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Progress in Natural Science:Materials International 2007年第2期17卷 177-186页

作者： QI Guowei, ZHANG Jinjiang , WANG Xinshe and GUO Lei ( Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education, china School of Earth and Space sciences, Peking University, {2. 100871, china institute of geology, chinese academy of geological sciences, beijing 1.0037, china) [a]Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education China [b]School of Earth and Space sciences Peking University Beijing China [c]chinese academy of {2. sciences Institute of Geology Beijing China

Three large-scale thrusts developed in the Daqingshan orogen, Inner Mongolia, with a northeast-east trending from Louhuashan to Suletu are described in this paper. These northwest-directed thrusts, together with the four tectonic belts (or tectonic sheets) separated by these faults, formed a typical thrusting system. The originally defined Hohhot metamorphic core complex may be a tectonic sheet, making the uppermost tectonic unit of the thrusting system and truncated by the Daqingshan detachment fault on top. The existing tectono-chronological studies showed that the thrusting of this region possibly happened at the same time as the extension along the top detachment fault. This presents that the contraction and extension in Daqingshan orogen were probably simultaneous. The structural pattern of the Daqingshan orogen can be correlated to the Himalayan orogen, and models for simultaneous thrusting and detachment in Himalaya may give a hint for explaining the development of the Daqingshan orogen.

关键词： Daqingshan thrust metamorphic core complex detachment fault contraction-extension transform Himalaya.

Experimental Study on the Mechanism for the Formation of Sn- bearing Granite in Northern Guangxi

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 169-182,228页

作者： Liang Xiangji, Qiao Li, Wang Fusheng and Yang Chonghui institute of geology,{2., beijing institute of geology Chinese Academy of Geological Sciences Beijing

Experimental results have proved that the Xuefengian Sn-bearing biotite granites were formed by remelting and recrystallization of the Proterozoic metamorphic rocks of the Sibao Group at 500× 105-2.00× 105 Pa and 750-570℃ and further testified that the F- and B-bear-ing aqueous solution played an important part in decreasing the formation temperature of the rocks. The results tally with the reality of the field geology. The authors have thus brought to light the mechanism for the formation of the Sn-bearing biotite granites and expounded the significance of their formation in the crust dynamics of South china.

关键词： experimental study Sn-bearing biotite granites formation mechanism northern Guangxi

Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science china Earth sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG Shuxian2. DU Andao2. GAO Yongfeng3 & HUANG Wei4 1. institute of Mineral Resources, chinese academy of geological sciences,{2., china 2. National Center of Geoanalysis, chinese academy of geological sciences,{2., china 3. Shijiazhuang College of Economy, Shijiazhuang 056000, china 4. Xizang Bureau of geology and Mineral Resources, Lhasa 850000, china chinese Acad Geol Sci Inst Mineral Resources Beijing 100037 Peoples R China chinese Acad Geol Sci Natl Ctr Geoanal Beijing 100037 Peoples R China Shijiazhuang Coll Econ Shijiazhuang 056000 Peoples R China Xizang Bur Geol & Mineral Resources Lhasa 850000 Peoples R China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.2.) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.2.) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 2.—2. Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

^(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,{2., 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 {2. 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. 12.-12. 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.

Thrust Propagation in the Aqqikkol Lake Area, the East Kunlun Mountains, Northwestern china

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Acta Geologica Sinica(English Edition) 2003年第4期77卷 468-478页

作者： CUI Junwen, CHEN Wen, LI Pengwu, ZHANG Xiaowei and LI Li institute of geology,{2., beijing 1.0037 institute of geology Chinese Academy of Geological Sciences Beijing 100037

The western segment of the East Kunlun Mountains is one of the poorly studied regions in northwestern china. Through a structural analysis of the typical sections, we have the following views: (1) There is a very well developed fault system in the western segment of the East Kunlun Mountains and thrust propagation, normal slip and decoupling are the chief deformation events in this area. (2. Although the thrusting started in the Late Carboniferous and Late Triassic-Early Jurassic, strong activity took place in the Miocene-Quaternary when the Kumkol basin was strongly downwarped. (3) The tectonic pattern of coexistence of N-directed thrust propagation and S-directed normal slip in this area is consistent with the general tectonic pattern of the northern Qinghai-Tibet plateau and also very similar to that of the Himalayan region on the southern margin of the Qinghai-Tibet plateau, but their directions between the thrust propagation are opposite and all the strong thrust propagations occurred from the Miocene-Pliocene to Quaternary, a period featuring strong collision between the Indian plate and the Eurasian plate and abrupt uplift of the Qinghai-Tibet plateau. This oppositely directed thrust propagation and normal slip reveal such kinematic characteristics as symmetric propagations of deep-seated materials towards the north and south beneath the Qinghai-Tibet plateau and gravitational sliding of superficial materials towards the interior of the plateau. Therefore, the establishment of the fault system in the study area may provide an approach to the study of deep processes of the northern Qinghai-Tibet plateau and the construction of a unified geodynamic model for the uplift of the Qinghai-Tibet plateau.

关键词： western segment of the East Kunlun Mountains thrust propagation normal slip plate collision dynamic model

MELT AND FLUID INCLUSIONS IN IGNEOUS ROCKS IN CENTRAL XIZANG (TIBET)

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Science in china,Ser.B 1986年第7期29卷 771-784页

作者：王碧香 institute of geology chinese academy of {2. sciences beijing

Through a study of the characteristics and composition of melt and fluid inclusions in volcanic rocks and their associated granites in the subduction zone of the Tibetan plate, it has been found that the characteristics of the inclusions in quite a few minerals of various rock types are closely related to the nature of molten magmas, thickness of strata and cooling speed. Therefore, their characteristics may be used to discriminate different lithofacies types. In this paper the evolution and crystallization of magmas are discussed on the basis of the glass composition of the inclusions measured using the electron probe, and the gas composition and its parameters are used in elucidating the physico-chemical conditions of rock and ore formation.

关键词： TIBET MELT AND FLUID INCLUSIONS IN IGNEOUS ROCKS IN CENTRAL XIZANG

CARBONATITES FROM THE EASTERN HIMALAYAN SYNTAXIS: PETROLOGY AND TECTONIC IMPLICATIONS

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地学前缘 2000年第S1期7卷 10-11页

作者： Liu Yan 1, Zhong Dalai 2. Ji Jianqing 3(1 institute of geology,{2., beijing 1.0037, china 2.institute of geology & Geophysics, chinese academy of sciences, beijing 10002., china 3 Department of geology, Pek

Most carbonatites occur in relatively stable, intra\|plate areas but some are found to occur in near to plate margins and may be linked with plate separation (Woolley, 1989). Although many carbonatites have been discovered to occur in the orogenic belts in recent years, most of these rocks are related to post\|orogenic magmatism, that is, the rocks occur in the specially extensional setting. Therefore it is unusual that such magmatic rocks occur in the typical convergent environment. Here we report carbonatites and associated ultramafic and mafic rocks in the core of the eastern Himalayan syntaxis. The eastern Himalayan syntaxis consists of three tectonic units: the Gangdise, the Yarlung Zangbo, and the Himalayan units, each of which is bounded by faults (Liu & Zhong, 1997). The Himalayan unit, the northernmost exposed part of the Indian plate, is divided into two complexes, the amphibolite facies complex in the south and the granulite facies complex in the north. The granulite facies complex in the Himalayan unit have been argued to experience high\|pressure metamorphism and represent materials buried to upper\|mantle depths (Liu & Zhong, 1997). The carbonatites and associated ultramafic and mafic rocks only occur in the granulite facies rocks and are divided into two belts: northern and southern *** northern belt extends at least 30km, and is about 2.km in width. The southern belt extends several kilometers, and is 3km or so in width. Each belt consists mainly of differently compositional dykes, extending parallel to gneissosity of granulite facies gneiss. Carbonatitic agglomerates are observed in the northern belt. From the center of carbonatite dykes to country rocks, five types of rock are observed: the center parts of carbonatites, the rim parts of carbonatites, ultramafic and mafic rocks, altered rocks and country rocks. The gneissosity of country rock was deformed by intrusion of dykes.

关键词： Eastern Himalayan Syntaxis carbonatites ultramafic rocks carbonatitie magmatism convergent environment

Mass Extinction——A Fundamental Indicator for Major Natural Divisions of geological History

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Acta Geologica Sinica(English Edition) 1988年第1期1卷 1-12页

作者： Xu Daoyi Zhang Qinwen Sun Yiyin institute of geology, State Seismological Bureau, {2. institute of geology, chinese academy of geological sciences, {2. institute of geology, Academia Sinica, {2. institute of geology State Seismological Bureau Beijing China

In the Phanerozoic, there are three major geological boundaries: Precambrian/***/Triassic and Cretaceous/Tertiary. Studies of these boundaries in china and over the world stronglysuggest that they have the following similar features: mass extinctions of many taxa, positive anomalies ofplatinum-group metals, and abrupt changes of stable isotopes (δ13C). It is quite probable that these were theconsequences of some rare catastrophic events of extraterrestrial origin. Hence, the three above-mentionedmass extinction events may be regarded as key indicators for the division of the geological history of thePhanerozoic.

关键词： Mass Extinction A Fundamental Indicator for Major Natural Divisions of geological History

Searching for the remains of subducted continental slabs

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chinese Science Bulletin 2000年第5期45卷 385-386页

作者： LIU Guangdinginstitute of geology and Geophysics, {2. academy of sciences, beijing 100101, china institute of geology and Geophysics Chinese Academy of Sciences Beijing China

On the basis of oceanic geological and geophysical observations the global plate tectonics theory wasput forward in the late 1960s. It inherited the essence of mobilism of continental drift and sea-floorspreading, caused a revolution of earth sciences in the twentieth century. But plate tectonics cannotsatisfactorily explain the complicated geological phenomena of continents, it fails in elucidating

关键词： Searching for the remains of subducted continental slabs der Nature

Discovery of Cu-Zn,Cu-Sn intermetallic minerals and its significance for genesis of the Mianning-Dechang REE Metallogenic Belt,Sichuan Province,china

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Science china Earth sciences 2006年第6期49卷 597-603页

作者： XIE Yuling1, HOU Zengqian2. XU Jiuhua1, YUAN Zhongxin2. BAI Ge2.& LI Xiaoyu3 1. Civil and Environmental Engineering School, University of Science and Technology beijing, beijing 100083,{2. 2. institute of geology, chinese academy of geological sciences, beijing 1.0037,{2. 3. The 109th geological Team, Sichuan Bureau of Mineral Exploration, Chengdu 610100,{2. 1. Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China 2. institute of geology Chinese Academy of Geological Sciences Beijing 100037 China 3. The 109th geological Team Sichuan Bureau of Mineral Exploration Chengdu 610100 China

Mianning-Dechang Himalayan REE Metallogenetic Belt in Sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2.n), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

关键词： Mianning-Dechang REE metallogenetic belt, Cu-bearing intermetallic minerals, EPMA, genesis significance, deep source magmatic activity.