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Science china Earth sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2 & SU Li3 1 Institute of geology, Chinese Academy of geological sciences, Beijing 100037, china 2 College of Earth sciences, Jilin university, Changchun 13.061, china 3.the geological laboratory center and state key laboratory of geological processes and mineral resources, china university of geo- sciences, Beijing 100083. china 1. Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China2. College of Earth Sciences Jilin University Changchun 130061 China3. The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.2.2.15 to 0.2.2.57, with εHf(t) values of 5.02.0.2., indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science china Earth sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2. WANG Qingfei1,2., HUANG Dinghua3 , WAN Li4, YANG Liqiang1,2.& GAO Bangfei1,2.1. state key {2. of geological processes and mineral resources, china university of geosciences, Beijing 100083. china 2. key {2. of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china university of geo- sciences, Beijing 100083. china 3. Faculty of Earth sciences, china university of geosciences, Wuhan 430074, china 4. School of Mathematics and Information Science, Guangzhou university, Guangzhou 510405, china 1. state key {2. of geological processes and mineral resources China University of Geosciences Beijing 100083 China 2. key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China 4. School of Mathematics and Information Science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and {2.logical facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of {2.logic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

Syndepositional Fault Controlling on Depositional Filling of the Third Member of Shahejie Formation in Beitang Sag

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Journal of Earth Science 2009年第6期20卷 949-958页

作者：黄传炎王华肖敦清陈思王家豪廖远涛 Faculty of Earth resources China University of Geosciences state key {2. of geological processes and mineral resources China University of Geosciences key laboratory of Tectonics and Petroleum {2. of Ministry of Education China University of GeosciencesWuhan Research Institute of Exploration and Development PetroChina Dagang Oilfield Company

In the continental lake basin whose structures were extraordinarily active, tectonism is an important factor in controlling the sequence and the depositional filling of the basin. This article reports the assemble patterns of syndepositional fault in the third member of Shahejie （沙河街） Formation in Beitang （北塘） sag. The results show that the comb-shape fracture system and the fracture transformation zone were developed in Beitang sag. These assemble patterns obviously controlled the sand-body and spatial distribution of sedimentary system. However, the steep slope belt of fault terrace, the multistage slope belt and the low uplift gentle slope belt controlled the development of sequence styles. Analyses of the spatial-temporal relationship of the assemble pattern of syndepositional faults and the sedimentary system help predict the favorable exploration zone.

关键词： Beitang sag syndepositional fault structural slope break zone the third member of Shahejie Formation.

Clay Rocks around Permian-Triassic Boundary at Daxiakou Section in Hubei Province,china

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Journal of Earth Science 2009年第6期20卷 909-920页

作者：张素新袁鹏赵来时童金南杨浩于吉顺史玉芳 state key {2. of geological processes and mineral resources China University of Geosciences Faculty of Earth sciences China University of Geosciences state key {2. of geological processes and mineral resources China University of Geosciences

We studied the clay rocks around the Permian-Triassic boundary at the Daxiakou （大峡口） Section in Xingshan （兴山）, Hubei （湖北） Province, china. All clay rocks are predominated by illitemontmorillonite （I/M） mixed-layer minerals, and high-temperature hexagonal bipyramid （HB） quartz and pyrite are contained in different abundances. Clay microspheres are even found in some beds. The results show that volcanic activity was very frequent in this area or in the neighboring areas during the Permian-Triassic transition though the intensity of eruption and the position of the eruption {2. might have varied during the period. The frequent volcanic activity should be at least one of the leading events to cause the momentous turnover of biota and the ecosystem during the great Permian-Triassic transition.

关键词： volcanic activity Permian-Triassic boundary Daxiakou Section Hubei Province.

Inclination Deepening of Paleogene Red Beds in the Qiangtang Terrane,the Hinterland of the Qinghai-Tibet Plateau

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地学前缘 2009年第S1期16卷 94-95页

作者： Bo Ran,Zhifei Liu,Chengshan Wang,Xixi Zhao,Yalin Li 1.College of Earth sciences,Chengdu university of Technology,Chengdu 610059,china. 2.laboratory of Marine geology,Tongji university,Shanghai 200092,china 3.state key laboratory of geological processes and mineral {13.,Research center for Tibetan Plateau geology,china university of geosciences,Beijing 100083.china 4.Institute of Tectonics and Earth sciences Department,university of California,Santa Cruz,CA 95064,USA

In this research,one hundred and ten samples（ten sampling localities）were drilled by a portable petrol-driven drill in the Tongtianhe area along the highway where developes Yaxicuo Group,Oligocene. Complete demagnetization were finished in university of California,Santa Cruz（UCSC）.These remanence data were collected:Dg=334.2.Ig=52.3,α95=7.1,k=7.3（before structural correction）;Ds=2..2. Is=66.6,α95=7.3,k=7.0（after structural correction）.

关键词： inclination deepening red beds Yaxicuo Group remagnetization

Micro-and submicrostructural evidence for high-temperature brittle-ductile transition deformation of hornblende: Case study of high-grade mylonites from Diancangshan, western Yunnan

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Science china Earth sciences 2007年第10期50卷 1459-1470页

作者： CAO ShuYun, LIU JunLai? & HU Ling state key {2. of geological processes and mineral resources (GPMR), china university of geosciences, Beijing 100083. china key {2. of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china university of geo- sciences, Beijing 100083. china 1. state key {2. of geological processes and mineral resources (GPMR) China University of Geosciences Beijing 100083 China 2. key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China

OM (optical microscope)/TEM (transmission electron microscope) micro- and submicrostructural analysis of hornblende rocks sheared at high temperatures from the Diancangshan area, western Yunnan reveals evidence for deformation in the brittle-ductile transition of hornblende at middle crustal level (about 637℃ and 0.653 GPa) and mechanisms of deformation in the transitional regime are further discussed. Sheared hornblende rocks at middle crustal level have typical mylonitic microstructures, shown by coarse porphyroclasts and fine matrix grains. Different mineral phases in the rocks show distinct deformation characteristics. Hornblende and feldspar grains are intensely deformed with ob- vious grainsize reduction, but quartz grains are recrystallized dominantly by grain growth. Hornblende grains show typical brittle-ductile transition nature. Initial crystallographic orientations of porphyro- clasts have strong effects on the behavior of grains during deformation. There are mainly two types of porphyroclasts, type I "hard" porphyroclasts and type II "soft" porphyroclasts, with [001] perpendicular and parallel to external shear stresses respectively. "Hard" porphyroclasts generally occur as compe- tent grains that are rarely deformed or sometimes deformed by fracturing and dislocation tangling. "Soft" porphyroclasts are highly deformed primarily by dislocation tangling (as shown in the cores of the porphyroclasts), but twinning, dislocation glide and climb probably due to hydrolytic weakening also contribute to dynamic recrystallization of the porphyroclasts into fine grains in the matrix. The micro- and submicrostructures of the two types of porphyroclasts and fine-grained matrix provide powerful evidence for the behavior of brittle-ductile transition of hornblende grains. It is concluded that twinning nucleation is one of the most important processes that operate during dynamic recrystalliza- tion of hornblende crystals at the brittle-ductile transition. (100) [001] t

关键词： hornblende, brittle-ductile transition, micro-and submicrostructures, twinning nucleation recrystallization, Diancangshan

SHRIMP Zircon U-Pb Ages and geochemical Characteristics of the Neoproterozoic Granitoids in the Huangling Anticline and Its Tectonic Setting

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Journal of Earth Science 2012年第5期23卷 659-675页

作者：魏运许彭松柏蒋幸福彭中勤彭练红李志宏周鹏曾雄伟 Wuhan Institute of geology and minerals {2. Wuhan Center of Geological Survey Faculty of Earth sciences China University of Geosciences Three Gorges Research center for geo-hazard Ministry of EducationChina University of Geosciences state key {2. of geological processes and mineral resources China University of Geosciences

SHRIMP zircon U-Pb dating of the Neoproterozoic Maoping （茅坪） series （Sandouping （三斗坪） rock suite） granites exposed in the southern part of the Huangling （黄陵） anticline shows that the formation time of Sandouping biotite-hornblende tonalite intrusion, Jinpansi （金盘寺） hornblende-biotite tonalite intrusion, and Longtanping （龙潭坪） monzogranite are 863±9, 842.10, and 844±10 Ma, respectively. Their geochemical features include A/CNK=0.98-1.06, from metaluminous to weakly peraluminous, δ=1.37-1.53, Sm/Nd=0.17-0.2., and RbN/YbN=1.1-3.62. These indicate that the granite rocks are supersaturated SiO2.calc-alkaline granitoids. The characteristic of Sr-Nd isotopic composition is that the values of εNd（t） and εsr（t） are -12.4 to -11.0 and 2..2.32.2. respectively. It also suggests that the material source of the granite rocks mainly originated from the crust, and they formed in a volcanic arc tectonic environment. These facts suggest that the occurrence of Neoproterozoic granitoids in the southern part of the Huangling anticline should be related to an arc environment along an active continental margin caused by southward subduction of oceanic crust beneath the northern Yangtze craton, and the formation age is not later than 863 Ma.

关键词： Huangling anticline Yangtze plate Neoproterozoic granitoid SHRIMP zircon U-Pbdating geochemistry tectonic setting.

Sr-Nd isotopic compositions of the Changjiang sediments: Implications for tracing sediment sources

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Science china Earth sciences 2007年第10期50卷 1556-1565页

作者： YANG ShouYe1?, JIANG ShaoYong2. LING HongFei2. XIA XiaoPing3, SUN Min3 & WANG DeJie4 1 state key {2. of Marine geology, Tongji university, Shanghai 2.0092. china 2.state key {2. for mineral Deposit Research, Nanjing university, Nanjing 2.0093, china 3 Departmen of Earth {12., The university of Hong Kong, Hong Kong SAR, china 4 Development Research center, china geological Survey, Beijing 100083. china 1. state key {2. of Marine geology Tongji University Shanghai 200092 China 2. state key {2. for mineral Deposit Research Nanjing University Nanjing 210093 China 3. Department of Earth sciences The University of Hong Kong Hong Kong SAR China 4. Development Research center China Geological Survey Beijing 100083 China

The suspended particulate and fine-grained floodplain sediments were collected from the main stream and tributaries of the Changjiang River for Sr-Nd isotopic measurements. The εNd(0) values gradually decrease downstream from -10.8 on average in the upper reaches to -12.3 in the lower reaches, whereas the 87Sr/86Sr ratios increase correspondingly, averaging 0.72.899 and 0.72.82. respectively in the upper and middle-lower reaches. The compositional variations primarily reflect the complex con- trols of provenance rocks, chemical weathering, and sediment characters between different catchments, among which the abnormal Sr-Nd isotopic compositions of the Yalong, Fujiang, Tuojiang and Yuanjiang rivers indicate the sediment provenance contributions from the Emeishan Basalt in the upper reaches and the old metamorphic and siliceous rocks in the middle-lower reaches. The Sr-Nd isotopic ratios of the Changjiang sediments can better reflect the average composition of weathered continental crust compared to other major rivers in the world because of the unique source rock types in the Changjiang drainage basin. The recognition of the Sr-Nd isotopic systematics of the Changjiang sediments will contribute to our understanding of the Changjiang evolution history and continental weathering processes during the Cenozoic, and also to reconstructing the paleoenvironmental changes in East china and the marginal seas.

关键词： Sr-Nd isotopes, sediment, Changjiang River, source rock, provenance

Relationship Between Organic Matters and Zn-Pb mineralization in the Giant Jinding Zn-Pb Deposit,SW china

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地学前缘 2009年第S1期16卷 163-163页

作者： Yongbao Gao,Chunji Xue,Jiangwei Zhang 1.Xi’an center,china {2.logical Survey,Xi’an 710054,china. 2.state key laboratory of {2.logical processes and mineral resources,Faculty of Earth sciences and resources, china university of {2.sciences(Beijing),Beijing 100083.china

The Jinding Zn-Pb deposit,Yunnan Province, southwestern china,represents the youngest,only continental sediment-hosted giant Zn-Pb deposit in the *** kinds of organic matters,such as the kerogen,light-and heavy-oil,hydrocarbon gas, bitumen of different occurrences and maturation,have been observed in recent underground and open pit ***-gas traces and oil-and methane-in-

关键词： organic matter former oil-gas reservoir hydrogen sulfide Jinding Zn-Pb deposit SW china

geochemistry and Petrogenesis of Preterozoic Basaltic Suites in Shennongjia Region,Yangtze Craton

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Geochemistry and Petrogenesis of Preterozoic Basaltic Suites...