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Chinese Science Bulletin 2003年第22期48卷 2500-2506页

作者： WAN Yusheng1,2. ZHANG Qiaoda1 & SONG Tianrui1 1. institute of Geology, Chinese Academy of geological Sciences, Beijing 100037, China 2. Beijing SHRIMP Laboratory, Beijing 100037, China Correspondence should be addressed to Wan Yusheng (e-mail: wanyusheng@***) institute of Geology Chinese Academy of Geological Sciences Beijing China Beijing SHRIMP Laboratory Beijing China

The Mesoproterozoic Changcheng System is widely distributed in the North China Craton. Determining its time of deposition and sources is important to understand the Precambrian crustal evolution of the North China Craton. This paper suggests age distribution patterns for detrital zircons from clastic sediments of the Changcheng System in the Ming Tombs area, Beijing. Samples of feldspar-bearing sandstone (CHc-2. and pure sandstone (CHc-9) were collected from the Changzhougou Formation, which constitutes the basal part of the Changcheng System. Detrital zircons show an age range from 2.35 to 2.60 Ga. However, sample CHc-9 in the upper Changzhougou Formation also contains some zircons with ages of 1.9-1.8 Ga and 2.3-2.1 Ga. The age patterns lead to the following conclusions: (1) Most of the detrital material came from a source area composed predominantly of ~2.5 Ga continental crust of the North China Craton; (2. 1.9-1.8 Ga reflects the age record of Palaeoproterozoic continent-continent collisional event in the North China Craton; and (3) the oldest age for deposition of the Changcheng System is 1.8 Ga.

关键词：锆石原岩中国北部地区地壳演变

geological analysis and physical modeling of structural pumping in high effective formation of Kela 2.gas field

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Science China Earth Sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, WANG Hongjun1, SHAN Jiazeng2. WANG Zecheng1 & XU Dafeng1 1. Research institute of Petroleum Exploration and Development, Petrochina, Beijing 100083, China 2. institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China Research institute of Petroleum Exploration and Development Petrochina Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2.gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

The geological feature, geochemistry and origin of Jinya gold deposit in Fengshan, Guangxi

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Chinese Science Bulletin 1999年第S2期44卷 168-169页

作者： ZHOU Jiyuan~1, CUI Bingfang~1 and LU Yan~2.1. Nanjing institute of Geology and Mineral Resources, Nanjing 2.0016, China 2. Chengdu institute of Technology, Chengdu 610059, China Nanjing institute of Geology and Mineral Resources Nanjing 210016 China Chengdu institute of Technology Chengdu 610059 China

1 geological feature of deposit The Jinya gold deposit is a fine disseminated gold mine. It occurs in sandstone and mudstone ofMiddle-Triassic Baifeng Formation, which is located at the margin of Late Paleozoic carbonate platform. Itwas controlled by the fracture zone, cleavage zone and fissure zone. The gold deposit has 15 orebodies,which are displayed as beds, lens and veins. The dominating minerals with gold are pyrite and arsenopyrite. The gold mainly occurs as submicroscopic intergranular gold. Low-to-moderate temperature (130-305℃) wall-rock alterations are mainly silicification, pyritization and arsenopyrite, also includes realgarization, carbonation (calcite, dolomite), sericitization and argillation (kaolinite, pyrophyllite). It wasformed after undergoing the sedimentary diagenetic period, hydrothermal mineralization epoch (2.3 Ma)and supergene mineralization.

关键词： geological feature Jinya gold deposit Fengshan.

The tectonic setting and geochemical characteristics of metamorphic basement in the southwest of the Yangtze Plate

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Chinese Science Bulletin 1999年第S2期44卷 266-268页

作者： ZHANG Hongxiang~1, LIU Congqiang~2. HUANG Zhilong~2.and XU Zhifang~1 1. institute of Geophysics, Chinese Academy of Sciences, Beijing 100101, China 2. institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. China institute of Geophysics Chinese Academy of Sciences Beijing 100101 China institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE Dahongshan Group (in short DG) and its basement Dibadu Formation (in short DF) in the southeastof the Yangtze Plate are one of the oldest geological units in the Yangtze Plate. It is established in thisnote by means of geochemistry that the system of trench-arc-basin was formed by the subducting at thesouthwestern boundary of the Yangtze Plate in Lower Proterozoic Subera. And the existence of enrichedmantle EMI is argued by the way of trace elements geochemistry. 1 Regional geological setting There is a unit of the typical two-layer structure platform in the southwest of the Yangtze Plate. Themetamorphic basement of this platform is made up of Suberathem Dahongshan Group and SuberathemKunyang Group. Above them, there have covered expansive continental deposits from Mesozoic. The primary rocks of DG are composed of deposited limestone, sandstone and basalts. The basalts represent

关键词： Dahongshan Group(DG) Dibadu Formation(DF) tectonic geochemistry.

Oxygen isotope as a tracer of REE fractionation in water-rock interaction

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Chinese Science Bulletin 1999年第S2期44卷 224-226页

作者： DENG Hailin~1, LI Chaoyang~1, ZHOU Yunman~2.and WANG Chongwu~2.1. Open Laboratory of Ore Deposit Geochemistry, institute of Geochemistry Chinese Academy of Sciences, Guiyang 550002. China 2. No.1 geological Party, Yunnan Bureau of Geology and Mineral Resources, Xundian 6552.5, China Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China No. 1 geological Party Yunnan Bureau of Geology and Mineral Resources Xundian 655205 China

STABLE oxygen isotope is not only an effective approach to tracing water-rock interactions, but also canprovide much information about ore-forming temperature and source and evolution of ore fluids in thestudy of hydrothermal deposits. The rare-earth elements (REE) can be used to trace the sources ofore-forming materials and can also, to some extent, indicate the physical and chemical properties of fluids in the geochemical processes. The combination of these two aspects of research can effectivelyprobe into the geochemical behavior and evolution of REE in the process of water-rock interaction duringhydrothermal ore deposition. On the other hand, the essence of REE as tracers in hydrothermal mineralization can be better understood. In this note the Lemachang independent Ag deposit in northeastern Yunnan is selected for a case study.

关键词： oxygen isotope tracer water-rock interaction REE fractionation.

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, China

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Science China Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2. Faculty of Earth Sciences and Mineral Resources, China University of Geosciences, Beijing 100083, China 3. Tianjin institute of Geology and Mineral Resources, Tianjin 300170, China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing China Tianjin institute of Geology and Mineral Resources Tianjin China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science China Earth Sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3, GUO Zhengtang2.1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 2. institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 3. institute of Geomechanics, Chinese Academy of geological Sciences, Beijing 100081, China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Earth Environment Chinese Academy of Sciences Xi’an China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 2.3.1 m sequence varies from 6 to 13 μm and the > 63 μm fraction representsonly 5.3% in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

Wave tectono-sedimentary processes in Tarim basin

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Science China Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1,2. ZHANG Yiwei1 & CHEN Shuping1 1. Key Laboratory for Hydrocarbon Accumulation, Ministry of Education, China University of Petroleum, Beijing 102.49, China 2. Exploration and Production Research institute, China Petroleum & Chemical Corporation, Beijing 100083, China Key Laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum Beijing China Exploration and Production Research institute China Petroleum & Chemical Corporation Beijing China

Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 2.0±Ma, 100±Ma and 30±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 2.0±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

Source of ore-forming materials in Laowangzhai gold deposit, Yunnan. Evidence from lead isotopic composition

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Chinese Science Bulletin 1999年第S2期44卷 248-250页

作者： LI Yuan~1, XIAO Huayun~2. HUANG Zhilong~2. HAN Runsheng~1 and LIU Congqiang~2.1. Kunming University of Science and Technology, Kunming 650093, China 2. institute of Geochemistry, Chinses Academy of Sciences, Guiyang 550002. China Kunming University of Science and Technology Kunming 650093 China institute of Geochemistry Chinses Academy of Sciences Guiyang 550002 China

THE Laowangzhai superlarge gold deposit was found in 1984. Although studies on regional structure, geology of deposits and lamprophyres, which are temporally and spatially related to gold mineralization,have been carried out, the views on the source of ore-forming materials have been different. Thisnote summarized the characteristics of lead isotopic composition of the deposits, and probed further intothe source of ore-forming materials. 1 geological setting The Laowangzhai gold deposit, located in the north of the Ailaoshan fault zone, consists of Donggualin and Laowangzhai ore block. The strata in the orefield include Paleozoic （Pz3） epimetamorphic ma-

关键词： lead isotopic composition source of ore-forming materials Laowangzhai gold deposit.

The continental hydrothermal sedimentary origin of the Dashui superlarge gold deposit in Gansu Province, China

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Chinese Science Bulletin 1999年第S2期44卷 210-212页

作者： LI Hongyang~1, YANG Zhusen~1, GAO Zhenmin~1, LUO Taiyi~1, DING Zhenju~1 and YAN Shenghao~2.1. institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. China 2. institute of Mineral Deposits, Chinese Academy of {2. Sciences, Beijing 100037, China institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China

THE Dashui gold mine, situated in Gansu Province of western China, is a superlarge gold deposit newlydiscovered in western Qinling erogenic belt, hosted within the Permian-Triassic limestones and dolomites,as well as Jurassic conglomerates. It has been termed Carlin-type and hot spring-type gold ore, yet its origin is enigmatic. It is characterized by the formation of sedimentary and replacement bodies of hematite-hydrothermalsiliceous rocks above and adjacent to orebodies. The orebodies themselves exhibit a variety of geometries,such as funnels, pipes, sack-like, tabular zones parallel to bedding. NWW-EW striking, nearly SNstriking and NEE-NE striking faults control the ore-fluid passages. The orebody sites and shapes arelargely controlled by the intersection of such different strike faults. The ore mineral assemblage is characteristically gold-hematite-chalcedony. The gold mineralizationand hematitization and silification are closely interrelated. Five basic ore types are recognized: laminated-

关键词： continental hydrothermal sedimentation superlarge gold deposit Dashui Gansu.