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Modeling of 3-D terrain effect on MT field using BEM

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Chinese Science Bulletin 1997年第9期42卷 764-767页

作者： XU Shizhe, RUAN Baiyao, ZHOU Hui and CHEN Leshou1.Institute of Geology and Geophysics, Ocean university of Qingdao, Qingdao 2.6003, china {2., beijing 100083, china Institute of Geology and Geophysics Ocean University of Qingdao Qingdao China Chi university of geosciences Beijing China

THE modeling of 2.D terrain effect on magnetotelluric(MT)has been solved using finite ele-ment method(FEM)and boundary element method(BEM).This note uses BEM tosolve the *** solution of H_x- and E_x-polarization wave ... 详细信息

关键词： MT 3-D terrain boundary element method.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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Science china Earth Sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2.& ZHOU Hui3 1. Laboratory of Material in the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. Department of Geology, china {2. of geosciences, beijing 100083, china 3. Department of Geology, Peking {2., beijing 100871, china Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang China Department of Geology China University of Geosciences Beijing China Department of Geology Peking University Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12.2.0 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12.h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12.2.0 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12.h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

Geochemical simulation of the formation of brine and salt minerals based on Pitzer model in Caka Salt Lake

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Science china Earth Sciences 2004年第8期47卷 720-726页

作者： LIU Xingqi1, CAI Keqin2.& YU Shengsong3 1. Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 2.0008, china 2. china university of geosciences,{2., china 3. Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, china Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China china university of {2. Beijing China Institute of Salt Lakes Chinese Academy of Sciences Xining China

The geochemical simulation of the formation of brine and salt minerals based on Pitzer model was made in Caka Salt Lake. The evolution of the mixed surface-water and the mineral sequences were calculated and compared with the hydrochemical compositions of the brine and the salt minerals of the deposit in Caka Salt Lake. The results show that the formation temperature of the lake is between 0°C and 5°C, which is well identical with other studies. The mixing of salt-karst water with the surface waters, neglected by the former researchers, is very important to the formation of the lake, indicating that the initial waters resulting in the formation of the lake are multi-source. It is the first time to use Pitzer model in china for making geochemical simulation of the formation and evolution of inland salt lake and satisfactory results have been achieved.

关键词： Pitzer model,Caka Salt Lake,geochemical simulation,salt-karst water.

Study on the changes of water cycle and its impacts in the source region of the Yellow River

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Science china(Technological Sciences) 2004年第Z1期47卷 142-151页

作者： ZHANG Shifeng1, JIA Shaofeng1, LIU Changming1, CAO Wenbing2. HAO Fanghua3, LIU Jiuyu4 & YAN Huayun5 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china {2., beijing 100083, china 3. beijing Normal university, beijing 100875, china 4. Bureau of Hydrology of Yellow River Conservancy Commission, Zhengzhou 450003, china 5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province, Xining 810001, china Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China china university of {2. Beijing China beijing Normal university Beijing China Bureau of Hydrology of Yellow River Conservancy Commission Zhengzhou China Bureau of Hydrology and Water Resource Investigation of Qinghai Province Xining China

The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of china in the 2.st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

关键词： source region of the Yellow River, water cycle, evaporation, negative equilibrium.

Characteristics of fluid inclusion planes and dynamical mechanism of structure-fluid-ore-forming processes in Yindongpo gold deposit, Henan Province, china

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Chinese Science Bulletin 1999年第S2期44卷 150-152页

作者： WEI Changshan~1, ZHAI Yusheng~2.and GHI Sanchuan~2.1. Yichang Institute of Geology and Mineral Resources, Chinese Academy of Geoscience, Yichang 443003, china 2. china university of geosciences,{2., china Yichang Institute of Geology and Mineral Resources Chinese Academy of Geoscience Yichang 443003 China china university of {2. Beijing 100083 China

THE Yindongpo gold deposit, situated in northern Tongbei County, northern Qinling orogenic belt, is alarge-scale one controlled by the Heqianzhuang anticline that plunges northwestwards and dips northeastwards. The ore-bodies locates in the carbon layers belonging to the Neoproterozoic Waitoushan *** ore-forming periods can be distinguished: the pre-Mesozoic epithermal mineralization in primary sediment with metamorphic superposition and the Mesozoic epithermal-mesothermal mineralization related totectonomagmatic activities. The principal ore-forming period can be divided into four stages. The ore bodies consist of networked and brecciated quartz veins. Gold is mainly rich in the veinlet-type quartz veinsthat formed during the diagentic-metamorphism or syn-metamorphic hydrothermal period, but a little inthe coarse veins related to later tectonomagmatic activities. The phenomenon that the fracturing degree

关键词： fluid inclusion planes dynamical mechanism structure-fluid-ore-forming processes gold deposit Yindongpo Henan.

Southeastern extension of the Red River fault zone (RRFZ) and its tectonic evolution significance in western South china Sea

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Science china Earth Sciences 2006年第8期49卷 839-850页

作者： LIU Baoming1,2.3, XIA Bin1, LI Xuxuan1,3, ZHANG Minqiang1,3, NIU Binhua2. ZHONG Lifeng1, JIN Qinghuan1,4 & JI Shaocheng1,5 1. Key Laboratory of Marginal Sea Geology and Resources, Chinese Academy of Sciences,Guangzhou 510640, china 2. china university of geosciences ({2.), beijing 100083, china 3. Research Center of Science & Technology Department, CNOOC, {2. 10002., china 4. Guangzhou Marine Geological Survey, Ministry of Land & Resources, Guangzhou 510075, china 5. Ecole Polytechnique Montreal, H3C3A7, Canada Key Laboratory of Marginal Sea Geology and Resources Chinese Academy of Sciences Guangzhou China china university of {2. (beijing) Beijing China Research Center of Science & Technology Department CNOOC Beijing China Guangzhou Marine Geological Survey Ministry of Land & Resources Guangzhou China Ecole Polytechnique Montreal Canada

Recent geophysical surveys and basin modeling suggest that the No.1 fault in the Ying- gehai basin (YGHB) is the seaward elongation of the Red River fault zone (RRFZ) in the South china Sea (SCS). The RRFZ, which separates the South china and Indo{2. block, extends first along the Yuedong fault, offshore of Vietnam, and then continues southward and breaks off into two branches: the Lupar fault and the Tinjia fault. The southern extension of the Lupar fault dies out beneath the NW Borneo while the Tinjia fault extends southeast and reaches the Brunei-Sabah area. According to the gravity and geomagnetic data, and the tectonic evolution of the basins, there are different evolution histories between the Wan’an basin (WAB) and the basins in the Nansha block. The Tinjia fault may be the boundary between the Balingian block and the Nansha block. Hence, the line linking the Yue- dong fault and the Tinjia fault, which both are continental margin faults and strike-slip ones in the geological evolution histories, constitute the boundary between the Indo{2. and Nansha block. The Lupar fault, in contrast, is an intraplate fault within the Indo{2. block. The results provide new hints for reconstructing the tectonic evolution history of the RRFZ and the opening of the SCS, and also a framework for hydrocarbon prospecting in the region.

关键词： Red River fault zone, tectonic evolution, fault, extension, western South china Sea.

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深海碳酸盐岩心天然热释光变化特征

海洋学报 2005年第1期27卷 78-83页

作者：刘海生方念乔艾星涛马万云陈瓞延清华大学物理系原子分子纳米科学教育部重点实验室北京100084 中国地质大学北京100083

东北印度洋赤道90°E海岭和孟加拉扇MD81349,MD77181岩心记录了30万a来气候变化的历史.分析发现浮游有孔虫壳体(方解石晶体)的天然热释光变化与δ18O反映的冰川旋回存在着良好的一致性:天然热释光强度的增大与间冰期对应,降低与冰期对应... 详细信息

东北印度洋赤道90°E海岭和孟加拉扇MD81349,MD77181岩心记录了30万a来气候变化的历史.分析发现浮游有孔虫壳体(方解石晶体)的天然热释光变化与δ18O反映的冰川旋回存在着良好的一致性:天然热释光强度的增大与间冰期对应,降低与冰期对应.对MD81349岩心天然热释光时间序列的频谱分析结果显示热释光的显著周期为99, 46, 2., 2.和11ka,其中99, 46, 2., 2.ka分别与天文学周期中的地球轨道偏心率周期100ka,地轴倾斜度(黄赤交角)周期54, 41ka,太阳辐射年度差异的岁差周期2., 19ka接近,这表明地球冷暖交替与太阳辐射强度周期性变化密切相关,在不同海水温度条件下结晶形成的方解石晶体的热释光强度差异显著,因而有孔虫壳体积存的热释光能够反映地球气候的变化.

关键词：光变岩心热释光碳酸盐岩地球气候 δ^18O 地轴方解石晶体度条件周期

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藏北羌塘小盆湖-拉雄错砂金矿带地质特征

沉积与特提斯地质 2002年第4期22卷 10-16页

作者：贾保江廖忠礼成都地质矿产研究所四川成都610082

以小盆湖砂金矿床为典型的一系列砂金矿床、矿点在藏北羌塘中部构成一个呈东西向的砂金矿带,笔者1999年首次将其命名为"藏北羌塘小盆湖拉雄错砂金矿带"。通过对小盆湖砂金矿床基岩地质、地貌、第四纪地质、矿床类型、成因类型、矿体特... 详细信息

以小盆湖砂金矿床为典型的一系列砂金矿床、矿点在藏北羌塘中部构成一个呈东西向的砂金矿带,笔者1999年首次将其命名为"藏北羌塘小盆湖拉雄错砂金矿带"。通过对小盆湖砂金矿床基岩地质、地貌、第四纪地质、矿床类型、成因类型、矿体特征、砂金特征的全面介绍及与该带其它砂金矿床、矿点的对比,结合区域地质背景,认为前泥盆系阿木岗群和石炭系中的火山岩层位是主要矿源层。此后若干不同时期的沉积不整合界面,都表征着其下古风化壳、其上底部碎屑岩的含金物聚源区可以直接或经改造就近形成金矿矿床。羌塘中央隆起带及其两侧和东西方向石炭系分布区具有广阔的金矿找矿前景。

关键词：砂金矿床找矿前景地层西藏成因地质

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四川锦屏山地区新构造运动及地质灾害

沉积与特提斯地质 2003年第1期23卷 99-104页

作者：廖忠礼廖光宇楼雄英成都地质矿产研究所

文章通过对四川锦屏山地区区域地质概况、河流阶地、第四纪断层及老断层新活动、地震活动的研究,认为该地区自更新世以来,新构造运动较为强烈,由此造成的地质灾害主要有滑坡、崩塌、泥石流等。

关键词：四川锦屏山地区新构造运动地质灾害地震活动滑坡崩塌泥石流断层河流阶地