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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, chinese 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

Malanite——A New Cupric Platinum (Pt^(3+)) and Iridium (Ir^(3+)) Sulphide

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Acta Geologica Sinica(English Edition) 1997年第2期71卷 152-157,233页

作者： Yu Zuxiang Institute of geology, chinese academy of Geological sciences, beijing, 100037 Institute of geology Chinese Academy of Geological Sciences Beijing 100037 [?]Yu Zhuxiang Born in Nov. 1930 graduated from the Specialty of Petrology and Mineralogy of the Department of geology Beijing College of Geology in 1953. He has long engaged in the study of mineralogy as Research Professor at the Institute of Geology Chinese Academy of Geological Sciences.

Malanite was first found in veinlets of disseminated copper-nickel ores inZunhua County, Hebei Province, and then in platinum-bearing chromite ores in ShuangfengVillage, Yanshan. In the former case, malanite appears as octahedrons or dodecahedrons asso-ciated with pyrrhotite, pentlandite, sperrylite and cooperite; while in the latter case, it is massiveor present in anhedral glomerocrysts, filling in cracks of iridisite and associated with osmiride,ferrian platinum and iridisite. Malanite is steel-grey in colour, opaque with metallic lustre andblack streaks and brittle with no magnetism. H_M=5.0, VHN_(20)=417kg/mm^2, cleavage {111}sometimes observed. The calculated density is 7.5.g/cm^3. The reflective colour is white with alight green tint. Internal reflections are not observed. This mineral is isotropic, showing nobireflection or reflection pleochroism in air. By means of electron microprobe analysis, the em-pirical formula (based on 7 atoms) is expressed as (Cu_(0.93)Fe_(0.06))_(∑0.99)(Pt_(1.03)Ir_(0.66)Rh_(0.04)Pd_(0.03)Co_(0.20)Ni_(0.03))_(1.99)S_(4.03) or (Cu_(0.95.Fe_(0.07))_(∑1.02)(Pt_(1.37)Ir_(0.45.Co_(0.11)Rh_(0.08))_(∑2.01)S_(3.97). Five strongestlines (hkl, d, I) of X-ray powder diffraction data of malanite are 311,2.98(6); 400,2.48(5.;333, 1.90(7); 440, 1.75.10); 731, 1.29(5.. It was known on the basis of X-ray powder diffractiondata that malanite is cubic, and the space group is Fd3m with α=0.9940nm, V=0.9821(3)nm^3 and Z=4. The type material of malanite is deposited at the Geological Museum of China(GMC)s

关键词： new mineral malanite chrome ore

The high-resolution climate recorded in the δ^(18)O of Porites lutea from the Nansha Islands of China

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chinese Science Bulletin 2001年第24期46卷 2097-2102页

作者： YU Kefu, CHEN Tegu, HUANG Dingcheng, ZHAO Huanting, ZHONG Jinliang & LIU Dongsheng (LIU Tungsheng)South China Sea Institute of Oceanoiogy, chinese academy of sciences. Guangzhou 5.0301, China:geology and geophysics Institute. chinese academy of sciences, beijing 10002., China South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China geology and geophysics Institute Chinese Academy of Sciences Beijing China

A Porites lutea core from Yongshu Reef of Nansha Islands covering 5. years growth history was ana-ly/ed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ18O with the instrumental temperature indicated that the coral δ18O is a good indicator for sea surface temperature (SST) and air temperature (t). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Nino events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ18O, thus back up the understanding of the climate of Nansha Islands to 195.. far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.24‰decrease in skeletal δ18O.

关键词： Nansha Islands Porites lutea δ18O sea surface tem-perature East Asia monsoon.

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5. ZHAO Ping2, JIAN Zhimin3 & HE Jinhai4 1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002., China 2. Institute of Climate and Environment, chinese academy of Meteoro- logical sciences, {5. 100081, China 3. Laboratory of Marine geology, Tongji University, Shanghai 200092, China 4. Department of Atmospheric sciences, Nanjing Institute of Meteorol- ogy, Nanjing 210044, China 5. Graduate School of the chinese academy of sciences, {5. 100039, China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of the chinese academy of sciences Beijing 100039 China Institute of Climate and Environment Chinese Academy of Meteorological Sciences Beijing 100081 China Laboratory of Marine geology Tongji University Shanghai 200092 China Department of Atmospheric sciences Nanjing Institute of Meteorology Nanjing 210044 China

Using a global atmosphere-ocean coupled model with the present-day and 14 MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14 MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14 MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 40°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science China Earth sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2, XIONG Shangfa3 & HUANG Fengbao1 1. Nanjing Institute of geology and Paleontology,chinese academy of sciences,Nanjing 210008,China 2. Anthropology and Sociology Department,Santa Clara University,CA 95.5.,USA 3. Institute of geology and {5.,chinese academy of sciences,beijing 10002.,China Nanjing Institute of geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States Institute of geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5.00 a BP. Before 5.00 a BP, the vegetation was dominated by Aneurolepidium chinese-Stipa grandis grassland of C4 grasses. After 5.00 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 8720 a BP, the Aneurolepidium chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 8720 to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5.00 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 4200?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3000 and 2170 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2170 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Provincialism of the late Middle through middle Late Cambrian paraconodonts and protoconodonts

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chinese Science Bulletin 2001年第5期46卷 433-438页

作者： DONG XipingDepartment of geology, Peking University, beijing 100871, China Laboratory of Paleobiology & Stratigraphy, Nanjing Institute of geology and Palaeontology, chinese academy of sciences, Nanjing 210008, China Department of geology Peking University Beijing China Laboratory of Paleobiology & Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

Quantitative paleoprovincialism is studied, using a coefficient of similarity (CS) formula. The results indicate that the provincialism of the late Middle through middle Late Cambrian paraconodonts and protoconodonts did exist. The provincialism of Ordovician conodonts can be traced back to late Middle Cambrian. The North China Province and South China Province can be recognized in late Middle Cambrian, whereas the North China Province, South China Province and Balitca Province can be recognized respectively in early Late Cambrian and middle Late Cambrian. The possibility that the larger units of provincialism, i.e. Faunal Regions existed in the areas mentioned above is discussed. It is inferred that the Midcontinent Faunal Region and the Atlantic Faunal Region had existed in early Late Cambrian and middle Late Cambrian. The North China Province was the secondary unit of provincialism in the Midcontinent Faunal Region, while the Baltica Province was that in the Atlantic Faunal Region. The South China

关键词： paraconodonts and protoconodonts provincialism late Middle Cambrian through middle Late Cambrian.

High-temperature phases of pyrophyllite and their evolutionary characteristics

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chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. Changsha Institute of Geotectonics, chinese academy of sciences, Changsha 410013, China 2. Institute of geology, chinese academy of sciences, beijing 10002., China Changsha Institute of Ceotectonics Chinese Academy of Sciences Changsha China Institute of geology Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 115.℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1710℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

^(14)C measurement of forest soils in Dinghushan Biosphere Reserve

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chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou Institute of Geochemisry, chinese academy of sciences, Guangzhou 5.0640, China Institute of geology, chinese academy of sciences , beijing 10002., China South China Institute of Botany, chinese academy of sciences, Guangzhou 5.065., China Guannzhou Institute of Geochemisry Chinese Academy of Sciences Guanazhou China Institute of geology Chinese Academy of Sciences Beijing China South China Institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14C values of these profiles decrease with increasing of depth. The Δ14C values in 30—40 cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 5.0 years ago. The 14C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 425.a BP, which is consistent with historical documents. The penetrating depths of "bomb 14C" in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively.

关键词： Dinghushan forest soil 14C tracing 14C apparent age.

Genesis of ^(230)Th excess in basalts from mid-ocean ridges and ocean islands:Constraints from the global U-series isotope database and major and rare earth element geochemistry

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Science China Earth sciences 2010年第10期53卷 1486-1494页

作者： ZHANG GuoLiang1,2 & ZENG ZhiGang1 1 Key Laboratory of Marine geology and Environment,Institute of Oceanology,chinese academy of sciences,Qingdao 266071,China 2 Graduate University of chinese academy of sciences,{5. 100049,China 1. Key Laboratory of Marine geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Based on 230Th-238U disequilibrium and major element data from mid-ocean ridge basalts(MORBs) and ocean island basalts(OIBs),this study calculates mantle melting parameters,and thereby investigates the origin of 230Th excess.(230Th/238U) in global MORBs shows a positive correlation with Fe8,Po,Na8,and Fmelt(Fe8 and Na8 are FeO and Na2O contents respectively after correction for crustal fractionation relative to MgO = 8 wt%,Po=pressure of initial melting and Fmelt=degree of melt),while 230Th excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle ***,compared with the MORBs,higher(230Th/238U) in OIBs actually corresponds to a lower melting *** suggests that the 230Th excess in MORBs is controlled by mantle melting conditions,while the 230Th excess in OIBs is more likely related to the deep garnet *** vast majority of calculated initial melting pressures of MORBs with excess 230Th are between 1.0 and 2.5.GPa,which is consistent with the conclusion from experiments in recent years that DU>DTh for Al-clinopyroxene at pressures of >1.0 *** initial melting pressure of OIBs is 2.2-3.5.GPa(around the spinel-garnet transition zone),with their low excess 226Ra compared to MORBs also suggesting a deeper mantle ***,excess 230Th in MORBs and OIBs may be formed respectively in the spinel and garnet stability *** addition,there is no obvious correlation of K2O/TiO2 with(230Th/238U) and initial melting pressure(Po) of MORBs,so it is proposed that the melting depth producing excess 230Th does not tap the spinel-garnet transition *** and MORBs in both(230Th/238U) vs.K2O/TiO2 and(230Th/238U) *** plots fall in two distinct areas,indicating that the mineral phases which dominate their excess 230Th are ***/Yb-Ce curves of fast and slow ridge MORBs are similar,while,in comparison,the Ce/Yb-Ce curve for OIBs shows more influence from *** mechanism

关键词： excess 230Th clinopyroxene garnet spinel-lherzolite mid-ocean ridge ocean island