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Chinese Journal Of Geochemistry 2004年第4期23卷 342-348页

作者：何明勤刘家军李朝阳李志明刘玉平杨爱平桑海清 Institute of Geochemistry Chinese Academy of Sciences China University of Geosciences Geological Party of Yunnan Bureau of geology and Mineral Resources Institute of geology and Geophysics Chinese Academy of Sciences

Ar- 39Ar fast neutron activation age spectrum of quartz in ore collected from the Baiyangping Cu-Co polymetallic ore-concentrated area, Lanping Basin, is saddle-shaped. The plateau age, minimum appearance age and isochron age shown on the spectra are 56.53± 0.43 Ma, 55.52± 1.78 Ma and 55.90± 0.29 Ma respectively. The age data are consistent with each other within 1σ uncertainties. Because the given initial 40Ar/ 36Ar value of 294.7± 1.14 is very close to Nier’s value ( 295.5±5), both plateau and isochron ages may be considered as the forming time of quartz. So the age of 55.90- 56.53 Ma represents the forming age of ore deposits. It is obvious that the ore deposits were formed during the Early himalayan period.

关键词：氩年龄测定喜玛拉雅早期运动铜-钴多金属矿集中地区云南西部

geology and Genesis of the Superlarge Jinchang Gold Deposit,NE China

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Acta Geologica Sinica(English Edition) 2008年第4期82卷 750-761页

作者： JIA Guozhi CHEN Jinrong YANG Zhaoguang BIAN Hongye WANG Yangzhong LIANG Haijun JIN Tonghe LI Zhenhui No. 1 Brigade Division of Gold People＇s Armed Police Force Harbin Heilongjiang 150086 Institute of Gold geology Division of Gold People＇s Armed Police Force Langfang Hebei 065000 No. 1 Team Division of Gold People＇s Armed Police Force Mudanjiang Heilongjiang 157000 No. 3 Team Division of Gold People＇s Armed Police Force Harbin Heilongjiang 150049

The superlarge Jinchang gold deposit is located in the joint area between the Taipingling uplift and the Laoheishan depression of the Xingkai Block in both eastern Jilin and eastern Heilongjiang Province. Wall rocks of the gold deposits are the Neoproterozoic Huangsong Group of metamorphic rocks. Yanshanian magmatism in this region can be divided into 5 phases, the diorite, the graphic granite, the granite, the granite porphyry and the diorite porphyrite, which resulted in the magmatic domes and cryptoexplosive breecia chimney followed by large-scale hydrothermal alteration. Gold mineralization is closely related to the fourth and fifth phase of magmatism. According to the occurrences, gold ores can be subdivided into auriferous pyritized quartz vein, auriferous quartz-pyrite vein, auriferous polymetailic sulfide quartz vein and auriferous pyritized calcite vein. The ages of the gold deposit are ranging from 122.53 to 119.40 Ma. The ore bodies were controlled by a uniform tectono-magmatic hydrothermal alteration system that the ore-forming materials were deep derived from and the ore-forming fluids were dominated by magmatic waters with addition of some atmospheric water in the later phase of mineralization. Gold mineralization took place in an environment of medium to high temperatures and medium pressures. Ore-forming fluids were the K^＋-Na^＋-Ca^2＋-Cl^--SO4^2- type and characterized by medium salinity or a slightly higher, weak alkaline and weak reductive. Au in the ore-forming fluids was transported as complexes of [Au （HS）2]^-, [AuCl2]^-, [Au（CO2）]^- and [Au（HCO3）2]^-. Along with the decline of temperatures and pressures, the ore-forming fluids varied from acidic to weak acidic and then to weak alkaline, which resulted in the dissociation of the complex and finally the precipitation of the gold.

关键词： magmatic dome cryptoexplosive breccia pipe ring and radial faults gold deposit,superlarge Jinchang Taipingling Heilongjiang

The Complex Phenomenon of Glaciers of Nubra Valley, Karakorum (Ladakh), India

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Natural Science 2014年第10期6卷 733-740页

作者： R. K. Ganjoo M. N. Koul I. M. Bahuguna Ajai Department of Geography University of Jammu Jammu India Institute of himalayan Glaciology c/o Department of Geology University of Jammu Jammu India Space Applications Centre Ahmedabad India

The Nubra valley nestled in the Karakorum Mountains of Ladakh houses about 600 glaciers of various dimensions out of which 114 glaciers were monitored in the first phase of study. The study of 114 glaciers suggests that small-sized glaciers outnumber the large-sized glaciers. Almost 52.6% of the studied glaciers are of the size less than 5 km and 31.5% of the total glaciers are between the size of 5 and 10 km. The 84 glaciers out of the 114 glaciers have been monitored on shortterm basis between the time period 1989 and 2001 whereas 30 glaciers have been monitored on long-term basis between 1969 and 2001. The monitoring of the glaciers is based on the study of Survey of India topographical sheets of 1969 and satellite imageries of time series between 1989 and 2001. The monitoring of thirty glaciers shows that 17 glaciers have lost their area between 1969 and 2001. The loss in area is from 2150 km2 in 1969 to 2026 km2 in 2001. The study of eighty- four glaciers on short-term basis between 1989 and 2001 suggests that 26 glaciers have retreated, 25 glaciers have advanced and 33 glaciers show no change during the time period. The changes in the glaciers of Nubra valley are varied and complex.

关键词： Nubra Valley Indus Basin Karakorum Himalaya Ladakh Siachen Glacier

Structural Characteristics and Formation Mechanism in the Micangshan Foreland,South China

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Acta Geologica Sinica(English Edition) 2009年第1期83卷 81-91页

作者： XU Huaming LIU Shu QU Guosheng LI Yanfeng SUN Gang LIU Kang Institute of geology China Earthquake Administration Beijing 100029 China Southwestern division Company ofSINOPEC Deyang Sichuan 618000 China National Earthquake Response Support Service China Earthquake Administration Beijing 100049 China

Lying at the junction of the Dabashan, Longmenshan and Qinling mountains, the Micangshan Orogenic Belt coupled with a basin is a duplex structure and back-thrust triangular belt with little horizontal displacement, small thrust faults and continuous sedimentary cover. On the basis of 3D seismic data, and through sedimentary and structural research, the Micangshan foreland can be divided into five subbelts, which from north to south are： basement thrust, frontal thrust, foreland depression-back-thrust triangle, foreland fold belt or anticline belt, and the Tongjiang Depression. Along the direction of strike from west to east, the arcuate structural belt of Micangshan can be divided into west, middle and east segments. During the collision between the Qinling and Yangtze plates, the Micangshan Orogenic Belt was subjected to the interaction of three rigid terranes： Bikou, Foping, and Fenghuangshan （a.k.a. Ziyang） terranes. The collision processes of rigid terranes controlled the structural development of the Micangshan foreland, which are：（a） the former collision between the Micangshan-Hannan and Bikou terranes forming the earlier rudiments of the structure; and （b） the later collision forming the main body of the structural belt. The formation processes of the Micangshan Orogenic Belt can be divided into four stages：（1） in the early stage of the Indosinian movement, the Micangshan-Hannan Rigid Terrane was jointed to the Qinling Plate by the clockwise subduction of the Yangtze Plate toward the Qinling Plate; （2） since the late Triassic, the earlier rudiments of the Tongnanba and Jiulongshan anticlines and corresponding syncline were formed by compression from different directions of the Bikou, Foping and Micangshan-Hannan terranes; （3） in the early stage of the himalayan movement, the Micangshan-Hannan Terrane formed the Micangshan Nappe torwards the foreland basin and the compression stresses were mainly concentrated along both its flanks, whereas the Micangshan-Han

关键词： arcuate structure Bikou duplex structure Foping Micangshan-Hannan orogenic belt,terrane Sichuan Yangtze Plate

Middle Pleistocene mammalian fauna of Shanyangzhai cave in Qinhuangdao area, China and its zoogeographical significance

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Chinese Science Bulletin 2010年第21期55卷 72-76页

作者： ZHANG YunXiang LI YongXiang WANG Wei GONG HuJun State Key Laboratory of Continental Dynamics Department of geology Northwest University Xi'an 710069 China

The mammalian fauna with clear characteristics of transitional region has been found in the Shanyangzhai cave of the Qin-huangdao area where the three Chinese zoogeographical regions (the Northeast region, the North region and the Mengxin region) join. Abundant fossils mainly are small mammals. The fauna includes typical species derived from three zoogeographical regions and can be compared with the middle Pleistocene faunas found in both the Zhoukoudian (the North region) and the Jinniushan (the Northeast region) faunas. Of 53 kinds of mammals identified at the site, 38 kinds can be seen on the list of the middle Pleis-tocene Zhoukoudian and the Jinniushan faunas, of which 29 kinds are the same as those in the Zhoukoudian fauna and 25 are in the Jinniushan fauna, 7 in the Salawusu fauna and account for 76%, 66% and 18% of the total, respectively. It is suggested based on the consistence of the constitution of the fauna and its recent zoogeographic division that the three regions in north China could be initially formed during the middle Pleistocene.

关键词：哺乳动物群秦皇岛地区中更新世中国洞穴地理学小型哺乳动物东北地区

Structural and tectonothermal evolution of the ultrahigh-temperature Bakhuis Granulite Belt,Guiana Shield,Surinam:Palaeoproterozoic to recent

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Geoscience Frontiers 2021年第2期12卷 677-692页

作者： Frank F.Beunk Emond W.F.de Roever Keewook Yi Fraukje M.Brouwer Faculty of Science Geology and Geochemistry ClusterVrije Universiteit Amsterdam(VUA)De Boelelaan 10851081HVAmsterdamthe Netherlands division of Earth and Environmental Sciences Korean Basic Science InstituteOchang363-833South Korea

We constrain the multistage tectonic evolution of the Palaeoproterozoic UHT metamorphic(P=0.9–1.0 GPa,T>1000℃,t=2088–2031 Ma)Bakhuis Granulite Belt(BGB)in Surinam on the Guiana Shield,using large-to small-scale structures,Al-in-hornblende thermobarometry and published fluid inclusion and zircon geochronological *** BGB forms a narrow,NE–SW striking belt between two formerly connected,~E–W oriented granite-greenstone belts,formed between converging Amazonian and West African continental masses prior to collision and Transamazonian *** detrital zircon in BGB metasediments conforms agewise to Birimian zircon of West Africa and suggests derivation from the subsequently subducted African passive ***-temperature metamorphism may have followed slab break-off and asthenospheric heat *** metamorphic structures result from layer-parallel shearing and folding,reflecting initial transtensional exhumation of the subducted African margin after slab break-off.A second HT event involves intrusion,at ca.0.49 GPa,of charnockites and metagabbros at 1993–1984 Ma and a layered anorthosite at 1980 Ma,after the BGB had already cooled to<400℃.The event is related to northward subduction under the greenstone belts,along a new active margin to their south.A pronounced syntaxial bend in the new margin points northward towards the BGB and is likely the result of indentation by an anticlinorial flexural bulge of the subducting *** of the subducting oceanic plate along this bulge explains why the charnockites are restricted to the *** BGB subsequently experienced doming under an extensional detachment exposed in its southwestern border *** was focused in the BGB as a result of the flexural bulge in the subducting plate and localised heating of the overriding plate by charnockite *** present,straight NE–SW long-side boundaries of the BGB are superimposed mylonite zones,overprinted by pseudotachylites,previously dated

关键词： Bakhuis granulite belt Guiana shield Transamazonian orogeny UHT metamorphism Tectonics P-T-t evolution

Microstructural and deformational studies on mylonite in the detachment faults of Yalashangbo dome, North himalayan domes zone

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Progress in Natural Science:Materials International 2005年第11期15卷 1005-1013页

作者： ZHANG Bo, ZHANG Jinjiang, GUO Lei and WANG Weiliang (Department of geology, School of Earth and Space Sciences, Peking University, Beijing 100871, China) Department of geology School of Earth and Space Sciences Peking University Beijing 100871 China

The Yalashangbo dome, located at the eastern end of North himalayan domes zone, has a geometry and structure similar to those of a metamorphic core complex. Ductile shear zones formed the detachment system around the dome and these zones are composed of garnet-bearing phyllonite, mylonitic schist, mylonitic gneiss and mylonitic granite. Ductile shear fabrics developed well in my-lonitic rocks, and penetrative lineation and foliation were formed by stretched quartz and feldspar and preferred orientation of mica. Polar Mohr diagram method is used to calculate the kinematic vorticity numbers of the shear zones in the detachment system. Results indicate that the shear zone is a thinned shear zone (thinning of 23 % ) in an extensional setting which underwent a general shear dominated by simple shear. Comparison of the vorticity numbers between the northern and southern flanks of the Yalashangbo dome shows that the dome is an asymmetric system formed by a north-northwest-directed detaching unanimously. Statistical fractal analysis shows that the shapes of dynamically recrystallized quartz grains in the mylonites have characteristics of self-similarity, with fractal numbers ranging from 1.05 to 1.18. From these fractal numbers, the strain rate of the rock was deduced from 10-9.2S-1 to 10-7.3S-1, the differential paleao-stress was 13.7-25.6 MPa during the deformation happened at a temperature over 500 ℃. The ductile shear zones in the detachment system around Yalashangbo dome were formed under a high green-schist grade condition or happened simultaneously with the intrusion of granite.

关键词： Yalashangbo dome ductile shear zone kinematic vorticity fractal analysis deformation temperature strain rate.

Partial melting of deeply subducted continental crust and the formation of quartzofeldspathic polyphase inclusions in the Sulu UHP eclogites

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Chinese Science Bulletin 2009年第15期54卷 2580-2594页

作者： ZENG LingSen LIANG FengHua ASIMOW Paul CHEN FangYuan CHEN JJng Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China division of Geological and Planetary Sciences California Institute of Technology Pasadena CA 91125 USA School of Physics Peking University Beijing 100871 China

Two types of quartzofeldspathic inclusions hosted by omphacite and garnet were identified in the Sulu UHP eclogites. The first consists of albite, quartz, and various amounts of K-feldspar. In contrast, the second consists predominantly of K-feldspar and quartz without any albite. The presence of quart-zofeldspathic inclusions within the UHP mafic eclogites indicates that partial melting occurred in deeply subducted continental crust via mica dehydration melting reactions at an early stage of rapid exhumation. Such a melting event generated hydrous Na-K-Al-Si melts. These melts infiltrated into the mafic eclogite and were captured by recrystallizing garnet or omphacite, which together followed by dehydration and crystallization to form feldspar-bearing polyphase inclusions. Formation of silicate melts within the deeply subducted continental slab not only provides an excellent medium to transport both mobile (LILE) and immobile (HFSE) elements over a large distance, but also induces effective changes in the physical properties of the UHP slab. This process could be a major factor that enhances rapid exhumation of a deeply subducted continental slab.

关键词：超高压榴辉岩大陆地壳深俯冲包裹体部分熔融多相体形快速折返

Magnetism in loess from Chuanxi Plateau （Eastern Tibetan Plateau）: the role of provenance and indications for pedogenesis

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Magnetism in loess from Chuanxi Plateau （Eastern Tibetan Pl...

“The response of stromatolites to seismic shocks: Tomboliths from the Palaeoproterozoic Chaibasa Formation,E India”: Reply

中国地球物理学会第二十九届年会

作者： Pengxiang Hu Qingsong Liu Chunsheng Jin division of Tethys Research Center Institute of Geology and Geophysics Chinese Academy of Sciences division of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences

＜正＞The Chuanxi Plateau locates at the eastern margin of the Tibetan Plateau, dominated by Indian Monsoon in the summer and the Westerly in winter, and thus is sensitive to climatic changes. This study investigated the soil magnetism through a loess-paleosol sequence since ～55 ka at the Ganzi section to determine the major factors controlling the magnetism and response of magnetic iron oxides to pedogenesis in different

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Journal of Palaeogeography 2017年第3期6卷 235-241页

作者： A.J. (Tom) van Loon Rajat Mazumder Shuvabrata De College of Earth Science and Engineering Shandong University of Science and Technology Geocom Consultants Department of Applied geology Faculty of Science and EngineeringCurtin University Sarawak Geological Studies division CSIR-National Geophysical Research Institute

Our contribution about a newly recognized sedimentological feature, which we called tombolith,has raised some comments on the etymology of the term, the assumed lack of field data, the usage of a term that has a special meaning in stratigraphy, the origin of the seismic shocks that played a role, so-called basic tenets, the origin of soft-sediment deformation structures, and the role of liquefaction. We argue that most comments result from an insufficiently thorough reading of our text, whereas some other remarks concern aspects that we did not deal with. Finally, several remarks are based on outdated literature and from insufficient knowledge of the regional geology.

关键词： Stromatolites Seismic shocks Palaeoproterozoic Singhbhum Craton Tomboliths India