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New geological evidence of crustal thickening in the Gangdese block prior to the Indo-Asian collision

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chinese Science Bulletin 2003年第15期48卷 1604-1610页

作者： DING Lin & LAI Qingzhou institute of geology and Geophysics, {2. academy of sciences, beijing 10002., china Correspondence should be addressed to Ding Lin (e-mail: dinglin@ ***) institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Recent mapping in the Gangdese block has revealed many leucogranites that are similar to those in the High Himalaya. These leucogranites formed at ~140 Ma as indicated by monazite Th-Pb ion-microprobe dating and cooled at ~130 Ma as indicated by muscovite 40Ar/39Ar dating. In conjunction with previous structural and paleogeographic studies, the new data indicate that the Gangdese block underwent crustal thickening and associated exhumation during ~140-130 Ma. In this regard, the southern margin of Eurasia continent was comparable to the modern South American Altiplano-Puna plateau, the prime example of active ocean-continent subduction and associated thickened crust. Specifically, the early stages of crustal thickening and uplifting of the Gangdese block may result from subduction of the Neo-Tethyan Ocean. If the Tibetan Plateau would form by accretion of a series of blocks with thickened crust, an elevated topographic plateau similar to the Altiplano- Puna plateau had formed before collision between the Indian and Eurasian plates. Then the Tibetan Plateau would have quickly thickened, uplifted, and begun to extend soon after onset of the collision. Thus, the deformational mechanism of the Tibetan Plateau is not distributed shortening, but rather concentrating deformation within regions of thin crust between the accreted blocks.

关键词：地质学地壳增厚亚洲淡色花岗岩喜马拉雅山脉

Types and Ore-forming Conditions of Gold Deposits in the Jinsha River-Lancang River-Nujiang River Area

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Acta Geologica Sinica(English Edition) 1993年第3期67卷 329-346页

作者： Yang Yueqing and Tian Nong institute of Mineral Deposits, chinese academy of geological sciences, {2. Zhang Zhongming

The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of china. Of a great variety of gold deposits present in this area, the following types seem to be economically most valuable and promising: tectonic alteration type in ophiolitic melange; polymetallic quartz vein type related to intermediate-acid intrusions; finely disseminated type in fracture zones; mixed hydrothermal type in tectonic fractures of carbonate rocks; hydrothermal type related to subvolcanic rocks; volcanic-hot spring type; submarine volcano exhalation-sedimentary-hydrothermal reformation type. Metallogenic epochs are exclusively Mesozoic and Cenozoic, and ore deposits and orebodies are controlled by linear structures. Magmatic activity has affected gold mineralization in varying degrees, and gold deposits are basically of mesothermal-epithermal type with ubiquitous and intense alterations. Ore-forming materials and hydrothermal solutions show multi-source character.

关键词： Jinsha River Lancang River Nujiang River gold deposit ophiolite hydrothermal alteration

Track Fading and Its Applications in Archaeology, Tectonics and Geothermal Chronology in china

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Journal of Earth Science 2013年第4期24卷 645-651页

作者：郭士伦袁万明陈宝流黄慰文刘顺生 Department of Nuclear Physics China Institute of Atomic Energy School of Earth sciences and Resourses China University of Geosciences Department of Radioisotopes China Institute of Atomic Energy institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Guangzhou institute of Geochemistry Chinese Academy of Sciences

Track fading is a basic phenomenon in track science and has been the source of informa- tion in geosciences. This article summarizes the knowledge of track fading and gives some examples of successful applications of track fading in archaeology, tectonics and geothermal chronology in china. The applications of track fading are classified into 5 modes：（1） mode of complete fading （annealing）; （2. mode of partial fading; （3） use of the dependence of track fading on time and temperature; （4） use of the differences of track fading between coexisting minerals; and （5） use of fading-reduced track length. Track fading mechanisms hints that scientists in geothermal chronology should adopt microprobes for quantitative elemental analysis to determine the detailed chemical compositions of each mineral grain or at least of the grains from each position of {2. structures in order that one becomes well aware of the relation between the track fading behavior and chemical compositions of the mineral used.

关键词： track fading archaeology tectonics geothermal chronology.

Analysis on the Dynamical Process of Donghekou Rockslide-Debris Flow Triggered by 5.12.Wenchuan Earthquake

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Journal of Mountain Science 2011年第2期8卷 140-148页

作者： SUN Ping ZHANG Yongshuang SHI Jusong CHEN Liwei Key Laboratory of Neotectonic Movement & Geohazard Ministry of Land and Resources Beijing China institute of Geomechanics Chinese Academy of Geological Sciences Beijing China china Nuclear Power Engineering Corporation Ltd. Beijing China

Among the geo-hazards caused by the great Wenchuan Earthquake, the rapid and long runout rockslide-debris flow is of primary concern due to the large volume of displaced material and the resultant catastrophic impacts to the landscape and socioeconomic structure. In order to analyze the dynamical process of this kind of geo-hazard, the Donghekou rockslide-debris flow is given as an example in this paper. This event, which killed 780 people, initiated at an elevation of 1300 m with a total long run-out distance of more than 2.00 m. The slide mass is mainly composed of dolomite limestone and siliceous limestone of Sinian system, together with carbon slate and phyllite of Cambrian. During the processes from slide initiation to the final cessation of slide movement, five dynamic stages took place, here identified as the initiation stage, the acceleration of movement stage, the air-blast effect stage, the impact and redirection stage and the long runout slidematerial accumulation stage. Field investigations indicate that due to the effects of the earthquake, the dynamics of the Donghekou rockslide-debris flow are apparently controlled by geologic and tectonic conditions, the local geomorphological aspects of the terrain, and the microstructural and macroscopic mechanical properties of rocks which compose the slide mass. These three main factors which dictate the Donghekou rockslide-debris flow dynamics are discussed in detail in this paper, and significant results of field investigations and tests of materials are presented. The above dynamical processes are analyzed in this paper, and some useful conclusions have been gained.

关键词： Dynamical process Donghekou Rockslide-debris flow Wenchuan earthquake

Features of inclusions in the Funiushan gold deposits of Central china and its implications for prospecting

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chinese Science Bulletin 1999年第S2期44卷 15-16页

作者： ZHANG Zhengwei~1, ZHU Bingquan~1 and DENG Jun~2.1. Guangzhou institute of Geochemistry, chinese {2. of sciences, Guangzhou 510640, china 2. china University of Geoscience, beijing 100083, china Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China china University of Geoscience Beijing 100083 China

GOLD mineralization popularly occurs in Funiushan area. Based on the studies on more than 40 gold deposits or ore spots, it is shown that most of them are small in scale except the Pengou gold deposit, whichcan be developed into a medium one. The Pengou is a gold deposit of medium-low temperature hydrothermal type. 1 geological setting The Funiushan gold mineralization zone lying in the contiguous region of Nanzhao, Fangcheng andLushan Counties, Henan Province, is stituated on the tectonic and geochemical boundary between theNorth china block and Qinling Orogenic belt, and transverses the two first-grade tectonic units. Thehost rocks are mainly the strata of Xionger group （Pt2./sub> ） and the Funiushan granitic batholith. The Penggougold deposit is just located on the large-scale fault of Xiatang-Guihe. A series of metamorphic rocks ofXionger Group outcroped in the north of the deposit. 2.The features of deposit The ore bodies mostly appear in thick plate with sag-and-swell variation. The gold-bearing alterationzone from upper to lower layers can be divided as granite→ pyritization and phyllic alteration→ alteredgranitic porphyry→quartz vein→pyritization and phyllic alteration→cataclastic granite with phyllic alteration, i. e. the upper and lower gold-bearing layers can be separated by the altered granite. The ore

关键词： gold deposit inclusion geochemistry Funiushan.

A new species of Leptocycas (Zamiaceae) from the Upper Triassic sediments of Liaoning Province,china

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Journal of Systematics and Evolution 2010年第4期48卷 286-301页

作者： 1,2.3Jian-Wei ZHANG 2.ian-Xin YAO 1Jia-Rui CHEN 1Cheng-Sen LI 1(State Key Laboratory of Systematic and Evolutionary Botany,institute of Botany,chinese {2. of sciences,beijing 100093,china) 2.State Key Laboratory of Stratigraphy and Paleontology,institute of geology,chinese {2. of geological sciences,beijing 10003.,china) 3(Graduate University,chinese {2. of sciences,beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (State Key Laboratory of Stratigraphy and Paleontology Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China) (Graduate University Chinese Academy of Sciences Beijing 100049 China) *Correspondence: Cheng-Sen LI *Correspondence: ?Author for correspondence. E-mail: lics@*** Tel.: 86-10-62.3-6436 Fax: 86-10-62.9-3385.

A new cycad,Leptocycas yangcaogouensis ***.,was found in sediments from the Late Triassic in western Liaoning,*** pinnately compound leaves(Pseudoctenis type)are screwed in a crown on the stem *** leaflets are linear,with parallel veins and decurrent bases on the *** leaf bases are *** cataphylls intermix with the *** female cone is ovoid in *** characteristics of the new plant are more similar to those of Leptocycas gracilis,a Triassic cycad from North America,but the new species differs from *** in the size of its stem(7–8 vs.3–5 cm in diameter,respectively),leaves(length×width 100×16 vs.30×7 cm,respectively)and leaf density along the stem(4–6 vs.1–2.bases/1 cm length,respectively).Both *** and ***,having leaves of the Pseudoctenis type,show a closer relationship to the extant Dioon of *** present study provides evidence for the origin of the genus Dioon,which may have come from Leptocycas plants of the *** would be assumed that the extent cycads in Zamiaceae originate from the pteridosperms in the Late Paleozoic and have evolved through the stage of *** and *** in Late Triassic,and reaching the extant Dioon.

关键词： china Cycadales Leptocycas Upper Triassic Zamiaceae

The Dabie Orogen as the early Jurassic sedimentary provenance: Constraints from the detrital zircon shrimp U-Pb dating

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Science china Earth sciences 2005年第2期48卷 145-155页

作者： LI Renwei, WAN Yusheng, CHENG Zhenyu, ZHOU Jianxiong, XU Yunhua, LI Zhong & JIANG Maosheng institute of geology and Geophysics, {2. academy of sciences, beijing 10002., china institute of geology, chinese academy of geological sciences, beijing 10003., china institute of Mineral Resources, chinese academy of geological sciences, beijing 10003., china 1. institute of geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of geology Chinese Academy of Geological Sciences 100037 Beijing China 3. institute of Mineral Resources Chinese Academy of Geological Sciences 100037 Beijing China

The shrimp U-Pb ages of detrital zircon from the oldest Mesozoic strata, the Fanghushan Fomation, in the Hefei Basin range from 2.0 Ma to ca. 2.00 Ma, which indicates that the Dabie Orogen as the early Jurassic sedimentary provenance was complex. The composition of the Dabie Orogen includes: the Triassic high pressure-ultrahigh pressure metamorphic rocks, of which the detrital zircon ages are from 2.4 Ma to 2.0 Ma; the rocks possibly related to the Qinling and Erlangping Groups representing the southern margin of the Sino-Korean craton in the Qinling and Dabie area, of which the detrital zircon has an age of 481-378 Ma; the Neoproterozoic rocks originated from the Yangtze croton, of which the detrital zircon ages are 799-72. Ma old; and the rocks with the detrital zircon ages of ca. 2.00 Ma and ca. 2.00 Ma, which could be the old basement of the Yangtze craton.

关键词： Hefei Basin, detrital zircon, shrimp U-Pb dating, Dabie Orogen.

Discovery of Enclaves from Cenozoic PuluVolcanic Rocks in West Kunlun Mountains and Itsgeological Implications

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Journal of china University of Geosciences 2002年第1期13卷 30-34页

作者： Zhang Zhaochong Xiao Xuchang Wang Jun Wang Yonginstitute of geology ,{2., beijing 10003. institute of geology Chinese Academy of Geological Sciences Beijing 100037

In this paper, we present the occurrence and mineral components of the enclaves firstly discovered in the Cenozoic Pulu volcanic rocks in west Kunlun Mountains, and propose that the enclave is accumulated by fractional crystallization within high-level magma chamber. In addition, the chemical compositions of its primary magma are calculated. The calculated compositions are similar to those of the Kangxiwa volcanic rocks that belong to the same volcanic belt in the Pulu volcanic region, suggesting their origin from the same source region. However, the temperatures and oxygen fugacity of magmas at high-level magma chamber decreased along with fractional crystallization.

关键词： enclave fractional crystallization volcanic rocks West Kunlun Mountains.

CENOZOIC COLLISIONAL DEFORMATION AND LITHOSPHERE TECTONIC EVOLUTION OF THE EASTERN HIMALAYAN SYNTAXIS

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地学前缘 2000年第S1期7卷 12-13页

作者： Ding Lin, Zhong Dalai, Zhang Jinjiang, Ji Jianqing(institute of geology and Geophysics, {2. academy of sciences, beijing 10002.,china)

The Eastern Himalayan Syntaxis (EHS) is one of the strongest deformation area along the Himalayan belt resulted from the collision between Indian plate and the Eurasian plate since 50～60Ma, and has sensitivity tracked and preserved the whole collisional processes. It should depend on the detail geological investigations to establish the deformational accommodate mode, and the uplift history, to elucidate the deep structure and the crust\|mantle interaction of the EHS. The Namjabarwa metamorphic complex indented into the Gangdise arc along the sinistral Pai shear fault and the dextral Aniqiao shear fault on the both sides of the Great Canyon of Yalung Zangbo river since the collision of the NE corner of the Indian plate and the Eurasian Plate at 60～70Ma [1] . The distance between Yarlung Zangbo suture and Bangong—Nujiang suture is shortened more 12.km in the EHS area than that of the Lhasa block.

关键词： Eastern Himalayan Syntaxis collisional deformation Magmatism and high\|pressure metamorphism Lithospheric evolution