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chinese Science Bulletin 2007年第19期52卷 2680-2686页

作者： WANG HaiLei1,2,3, ZHENG MianPing1,2,3 & HUANG XiaoXing4 1 institute of Mineral Resources, chinese academy of geological sciences (CAGS), beijing 100037, china 2 R&D Center for Saline Lake and Epithermal Deposits, CAGS, beijing 100037, china 3 Open laboratory of Saline Lake Resourses and Environment, CAGS, beijing 100037, china 4 laboratory of Microbial Resources, institute of Microbiology, chinese academy of sciences, beijing 100081, china institute of Mineral Resources Chinese Academy of Geological Sciences (GAGS) Beijing 100037 China

The bacterium Thermus sp. TibetanG7, isolated from hot springs in Tibet, china, was examined for the ability to accumulate cesium from solutions. Environmental conditions were simulated and the effects of pH, K+, Na+ and K+-regimes were then studied to determine the possible role of the bacterium in the formation of cesium-bearing geyserite around these hot springs. In despite of the inhibition of K+ and Na+, the bacterium Thermus sp. TibetanG7 revealed noticeable accumulation of cesium from solutions, with maximum accumulations of 53.49 and 40.41 μmol Cesium/g cell dry weight in Na+ and K+ inhibition experiments, respectively. The accumulation of cesium by this microorganism is rapid, with 40%―50% accumulated within the first 5 min. K+-deficient cells showed a much higher capacity of cesium accu- mulation compared with K+-sufficient cells. It is evident that the bacteria within the genus thermus play a significant role in the cesium assembly. The formation of cesium-bearing geyserite is also considered.

关键词：铯元素沉积物硅华生物矿化

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2, LIU Yu2 & TAN Ming31. South china Sea institute of Oceanology, chinese academy of sciences. Guangzhou 510301, china 2. State Key laboratory of Loess and Quaternary geology, Earth Environmental institute, chinese academy of sciences, Xi’an 710075, china 3. institute of geology and Geophysics, chinese academy of sciences, beijing 100029, china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key laboratory of Loess and Quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Important Events and Chronological Framework of the Early Precambrian Granulite Terrain,Northwestern Hebei Province

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 466-479页

作者： Geng Yuansheng, Liu Dunyi and Song Biaoinstitute of geology, chinese academy of geological sciences, 26 Baiwanzhuang,beijing 100037, china institute of geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Beijing 100037 China [?]Geng Yuansheng Born in January 1950 got a master degree at the Changchun College of geology in 1981 long engaged in the study of Early Precambrian geology and metamorphic petrology now research professor at the institute of geology Chinese Academy of Geological Sciences.

Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been established. Basic lava eruption occurred in the span of 2868-2932 Ma, resulting in the formation of the early crust. The TTG magma emplacement took place c.2761 Ma ago. Subsequently basic magma intruded into the supracrustal rocks at 2650 Ma, resulting in crustal thickening. The thickening was enhanced at 2561-2503 Ma by the widespread intrusions of granodioritic magma. In the period of 2477-2461 Ma charnockite intruded, accompanied by regional granulite facies metamorphism. The second stage of granulite facies metamorphism occurred c. 2300 Ma ago, and finally pink granite intrusions at 2144-2087 Ma resulted in the formation of a granite zone.

关键词： geological event Early Precambrian geochronology granulite northwestern Hebei

^(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 510640, china institute of geology, chinese academy of sciences , beijing 100029, china South china institute of Botany, chinese academy of sciences, Guangzhou 510650, 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 1 560 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.

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, chinese academy of geological sciences, 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× 105-2000× 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

Geochemical characteristics and contemporary metallogenetic process of hot springs in Tengchong

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chinese Science Bulletin 1999年第S2期44卷 29-30页

作者： HU Yunzhong, WANG Haiping and ZHANG Tianle institute of Mineral Deposits, chinese academy of geological sciences, beijing 100037, china institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China

1 The Geochemical characteristics of hot spring systems THE characteristic element abundance value/concentration coefficients of the geochemical characteristics ofTengchong are: Au-6.10/4.07, As-7.13/3.96, Sb-1.25/6.23, Pb-30.87/2.47, Th-20.25/2.11, Cd-0.57/2.83; Li-40/2, Ti-1.30/2.89 (abundance unit: Au-1 × 10-9, the others-1 ×10-6 ). Generally, these 8 elements can reflect the characteristics of the metallogenetic process with magmatic hydrothermal activities in the area. The abundances of other 32 elements measured are similar tothose of the crust. Granite in the area belongs to the calc-poor granite. Compared with the granite abundance in theworld, Cr, Co, Th, Pb and Cd are the concentrated elements. Their change in the regional distributionshows that Ca, Na, Th, Zn and REE increase from north to south, but Mg, Ti, Ba, Cu, Li, V, Zr,

关键词： hot spring system hydrothermal activity contemporary metallogenetic process.

shrimp dating of the Bangong Lake SSZ-type ophiolite: Constraints on the closure time of ocean in the Bangong Lake-Nujiang River,northwestern Tibet

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chinese Science Bulletin 2007年第7期52卷 936-941页

作者： SHI RenDeng1,2 1 School of Earth and Space sciences, University of Science and Technology of china, Hefei 230026, china 2 institute of geology, chinese academy of geological sciences, beijing 100037, china (email: shird@***) School of Earth and Space sciences University of Science and Technology ofChina Hefei 230026 China

The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The shrimp U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12, MSWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.

关键词：西藏班公湖怒江缝合带古海洋闭合时期 SSZ型蛇绿岩 shrimp 测年

The crystal structure of (Fe_(4)Cr_(4)Ni)_(9)C_(4)

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Science china Earth sciences 2005年第3期48卷 338-345页

作者： SHI Nicheng1, MA Zhesheng1, XIONG Ming1, DAI Mingquan1, BAI Wenji2, FANG Qingsong2, YAN Binggang2 & YANG Jingsui2 1. X-ray Diffraction laboratory, china University of Geosciences, beijing 100083, china 2. institute of geology, chinese academy of geological sciences, beijing 100037, china 1. X-ray Diffraction laboratory China University of Geosciences 100083 Beijing China 2. institute of geology Chinese Academy of Geological Sciences 100037 Beijing China

(Fe4Cr4Ni)9C4 is a metal carbide mineral formed by combination of Fe, Cr and Ni with C. It occurs in a chromite deposit in the Luobusha ophiolite, Tibet. Based on the determina- tion of its crystal structure, the empirical formula is (Fe4.12Cr3.84Ni0.96)8.92C3.70 and the simplified formula is (Fe4Cr4Ni)4C9. The mineral is hexagonal with a = 1.38392(2) nm, c = 0.44690(9) nm, space group P63 m c, Z=6 and the calculated specific gravity Dx = 7.089 g/cm3. Fe, Cr and Ni occupy different crystallographic sites and their coordination numbers are approximately 12, forming an alternate stacking sequence of flat and puckered layers along the c axis. Some me- tallic atoms have a defect structure. The interatomic distances of Fe, Cr and Ni are 0.2525— 0.2666 nm, and the distances between Fe, Cr, Ni and C are 0.1893—0.2169 nm. The coordina- tion number of carbon is 6. It occurs in interstices of the metallic atoms Fe, Cr and Ni to form trigonal-prismatically coordinated polyhedra. These coordination polyhedra are linked with each other via shared corners or shared edges into a new type of metal carbide structure.

关键词： Luobusha of Tibet, metal carbide, crystal structure.

Primary Study on Quantitative Reconstruction of Middle-Late Eocene Climate in Jianghan Basin

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Journal of china University of Geosciences 2002年第3期13卷 252-259页

作者： Tong Guobang Liu Zhiming institute of Hydrogeology and Environmental geology, chinese academy of geological sciences, Zhengding 050803 Open laboratory of Saline Lake Resources and Environment, chinese academy of geological sciences, beijing 100037 Zheng Mianping institute of Mineral Resources, chinese academy of geological sciences, beijing 100037 Research & Development Center of Saline Lake and Epithermal Deposit, chinese academy of geological sciences, beijing 100037 Wang Weiming Nanjing institute of geology and Palaeontology, chinese academy of sciences, Nanjing 210008 institute of Hydrogeology and Environmental geology Chinese Academy of Geological Sciences Zhengding 050803 Open laboratory of Saline Lake Resources and Environment Chinese Academy of Geological Sciences Beijing 100037 institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 Research & Development Center of Saline Lake and Epithermal Deposit Chinese Academy of Geological Sciences Beijing 100037 Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008

This paper reports our primary effort in the quantitative reconstruction ofpaleoclimate based on the thrine in phytoecology of the affinity parent plants in the stratigraphicpollen records. The Eocene pollen data come from our former study on the Mingjia borehole 1 in theJianghan basin. The fluctuating trend in the parameter curve of climate shows that the climate inthe Middle Eocene in the Jianghan basin was more or less comparable with that of the present22°―26°N, characteristic of a humid, semi-humid central-southern subtropical climate. The annualtemperature at that time dropped by 1 ℃― 4 ℃ in the Late Eocene, approximately equal to that ofthe present 23°―28°N of northern-central subtropical climate. However, the climate composite atthat time, characterized by higher temperature, small annual range and big fluctuation inprecipitation, was quite different from the present one. The average temperature in January in theMiddle Eocene, higher than that of today, ranged between 5 ℃ and 9 ℃, indicating that no effect ofwinter monsoon occurred in the Middle Eocene, though such an effect may have occurred occasionallyin the Late Eocene. Major temperature decline is recognized at the depth of 2 100 m in the borehole,as was indicated by the decline in average January temperature, the increase in annual range, andthe increase in the deciduous broad-leaved types of trees in the spore-pollen assemblage. The sharpfluctuation in the annual precipitation, usually raging from 300 to 1 700 mm, was favorable for themigration and accumulation of salty deposit. When the precipitation was lower than 1 000 mm,ephemera shrub increased at the same depth as that of the salty deposit. It is, therefore, deducedthat the formation of the salty deposit was attributed mainly to the dry and hot environment in thehigh mountains and deep basins. The small annual precipitation and the intense fluctuation arefavorable for the sustainable accumulation of the salts, which is different from the present

关键词： quantitative reconstruction of paleoclimate annual range function ofthrine in phytoecology fuzzy mathematics eocene jianghan basin

geological Setting of the Porphyry Copper Deposit Series of china

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 59-73页

作者： Zhang Hongtao Rui Zongyao institute of Mineral Deposits, chinese academy of geological sciences, beijing Liu Linqun institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing

In accordance with the terms global minerogenic series, regional metallogenic series and ore depositsystem which are put forward here, metallogenic environments at different levels are discussed for theporphyry copper deposit series in china. It is considered that the porphyry copper deposits in china arecontrolled not only by the boundaries of convergent plates but, more importantly, by the boundaries ofintraplate divergent mobile belts and those between continental blocks. Besides, the emplacement ofhypabyssal and supper-hypabyssal calc-alkaline magmas and the temporal-spatial distribution of china'sporphyry copper deposits are governed by the superimposition of fracture systems of the pre-Alpine base-ments. Meso-Cenozoic cover and continental-margin new-born crust. Such a superimposition has also re-sulted in the polycyclicity of the mineralization.

关键词： Zhang geological Setting of the Porphyry Copper Deposit Series of china