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131.
HU Kai YU Chensheng MA Dongsheng ZHAI Jianping ZHANG WenlanDepartment of Earth Sciences Nanjing University State Key Laboratoryfor Mineral Deposit Research Nanjing University Nanjing XIAO Zhenyu Guangdong Nonferrous Metals Geological Exploration Bureau Guangzhou Zhang Yuxu Zhu Xiling 《《地质学报》英文版》2002,76(2):249-256
The silver contents of organic matter in the host rocks of the Songxi shale-hosted Ag-Sb deposit of northeastern Guangdong, South China, have been directly determined using the electron microprobe technique. The silver contents in two types of organic matter, marine vitrinite and solid bitumen, vary in the range from 100×10-6to 350×10-6, which are from tens of times to thousands of times higher than those of the host rocks in the ore deposit. The average silver content of the organic matter is also several times higher than the pay grade of silver for commercial mining of the ore deposit. It is quite obvious that the organic matter of the host rocks in the ore district is characterized by an anomalous enrichment of silver. The results of this study indicate that the silver anomalies in the organic matter have been derived from both the host rocks and the silver-bearing fluids of the Songxi black shale ore source. In the course of sedimentation and later hydrothermal reworking, organic matter was able 相似文献
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随着现代小卫星技术的不断发展成熟,利用该技术为地球观测服务将成为一件远景可观,意义深元的事情,文中针对舆型航天遥感立体测绘微小卫星的需求,结合单脉冲测角原理给出了航天遥感测绘小卫星地面站面线系统的整体分析与设计。 相似文献
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ZHI Xiachen CHEN Peng LIN Chengzhong CHEN Shuqing ZHANG Guilan LI Yuzhi LIN Lei 《《地质学报》英文版》2001,75(1):51-58
The Mössbauer spectra of natural megacrystal clinopyroxene are usually fitted by 4 sets of symmetric doublets, A‐A', B‐B', C‐C' and D‐D', respectively, in terms of increasing Qs value in literature. But the assignments of those doublets are quite different, except the D‐D' doublet assigned to Fe3+at the lattice site M***1 in previous papers. Particularly, the assignment and interpretation of the C‐C' doublet are diverse. The oxidation experiments of natural megacrystal clinopyroxene collected from the Hannuoba basalt, North China, were performed under controlled conditions of temperature at 1000°C and oxygen fugacity of FMQ buffer in 1, 2, ***3 and 5 days respectively. The oxidized samples were then measured by X‐ray diffraction spectrometry and Mössbauer spectrometry. The oxidation of clinopyroxene is characterized by Fe2+ → Fe3+at M1 under the subsolidus conditions, which is consistent with the increase of the area of the D‐D' doublet when the heating time increases. Accordingly, the area of the A‐A' and B‐B' doublets decreases with the increasing heating time. However, the area of C‐C' keeps almost constant. Therefore, the 4 sets of doublets can be assigned correctly as follows: A‐A' doublet to Fe+2at M1, B‐B' Fe2+at M1, C‐C' Fe2+at M2, and D‐D' Fe3+at M1. The M1 site splitting is due to the NNN (Next Nearest Neighbour) effect of the M2 site. The amount of Fe3+at the tetrohedral site of megacrystal clinopyroxene is negligible according to this study. 相似文献
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