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Science China Earth sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2.& SU Li3.1 institute of {2., {2. Academy of {3. {4., beijing 10003., China 2.College of Earth {4., Jilin University, Changchun 13.061, China 3.The {3. Laboratory Center and State Key Laboratory of {3. Processes and Mineral Resources, China University of Geo- {4., beijing 100083. China 1. institute of geology Chinese Academy of Geological Sciences Beijing 100037 China2. College of Earth Sciences Jilin University Changchun 130061 China3. The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 4.7±4.Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.2.2.15 to 0.2.2.57, with εHf(t) values of 5.02.0.2., indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science China Earth sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2. KANG Shichang2.3.5, SUN Junying4.5, Paul A. Mayewski2.& QIN Dahe5 1. National Climate Center, China Meteorological Administration, {2. 100081, China 2. Climate Change institute, University of Maine, Orono, ME 04.69, USA 3. institute of Tibetan Plateau Research, chinese Academy of {4., {2. 100085, China 4. chinese Academy of Meteorological {4., {2. 100081, China 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering Research institute, chinese Academy of {4., Lanzhou 73.000, China 1. National Climate Center China Meteorological Administration 100081 Beijing China 2. Climate Change institute University of Maine 04469 Orono ME USA 3. institute of Tibetan Plateau Research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. chinese Academy of Meteorological sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 2.D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 2.D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (2.D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

The upper mantle structure of the Tibetan Plateau and its implication for the continent-continent collision

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Science China Earth sciences 2005年第8期48卷 1158-1164页

作者： WU Qingju1, ZENG Rongsheng1 & ZHAO Wenjin2.1. institute of Geophysics, China Earthquake Administration, beijing 100081, China 2. institute of {3., China Academy of {4. sciences, beijing 10003., China 1. institute of Geophysics China Earthquake Administration 100081 Beijing China 2. institute of geology China Academy of Geological Sciences 100037 Beijing China

The upper mantle structures of Himalayas-Tibet have been obtained from the mi-gration of receiver functions of the teleseismic events recorded by INDEPTH-III. The result of migration imaging shows a dipping interface subducting northward from the depth of 100 km to the 4.0-km discontinuity underneath southern Tibet. It indicates that the lithospheric mantle of the Indian continent had been detached from the crust and deeply subducted to the upper mantle of Eurasia during the Indo-Eurasian collision. This kind of continent-continent collision process is fundamentally different from the oceanic collision.

关键词： Tibetan Plateau, receiver function, upper mantle structures, Indo-Eurasian collision, dipping interface.

β-delayed proton decays near the proton drip line

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2., CHEN Yongshou 2., XU Furong 3., WANG Kun 4., PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. {2. of Modern Physics, chinese Academy of {3., Lanzhou 73.000, China 2. Nuclear Physics Department, China {2. of Atomic Energy, {4. 102.1}3. China 3. Department of Technical Physics, Peking University, {4. 100871, China 4. Shanghai {2. for Nuclear Research, Shanghai 2.1800, China 1. institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear Physics Department China Institute of Atomic Energy 102413 Beijing China 3. Department of Technical Physics Peking University 100871 Beijing China 4. Shanghai institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2.04. namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14.nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92.h as well as the predicted “waiting point” nuclei 89Ru and 9{2.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2. The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 14.Ho and 12.Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. ({2. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

The Mechanism of Structural Control of Ore Formation and Geochemical Characteristics in the Massive Sulfide Deposits of the Wushan Copper Ore Field,Jiangxi

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Acta Geologica Sinica(English Edition) 1990年第3期64卷 261-274页

作者： Liu Xun institute of Geomechanics, chinese Academy of {2. {3., {4. Zhang Zhongmin institute of Geomechanics Chinese Academy of Geological Sciences Beijing

The ore-controlling mechanism of the bedding fault system in the massive sulfide deposits of the Wushancopper orefield may be generalized as the control of ore deposition by optimum surface in an ore-formingstructural trap. The mechanism has three major features: (1) timing of mineralization; (2. positioning of hostformation; and (3. dependence of ore-controlling structure on properties of rocks. The 'optimum surface' is adivisional structural plane which marks obvious difference in physical, chemical and mechanical properties andis favorable for mineralization. It is also a unity of structures. lithofacies and orebodies. The structural and geochemical characteristics of the ore deposits indicate the migration trend of the ma-jor characteristic clements in the ore-controlling fault belt: elements with a small radius (Si, Fe, Mg and Al)moved towards and concentrated at the center of the belt while large-radius ones (Ca, K and Na) were remotefrom the center.

关键词： The Mechanism of Structural Control of Ore Formation and Geochemical Characteristics in the Massive Sulfide Deposits of the Wushan Copper Ore Field Jiangxi

The deep thermal characteristic of continental margin of the northern South China Sea

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chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. Graduate School, University of Science and Technology of China, chinese Academy of sciences,{2., China 2. {3. of {4., chinese Academy of sciences, beijing 10002., China Graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China institute of geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South China Sea. The analysis of heat flow value shows that margin heat flow in the northern South China Sea is relatively high setting, but the percentage of crustal heat flow is lower than 3.% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South China Sea terrestrial heat flow thermal structures.

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3.,HUANG Zhiqin 2. 3. {2.1. The Faculty of Geography and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan, China 2. institute of Mountain Hazards and Environment, chinese Academy of {3., Chengdu 6100{2., Sichuan, China 3. Graduate University of the chinese Academy of {3., beijing 1000{2., China {2. Information Center of Land and Resources Department of Sichuan Province, Chengdu 6100{2., Sichuan, China The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of the chinese Academy of sciences 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science China Earth sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3.1. institute of Oceanology, {2. Academy of {2., Qingdao 2.6071, China 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061, China 3. Graduate School of the {2. Academy of {2., beijing 10003., China 1. Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration 266061 Qingdao China 2. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School of the chinese Academy of {2. 100039 Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Chengdeite-A New Mineral of Ordered Natural Iron-iridium Alloy

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Acta Geologica Sinica(English Edition) 1996年第1期70卷 27-32,108页

作者： Yu Zuxiang institute of geology, {2. Academy of {3. {4., beijing

Chengdeite occurs in chromite orebodies in dunite as well as in placers in their neighbourhood. The mineral occurs as granular aggregates in association with inaglyite and in some cases occurs as graphic intergrowths with native iridium. It is opaque with a metallic lustre, colour steel-black, streak black,HM = 5.2. VHN50=4.2.kg/mm2. cleavage not observed, fracture not observed, strongly magnetic. Its reflection colour is bright white with a yellowish tint. It has no internal reflection, bireflectance or pleochrism, and shows *** chemical analyses were carried out by means of the electron microprobe. The mean percentages of the data obtained in the 13.analyses ares S 0.001, Fe 7.9, Ni 0.03. Co 0.03. Cu 0.83. As 0.02. Rh 0.19, Pd 0.00, Os 0.06, Ir 88.5, Ft 2.2.and Pb 0.00. The simplified formula is Ir3.e, which requires Ir 91.17 and Fe 8.83. the total being 100.00 (% ).Five strongest lines of X-ray powder diffraction (hkl, d, I)are: 111, 2.18 (80);2.0, 1.89 (60); 2.0, 1.3.0}(70);3.1, 1.14. (100);2.2.1.094.(80).Through indexing of the X-ray powder diffraction data, the mineral has been determined to be cubic with Pm 3., a = 0.3.92.5)nm, V = 0.054.3.m and Z = 1.

关键词： new mineral chengdeitc chromite ore

Ages and Compositions of the Precambrian High-grade Basement of the Qilian Terrane and Its Adjacent Areas

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 375-384页

作者： WAN Yusheng, XU Zhiqin, YANG Jingsui and ZHANG Jianxin institute of geology, {2. Academy of {3. {4., beijing 10003. institute of geology Chinese Academy of Geological Sciences Beijing 100037 [?]2.an Yusheng Born in 1958 graduated from China University of Geosciences in 1981 received the Ph.D. degree in 1993 now senior geologist at the institute of geology Chinese Academy of Geological Sciences engaged in the study of geochemistry. Tel: 010–683.84.1 e-mail: wanysh@***

Based on geological, chronological, geochemical and Nd isotopic studies of the high-grade basement of the Qilian terrane, the authors have drawn the following main conclusions: (1) the high-grade basement of the Qilian terrane consists mainly of meta-argillo-arenaceous rocks and granites and its bulk part was formed in the period of 0.8–1.0 Ga (the Jinningian period); (2. most of the meta-argillo-arenaceous rocks and granitic rocks have strong negative Eu and Ba anomalies (Eu/Eu*= 0.4.–0.71 and Ba/Ba*=0.16–0.64., with fDM and ENd (1.0 Ga) ranging from 1.87 to 2.2. Ga and from ?8.54.to ?4.06 respectively, showing relatively high maturity; and (3. the Jinningian granitic rocks are a typical product of continent-continent collision, being probably related to the formation of the supercontinent Rodinia. These studies, combined with the study of high-grade basement rocks near the Qilian terrane, suggest that before the Jinningian period, the Qilian-Qaidam northern-margin terrane and Dunhuang-Alxa terrane were separated from each other, belonging to different plate systems of the North China craton and Yangtze platform respectively. The Qilian orogenic belt was the same as or similar to the Qiling orogenic belt in terms of the geological evolution history at least before the Jinningian period.

关键词： Qilian terrane chronology Nd isotope geochemistry Precambrian basement