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11.
12.
Taoze LIU Yuangen YANG Bangyu LIU Xiangyang BI Feili LI 《中国地球化学学报》2006,25(B08):41-42
It has been found that stream waters were severely contaminated with wastes from a long-time smelting factory in Hezhang, Guizhou, China. The main sources of contamination are the smelting wastes stored in the open air and abandoned in the vicinity of stream. A method of lead isotope was adopted in order to identify relations between tailings and water contamination. Representative samples of tailings and stream sediments were collected. Mineralogical characterizations were conducted using XRD and TEM/SEM, while acid digestion was carried out for determining metal contents. BCR sequential leaching tests were performed in order to assess metal mobility. The tremendous ‘actual' and ‘potential' mobility of heavy metals indicates that the smelting waste and stream sediments present a considerable threat to the environment. Besides the chemical remobilization of heavy metals from the sediments and the reworking of riverbed sediments act as a secondary source of pollution. Also groundwater and stream water were sampled in specific locations and were measured. 相似文献
13.
Chunye LIN Mengchang HE Baixing YAN Xiangchun QUAN Yuxiang ZHOU Wei GUO Zhifeng YANG 《中国地球化学学报》2006,25(B08):118-119
The Second Songhua River was subjected to a large amount of untreated effluent from petrochemical industries in Jilin City in the 1960s to the 1970s. The objectives of this study were to investigate the mercury and other heavy metal contamination in the sediment of the river. The river bottom sediment was sampled from the river segment between Jilin City to Haerbin City in 2005. Total concentrations of Hg, Cd, Cu, Cr, Pb, Zn, Ni, As, Sc, and major cations (A1, Fe, Mg, Ca, K, Na) in the sediment were measured by atomic fluorescence spectrometer, ICP-MS, and ICP-OES, respectively, following digestion with various acids. We found the concentrations of most elements in the uncontaminated sediment were significantly correlated to those of Sc. 相似文献
14.
Fan YANG Qinghui HUANG Jianhua LI Xiaomin ZHU 《中国地球化学学报》2006,25(B08):262-262
Dissolved organic matter (DOM) is an important chemical component in natural water. Chromophoric dissolved organic matter (CDOM), a fraction of optical properties, plays art important role in the biogeochemical cycle of nutrients in aquatic environment. People realized that DOM cycle is crucial in the global carbon and nitrogen flux, and also is inherently related to nutrients and trace metal elements. Therefore, CDOM was concerned by scientists in global oceanography and limnology fields. Water samples were collected from three sections (North Channel, South Channel and Zhuyuan) of the Yangtze (Changjiang River) estuary in March 2006 Three-dimensional excitation emission matrix (3-DEEM) fluorescence spectra were analyzed for those filtrates through Whatman GF/F filters. Dissolved organic carbon (DOC) was also measured by TOC analyzer. The tidal variety was also taken into account. The 3-D EEM fluorescence scans suggested the fluorescence characteristics of humic acid (Ex=332-344 nm, Em=439-451 nm) and fulvic acid (Ex=250-254 nm, Em=472-478 nm) were obvious, and the fluorescence group of protein-like and tyrosine (Ex=230 nm, Em=283 nm) was also found. They are mainly composed of CDOM in the Yangtze estuary. Further data analysis, especially the fluorescence index (f 450/500), showed that terrestrial signal was rather strong (1.41-1.65) in the surface water, however, some terrestrial CDOM signals of bottom water showed excursions (1.28-1.39). On the other hand, anthropogenic sign was impressed in the waters of Zhuyuan, which is one of the main drain outlets of Shanghai Metropolis. DOC concentrations ranged from 2.2 mg/L to 3.4 mg/L in Zhuyuan and South Channel, and from 2.0 mg/L to 2.4 mg/L in North Channel. The tide effect played a role in the composition of the CDOM measured by 3-D fluorescence scan technology. 相似文献
15.
同位素水文学与水资源、水环境 总被引:11,自引:0,他引:11
同位素水文学 (isotopehydrology)是 2 0世纪 5 0年代发展起来的一门新兴学科 ,它主要利用同位素技术解决水文学中一些关键问题 .众所周知 ,同位素是指原子核内质子数相同中子数不同的那些原子 ,可分为稳定同位素和放射性同位素 2种 .前者指目前尚未发现存在放射性衰变的同位素 ,而后者则指具有放射性衰变的同位素 .存在于自然界的上述 2种同位素称为天然同位素或环境同位素 ,目前在水文学中常用的环境同位素有2 H、3 H、3 He、4He、13 C、14C、18O、3 4 S、3 6Cl等 .不同类型的水 (海水、湖水、河水、地下水 ,… 相似文献
16.
1 INTRODUCTION There were many flood disasters in China in recent years. When the water level in a river is very high, weak parts of its dike may be destroyed resulted in the submersion of the protected land and properties. It is of significance for decision-makers to exactly predict the processes of flood propagation during flood control. There are many modes of dike bursting, such as seepage destroying by overflow on top of dike caused by dike body sinking induced by piping and soil fl… 相似文献
17.
~(40)Ar/~(39)Ar Dating of Deformation Events and Reconstruction of Exhumation of Ultrahigh-Pressure Metamorphic Rocks in Donghai, East China 总被引:3,自引:0,他引:3
LI Jinyi YANG Tiannan CHEN Wen ZHANG Sihong Institute of Geology Chinese Academy of Geological Sciences Beijing E-mail: jyli@cags.net.cn 《《地质学报》英文版》2003,77(2)
Recent investigations reveal that the ultrahigh-pressure metamorphic (UHPM) rocks in the Donghai region of East China underwent ductile and transitional ductile-brittle structural events during their exhumation. The earlier ductile deformation took place under the condition of amphibolite facies and the later transitional ductile-brittle deformation under the condition of greenschist facies. The hanging walls moved southeastward during both of these two events. The 40Ar/39Ar dating of muscovites from muscovite-plagioclase schists in the Haizhou phosphorous mine, which are structurally overlain by UHPM rocks, yields a plateau age of 218.0±2.9 Ma and isochron age of 219.8Ma, indicating that the earlier event of the ampibolite-facies deformation probably took place about 220 Ma ago. The 40Ar/39Ar dating of oriented amphiboles parallel to the movement direction of the hanging wall on a decollement plane yields a plateau age of 213.1±0.3 Ma and isochron age of 213.4±4.1 Ma, probably representing the age o 相似文献
18.
Re-Os Age of Cu-Ni Ores from the Huangshandong Cu-Ni Sulfide Deposit in the East Tianshan Mountains and Its Implication for Geodynamic Processes 总被引:4,自引:0,他引:4
MAO Jingwen YANG Jianmin QU Wenjun DU Andao WANG Zhiliang HAN Chunming Faculty of Geosciences Resources China University of Geosciences Beijing E-mail: jingwenmao@.netInstitute of Mineral Resources Chinese Academy of Geological Sciences Beijing National Research Center of Geoanalysis Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》2003,77(2):220-226
An isochron age of 282±20 (95% conf. limit) Ma of the sulfide ores in the Huangshandong Cu-Ni sulfide deposit, the East Tianshan Mountains has been obtained through Re-Os isotopic measurement. The age implies that the Cu-Ni sulfide deposit and other related deposits in the same area occurred in a Permian extensional environment of post-collision instead of Devonian-Early Carboniferous ophiolite-related oceanic or island arc environments inferred before. It shares the same ages with the orogenic and epithermal gold deposit systems in the same area. An initial 187Os/188Os ratio of 0.25±0.04 (1σ) and a γos value of 99 on average display the participation of large quantities of crustal components into the rock-forming and ore-forming system during mineralization and magmatic emplacement. 相似文献
19.
SHI Nicheng BAI Wenji MA Zhesheng FANG Qingsong XIONG Ming YAN Binggang DAI Mingquan YANG JingsuiChina University of Geosciences Beijing E-mail: shinicheng@a-l.net.cn Institute of Geology Chinese Academy of Geological Sciences Beijing Liu Shuchun Zhu Xiling 《《地质学报》英文版》2003,77(3):326-331
Diamond was found in podiform chromitites of ophiolite and harzburgite from Luobusha, Tibet. There are silicate inclusions in some diamond grains from this area. In the present work, the CCD (charge coupled detector) technology of X-ray powder diffraction was applied to the study of the inclusion in diamond from the ophiolite of Tibet. Diffraction patterns are obtained even though the inclusion is only 20 μm in crystal size. The results show that the inclusion in diamond consists of talc and clinochrysotile. Therefore, it is clear that the diamond from the ophiolite of Luobusha, Tibet, is natural diamond rather than a synthetic one. 相似文献
20.
DENG Jun YANG Liqiang SUN Zhongshi WANG Jianping WANG QingfeiXIN Hongbo LI Xinjun Key Laboratory of Lithospheric Tectonics Exploration. China University of Geosciences Ministry of Education Beijing Institute of Geology Geophysics Chinese Academy of Sciences Beijing Faculty of Earth Sciences Jilin University Changchun Jilin 《《地质学报》英文版》2003,77(4):537-546
An analysis of trace elements and isotopic geochemistry suggest that the ore-forming materials of gold deposits in the Jiaodong granite-greenstone belt have multiple sources, especially the mantle source. Seismic wave, magnetic and gravity fields show that the crust-mantle structure and its coupling mechanism are the fundamental dynamic causes for the exchange and accumulation of materials and energy in the metallogenic system. Considering the evolution history of the structural setting, the tectono-metallogenic dynamics model of the area can be summarized as follows: (1) occurrence of the greenstone belt during the Archean-Proterozoic-the embryonic form of Au-source system; (2) stable tectonic setting in the Paleozoic-an intermittence in gold mineralization; (3) intensive activation and reformation of the greenstone belt in the Mesozoic-tectono-mineralization and tectono-diagensis; (4) posthumous structural activity in the Cenozoic-destruction of orebodies in the later stage. In the middle and late Ind 相似文献