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Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin

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Science china Earth Sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3 & PENG Jian4.1 School of Water Resource and Hydropower, Sichuan University, Chengdu 610065, china 2 National Satellite Meteorological Center, china Meteorological administration, beijing 100081, china 3 institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china 4.School of Environmental Sciences, Peking University, beijing 100871, china School of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological Center China Meteorological Administration Beijing China institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China School of Environmental Sciences Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

A comparative analysis on two solar proton events

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Chinese Science Bulletin 2007年第1期52卷 47-51页

作者： LE GuiMing1,2,3,4. HAN YanBen2 & ZHANG YiJun3 1 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, china Meteorological administration, beijing 100081, china 2 National Astronomical Observatories, Chinese Academy of Sciences, beijing 100012, china 3 Chinese Academy of Meteorological Sciences, china Meteorological administration, beijing 100081, china 4.National Center for Space Weather, china Meteorological administration, beijing 100081, china Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration Beijing China National Astronomical Observatoires Chinese Academy of Sciences Beijing China Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing China

This paper presents a comparative analysis on the two Solar Proton Events (SPE), which occurred on 14.July 2000 (Bastille Day) and 28 October 2003 (28OCT03) respectively. It is found that although the peak flux of the latter seemed to be greater than that of the former based on geostationary observations, the maximum intensities of the energetic protons (>10 MeV and 30 MeV) during the Bastille Day event were all higher than those of the 28OCT03 event according to the interplanetary observations. Further analysis indicated that the quantity of the seed particles, which could be accelerated to the energies exceeding 10 and 30 MeV by the Coronal Mass Ejection (CME)-driven shock on 14.July 2000, was far larger than that of the 28OCT03 event. In the Bastille Day case, when the CME approached to the height around 14.R⊙, the CME-driven shock would reach its maximum capacity in accelerating the solar en- ergetic protons (>100 MeV). In contrast, on 28 October 2003, when CME approached to the height about 58R⊙, the CME-driven shock reached its highest potential in accelerating the solar energetic protons of the same category. At this moment, the peak flux (>100 MeV) was about 155 pfu, which was much lower than 355 pfu measured on 14.July 2000. This demonstrated that in the Bastille Day event, the quantity of the seed particles, which could be accelerated to the energy beyond 100 MeV, was significantly larger than its counterpart in the 28OCT03 case. Therefore, the peak flux of an SPE event depends not only on the interplanetary intensity of the solar energetic particles, but also on the velocity of the associated CME-driven shock, and the quantity of the seed particles as well as on the interplanetary magnetic en- vironment. This paper also reveals that the magnetic sheath associated with ICME on 28 October 2003 captured a large number of solar energetic protons, including those having energy greater than 100 MeV.

关键词：太阳质子 CME 太阳耀斑太阳系

Sulfide-melt inclusions in mantle xenoliths of Hannuoba,china

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Chinese Science Bulletin 1999年第2期44卷 166-170页

作者： XU Jiuhua , CHU Xuelei , ZHOU Yiming , DU YuanfuUniversity of Science and Technology beijing, beijing 100083, china china University of Geosciences( beijing) , beijing 100083, china The Research Center of Mineral Resources Exploration , beijing 100101, china institute of geology, Chinese Academy of Sciences, beijing 10002., china University of Science and Technology beijing Beijing China china University of Geosciences (beijing) Beijing China The Research Center of Mineral Resources Exploration Beijing China institute of geology Chinese Academy of Sciences Beijing China

Sulfide fluid incluision study on mantle xenoliths of Hannouba has been carried out by EPMA analysis. It is indicated that the Ni/Fe ratios of metal sulfides in sulfide-melt inclusions from Hannuoba seem to be related to host rocks. These data of lherzolite （pentlandite） are obviously higher than those of olivine pyroxenite （mainly pentlandite, partly pyrrhotine）. The LRM analysis shows that sulfur （H2S+SO2） occupies larger proportion in gas composition of CO2 fluid inclusions, generally more than mol 20 %. This may be related to sulfide inclusions which are frequently found.

关键词： mantle xenolith sulfide-melt inclusion EPMA.

A new inverse filtering method of gravity field

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Acta Oceanologica Sinica 1988年第3期7卷 421-434页

作者： JIN XIANGLONG and GAO ZHIQING Second institute of Oceanography, State Oceanic administration, Hangzhou, china institute of Marine {4., Ministry of {4. and Resources, Qingdao, china Second Inst. of Oceanography State Oceanic Administration Hangzhou China China

A new method for inversion of gravity field using the technique of inverse filtering is presented in this paper to calculate the structure of *** inversing gravity data of West Pacific and Okinawa Trough, it has been proven that the method of inverse filtering has many advantages, such as high accuracy, fast convergence rate, small memory space used and arbitrary reduction of sampling interval. This new method is convenient to minicomputer for solving the inverse problem of crustal structure.

关键词： A new inverse filtering method of gravity field

Gas formation mechanism of marine carbonate source rocks in china

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Science china Earth Sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2, ZHANG Mingjie3, WANG Hongjun1, WANG Yunpeng4.& QIN Yong5 1. Research institute of Petroleum Exploration & Development, Petrochina, beijing 100083, china 2. Petrochina Exploration & Production, beijing 100011, china 3. Department of geology, Lanzhou University, Lanzhou 730000, china 4. Guangzhou Geochemical institute, Chinese Academy of Sciences, Guangzhou 51064., china 5. china University of Mining and Technology, Xuzhou 221000, china Research institute of Petroleum Exploration & Development PetroChinaBeijin China Petrochina Exploration & Production Beijing China Department of geology Lanzhou University Lanzhou China Guangzhou Geochemical institute Chinese Academy of Sciences Guangzhou China china University of Mining and Technology Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the Chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.

Discovery of the budding phosphatized globular fossils from the Neoproterozoic Doushantuo Formation at Weng'an, Guizhou Province, china

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Progress in Natural Science:Materials International 2006年第10期16卷 1079-1083页

作者： LIU Pengju , YIN Chongyu and TANG Feng (institute of geology, Chinese Academy of Geological Sciences, beijing 100037, china) institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

There is much debate on biological affinities of the phosphatized globular fossils from the Neoproterozoic Doushantuo phosphorites at Weng’an, Guizhou Province. Here we report for the first time the budding structures of some of these globular fossils, which have previously been interpreted as the resting eggs and early cleavage embryos of metazoans. The budding structures are similar to the germinating tubes of the spore and zygote of living algae, suggesting that some globular fossils from the Doushantuo phosphorites bear affinity with algae. The present new information indicated various biological affinity of the phosphatized globular fossils from the Doushantuo phosphorites.

关键词： Neoproterozoic Donshantuo Formation globular fossil budding structure algae resting eggs embryos.

Exotic structure of the third excited state in^(21)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2,3, LIANG Yujie1,2,3, DENG Fuguo1,2,3, LIU Zuhua1,4.& ZHOU Hongyu1,2,3 1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, beijing Normal University, beijing 100875, china 2. institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal University, beijing 100875, china 3. beijing Radiation Center, beijing 100875, china 4. china institute of Atomic Energy, beijing 1024.3, china Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China institute of Low Energy Nuclear Physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China china institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2= of the third excited state in 21Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73% and 1/2=5.28 fm respectively. The P value and the contribution of the asymptotic part to the 1/2 are compared with those of several other low energy states in 21Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 20Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 21Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

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 University, beijing 100875, china Key Laboratory of Gas Geochemistry, institute of {4. and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, china) College of Resources Sciences and Technology Beijing Normal University Beijing 100875 China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 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 δ13C1 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 - 333‰ to - 117‰, and δ13CCO2 values from - 29. 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 δ13C1 and δ13CCO2 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 δ13C1 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.

Discussion on measurement and calculation principle of petrogenetic depth

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Chinese Science Bulletin 1999年第24期44卷 2293-2295页

作者： LU Guxian and LIU Ruixun institute of Geomechanics , Chinese Academy of Geological Sciences , beijing 100081 , china Department of geology, Peking University, beijing 100871, china institute of Geomechanics Chinese Academy of Geological Sciences Beiing China Department of geology Peking University Beijing China

Geologic and geophysical data certificate that lithosphere and its down rock behave as solid, therefore,it is better to measure petrogenetic and metallogenetic depth according to internal stress of solid states. Lithomechanic experiment found that the bigger the confining pressure, the bigger the tensile and shear strength of rocks,so rock can bear very high differential stress but it is not broken. Sibson put forward that the property of rocks under 10-15km of the surface changes from brittle to ductile (rather than from elastic to plastic). Rock with ductile de-

关键词： petrogenetic depth solid stress state tectono-original additional hydrostatic pressure rock strength.