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chinese Science Bulletin 2000年第8期45卷 753-758页

作者： Yunpeng Dong bingquan Zhu chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China

Based on the geological mapping, it is suggested that the pillow lavas exposed in Jianshui area in southeastern Yunnan Province are emplaced into the western part of Shizong-Mile faults, the boundary between the Yangtze and Cathaysian blocks, and mainly composed of tectonic massive of basalts and basaltic andsites. The geological and geochemical studies show that these lavas erupted in an island arc tectonic setting, which suggests that there existed the subduction of oceanic crust between the Yangtze and Cathaysian blocks. The paleontological fossils in the sedimentary interlayers between the volcanic rocks indicate that these pillow lavas erupted during Carboniferous-Permian. The geologic and geochemical evidence suggested that there existed an eastern branch of Paleo-Tethys between the Yangtze and Cathaysian blocks in southeastern Yunnan, South China.

关键词： southeastern Yunnan Province island arc pillow lava geochemistry tectonic evolution.

Lithospheric thermal-rheological structures of the continental margin in the northern South China Sea

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chinese Science Bulletin 2000年第22期45卷 2107-2112页

作者： Xiaobin Shi Di Zhou Yixiang Zhang Open Laboratory of Marginal Sea Geology and Paleoenvironment South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

Thermal structures of three deep seismic profiles in the continental margin in the northern South China Sea are calculated, their 'thermal' lithospheric thicknesses are evaluated based on the basalt dry solidus, and their rheological structures are evaluated with linear frictional failure criterion and power-law creep equation. 'Thermal' lithosphere is about 90 km in thickness in shelf area, and thins toward the slope, lowers to 60-65 km in the lower slope, ocean crust and Xisha Trough. In the mid-west of the studied area, the lithospheric rheological structure in shelf area and Xisha Islands is of four layers: brittle, ductile, brittle and ductile. Because of uprising of heat mantle and thinning of crust and lithosphere in Xisha Trough, the bottom of the upper brittle layer is only buried at 16 km. In the eastern area, the bottom of the upper brittle layer in the north is buried at 20 km or so, while in lower slope and ocean crust, the rheological structure is of two layers of brittle and ductile, and

关键词： northern South China Sea “thermal” lithospheric thickness lithospheric rheological structure.

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , chinese academy of sciences , Beijing 100101, China 2. Institute of Geology , chinese academy of sciences , Beijing 100029, China 3. Institute of High Energy Physics , chinese academy of sciences , Beijing 100817 , China 4. Beijing University of Science and Engineering , Beijing 100083, China Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

MAJOR PROBLEMS OF SUSTAINABLE DEVELOPMENT ALONG THE BANK AREA OF THE CHANGJIANG RIVER

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chinese Geographical Science 2000年第2期10卷 97-104页

作者： YANG Gui-shan(Nanjing Institute of Geography and Limnology,the chinese academy of sciences, Nanjng 210008, P R. China) Nanjing Institute of Geography and Limnology the Chinese Academy of Sciences Nanjing P. R. China

Developing the Changjiang(Yangtze) River and building a developed economic zone along the bank area of the Chanajiang River is a great strategic decision of the national macroeconomic development distribution. This decision has both given an impetus to fast development of the regional economy and exacerbated the contradiction among economy and resources and environment. In this paper, some major problems ekisting in economic sustainable development, such as scattered industrial structure, duplicated construction of the great projects, enlarging the development gap of the regional economy and deteriorated environment etc., have been studied. The results show that scattered structure and duplicated distribution of some key industries and projects, especially automobile, electronics and petrochemical industry and communication, power installations, is one of the reasons for low industrial economic benefit; the great development gap among upper, middle and lower reaches areas are enlarging since the 1990’ s; soil erosion, nood disaster and environmental pollution are still exacerliating due to unreasonable over-development. Based on the above analysis, this paper brings out some countermeasures and proposals for increasing the ability of regional sustainable development, including transregional reorganization of industrial structure linking by assets and speeding the process of regional economy integration; gradually controlling and reducing the development gap arnong upper, middle and lower reaches areas through regional cooperation on a mutually beneficial basis; as well as strengthening ecological construction and environmental protection and increasing environmental bearing capacity etc.

关键词： the bank area of the Changjiang River sustainable development structure problems environment deterioration

Simulation study of discharge processes in thunderstorm

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chinese Science Bulletin 1999年第22期44卷 2098-2102页

作者： Yijun Zhang Muhong Yan Xinsheng Liu chinese Acad Sci Lanzhou Inst Plateau Atmospher Phys Lanzhou 730000 Peoples R China

The discharge characteristics in thunderstorm have been calculated by using a numerical cloud model. The results indicate that discharge processes occur when simulated thunderstorm developed at the stage of 30-45 min and initial locations of discharge mainly distributes between 4.4-4.8 km and 6.4-6.8 km above the ground (corresponding to ambient temperature of - 10℃ and -25℃. In simulated thunderstorm with a tripole electric structure,

关键词： thunderstorm discharge precipitation.

Oxygen isotopic (^(17)O-^(18)O) heterogeneity in Archaean continental nucleus, North China Craton

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chinese Science Bulletin 1999年第24期44卷 2267-2269页

作者： LIU Jianzhong, ZHANG Fuqin, LI Chunlai and WANG Shijie Institute of Geochemistry , chinese academy of sciences , Guiyang 550002 , China Institute of Geophysics , chinese academy of sciences , Beijing 100101 , China Institute of Geochemistry Chinese Academy of Sciences Guiyang China Institute of Geophysics Chinese Academy of Sciences Beijing China

The oxygen isotopic data for amphibolites from Archaean continental nucleus, North China Craton indicate that ( i ) the evolving lines structured by the data are parallel to the geoselenic evolving line, which means that the parent materials of these continental nucleus o-riginated from solar matter; ( ii ) different intercepts for these evolving lines manifest that oxy-

关键词： North China Craton oxygen isotope (I7O-18O ) heterogeneity.

The seasonal variations of δ^(18)O , Cl^- , Na^+ ,NO_3^- and Ca^(2+) in the snow and firn recovered from Princess Elizabeth Land, Antarctica

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chinese Science Bulletin 1999年第24期44卷 2270-2273页

作者： LI Zhongqin, ZHANG Mingjun, QIN Dahe, XIAO Cunde, TIAN Lide KANG Jiancheng and LI Jun Lanzhou Institute of Glaciology and Geocryology , chinese academy of sciences , Lanzhou 730000, China chinese Institute of Polar Research, Shanghai 200129, China Antarctic CRC and Australian Antarctic Division , Hobart, Australia Corresponding author Lanzhou Institute of Glaciology and Geocryology Chinese Academy of Sciences Lanzhou China chinese Institute of Polar Research Shanghai China Antarctic CRC and Australian Antarctic Division Hobart Australia

Snow and firn samples recovered from two snow pits (2.5 and 4.5m deep) and one 50-m firn core along the route of the 1996/1997 chinese First Antarctic Inland Traverse Expedition in Princess Elizabeth Land, East Antarctica, have been measured for chemical composition and oxygen isotope ratio. In the two snow pits, the variations of NO3- are partly in phase with that of δ18O, while the variations of Cl- and Na+ are in inverse phase with that of δ18O.

关键词： Princess Elizabeth Land ion δ18O seasonal variations.

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 137Cs technique

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chinese Science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of China, Beijing Normal University, Beijing 100875, China 2. Institute of Desert Research, chinese academy of sciences, Lanzhou 730000, China 3. Institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, China 4. Department of Physics, Sichuan Union University, Chengdu 610041, China Key Laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2 376.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5) suffered erosion only. By using 137Csmodel, the average wind erosion rates for shrub coppice

关键词： 137Cs technique Qinghai-Tibetan Plateau wind erosion.

Global change and climate-vegetation classification

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chinese Science Bulletin 2000年第7期45卷 577-585页

作者： Guangsheng Zhou Yuhui Wang chinese Acad Sci Inst Bot Lab Quantitat Vegetat Ecol Beijing 100093 Peoples R China

Three phrases of the quantitative study of climate-vegetation classification and their characteristics are presented based on the review of advance in climate-vegetation interaction, a key issue of 'global change and terrestrial ecosystems (GCTE)' which is the core project of International Geosphere-biosphere Programme (IGBP): (i) characterized by the correlation between natural vegetation types and climate; (? characterized by climatic indices which have obviously been restricted to plant ecophysiology; (iii) characterized by coupling both structure and function of vegetation. Thus, the prospective of climate-vegetation classification for global change study in China was proposed, especially the study coupling climate-vegetation classification models with atmospheric general circulation models (GCMs) was emphasized.

关键词： climate-vegetation interaction climate-vegetation classification atmospheric general circulation models global change.

Methane emissions from wetlands on the Qinghai-Tibet Plateau

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chinese Science Bulletin 1999年第24期44卷 2282-2286页

作者： Nakano Tomoko Department of Geography Tokyo Metropolitan University 192-03 Japan

The areal extent of cold freshwater wetlands on the Qinghai-Tibet Plateau (QTP) is estimated at 0.133 × 106 km2, suggesting a significant methane potential. Methane fluxes from wet alpine meadows, peatlands, Hippuris vulgaris mires and secondary marshes were 43.18, 12.96, -0.28 and 45.90 mgf33m-2f33d-1, respectively based on the transect flux studies at the Huashixia Permafrost Station (HPS) from July to August 1996. Average CH4 fluxes in the

关键词： QTP wetland ecosystems CH4 emission spatiality and seasonality fluxes.