic coeval with the retrograde metamorphic events during the post-early Cimmerian orogeny.

  4. Orogen-scale L tectonite domain in the Tongbai orogenic belt, central China: Geological setting and origin

    Science.gov (United States)

    Liu, Huan; Lin, Shoufa; Song, Chuanzhong

    2017-01-01

    L tectonite is well developed and widely distributed in the Tongbai orogenic belt in central China. The orogenic belt as a whole has an antiformal geometry and the hinge of the antiform is subhorizontal and trends NW-SE. The L tectonite occurs in the core of the antiform, in a zone that is 10-30 km wide and over 100 km long. Lineations in the L tectonite are sub-horizontal, parallel to the hinge of the antiform. Sheath folds are also well developed associated with the L tectonite, with the hinges parallel to the lineations. Migmatite occurs in the core and structurally below the L tectonite and has a gradational relationship with the L tectonite. The domain of L tectonite is bounded by three ductile shear zones, on the north, at the top and on the south, respectively. Well-developed shear sense indicators indicate that the southern, the overlying and the northern shear zones have a dextral, top-to-NW and sinistral sense of shear, respectively. These geometrical and kinematic data indicate that the three shear zones are likely part of a single shear zone that wraps around the L-tectonite domain. The L-tectonite zone in the core moves southeast relative to the hanging wall. The development of the tectonite is interpreted to be a result of this special geometry and kinematics and reflects a post-collisional orogen-parallel extension synchronous with migmatization and the continuing convergence between the Yangtze Block and the North China Block in the Early Cretaceous.

  5. Alien Asteroid Belt Compared to our Own

    Science.gov (United States)

    2005-01-01

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

  6. Metaheuristic Technique for Finding Earthquake Locations in NW Himalayan Region

    Science.gov (United States)

    Yadav, Anupam; Deep, Kusum; Kumar, Sushil; Sushil, Rama

    In this article, we have used a new metaheuristic technique particle swarm optimization (PSO) for development of the earthquake location models. Two models of different crustal structures has been taken based on the arbitrary tardiness structure that defines the heterogeneity of the earth’s crust. The problem of earthquake location is modeled as a least square function of travel times and solved by using the randomized search algorithm PSO. We have solved the problem by using an advanced version of PSOs. A real life data of earthquake in the NW Himalayan region has been taken for testing these developed models. The new locations are better than the existing results.

  7. TREPOSTOME BRYOZOANS FROM THE LOWER - MIDDLE DEVONIAN OF NW SPAIN

    Directory of Open Access Journals (Sweden)

    ANDREJ ERNST

    2010-11-01

    Full Text Available The present paper presents descriptions of 11 trepostome bryozoan species from the material deposited at the Geological Centrum Göttingen, Germany, and Nationaal Natuurhistorisch Museum (Naturalis, Leiden, Netherlands. The studied material comes from the Lower to Middle Devonian (Emsian-Eifelian deposits of different localities in Cantabrian Mountains, NW Spain. Three species are new: Leptotrypella maculata n. sp., Anomalotoechus tabulatus n. sp. and Eifelipora tenuis n. sp. The genus Mongoloclema is reported for the first time from the Devonian of Europe. The described fauna displays palaeobiogeographic relations to the Lower Devonian (Pragian of Bohemia and to the Middle Devonian of Kazakhstan and Michigan (USA. 

  8. The atmospheric implications of radiation belt remediation

    Directory of Open Access Journals (Sweden)

    C. J. Rodger

    2006-08-01

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

  9. Cu-Mo-Au mineralization in Qarachilar area, Qaradagh batholith (NW Iran): Fluid inclusion and stable isotope studies and Re-Os dating

    Science.gov (United States)

    Simmonds, Vartan; Moazzen, Mohssen

    2015-04-01

    The Qaradagh batholith is located in NW Iran, neighboring the Meghri-Ordubad granitoid in southern Armenia. This magmatic complex is emplaced in the northwestern part of the Urumieh-Dokhtar magmatic arc, which formed through north-eastward subduction of Neo-Tethyan oceanic crust beneath the central Iranian domain in the late-Mesozoic and early-Cenozoic and hosts most of the porphyry copper deposits and prospects in Iran, such as Sarcheshmeh and Sungun. The Qaradagh batholith is comprised of Eocene-Oligocene intrusive rocks occurring as multi-episode stocks, where the dominant rock type is granodiorite. Hydrothermal alterations have also occurred in these rocks including potassic, phyllic-sericitic, argillic and propylitic alterations and silicification. These alterations are accompanied by vein-type and disseminated Cu, Mo and Au mineralization. The Qarachilar area is located in the central part of the Qaradagh batholith, which hosts mono-mineralic and quartz-sulfide veins and veinlets (several mm to hydrothermal aqueous fluids have most likely experienced boiling and also mixed with low temperature and low salinity superficial fluids. Occurrence of boiling is also supported by the coexistence of liquid-rich and vapor-rich 2-phase inclusions as well as multi-phase halite-bearing inclusions which homogenize in a similar range of TH. The calculated minimum pressure at the time of entrapment is estimated about 50 to 120 bar, which is equal to the hydrostatic depth of 500-1100 m. Stable isotope studies of O, H and S on the quartz and sulfide samples taken from quartz-sulfide veins-veinlets reveal a magmatic origin for the ore-bearing fluid and its sulfur content. The δ18O values for quartz and fluid are about 11.13-12.47 ‰ and 5.78-6.89 ‰ (SMOW), respectively, the δD values are about -93 and -50 ‰ and the δ34S values of sulfide minerals are about -1.37-0.49‰ (VCDT). Re-Os model ages calculated for molybdenite samples range between 25.19±0.19 and 31.22±0

  10. Oblique half-graben inversion of the Mesozoic Neuquén Rift in the Malargüe Fold and Thrust Belt, Mendoza, Argentina: New insights from analogue models

    Science.gov (United States)

    Yagupsky, Daniel L.; Cristallini, Ernesto O.; Fantín, Julián; Valcarce, Gonzalo Zamora; Bottesi, Germán; Varadé, Roberto

    2008-07-01

    The Malargüe fold and thrust belt, located in the Andean mountains between 34°S and 36°30'S, formed in response to contraction during Cenozoic times. Its structural style and geometry was controlled by the Mesozoic rift system that formed the Neuquén basin in west-central Argentina. The rift architecture in the southern sector of this belt was previously interpreted in terms of the present N-S compressive structural trends, assuming the inversion of pre-existing normal faults with the same orientation. Here, we propose that the NW-SE-trending El Manzano-Liu Cullín lineament, located in the northern termination of the Sierra Azul, reflects the presence of a half-graben master fault in the subsurface. This hypothesis is supported by subsurface data, a balanced cross section, and it is tested using a series of scaled sandbox analogue models. We suggest that the lineament responds to a reactivated NW-trending half-graben fault, hidden by the mainly N-S-trending Andean structures. The proposed orientation is in agreement with the NE-SW extension developed in the Neuquén basin during the Triassic-Early Jurassic. The modeling of the inverted oblique half-graben reveals that the strikes of the main structures of inversion-related belts may often be independent of the orientation of the previously developed extensional system, providing a new perspective for their interpretation.

  11. Paleostress field reconstruction and revised tectonic history of the Donbas fold and thrust belt (Ukraine and Russia)

    Science.gov (United States)

    Saintot, Aline; Stephenson, Randell; Brem, Arjan; Stovba, Sergiy; Privalov, Vitaliy

    2003-10-01

    In the WNW-ESE Donbas fold belt (DF), inversion of 3500 microtectonic data collected at 135 sites, in Proterozoic, Devonian, Carboniferous, and Cretaceous competent rocks allowed reconstruction of 123 local stress states. Accordingly, four successive paleostress fields reveal the tectonic evolution of the DF. At the numerous sites that have been affected by polyphase tectonics, the chronology between local paleostress states (also paleostress fields) was established using classical criteria (crosscutting striae, pre- or post-folding stress states, stratigraphic control). The oldest event is an extensional stress field with NNE-SSW σ3. It corresponds to the rifting phases that generated the basin in Devonian times and its early Visean reactivation. Later, the DF was affected by a transtension, with NW-SE σ3 characterizing Early Permian tectonism, including the development of the "Main Anticline" of the DF and the pronounced uplift of its southern margin and Ukrainian Shield. Two paleostress fields characterize the Cretaceous/Paleocene inversion of the DF, which was accompanied by folding and thrusting. Both are compressional in type but differ by the trend of σ1, which was first NW-SE and subsequently N-S. The discrete paleostress history of the DF allows a revised interpretation of its tectonic evolution with significant implications for understanding the geodynamic evolution of the southern margin of the East European Craton.

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

    Institute of Scientific and Technical Information of China (English)

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

    2010-01-01

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

  13. Taxi driver seat belt wearing in Nanjing, China.

    Science.gov (United States)

    Routley, Virginia; Ozanne-Smith, Joan; Qin, Yu; Wu, Ming

    2009-01-01

    To determine and validate patterns of seat belt use and attitudes of taxi drivers on wearing a seat belt following national and provincial seat belt legislation in 2004-2005. Roadside daylight seat belt observation and interview survey methods were used, as well as observations from inside taxis during routine trips and a taxi driver focus group. The setting was Nanjing, Jiangsu Province, PR China in April of 2006 and 2007. Prevalence of seat belt use and attitudes to wearing a seat belt were determined, as were vehicle and driver characteristics, and comparisons with other motor-vehicle driver's seat belt use and attitudes. Taxi drivers interviewed were predominantly male and aged 30-39 years. They spent more hours per week in their vehicles and had more driving experience than other drivers. Over half (56.2%) of taxi drivers interviewed reported that they always wore seat belts, while observation of taxi drivers showed lower wearing rates (i.e., roadside observation was 43.8%, and observation from inside taxis was 36.2%). Belt tampering was a practice of 12-15% of taxi drivers. "Fine avoidance, safety, high speed and long trips" were given as important reasons for wearing and "feeling trapped and uncomfortable" for not wearing. Seat belt reminder signs in taxis were common (82.6% of taxis), but did not appear to impact on driver seat belt use. The four research methods found taxi drivers to have consistently low "correct wearing" rates. As in several other countries, taxi drivers are particularly resistant to seat belt use. Innovative strategies, including occupational health and safety approaches, may be required to achieve increased levels of seat belt use.

  14. Aortic ruptures in seat belt wearers.

    Science.gov (United States)

    Arajärvi, E; Santavirta, S; Tolonen, J

    1989-09-01

    Several investigations have indicated that rupture of the thoracic aorta is one of the leading causes of immediate death in victims of road traffic accidents. In Finland in 1983, 92% of front-seat passengers were seat belt wearers on highways and 82% in build-up areas. The mechanisms of rupture of the aorta have been intensively investigated, but the relationship between seat belt wearing and injury mechanisms leading to aortic rupture is still largely unknown. This study comprises 4169 fatally injured victims investigated by the Boards of Traffic Accident Investigation of Insurance Companies during the period 1972 to 1985. Chest injuries were recorded as the main cause of death in 1121 (26.9%) victims, 207 (5.0%) of those victims having worn a seat belt. Aortic ruptures were found at autopsy in 98 victims and the exact information of the location of the aortic tears was available in 68. For a control group, we analyzed 72 randomly chosen unbelted victims who had a fatal aortic rupture in similar accidents. The location of the aortic rupture in unbelted victims was more often in the ascending aorta, especially in drivers, whereas in seat belt wearers the distal descending aorta was statistically more often ruptured, especially in right-front passengers (p less than 0.05). The steering wheel predominated statistically as the part of the car estimated to have caused the injury in unbelted victims (37/72), and some interior part of the car was the most common cause of fatal thoracic impacts in seat belt wearers (48/68) (p less than 0.001). The mechanism of rupture of the aorta in the classic site just distal to the subclavian artery seems to be rapid deceleration, although complex body movements are also responsible in side impact collisions. The main mechanism leading to rupture of the ascending aorta seems to be severe blow to the bony thorax. This also often causes associated thoracic injuries, such as heart rupture and sternal fracture. Injuries in the ascending

  15. Deepwater fold and thrust belt classification, tectonics, structure and hydrocarbon prospectivity: A review

    Science.gov (United States)

    Morley, C. K.; King, R.; Hillis, R.; Tingay, M.; Backe, G.

    2011-01-01

    and Type 2 systems is reservoir rock. High quality, continent-derived, quartz-rich sandstones are generally prevalent in Type 1 systems. More diagenetically reactive minerals derived from igneous and ophiolitic sources are commonly present in Type 2 systems, or many are simply poor in well-developed turbidite sandstone units. However, some Type 2 systems, particularly those adjacent to active orogenic belts are partially sourced by high quality continent-derived sandstones (e.g. NW Borneo, S. Caspian Sea, Columbus Basin). In some cases very high rates of deposition in accretionary prisms adjacent to orogenic belts, coupled with uplift due to collision, results in accretionary prism related fold belts that pass laterally from sub-aerial to deepwater conditions (e.g. S. Caspian Sea, Indo-Burma Ranges). The six major hydrocarbon producing regions of DWFTBs worldwide (Gulf of Mexico, Niger Delta, NW Borneo, Brazil, West Africa, S. Caspian Sea) stand out as differing from most other DWFTBs in certain fundamental ways, particularly the very large volume of sediment deposited in the basins, and/or the great thickness and extent of salt or overpressured shale sdetachments.

  16. Modal analysis of coupled vibration of belt drive systems

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-jun; CHEN Li-qun

    2008-01-01

    The modal method is applied to analyze coupled vibration of belt drive systems. A belt drive system is a hybrid system consisting of continuous belts modeled as strings as well as discrete pulleys and a tensioner arm. The characteristic equation of the system is derived from the governing equation. Numerical results demenstrate the effects of the transport speed and the initial tension on natural frequencies.

  17. Soil thermal regime and geomorphogenesis at Fuentes Carrionas massif (Cantabrian Range, NW Iberian Peninsula).

    Science.gov (United States)

    Pellitero, Ramon; Serrano Cañadas, Enrique

    2015-04-01

    Fuentes Carrionas is a massif within the Cantabrian Range, in NW Iberian Peninsula. Its altitude ranges between 1400 and 2500 meters and its climate is an oceanic/Mediterranean transition one, with cold temperatures and heavy snowfall in the winter/early spring season, and a warm and dry summer season. Due to its outstanding altitude and lithological variety in the Cantabrian Range context, Fuentes Carrionas holds some periglacial activity (gelifluction, frost shattering) which is absent elsewhere in NW Iberian Peninsula. This work is relates the soil thermal regime across the mountain gradient to landforms formation. 14 thermometers (11 i-button, protected in a plastic can, and three UTL data loggers) were buried at a shallow depth (10 cm.) between autumn 2009 and summer 2012. 12 thermometers were placed between 1900 and 2400 m.a.s.l. at 250 meters altitude interval at the four main aspects. Two additional thermometers were place in the Curavacas N face for permafrost identification. Thermometers were calibrated to yield a measurement every 6 hours starting from 8 AM during one year's time. Data was collected annually in the summer season. Some additional soil temperature data was obtained from an external project in the same area for the 2007-2009 interval. In this case thermometers were "Hobbo" model, and they were also buried to a shallow depth. Results show a permafrost free mountain range. Annual average soil temperatures range between 1 and 8 degrees Celsius. Snow pack appears as a decisive factor in winter temperatures, as the zero curtain effect can be tracked in many cases. Snow cover patterns show a distinctive behavior between S and N aspects, with a 3 months snow cover on the southern faces and between 6 and 9 at the northern analogues. This cover has a relevant impact on geomorphological processes. There is a clear relation between spring snow melt and solifluction or channelized erosion. Also, snow cover prevents the occurrence of freeze/thaw cycles

  18. Period Determination of Six Main Belt Asteroids

    Science.gov (United States)

    Ferrero, Andrea

    2014-07-01

    Observations of six main-belt asteroids (MBA) produced lightcurve parameters of: 487 Venetia, P = 13.34 ± 0.01 h, A = 0.20 mag; 684 Hildburg, P = 15.89 ± 0.01 h, A = 0.22 mag; 772 Tanete, P = 8.629 ± 0.001 h, A = 0.18 mag.; 1181 Lilith, P = 15.04 ± 0.01 h, A = 0.11 mag.; 1246 Chaka, P = 25.44 ± 0.01 h, A = 0.25 mag.; and 2834 Christy Carol, P = 12.79 ± 0.01 h, A = 0.39 mag.

  19. Water activities in the Kerala Khondalite Belt

    Science.gov (United States)

    Chacko, Thomas; Kumar, G. R. Ravindra; Peterson, J. W.

    1988-01-01

    The author and colleagues presented their determinations of water activities in various granulite-facies rocks of the Kerala Khondalite Belt. Using mineral equilibria, thermodynamic data, and assumed geopressure-geotemperature conditions of 5.5 kbar and 750 C, they calculated uniformly low a(H2O) values of about 0.27 over a large geographic region. They suggested that these conditions were produced by the presence of abundant CO2-rich fluids, derived either from deeper levels or from metamorphic reactions involving graphite.

  20. Linear Motor for Drive of Belt Conveyor

    Directory of Open Access Journals (Sweden)

    Milan Krasl

    2006-01-01

    Full Text Available This paper introduces a novel approach on the design of a linear motor for drive of belt conveyor (LMBC. The motor is a simple combination of asynchronous motor in plane. The electromagnetic forces is one of the most important parameters of electrical machines. This parameter is necessary for the checking of the design. This paper describes several variants: linear motor with slots in platens, slots in one half of platens and optimization of slots. The electromagnetic force can be found with the help of a Finite Elements Method – based program. For solution was used QuickField program.

  1. Solar Neutrons and the Earth's Radiation Belts.

    Science.gov (United States)

    Lingenfelter, R E; Flamm, E J

    1964-04-17

    The intensity and spectrum of solar neutrons in the vicinity of the earth are calculated on the assumption that the low-energy protons recently detected in balloon and satellite flights are products of solar neutron decay. The solar-neutron flux thus obtained exceeds the global average cosmic-ray neutron leakage above 10 Mev, indicating that it may be an important source of both the inner and outer radiation belts. Neutron measurements in the atmosphere are reviewed and several features of the data are found to be consistent with the estimated solar neutron spectrum.

  2. Parametric resonances of convection belt system

    Institute of Scientific and Technical Information of China (English)

    Zhi-an YANG; Gao-feng LI

    2009-01-01

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

  3. Orion revisited. III. The Orion Belt population

    Science.gov (United States)

    Kubiak, K.; Alves, J.; Bouy, H.; Sarro, L. M.; Ascenso, J.; Burkert, A.; Forbrich, J.; Großschedl, J.; Hacar, A.; Hasenberger, B.; Lombardi, M.; Meingast, S.; Köhler, R.; Teixeira, P. S.

    2017-02-01

    Aims: This paper continues our study of the foreground population to the Orion molecular clouds. The goal is to characterize the foreground population north of NGC 1981 and to investigate the star formation history in the large Orion star-forming region. We focus on a region covering about 25 square degrees, centered on the ɛ Orionis supergiant (HD 37128, B0 Ia) and covering the Orion Belt asterism. Methods: We used a combination of optical (SDSS) and near-infrared (2MASS) data, informed by X-ray (XMM-Newton) and mid-infrared (WISE) data, to construct a suite of color-color and color-magnitude diagrams for all available sources. We then applied a new statistical multiband technique to isolate a previously unknown stellar population in this region. Results: We identify a rich and well-defined stellar population in the surveyed region that has about 2000 objects that are mostly M stars. We infer the age for this new population to be at least 5 Myr and likely 10 Myr and estimate a total of about 2500 members, assuming a normal IMF. This new population, which we call the Orion Belt population, is essentially extinction-free, disk-free, and its spatial distribution is roughly centered near ɛ Ori, although substructure is clearly present. Conclusions: The Orion Belt population is likely the low-mass counterpart to the Ori OB Ib subgroup. Although our results do not rule out Blaauw's sequential star formation scenario for Orion, we argue that the recently proposed blue streams scenario provides a better framework on which one can explain the Orion star formation region as a whole. We speculate that the Orion Belt population could represent the evolved counterpart of an Orion nebula-like cluster. The catalog (Full Table A.1) is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/598/A124

  4. CHAOTIC BELT PHENOMENA IN NONLINEAR ELASTIC BEAM

    Institute of Scientific and Technical Information of China (English)

    张年梅; 杨桂通

    2003-01-01

    The chaotic motions of axial compressed nonlinear elastic beam subjected totransverse load were studied. The damping force in the system is nonlinear. Consideringmaterial and geometric nonlinearity, nonlinear governing equation of the system wasderived. By use of nonlinear Galerkin method, differential dynamic system was set up.Melnikov method was used to analyze the characters of the system. The results showed thatchaos may occur in the system when the load parameters P0 and f satisfy some conditions.The zone of chaotic motion was belted. The route from subharmonic bifurcation to chaoswas analyzed. The critical conditions that chaos occurs were determined.

  5. The Radiation Belt Storm Probes Mission: Advancing Our Understanding of the Earth's Radiation Belts

    Science.gov (United States)

    Sibeck, David; Kanekal, Shrikanth; Kessel, Ramona; Fox, Nicola; Mauk, Barry

    2012-01-01

    We describe NASA's Radiation Belt Storm Probe (RBSP) mission, whose primary science objective is to understand, ideally to the point of predictability, the dynamics of relativistic electrons and penetrating ions in the Earth's radiation belts resulting from variable solar activity. The overarching scientific questions addressed include: 1. the physical processes that produce radiation belt enhancement events, 2. the dominant mechanisms for relativistic electron loss, and 3. how the ring current and other geomagnetic processes affect radiation belt behavior. The RBSP mission comprises two spacecraft which will be launched during Fall 2012 into low inclination lapping equatorial orbits. The orbit periods are about 9 hours, with perigee altitudes and apogee radial distances of 600 km and 5.8 RE respectively. During the two-year primary mission, the spacecraft orbits precess once around the Earth and lap each other twice in each local time quadrant. The spacecraft are each equipped with identical comprehensive instrumentation packages to measure, electrons, ions and wave electric and magnetic fields. We provide an overview of the RBSP mission, onboard instrumentation and science prospects and invite scientific collaboration.

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

    Science.gov (United States)

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

    2016-06-01

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

  7. Zircon SHRIMP dating of granite from Qaidamshan,NW China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Zircon SHRIMP dating from Qaidamshan granite shows that the granite age is 446 Ma, similar to that of eclogite in the UHP belt. We think that both granite and eclogite may be formed at different stages during tectonic evolution of this area. Together with other studies we suggested that the collision of ocean and continent plates may occur at the early Caledonian in this area, forming the eclogite, and the collision of continent and continent plates at the late Caledonian, forming the Qaidamshan granite with the zircon SHRIMP age of 446 Ma.

  8. Remagnetization in the Monterrey Salient (NE Mexico) and regional tecto-magnetic events in the Mexican Fold-Thrust Belt

    Science.gov (United States)

    Nemkin, S. R.; Chavez-Cabello, G.; Fitz-Diaz, E.; van der Pluijm, B.; Van Der Voo, R.

    2016-12-01

    In the 1980's, carbonate remagnetizations became widely recognized, with many units re-analyzed to examine these later magnetization events. In this study we focus on the Lower Cretaceous La Peña-Cupido formations transition from the Monterrey Salient in Northeast Mexico, at the external most part of the Mexican Fold-Thrust Belt in this area. The remagnetization observed is carried by single domain (SD) magnetite, resulting from chemical growth of magnetite in a range of superparamagnetic (SPM) to SD grain sizes. In order to determine the relative remagnetization age, local km-scale folds were sampled for paleomagnetic fold tests. The application resulted in 8 syn-folding (1 a regional test) and 4 pre-folding remagnetizations (1 a regional application). Syn-folding results are found in the N-S to NW-SE trending portion of the Monterrey Salient and pre-folding results in the E-W trending segment of the belt. By combining syn-folding results with Ar/Ar illite ages of folds, a remagnetization age of 51 + 4 Ma is obtained in folded limestone samples. Relatively strong ferrimagnetic signals from sites with syn-folding remagnetizations suggest that more magnetite growth occurred in these folds, as compared to pre-folding sites where paramagnetic and diamagnetic signals are more dominant. Based on the relative timing of remagnetization, deformation progressed from the SW to the NE in northern Mexican Fold-Thrust Belt. Prior results (Nemkin et al., 2015) from the central Sierra Madre Oriental, to the south, showed two remagnetization events; 77 Ma and 44 Ma from W to E. Based on the timing of remagnetization in the new study area, folding and remagnetization in the Monterrey Salient occurred in between these events to the south.

  9. THE TECTONOPHYSICAL RESEARCHES OF THE SEMISAMSKAYA ANTICLINE (NORTH-WESTERN CAUCASUS FOLD AND THRUST BELT

    Directory of Open Access Journals (Sweden)

    A. V. Marinin

    2015-09-01

    Full Text Available Structural paragenetic and cataclastic analysis methods were applied to study tectonic fracturing within one of the folds of the southern wing of the North-Western Caucasus fold-and-thrust belt. The object of the study was the Semisamskaya anticline (Fig. 1 and 2 comprising the Upper Cretaceous and Paleogenic layered terrigenic-carbonate sediments that contain various well-developed geological indicators of palaeostresses (Fig. 3, 5, 7, and 9.In the folded structure under study, a paragenesis is revealed which is associated with the effect of sub-horizontal minimum compression (deviator extension stresses of the north-western orientation (NW 320° and traced by detached normal fault systems striking in the north-eastern direction (Fig. 6, 8, 10, 11, and 17. Upthrust-overthrust systems of the north-western strike (NW–SE, which are of importance for the whole folded structure of the North-Western Caucasus, are mainly manifested in the wings of the Semisamskaya anticline (Fig. 6, 12, and 13.The overall field of stresses related to formation of the folded structure is significantly variable as evidenced by the pattern of local parameters of the paleostress field, which are calculated by the cataclastic analysis method (Figure 15, 16, and 17.It is established that the geodynamic regime within the anticline is considerably variable by types (Fig. 18. Areas with horizontal extension in the axial part of the fold are replaced by areas of horizontal compression at its wings (Fig. 19.  

  10. Effects of driver characteristics on seat belt fit.

    Science.gov (United States)

    Reed, Matthew P; Ebert, Sheila M; Hallman, Jason J

    2013-11-01

    A laboratory study of posture and belt fit was conducted with 46 men and 51 women, 61% of whom were age 60 years or older and 32% age 70 years or older. In addition, 28% of the 97 participants were obese, defined as body mass index ≥ 30 kg/m^2. A mockup of a passenger vehicle driver's station was created and five belt anchorage configurations were produced by moving the buckle, outboard-upper (D-ring), and outboard-lower anchorages. An investigator recorded the three-dimensional locations of landmarks on the belt and the participant's body using a coordinate measurement machine. The location of the belt with respect to the underlying skeletal structures was analyzed, along with the length of belt webbing. Using linear regression models, an increase in age from 20 to 80 years resulted in the lap belt positioned 18 mm further forward relative to the pelvis, 26 mm greater lap belt webbing length, and 19 mm greater shoulder belt length. An increase in stature of 350 mm (approximately the range from 5th-percentile female to 95th-percentile male in the U.S. population) was associated with the lap belt 14 mm further forward relative to the pelvis, the shoulder belt 37 mm more outboard relative to the body centerline, and 38 mm less shoulder belt webbing length. Among the driver factors considered, body mass index had the greatest effects. An increase of BMI in 20 kg/m^2, which spans approximately the central 90% of U.S. adults, was associated with the lap belt being placed 102 mm further forward and 94 mm higher, relative to the pelvis, and increases in lap and shoulder belt webbing length of 276 and 258 mm, respectively. Gender did not have important effects on the analyzed belt fit measures after taking into account stature and body mass index. These results offer important considerations for future crash safety assessments and suggest that further research is needed to consider belt fit for older and obese occupants.

  11. Buried Quaternary Valleys In NW Europe - Aquifers and Drilling Hazards

    Science.gov (United States)

    Huuse, M.; Lykke-Andersen, H.; Piotrowski, J.

    Buried Quaternary valleys are extremely widespread in the formerly glaciated, low- land areas of NW Europe (Huuse &Lykke-Andersen 2000, Fig. 4). The valleys may be several hundred metres deep, some kilometres across and few to several tens of kilometres long. Most of the deep valleys have irregular length profiles with sills and basins, unlike standard subaerial river systems. We interpret these as overdeepened valleys, formed mainly by subglacial meltwater erosion. Buried valleys located on- shore often provide sheltered reservoirs of clean groundwater, and much attention is presently focused on locating onshore valleys and quantifying their potential as groundwater aquifers. In nearshore areas, buried valleys may be a risk factor by pro- viding pathways of salt-water intrusion of onshore groundwater aquifers. Far offshore, buried valleys are located in the shallow subsurface above the prolific oil and gas fields of the central North Sea. Here, the valleys pose a risk for drilling operations by hosting shallow gas and potentially unstable sediments. The central North Sea is now largely covered by 3D seismic data, which often image the buried valleys in a level of de- tail much greater than that available onshore. Hence offshore valleys imaged by 3D seismic data may be used as analogues for groundwater reservoirs onshore NW Eu- rope. Here, we present examples of buried valleys from onshore, nearshore and far offshore locations, to illustrate how genetically and morphologically identical valleys may benefit or hamper the exploitation of subsurface accummulations of groundwater and hydrocarbons. Huuse, M. &Lykke-Andersen, H. 2000. Buried Quaternary valleys in the eastern Dan- ish North Sea: morphology and origin. Quaternary Science Reviews 19, 1233-1253.

  12. Fading of Jupiter's South Equatorial Belt

    Science.gov (United States)

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

    2011-01-01

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

  13. Distribution of dust from Kuiper belt objects

    CERN Document Server

    Gorkavyi, N N; Taidakova, T; Mather, J C; Gorkavyi, Nick N.; Ozernoy, Leonid M.; Taidakova, Tanya; Mather, John C.

    2000-01-01

    (Abridged) Using an efficient computational approach, we have reconstructed the structure of the dust cloud in the Solar system between 0.5 and 100 AU produced by the Kuiper belt objects. Our simulations offer a 3-D physical model of the `kuiperoidal' dust cloud based on the distribution of 280 dust particle trajectories produced by 100 known Kuiper belt objects ; the resulting 3-D grid consists of $1.9\\times 10^6$ cells containing $1.2\\times 10^{11}$ particle positions. The following processes that influence the dust particle dynamics are taken into account: 1) gravitational scattering on the eight planets (neglecting Pluto); 2) planetary resonances; 3) radiation pressure; and 4) the Poynting-Robertson (P-R) and solar wind drags. We find the dust distribution highly non-uniform: there is a minimum in the kuiperoidal dust between Mars and Jupiter, after which both the column and number densities of kuiperoidal dust sharply increase with heliocentric distance between 5 and 10 AU, and then form a plateau betwee...

  14. Chaotic Diffusion of Resonant Kuiper Belt Objects

    CERN Document Server

    Tiscareno, Matthew S

    2008-01-01

    We carried out extensive numerical orbit integrations to probe the long-term chaotic dynamics of the two strongest mean motion resonances of Neptune in the Kuiper belt, the 3:2 (Plutinos) and 2:1 (Twotinos). Our primary results include a computation of the relative volumes of phase space characterized by large- and small-resonance libration amplitudes, and maps of resonance stability measured by mean chaotic diffusion rate. We find that Neptune's 2:1 resonance has weaker overall long-term stability than the 3:2 -- only 15% of Twotinos are projected to survive for 4 Gyr, compared to 28% of Plutinos. We find that Pluto has only a modest effect, causing a ~4% decrease in the Plutino population that survives to 4 Gyr. Given current observational estimates, we conclude that the primordial populations of Plutinos and Twotinos formerly made up more than half the population of the classical and resonant Kuiper Belt. We also conclude that Twotinos were originally nearly as numerous as Plutinos, consistent with models ...

  15. The Dynamical Evolution of the Asteroid Belt

    CERN Document Server

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

    2015-01-01

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

  16. Young Stellar Objects in the Gould Belt

    CERN Document Server

    Dunham, Michael M; Evans, Neal J; Broekhoven-Fiene, Hannah; Cieza, Lucas; Di Francesco, James; Gutermuth, Robert A; Harvey, Paul M; Hatchell, Jennifer; Heiderman, Amanda; Huard, Tracy; Johnstone, Doug; Kirk, Jason M; Matthews, Brenda C; Miller, Jennifer F; Peterson, Dawn E; Young, Kaisa E

    2015-01-01

    We present the full catalog of Young Stellar Objects (YSOs) identified in the 18 molecular clouds surveyed by the Spitzer Space Telescope "cores to disks" (c2d) and "Gould Belt" (GB) Legacy surveys. Using standard techniques developed by the c2d project, we identify 3239 candidate YSOs in the 18 clouds, 2966 of which survive visual inspection and form our final catalog of YSOs in the Gould Belt. We compile extinction corrected SEDs for all 2966 YSOs and calculate and tabulate the infrared spectral index, bolometric luminosity, and bolometric temperature for each object. We find that 326 (11%), 210 (7%), 1248 (42%), and 1182 (40%) are classified as Class 0+I, Flat-spectrum, Class II, and Class III, respectively, and show that the Class III sample suffers from an overall contamination rate by background AGB stars between 25% and 90%. Adopting standard assumptions, we derive durations of 0.40-0.78 Myr for Class 0+I YSOs and 0.26-0.50 Myr for Flat-spectrum YSOs, where the ranges encompass uncertainties in the ado...

  17. Seat belt utilisation and awareness in UAE.

    Science.gov (United States)

    Bendak, S; Al-Saleh, K

    2013-01-01

    Seat belts (SBs) are effective devices for reducing injury risk due to traffic accidents. Seat belt wearing was made compulsory in the United Arab Emirates (UAE) in January 1999 for drivers and front seat passengers (FSPs). No comprehensive study has ever assessed SB wearing rates across the country. Also, little is known on drivers' awareness of the importance of wearing seatbelts and how human factors affect wearing habits. This study aims to determine SB wearing rates for drivers and FSPs in UAE through an observational field study. It also aims to investigate perceptions and behaviour of drivers on this issue as well as human factors that affect wearing rate through a randomly distributed questionnaire. The results of the field study show that the overall SB wearing rate across the country was 61% for drivers and 43.4% for FSPs and that there were significant differences between the seven emirates that constitute the country. The questionnaire results show that age, education level, gender, marital status and nationality of drivers affect wearing habits and perceptions. Future implications in terms of improving traffic safety awareness are discussed.

  18. Geology Spatial Data Mining Method for Regional Metallogenic Prediction%基于地质空间数据挖掘的区域成矿预测方法

    Institute of Scientific and Technical Information of China (English)

    何彬彬; 崔莹; 陈翠华; 陈建华

    2011-01-01

    以多源地质空间数据库和空间数据挖掘技术为基础,顾及地质数据的空间特征和不确定性,提出一种基于地质空间数据挖掘的区域成矿预测方法,主要包括:连续型地质空间数据离散化、成矿空间关系提取及属性化、成矿关联规则提取及质量评价、成矿关联规则综合评价与潜力制图.最后,以青海省东昆仑地区铁矿资源潜力预测为例进行实验,并将地质空间数据挖掘预测结果与传统的证据权模型预测结果进行对比.实验对比结果表明,基于地质空间数据挖掘的预测结果较传统的证据权模型方法预测精度更高,该方法用于区域成矿预测效果良好.%Spatial data mining (SDM) refers to extracting and "mining" the hidden, implicit, valid, novel and interesting spatial or non-spatial patterns or rules from a large amount of, incomplete, noisy, fuzzy, random, and practical spatial databases. At present, SDM mainly concentrates on the efficiency of mining algorithm itself. Another important issue-application in SDM-has not been paid much attention to. Geological data are typical spatial data, which include geological, geophysical, geochemical, and remote sensing data. Regional metallogenic prediction and quantitative resource assessment have been recognized as important when integrating multi-source geological spatial data in recent years. The statistical and mathematical approaches that have developed recently for multiresources geological spatial data integration include weights-of -evidence modelling, and the logistic regression modeling. The fuzzy logic model, artificial neural networks model and the fractal method have been applied in the prediction and assessment of mineral resources potential. These methods promote the effectiveness of mineral resource prospecting. However, under the shortage of mineral resources and the leap cost of prospecting and exploring, how to make full use of the existing multi-sources geo

  19. 评流行的岩浆热液成矿理论%Granite and metallogenic relationship discussion (1):COMMENT ON THE POPULAR MAGMATIC HYDROTHERMAL MINERALIZATION THEORY

    Institute of Scientific and Technical Information of China (English)

    张旗

    2012-01-01

    The popular magmatic hydrothermal metallogenic theory assumed that hydrothermal and ore-bearing metal are produced from the magma by differentiation and evolution.In the late magmatic differentiation,hydrothermal can be soluble after reaching oversaturation and hydrothermal mineralization are taken place in the deuteric stage or postmagmatic stage.The magma and hydrothermal deposits are closely related in space,time and genesis.The author thinks that the theory has many problems.First of all,the lower crust is lack of water,the water content of the lower crust is probably not more than 1%,therefore,the partial melting of the granitic magma is probably produced under the condition of lack water rather than rich water,and the granite is rarely rich water.Secondly,the granitic magma cannot differentiated and evolved because of the high viscosity.Thirdly,when magma consolidation the temperature and pressure decrease,most of the water in the form of(OH) into rock-forming minerals,almost no much free water is isolated,also no such evidence found in field.The ore hydrothermal mainly comes from the lower crust.As long as there is enough heat,lower crust metamorphic rocks with the structure water mineral can happen dehydration melting.The temperature of dehydration melting is lower than that of partial melting of granitic magma,so the dehydration melting can happen earlier and the melting range is bigger.Hydrothermal in the form of free water is produced and circulated in the lower crust,and it also can enrich ore-bearing metal elements.Granitic magma can also include hydrothermal and ore-bearing metal elements when partial melting happens,as to whether it is the main source of all kinds of magmatic hydrothermal deposit metal elements is the matter that needs to discuss.What the lower crust inside happened is very different.Therefore,the popular magmatic hydrothermal metallogenic theory is just a conjecture,cannot be a mature theory.But,do not eliminate the special

  20. Modulation of forelimb and hindlimb muscle activity during quadrupedal tied-belt and split-belt locomotion in intact cats.

    Science.gov (United States)

    Frigon, A; Thibaudier, Y; Hurteau, M-F

    2015-04-02

    The modulation of the neural output to forelimb and hindlimb muscles when the left and right sides step at different speeds from one another in quadrupeds was assessed by obtaining electromyography (EMG) in seven intact adult cats during split-belt locomotion. To determine if changes in EMG during split-belt locomotion were modulated according to the speed of the belt the limb was stepping on, values were compared to those obtained during tied-belt locomotion (equal left-right speeds) at matched speeds. Cats were chronically implanted for EMG, which was obtained from six muscles: biceps brachii, triceps brachii, flexor carpi ulnaris, sartorius, vastus lateralis and medial gastrocnemius. During tied-belt locomotion, cats stepped from 0.4 to 1.0m/s in 0.1m/s increments whereas during split-belt locomotion, cats stepped with left-right speed differences of 0.1 to 0.4m/s in 0.1m/s increments. During tied-belt locomotion, EMG burst durations and mean EMG amplitudes of all muscles respectively decreased and increased with increasing speed. During split-belt locomotion, there was a clear differential modulation of the EMG patterns between flexors and extensors and between the slow and fast sides. Changes in the EMG pattern of some muscles could be explained by the speed of the belt the limb was stepping on, while in other muscles there were clear dissociations from tied-belt values at matched speeds. Therefore, results show that EMG patterns during split-belt locomotion are modulated to meet task requirements partly via signals related to the stepping speed of the homonymous limb and from the other limbs.

  1. Ambient Response Analysis of the Great Belt Bridge

    DEFF Research Database (Denmark)

    Brincker, Rune; Frandsen, J. B.; Andersen, P.

    2000-01-01

    In this paper an ambient response analysis of the Great Belt Bridge is presented. The Great Belt Bridge is one of the largest suspension bridges in the world, and the analysis was carried out in order to investigate the possibilities of estimating reliable damping values from the ambient response...

  2. Increasing of horizontal velocity of particles leaving a belt conveyor

    Directory of Open Access Journals (Sweden)

    Tavares Abraão

    2017-01-01

    Full Text Available We investigate the transport of granular materials by a conveyor belt via numerical simulations. We report an unusual increasing of particles horizontal velocity when they leave the belt and initiate free-fall. Using Discrete Elements Method, the mechanism underlying this phenomenon were investigated, and a study on how particle and system properties influences this effect were conducted.

  3. Teaching Taekwondo in Physical Education: Incorporating the Color Belt System

    Science.gov (United States)

    Oh, Hyun-Ju; Hannon, James C.; Banks, Aaron

    2006-01-01

    Taekwondo is an excellent lifetime physical activity that provides both physical and mental benefits to its participants. The color belt system may be creatively used in physical education to encourage improvement in all learning domains. This article provides information on incorporating the color belt system into physical education, and provides…

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

    Science.gov (United States)

    Bhaskar, Anand; Subramani, Selvam; Ojha, Rajdeep

    2013-01-01

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

  5. Teaching Taekwondo in Physical Education: Incorporating the Color Belt System

    Science.gov (United States)

    Oh, Hyun-Ju; Hannon, James C.; Banks, Aaron

    2006-01-01

    Taekwondo is an excellent lifetime physical activity that provides both physical and mental benefits to its participants. The color belt system may be creatively used in physical education to encourage improvement in all learning domains. This article provides information on incorporating the color belt system into physical education, and provides…

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

    Science.gov (United States)

    Bhaskar, Anand; Subramani, Selvam; Ojha, Rajdeep

    2013-01-01

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

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

    NARCIS (Netherlands)

    Valtonen, J.

    1992-01-01

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

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

    NARCIS (Netherlands)

    Grant, B.A.

    1992-01-01

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

  9. HUMAN NEURONAL INTERLIMB COORDINATION DURING SPLIT-BELT LOCOMOTION

    NARCIS (Netherlands)

    DIETZ, [No Value; ZIJLSTRA, W; DUYSENS, J

    1994-01-01

    Human interlimb coordination and the adaptations in leg muscle activity were studied during walking on a treadmill with split belts. Four different belt speeds (0.5, 1.0, 1.5, 2.0 m/s) were offered in all possible combinations for the left and right leg. Subjects adapted automatically to a differenc

  10. Human neuronal interlimb coordination during split-belt locomotion

    NARCIS (Netherlands)

    Dietz, V.; Zijlstra, W.G.; Duysens, J.E.J.

    1994-01-01

    Human interlimb coordination and the adaptations in leg muscle activity were studied during walking on a treadmill with split belts. Four different belt speeds (0.5, 1.0, 1.5, 2.0 m/s) were offered in all possible combinations for the left and right leg. Subjects adapted automatically to a differenc

  11. Biomechanical considerations for abdominal loading by seat belt pretensioners.

    Science.gov (United States)

    Rouhana, Stephen W; El-Jawahri, Raed E; Laituri, Tony R

    2010-11-01

    While seat belts are the most effective safety technology in vehicles today, there are continual efforts in the industry to improve their ability to reduce the risk of injury. In this paper, seat belt pretensioners and current trends towards more powerful systems were reviewed and analyzed. These more powerful systems may be, among other things, systems that develop higher belt forces, systems that remove slack from belt webbing at higher retraction speeds, or both. The analysis started with validation of the Ford Human Body Finite Element Model for use in evaluation of abdominal belt loading by pretensioners. The model was then used to show that those studies, done with lap-only belts, can be used to establish injury metrics for tests done with lap-shoulder belts. Then, previously-performed PMHS studies were used to develop AIS 2+ and AIS 3+ injury risk curves for abdominal interaction with seat belts via logistic regression and reliability analysis with interval censoring. Finally, some considerations were developed for a possible laboratory test to evaluate higher-powered pretensioners.

  12. Policy Implications from an Evaluation of Seat Belt Use Regulation.

    Science.gov (United States)

    Desai, Anand; You, Min-Bong

    1992-01-01

    Effects of Ohio's mandatory seat belt law on seat belt use, number of car accidents, and number of fatal and severe injuries were evaluated for January 1982 through March 1988. The monthly average number of accident victims was 2,002. Implications for public policy formulation and implementation are discussed. (SLD)

  13. An Evaluation of the Seat Belt Education Campaign.

    Science.gov (United States)

    Rochon, James

    A seat belt education campaign conducted in Canada to dispel myths surrounding seat belts and promote a better understanding of their functions was evaluated. Two telephone surveys, each comprised of 4,000 respondents, were conducted. The first was done immediately before the campaign and the second immediately succeeding the campaign. Also, a…

  14. Compliance with Seat Belt Use in Makurdi, Nigeria: An ...

    African Journals Online (AJOL)

    2011-03-23

    Mar 23, 2011 ... has been estimated that using seat belts can reduce the risk ... 24‑h direct observational study of seat belt usage among vehicle occupants in Makurdi, Benue. State ... In Nigeria, the Federal Road Safety Corps (FRSC) was.

  15. Wrench tectonics control on Neogene-Quaternary sedimentation along the Mid-Hungarian Mobile Belt

    Science.gov (United States)

    Pogacsas, Gyorgy; Juhász, Györgyi; Mádl-Szőnyi, Judit; Simon, Szilvia; Lukács, Szilveszter; Csizmeg, János

    2010-05-01

    terrain, lying originally between the Central Alpine and Southern Alpine units, reached its recent position by some hundred kilometers strike slip movement, resulting in shifting of depocenters from the SW toward NE. The TISZA unit was characterised by clockwise motion, while counterclockwise rotation of the ALPACA is inferred in Late Oligocene-Miocene. Lower Miocene layers were deposited in depocenters whose subsidence was initiated by escape tectonics, NE-ward displacement of the ALCAPA terrane, and uplifting of the NW-SE oriented Neo-Vardar zone. The Neo-Vardar zone was represented by wide area of continental and alluvial depositional systems. 2. During the middle-late Badenian (15.5-13.6Ma), the ALCAPA collided with the European platform, and the eastward movement of the Tisza-Dacia became pronounced. Because of that the former right lateral motion along the Mid-Hungarian Mobile Belt ceased and a long period of left lateral strike slipe began. Earlier development of pull-apart basins, related to the extensive strike-slip faulting inside the ALCAPA, changed to the graben opening driven by the westward subduction and the eastward motion of the Tisza-Dacia. The middle-late Badenian period was characterised by sediments deposited in listric fault bounded half grabens, in crestal collapse grabens related to (flat-ramp) listric faults, in wide and/or narrow rift systems. Migration of volcanic activity and facies belts took place during relatively short period of times. Large displacements along listric faults have resulted in tilting of originally horizontal strata, and the formation of a regional unconformity between the middle Miocene and the upper Miocene sediments. Wrench fault related pull apart basins were filled by terrestrial to marine sediments. 3. During the Sarmatian-Pannonian (13.6-6.2 Ma), while the eastward motion of the ALPACA was strictly restricted, the Tisza-Dacia unit was able still to move eastward until the last parts of the remnant Carpathian Flysch

  16. Experimental Measurements of Belt Gears in Newly Developed Device

    Directory of Open Access Journals (Sweden)

    Jozef Mascenik

    2016-05-01

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

  17. Nonoperative management of pediatric aortic injury with seat belt syndrome.

    Science.gov (United States)

    Parrish, Dan W; Barnhorst, Amanda; Trebska-McGowan, Katarzyna; Amendola, Michael; Haynes, Jeffrey H

    2015-08-01

    "Seat belt syndrome" was first described by Garret and Braunstein in 1962. The syndrome involves skin and abdominal wall ecchymosis (seat belt sign) intra-abdominal solid organ and visceral injuries, as well as Chance fractures (compression and/or wedging deformity of the anterior portion of the vertebral body with disruption or fracture of the posterior elements, generally at L1-L3). We present a case of a 12-year-old male involved in a high-speed motor vehicle collision wearing only a lap belt resulting in seat belt syndrome, with disruption of the abdominal wall, mesenteric avulsion with multiple intestinal perforations, abdominal aortic dissection, and an L2 Chance fracture with cord transection. Intraoperative decision making is outlined with this scenario of complex injuries, and the literature of seat belt syndrome associated with blunt aortic injuries and its management is reviewed.

  18. Survey of current situation in radiation belt modeling

    Science.gov (United States)

    Fung, Shing F.

    2004-01-01

    The study of Earth's radiation belts is one of the oldest subjects in space physics. Despite the tremendous progress made in the last four decades, we still lack a complete understanding of the radiation belts in terms of their configurations, dynamics, and detailed physical accounts of their sources and sinks. The static nature of early empirical trapped radiation models, for examples, the NASA AP-8 and AE-8 models, renders those models inappropriate for predicting short-term radiation belt behaviors associated with geomagnetic storms and substorms. Due to incomplete data coverage, these models are also inaccurate at low altitudes (e.g., radiation data from modern space missions and advancement in physical modeling and data management techniques have now allowed the development of new empirical and physical radiation belt models. In this paper, we will review the status of modern radiation belt modeling. Published by Elsevier Ltd on behalf of COSPAR.

  19. Landscape distribution characteristics of northern foothill belts of Tianshan Mountains

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The foothill belts of Tianshan Mountains are about 280 km long and 60 km wide, and the study area extends from Kuitun city to Fukang city. They are transitional belts between mountains and plains, appearing in three rows of folds with different morphologies and their age becoming younger from south to north. Based on GIS and RS methods, and materials of the previous researchers, this paper deals with the genetics of the foothill belts and their landscape features resulting from folding by neotectonic movements, and also describes their length, width and slope by remote sensing image interpretation. The characteristics of the foothill belts are found to be very important for the surrounding environment by preventing groundwater from flowing into plains, changing groundwater, increasing flow of surface runoff, in addition to their roles in protecting the surrounding environment. The purpose of this paper is to provide an in-depth understanding of the foothill belts and influence on its surrounding environment.

  20. Detecting extrasolar asteroid belts through their microlensing signatures

    Science.gov (United States)

    Lake, Ethan; Zheng, Zheng; Dong, Subo

    2017-02-01

    We propose that extrasolar asteroid belts can be detected through their gravitational microlensing signatures. Asteroid belt + star lens systems create so-called 'pseudo-caustics', regions in the source plane where the magnification exhibits a finite but discontinuous jump. These features allow such systems to generate distinctive signatures in the microlensing light curves for a wide range of belt configurations, with source trajectories as far as tenths of the Einstein ring radius from the centre of the lens. Sample light curves for a range of asteroid belt parameters are presented. In the near future, space-based microlensing surveys like WFIRST, which will have the power of detecting per cent-level changes in microlensing light curves even with subminute exposure times, may be able to discover extrasolar asteroid belts with masses of the order of an earth mass.

  1. Heads for shifting new generation of belt conveyors

    Energy Technology Data Exchange (ETDEWEB)

    Dembinski, M.

    1980-03-01

    New design of belt conveyors characterized by rigid section joints and conveyor to pontoon joints significantly influences loading of machines shifting belt conveyors to new locations. A new belt conveyor shifting machine head design, called SGP12 (selflocking head for vertical loads up to 120 kN) is described. Design is shown in 4 diagrams. It is stressed that in the SGP-12 the force clamping rollers on rails is automatically controlled depending on the height to which the rails are lifted. Clamping force is proportional to the height. This means of controlling the clamping force excludes damage to the head and reduces wear of the rollers. The SGP12 is, therefore, superior to the GP-12 shifting head of similar capacity. It is suggested that the SGP-12 is characterized by simple design, easier operation, higher reliability and greater safety. The SGP-12 can be used to shift belt conveyors with belts 2250 mm to 3000 mm wide.

  2. Radiation-belt dynamics during solar minimum. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Gussenhoven, M.S.; Mullen, E.G.; Holeman, E.

    1989-12-01

    Two types of temporal variation in the radiation belts are studied using low altitude data taken onboard the DMSP F7 satellite: those associated with the solar cycle and those associated with large magnetic storm effects. Over a three-year period from 1984 to 1987 and encompassing solar minimum, the protons in the heart of the inner belt increased at a rate of approximately 6% per year. Over the same period, outer zone electron enhancements declined both in number and peak intensity. During the large magnetic storm of February 1986, following the period of peak ring current intensity, a second proton belt with energies up to 50 MeV was found at magnetic latitudes between 45 deg. and 55 deg. The belt lasted for more than 100 days. The slot region between the inner and outer electron belts collapsed by the merging of the two populations and did not reform for 40 days.

  3. Long-term subsidence, cooling, and exhumation history along the South Atlantic passive continental margin in NW-Namibia

    Science.gov (United States)

    Menges, Daniel; Glasmacher, Ulrich Anton; Salomon, Eric; Hackspacher, Peter Christian; Schneider, Gabi

    2016-04-01

    has been estimated to ~ 2.7 km in the northeastern and ~ 4 km in the western Kaoko Belt. References 1. Miller, R.McG. Becker, T., 2008. The Geology of Namibia: Ministry of Mines and Energy, Geological Survey (Namibia). 2. Stollhofen, H., 1999. Karoo Synrift-Sedimentation und ihre tektonische Kontrolle am entstehenden Kontinentalrand Namibias: Z.dt.geol.Ges. 149: 519-632. 3. Renne, P.R., Glen, J.M., Milner, S.C., Duncan, A.R., 1996. Age of Etendeka flood volcanism and associated intrusions in southwestern Africa: Geology 24 (7): 659- 662. 4. Salomon, E., Koehn, D., Passchier, C., 2014. Brittle reactivation of ductile shear zones in NW Namibia in relation to South Atlantic rifting: Tectonics 34, 70-85.

  4. Long-term subsidence, cooling, and exhumation history along the South Atlantic passive continental margin in NW-Namibia

    Science.gov (United States)

    Menges, Daniel; Glasmacher, Ulrich Anton; Salomon, Eric; Hackspacher, Peter Christian; Schneider, Gabi

    2017-04-01

    amount of denudation in the last 130 Ma has been estimated to 1.7 km in the northeastern and 3.3 km in the southwestern Kaoko Belt. References 1. Miller, R.McG. Becker, T., 2008. The Geology of Namibia: Ministry of Mines and Energy, Geological Survey (Namibia). 2. Stollhofen, H., 1999. Karoo Synrift-Sedimentation und ihre tektonische Kontrolle am entstehenden Kontinentalrand Namibias: Z.dt.geol.Ges. 149: 519-632. 3. Renne, P.R., Glen, J.M., Milner, S.C., Duncan, A.R., 1996. Age of Etendeka flood volcanism and associated intrusions in southwestern Africa: Geology 24 (7): 659- 662. 4. Salomon, E., Koehn, D., Passchier, C., 2014. Brittle reactivation of ductile shear zones in NW Namibia in relation to South Atlantic rifting: Tectonics 34, 70-85.

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

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Kerstin Saalmann

    2007-01-01

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

  7. Equilibria and Free Vibration of a Two-Pulley Belt-Driven System with Belt Bending Stiffness

    Directory of Open Access Journals (Sweden)

    Jieyu Ding

    2014-01-01

    Full Text Available Nonlinear equilibrium curvatures and free vibration characteristics of a two-pulley belt-driven system with belt bending stiffness and a one-way clutch are investigated. With nonlinear dynamical tension, the transverse vibrations of the translating belt spans and the rotation motions of the pulleys and the accessory shaft are coupled. Therefore, nonlinear piecewise discrete-continuous governing equations are established. Considering the bending stiffness of the translating belt spans, the belt spans are modeled as axially moving beams. The pattern of equilibria is a nontrivial solution. Furthermore, the nontrivial equilibriums of the dynamical system are numerically determined by using two different approaches. The governing equations of the vibration near the equilibrium solutions are derived by introducing a coordinate transform. The natural frequencies of the dynamical systems are studied by using the Galerkin method with various truncations and the differential and integral quadrature methods. Moreover, the convergence of the Galerkin truncation is investigated. Numerical results reveal that the study needs 16 terms after truncation in order to determine the free vibration characteristics of the pulley-belt system with the belt bending stiffness. Furthermore, the first five natural frequencies are very sensitive to the bending stiffness of the translating belt.

  8. Main-belt comets: sublimation-driven activity in the asteroid belt

    CERN Document Server

    Hsieh, Henry H

    2015-01-01

    Our knowledge of main-belt comets (MBCs), which exhibit comet-like activity likely due to the sublimation of volatile ices, yet orbit in the main asteroid belt, has increased greatly since the discovery of the first known MBC, 133P/Elst-Pizarro, in 1996, and their recognition as a new class of solar system objects after the discovery of two more MBCs in 2005. I review work that has been done over the last 10 years to improve our understanding of these enigmatic objects, including the development of systematic discovery methods and diagnostics for distinguishing MBCs from disrupted asteroids (which exhibit comet-like activity due to physical disruptions such as impacts or rotational destabilization). I also discuss efforts to understand the dynamical and thermal properties of these objects.

  9. The JCMT Gould Belt Survey: Understanding the influence of molecular outflows on Gould Belt clouds

    CERN Document Server

    Drabek-Maunder, E; Buckle, J V; Di Francesco, J; Richer, J

    2015-01-01

    Using JCMT Gould Belt Survey data from CO J=3-2 isotopologues, we present a meta-analysis of the outflows and energetics of star-forming regions in several Gould Belt clouds. The majority of the regions are strongly gravitationally bound. There is evidence that molecular outflows transport large quantities of momentum and energy. Outflow energies are at least 20 per cent of the total turbulent kinetic energies in all of the regions studied and greater than the turbulent energy in half of the regions. However, we find no evidence that outflows increase levels of turbulence, and there is no correlation between the outflow and turbulent energies. Even though outflows in some regions contribute significantly to maintaining turbulence levels against dissipation, this relies on outflows efficiently coupling to bulk motions. Other mechanisms (e.g. supernovae) must be the main drivers of turbulence in most if not all of these regions.

  10. Ambient tremors in a collisional orogenic belt

    Science.gov (United States)

    Chuang, Lindsay Yuling; Chen, Kate Huihsuan; Wech, Aaron G.; Byrne, Timothy; Peng, Wei

    2014-01-01

    Deep-seated tectonic tremors have been regarded as an observation tied to interconnected fluids at depth, which have been well documented in worldwide subduction zones and transform faults but not in a collisional mountain belt. In this study we explore the general features of collisional tremors in Taiwan and discuss the possible generation mechanism. In the 4 year data, we find 231 ambient tremor episodes with durations ranging from 5 to 30 min. In addition to a coseismic slip-induced stress change from nearby major earthquake, increased tremor rate is also highly correlated with the active, normal faulting earthquake swarms at the shallower depth. Both the tremor and earthquake swarm activities are confined in a small, area where the high attenuation, high thermal anomaly, the boundary between high and low resistivity, and localized veins on the surfaces distributed, suggesting the involvement of fluids from metamorphic dehydration within the orogen.

  11. NASA's Radiation Belt Storm Probe Mission

    Science.gov (United States)

    Sibeck, David G.

    2011-01-01

    NASA's Radiation Belt Storm Probe (RBSP) mission, comprising two identically-instrumented spacecraft, is scheduled for launch in May 2012. In addition to identifying and quantifying the processes responsible for energizing, transporting, and removing energetic particles from the Earth's Van Allen radiation, the mission will determine the characteristics of the ring current and its effect upon the magnetosphere as a whole. The distances separating the two RBSP spacecraft will vary as they move along their 1000 km altitude x 5.8 RE geocentric orbits in order to enable the spacecraft to separate spatial from temporal effects, measure gradients that help identify particle sources, and determine the spatial extent of a wide array of phenomena. This talk explores the scientific objectives of the mission and the manner by which the mission has been tailored to achieve them.

  12. East Central Uplift Belt of Junggar Basin

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ Mosuowandong ( Z3 ) and Dongdaohaizi (Z4) are two bidding blocks located in the east part of central uplift Belt, the hinterland of Junggar Basin. Xinjiang Uygur Autonomous Region. It totally covers an area of 8 100km2. Topographically, the two blocks are quite gentle with elevation of 380-400 m on average. The north part is desert and the south area is good for farming. There are three ephemeral streams flowing across the desert from south to north. The ground water is buried at the depth ranging from 6 to 8 m. It belongs to continental climate with the annually averaged precipitation of 80 mm. The traffic is rather convenient in the south part of both blocks. There are several sand-paved roads and two asphalt roads connected with the highway from Karamay to Urumqi City.

  13. Subsurface Meridional Circulation in the Active Belts

    CERN Document Server

    Hernandez, I Gonzalez; Hill, F; Howe, R; Komm, R

    2008-01-01

    Temporal variations of the subsurface meridional flow with the solar cycle have been reported by several authors. The measurements are typically averaged over periods of time during which surface magnetic activity existed in the regions were the velocities are calculated. The present work examines the possible contamination of these measurements due to the extra velocity fields associated with active regions plus the uncertainties in the data obtained where strong magnetic fields are present. We perform a systematic analysis of more than five years of GONG data and compare meridional flows obtained by ring-diagram analysis before and after removing the areas of strong magnetic field. The overall trend of increased amplitude of the meridional flow towards solar minimum remains after removal of large areas associated with surface activity. We also find residual circulation toward the active belts that persist even after the removal of the surface magnetic activity, suggesting the existence of a global pattern o...

  14. Petrogenesis and tectonic implications of Permian post-collisional granitoids in the Chinese southwestern Tianshan, NW China

    Science.gov (United States)

    Xia, Bin; Zhang, Lifei; Zhang, Lu

    2016-11-01

    Permian porphyritic granite and leucogranite from the Kekesu and Muzhaerte Valleys in the southwestern (SW) Tianshan orogenic belt, NW China have been studied to decipher their petrogenesis and tectonic implications. For porphyritic granite in the Kekesu Valley, in situ LA-ICPMS zircon U-Pb dating yields crystallization ages of 295-291 Ma. The granite is a high potassic calc-alkaline, slightly peraluminous type, enriched in large ion lithosphere elements (LILE) and light rare earth elements (LREE), but depleted in high field strength elements (HFSE). Zircon Hf isotopic analysis (zircon εHf(t) of -5.8 to -0.2, two-stage Hf model ages of 1323-1680 Ma) and Ti-in-zircon thermometry, which yields crystallization temperatures of 744-749 °C, indicate the parent magma was likely formed by partial melting of a Mesoproterozoic crustal source. By contrast, leucogranite in the Kekesu valley yields crystallization ages of 274-267 Ma. It contains muscovite and garnet, has high silicon and potassium, and is strongly peraluminous. Multiple inherited zircon cores and low zircon crystallization temperatures (687-701 °C), combined with negative zircon εHf(t) values (-7.0 to -4.0), indicate its parent magma was sourced from supracrustal metasedimentary rocks by muscovite-breakdown partial melting. In the Muzhaerte Valley, porphyritic granite has similar major and trace elements characteristics to the Kekesu porphyritic granite. However, its higher zircon εHf(t) values (-0.9 to +3.8) and corresponding lower two-stage Hf model ages (1070-1367 Ma) indicate that the parent magma likely included an input from a more juvenile mantle source. Ti-in-zircon thermometry gives lower crystallization temperature of ∼705 °C. The intrusive relationships between the Permian granitoids and Paleozoic arc plutons, and the LP-HT and (U)HP metamorphic belts, combined with geochronological studies, suggest that these Permian granitoids were generated in a post-collisional environment. It is

  15. Late Neogene exhumation of the Piceance basin, N.W. Colorado, USA: Integrated analysis of multiple thermochronometers and subsidence modeling

    Science.gov (United States)

    Vernon, A. J.; Kendall, J. J.; Becker, T. P.; Patterson, P. E.; Reiners, P. W.; Kapp, J.

    2010-12-01

    The retrograde history of sedimentary basins is often poorly constrained by the study of subsidence, compaction, and thermal diffusion models. As part of industry/academic collaborative research on the fundamental processes active in convergent tectonics we combined multiple paleothermometers, paleobarometers, and thermochronometers on deep borehole samples with modern heat flow measurements to provide powerful constraint for estimating the exhumation history in an area. The Piceance basin (N.W. Colorado) lies east of the leading edge of the Cretaceous to early Eocene Sevier thrust belt, and is flanked by several basement-involved structures (Douglas Creek arch, White River dome, Uinta uplift, White River uplift) that exhibit growth from the Maastrichtian through the late Eocene. The youngest preserved strata within the Piceance basin are within the early Oligocene Uinta Formation, although there are deposits as young as Miocene locally preserved in the region that may have also capped the basin. The timing of uplift, river incision, and plateau-scale exhumation within this region fits into the larger context of the evolution of the Colorado River drainage system. A series of core, cutting, and surface samples were compiled to develop a synthetic well (or vertical section) of over 5000 m. Samples were collected from stratigraphic intervals ranging from the Jurassic to the Eocene and analyzed for apatite and zircon U-Th/He ages, as well as apatite fission track length distributions and ages. As the exhumation model was the unconstrained parameter, the timing and magnitude of the cooling associated with such an event was systematically varied. Thermal histories of each sampled interval were extracted from differing exhumation scenarios in the Piceance basin model (which tracks the temperature and pressure evolution during burial and denudation) and forward modeled using HeFTy. The combined use of several thermochronometers (apatite and zircon U-Th/He, apatite fission

  16. U-Pb Zircon geochronology of the Cambro-Ordovician metagranites and metavolcanic rocks of central and NW Iberia

    Science.gov (United States)

    Talavera, C.; Montero, P.; Bea, F.; González Lodeiro, F.; Whitehouse, M.

    2013-01-01

    New U-Pb zircon data from metagranites and metavolcanic rocks of the Schist-Graywacke Complex Domain and the Schistose Domain of Galicia Tras-os-Montes Zone from central and NW Iberia contribute to constrain the timing of the Cambro-Ordovician magmatism from Central Iberian and Galicia Tras-os-Montes Zones which occurred between 498 and 462 Ma. The crystallization ages of the metagranites and metavolcanic rocks from the northern Schist-Graywacke Complex Domain are as follows: (a) in west Salamanca, 489 ± 5 Ma for Vitigudino, 486 ± 6 Ma for Fermoselle and 471 ± 7 Ma for Ledesma; (b) in northern Gredos, 498 ± 4 Ma for Castellanos, 492 ± 4 Ma for San Pelayo and 488 ± 3 Ma for Bercimuelle; (c) in Guadarrama, 490 ± 5 Ma for La Estación I, 489 ± 9 Ma for La Cañada, 484 ± 6 Ma for Vegas de Matute (leucocratic), 483 ± 6 Ma for El Cardoso, 482 ± 8 Ma for La Morcuera, 481 ± 9 Ma for Buitrago de Lozoya, 478 ± 7 Ma for La Hoya, 476 ± 5 Ma for Vegas de Matute (melanocratic), 475 ± 5 Ma for Riaza, 473 ± 8 Ma for La Estación II and 462 ± 11 Ma for La Berzosa; and (d) in Toledo, 489 ± 7 Ma for Mohares and 480 ± 8 Ma for Polán. The crystallization ages of the metagranites from the Schistose Domain of Galicia Tras-os-Montes Zone are 497 ± 6 Ma for Laxe, 486 ± 8 Ma for San Mamede, 482 ± 7 Ma for Bangueses, 481 ± 5 Ma for Noia, 480 ± 10 for Rial de Sabucedo, 476 ± 9 Ma for Vilanova, 475 ± 6 Ma for Pontevedra, 470 ± 6 Ma for Cherpa and 462 ± 8 Ma for Bande. This magmatism is characterized by an average isotopic composition of (87Sr/86Sr)485Ma ≈ 0.712, (ɛNd)485Ma ≈ -4.1 and (TDM) ≈ 1.62 Ga, and a high zircon inheritance, composed of Ediacaran-Early Cambrian (65 %) and, to a lesser extent, Cryogenian, Tonian, Mesoproterozoic, Orosirian and Archean pre-magmatic cores. Combining our geochronological and isotopic data with others of similar rocks from the European Variscan Belt, it may be deduced that Cambro-Ordovician magmas from this belt were mainly

  17. The lagos La Plata and Fontana fold-and-thrust belt: long-lived orogenesis at the edge of western Patagonia

    Science.gov (United States)

    Folguera, Andrés; Iannizzotto, Noelia F.

    2004-04-01

    Extensive fieldwork carried out in the inner sectors of the Cordillera Patagónica has revealed evidence of alternate of periods of crustal extension and orogen formation since the Jurassic. The Patagonian lithosphere was extended during the Mesozoic and fractured and collapsed into numerous depocenters within the arc and retroarc. The last pulse of extension during this period occurred in the Early Cretaceous, related to a series of Pacific transgressions that formed the embayment of the Rı´o Mayo basin, north of the Austral basin. The Rı´o Mayo basin is part of a widespread Early Cretaceous synrift episode found throughout the Patagonian region between 155 and 140 Ma. The last part of this rifting episode, between 140 and 125 Ma, was spatially more limited, restricted to the arc and inner retroarc. The area of extension can be related to an early Paleozoic suture between the Somuncura Massif and the hanging wall of the Deseado Massif. The correct identification of this suture zone helps delimit distinctive volcanic provinces, as well as metallogenic ore districts. Thermal subsidence ceased as a consequence of a sudden tectonic inversion related to a major lithospheric reorganization at 120 Ma, during the breakup of southern Gondwana. The closure of the small Rı´o Mayo intra-arc-retroarc basin occurred as a result of a fold-and-thrust belt, mainly by tectonic inversion of previous normal faults, and was partially related to thin-skinned deformation. The emplacement of the Eastern Patagonian batholith between 100 and 80 Ma destroyed the inner sectors of the fold-and-thrust belt. During this time, the collapse of the inner sectors allowed for the development of a second, more limited intra-arc basin. The orogenic wedge grew through the inversion of progressively deeper decollements and out-of-sequence thrusts and lasted until the Late Paleogene, with a period of probable quiescence during the highly oblique subduction of the Aluk (Phoenix) Plate in the early

  18. A Holocene speleothem record from Morocco, NW Africa

    Science.gov (United States)

    Wassenburg, Jasper; Fietzke, Jan; Richter, Detlev; Immenhauser, Adrian

    2010-05-01

    A well dated Holocene speleothem (stalagmite) from the Middle Atlas Mountains in Morocco has been investigated for its continental climate record. The aim is to compile an improved understanding of the climatically complex triple point of the North Atlantic, Mediterranean and Saharan / Monsoonal climate realms in NW Africa. At present, only few studies concerning continental climate reconstructions from NW Africa have been published (Lamb et al. 1995, Cheddadi et al. 1998, Genty et al. 2006). Given the significance of this region, this lack of data forms a strong motivation for additional, well dated climate records. The speleothem (GP2) was sampled in the 'Grotte de Piste' (ca 800 m above sea level), mean annual precipitation is about 930 mm (mainly falling in the winter season) and the mean annual temperature is about 13° C. GP2 is 60 cm tall and grew - based on U/Th MC-ICP-MS data - continuously between 11.5 kyr BP (early Holocene) and 2.9 kyr BP (late Holocene). X-Ray Diffraction data indicate a mainly aragonitic mineralogy. 'Hendy tests' suggest that CaCO3 precipitation was close to isotopic equilibrium with respect to oxygen isotopes, however kinetic effects might have influenced carbon isotopes. Carbon and oxygen isotope data have been measured along a transect with increments of approximately 1 mm representing a resolution of about 15 yrs. Highly covariant oscillations in δ13C and δ18O with an average cyclicity of about 410 yrs. are observed. These oscillations coincide with macroscopically visible high density and low density layers, possibly reflecting a higher or lower amount of inclusions and perhaps higher and lower growth rates. Geochemical analysis of speloan aragonite is accompanied by cave monitoring that has started in November 2009. Parameters quantified include: drip water parameters, cave air humidity, pCO2 and cave air temperature. Precipitation experiments using watch glasses will also be performed. References Cheddadi, R., Lamb, H. F

  19. The metallogenic role of east-west fracture zones in South America with regard to the motion of lithospheric plates (with an example from Brazil)

    Science.gov (United States)

    Kutina, J.; Carter, William D.; Lopez, F.X.

    1978-01-01

    The role of east-west fracture zones in South America is discussed with regard to global fracturing and the motion of lithospheric plates. A set of major NW-trending lineaments has been derived which show a tendency to be spaced equidistantly and may correspond to a set of east-west fractures in the "pre-drift" position of the South American plate. Statistical analysis of linears in the ERTS-mosaics shows that NW-fractures are also among the most important ones in the Andes region, suggesting that the above major lineaments extend into the basement of the Andes. Some of the old major fractures, trending east-west in the present orientation of South America, are discussed and their NE orientation in the pre-drift position of the plate is considered. An example of structural control of ore deposition in the Brazilian Shield is presented, using the maps of the RADAM Project. It is concluded that the small tin-bearing granitic bodies concentrated in the region of Sao Felix do Xingu in the state of Para represent upper parts of an unexposed granitoid massif which is controlled by the intersection of a major east-west fracture zone probably represents westward extension of the Patos Lineament of the easternmost part of Brazil, connected with the east-west fracture zone of the Para state through the basement of the Maranhao Basin (Sineclise do Maranhao-Piaui). It is expected that the proposed "Patos-Para Lineament" extends further westward and may similarly control, at intersections with fractures of other trends, some mineralization centers in the western part of the state of Para and in the state of Amazonas.

  20. Oscillations control of a transmission belt by Excitation Clipping using Clutch Clamping Control (E4C)

    Science.gov (United States)

    Temporelli, Robin; Micheau, Philippe

    2017-04-01

    A transmission belt deals with non-linear phenomena such as parametric excitations that can bring the belt in an instability region resulting in large transverse oscillations. These oscillations can cause belt life deflection, noise and unexpected vibration on its environment. The present study proposes a new strategy to control oscillations of a transmission belt subject to periodic tension fluctuations. Indeed, for a transmission belt, periodic torque fluctuations cause periodic belt tension fluctuations which can be a source of excitation for the belt and resulting in belt oscillations under certain conditions. The presence of a clutch between the belt end-point and the source of torque fluctuations offers a means to clip torque fluctuations and thus to clip belt excitation. In keeping with this notion, belt oscillations can be controlled by an Excitation Clipping using Clutch Clamping Control (E4C) strategy. Through an example of a transmission belt subject to periodic tension fluctuations, the E4C strategy is presented and a new analytical model of belt behavior with its E4C strategy is constructed. Free belt oscillations (E4C is not activated) and controlled belt oscillations (E4C is activated) are observed through an experimental setup and predicted owing to the new analytical model. Finally, the E4C strategy leads to frequency unlocking that successfully removes belt oscillations. This new analytical model furthermore provides an accurate prediction of belt behavior with its E4C strategy.

  1. Geological Characteristics, Metallogenic Regularities and Prospecting Direction of Hukeng Tungsten Deposit%浒坑钨矿床地质特征、成矿规律以及找矿方向

    Institute of Scientific and Technical Information of China (English)

    周孝满; 韩顿

    2013-01-01

    Hukeng tungsten deposit is jointly controlled by the regional fracture, granite strains and its surrounding rock. Regional structure controls the stock emplacement and expand ore fissure. Tungsten-containing quartz vein mainly occurs in the contact area within 300-500 meters into the deep rock mass in the contact zone, which is close to the vertical interface with sectional rear type arrangement. Geological characteristics and metallogenic regulations are analyzed based on the related data, exploration results and mining practice. Based on comprehensive analysis of metallogenic conditions and prospecting results, this paper suggests that good ore prospects exist around the edges of the inner and outer contact zones of granite body.%浒坑钨业是一个开采60年的老矿山,矿床受区域断裂与花岗岩株及其围岩的联合控制。区域构造一方面控制浒坑岩株的侵位,另一方面拓展容矿裂隙。含钨石英矿脉主要赋存于自接触面往岩体深处300~500 m内接触带中,近于垂直接触面发育,在剖面上呈后侧式排列。根据前人的有关资料和浒坑钨矿床近年来勘查成果和采矿实践,分析总结出矿床地质特征和成矿规律新认识。最后,在综合分析成矿条件和找矿成果的基础上,指出围绕浒坑花岗岩体边缘内外接触带,有较好找矿前景。

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

    Institute of Scientific and Technical Information of China (English)

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

    2006-01-01

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

  3. CRED REA Algal Assessments at Necker, NW Hawaiian Islands in 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines, as part of Rapid Ecological Assessments, conducted at 2 sites at Necker in the NW...

  4. CRED REA Fish Team Stationary Point Count Surveys at Laysan, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Stationary Point Counts at 4 stations at each survey site were surveyed as part of Rapid Ecological Assessments (REA) conducted at 3 sites around Laysan in the NW...

  5. CRED REA Algal Assessments at Kure Atoll, NW Hawaiian Islands in 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines, as part of Rapid Ecological Assessments, conducted at 9 sites at Kure Atoll in the NW...

  6. CRED REA Algal Assessments at Lisianski, NW Hawaiian Islands in 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines, as part of Rapid Ecological Assessments, conducted at 9 sites at Lisianski in the NW...

  7. CRED REA Algal Assessments at Maro Reef, NW Hawaiian Islands in 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines, as part of Rapid Ecological Assessments, conducted at 9 sites at Maro Reef in the NW...

  8. CRED REA Algal Assessments at Midway, NW Hawaiian Islands in 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines, as part of Rapid Ecological Assessments, conducted at 9 sites at Midway in the NW...

  9. CRED REA Fish Team Stationary Point Count Surveys at Maro Reef, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Stationary Point Counts at 4 stations at each survey site were surveyed as part of Rapid Ecological Assessments (REA) conducted at 9 sites around Maro Reef in the NW...

  10. CRED REA Fish Team Stationary Point Count Surveys at Midway, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Stationary Point Counts at 4 stations at each survey site were surveyed as part of Rapid Ecological Assessments (REA) conducted at 9 sites around Midway in the NW...

  11. CRED REA Algal Assessments at Laysan, NW Hawaiian Islands in 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines, as part of Rapid Ecological Assessments, conducted at 3 sites at Laysan in the NW...

  12. Re-Os pyrite geochronology of Zn-Pb mineralization in the giant Caixiashan deposit, NW China

    Science.gov (United States)

    Li, Dengfeng; Chen, Huayong; Hollings, Pete; Zhang, Li; Mi, Mei; Li, Jie; Fang, Jing; Wang, Chengming; Lu, Wanjian

    2016-03-01

    The newly discovered Caixiashan Irish-type Zn-Pb deposit (˜131 Mt at 3.95 % Zn + Pb), located in the Eastern Tianshan of Xinjiang, is one of the largest Zn-Pb deposits in NW China. Massive colloform/framboidal textured syn-sedimentary pyrite yielded a Re-Os isochron age of 1019 ± 70 Ma (MSWD = 3.5), which is interpreted to be the depositional age of the Kawabulake group that hosts the ore. The age of the main mineralization stage is constrained by two types of pyrite: the layered pyrite coexists with recrystallized calcite and dolomite and is locally replaced by sphalerite, whereas the euhedral pyrite occurs with galena that crosscuts the massive sphalerite. The layered pyrite yielded a Re-Os age of 859 ± 79 Ma (MSWD = 6.7; initial 187Os/188Os ratio [IOs] = 0.19 ± 0.25) and the euhedral pyrite 837 ± 39 Ma (MSWD = 6.5; [IOs] = 0.16 ± 0.09), which are interpreted to be the Zn and Pb mineralization ages, respectively. The low radiogenic initial Os values of the Zn-Pb mineralization suggest interaction between a hydrothermal fluid and a mafic or ultramafic source rock with a mantle Os signature with some contamination with Mesoproterozoic Kawabulake group. Based on our new Re-Os ages, we conclude that the giant Caixiashan Zn-Pb deposit formed in the early Neoproterozoic and it represents a newly identified mineralization epoch in the Eastern Tianshan of the Central Asia Orogenic Belt.

  13. Geochemistry of Archean metasedimentary rocks of the Aravalli craton, NW India: Implications for provenance, paleoweathering and supercontinent reconstruction

    Science.gov (United States)

    Ahmad, Iftikhar; Mondal, M. E. A.; Satyanarayanan, M.

    2016-08-01

    Basement complex of the Aravalli craton (NW India) known as the Banded Gneissic Complex (BGC) is classified into two domains viz. Archean BGC-I and Proterozoic BGC-II. We present first comprehensive geochemical study of the Archean metasedimentary rocks occurring within the BGC-I. These rocks occur associated with intrusive amphibolites in a linear belt within the basement gneisses. The association is only concentrated on the western margin of the BGC-I. The samples are highly mature (MSm) to very immature (MSi), along with highly variable geochemistry. Their major (SiO2/Al2O3, Na2O/K2O and Al2O3/TiO2) and trace (Th/Sc, Cr/Th, Th/Co, La/Sc, Zr/Sc) element ratios, and rare earth element (REE) patterns are consistent with derivation of detritus from the basement gneisses and its mafic enclaves, with major contribution from the former. Variable mixing between the two end members and closed system recycling (cannibalism) resulted in the compositional heterogeneity. Chemical index of alteration (CIA) of the samples indicate low to moderate weathering of the source terrain in a sub-tropical environment. In A-CN-K ternary diagram, some samples deceptively appear to have undergone post-depositional K-metasomatism. Nevertheless, their petrography and geochemistry (low K2O and Rb) preclude the post-depositional alteration. We propose non-preferential leaching of elements during cannibalism as the cause of the deceptive K-metasomatism as well as enigmatic low CIA values of some highly mature samples. The Archean metasedimentary rocks were deposited on stable basement gneisses, making the BGC-I a plausible participant in the Archean Ur supercontinent.

  14. Geochronology and geochemistry of the high Mg dioritic dikes in Eastern Tianshan, NW China: Geochemical features, petrogenesis and tectonic implications

    Science.gov (United States)

    Li, Deng-Feng; Zhang, Li; Chen, Hua-Yong; Hollings, Pete; Cao, Ming-Jian; Fang, Jing; Wang, Cheng-Ming; Lu, Wan-Jian

    2016-01-01

    Zircon U-Pb ages of high Mg dioritic dikes in the Mesoproterozoic Kawabulake Group in the Eastern Tianshan area, NW China indicate that they were emplaced in the Early Carboniferous at 353-348 Ma. The dikes consist of medium-grained plagioclase and hornblende with minor clinopyroxene and trace quartz. They are characterized by intermediate SiO2 (60-62 wt.%), low TiO2 (0.63-0.71 wt.%), relatively high Al2O3 (15.1-15.8 wt.%) and MgO contents (3.45-4.15 wt.%) with Mg# generally higher than 56 (56-59). The geochemistry of the high Mg diorites suggest they were formed by similar magmatic processes to sanukitoid high Mg Andesites such as those of the Setouchi volcanic belt, Japan. Zircons from the high Mg dioritic dikes have εHf(t) values of -6.8 to +14.5. The dominantly positive values suggest a juvenile source, whereas the small number of negative values suggests mature components were also incorporated into the source. Similarly, the positive εNd(t) values (0 to +2.2) are interpreted to reflect a juvenile source whereas the negative values of (-5.2 to 0) suggest participation of old crustal rocks in the petrogenesis of the diorites. The variable εHf(t) and εNd(t) values suggest that the mature material was assimilated during magma ascent rather than in the mantle wedge which would result in more uniform values. Mass balance calculations suggest that the dioritic dikes were derived from sources composed of approximately 97% juvenile mantle-derived material and 3% sediment. Petrographic, elemental, and isotopic evidence suggest that the dioritic dikes were generated by partial melting of depleted mantle that migrated into the shallow crust where it assimilated older sedimentary rocks of the Mesoproterozoic Kawabulake Group.

  15. Comparative study of Uranium estimation in drinking water samples of seismically active regions of NW-Himalayas, Himachal Pradesh and SW-Punjab, India using Laser Fluorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bajwa, B.; Arora, V.; Saini, K. [Guru Nanak Dev University, Amritsar (India)

    2014-07-01

    The Laser Fluorimetry Technique has been used for the microanalysis of uranium content in drinking water samples collected from different sources like the hand pumps and natural springs of seismically active regions of Chamba and Dharamshala, Himachal Pradesh, NW-Himalayas and Bathinda and Mansa districts of SW-Punjab, state, India. The purpose of this study was to investigate the uranium concentration levels of ground water being used for drinking purposes and to determine its health effects, if any, to the local population of these regions. In the present study 47 samples of drinking water collected from different villages of the seismic active belt of Chamba and Dharamshala region of Himachal Pradesh, India have been analyzed for chemical and radiological toxicity. Uranium concentration in drinking water sample of study region ranged between 2.7 μgL{sup -1} - 53.9 μgL{sup -1} with an average value of 20.1 μgL{sup -1}. In SW-Punjab, Uranium concentration in 76 drinking water samples has been found to vary between 0.13 μgL{sup -1} and 676 μgL{sup -1} with an average of 90.2 μgL{sup -1}. Data analysis reveals that, 19% samples of NW-Himalayas water have uranium concentration higher than recommended limit of 30 μgL{sup -1} (WHO, 2011) while none of the samples exceeds the threshold of 60 μgL{sup -1} recommended by AERB, DAE, India, 2004. On the other hand, 64% water samples of SW-Punjab have uranium concentration higher than recommended limit of 30 μgL{sup -1} (WHO, 2011) while 39% water samples exceeds the threshold of 60 μgL{sup -1} recommended by AERB, DAE, India, 2004. Document available in abstract form only. (authors)

  16. Methane emissions from the upwelling area off Mauritania (NW Africa

    Directory of Open Access Journals (Sweden)

    A. Kock

    2008-08-01

    Full Text Available Coastal upwelling regions have been identified as sites of enhanced CH4 emissions to the atmosphere. The coastal upwelling area off Mauritania (NW Africa is one of the most biologically productive regions of the world's ocean but its CH4 emissions have not been quantified so far. More than 1000 measurements of atmospheric and dissolved CH4 in the surface layer in the upwelling area off Mauritania were performed as part of the German SOPRAN (Surface Ocean Processes in the Anthropocene study during two cruises in March/April 2005 (P320/1 and February 2007 (P348. During P348 enhanced CH4 saturations of up to 200% were found close to the coast and were associated with upwelling of South Atlantic Central Water. An area-weighted, seasonally adjusted estimate yielded overall annual CH4 emissions in the range from 1.6 to 2.9 Gg CH4. Thus the upwelling area off Mauritania represents a regional hot spot of CH4 emissions but seems to be of minor importance for the global oceanic CH4 emissions.

  17. Eruptive Variable Stars and Outflows in Serpens NW

    CERN Document Server

    Hodapp, Klaus W; Watermann, Ramon; Lemke, Roland

    2011-01-01

    We study the outflow activity, photometric variability and morphology of three very young stellar objects in the Serpens NW star forming region: OO Serpentis, EC 37 (V370 Ser) and EC 53 (V371 Ser). High spatial resolution Keck/NIRC2 laser guide star adaptive optics images obtained in 2007 and 2009 in broad-band K and in a narrow-band filter centered on the 1-0 S(1) emission line of molecular hydrogen allow us to identify the outflows from all three objects. We also present new, seeing-limited data on the photometric evolution of the OO Ser reflection nebula and re-analyze previously published data. We find that OO Ser declined in brightness from its outburst peak in 1995 to about 2003, but that this decline has recently stopped and actually reversed itself in some areas of the reflection nebula. The morphology and proper motions of the shock fronts MHO 2218 near EC 37 suggest that they all originate in EC 37 and that this is an outflow seen nearly along its axis. We identify a molecular hydrogen jet emerging ...

  18. North Florida is part of the stroke belt.

    OpenAIRE

    Siegel, P. Z.; Wolfe, L E; Wilcox, D.; Deeb, L C

    1992-01-01

    Florida is the only State in the southeastern United States that is not part of the "stroke belt." The National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health, defines the stroke belt as those States with an age-adjusted stroke mortality rate for the years 1979 to 1981 that is more than 10 percent above the national annual rate of 40.3 per 100,000 population. By reproducing at the county level the methods that were used at the State level to describe the stroke belt, ...

  19. Radiation Belt Storm Probes: Resolving Fundamental Physics with Practical Consequences

    Science.gov (United States)

    Ukhorskiy, Aleksandr Y.; Mauk, Barry H.; Fox, Nicola J.; Sibeck, David G.; Grebowsky, Joseph M.

    2011-01-01

    The fundamental processes that energize, transport, and cause the loss of charged particles operate throughout the universe at locations as diverse as magnetized planets, the solar wind, our Sun, and other stars. The same processes operate within our immediate environment, the Earth's radiation belts. The Radiation Belt Storm Probes (RBSP) mission will provide coordinated two-spacecraft observations to obtain understanding of these fundamental processes controlling the dynamic variability of the near-Earth radiation environment. In this paper we discuss some of the profound mysteries of the radiation belt physics that will be addressed by RBSP and briefly describe the mission and its goals.

  20. Human neuronal interlimb coordination during split-belt locomotion

    OpenAIRE

    Dietz, V; Zijlstra, W G; Duysens, J.E.J.

    1994-01-01

    Human interlimb coordination and the adaptations in leg muscle activity were studied during walking on a treadmill with split belts. Four different belt speeds (0.5, 1.0, 1.5, 2.0 m/s) were offered in all possible combinations for the left and right leg. Subjects adapted automatically to a difference in belt speed within 10–20 stride cycles.This adaptation was achieved by a reorganization of the stride cycle with a relative shortening of the duration of the support and lengthening of the swin...

  1. Resistance and other parameters of belt conveyor shifting

    Energy Technology Data Exchange (ETDEWEB)

    Dembinski, M.

    1988-07-01

    Discusses a method developed by Poltegor for calculating energy consumption of belt conveyor shifting in brown coal surface mines in Poland. A program for simulating effects of all significant factors that represent the environment, physical and mechanical properties of soil, effects of weather and atmospheric precipitations, design of belt conveyors, effects of soil or coal buildup and conveyor wear is used. Indices that describe effects of major groups of factors are used for calculating resistance to belt conveyor shifting considering local conditions. Investigations carried out in the Belchatow brown coal mine show the method to be accurate and reliable.

  2. Power Transmission Through Timing Belt In Two Wheeler Motors

    Directory of Open Access Journals (Sweden)

    Gurumurthy Veerapathiran

    2015-03-01

    Full Text Available This paper studies the effect of noise and friction on performance of the chain drive system for motor bikes. Experiment shows that chain transmission in chain drive system leads to poor overall performance, due to its noise and chain gets loose due to aging and sprockets wear due to chain friction etc., the proposed system consists of drive and driven pulley with timing belt transmission. Compared to conventional method, proposed method give improved tension in pulleys and belt by the additional arrangement called belt tensioner. This gives good overall performance of the system, and reduces noise, vibration and gives high transmission speed.

  3. Characterising the nature, evolution and origin of detachment fault in central depression belt, Qiongdongnan Basin of South China Sea:evidence from seismic reflection data

    Institute of Scientific and Technical Information of China (English)

    REN Jianye; YANG Linlong; ZHANG Daojun; TONG Dianjun; HUANG Anmin; WANG Yahui; LEI Chao; ZUO Qianmei; ZHAO Yanghui; HE Weijun

    2014-01-01

    Using regional geological, newly acquired 2D and 3D seismic, drilling and well log data, especially 2D long cable seismic profiles, the structure and stratigraphy in the deep-water area of Qiongdongnan Basin are interpreted. The geometry of No.2 fault system is also re-defined, which is an important fault in the central depression belt of the deep-water area in the Qiongdongnan Basin by employing the quantitative analysis techniques of fault activity and backstripping. Furthermore, the dynamical evolution of the No.2 fault sys-tem and its controls on the central depression belt are analyzed. This study indicates that the Qiongdongnan Basin was strongly influenced by the NW-trending tensile stress field during the Late Eocene. At this time, No.2 fault system initiated and was characterized by several discontinuous fault segments, which controlled a series small NE-trending fault basins. During the Oligocene, the regional extensional stress field changed from NW-SE to SN with the oceanic spreading of South China Sea, the early small faults started to grow along their strikes, eventually connected and merged as the listric shape of the No.2 fault system as ob-served today. No.2 fault detaches along the crustal Moho surface in the deep domain of the seismic profiles as a large-scale detachment fault. A large-scale rollover anticline formed in hanging wall of the detachment fault. There are a series of small fault basins in both limbs of the rollover anticline, showing that the early small basins were involved into fold deformation of the rollover anticline. Structurally, from west to east, the central depression belt is characterized by alternatively arranged graben and half-graben. The central depression belt of the Qiongdongnan Basin lies at the extension zone of the tip of the V-shaped northwest-ern ocean sub-basin of the South China Sea, its activity period is the same as the development period of the northwestern ocean sub-basin, furthermore the emplacement and

  4. ECONOMIC GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20110164 Dong Lianhui(Xinjiang Bureau of Geology and Mineral Resources and Development,Urumqi 830000,China);Feng Jing Research for Classification of Metallogenic Unit of Xinjiang(Xinjiang Geology,ISSN1000-8845,CN65-1092/P,28(1),2010,p.1-15,1 illus.,1 table,17 refs.,with English abstract)Key words:metallogenic provinces,metallogenic belts,metallogenic area,Xinjiang

  5. Effect of one-way clutch on the nonlinear vibration of belt-drive systems with a continuous belt model

    Science.gov (United States)

    Ding, Hu; Zu, Jean W.

    2013-11-01

    This study focuses on the nonlinear steady-state response of a belt-drive system with a one-way clutch. A dynamic model is established to describe the rotations of the driving pulley, the driven pulley, and the accessory shaft. Moreover, the model considers the transverse vibration of the translating belt spans for the first time in belt-drive systems coupled with a one-way clutch. The excitation of the belt-drive system is derived from periodic fluctuation of the driving pulley. In automotive systems, this kind of fluctuation is induced by the engine firing harmonic pulsations. The derived coupled discrete-continuous nonlinear equations consist of integro-partial-differential equations and piece-wise ordinary differential equations. Using the Galerkin truncation, a set of nonlinear ordinary differential equations is obtained from the integro-partial-differential equations. Applying the Runge-Kutta time discretization, the time histories of the dynamic response are numerically solved for the driven pulley and the accessory shaft and the translating belt spans. The resonance areas of the coupled belt-drive system are determined using the frequency sweep. The effects of the one-way clutch on the belt-drive system are studied by comparing the frequency-response curves of the translating belt with and without one-way clutch device. Furthermore, the results of 2-term and 4-term Galerkin truncation are compared to determine the numerical convergence. Moreover, parametric studies are conducted to understand the effects of the system parameters on the nonlinear steady-state response. It is concluded that one-way clutch not only decreases the resonance amplitude of the driven pulley and shaft's rotational vibration, but also reduces the resonance region of the belt's transverse vibration.

  6. Trio of Neptunes and their Belt

    Science.gov (United States)

    2006-05-01

    Using the ultra-precise HARPS spectrograph on ESO's 3.6-m telescope at La Silla (Chile), a team of European astronomers have discovered that a nearby star is host to three Neptune-mass planets. The innermost planet is most probably rocky, while the outermost is the first known Neptune-mass planet to reside in the habitable zone. This unique system is likely further enriched by an asteroid belt. ESO PR Photo 18a/06 ESO PR Photo 18a/06 Planetary System Around HD 69830 (Artist's Impression) "For the first time, we have discovered a planetary system composed of several Neptune-mass planets", said Christophe Lovis, from the Geneva Observatory and lead-author of the paper presenting the results [1]. During more than two years, the astronomers carefully studied HD 69830, a rather inconspicuous nearby star slightly less massive than the Sun. Located 41 light-years away towards the constellation of Puppis (the Stern), it is, with a visual magnitude of 5.95, just visible with the unaided eye. The astronomers' precise radial-velocity measurements [2] allowed them to discover the presence of three tiny companions orbiting their parent star in 8.67, 31.6 and 197 days. "Only ESO's HARPS instrument installed at the La Silla Observatory, Chile, made it possible to uncover these planets", said Michel Mayor, also from Geneva Observatory, and HARPS Principal Investigator. "Without any doubt, it is presently the world's most precise planet-hunting machine" [3]. ESO PR Photo 18d/06 ESO PR Photo 18d/06 Phase Folded Measurements of HD 69830 The detected velocity variations are between 2 and 3 metres per second, corresponding to about 9 km/h! That's the speed of a person walking briskly. Such tiny signals could not have been distinguished from 'simple noise' by most of today's available spectrographs. The newly found planets have minimum masses between 10 and 18 times the mass of the Earth. Extensive theoretical simulations favour an essentially rocky composition for the inner planet, and

  7. 30 CFR 57.14131 - Seat belts for surface haulage trucks.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Seat belts for surface haulage trucks. 57.14131... and Equipment Safety Devices and Maintenance Requirements § 57.14131 Seat belts for surface haulage trucks. (a) Seat belts shall be provided and worn in haulage trucks. (b) Seat belts shall be...

  8. Practical and medical aspects of the use of car seat belts.

    NARCIS (Netherlands)

    Edelman, A. & Kampen, L.T.B. van

    1974-01-01

    An analysis is made of the influence of use and non-use of seat belts on type and severity of injuries to drivers and of the influence of seat belt type on type and severity of injuries to drivers. Users of lap belts and users of 3-point belts enjoy a comparable and considerable reduction of injury

  9. MACRO MODEL OF SEAT BELT USE BY CAR DRIVERS AND PASSENGERS

    Directory of Open Access Journals (Sweden)

    Kazimierz JAMROZ

    2013-12-01

    Full Text Available The article presents some problems of seat belt use by car drivers and passengers. It looks in particular at seat belt use and effectiveness in selected countries. Next, factors of seat belt use are presented and methodology of model development. A macro model of seat belt use is presented based on data from around fifty countries from different continents.

  10. Feasibility of electro-osmotic belt filter dewatering technology at pilot scale

    CSIR Research Space (South Africa)

    Snyman, HG

    2000-01-01

    Full Text Available -effective dewatering technologies, electro-osmotic belt filtering was developed by Smollen and Kafaar in 1995. The mechanical equipment resembles a belt filter press but the belts are stainless steel, woven belts, which act as the electrodes. In this study...

  11. Controls on dryland mountain landscape development along the NW Saharan desert margin: Insights from Quaternary river terrace sequences (Dadès River, south-central High Atlas, Morocco)

    DEFF Research Database (Denmark)

    Stokes, M.; Mather, A.E.; Belfoul, M.

    2017-01-01

    between 50 and 140 m. The rock strength, stratigraphy and structure of the mountain belt influences terrace distribution. Terraces are absent in river gorges of structurally thickened limestone; whilst well-developed, laterally continuous terraces (T1-T4) form along wide valleys occupying syncline...... sands and colluvium. This sequence with some OSL/IRSL age control, suggests terrace formation over a 100 ka climate cycle with valley floor aggradation during full glacials and incision during glacial-interglacial transitions. This integrates with other archives (e.g. lakes, glaciers, dunes), appearing...... typical of landscape development along the NW Saharan margin south of the High Atlas, and similar to patterns in the western-southern Mediterranean. The 100 ka climate cycle relationship suggests that the terrace sequence documents Late-Middle Pleistocene landscape development. Consistent altitudinal...

  12. FORMATION AND EVOLUTION OF THE CENOZOIC THRUST FOLD BELT IN JINPING, SICHUAN

    Institute of Scientific and Technical Information of China (English)

    LIAO Zhongli; DENG Yongfu; LIAO Guangyu

    2003-01-01

    The Jinping orogenic belt in Sichuan, China consists mainly of the Jinpingshan intracontinental thrust-nappe belt, foreland thrust-nappe belt and foreland uplift belt. Based on analyses about the characteristics of the structural units in this area, the authors propose in this paper that Chapuzi-Bazhe revival fault belt is the regional boundary fault, and points out that after the formation of the Pre-Sinian basement, the western edge of the Yangtze paraplatform was turned into the passive continental margin in Sinian to Triassic, then into the Mesozoic collision orogenic belt, and finally into the Cenozoic orogenic belt through intracontinental orogeny.

  13. "Abomination"--life as a Bible belt gay.

    Science.gov (United States)

    Barton, Bernadette

    2010-01-01

    Drawing on observation, autoethnography, and audio-taped interviews, this article explores the religious backgrounds and experiences of Bible Belt gays. In the Bible Belt, Christianity is not confined to Sunday worship. Christian crosses, messages, paraphernalia, music, news, and attitudes permeate everyday settings. Consequently, Christian fundamentalist dogma about homosexuality-that homosexuals are bad, diseased, perverse, sinful, other, and inferior-is cumulatively bolstered within a variety of other social institutions and environments in the Bible Belt. Of the 46 lesbians and gay men interviewed for this study (age 18-74 years), most describe living through spirit-crushing experiences of isolation, abuse, and self-loathing. This article argues that the geographic region of the Bible Belt intersects with religious-based homophobia. Informants explained that negative social attitudes about homosexuality caused a range of harmful consequences in their lives including the fear of going to hell, depression, low self-esteem, and feelings of worthlessness.

  14. Back belts in occupational setting: what are the evidences?

    Directory of Open Access Journals (Sweden)

    João Marcos Bernardes

    2012-01-01

    Full Text Available Although, widely used the mechanisms of action and the effectiveness of back belts in the prevention of occupational low back disorders remains uncertain, generating controversy about its use. Therefore, the purpose of this study was to do a critical literature review about back belts use in the prevention of occupational low back pain in the occupational setting. In order to do that, a bibliographic research in the following data basis: Medline, SciELO and LILACS was conducted. There is evidence that back belts use reduces spine range of motion, however the studies about intra-abdominal pressure and muscle activity presented contradictory results, as the epidemiologic studies, not allowing the recommendation of its use in the prevention of occupational low back pain. Based on this literature review it is suggested therefore, the implementation of new studies, to confirm or not the effectiveness of back belts as personal protective equipment, in the prevention of occupational low back disorders.

  15. Jupiter's radiation belt ions - A comparison of theory and observation

    Science.gov (United States)

    Summers, Danny; Thorne, Richard M.; Mei, YI

    1989-01-01

    Radial profiles are constructed for the Jovian radiation belt flux-tube content Y-asterisk from the reported phase-space density of energetic particles obtained from Voyager 1 data over the range L = 6 to L = 9. These experimental profiles are compared with theoretical solutions for Y-asterisk from an interchange-diffusion model of the coupled radiation belt and Iogenic ion populations. Subject to certain limitations of the Voyager 1 data, the model solutions are found to be consistent with the data for a variety of input parameters. Model solutions are also found corresponding to radiation belt ions that are expected to be mainly responsible for the auroral energy input. Comparison of the present theoretical profiles with the data implies that the energetic radiation belt ions should have a peak loss rate within a factor of three of that for strong diffusion scattering.

  16. CRED REA Fish Team Belt Transect Survey at Laysan 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 3 sites at Laysan in the Northwest...

  17. Periumbilical allergic contact dermatitis: blue jeans or belt buckles?

    Science.gov (United States)

    Byer, Tara T; Morrell, Dean S

    2004-01-01

    Nickel is the most ubiquitous contact allergen among children and adolescents. Metal blue jeans buttons and belts have been noted to cause nickel dermatitis around the umbilicus. For these children, traditional teaching is strict avoidance of all pants with metal snaps/buttons, particularly blue jeans. In this study we tested 90 pairs of blue jeans and 47 belts for nickel using the dimethylglyoxime spot test. Only 10% of blue jeans tested positive, while 53% of belts tested positive. Furthermore, 10 pairs of nickel-negative blue jeans remained negative after 10 washings. Overall we found no resistance to testing in clothing stores. From these results, we recommend that patients with allergic contact dermatitis secondary to nickel need not strictly avoid blue jeans and metal belt buckles. Rather, families should be encouraged to use the dimethylglyoxime spot test to test these items for nickel prior to purchase.

  18. 5m Main Belt Asteroid Population Estimation Using Vesta Imagery

    Science.gov (United States)

    Rynders, Michael; Trilling, David E.

    2016-10-01

    The Main Belt is the largest source of Near-Earth asteroids, but objects 2 pixels in diameter that were counted in a 33km 2 region to give a crater density. By knowing the crater density and making some reasonable assumptions about the orbital distribution of asteroids and the age of Vesta's surface, an estimate of the population of small asteroids in the inner main belt was made. It was found that the inner region of the main asteroid belt contains approximately 20 billion asteroids larger than 5 m. These results agree well with the measured inner Main Belt Size distribution derived by the Wide-field Infrared Survey Explorer, WISE (Masiero et al. 2011).

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

    Science.gov (United States)

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

    2016-04-01

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

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

    Directory of Open Access Journals (Sweden)

    A. Beiranvand Pour

    2016-06-01

    Full Text Available The Bentong-Raub Suture Zone (BRSZ of Peninsular Malaysia is one of the significant structural zones in Sundaland, Southeast Asia. It forms the boundary between the Gondwana-derived Sibumasu terrane in the west and Sukhothai arc in the east. The BRSZ is also genetically related to the sediment-hosted/orogenic gold deposits associated with the major lineaments and form-lines in the central gold belt Central Gold Belt of Peninsular Malaysia. In tropical environments, heavy tropical rainforest and intense weathering makes it impossible to map geological structures over long distances. Advances in remote sensing technology allow the application of Synthetic Aperture Radar (SAR data in geological structural analysis for tropical environments. In this investigation, the Phased Array type L-band Synthetic Aperture Radar (PALSAR satellite remote sensing data were used to analyse major geological structures in Peninsular Malaysia and provide detailed characterization of lineaments and form-lines in the BRSZ, as well as its implication for sediment-hosted/orogenic gold exploration in tropical environments. The major geological structure directions of the BRSZ are N-S, NNE-SSW, NE-SW and NW-SE, which derived from directional filtering analysis to PALSAR data. The pervasive array of N-S faults in the study area and surrounding terrain is mainly linked to the N-S trending of the Suture Zone. N-S striking lineaments are often cut by younger NE-SW and NW-SE-trending lineaments. Gold mineralized trends lineaments are associated with the intersection of N-S, NE-SW, NNW-SSE and ESE-WNW faults and curvilinear features in shearing and alteration zones. Lineament analysis on PALSAR satellite remote sensing data is a useful tool for detecting the boundary between the Gondwana-derived terranes and major geological features associated with suture zone especially for large inaccessible regions in tropical environments.

  1. Structural evolution and U-Pb SHRIMP zircon ages of the Neoproterozoic Maria da Fé shear zone, central Ribeira Belt - SE Brazil

    Science.gov (United States)

    Zuquim, M. P. S.; Trouw, R. A. J.; Trouw, C. C.; Tohver, E.

    2011-03-01

    The Maria da Fé Shear Zone (MFSZ) is a sinistral strike-slip kilometric-scale structure developed in the late Neoproterozoic during the assembly of Gondwana. The MFSZ development is related to the NW-SE collision between the São Francisco Paleocontinent and the Rio Negro Magmatic Arc, which formed the Ribeira Belt. This paper describes the shear zone in detail, concluding that the orientation and age are consistent with NW-SE shortening during the afore mentioned collision. A U-Pb SHRIMP Concordia age of 586.9 ± 8.7 Ma is reported from zircon grains of a granitic dyke that crystallised synkinematically to the main tectonic activity of the shear zone. Another group of zircon grains from the same sample generated an upper intercept age of 2083 ± 43 Ma anchored in the younger Concordia age. These zircon grains are interpreted as relict grains of the basement from which the granite dyke was generated by partial melting. The temperature during mylonitization in the MFSZ was estimated in the range from 450 to 600 °C, based on microstructures in quartz and feldspar. An earlier collision in the same region, between 640 and 610 Ma, led to an extensive nappe-stack with tectonic transport to ENE, integrating the southern Brasilia Belt. One of the thrust zones between these nappes in the studied area is the Cristina Shear Zone with mylonites that were generated under upper amphibolite to granulite facies conditions. Brittle-ductile E-W metric-scale shear zones are superimposed on the MFSZ, which were active in similar, but probably slightly cooler, metamorphic conditions (≈500 °C).

  2. Landscape History of Grosses Moos, NW Swiss Alpine Foreland.

    Science.gov (United States)

    Joanna Heer, Aleksandra; Adamiec, Grzegorz; Veit, Heinz; May, Jan-Hendrik; Novenko, Elena; Hajdas, Irka

    2017-04-01

    woodland clearings in the River Aare Valley and around the Lake Neuchâtel. The development of several dune belts in the study area are attributed to various periods since the Lateglacial, e.g. the turn of the Holocene, the lake level drop in the Mid-Holocene, and the beginning of the Little Ice Age, and can thus be related to surprisingly varied environmental conditions. Despite the eventful past of the Grosses Moos, a Holocene Luvisol has preserved until recently on top of the oldest dune belt called Isleren Dune.

  3. Integrating facies and structural analyses with subsidence history in a Jurassic-Cretaceous intraplatform basin: Outcome for paleogeography of the Panormide Southern Tethyan margin (NW Sicily, Italy)

    Science.gov (United States)

    Basilone, Luca; Sulli, Attilio; Gasparo Morticelli, Maurizio

    2016-06-01

    We illustrate the tectono-sedimentary evolution of a Jurassic-Cretaceous intraplatform basin in a fold and thrust belt present setting (Cala Rossa basin). Detailed stratigraphy and facies analysis of Upper Triassic-Eocene successions outcropping in the Palermo Mts (NW Sicily), integrated with structural analysis, restoration and basin analysis, led to recognize and describe into the intraplatform basin the proximal and distal depositional areas respect to the bordered carbonate platform sectors. Carbonate platform was characterized by a rimmed reef growing with progradational trends towards the basin, as suggested by the several reworked shallow-water materials interlayered into the deep-water succession. More, the occurrence of thick resedimented breccia levels into the deep-water succession suggests the time and the characters of synsedimentary tectonics occurred during the Late Jurassic. The study sections, involved in the building processes of the Sicilian fold and thrust belt, were restored in order to obtain the original width of the Cala Rossa basin, useful to reconstruct the original geometries and opening mechanisms of the basin. Basin analysis allowed reconstructing the subsidence history of three sectors with different paleobathymetry, evidencing the role exerted by tectonics in the evolution of the narrow Cala Rossa basin. In our interpretation, a transtensional dextral Lower Jurassic fault system, WNW-ESE (present-day) oriented, has activated a wedge shaped pull-apart basin. In the frame of the geodynamic evolution of the Southern Tethyan rifted continental margin, the Cala Rossa basin could have been affected by Jurassic transtensional faults related to the lateral westward motion of Africa relative to Europe.

  4. Hydrothermal Mineralization on the Mesoproterozoic Passive Continental Margins of China:A Case Study of the Langshan-Zha'ertaishan Belt, Inner Mongolia, China

    Institute of Scientific and Technical Information of China (English)

    PENG Runmin; ZHAI Yusheng

    2004-01-01

    Most ore-forming characteristics of the Langshan-Zha'ertaishan hydrothermal exhalation belt, which consists of the Dongshengmiao, Huogeqi, Tanyaokou and Jiashengpan large-superlarge Zn-Pb-Cu-Fe sulfide deposits, are most similar to those of Mesoproterozoic SEDEX-type provinces of the world. The characteristics include: (1) All deposits of this type in the belt occur in third-order fault-basins in the Langshan-Zha'ertaishan aulacogen along the northern margin of the North China Platform; (2) these deposits with all their orebodies hosted in the Mesoproterozoic impure dolomite-marble and carbonaceous phyllite (or schists) have an apparent stratabound nature; ores display laminated and banded structures,showing clear depositional features; (3) there is some evidence of syn-sedimentary faulting, which to a certain extent accounts for the temporal and spatial distribution and the size of the orebodies in all deposits and the formation of intrabed conglomerates and breccias; (4) they show lateral and vertical zonation of sulfides; (5) The Cu/(Pb+Zn+Cu) ratio of the large and thick Pb+Zn+Cu orebodies gradually decreases from bottom to top; and (6) barite is interbedded with pyrites and sometimes with sphalerite. However, some characteristics such as the Co/Ni radio of the pyrites, the volcanism, for example, of the Langshan-Zha'ertaishan metallogenic belt, are different from those of the typical SEDEX deposits of the world. The meta-basic volcanic rock in Huogeqi, the sodic bimodal volcanic rocks in the Dongshengmiao and potassic bimodal-volcanic rocks with blastoporphyritic and blasto-glomeroporphyritic texture as well as blasto-amygdaloidal structure in the Tanyaokou deposits have been discovered in the only ore-bearing second formation of the Langshan Group in the past 10 years. The metallogeny of some deposits hosted in the Langshan Group is closely related to syn-sedimentary volcanism based on the following facts: most of the lead isotopes in sphalerite, galena

  5. Design of MGA trajectories for main belt asteroid

    Institute of Scientific and Technical Information of China (English)

    崔祜涛; 乔栋; 崔平远; 栾恩杰

    2003-01-01

    Asteroid exploration is one of the most sophisticated missions currently being investigated. Gravityassist trajectories have proven valuable in interplanetary missions such as the Pioneer, Voyager and Galileo. In this paper, we design interplanetary trajectory for main belt asteroid exploration mission with the Mars gravityassist (MGA) using "pork chop" plots and patched-conic theory and give some initial valuable trajectory parameters on main belt asteroid exploration mission with MGA.

  6. The Role of Plasma in Radiation Belt Loss.

    Science.gov (United States)

    Jahn, J. M.; Bonnell, J. W.; Kurth, W. S.; Millan, R. M.; Goldstein, J.; Jaynes, A. N.; Blake, J. B.; Denton, R. E.

    2015-12-01

    The radiation belts are zones of relativistic electrons encircling the Earth. Their radial structure is controlled by the competition between source and loss processes. Most commonly, a two-belt structure prevails, though a more complicated three-belt structure - an inner belt plus two outer electron belts - have repeatedly been observed. The plasma conditions that enable and enhance loss-facilitating wave activity in the inner magnetosphere are still under discussion. Relativistic electrons have been thought to more easily resonate with electromagnetic ion-cyclotron waves (EMIC) when the total plasma density is large (i.e., in the plasmasphere and plume). However, there is evidence that this interaction may be not as strong as thought, and that instead the field-aligned motion of lower energy ring current ions (up to a few 10's keV) may play a key role. Similarly, the exact influence of large heavy ion (O+) concentrations remains unsettled. We use 2.5+ years of Van Allen Probes observations to study the region of plasmasphere-outer belt overlap (and its vicinity). By now, the Van Allen Probes provide a complete and very dense coverage of the complete magnetosphere inside geosynchronous orbit We focus our interest on understanding the plasma conditions that can favor EMIC wave growth. We investigate the temperature anisotropy A (modified by plasma β) of the warm/hot plasma, and contrast it with the location specifics of the plasmasphere (i.e., very high total density) and the occurrence of high O+ concentrations in the overlap regions with the radiation belt(s). We present both average conditions for all parameters during a variety of geomagnetic conditions, and highlight specific loss and overlap events in an effort to establish favorable plasma conditions for relativistic electron loss during those times.

  7. Trapped radiation belts of saturn: first look.

    Science.gov (United States)

    Fillius, W; Ip, W H; McIlwain, C E

    1980-01-25

    Pioneer 11 has made the first exploration of the magnetosphere and trapped radiation belts of Saturn. Saturn's magnetosphere is intermediate in size between Earth's and Jupiter's, with trapped particle intensities comparable to Earth's. The outer region of Saturn's magnetosphere contains lower energy radiation and is variable with time; the inner region contains higher energy particles. The pitch angle distributions show a remarkable variety of field-aligned and locally mirroring configurations. The moons and especially the rings of Saturn are effective absorbers of trapped particles; underneath the rings, the trapped radiation is completely absorbed. We confirm the discovery of a new ring, called the F ring, a new division, the Pioneer division, and a moon, called 1979 S 2. The latter has probably been seen from Earth. There may be evidence for more bodies like 1979 S 2, but at this stage the interpretation of the data is ambiguous. Using particle diffusion rates, we estimate that the cross-sectional area of the F ring is > 7 x 10(13) square centimeters and that the opacity is > 10(-5). Cosmic-ray albedo neutron decay should be looked into as a source of energetic particles in the inner magnetosphere of Saturn.

  8. Radiation Belt Electron Dynamics: Modeling Atmospheric Losses

    Science.gov (United States)

    Selesnick, R. S.

    2003-01-01

    The first year of work on this project has been completed. This report provides a summary of the progress made and the plan for the coming year. Also included with this report is a preprint of an article that was accepted for publication in Journal of Geophysical Research and describes in detail most of the results from the first year of effort. The goal for the first year was to develop a radiation belt electron model for fitting to data from the SAMPEX and Polar satellites that would provide an empirical description of the electron losses into the upper atmosphere. This was largely accomplished according to the original plan (with one exception being that, for reasons described below, the inclusion of the loss cone electrons in the model was deferred). The main concerns at the start were to accurately represent the balance between pitch angle diffusion and eastward drift that determines the dominant features of the low altitude data, and then to accurately convert the model into simulated data based on the characteristics of the particular electron detectors. Considerable effort was devoted to achieving these ends. Once the model was providing accurate results it was applied to data sets selected from appropriate periods in 1997, 1998, and 1999. For each interval of -30 to 60 days, the model parameters were calculated daily, thus providing good short and long term temporal resolution, and for a range of radial locations from L = 2.7 to 3.9. .

  9. Trapped radiation belts of Saturn - First look

    Science.gov (United States)

    Fillius, W.; Ip, W. H.; Mcilwain, C. E.

    1980-01-01

    Data on the magnetosphere of Saturn obtained with the trapped radiation detector package on board the Pioneer 11 spacecraft is reported. Radiation belt profiles determined by the trapped radiation detectors on Pioneer 10 and 11 indicate that Saturn's magnetosphere is intermediate in size between those of the earth and Jupiter, with particle intensities similar to those of the earth. The outer region of the Saturn magnetosphere is found to contain particles of lower energy than the outer region, being strongly influenced by the time-varying solar wind. The moons and rings of Saturn are observed to be effective absorbers of trapped particles, confirming the discoveries of the F ring, the Pioneer ring division and the moon 1979 S 2. Particle diffusion rates are used to estimate a cross-sectional area of greater than 7 x 10 to the 13th sq cm and an opacity greater than 0.00001 for the F ring. It is suggested that cosmic-ray albedo neutron decay be studied as a possible source of energetic particles in the inner magnetosphere of Saturn.

  10. Politicians and Epidemics in the Bible Belt

    Directory of Open Access Journals (Sweden)

    Geurt Henk Spruyt

    2016-07-01

    Full Text Available The Netherlands has a high vaccination coverage, but due to a concentration of people objecting to vaccination on religious grounds in the Bible belt, several polio and measles epidemics have occurred there in the past. This article analyses how and in what way Dutch politicians responded to parents refusing to have their children vaccinated. First, during these epidemics Members of Parliament mainly addressed written questions of a highly technical or procedural nature to the responsible State Secretary or Minister of Public Health. Secondly, the government always requested advice from an advisory body with regard to matters of health after an epidemic. These reports were opposed to mandatory vaccination mainly by using practical arguments. However, by advocating the idea of strengthening the position of minors in public healthcare these reports contributed to legislation codifying the rights of minors concerning public health. The most important rationale behind this response is the complexity of the issue of mandatory vaccination, because different human rights are involved. On the one hand, mandatory vaccination infringes the constitutional rights to the freedom of thought, conscience and religion and encroaches on parental autonomy. On the other hand, children have a right to physical integrity. To find a way out of this unsolvable dilemma, the government and its advisory bodies mainly used practical arguments against mandatory vaccination.

  11. Orion revisited III. The Orion Belt population

    CERN Document Server

    Kubiak, K; Bouy, H; Sarro, L M; Ascenso, J; Burkert, A; Forbrich, J; Großschedl, J; Hacar, A; Hasenberger, B; Lombardi, M; Meingast, S; Köhler, R; Teixeira, P S

    2016-01-01

    This paper continues our study of the foreground population to the Orion molecular clouds. The goal is to characterize the foreground population north of NGC 1981 and to investigate the star formation history in the large Orion star-forming region. We focus on a region covering about 25 square degrees, centered on the $\\epsilon$ Orionis supergiant (HD 37128, B0\\,Ia) and covering the Orion Belt asterism. We used a combination of optical (SDSS) and near-infrared (2MASS) data, informed by X-ray (\\textit{XMM-Newton}) and mid-infrared (WISE) data, to construct a suite of color-color and color-magnitude diagrams for all available sources. We then applied a new statistical multiband technique to isolate a previously unknown stellar population in this region. We identify a rich and well-defined stellar population in the surveyed region that has about 2\\,000 objects that are mostly M stars. We infer the age for this new population to be at least 5\\, Myr and likely $\\sim10$\\,Myr and estimate a total of about 2\\,500 mem...

  12. Dark nebulae, dark lanes, and dust belts

    CERN Document Server

    Cooke, Antony

    2012-01-01

    As probably the only book of its type, this work is aimed at the observer who wants to spend time with something less conventional than the usual fare. Because we usually see objects in space by means of illumination of one kind or another, it has become routine to see them only in these terms. However, part of almost everything that we see is the defining dimension of dark shading, or even the complete obscuration of entire regions in space. Thus this book is focused on everything dark in space: those dark voids in the stellar fabric that mystified astronomers of old; the dark lanes reported in many star clusters; the magical dust belts or dusty regions that have given so many galaxies their identities; the great swirling 'folds' that we associate with bright nebulae; the small dark feature detectable even in some planetary nebulae; and more. Many observers pay scant attention to dark objects and details. Perhaps they are insufficiently aware of them or of the viewing potential they hold, but also it may be...

  13. Politicians and Epidemics in the Bible Belt

    Directory of Open Access Journals (Sweden)

    Geurt Henk Spruyt

    2016-07-01

    Full Text Available The Netherlands has a high vaccination coverage, but due to a concentration of people objecting to vaccination on religious grounds in the Bible belt, several polio and measles epidemics have occurred there in the past. This article analyses how and in what way Dutch politicians responded to parents refusing to have their children vaccinated. First, during these epidemics Members of Parliament mainly addressed written questions of a highly technical or procedural nature to the responsible State Secretary or Minister of Public Health. Secondly, the government always requested advice from an advisory body with regard to matters of health after an epidemic. These reports were opposed to mandatory vaccination mainly by using practical arguments. However, by advocating the idea of strengthening the position of minors in public healthcare these reports contributed to legislation codifying the rights of minors concerning public health. The most important rationale behind this response is the complexity of the issue of mandatory vaccination, because different human rights are involved. On the one hand, mandatory vaccination infringes the constitutional rights to the freedom of thought, conscience and religion and encroaches on parental autonomy. On the other hand, children have a right to physical integrity. To find a way out of this unsolvable dilemma, the government and its advisory bodies mainly used practical arguments against mandatory vaccination.

  14. The Gould Belt, the de Vaucouleurs-Dolidze Belt, and the Orion Arm

    OpenAIRE

    Bobylev, V. V.; Bajkova, A. T.

    2014-01-01

    Based on masers with measured trigonometric parallaxes, we have redetermined the spatial orientation parameters of the Local (Orion) arm. Using 23 sources (the Gould Belt objects were excluded), we have found that their spatial distribution can be approximated by a very narrow ellipsoid elongated in the direction L_1=77.1+/-2.9^o whose symmetry plane is inclined to the Galactic plane at an angle of 5.6+/-0.2^o. The longitude of the ascending node of the symmetry plane is l_\\Omega=70+/-3^o. A ...

  15. Earthquakes, Uplift, and Landscape Evolution in the NW Himalayas

    Science.gov (United States)

    Shahzad, F.; Mahmood, S.; Gloaguen, R.

    2009-05-01

    The terrain between Main Mantle Thrust to Salt Range Thrust in the NW Himalayas has been characterized by surface and subsurface features with variable tectonic activity. These features show relatively variable tectonic activity, existence of blind faults and basement faulting. In the present study, we use seismological and remote sensing analysis backed by field observations to investigate the relationship between earthquakes, uplift, and landscape evolution. We use nonlinear analysis to understand the earthquake dynamics in relation to surface faults and blind faults. The fractal analysis of the seismicity in three subsurface features of the area is used to characterize the roughness of the faults' surface. We find a high fault surface roughness in the Indus Kohistan Seismic Zone (IKSZ). It is concluded that the area is in the process of being uplifted and landscape is evolving. This evolution is further investigated using a set of geomorphological analyses consisting of extracting a drainage network from digital elevation models (DEM). The extracted streams are analysed using to calculate geomorphic indices and relative uplift rates. These analyses were applied on Indus, Swat, Kabul, Kunhar, Kishanganga, Poonch, Jehlum, Swan and Kurram, Kabul Rivers and their associate tributaries. The analyses provide us with the spatial variation of relative uplift based upon specific streams. We found that the Hazara Kashmir Syntaxis and Nanga Parbat Haramosh Massif are subject to a relatively high uplift. It is observed that the neotectonic activities are linearizing the drainage network from meandering pattern. We analyse the complete drainage texture using fractal dimension and lacunarity analysis. The analysis of the fractal dimension (D) employing box counting methods is calculated with a moving window approach and the lower values of D demonstrate the effect of neotectonic activity. The locations with lower but similar D values are further differentiated using

  16. Firewood Resource Management in Different Landscapes in NW Patagonia

    Directory of Open Access Journals (Sweden)

    Daniela V. Morales

    2017-09-01

    Full Text Available Ecosystems, their components, processes and functions are all subject to management by human populations, with the purpose of adapting the environments to make them more habitable and ensuring the availability and continuity of subsistence resources. Although a lot of work has been carried out on resources of alimentary or medicinal interest, little has been done on associating processes of domestication with firewood extraction, a practice considered to be destructive of the environment. In the arid steppe of NW Patagonia, inhabited and managed for different purposes for a long time by Mapuche-Tehuelche communities, the gathering of combustible plant species has up to the present time played a crucial role in cooking and heating, and work is required to achieve sustainability of this resource. In this study we evaluate whether environments with less landscape domestication are more intensively used for firewood gathering. Using an ethnobiological approach, information was obtained through participant observation, interviews and free listing. The data were examined using both qualitative and quantitative approaches. Twenty-eight firewood species are gathered, both native (75% and exotic (25%. The supply of firewood mainly depends on gathering from the domesticated (10 species, semi-domesticated (17 species and low human intervention landscapes (17 species. In contrast to our hypothesis, average use intensity is similar in all these landscapes despite their different levels of domestication. That is, the different areas are taken advantage of in a complementary manner in order to satisfy the domestic demand for firewood. Neither do biogeographic origin or utilitarian versatility of collected plants vary significantly between the different landscape levels of domestication. Our results show that human landscape domestication for the provision of firewood seems to be a socio-cultural resilient practice, and shed new light on the role of culture in

  17. Petrography, palynology and depositional environment of Gelibolu coals, NW Turkey

    Science.gov (United States)

    Demirtaş, Ferdi; Bozcu, Mustafa; Koşun, Erdal

    2014-05-01

    Upper Oligocene and Miocene coal samples collected from two outcrops in the Gelibolu Peninsula, NW Turkey were analyzed petrographically and palynologically to determine the depositional environment of the coals. Microscopic studies reveal that the studied coal samples from both locations are characterized by high amount of huminite group macerals, ranging from 46 to 78% (mineral-included basis). The prevailing maceral from this group is gelinite (31-65%), it can be easily seen on all studied samples, indicative of high gelification degree of organic matter. Relatively low amount of liptinite (does not exceed 9%) and inertinite (does not exceed 8%) are also observed in the coals. The mineral matter content is variable but generally high, varying from 5 to 37%, as in other Turkish coals and consists mostly of clay minerals, quartz, calcite and pyrite. The mean reflectance values range from 0.502 to 0.564% suggesting that rank of coal is subbituminous (ASTM). The chemical properties of coal including calorific value, volatile matter and fixed carbon content are also in accordance with rank of coal. Facies indices based on maceral ratios (Tissue Preservation Index vs. Gelification Index and ABC ternary diagrams) were used to interpret to depositional environment of coals. Low tissue preservation index (TPI) and high gelification index (GI) values are observed. These indices indicate that the coals deposited in limnic environment. High pH and strongly reducing conditions inferred from the presence of framboidal pyrite and also evidenced by low TPI values. The palynological assembly of the coals dominated by angiosperm pollen and spore, however, gymnosperms were rarely seen. Herbaceous/sedge plants are common in Miocene coal samples.

  18. Timing and Spatial Distribution of Loess in Xinjiang, NW China.

    Directory of Open Access Journals (Sweden)

    Yun Li

    Full Text Available Central Asia is one of the most significant loess regions on Earth, with an important role in understanding Quaternary climate and environmental change. However, in contrast to the widely investigated loess deposits in the Chinese Loess Plateau, the Central Asian loess-paleosol sequences are still insufficiently known and poorly understood. Through field investigation and review of the previous literature, the authors have investigated the distribution, thickness and age of the Xinjiang loess, and analyzed factors that control these parameters in the Xinjiang in northwest China, Central Asia. The loess sediments cover river terraces, low uplands, the margins of deserts and the slopes of the Tianshan Mountains and Kunlun Mountains and are also present in the Ili Basin. The thickness of the Xinjiang loess deposits varies from several meters to 670 m. The variation trend of the sand fraction (>63 μm grain-size contour can indicate the local major wind directions, so we conclude that the NW and NE winds are the main wind directions in the North and South Xinjiang, and the westerly wind mainly transport dust into the Ili basin. We consider persistent drying, adequate regional wind energy and well-developed river terraces to be the main factors controlling the distribution, thickness and formation age of the Xinjiang loess. The well-outcropped loess sections have mainly developed since the middle Pleistocene in Xinjiang, reflecting the appearance of the persistent drying and the present air circulation system. However, the oldest loess deposits are as old as the beginning of the Pliocene in the Tarim Basin, which suggests that earlier aridification occurred in the Tarim Basin rather than in the Ili Basin and the Junggar Basin.

  19. Safinamide: FCE 26743, NW 1015, PNU 151774, PNU 151774E.

    Science.gov (United States)

    2004-01-01

    Safinamide [NW 1015, PNU 151774E; FCE 26743] is a potent anticonvulsant and antiparkinsonian compound that is being developed by Newron Pharmaceuticals in Europe. It has been shown to antagonise the calcium and sodium channels, as well as inhibit monoamine oxidase type-B (MAO-B). Phase III trials for the treatment of Parkinson's disease are underway in Germany and Europe, while phase II trials in patients with epilepsy are ongoing in Italy. Newron Pharmaceuticals was founded at the end of 1998 after Pharmacia & Upjohn announced its worldwide restructuring programme. Newron obtained the rights to safinamide, which Pharmacia Corporation (now Pfizer) had been developing as PNU 151774E. Safinamide was originated by Farmitalia-CarloErba in Italy. Newron now owns all intellectual property associated with the drug.A multinational phase II trial for Parkinson's disease in Europe has shown positive results in slowing the progression of the disease; however, due to the placebo-effect seen in this study, a longer (6-month) phase IIb study is planned for the second quarter of 2003. In July 2003, Newron received an IND from the US FDA authorising a phase I trial to confirm that no dietary restrictions are needed in patients while being treated with safinamide. This study is be conducted in 12 healthy volunteers at the University of Vienna, Austria, and will be followed by efficacy studies in Parkinson's disease in the US. Five phase I trials were completed in April 2001 in Switzerland. Safinamide combines sodium and calcium channel modulatory activity with monoamine oxidase B inhibition.

  20. Deformation and Fluid Flow in the Etendeka Plateau, NW Namibia

    Science.gov (United States)

    Salomon, Eric; Koehn, Daniel; Passchier, Cees; Davis, Jennifer; Salvona, Aron; Chung, Peter

    2014-05-01

    We studied deformation bands in sandstone and breccia veins in overlying basalts of the Etendeka Plateau, NW Namibia, regarding their development and history of fluid flow within. The studied deformation bands can be divided into disaggregation bands and cataclastic bands. The former appear to develop in unsorted sandstone, whereas the latter form in well sorted sandstone. We estimated the porosity of the bands and host rock in thin sections using a simple image analysis software (ImageJ). Results show, that no or only a minor decrease in porosity occur in disaggregation bands, while the porosity in cataclastic bands is decreased by up to 82 % with respect to the host rock. These observations are in agreement with results of existing studies (e.g. Fossen et al., 2007). Hence the cataclastic bands form a seal to fluid flow in the host rock, yet it is observed in outcrops that deformation bands can develop into open fractures which in turn increase the permeability of the rock. Breccia veins in the overlying basalts show intense fracturing where the basalt is locally fractured into elongated chips. Mineral precipitation in these breccia veins indicates a hydrothermal origin of the fluids since the precipitates consist of extremely fine-grained quartz aggregates. Secondary mineralization with large crystals indicates that a long-lived fluid circulation through tubular networks was active at a later stage, which eventually sealed the veins completely. We propose that the Etendeka basalts on top of the sandstone formation produced a localized deformation along deformation bands and heated up fluid below the lavas. At a later stage fluid pressures were either high enough to break through the basalt or fracturing due to ongoing extension produced fluid pathways. References Fossen, H., Schultz, R., Shipton, Z. and Mair, K. (2007). Deformation bands in sandstone: a review. J. Geol. Soc., 164, 755-769.

  1. Miocene to recent extension in NW Sulawesi, Indonesia

    Science.gov (United States)

    Advokaat, Eldert L.; Hall, Robert; White, Lloyd T.; Watkinson, Ian M.; Rudyawan, Alfend; BouDagher-Fadel, Marcelle K.

    2017-10-01

    The Malino Metamorphic Complex (MMC) in the western part of the North Arm of Sulawesi (Indonesia) has previously been suggested to be a metamorphic complex exhumed in the Early - Middle Miocene. This idea was based on limited K-Ar and 40Ar/39Ar age data, but no structural data were presented to provide evidence for the mechanism of exhumation. Here we present new field observations, micro-structural analyses and a revised stratigraphy of NW Sulawesi based on new age data, to provide better constraints on the timing and mechanism of exhumation. The data presented here suggest that the MMC is a metamorphic core complex which underwent lithospheric extension during the Early - Middle Miocene. Although the MMC experienced significant extension, there is no evidence that it was exhumed during this time. There is no contact between the MMC and the Pliocene Ongka Volcanics, contradicting a previously inferred unconformable contact. Pliocene undeformed granitoids intruding the MMC indicate the complex was still at depth during their emplacement. Furthermore, Pliocene and Pleistocene cover sequences do not contain metamorphic detritus. A second phase of extensional uplift was accommodated by brittle faulting from the Late Miocene-Pliocene onwards, during which the MMC was exhumed. This extension is widespread, as indicated by synchronous exhumation of the adjacent Palu Metamorphic Complex in West Sulawesi, and rapid subsidence offshore in Gorontalo Bay. It is linked to northward slab rollback of the southward-subducting Celebes Sea since the Pliocene. GPS data show rapid northward motion of the North Arm of Sulawesi with respect to the Celebes Sea, indicating that this process is ongoing at present day.

  2. Forming the Cold Classical Kuiper Belt in a light Disk

    CERN Document Server

    Shannon, Andrew; Lithwick, Yoram

    2015-01-01

    Large Kuiper Belt Objects are conventionally thought to have formed out of a massive planetesimal belt that is a few thousand times its current mass. Such a picture, however, is incompatible with multiple lines of evidence. Here, we present a new model for the conglomeration of Cold Classical Kuiper belt objects, out of a solid belt only a few times its current mass, or a few percent of the solid density in a Minimum Mass Solar Nebula. This is made possible by depositing most of the primordial mass in grains of size centimetre or smaller. These grains collide frequently and maintain a dynamically cold belt out of which large bodies grow efficiently: an order-unity fraction of the solid mass can be converted into large bodies, in contrast to the ~0.1% efficiency in conventional models. Such a light belt may represent the true outer edge of the Solar system, and it may have effectively halted the outward migration of Neptune. In addition to the high efficiency, our model can also produce a mass spectrum that pe...

  3. The thrust contact between the Canastra and Vazante groups in the Southern Brasília Belt: structural evolution, white mica crystallinity and implications for the Brasiliano orogeny

    Directory of Open Access Journals (Sweden)

    Manuela de Oliveira Carvalho

    Full Text Available ABSTRACT: Two regional thrust-sheets of Neoproterozoic metasedimentary rocks occur in the Southern Brasília Belt, northwest Minas Gerais. The lower one comprises the Vazante Group, that is formed in the studied area, from base to top, by the Serra do Garrote (metapelites interlayered with carbonaceous phyllite, Serra do Poço Verde (beige to pink stromatolitic metadolomite with interlayered greenish slates, Morro do Calcário (gray stromatolitic metadolomite interlayered with gray slates and Serra da Lapa (phyllite with dolarenitic lenses interlayered with slates formations. The upper thrust sheet consists of the Canastra Group (Paracatu formation: laminated sericite phyllites and carbonaceous phyllites interlayered with quartzite. The Braziliano orogeny resulted in four phases of contractional deformation, associated with low-grade metamorphism. The first two (D1 and D2 are ductile, while the third and fourth ones (D3 and D4 are brittle-ductile. D1 developed a slaty S1 cleavage subparallel to the primary layering, with shallow to steep dips to NW. D2 developed a crenulation cleavage (S2 that dips moderately to NW and is associated with tight to isoclinal folds. D3 and D4 phases developed crenulations and open folds and kink bands. S3 dips steeply to NW, while S4 has moderate to steep dips to NE and SW. White mica crystallinity (Kübler index measurements in metapelites indicate that both the Canastra and Vazante groups reached anchizone/epizone conditions, and metamorphic discontinuities along thrusts indicate that the peak of metamorphism is pre or syn-thrusting.

  4. The Pakistan Himalaya: Tectonics at the NW corner of exposed Indian continental crust (Invited)

    Science.gov (United States)

    Dipietro, J. A.

    2009-12-01

    Lithotectonic units in the Himalaya maintain structural continuity from Nepal to Zanskar where they are deformed across a broad, arc-parallel, anticlinorium that plunges northwest such that the Tethyan sequence on the north limb, although truncated by the Indus Suture zone and Ladakh batholith, appears to wrap around the nose of the fold to form the Kashmir Tethys on the south limb. From a wide syn-metamorphic thrust zone in Nepal, the MCT southwest of the Kashmir Tethys narrows to form a late- to post-metamorphic thrust that shallows with the plunge of the anticlinorium. Structural continuity is disrupted by middle Miocene to active transverse fault zones that form the western margins of the Nanga Parbat and Hazara syntaxes (the Raikot-Diamir and Jhelum-Balakot fault zones respectively). It is here that Lesser, Greater, and Tethys Himalayan units lose their identity as defined and understood in the Central Himalaya. Both transverse fault zones are east-side-up and associated with antiforms that bring Lower Proterozoic rock to the surface. The MCT is folded around the nose of the Hazara antiform where it steepens to include a complete Lower Proterozoic to Mesozoic rock sequence in its hanging wall block. The Pakistan Himalaya west of the syntaxis, including the Swat area, forms the NW corner of exposed Indian continental crust. Metamorphism and major deformation are associated with two opposing thrust systems that occurred nearly synchronously prior to and possibly during the metamorphic peak. The earliest is associated with underthrusting beneath southwestward advancing ophiolitic mélange of the Indus suture zone consistent with early fold vergence and stretching lineations in Swat, and with kinematic indicators east of the syntaxis in Zanskar. This was followed by underthusting beneath southeastward advancing Nawagai ophiolitic mélange consistent with kinematic indicators in the West Pakistan fold belt. Both mélange units are metamorphosed with Indian plate

  5. Subsurface mapping in the Iberian Pyrite Belt using seismic reflection profiling and potential-field data

    Science.gov (United States)

    Carvalho, João; Inverno, Carlos; Matos, João Xavier; Rosa, Carlos; Granado, Isabel; Branch, Tim; Represas, Patrícia; Carabaneanu, Livia; Matias, Luís; Sousa, Pedro

    2017-04-01

    The Iberian Pyrite Belt (IPB) hosts world-class massive sulphide deposits, such as Neves-Corvo in Portugal and Rio Tinto in Spain. In Portugal, the Palaeozoic Volcanic-Sedimentary Complex (VSC) hosts these ore deposits, extending from the Grândola-Alcácer region to the Spanish border with a NW-SE to WNW-ESE trend. In the study area, between the Neves-Corvo mine region and Alcoutim (close to the Spanish border), the VSC outcrops only in a small horst near Alcoutim. Sparse exploration drill-hole data indicate that the depth to the top of the VSC varies from several 100 m to about 1 km beneath the Mértola Formation Flysch cover. Mapping of the VSC to the SE of Neves-Corvo mine is an important exploration goal and motivated the acquisition of six 2D seismic reflection profiles with a total length of approximately 82 km in order to map the hidden extension of the VSC. The data, providing information deeper than 10 km at some locations, were integrated in a 3D software environment along with potential-field, geological and drill-hole data to form a 3D structural framework model. Seismic data show strong reflections that represent several long Variscan thrust planes that smoothly dip to the NNE. Outcropping and previously unknown Late Variscan near-vertical faults were also mapped. Our data strongly suggest that the structural framework of Neves-Corvo extends south-eastwards to Alcoutim. Furthermore, the VSC top is located at depths that show the existence within the IPB of new areas with good potential to develop exploration projects envisaging the discovery of massive sulphide deposits of the Neves-Corvo type.

  6. GRAVIMETRIC STUDY OF THE IXTLAN DE LOS HERVORES, GEOTHERMAL AREA, MIDWESTERN MEXICAN VOLCANIC BELT (MVB)

    Science.gov (United States)

    Gonzalez, T.; Ortiz, I.

    2009-12-01

    Analysis and interpretation of gravimetric anomalies over the Occidental-Central Mexican Volcanic Belt, sheds new light on the subsurface structure of the Ixtlan de los Hervores, geothermal area. In Mexico, there are several geothermal areas that have been exploited commercially (Cerro Prieto, Los Azufres, Los Humeros, Tres Virgenes fields). However, there are many other known fields that have not been exploited. This is the case in the area of "Ixtlan de los Hervores" in the state of Michoacan. The analyzed region covers a rectangular area, aproximality from 20o N to 20.5° N and 102° W to 102.2°W. In the region there are thick basalt flows. The area is characterized by low and elongated hills formed by volcanic flows and on a smaller scale lacustrian sediments and major normal faults with a NW-SE direction particularly, the Ixtlan-Encinal fault which controls the trace of the Duero River and the Pajacuarán fault. The anomaly map was compared with the surface geology and the anomalies were correlated with major volcanic features, since our main interest was in mapping the subsurface faults and volcanic bodies. Two profiles were selected that cross major anomalies and the geothermal zone of Ixtlan. The Talwani algorithm for 2-D polygonal bodies has been used for calculating the theoretical anomalies. The proposed models adequately explain the main observed geological features. The models are made up of two lithostratigraphic units of volcanic rocks, represented by the Tertiary basalts, which adequately reflect the area's volcanic environment. These basaltic units, corresponding to different volcanic events were cut by the Ixtlan well. Both models reflect the existence of the Ixtlan-Encinal fault, the most important feature in the area which is also responsible for the existence of the geothermal area.

  7. Subsurface mapping in the Iberian Pyrite Belt using seismic reflection profiling and potential-field data

    Science.gov (United States)

    Carvalho, João; Inverno, Carlos; Matos, João Xavier; Rosa, Carlos; Granado, Isabel; Branch, Tim; Represas, Patrícia; Carabaneanu, Livia; Matias, Luís; Sousa, Pedro

    2016-06-01

    The Iberian Pyrite Belt (IPB) hosts world-class massive sulphide deposits, such as Neves-Corvo in Portugal and Rio Tinto in Spain. In Portugal, the Palaeozoic Volcanic-Sedimentary Complex (VSC) hosts these ore deposits, extending from the Grândola-Alcácer region to the Spanish border with a NW-SE to WNW-ESE trend. In the study area, between the Neves-Corvo mine region and Alcoutim (close to the Spanish border), the VSC outcrops only in a small horst near Alcoutim. Sparse exploration drill-hole data indicate that the depth to the top of the VSC varies from several 100 m to about 1 km beneath the Mértola Formation Flysch cover. Mapping of the VSC to the SE of Neves-Corvo mine is an important exploration goal and motivated the acquisition of six 2D seismic reflection profiles with a total length of approximately 82 km in order to map the hidden extension of the VSC. The data, providing information deeper than 10 km at some locations, were integrated in a 3D software environment along with potential-field, geological and drill-hole data to form a 3D structural framework model. Seismic data show strong reflections that represent several long Variscan thrust planes that smoothly dip to the NNE. Outcropping and previously unknown Late Variscan near-vertical faults were also mapped. Our data strongly suggest that the structural framework of Neves-Corvo extends south-eastwards to Alcoutim. Furthermore, the VSC top is located at depths that show the existence within the IPB of new areas with good potential to develop exploration projects envisaging the discovery of massive sulphide deposits of the Neves-Corvo type.

  8. Geometry and Kinematics of Tumuxiuke Fold and Thrust Belt in Bachu Uplift, Tarim Basin

    Science.gov (United States)

    Song, Z.; Tang, L.

    2016-12-01

    Bachu uplift, mainly characterized by a series of out-of-sequence basement involved structures, is a large scale Cenozoic structural unit located in the west of Tarim basin. The NW-SE oriented, arc shaped Tumuxiuke fold and thrust belt (TFTB), which is roughly 200km in length, constrains the northern boundary of Bachu uplift. Based on multiple 2D seismic reflection profiles, we analysed the differences in structural styles along the strike of TFTB. It is mainly consist of several basement involved thrust faults and associated folds (or monoclines). The western segment of TFTB is characterized by a single basement involved structure; as to the middle segment, there is also backthrust branching from the main basement involved structure; in contrast, the eastern segment is consist of basement involved contractional wedge structures. According to the analysis of stratigraphy involved in deformation, fault slip and growth strata, we summarized that the TFTB mainly constructed by the compressional stress during late Miocene Himalayan orogency. Then, we analyzed the kinematics of TFTB with trishear fault propagation folding model. It is suggested that the initial fault tip that located below the basement-cover contact began to propagate during the late Miocene epoch and the propagation to slip ratio (P/S) also changes along strike. At the early stage of compression, the P/S was low and sedimentary cover mainly folded; then, the thrust faults of western segment and middle segment propagated rapidly with high P/S ratio and broke through early formed folds into Neogene strata; but in the eastern segment, the main thrust fault pinch out in the thick gypsum salt layer of middle Cambrian and the sedimentary cover decoupled from basement. About the genesis of basement-involved structures of TFTB in the intracontinent circumstance, we consider the effect of positive inversion of late Proterozoic-early Palaeozoic rift which requires further evidences.

  9. Role of Neogene Exhumation and Sedimentation on Critical-Wedge Kinematics in the Zagros Orogenic Belt, Northeastern Iraq, Kurdistan

    Science.gov (United States)

    Koshnaw, R. I.; Horton, B. K.; Stockli, D. F.; Barber, D. E.; Tamar-Agha, M. Y.; Kendall, J. J.

    2014-12-01

    The Zagros orogenic belt and foreland basin formed during the Cenozoic Arabia-Eurasia collision, but the precise histories of shortening and sediment accumulation remain ambiguous, especially at the NW extent of the fold-thrust belt in Iraqi Kurdistan. This region is characterized by well-preserved successions of Cenozoic clastic foreland-basin fill and deformed Paleozoic-Mesozoic hinterland bedrock. The study area provides an excellent opportunity to investigate the linkage between orogenic wedge behavior and surface processes of erosion and deposition. The aim of this research is to test whether the Zagros orogenic wedge advanced steadily under critical to supercritical wedge conditions involving in-sequence thrusting with minimal erosion or propagated intermittently under subcritical condition involving out-of-sequence deformation with intense erosion. These endmember modes of mountain building can be assessed by integrating geo/thermochronologic and basin analyses techniques, including apatite (U-Th)/He thermochronology, detrital zircon U-Pb geochronology, stratigraphic synthesis, and seismic interpretations. Preliminary apatite (U-Th)/He data indicate activation of the Main Zagros Fault (MZF) at ~10 Ma with frontal thrusts initiating at ~8 Ma. However, thermochronometric results from the intervening Mountain Front Flexure (MFF), located between the MZF and the frontal thrusts, suggest rapid exhumation at ~6 Ma. These results suggest that the MFF, represented by the thrust-cored Qaradagh anticline, represents a major episode of out-of-sequence deformation. Detrital zircon U-Pb analyses from the Neogene foreland-basin deposits show continuous sediment derivation from sources to the NNE in Iraq and western Iran, suggesting that out-of-sequence thrusting did not significantly alter sedimentary provenance. Rather, intense hinterland erosion and recycling of older foreland-basin fill dominated sediment delivery to the basin. The irregular distribution of

  10. Seat Belts Pay Off. The Use of Economic Incentives and Public Education to Increase Seat Belt Use in a Community. Final Report.

    Science.gov (United States)

    Campbell, B. J.; And Others

    A six-month campaign to increase seat belt use in Chapel Hill and Carrboro, North Carolina centered around the idea of giving out economic incentives for seat belt wearing. The approach was to stop vehicles at random and give all belted vehicle occupants a small prize and a chance for a large cash prize. Precampaign activities involve collecting…

  11. Evaluation of legislation on seat belt use on rear seats : social persuasion as a new measure to promote seat belt use.

    NARCIS (Netherlands)

    Oei, H.-l.

    1996-01-01

    In the Netherlands, the use of seat belts for front seat passengers was made compulsory in 1975, and on April 1st 1992 the use of rear seat belts, if fitted, became a legal requirement. Since 1968, an annual survey of the presence and use of seat belts on front seats - extended in 1989 to include re

  12. Evaluation of legislation on seat belt use on rear seats : social persuasion as a new measure to promote seat belt use.

    NARCIS (Netherlands)

    Oei, H.-l.

    1996-01-01

    In the Netherlands, the use of seat belts for front seat passengers was made compulsory in 1975, and on April 1st 1992 the use of rear seat belts, if fitted, became a legal requirement. Since 1968, an annual survey of the presence and use of seat belts on front seats - extended in 1989 to include

  13. Meningococcal carriage in the African meningitis belt

    Science.gov (United States)

    2013-01-01

    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent the acquisition of pharyngeal carriage as well as invasive meningococcal disease and whether PsA-TT can prevent pharyngeal carriage needs to be determined. To address this issue, a consortium (the African Meningococcal Carriage (MenAfriCar) consortium) was established in 2009 to investigate the pattern of meningococcal carriage in countries of the African meningitis belt prior to and after the introduction of PsA-TT. This article describes how the consortium was established, its objectives and the standardised field and laboratory methods that were used to achieve these objectives. The experience of the MenAfriCar consortium will help in planning future studies on the epidemiology of meningococcal carriage in countries of the African meningitis belt and elsewhere. Un vaccin conjugué contenant un polysaccharide du sérogroupe A méningococcique et une anatoxine du tétanos (PsA-TT) (MenAfriVac™) est en cours de déploiement dans les pays de la ceinture africaine de la méningite. L’ expérience avec d’ autres vaccins conjugués polysaccharide/protéine a montré qu’ une partie importante de leur succès a été leur capacité à empêcher l’ acquisition du portage pharyngé et donc à arrêter la transmission et à induire une immunité de group. Si PsA-TT doit d’ atteindre l’ objectif de prévenir les épidémies, il devrait être en mesure d’ empêcher l’ acquisition du portage pharyngé ainsi que la méningococcie invasive et le fait que PsA-TT puisse emp

  14. The relationship between the plasmapause and outer belt electrons

    Science.gov (United States)

    Goldstein, J.; Baker, D. N.; Blake, J. B.; De Pascuale, S.; Funsten, H. O.; Jaynes, A. N.; Jahn, J.-M.; Kletzing, C. A.; Kurth, W. S.; Li, W.; Reeves, G. D.; Spence, H. E.

    2016-09-01

    We quantify the spatial relationship between the plasmapause and outer belt electrons for a 5 day period, 15-20 January 2013, by comparing locations of relativistic electron flux peaks to the plasmapause. A peak-finding algorithm is applied to 1.8-7.7 MeV relativistic electron flux data. A plasmapause gradient finder is applied to wave-derived electron number densities >10 cm-3. We identify two outer belts. Outer belt 1 is a stable zone of >3 MeV electrons located 1-2 RE inside the plasmapause. Outer belt 2 is a dynamic zone of plasma density. Belt 1 decayed on hiss timescales prior to a disturbance on 17 January and suffered only a modest dropout, perhaps owing to shielding by the plasmasphere. Afterward, the partially depleted belt 1 continued to decay at the initial rate. Belt 2 was emptied out by strong disturbance-time losses but restored within 24 h. For global context we use a plasmapause test particle simulation and derive a new plasmaspheric index Fp, the fraction of a circular drift orbit inside the plasmapause. We find that the locally measured plasmapause is (for this event) a good proxy for the globally integrated opportunity for losses in cold plasma. Our analysis of the 15-20 January 2013 time interval confirms that high-energy electron storage rings can persist for weeks or even months if prolonged quiet conditions prevail. This case study must be followed up by more general study (not limited to a 5 day period).