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Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit,Southeastern Hubei Province

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矿物学报 2009年第S1期29卷 314-316页

作者： LI Jian-wei 1,2.DENG Xiao-dong1,2.ZHOU Mei-fu3.LIU Yong-sheng1(1. State Key Laboratory of geological Processes and Mineral Resources,China University of Geo{2.,Wuhan 43.074,China 2. Faculty of Earth Resources,China University of Geo{2.,Wuhan 43.074,China 3. Department of Earth {2.,the University of Hong Kong,Hong Kong)

Titanite(CaTi2.iO5) is an important accessory mineral not only in magmatic and metamorphic rocks,but also commonly in hydrothermal mineral deposits. It incorporates appreciable amounts(usually 10×10-6 s to 100×10-6 s) of U and Th into its structure and has a closure temperature of Pb diffusion higher than 660～700 ℃(Scott and St-Onge,1995) ,making it an ideal U-Th-Pb geochronometer. The Daye metallogenic district is located in the west of the giant Middle-Lower Yangtze River(MLYR) Cu-Fe-Au province,eastern China and is well endowed with Fe,Cu,and polymetallic skarn deposits.

关键词： Pb Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit,Southeastern Hubei Province Th Fe ICP Cu MS

Petrogenesis of Indosinian volcanic rocks in Songpan-Garze fold belt of the northeastern Tibetan Plateau:New evidence for lithospheric delamination

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Science China Earth sciences 2010年第9期53卷 1316-1328页

作者： CAI HongMing1,2. ZHANG HongFei1,2. XU WangChun1,2. SHI ZhangLiang1,2.& YUAN HongLin3.1 State Key Laboratory of geological Processes and Mineral Resources, Wuhan 43.074, China 2.Faculty of Earth sciences, China University of Geosciences, Wuhan 43.074, China 3.State Key Laboratory of Continental Dynamics, Northwest University, Xi’an 710069, China 1. State Key Laboratory of geological Processes and Mineral Resources Wuhan 430074 China2. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China3. State Key Laboratory of Continental Dynamics Northwest University Xi’an 710069 China

In the Songpan-Garze fold belt of the northeastern Tibetan Plateau, an Indosinian lithospheric delamination model has been proposed, based on previous investigation of widespread granitoids. However, this model lacks comparable information from volcanism in the area. During the Indosinian delamination in the Songpan-Garze fold belt, whether partial melting of litho- spheric mantle taken place is debated. This paper reports U-Pb zircon LA-ICP-MS ages, geochemical and Sr-Nd-Hf isotopic compositions from the Aba and Wasai calc-alkaline volcanic rocks in the central Songpan-Garze fold belt. Obtained magma crystallization ages are 2.0±3.Ma for the Aba andesite and 2.5±1 Ma for the Wasai andesite. These are consistent with magma crystallization ages of the late Indosinian granitoids in the Songpan-Garze fold belt that formed in a post-collisional tectonic setting. The Aba and Wasai andesites have distinct geochemical singnatures. The former has higher Al2.3. K2., Rb but lower Na2., Ba and Sr contents, suggesting differences in their magmatic evolution. The Aba andesites have ISr values of 0.7070-0.7076 and εNd(t) values of -3.9 to -5.3. and the Wasai andesites have ISr values of 0.7075-0.7077 and εNd(t) values of -3.6 to -3.9. Zircons show εHf(t) values of -3.7 to 0.3.for the Aba andesites and -2.7 to 5.5 for the Wasai andesites. Geochemical and Sr-Nd-Hf isotopic compositions indicate that fractional crystallization and crustal assimilation processes are not key roles for their magma evolution, implying that their chemical compositions are those of primary melts. We suggest that the magma of the Aba andesites originated predominantly from a crustal source, with a minor mantle-derived component. The source region of the magma was likely at the crust-mantle boundary. The magma of the Wasai andesites resulted from partial melting of lithospheric mantle, which was probably metasomatized by fluids so that it was amphibole bearing. The petrogenesis of the Aba and Wasai andesite

关键词： volcanism U-Pb dating geochemistry petrogenesis lithospheric delamination Songpan-Garze fold belt

Early J_2.basalts in SE China:Incipience of large-scale late Mesozoic magmatism

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Science China Earth sciences 2006年第8期49卷 796-815页

作者： XIE Xin1, XU Xisheng1, ZOU Haibo2. JIANG Shaoyong1, ZHANG Ming3.& QIU Jiansheng1 1. State Key Laboratory of Mineral Deposit Research, Department of Earth sciences, Nanjing University, Nanjing 2.0093. China 2. Department of Earth and Space sciences, University of California at Los Angeles, Los Angeles, CA90095-1567, USA. 3. GEMOC ARC National Key Centre, Department of Earth and Planetary sciences, Macquarie University, Sydney, N.S.W. 2.09, Australia 1. State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China 2. Department of Earth and Space sciences University of California at Los Angeles Los Angeles CA90095-1567 USA 3. GEMOC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney N.S.W. 2109 Australia

Magmatism in SE China was dormant during 2.4―180 Ma, but was reactivated in 180― 170 Ma (early J2., and then became more and more intensive towards the end of early Cretaceous. The small-scale early J2.magmatism is the incipience to long-term and large-scale magmatism in this region. A near east-west (EW) trend volcanic belt was distributed across south Hunan, south Jiangxi and southwest Fujian was formed during early J2.time. Along this belt from the inland toward the coast, the lithology of basalts changes from alkali into tholeiite, and the amount of erupted volcanic rocks and the proportions of rhyolites coexisting with the basalts increase. On the basis of geochemical char- acteristics of these basalts, we infer that the melting degree of source rocks and the extent of frac- tional crystallization and crustal contamination all increased whereas the depth of mantle source de- creased from the inland to the coast, which led to the variations of geological characteristics of the volcanic belt. In early J2. the western spreading Pacific plate began to subduct underneath SE China continental block, reactivating near EW trend deep fault that was originally formed during the Indos- inian event. The stress of the western spreading Pacific plate and the extent of asthenosphere up- welling increased from the inland to the coast, which is consistent with the generation and evolution of early J2.basalts.

关键词： early J2 basalts, upwelling of asthenosphere, large-scale magmatism, SE China, the Pacific plate.

Application of High-Resolution Sequence Stratigraphy to Precise Lacustrine Reservoir Correlations with an example from Linpan Oil Fleld,China

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沉积学报 1998年第2期 34-41页

作者： Jiang Zaixing1\ Cao Yingchang1\ Chang Lin1\ Ye Lianjun2.Li Renwei2.Zhou Xiangquan 3. Zhang Yong 3. Wang Ximing 3. Du Yumin 3.1(Dept.of Petroleum Resources sciences,Dongying,Shandong\ 2.7062. 2.geological Institute,Chinese Academy of Science

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关键词： Lake level change\ Sequence stratigraphy\ Reservoir Correlation

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science China Earth sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2. XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of geological Processes and Mineral Resources, China University of Geo{2., Wuhan 43.074, China 2. Institute of Resources & Environments, Henan Polytechnic University, Jiaozuo 454003. China 3. Department of Computer Science, South-Central University for Nationalities, Wuhan 43.074, China 4. Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. China Faculty of Earth Science and State Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Wuhan China Institute of Resources & Environments Henan Polytechnic University Jiaozuo China Department of Computer Science South-Central University for Nationalities Wuhan China Laboratory of Marine Geology Tongji University Shanghai China

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?2..3. (‰ V-PDB) to ?2..14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2.3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02. to 0.2.%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.2. to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South China, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2. climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South China.

The crystal structure of (Fe_(4)Cr_(4)Ni)_(9)C_(4)

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Science China Earth sciences 2005年第3期48卷 338-345页

作者： SHI Nicheng1, MA Zhesheng1, XIONG Ming1, DAI Mingquan1, BAI Wenji2. FANG Qingsong2. YAN Binggang2.& YANG Jingsui2.1. X-ray Diffraction Laboratory, China University of Geosciences, Beijing 100083. China 2. Institute of Geology, Chinese Academy of {2. sciences, Beijing 10003., China 1. X-ray Diffraction Laboratory China University of Geosciences 100083 Beijing China 2. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

(Fe4Cr4Ni)9C4 is a metal carbide mineral formed by combination of Fe, Cr and Ni with C. It occurs in a chromite deposit in the Luobusha ophiolite, Tibet. Based on the determina- tion of its crystal structure, the empirical formula is (Fe4.12.r3.84Ni0.96)8.92.3.70 and the simplified formula is (Fe4Cr4Ni)4C9. The mineral is hexagonal with a = 1.3.3.2.2. nm, c = 0.44690(9) nm, space group P63.m c, Z=6 and the calculated specific gravity Dx = 7.089 g/cm3. Fe, Cr and Ni occupy different crystallographic sites and their coordination numbers are approximately 12. forming an alternate stacking sequence of flat and puckered layers along the c axis. Some me- tallic atoms have a defect structure. The interatomic distances of Fe, Cr and Ni are 0.2.2.— 0.2.66 nm, and the distances between Fe, Cr, Ni and C are 0.1893.0.2.69 nm. The coordina- tion number of carbon is 6. It occurs in interstices of the metallic atoms Fe, Cr and Ni to form trigonal-prismatically coordinated polyhedra. These coordination polyhedra are linked with each other via shared corners or shared edges into a new type of metal carbide structure.

关键词： Luobusha of Tibet, metal carbide, crystal structure.

Mineralogy and Mode of Occurrence of Gold, Silver and Bismuth of the Caijiaying Lead-Zine-Silver Deposit, Hebei Province

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 371-385,461页

作者： Huang Dianhao Ding Xiaoshi Wu Chengyu Zhang Changjiang Institute of Mineral Deposits, Chinese Academy of geological sciences, Beijing geological Party No.3. Hebei Bureau of Geology and Mineral Resources, Zhang jiakou, Hebei Fei Zhenbi Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

The deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. These metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2.e. They are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold.

关键词： Mineralogy and Mode of Occurrence of Gold Hebei Province

Zircon SHRIMP U-Pb dating for the Cangshuipu volcanic rocks and its implications for the lower boundary age of the Nanhua strata in South China

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Science Bulletin 2003年第16期48卷 1663-1669页

作者： WANG Jian1, LI Xianhua2. DUAN Taizhong3. LIU Dunyi4, SONG Biao4, LI Zhongxiong1 & GAO Yonghua5 1. Chengdu Institute of Geology and Mineral Resources, China Geologi-cal Survey, Chengdu 610082. China 2. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, China 3. Colorado School of Mines, Golden, CO 80401-1887, USA (Present address: Marathon Oil Company, Houston, TX 77056-2.2., USA) 4. Institute of Geology, Chinese Academy of geological sciences, Bei-jing 10003., China 5. Graduate School of the Chinese Academy of geological sciences, Beijing 10003., China Correspondence should be addressed to Wang Jian (e-mail: jianwang@ ***) Chengdu Institute of Geology and Mineral Resources China Geological Survey Chengdu 610082 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Colorado School of Mines Golden CO 80401-1887 USA Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Graduate School of the Chinese Academy of geological sciences Beijing 100037 China

The continental volcanic rocks and volcaniclas-tic sedimentary conglomerates of the Cangshuipu Formation occur well in Yiyang of Hunan Province, consisting of a wedge-shaped succession of Neoproterozoic strata that over-lie with high-angle unconformity the flysch turbidites of the Lengjiaxi Group in the Upper Mesoproterozoic Eonothem. SHRIMP zircon U-Pb dating gives a weighted mean age of 814 12.Ma for the dacitic volcanic agglomerates from the lowest part of the volcanic rocks in the Cangshuipu Forma-tion. This age is younger than previously reported values of 92.—93. Ma for the volcanic rocks from the Cangshuipu Formation. Our new dating represents the lower boundary age of the Neoproterozoic System in the studied area. The younger age for the Cangshuipu volcanic rocks is supported by the following observations: （1） Lower Neoproterozoic strata （814—1000 Ma） are missing in the studied area; （2. the Nanhua rift system was initiated at about 82. Ma; and （3. an age of82. Ma may be taken as the lower boundary tim-ing of the Nanhua System （even Neoproterozoic） in South China.

关键词： Zicon U-Pb dating Neoproterozoic volcanics rift basin Nanhua System.

Research on the dynamics of the South China Sea opening:Evidence from analogue modeling

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Science China Earth sciences 2006年第10期49卷 1053-1069页

作者： SUN Zhen1,2. ZHOU Di1, ZHONG Zhihong3. XIA Bin2. QIU Xuelin1, ZENG Zuoxun4 & JIANG Jianqun5 1. CAS Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of sciences, Guangzhou 5103.1, China 2. CAS Key Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, China 3. Department of Technology, Shenzhen Branch of CNOOC, Guangzhou 5102.0, China 4. Faculty of Earth sciences, China University of Geosciences, Wuhan 43.074, China 5. Hainan Oil & Gas Exploration Company, Liaohe Oilfield PetroChina, Panjin 12.010, China 1. CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. CAS Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 3. Department of Technology Shenzhen Branch of CNOOC Guangzhou 510240 China 4. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China 5. Hainan Oil & Gas Exploration Company Liaohe Oilfield PetroChina Panjin 124010 China

Independent of Indochina extrusion, the South China Sea experienced a process from passive continental rifting to marginal sea drifting. According to the fault patterns in the Beibu Gulf basin and the Pearl River Mouth basin, the continental rifting and early spreading stage from 3. to 2. Ma were controlled by extensional stress field, which shifted clockwise from southeastward to south southeastward. From 2. Ma on, the sea spread in NW-SE direction and ceased spreading at around 15.5 Ma. Integrated geological information with the assumption that the South China Sea developed along a pre-Cenozoic weakness zone, we did analogue experiments on the South China Sea evolu- tion. Experiments revealed that the pre-existing weakness zone goes roughly along the uplift zone between the present Zhu-1 and Zhu-2.depression. The pre-existing weakness zone is composed of three segments trending NNE, roughly EW and NEE, respectively. The early opening of the South China Sea is accompanied with roughly 15° clockwise rotation, while the SE sub-sea basin opened with SE extension. Tinjar fault was the western boundary of the Nansha block (Dangerous Ground), while Lupar fault was the eastern boundary of the Indochina, NW-trending rift belt known as Zengmu basin developed between above two faults due to block divergent of Indochina from Nansha. In the experiment, transtensional flower structures along NW-trending faults are seen, and slight inversion occurs along some NE-dipping faults. The existence of rigid massifs changed the orientations of some faults and rift belt, and also led to deformation concentrate around the massifs. The rifting and drifting of the South China Sea might be caused by slab pull from the proto South China Sea subducting toward Borneo and/or mantle flow caused by India-Asia collision.

关键词： South China Sea, rifting and drifting, clockwise rotation, analogue modeling, rigid massifs.