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Some advancements in measurements of physical parameters of earth's material at high temperature and ultrahigh pressure

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chinese Science Bulletin 1997年第21期42卷 1807-1810页

作者： XIE Hongsen, ZHANG Yueming, GUO Jie, XU Ji’an, SONG Maoshuang, XU Yousheng and HOU Wei1. institute of geochemistry,{2., {3. 550002. China 2. institute of Earth Science, Academia Sinica, Taipei, China institute of geochemistry Chinese Academy of Sciences Guiyang China institute of Earth Science Academia Sinica Taipei China

IT is very important to measure physical parameters of minerals, rocks, melts and fluids athigh pressure and high temperature. The data from these experiments can provide materialsfor explanation of geophysical observations on large scale, and information of geochemicalfield. Therefore, we set up measurement methods on elastic wave velocity, electrical conduc-tivity and differential thermal analysis in YJ-3.00 ton press fitted with a wedge-type

关键词： physical parameters earth’s material high temperature and nltrahigh pressure.

Environmental records of lacustrine sediments in different time scales:Sediment grain size as an example

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Science China Earth sciences 2004年第10期47卷 954-960页

作者： CHEN Jing’an1, WAN Guojiang1, David Dian Zhang2. ZHANG Feng1 & HUANG Ronggui1 1. State Key Laboratory of Environmental geochemistry, institute of geochemistry,{3., guiyang 550002. China 2. Department of Geography and Geology, University of Hong Kong, Pokfulam Road, Hong Kong, China State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China Department of Geography and Geology University of Hong Kong Hong Kong China

Sediment grain size is a conventional proxy of climatic changes. Larger sediment grain size is often interpreted to indicate dry climate during lower lake level while smaller sedi- ment grain size implies wet climate during higher lake level. Through detailed study on sediment grain sizes in Lake Erhai and Lake Chenghai, this paper reveals the different indication signifi- cances of sediment grain sizes in different time scales, different resolution investigations. For long time-scale and low resolution (102. or 103.) studies, larger sediment grain size indicates lower lake level, smaller lake area and drier climate while smaller sediment grain size indicates higher lake level, larger lake area and wetter climate. For short time-scale and high resolution (a or 10a) studies, larger sediment grain size reflects more rainfall and wetter climate while smaller sediment grain size reflects less rainfall and drier climate. Environmental information revealed by lacustrine sediment records is often different in different time scales because of the variance of sedimentation resolution, sampling resolution and dating precision. Therefore, paleoclimate im- plications of environmental proxies in long time-scale and low resolution investigations could not be mechanically applied to short time-scale and high resolution studies. Only after synthetically analyzing the influence manner and extent of all factors on the sediment records in different time scales, can credible conclusions be obtained.

关键词： lacustrine sediment, environmental record, grain size, time scale.

Enrichment mechanism of gold during the process of lateritization in southern area of the Yuanmou ancient landmass, Yunnan, China

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chinese Science Bulletin 1999年第S2期44卷 90-91页

作者： SUN Chengxing~1, WANG Shijie~1, DAI Fusheng~2.and LUO Yi~2.1. State Key Laboratory of Environmental geochemistry, institute of geochemistry,{3., guiyang 550002. China 2. Department of Geology, Kunming University of Science and Technology, Kunming 650093. China State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Department of Geology Kunming University of Science and Technology Kunming 650093 China

SINCE the first discovery of lateritic gold deposit which is easier to mining and dressing at Boddington inWestern Australia at the beginning of the 1980s, geologists have paid much attention to it, and it wasfound in tropical and subtropical regions. However, recently the metallogenetic mechanism has notbeen understood very well. In this note we reported some research results on the enrichment mechanism ofgold during the process of lateritization in the case of three lateritic profiles with some degree of gold enrichment located in southern area of the Yuanmou ancient landmass, Yunnan Province. The parent rocks of the investigated profiles （about 5-8 m thick） is metamorphic schist, in whichmean content of gold is 13.3.10-9. Samples were collected from two pits at Xujie （Mouding County）and an outcrop of gully at Menglingou （Yuanmou County）, dried in air and ground in agate mortar to

关键词： gold enrichment lateritizafion Yunnan.

Proposal and prospects for the global Lower-Middle Cambrian boundary

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Progress in Natural Science:Materials International 2004年第12期 1-6页

作者： ZHAO Yuanlong 1*, YUAN Jinliang 2. PENG Shanchi 2. GUO Qingjun 3. ZHU Lijun 1, PENG Jin 1 and WANG Pingli 1(1. College of Resource and Environment of Guizhou University of Technology, guiyang 550003. China 2. Nanjing institute of Geology and Palaeontology, chinese academy of sciences, Nanjing 2.0008, China {3., chinese academy of sciences, guiyang 550002. China) CollegeofResourceandEnvironmentofGuizhouUniversityofTechnology Guiyang550003China NanjinginstituteofGeologyandPalaeontology ChineseAcademyofSciencesNanjing210008China instituteofgeochemistry ChineseAcademyofSciencesGuiyang550002China

In recent years paleontologists have been working on the global stratotype section and standard point (GSSP) for the Lower Middle Cambrian boundary in North America, China, Morocco, Spain and Russia. Continually, they suggest the potential first appearance datum (FAD) of the Middle Cambrian, such as Oryctocephalus indicus, Ovatoryctocara granulata, Acadoparadoxides mureroensis, Hupeolenus and Arthricocephalus chauveaui as being relevant to the potential stratotype section for the Lower Middle Cambrian boundary. There are only a few trilobites distributed widely enough in the Early to Middle Cambrian connection, so virtually no trilobite(s) can act as the FAD for the global Middle Cambrian. The easily identified Oryctocephalus indicus is widely distributed in three realms of the global Cambrian. Its first appearance position is linked to the extinction of old species coevolution of new ones. It appears to be a comparatively good FAD of Middle Cambrian. The continuous and unbroken Wuliu section (Balang, Taijiang County, Guizhou Province, China) includes O. indicus and co occurs with many benthic and nektonic trilobites. The evolution of acritarchs in the section, the changed characteristics of trace elements (REE and C isotopes) are generally consistent with the evolution of trilobites both above and below the boundary. Strata above the boundary yield the famous Kaili Biota. The Wuliu section is easily accessible from a main highway.

关键词： Lower-Middle Cambrian boundary GSSP Taijiang Wuliu section Oryctocephalus indicus FAD (first appearance datum).

Sulfur isotope geochemistry of the Lemachang independent Ag deposit, northeastern Yunnan——A concurrent discussion on the mechanism of sulfur isotope equilibrium between barite and freibergite below 3.0℃

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chinese Science Bulletin 1999年第S2期44卷 227-230页

作者： DENG Hailin~1, LI Chaoyang~1, ZHOU Yunman~2.and WANG Congwu~2.1. Open Laboratory of Ore Deposit geochemistry, institute of geochemistry,{3., guiyang 550002. China 2. No.3.Braneh of No.1 Geology Party, Yunnan Bureau of Geology and Mineral Resources, Xundian 6552.5, China Open Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China No. 3.Branch No. 1 Geology Party Yunnan Bureau of Geology and Mineral Resources Xundian 655205 China

IN the study of hydrothermal deposits sulfur isotopes bear much information about the source of sulfur,ore-forming temperature, the evolution of ore-forming fluids and the mechanism of metallogenesis. Todetermine whether sulfur isotopes reach equilibrium between fluids and sulfur-bearing minerals precipitated from the former and among the sulfur-bearing minerals is the key to the application of sulfur isotopegeochemistry to geological problems. As it has been commonly accepted that sulfur isotopic equilibrium could not be reached between sulfate and sulfide below 3.0℃, little attention has been paid to thepossible mechanism of sulfur isotope equilibrium between sulfate and sulfide below 3.0℃. However, this note presents an example to show sulfur isotope equilibrium between barite and sulfate

关键词： sulfur isotope Lemachang independent Ag deposit barite freibergite sulfur isotope equilibrium below 3.0℃.

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超声实验中谱比法衰减的散射与本征吸收特性

地球物理学报 2018年第3期61卷 1083-1094页

作者：周浩符力耘矿产地球化学国家重点实验室中国科学院地球化学研究所贵阳550002 中国科学院大学北京100049 中国石油大学(华东)地球科学与技术学院青岛266580

实际地球介质的弹性波衰减,无论是对于地球内部结构反演、含油气储层描述,还是对于地震岩石物理本身的基础研究而言,都十分重要.通过岩石物理实验测量岩石的弹性波衰减是相关研究的基本手段,而谱比法是一种最常用的测量方法.利用谱比法... 详细信息

实际地球介质的弹性波衰减,无论是对于地球内部结构反演、含油气储层描述,还是对于地震岩石物理本身的基础研究而言,都十分重要.通过岩石物理实验测量岩石的弹性波衰减是相关研究的基本手段,而谱比法是一种最常用的测量方法.利用谱比法测量的弹性波衰减,简称谱比法衰减,由介质的本征吸收特性和非均质散射特性共同决定.然而,在谱比法理论中,没有将这两种衰减特性的作用区分对待.因此,实验室测量的谱比法衰减中是否含有散射特性,其散射特性是否可以忽略,常不明确.本文基于对岩石物理实验中样品波形特征的基本认识,通过能流理论描述了弹性波的本征吸收和非均质散射过程,以及对应的尾波形成机理.文章还应用能流理论测量岩石的弹性波衰减,即能流法衰减.无论是通过理论推导,还是通过实验验证,谱比法衰减与能流法衰减都显示出良好的一致性.这两种直达波衰减的一致性暗示了谱比法衰减中存在着两种衰减特性.文中还对比分析了谱比法衰减与喷射流本征衰减的实验结果,该结果同样展示了谱比法衰减中可能存在着散射特性.因此,通过能流理论,可以利用样品波形的尾波特征定性判断谱比法衰减中可能存在的散射特性.即异常明显的尾波振幅可能意味着强烈的直达波非均质散射,谱比法衰减中的散射特性因而不可忽略.

关键词：谱比法散射衰减本征衰减尾波

The seasonal and daily CO_2.concentration variance in karst meadow soil profile with depth in Central Guizhou, China

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chinese Science Bulletin 1999年第S2期44卷 93-94页

作者： ZHENG Leping~(1,2., LI Tingyu~2. WAN Guojiang~2. WANG Shijie~2.and OUYANG Ziyuan~2.1. Department of Environmental Science and Engineering, Shanghai University, Shanghai 2.0072. China 2. State Key Laboratory of Environmental geochemistry, institute of geochemistry,{3., guiyang 550002. China Department of Environmental Science and Engineering Shanghai University Shanghai 200072 China State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE seasonal variance of soil CO2.concentration with depth in soil profile was widely studied. Few similarresearches on this topic have been done in karst area which comprises 15% global terrestrial area. In thisnote,... 详细信息

THE seasonal variance of soil CO2./sub> concentration with depth in soil profile was widely studied. Few similarresearches on this topic have been done in karst area which comprises 15% global terrestrial area. In thisnote, the research results about the seasonal and daily soil CO2./sub> concentration variance in karst area arereported. The soil gases were collected respectively by the sampling device at 2.0, 5,0, -5, -10,-15, -2., -3. and -45 cm from the land surface in meadow soil profile described by Zheng andlocated in the Hongfeng lake area in the central Guizhou Plateau which lies in the central East-Asia karstarea. Sampling time is in the morning, midday and at night in April, August and November, 1998 aswell as in January, 1999, respectively. Concentrations （volume percent） of CO2./sub> in soil gas samples

关键词： soil CO2 concentration karst area Guizhou Province.

Ge-rich hydrothermal solutions and abnormal enrichment of Ge in coal

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chinese Science Bulletin 1999年第S2期44卷 257-258页

作者： HU Ruizhong, BI Xianwu, SU Wenchao, QI Huawen and YE Zaojun Intitue of geochemistry, chinese academy of sciences, {2. {3. China institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

AT present, the main source of germanium includes two types of ore deposits: some sulfide-rich Pb, Zn,Cu, Ag and An deposits and some coal deposits. Germanium occurs as an associated element in these oredeposits. The Lincang germanium deposit discovered recently in China occurs in a basin where there areexposed the Neogene coal-bearing clastic rocks with Indosinian Ge-rich (（1.9-5.0）×10-6) granitesas the basement in Lincang County, Yunnan Province. Germanium is mainly concentrated in the coalseams of the first coal-bearing horizon (Nth2./sup>) and in regard to its grade (normally n×100×10-6 with themaximum over 1000×10-6) and scale （the proven reserve about 800 t）, no such germanium mineralization has been reported so far in other parts of the world. What is the reason? The available studies have indicated that this germanium deposit is of epigenetic origin, whichdetermines that germanium must have been transferred into coal with the help of a kind of medium. It isnoticed that （i） organic germanium in natural waters is stable and it is never involved in its

关键词： coal. abnormal enrichment of germanium Ge-rich hydrothermal solution.

CHARACTERISTICS AND METALLOGENIC EVOLUTION OF AILAOSHAN GOLD METALLOGENIC BELTS IN YUNNAN, CHINA

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地学前缘 2000年第S1期7卷 404-405页

作者： Fang Weixuan, Hu Ruizhong, Bi Xianwu, Su Wenchao[WT5,5”BX](institute of geochemistry,{2., {3. 550002.China)

Observations made in different superlarge\|large gold deposits in Ailaoshan gold metallogenic belts, Yunnan Province, China, on the eastern margin of the Qingzang (Himalayas—Karakoram—Tibet) were investigated. Geotectonically, the study area is situated in the conjoint between the Tethys and Himalayas tectonic domain, characterized by very complex geological structure, with strongly influenced by the Himalayas in late development.1\ Regional geology and gold deposits\;Ailaoshan gold metallogenic belts is localized between Ailaoshan super lithospheric faults and Jiujia—Anding brittle\|ductile shear zone, with NNW\|trending about 2.0km long. To southward, Zhenyuan supergiant gold deposits, Mojiang large gold deposits, and Daping giant gold deposits hosted in low metamorphic volcanic\|sedimentary rocks (D—C). Ore types include gold\|bearing quartz veins, gold\|bearing altered rocks, and the mixing of the two types. Most of gold orebodies took their positions in the substructures of the brittle\|ductile shear zone.

关键词： gold deposits Ailaoshan gold metallogenic belts Yunnan geoc hemical anomaly mineral assemblages geochemical characteristics evolutions of gold mineralization