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Have a correct understanding of the attribute of geologic environmentgive full play to the role of geoscience in environmental protection

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Journal of Environmental Sciences 1995年第4期7卷 491-501页

作者： Ha Chengyou(institute of Environmental geology, Ministry of geology and mineral resources, beijing 100081 , china)

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ＨａｖｅａｃｏｒｒｅｃｔｕｎｄｅｒｓｔａｎｄｉｎｇｏｆｔｈｅａｔｔｒｉｂｕｔｅｏｆｇｅｏｌｏｇｉｃｅｎｖｉｒｏｎｍｅｎｔｇｉｖｅｆｕｌｌｐｌａｙｔｏｔｈｅｒｏｌｅｏｆｇｅｏｓｃｉｅｎｃｅｉｎｅｎｖｉｒｏｎｍｅｎｔａｌｐｒｏｔｅｃｔｉｏｎＨａＣｈｅｎｇ...

关键词： geologic environment attribute geologic resources geologic capacity geologic disaster.

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.

^(40)Ar-^(39)Ar dating and geological implication of auriferous altered rocks from the middle-deep section of Q875 gold-quartz vein in Xiaoqinling area, Henan,china

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Chinese Science Bulletin 2002年第20期47卷 1750-1755页

作者： WANG Yitian, MAO Jingwen, LU Xinxiang & YE Anwanginstitute of mineral resources, Chinese Academy of Geological Sciences, beijing 100037, china institute of Geological Sciences, Henan Province, Zhengzhou 450053, china Lingbao bureau of geology and mineral institute of mineral resources Chinese Acad. of Geological Sciences Beijing 100037 China institute of Geological Sciences Henan Province Zhengzhou 450053 China Lingbao Bur. of Geol./mineral Rsrc. Henan Province Lingbao 472500 China

The 40Ar-39Ar age method is employed in this work to analyze the auriferous altered rocks from the middle-deep section of the Q875 gold-quartz vein in the Xiao-qinling area, and the results show that the main gold deposition of the Q875 occurred in ca. 128-126 Ma. As a typical gold-bearing quartz vein in this gold-rich area, the age data obtained from the Q875 also constrain on the metallogenic time of the lode gold deposits developed in the same geological settings. This geochronological study supplies new evidence for further understanding the timing of gold mineralization, the genesis of gold deposits and the geodynamic settings in Xiaoqinling area.

关键词： 40Ar-39Ar dating auriferous altered rock Q875 gold-quartz vein lode gold deposit metallogenic time Xiaoqinling.

Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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Science china Earth Sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. Key Laboratory of mineral resources, institute of geology and Geophysics, Chinese Academy of Sciences, beijing 10002., china 2. beijing institute of geology for mineral resources, beijing 100012, china Correspondence should be addressed to Wang Lijuan (email: wlj@***) Key Laboratory of mineral resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China beijing institute of geology for mineral resources Beijing China

Fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North china Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

Sulfide-melt inclusions in mantle xenoliths of Hannuoba,china

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Chinese Science Bulletin 1999年第2期44卷 166-170页

作者： XU Jiuhua , CHU Xuelei , ZHOU Yiming , DU YuanfuUniversity of Science and Technology beijing, beijing 100083, china china University of Geosciences( beijing) , beijing 100083, china The research Center of mineral resources Exploration , beijing 100101, china institute of geology, Chinese Academy of Sciences, beijing 10002., china University of Science and Technology beijing Beijing China china University of Geosciences (beijing) Beijing China The research Center of mineral resources Exploration Beijing China institute of geology Chinese Academy of Sciences Beijing China

Sulfide fluid incluision study on mantle xenoliths of Hannouba has been carried out by EPMA analysis. It is indicated that the Ni/Fe ratios of metal sulfides in sulfide-melt inclusions from Hannuoba seem to be related to host rocks. These data of lherzolite （pentlandite） are obviously higher than those of olivine pyroxenite （mainly pentlandite, partly pyrrhotine）. The LRM analysis shows that sulfur （H2S+SO2） occupies larger proportion in gas composition of CO2 fluid inclusions, generally more than mol 20 %. This may be related to sulfide inclusions which are frequently found.

关键词： mantle xenolith sulfide-melt inclusion EPMA.

Magnetic Fabric of Cuizhao Pluton and ItsEmplacement Significance

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Journal of Earth Science 1999年第3期18卷 274-279页

作者： Zhou Weixin(institute of geology, china Seismological bureau, beijing 10002.)Wan Tianfeng(Department of geology and mineral resources, china University of Geosciences, beijing 100083) institute of geology China Seismological Bureau Beijing 100029 Department of geology and mineral resources China University of Geosciences Beijing 100083

The new micro-structural and magnetic fabric data on Cuizhao plutou and their emplacement implications are demonstrated in this peper. The magnetic foliations develop better and the degree of magnetic susceptibility anlsotropy is larger in the margin of the pluton than that in the center,which reveals mainly horizontal compression or magma during emplacement- The mapnetic lineations are not very well developed. The magnetic fabrics in the Cuizhao pluton reveal horizontal compression like the bollooning model during emplacement near the Earth surrace. This feature was fixed in later tectonic events.

关键词： granitoid pluton magnetic fabric foliation lineation emplacement mechanism

Types, Metallogenic Environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in china

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 79-92页

作者： Wang Zhitian and Qin Kezhang beijing institute of geology for mineral resources, CNNC, beijing Zhang Zhongmin beijing institute of geology for mineral resources CNNC Beijing

Based upon a comprehensive study of 123 copper deposits in china. this paper reaches the following conclusions: 1. The crust in china was solidified pretty late; with the accretion of the plate, the copper mineralization moved towards its margin in space and became successively younger in age. 2. The major copper ore types ever found in the world have mostly been discovered in china, in which the porphyry type seems to be the most important and the massive sulfide type in the transitional bed between marine clastic and carbonate rocks is clearly defined. 3. Carbonate strata are widespread in china and their deposition lasted for a long geological period, so the proportion of copper deposits occurring in them is large as compared with other parts of the world. 4. Seven metallogenic epochs can be recognized, in which the Mesozoic one plays the leading role and the middle(late) Palaeozoic and Cenozoic ones are next in importance. mineralization was comparatively simple in the early geological period. and became diversified later on. In the early epochs copper deposits related to basaltic magmatism and metamorphosed marine sediments predominated, whereas in the later epochs those related to granitic magmatism and continental sedimentation were dominant. 5. There exist in china thirteen metallogenic provinces, of which the Lower Yangtze downwarping belt, Sanjiang fold system, Jiangnan axis and Xikang-Yunnan axis are of greater significance. 6. The crustal mobility in china was rather pronounced, the polycyclic evolution of the crust has resulted in such obvious phenomena as the inheritance of mineralization, the coexistence of various types and the superposition of different genetic types.

关键词： Metallogenic Environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in china Types

A special intermediate-low temperature PGE-As-Co mineralization

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Chinese Science Bulletin 1999年第S2期44卷 42-44页

作者： WANG Jingbin, WANG Yuwang and WANG Lijuan beijing institute of geology for mineral resources, china National Nonferrous Metal Industry Corporation, beijing 100012 china research Center of mineral resources Exploration, Chinese Academy of Sciences, beijing 100101, china

THIS paper introduces a new type of platinum-group elements (PGE) mineralization formed under a special condition of intermediate to low temperature, i. e. Huanggang PGE-As-Co deposit related to cryptoex-plosive hornblendite, Inner Mongolia, of which the proven reserves of arsenic reached small size. 1 geology of mineral district Huanggang PGE-As-Co deposit, located at the margin of Huanggang Mesozoic volcanic basin in thesouthern part of Da Hinggan Range, was controlled by both Huanggang-Ganzhuermiao deep fracture andvolcanic apparatus. The volcanic apparatus in a protruding cupola land-form is about 0.25 km^2. It wasfilled with rhyolitic volcanic breccia, brecciated tuff, subvolcanic dacite porphyry and brecciated lava ofvolcanic neck facies. The host hornblendite, of which Rb-Sr isochron age (bulk rock) is (90.66 ±14.44) Ma, intruded into the apparatus in the form of irregular dike (figure 1).

关键词： intermediate-low temperature PGE-As-Co mineralization Inner Mongolia.

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 100037, china 2. Development and research Center, china Geological Survey, beijing 100037, china 3. china University of Geosciences, beijing 100083, china 4. china University of Geosciences, Wuhan 430074, china 5. Information Center of Ministry of Land and resources, beijing 100812, china 6. institute of geology, State Seismological bureau, beijing 10002., 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