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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. {4. and {2.al School, lanzhou university,{3., china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences,{3., china 3. College of {4. Science & Technology, {14. Normal university,{12., china 1. resources and environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~{2.e/~4.e in almost all samples range from 0.82.Ra to 2.74.Ra, whereas^(4.)Ar/^({2.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~{2.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~{2.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3.4. ZHANG Hucai2. WANG Weiguo3.& AN Chenbang3.1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 2.0008, china 2. Nanjng Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 2.0008, china 3. environment and {3. College, lanzhou university,{14., china 4. beijing Normal {12., beijing 100875, china 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. environment and {2. College Lanzhou University Lanzhou 730000 China 4. beijing Normal university Beijing 100875 China

With the support of 18 AMS-14. data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 4..2.to 11 ka B.P. in the Jingning area. Over the period of 4.―2. ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2.0}ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

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Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2.3. Feng Zhaodong4.and Gong Huili1,2.1. MOE and Key Laboratory of resources {2. and GIS of beijing, beijing 10003., china 2. Key Laboratory of 3. information Acquisition and Application, The Capital Normal university, beijing 10003., china 3. Department of Economics & Management of Huizhou university, Huizhou 516007, china 4. Key Laboratory of Western china’s {2.al Systems, Ministry of Education, lanzhou university,{13., china) MOE and Key Laboratory of resources environment and GIS of {2. Beijing 100037 China Key Laboratory of 3. information Acquisition and Application The Capital Normal University Beijing 100037 China Department of Economics & Management of Huizhou university Huizhou 516007 China Key Laboratory of Western china’s environmental Systems Ministry of Education Lanzhou University Lanzhou 730000 China

Ages of the stratigraphic boundary MIS1/2.and MIS3.4.of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2.and MIS3.4.are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2.is 11.5 kaB.P. and MIS3.4.is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2. 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14. age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

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Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3. WANG Pengxin4. YANG Hua1,2.3. LIU Shaomin1,2.3.& WANG Jindi1,2.3.1. Research Center for Remote Sensing and GIS, School of Geography, beijing Normal university, beijing 100875,{3. 2. State Key Laboratory of Remote Sensing Science, beijing 100875,{3. 3. beijing Key Laboratory for Remote Sensing of {12. and Digital Cities, beijing 100875,{3. 4. Department of Information Management, College of Information and Electronic Engineering,{3. Agricultural university, beijing 100083.{3. 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. beijing Key Laboratory for Remote Sensing of {2. and Digital Cities Beijing 100875 China 4. Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

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Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2. LU Yuanzheng1,2.3.& XU Daoyi4.1. Research Institute of Petroleum Exploration and Development, beijing 100083. china 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, beijing 100083. china 3. china university of Geosciences, beijing 100083. china 4. Institute of Geology, china Earthquake Administration, beijing 10002., china 1. Research Institute of Petroleum Exploration and Development 100083 Beijing China 2. Key Laboratory of Oil and Gas Reservoir of Petrochina 100083 Beijing China 3. china {2. of Geosciences 100083 Beijing China 4. Institute of Geology China Earthquake Administration 100029 Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence.{3. has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs 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, {2. Normal {3.,{4., 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 61004., china 4. Department of Physics, Sichuan Union {3., Chengdu 61004., 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-13. (13.Cs) 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 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 98{4.11 and {4.3.6.04.Bq · m-{4.wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 4. 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 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.

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Preliminary study on interaction between plant frictional root and rock-soil mass

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Science china(Technological Sciences) 2010年第7期53卷 1938-1942页

作者： YAN ZhiXin1’2. SONG Yun3. JIANG Ping1’2.& WANG HouYu4.1 Key Laboratory of Mechanics on Disaster and environment in Western{2. (lanzhou {3.), Ministry of Education, lanzhou 730000,{2. 2.School of Civil Engineering and Mechanics, lanzhou university, lanzhou 730000,{2. 3.College of Civil Engineering and Mechanics, Central South {3. of Forestry and Technology, Changsha 4.0004.{2. 4.Air Force Engineering Design & Research Bureau, beijing 100077,{2. 1. Key Laboratory of Mechanics on Disaster and environment in Western china ({2. {3.) Ministry of Education Lanzhou 730000 China2. School of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China3. College of Civil Engineering and Mechanics Central South University of Forestry and Technology Changsha 410004 China4. Air Force Engineering Design & Research Bureau Beijing 100077 China

The interaction between lateral root system of woody plant and soil mass is similar to the one between shrub, herbage and soil mass, and has the effect of frictional reinforcement on slope soil. It plays an important role in reinforcing soil strength in shallow slope. Therefore, slope soil mass can be considered as a composite of soil and plant roots and the soil strength and stability of shallow slope soil mass are improved. However, current researches still remain on the level of qualitatively analyzing the relation between root and soil mass. In this paper, some exploratory researches on quantitative analysis of the interaction mechanism between root and soil mass are conducted. With the study of interaction between herbage root system (lateral root system of woody plants) and soil mass, the mechanical model of interaction between frictional root and soil mass is established. The accuracy of the model is verified by field experiments of Pinus Yunnanensis. The mechanical model provides a crucial theoretical guidance to quantitatively analyzing the interaction between plant root and soil mass; it also has certain values in application.

关键词： plant slope protection vegetation for slope protection mechanical model frictional root

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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, {2. 100101,{4. 2.{4. university of Geosciences, {2. 100083.{4. 3. {2. Normal university,{12.,{4. 4. Bureau of Hydrology of Yellow River Conservancy Commission, Zhengzhou 4.0003.{4. 5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province, Xining 810001,{4. 1. Institute of Geographic Sciences and Natural resources Research Chinese Academy of Sciences 100101 Beijing China2. China University of Geosciences 100083 Beijing China3. Beijing Normal University 100875 Beijing China4. Bureau of Hydrology of Yellow River Conservancy Commission 450003 Zhengzhou China5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province 810001 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{2. 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.

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Research progress in studies on the coalbed gas geochemistry

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Progress in Natural Science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (College of resources Sciences & Technology, beijing Normal {2.,{3.,{4. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, lanzhou 730000,{4.) [a]College of resources Sciences & Technology Beijing Normal University Beijing China [b]Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Lanzhou China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13.1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4.values available for utilization vary from - 3.3. to - 117‰, and δ13.CO{4.values from - {4.. 4. to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13.1 and δ13.CO{4.values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13.1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.

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The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth Sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3. LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4.1. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 10002.,{2. 2. Institute of Geophysics,{2. Seismological Bureau, beijing 100085,{2. 3. Institute of Deposition Resource, Chinese Academy of Geosciences, beijing 10003.,{2. 4. School of Exploration and Information,{2. {14. of Geosciences, beijing 100083.{2. 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Institute of Geophysics China Seismological Bureau 100085 Beijing China 3. Institute of Deposition Resource Chinese Academy of Geosciences 100037 Beijing China 4. School of Exploration and Information China University of Geosciences 100083 Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3.segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2.km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2.segments. In the studied area, crustal thickness is about 4. km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural {2. of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

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