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Science Bulletin 2005年第14期 103-108页

作者： YU Gang1, YANG Gang1, CHEN Jiangfeng1, QU Wenjun2, DU Andao2 & HE Wei3.1. Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of china, Hefei 23.026, china 2. National Research Center of Geoanalysis, Chinese Academy of Geo- logical Sciences, Beijing 10003., china {3., liaoning province, dashiqiao 115100, china

the Maoling gold deposit, one of the large gold deposits in eastern liaoning province, NE china, is an ar- senopyrite-disseminated gold deposit with a resource of ap- proximately 25 t Au and an average Au grade of 3.2 g/t. Six arsenopyrites closely related to Au mineralization of the Maoling gold deposit are dated by Re-Os technique and de- fine a Re-Os isochron with an age of 23.6±140 Ma, which suggests that the deposit was formed in the Paleoproterozoic era rather than in the Indosinian period as some early re- searchers suggested. High initial 187Os/188Os ratio of 1.3.±0.48 indicates a crustal derivation of the ore-forming material of the deposit, which may be derived from rocks of the Gaixian formation of the Liaohe Group. Furthermore, the result also implies that the age of the Gaixian Formation in the Maoling district is older than 23.6±140 Ma.

关键词： Re-Os dating arsenopyrite Maoling gold deposit age of mineralization east of liaoning province.

Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science china Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3. WANG Fei4, SUN Yangui5, WEI Xiangdong3.& XING Zuoyun6 1. Division of Granite Geology, china geological survey, Yichang 443.03. china 2. Information Center of Ministry of Land and Resources, Beijing 100812, china 3. geological survey of Henan province and Institute of geological Research of Henan province, Zhengzhou 450053. china 4. geological Institute, china Seismological Bureau, Beijing 100029, china 5. geological survey Institute of Qinghai province, Xining 81003., china 6. china University of Geosciences, Wuhan 43.074, china Division of Granite Geology China Geological Survey Yichang China Information Center of Ministry of Land and Resources Beijing China geological survey of Henan province and Institute of geological Research of Henan province Zhengzhou China geological Institute China Seismological Bureau Beijing China geological survey Institute of Qinghai province Xining China china University of Geosciences Wuhan China

the Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in china, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North china plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. the results show that the age of (1776±3.)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. the discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western china and the basement of the North china plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient china continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

On the siltation of the middle Yangtze River

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Science china Earth Sciences 2004年第5期47卷 463-480页

作者： YIN Hongfu1, CHEN Guojin2, LI Chang抋n1 & WEI Yuan3.1. School of Earth Sciences, china University of Geosciences, Wuhan 43.074, china 2. Hydrogeological Team, Hubei Bureau of Geology and Mineral Resources, Jingzhou 43.100, china 3. geological survey of Jiangxi province, Nanchang 3.0201, china School of Earth Sciences China University of Geosciences Wuhan 430074 China Hydrogeological Team Hubei Bureau of Geol./Mineral Rsrc. Jingzhou 434100 China geological survey of Jiangxi Prov. Nanchang 330201 China

About 5.2×108 t/a of silts from the upper reach of the Yangtze River are transported through Yichang into the middle Yangtze River. the middle Yangtze itself and its tributaries yield ca. 0.8×108 t silts annually. Of this total 6×108 t/a input of silts, ca. 1.2×108 t/a are deposited within the river artery and lakes, while ca 4.83.108 t/a are at first transported into the lower reach through Datong, and then either deposited along the river and the Yangtze Delta, or output into the sea. Along the middle Yangtze River silting generally exceeds scouring, but the spatial and temporal distributions of scour-and-fill, as well as its distribution in the river valley transections, are uneven. Along the Yichang-Chenglingji and Jiujiang-Datong Segments of the middle Yangtze, scouring exceeds or equals silting. Silting mainly occurs along the Luoshan-Wuhan-Huangshi Segments with Wuhan as the pivotal point, as well as in the Dongting and Poyang Lakes. Even in these silting-dominated areas, there are times and parts of segments that scouring prevails. As to the transections, generally the river channel of main stream is scouring-dominated, forming V-shaped sections to a depth of 203. m or more, whereas the floodplains and bar islands are silting-dominated, forming wide and relatively high flats, which are often artificially transformed into protected embankments. Because the Jingjiang Levee separates the Jianghan Plain from Yangtze to the south, little has been deposited in that plain except a few sediments from the Han River—a tributary of the middle Yangtze. this factor plus the tectonic sag of that plain has made the altitude of plain surface several meters lower than that of the levee in most of the areas. Sil-tation along the Luoshan-Wuhan-Huangshi Segments has resulted in the elevation of flood level in this and upstream segments. River channel scouring plus floodplain silting have caused the transections of the middle Yangtze valley typically with deep channel and height

关键词： the middle Yangtze, scour-and-fill, siltation, silt utilization.

Medusoid Fossils from the Sinian Xingmincun Formation of Southern liaoning province

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 11-22,103-104页

作者： Hong Zuomin, Huang Zhenfu, Yang Xinde, Lan Jing, Xian Bingcai, Yang Yajun, Regional geological survey party, Bureau of Geology and Mineral Resources of{3., Jinzhou, liaoning and Liu Xiaoliang Shenyang Institute of Geology and Resources, Chinese Academy of geological Sciences, Shenyang, liaoning Fang Xinzhong 1Liang Yan Sun Tong Wang Fujun and Song Shao also took part in this work.

Abundant medusoid soft-bodied metazoan fossils have been found in the Sinian Xingmincun Formation(with an isotopic age of 650 Ma) at Qipanmo, Qidingshan and Yangtun of the Dalian-Jinzhou area, southern liaoning province; in addition, a number of macroscopic algal fossils have been discovered for the first time in the Getun Formation overlying the Xingmincun Formation. Medusoid fossils include 3.genera and 6 species(all of which are new). Judging from their biological characters, these medusoid fossils are considered to have an intimate affinity with the Ediacara fauna in the terminal Precambrian of Australia, as their characters are close to each other. the authors suggest that these medusoids and the Edicara fauna might be the products of the same period. the discovery of the medusoid fauna in the Xingmincun Formation marks an important event in the evolution of the terminal Precambrian organisms in china, and it is of major practical significance in the study of the Sinian System of china and the correlation of the Sinian strata of northern and southern china.

关键词： Medusoid Fossils from the Sinian Xingmincun Formation of Southern liaoning province

Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, china

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and LUO Xinrong (Postgraduate School of Guizhou University, Guiyang 550025, china Nanjing Institute of Geology and Mineral Resources, Nanjing 210016, china geological {3. of No. 3.geological party, Xinjiang, Kurle 841000, china) Postgraduate School of Guizhou University Guiyang 550025 China Nanjing Institute of Geology and Mineral Resources Nanjing 210016 China geological survey of No. 3.geological {3. Xinjiang Kurle 841000 China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3.1. 4 mm wide; their wrinkled lamellae are microfine with 3.10 pieces within the length of every each millimeter. the fossils are considered to be Sabellidites cambriensis Sokolov (1965) . the Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.

Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3. ZHOU Su3. LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3.1. Institute of Geology, Chinese Academy of geological Sciences, Beijing 10003., china 2. Development and Research Center, china geological survey, Beijing 10003., china 3. china University of Geosciences, Beijing 100083. china 4. china University of Geosciences, Wuhan 43.074, china 5. Information Center of Ministry of Land and Resources, Beijing 100812, china 6. Institute of Geology, State Seismological Bureau, Beijing 100029, china Institute of Geology Chinese Academy of Geological Sciences Beijing China Development and Research Center China Geological Survey Beijing China china University of Geosciences Beijing China china University of Geosciences Wuhan China Information Center of Ministry of Land and Resources Beijing China Institute of Geology State Seismological Bureau Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. the Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. the continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. the craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. the Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. the present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

Southeastern extension of the Red River fault zone (RRFZ) and its tectonic evolution significance in western South china Sea

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Science china Earth Sciences 2006年第8期49卷 839-850页

作者： LIU Baoming1,2,3. XIA Bin1, LI Xuxuan1,3. ZHANG Minqiang1,3. NIU Binhua2, ZHONG Lifeng1, JIN Qinghuan1,4 & JI Shaocheng1,5 1. Key Laboratory of Marginal Sea Geology and Resources, Chinese Academy of Sciences,Guangzhou 510640, china 2. china University of Geosciences (Beijing), Beijing 100083. china 3. Research Center of Science & Technology Department, CNOOC, Beijing 100027, china 4. Guangzhou Marine geological survey, Ministry of Land & Resources, Guangzhou 510075, china 5. Ecole Polytechnique Montreal, H3.3.7, Canada Key Laboratory of Marginal Sea Geology and Resources Chinese Academy of Sciences Guangzhou China china University of Geosciences (Beijing) Beijing China Research Center of Science & Technology Department CNOOC Beijing China Guangzhou Marine geological survey Ministry of Land & Resources Guangzhou China Ecole Polytechnique Montreal Canada

Recent geophysical surveys and basin modeling suggest that the No.1 fault in the Ying- gehai basin (YGHB) is the seaward elongation of the Red River fault zone (RRFZ) in the South china Sea (SCS). the RRFZ, which separates the South china and Indo{3. block, extends first along the Yuedong fault, offshore of Vietnam, and then continues southward and breaks off into two branches: the Lupar fault and the Tinjia fault. the southern extension of the Lupar fault dies out beneath the NW Borneo while the Tinjia fault extends southeast and reaches the Brunei-Sabah area. According to the gravity and geomagnetic data, and the tectonic evolution of the basins, there are different evolution histories between the Wan’an basin (WAB) and the basins in the Nansha block. the Tinjia fault may be the boundary between the Balingian block and the Nansha block. Hence, the line linking the Yue- dong fault and the Tinjia fault, which both are continental margin faults and strike-slip ones in the geological evolution histories, constitute the boundary between the Indo{3. and Nansha block. the Lupar fault, in contrast, is an intraplate fault within the Indo{3. block. the results provide new hints for reconstructing the tectonic evolution history of the RRFZ and the opening of the SCS, and also a framework for hydrocarbon prospecting in the region.

关键词： Red River fault zone, tectonic evolution, fault, extension, western South china Sea.

A new species of Macrocnemus (Reptilia: Protorosauria) from the Middle Triassic of southwestern china and its palaeogeographical implication

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Science china Earth Sciences 2007年第11期50卷 1601-1605页

作者： LI Chun1, ZHAO LiJun2 & WANG LiTing3.1 Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, china 2 Zhejiang Museum of Nature History, Hangzhou 3.0012, china 3.geological {3. of Guizhou province, Guiyang 550005, china Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China Zhejiang Museum of Nature History Hangzhou China geological survey of Guizhou province Guiyang China

A new species of the terrestrial protorosaur Macrocnemus is briefly described and named Macrocne-mus fuyuanensis sp. nov. the specimen was found from the marine Triassic of Yunnan province, southwestern china. It differs from the type species M. bassanii in having the following characters: (1) 17 or 18 dorsal vertebrae; (2) relatively long humerus; and (3. femur longer than tibia. M. fuyuanensis is the only record of the genus outside Monte San Giorgio area and the first definite terrestrial reptile found from the marine Triassic of china. the age of the fossil-bearing Zhuganpo Member of the Falang Formation is believed to be the Ladinian based on associated vertebrate fauna. the existence of Mac-rocnemus in the limestone suggests the presence of a terrestrial ecosystem which probably originated from the Anisian and well developed in the Ladinian in this region. the island system along the north-coast of Tethyan during the Triassic was probably an important route for the exchanges of reptiles, especially the terrestrial reptiles between the west and east.

关键词： Protorosauria,Middle Triassic,Ladinian,Yunnan,terrestrial reptile

Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 2. Henan Institute of geological survey, Zhengzhou 450007, china 3. State Key Laboratory of geological Processes and Mineral Resources at china University of Geosciences, Wuhan 43.074, china 4. Faculty of Material Sciences and Chemical Engineering, china University of Geosciences, Wuhan 43.074, china Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Henan Institute of geological survey Zhengzhou China State Key Laboratory of geological Processes and Mineral Resources at china University of Geosciences Wuhan China Faculty of Material Sciences and Chemical Engineering China University of Geosciences Wuhan China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. the positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. the large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

Timing and geochemical characters of the Sanchazi magmatic arc in Mianlüe tectonic zone,South Qinling

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Science china Earth Sciences 2004年第4期47卷 317-328页

作者： LI Shuguang1, HOU Zhenhui1, YANG Yongcheng2, SUN Weidong1,1), ZHANG Guowei3. & LI Qiuli1 1. School of Earth and Space Sciences,University of Science and Technology of china ,Hefei 23.026,china 2. Regional geological {3. Team of Shaanxi province,Xianyang 712000, china 3. Department of Geology, Northwest University,Xi抋n 710069, china School of Earth and Space Sciences University of Science and Technology of China Hefei China Regional geological survey Team of Shaanxi province Xianyang China Max-Planck-Institut f. Chemie Mainz Germany Department of Geology Northwest University Xi’an China

the Sanchazi mafic-ultramafic complex in Mianlüe tectonic zone,South Qinling can be subdivided into two blocks,*** paleo-magmatic arc and Zhuangkegou paleo-oceanic crust fragment (ophiolite).the Sanchazi paleo-magmatic arc is mainly composed of ande-site,basaltic and basalt-andesitic gabbro(or diorite),andesitic dyke,plagiogranite and minor ul-tramafric rocks,which have typical geochemical features of island arc volcanic rocks,such as high field strength element(***,Ti)depletions and lower Cr,Ni *** Light rare earth element (LREE) and K enrichments of these rocks and zircon xenocrystals of 900 Ma from plagiogranite suggest that this magmatic arc was developed on the South active continental margin of the South Qinling *** U-Pb age of (3.0±61) Ma for zircons from plagiogranite in-dicates that the Mianlüe paleo-oceanic crust was probably subducted underneath the South Qinling micro-continent in *** is consistent with the formation time (3.9Ma) of the Huwan eclogite originating form oceanic subduction in Dabie Mountains,suggesting that the Mianlüe paleo-ocean probably extended eastward to the Dabie Mountains in *** high-Mg adakitic rocks in Sanchazi paleo-magmatic arc suggest thet the subducted oceanic crust was relatively young (5Ma) and hot.

关键词： Qinling orogen, magmatic arc, U-Pb zircon age, ophiolite complex.