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Magnetic properties of Jiaxian red clay sequences from northern Chinese Loess Plateau and its paleoclimatic significance

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Science china Earth Sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, CHANG Hong & SONG Yougui 1. SKLLQG, institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, china {2., Chinese Academy of Sciences, guangzhou 51064., china 1. Chinese Academy of Sciences SKLLQG Institute of Earth Environment 710075 Xi’an China 2. Chinese Academy of Sciences Guangzhou Institute of Geochemistry 510640 Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the Chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern Chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern Chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern Chinese Loess Plateau, and it should be more arid in northern Chinese Loess Plateau.

关键词： northern Chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

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Magmatic-hydrothermal Evolution and Mineralization Mechanisms of the Wangjiazhuang Cu(-Mo)Deposit in the Zouping Volcanic Basin,Shandong Province,china:Constraints from Fluid Inclusions

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 679-700页

作者： SHU Lei YANG Renchao SHEN Kun YANG Deping MAO guangzhou LI Min LIU Pengrui MA Xiaodong Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Gold Mineralization Processes and Resource Utilization MNR/Key Laboratory of Metallogenic Geological Processes and Resource UtilizationShandong Province/Shandong Institute of Geological SciencesJinan 250013China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

The Wangjiazhuang Cu(-Mo)deposit,located within the Zouping volcanic basin in western Shandong Province,china,is unique in this area for having an economic *** order to expound the metallogenetic characteristics of this porphyry-like hydrothermal deposit,a detailed fluid inclusion study has been conducted,employing the techniques of representative sampling,fluid inclusion petrography,microthermometry,Raman spectroscopy,LA-ICP-MS analysis of single fluid inclusions,as well as cathode fluorescence spectrometer analysis of host mineral *** deposit contains mainly two types of orebodies,***-dissemination-stockwork orebodies in the K-Si alteration zone and pegmatiticquartz sulfide veins above *** addition,minor breccia ore occurs *** types of fluid inclusions in the deposit and altered quartz monzonite are identified:L-type one-or two-phase aqueous inclusions,V-type vapor-rich inclusions with V/L ratios greater than 50%-90%,D-type multiphase fluid inclusions containing daughter minerals or solids and S-type silicate-bearing fluid inclusions containing mainly muscovite and *** petrography and fluid inclusion study has revealed a three-stage mineralization process,driven by magmatic-hydrothermal fluid activity,as ***,a hydrothermal fluid,separated from the parent magma,infiltrated into the quartz monzonite,resulting in its extensive K-Si alteration,as indicated by silicate-bearing fluid inclusions trapped in altered quartz *** is followed by the early mineralization,the formation of quartz veinlets and dissemination-stockwork *** the main mineralization stage,due to the participation and mixing of meteoric groundwater with magmatic-sourced hydrothermal fluid,the cooling and phase separation caused deposition of metals from the hydrothermal *** a result,the pegmatitic-quartz sulfide-vein ores *** the late mineralization stage,decreasing fluid salinity led to the formation of L-type aqueous

关键词： fluid inclusions fluid immiscibility mineralization mechanisms Wangjiazhuang Cu(-Mo)deposit

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Saline-alkali soil reclamation and utilization in china:progress and prospects

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 216-228页

作者： guangzhou WANG Gang NI Gu FENG Haley MBURRILL Jianfang LI Junling ZHANG Fusuo ZHANG State Key Laboratory of Nutrient Use and Management(SKLNUM) College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China The institute of Ecology and Evolution University of OregonEugeneOR97403USA

Soil salinity is a global threat to the productivity of arable land. With the impact of population growth and development of social economy in china, the area of arable land has been shrinking in recent decades and is approaching a critical threshold of 12. Mha, the minimum area for maintaining the national food security. Saline-alkaline land, as important backup reserve, has been receiving increased attention as an opportunity to expand land resources. This review first summarizes the general principles and technologies of saline soil reclamation to support plant growth, including leaching salts or blocking the rise of salts, and soil fertility enhancement to improve the buffering *** the progress in this area in china is described including the customization of technologies and practices used in different saline-alkali regions. Following the soil management strategies, the concept of selecting crops for saline soil is proposed. This encompasses halophyte planting, salt-tolerant crop breeding and the application of saline-adapted functional microorganisms to improve the adaptation of crops. Finally, the current problems and challenges are evaluate, and future research directions and prospects proposed for managing this major soil constraint.

关键词： Food security land reserve reclamation saline-alkali soil utilization

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Evaluation criteria for gas source rocks of marine carbonate in china

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Progress in Natural Science:Materials International 2005年第9期15卷 810-817页

作者： WANG Zhaoyun1**, ZHAO Wenzhi1 and WANG Yunpeng2.1. Research institute of Petroleum Exploration & Development,Petrochina, Beijing 100083,{2. 2. guangzhou institute of geochemistry, Chinese Academy of Sciences, guangzhou 51064.,{2.) Research institute of Petroleum Exploration & Development PetroChina Beijing 100083 China. guangzhou institute of {2. Chinese Academy of Sciences Guangzhou 510640 China

Hydrocarbon generating and expulsion simulation experiments are carried out using samples artifically matched between the acid-dissolved residue of relatively low-maturity limestone and the original sample. This work makes up for the insufficiency of source rock samples with high abundance of organic matters and low maturity in china. The organic carbon content of the 10 prepared samples varies between 0.15% and 0.74%. Pyrolysis data and simulation experiment results of hydrocarbon generating and expulsion, which were obtained by a high-temperature and high-pressure open system, indicate that the lower limit of organic carbon content for marine carbonate rock to generate and expel hydrocarbons is 0.2.%—0.31%. In combination with the numerical analysis of organic carbon in marine carbonate rocks from Tarim Basin, Sichuan Basin, Ordos Basin and North china, as well as the contribution of these gas source rocks to the discovered gas pools, we think that the organic carbon criterion for carbonate gas source rocks should be 0.3%.

关键词： carbonate gas source rock gas-generating efficiency evaluation criteria simulation experiment.

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Kinetics of early methane generation from Green River shale

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Chinese Science Bulletin 1998年第22期43卷 1908-1912页

作者： LIU Jinzhong\+1 and TANG Yongchun 2.1. Laboratory of Organic geochemistry, guangzhou {2. of geochemistry, Chinese Academy of Sciences, guangzhou 51064., china 2. Chevron Petroleum Technology Company, CA 90633, USA Laborarory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Chevron Petroleum Technology Company USA

During oil/gas exploration in an area, there is a question as to whether methane in the strata was generated \%in situ\% mainly by thermal degradation of local organic matter. The key to the question is whether the kerogen could produce methane of more than 80 mL/g TOC, when its \%R\%\-o increased from initial (0.36%) to current value of 0.70% during thermal evolution. The authors have made efforts to answer this question by the kinetics method. First, a series of pyrolysis experiments were carried out to obtain data of methane yield and \%R\%\-o evolution, from which kinetic parameters of methane and \%R\%\-o were derived; then these parameters were extrapolated to the geological condition and finally, a methane yield, 96 mL/g TOC, was predicted. The result suggests that from the view of hydrocarbon generation, methane in the seam should be from thermal degradation of local kerogen.

关键词： methane kinetics pyrolysis organic geochemistry.

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The Juancheng chondrite──A new meteorite falling recently in china

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Chinese Science Bulletin 1998年第21期43卷 1834-1837页

作者： CHEN Yongheng 1,2. WANG Daode+2.and WANG Ruitian+31. Department of Chemistry, guangzhou Normal University, guangzhou 510400,{2. 2. guangzhou institute of geochemistry, Chinese Academy of Sciences, guangzhou 51064.,{2. 3. Heze Bureau of Seismolo Department of Chemistry Guangzhou Normal University Guangzhou China guangzhou institute of {2. Chinese Academy of Sciences Guangzhou China Heze Bureau of Seismology Shandong Province Heze China

The Juancheng chondrite, a new meteorite falling recently in Juancheng County, Shandong Province, china, is classified as an H5 (S2. chondrite based on the compositions of olivine (Fa= 19.2. σ Fa=0.46) and low-Ca pyroxene (Fs=16.9, σ Fa=0.4). The plagioclase in the Juancheng chondrite is rich in CaO, indicating a relatively high metamorphic temperature the parent body underwent.

关键词： Juancheng ordinary chondrite new meteorite.

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Nitric Oxide Emission Following Wetting of Dry Soils in Subtropical Humid Forests

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Pedosphere 2009年第6期19卷 692-699页

作者： LI De-Jun and WANG Xin-Ming 2.State Key Laboratory of Organic geochemistry, guangzhou {2. of geochemistry, Chinese Academy of Sciences, guangzhou 51064. (china) [a]State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 (China)

Information about soil nitric oxide （NO） emissions from subtropical forests is quite limited, and even less is known about the pulse emission of NO when wetting soils after a long period of dryness. In this study, we measured NO fluxes following wetting of dry soft in a broadleaf forest and a pine forest in subtropical china. Large pulses of NO fluxes were observed after soil wetting in both forests. NO fluxes increased significantly within 0.5 h following wetting in both forests and reached peak 1 and 4 h after soil wetting in the pine forest and the broadleaf forest, respectively. In the broadleaf forest, averaged peak flux of NO pulses was 157 ng N m^-2.s^-1, which was 8 times the flux value before wetting, and in the pine forest, the averaged peak flux was 135 ng N m-2.s 1, which was 15.5 times the flux value before wetting. The total pulses-induced NO emissions during the dry season were roughly estimated to be 2..4 mg N m^-2.in the broadleaf forest and 2..2.mg N m^-2.in the pine forest or made up a proportion of 4.6% of the annual NO emission in the broadleaf forest and 5.3% in the pine forest.

关键词： dry season flux. NO. pulse subtropical china

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Hydrogen isotopic compositions, distributions and source signals of individual n-alkanes for some typical crude oils in Lunnan Oilfield, Tarim Basin, NW china

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Science china Earth Sciences 2005年第8期48卷 1220-1226页

作者： LU Hong1, LI Chao1, SUN Yongge1, PENG Ping’an1 & XIAO Zhongyao2.1. State Key Laboratory of Organic geochemistry, guangzhou {2. of geochemistry, Chinese Academy of Sciences, guangzhou51064., china 2. Tarim Research {2. of Exploration and Development of Petroleum, china Petroleum, Korla 841000, china 1. State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Tarim Research institute of Exploration and Development of Petroleum China Petroleum 841000 Korla China

Isotopic compositions of carbon-bound hydrogen in individual n-alkanes from sev-eral typical crude oil samples from Lunnan Oilfield, Tarim Basin, NW china, were firstly measured using newly developed gas chromatography-thermal conversion-isotope ratio mass spectrometry. The similar range of δ D of individual n-alkanes of crude oils among reservoirs of different geo-logical times reflects that hydrocarbons are all derived from the same marine depositional envi-ronment. Compared to the theoretic value (?150‰) and the reported δ D values (nC13―nC2., ?160‰―?90‰) of individual n-alkanes for Ordovician-sourced crude oils in the Canadian Wil-liston Basin, the hydrogen isotopic composition of individual n-alkanes in crude oils from Lunnan Oilfield is characterized by heavy hydrogen isotopic values (nC12.nC2., ?12.‰―?60‰). In terms of the factors that control the fractionation of hydrogen isotopes, relatively saline deposi-tional environment and higher thermal maturation were attributed to the heavy δ D values of in-dividual n-alkanes in crude oils from Lunnan Oilfield.

关键词： hydrogen isotopes, individual n-alkanes, distribution, hydrocarbon source, Lunnan Oilfield.

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Summary of the 11th Conference on Magnetic Confined Fusion Theory and Simulation

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Plasma Science and Technology 2024年第10期26卷 1-7页

作者： guangzhou HAO Jianqiang XU Youwen SUN Zhibin GUO Organizing Committee of the 11th Conference on Magnetic Confined Fusion Theory and Simulation Southwestern institute of Physics Chengdu 610041People’s Republic of China institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China State Key Laboratory of Nuclear Physics and Technology Fusion Simulation CenterSchool of PhysicsPeking UniversityBeijing 100871People’s Republic of China 不详

This conference report summarizes recent progress in plasma theory and simulation that was presented in contributed papers and discussions at the 11th Conference on Magnetic Confined Fusion Theory and Simulation(CMCFTS)held in Chengdu,china,2.–30 October,*** in various fields has been *** example,results on zonal flow generation by mode coupling,simulations of the key physics of divertor detachment,energetic particle effects on magnetohydrodynamic(MHD)modes in addition to ion-and electron-scale turbulence,physics of edge coherent modes and edge-localized modes,and the optimization of ion heating schemes as well as confinement scenarios using advanced integrated modeling are presented at the *** this conference,the scientific research groups were organized into six categories:(a)edge and divertor physics;(b)impurity,heating,and current drive;(c)energetic particle physics;(d)turbulent transport;(e)MHD instability;and(f)integrated modeling and code development.A summary of the highlighted progress in these working groups is presented.

关键词： magnetic confined fusion(MCF) theory and simulation modeling tokamak

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NaAlSi_3O_8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite

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Chinese Science Bulletin 2001年第13期46卷 1121-1126页

作者： XIE Xiande, CHEN Ming, WANG Deqiang & El Goresy A.1.guangzhou institute of {2., Chinese Academy of Sciences, guangzhou 51064., china 2. Max-Planck-institute fur Chemie, 5512. Mainz, Germany guangzhou institute of {2. Chinese Academy of Sciences Guangzhou 510640 China Max-Planck-institute für Chemie 55128 Mainz Germany

The Suizhou L6 chondrite contains a few very thin shock melt veins of 0.02.0.09 mm in width. In spite of small width of the veins, shock-induced high-pressure phases, such as coarse-grained NaAlSi3O8-hollandite, ringwoodite, majorite and fine-grained matrix majorite-pyropess have been discovered in these veins. NaAlSi3O8-hollandite, the high-pressure phase of plagioclase, in Suizhou shock veins occurs as a single phase mineral, no silicate glassy phase, such as albitic glass, was incorporated with it. The presence of above-mentioned high-pressure phases constrains the high pressure (up to 2.-2. GPa) and high temperature (up to 1900-2.00℃) regime in Suizhou shock veins, and indicates that the duration of high-pressure regime in the veins should be long enough (a few seconds) for phase transformation and crystallization of minerals under pressure. The discovery of the first natural single-phase crystalline NaAlSi3O8- holland-ite in Suizhou meteorite is of important significance in understanding the Earth’

关键词： high NaAlSi3O8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite

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