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801.
First Occurrence of M andarinoite in China 总被引:6,自引:0,他引:6
Harvey E. BELKIN National Center U.S. Geological Survey Reston VA - USAE-mail: hbelkin@usgs.gov ZHENG Baoshan ZHU JianmingState Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou China 《《地质学报》英文版》2003,77(2):169-172
This report describes the first occurrence of the rare mineral mandarinoite (Fe3+2 Se3Og · 6H2O) in China. It occurs in the Lower Permian Maokou Formation carbonaceous shale in Yutangba Village east of Enshi City in southwestern Hubei Province. The shale is selenium-rich and contains native selenium, V-Mo-Cr-bearing iron oxide, clay and quartz. Weathering of the selenium in the bedrock under moderate to high redox conditions in the presence of ferric iron has formed mandarinoite. 相似文献
802.
Petrology of the Non-mafic UHP Metamorphic Rocks from a Drillhole in the Southern Sulu Orogenic Belt, Eastern-Central China 总被引:9,自引:0,他引:9
ZHANG Zeming XU Zhiqin XU HuifenInstitute of Geology Chinese Academy of Geological Sciences Baiwanzhuang Rd. Beijing E-mail: zzm@ccsd.org.cn. 《《地质学报》英文版》2003,77(2):173-186
The Drillhole ZK703 with a depth of 558 m is located in the Donghai area of the southern Sulu ultrahigh-pressure (UHP) metamorphic belt, eastern China, and penetrates typical UHP eclogites and various non-mafic rocks, including peridotite, gneiss, schist and quartzite. Their protoliths include ultramafic, mafic, intermediate, intermediate-acidic, acidic igneous rocks and sediments. These rocks are intimately interlayered, which are meters to millimeters thick with sharp and nontectonic contacts, suggesting in-situ metamorphism under UHP eclogite facies conditions. The following petrologic features indicate that the non-mafic rocks have experienced early-stage UHP metamorphism together with the eclogites: (1) phengite relics in gneisses and schists contain a high content of Si, up to 3.52 p.f.u. (per formula unit), while amphibolite-facies phengites have considerably low Si content (<3.26 p.f.u.); (2) jadeite relics are found in quartzite and jadeitite; (3) various types of symplectitic coronas and pseud 相似文献
803.
HE Ying DONG Zhenxin YUE Kefen ZHANG Zhanjun WANG XinKey Laboratory of Continental Dynamics Ministry of Education Department of Geology Northwest University Xi''an Shaanxi E-mail: heying@nwu.edu.cnGeological Museum of Chin Beijing Department of Chemistry Northwest University Xi''an Shaanxi 《《地质学报》英文版》2003,77(2):212-219
We have analyzed the gold content of 65 samples of mantle-derived xenoliths and their host rocks from eastern China, which is found to be inhomogeneous, falling in the ranges of 1.0×109-8.2×109 (averaging 3.8 ×10-9) and 0.2×10-9-5.3×10-9 (averaging 2.7×10-9) in the mantle-derived xenoliths and the host basalts respectively. Except the samples from Wanquan County of Hebei Province and Anding County of Hainan Province, the gold content is the highest on the margins of the North China platform and decreases spatially towards the north and south, and temporally the samples of the Tertiary have a higher gold content than those of the Quaternary. The gold content of the mantle-derived xenoliths and the host Paleozoic kimberlites is 3.8×10-9-180×109and 0.1×10-9-38.0×10-9 respectively, which are higher than that in the mantle-derived xenoliths in basalt and the host Cenozoic basalts. The mantle-derived xenoliths have a higher gold content than the host rocks, but their relativity is not very clear, su 相似文献
804.
LING Qicong LIU CongqiangLaboratory for Study of the Earth''s Interior Geofluids Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou E-mail: lingqicong@hotmail.com China University of Geosciences Wuhan Hubei 《《地质学报》英文版》2003,77(2):246-257
REE and other trace elements in the altered marbles, massive skarns and ores, as well as garnet and quartz were determined in order to examine the behaviors of trace elements during hydrothermal alteration. It is demonstrated that the high-field-strength (HFS) elements Zr, Hf, Th and Nb were immobile while other trace elements were mobile during the formation of skarns and related deposits. REE and ore-forming elements such as Cu and Ag in hydrothermally-altered marbles and skarns were provided primarily by hydrothermal fluids. In the direction transverse of the strata, the more deeply the marbles were altered, the higher the total REE abundance and the larger the negative Eu anomalies would be. The chondrite-normalized REE patterns of skarns are similar to those of the marbles, but the former are distinguished by much higher REE contents and more remarkable negative Eu anomalies. Those patterns were apparently not inherited from the marble protolith, but were controlled by garnets, which were determine 相似文献
805.
Characteristics of Overpressure Systems and Their Significance in Hydrocarbon Accumulation in the Yinggehai and Qiongdongnan Basins, China 总被引:1,自引:0,他引:1
XIE Xinong WANG Zhenfeng LI Sitian ZHANG Minqiang YANG Jihai Faculty of Earth Resources China University of Geosciences Wuhan Hubei E-mail: xnxie@cug.edu.cn China National Offshore Oil Nanhai West Corporation Zhanjiang Guangdong 《《地质学报》英文版》2003,77(2):258-266
Overpressure systems are widely developed in the central depression and paleo-uplift in the Yinggehai and Qiongdongnan basins. They can be divided into three types according to the origin of abnormally high formation pressure in the reservoirs, i.e. the autochthonous, vertically-transmitted and laterally-transmitted types. The autochthonous overpressure system results from rapid disequilibrium sediment loading and compaction. In the allochthonous overpressure system, the increase of fluid pressure in sandstone originates from the invasion of overpressured fluid flowing vertically or laterally through the conduit units. The autochthonous overpressure system occurs in the deep-lying strata of Neogene age in the central depression of the Yinggehai and Qiongdongnan basins. The vertically transmitted overpressure system is developed in the shallow strata of Late Miocene and Pliocene ages in the diapiric zone of the central Yinggehai basin, and the laterally transmitted overpressure system occurs in the Oligo 相似文献
806.
Paleomagnetic study on the Early Triassic red beds from Jiaocheng, Shanxi Province ——Local rotation and tectonic significance 总被引:1,自引:0,他引:1
SHI Ruiping HUANG Baochun ZHU Rixiang& REN ShoumaiInstitute of Geology Geophysics Chinese Academy of Sciences Beijing China Correspondence should be addressed to Shi Ruiping 《中国科学D辑(英文版)》2004,(2)
Paleomagnetic and rock magnetic study has been conducted on the Early Triassic red beds of Liujiagou Formation from Jiaocheng, Shanxi Province. Hematite was shown as the main magnetic mineral. After eradicating an initial viscous component at room temperature to -100℃- 200℃, thermal demagnetization shows that most samples contain two remanence components, intermediate-temperature remanence component at 250℃-500℃ and high-temperature component at 500℃-680℃. The intermediate-temperature component has a negative fold test at the 95% confidence level. And the pole position of the intermediate-temperature component in geographic coordinates is correlated with the Middle Jurassic reference pole of the North China Block (NCB) within the 95% confidence, suggesting that it might be a remagnetiza-tion component acquired during the Yanshanian period. The high-temperature component contains both reversal and normal polarities with positive fold test and C-level positive reversal test at the 95% confidence lev 相似文献
807.
ZHAI Mingguo ZHU Rixiang LIU Jianming MENG Qingren HOU Quanlin HU Shengbiao LIU Wei LI Zhong ZHANG Hongfu & ZHANG HuafengKey Laboratory of Mineral Resources Institute of Geology Geophysics Chinese Academy of Sciences Beijing China Correspondence should be addressed to Zhai Mingguo 《中国科学D辑(英文版)》2004,47(2):151-159
An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and crust, a vast granitic intrusion and volcanism, and large-scale metallogenic explosion. The time range of the Mesozoic tectonic regime inversion in the eastern North China Block is one of the key issues to understand mechanism of tectonic regime inversion. Our updated results for recognizing the time range are mainly obtained from the following aspects: structural analyses along northern and southern margins of the NCB and within the NCB for revealing tectonic inversion from compression to extension and structural striking from -EW to NNE; geothermic analyses of the eastern sedimental basins for a great change of thermal history and regime; basin analysis for basin inversion from compression to extension and basin migration from -EW to NNE; petrological and geochemical studies of volcanic roc 相似文献
808.
各省、自治区、直辖市国土资源厅(国土环境资源厅、国土资源与房屋管理局、房屋土地资源管理局、规划与国土资源局): 土地整理开发规划是土地整理开发工作的主要依据,搞好土地整理开发规划,对于科学指导土地整理开发活动,合理安排土地整理开发项目,保障耕地保护目标的实现具有重要意义。近年来,各地依据土地利用规划大力推进土地整理开发工作,取得了显著成绩。为进一步加强和规范土地整理开发工作,现就制定、完善土地整理开发规划有关事项通知如下: 相似文献
809.
各省、自治区、直辖市国土资源厅(国土环境资源厅、国土资源和房屋管理局、房屋土地资源管理局、规划和国土资源局): 2002年全国土地估价师资格考试定于10月19日至20日举行,经研究,现将有关事项通知如下: 一、组织工作 2002年全国土地估价师资格考试由国土资源部组 相似文献
810.
各省、自治区、直辖市国土资源厅(国土环境资源厅、国土资源和房屋管理局、房屋土地资源管理局、规划和国土资源局): 为贯彻落实《国务院关于印发民航体制改革方案的通知》(国发[2002]6号)精神,全面推进民航体制改革,中国民用航空总局拟在民用机场管理体制改革中,对民用 相似文献