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Influence of Soil Geochemistry to the Quality of Winter Jujube in Zhanhua 被引量:1
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作者 高宗军 王敏 +1 位作者 庞绪贵 刘中业 《Agricultural Science & Technology》 CAS 2010年第9期209-212,216,共5页
[Objective] The aim was to investigate the effects of soil geochemistry on the quality of winter jujube.[Method]Based on the data of ecological geochemical survey in lower Yellow River Basin,the relevance of the geoch... [Objective] The aim was to investigate the effects of soil geochemistry on the quality of winter jujube.[Method]Based on the data of ecological geochemical survey in lower Yellow River Basin,the relevance of the geochemistry environment in top soils and the quality of winter jujubes was analyzed.[Result]Cd,Ni and other heavy metals in the soil more obviously affected the nutrition of winter jujubes.[Conclusion]B,Mn,MgO,Cd,Zn,K2O and other elements in the root soil played an important role in the enrichment of Cr and Hg of winter jujube fruit.And the absorption of heavy metals in winter jujube root could be interfered by improving fertilization method,to reduce the enrichment of harmful elements in jujube fruit. 展开更多
关键词 Zhanhua winter jujube Ecological geochemical environment Heavy metal element
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Analysis on Chemical Compositions in Chinese Wolfberry from Different Producing Areas 被引量:4
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作者 董海峰 任永丽 《Agricultural Science & Technology》 CAS 2012年第9期1870-1872,共3页
[Objective] This study aimed to conduct correspondence cluster analysis of the trace elements in Chinese wolfberry from Qinghai and Ningxia regions, and to investigate the relationship among the quality of the wolfber... [Objective] This study aimed to conduct correspondence cluster analysis of the trace elements in Chinese wolfberry from Qinghai and Ningxia regions, and to investigate the relationship among the quality of the wolfberry samples, the composition of trace elements and the sample sources. [Method] The determined contents of trace elements and ratios of zinc to copper (Zn/Cu) of wolfberry from 11 different producing areas of Qinghai and Ningxia regions were adopted to construct the raw measurement data matrix, to analyze the distribution characteristics of the trace ele- ments in wolfberry from Qinghai and Ningxia by using the corresponding cluster analysis method. [Result] The quality of wolfberry samples in 7hongning County, Zhongwei City, Pingluo County, Shizuishan City, Heicheng Town of Ningxia Hui Au-tonomous Region and Hehuang Valley, Golmud City of Qinghai Province is mainly related to the contents of Zn and Mn; Zn/Cu greatly affects the quality of Chinese wolfberry in Dulan County of Qinghai Province; Fe has great effect on the quality of Chinese wolfberry in Yinchuan City of Ningxia Hui Autonomous Region; Cu greatly affects the quality of Chinese wolfberry in Nuomuhong Village of Qinghai Province and a wolfberry research institute in Ningxia. [Conclusion] The relationship between the quality of wolfberry from different producing areas and the trace elements was investigated, which provides theoretical and practical basis for the cultivation, har- vesting, processing, and further development and utilization of Chinese wolfberry resources from different producing areas. 展开更多
关键词 Chinese wolfberry Correspondence cluster analysis Trace elements
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Elemental Composition and Geochemical Characteristics of Iron-Manganese Nodules in Main Soils of China 被引量:11
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作者 TAN Wen-Feng LIU Fan +2 位作者 LI Yong-Hua HU Hong-Qing HUANG Qiao-Yun 《Pedosphere》 SCIE CAS CSCD 2006年第1期72-81,共10页
Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and funct... Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and functions of iron-manganese nodules in soils and sediment. Compared to the corresponding soils, Mn, Ba, Cd, Co and Pb had strong accumulation, Ni had moderate accumulation, while Ca, Cu, Fe, Na, P, Sr and Zn accumulated to a minor degree in the iron-manganese nodules. In contrast, Si, Al, K, Mg and Ti were reduced in the iron-manganese nodules. The contents of Ba, Cd, Co, Cu, Ni, Pb and Zn were positively and significantly correlated with that of MnO2 in the iron-manganese nodules, while the contents of Cr, Cu, Ni, Pb and Zn were positively and significantly correlated with that of Fe2O3 in soils. Based on a principle component analysis, the elements of iron-manganese nodules were divided into four groups: 1) Mn, Ba, Cd, Co, Cu, Li, Ni, Pb and Zn that were associated with Mn oxides, 2) Fe, Cr and P that were associated with Fe oxides, 3) Si, K, and Mg that were included in the elemental composition of phyllosilicate, and 4) Ca, Na, Al and Ti that existed in todorokite, birnessite, lithiophorite and phyllosilicate. It was suggested that accumulation, mineralization and specific adsorption were involved in the formation processes of soil iron-manganese nodules. 展开更多
关键词 elemental composition geochemical characteristics iron-manganese nodule soil
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Platinum-group Elements Geochemistry of the Yangliuping Magmatic Ni-Cu-PGE Sulfide Deposit:Implications of Its Genetic Link with the Extrusive Basalts 被引量:4
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作者 ZHENGJianbin CAOZhimin +2 位作者 SONGXieyan ANWei1 LIUJi 《Journal of Ocean University of China》 SCIE CAS 2004年第1期93-98,共6页
Primitive mantle normalized Platinum group elements (PGE) concentration patterns for the Zhengziyanwo intrusion and Dashibao Formation basalts are of positive slope, similar to most of the world class magmatic Ni Cu P... Primitive mantle normalized Platinum group elements (PGE) concentration patterns for the Zhengziyanwo intrusion and Dashibao Formation basalts are of positive slope, similar to most of the world class magmatic Ni Cu PGE sulfide deposits. Characters of this intrusion and its related ores and Dashibao Formation basalts are their negative Pt anomaly and high concentration of Rh relative to Pt and Pd, facts being interpreted to be the results of crystallization and fractionation of Pt alloys and spinel phase free crystallization history for the magma, respectively. PGE parameters of the Dashibao Formation basalts are consistent with the general trend of those found for the Zhengziyanwo intrusion, and this might infer a genetic link between them. 展开更多
关键词 Magmatic Ni-Cu-PGE sulfide deposit PGE concentration pattern Pt-anomaly Yangliuping BASALT
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Multielement Analysis of Deep-Sea Sediments by Inductively Coupled Plasma Mass Spectrometry 被引量:4
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作者 XIA Ning WU Zhaohui +1 位作者 GUO Dongfa YAO De 《Journal of Ocean University of China》 SCIE CAS 2008年第2期137-144,共8页
Marine sediments were dissolved by HNO3-HF-HC104 in a sealed container at low pressure; HF was evaporated in an open container and salts were dissolved in HCl by heating, then transferred to 2% HNO3 solution. A total ... Marine sediments were dissolved by HNO3-HF-HC104 in a sealed container at low pressure; HF was evaporated in an open container and salts were dissolved in HCl by heating, then transferred to 2% HNO3 solution. A total of 45 elements, including Li, Be, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Sb, Cs, Ba, La, Ce, Pr, Nd, Sin, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Tl, Pb, Bi, Th and U, were measured by inductively coupled plasma mass spectrometry (ICP-MS). Conditions and sample experiments showed that this procedure defines a good experimental method which has the advantages of clear interference, easy operation and reliable results. The concentrations of the 45 elements could be used for resource exploration, environmental assessment and academic research. 展开更多
关键词 marine sediment DEEP-SEA geochemical analysis multielement determination ICP-MS
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High resolution records of flood deposition in the mud area off the Changjiang River mouth during the past century 被引量:3
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作者 胡刚 李安春 +3 位作者 刘健 徐刚 梅西 孔祥淮 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期909-920,共12页
This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-re... This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 21~pb dating and was sampled at 1-2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size (14.32-96.39 gm) contribution〉30%, Zr/Rb ratio〉l.5, and magnetic susceptibility〉16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods. 展开更多
关键词 high resolution grain size flood deposition mud area the Changjiang River
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Relocation of the Yellow River Estuary in 1855 AD Recorded in the Sediment Core from the Northern Yellow Sea 被引量:3
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作者 ZHOU Xin JIA Nan +2 位作者 CHENG Wenhan WANG Yuhong SUN Liguang 《Journal of Ocean University of China》 SCIE CAS 2013年第4期624-628,共5页
Relocation of the Yellow River estuary has significant impacts on not only terrestrial environment and human activities, but also sedimentary and ecological environments in coastal seas. The responses of regional geoc... Relocation of the Yellow River estuary has significant impacts on not only terrestrial environment and human activities, but also sedimentary and ecological environments in coastal seas. The responses of regional geochemical characteristics to the relocation event, however, have not been well studied. In the present study, we performed detailed geochemical elemental analyses of a sediment core from the northern Yellow Sea and studied their geochemical responses to the 1855AD relocation of the Yellow River estuary. The results show that TOC/TN, Co/A1203, Cr/A1203, Ni/A1203 and Se/A1203 ratios all decreased abruptly after 1855 AD, and similar decreases are observed in the sediments of the mud area southwest off the Cheju Island. These abrupt changes are very likely caused by the changes in source materials due to the relocation of the Yellow River estuary from the southern Yellow Sea to the Bohai Sea, which the corresponding decreasing trends caused by the changes in main source materials from those transported by the Liaohe River, the Haihe River and the Luanhe River to those by the Yellow River. Because the events have precise ages recorded in historical archives, these obvious changes in elemental geochemistry of sediments can be used to calibrate age models of related coastal sea sediments. 展开更多
关键词 relocation of the Yellow River estuary muddy sediments northern Yellow Sea elemental geochemistry
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Biogeochemistry of Nutrient Elements in the Changjiang (Yangtze River) Estuary 被引量:4
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作者 王保栋 屠建波 《Marine Science Bulletin》 CAS 2005年第2期72-79,共8页
Based on the biogeochemical studies on nutrient elements in the Changjiang estuary, the main results and recent progresses are reviewed in this paper, such as the nutrient fluxes into the sea, the mixing behaviors, th... Based on the biogeochemical studies on nutrient elements in the Changjiang estuary, the main results and recent progresses are reviewed in this paper, such as the nutrient fluxes into the sea, the mixing behaviors, the distribution characteristics and transportation as well as the biogeochemical behaviors of nutrients in the plume frontal region. The exploring directions and research emphases in the future are proposed. 展开更多
关键词 NUTRIENT BIOGEOCHEMISTRY the Changjiang estuary
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THE EFFECT OF DRAINAGE ON CHEMICALELEMENTS CONTENT OF MARSH 被引量:1
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作者 ZHANG Yun, LU Xian-guo (Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P. R. China Department of Urban and Resources Sciences, Nanjing University, Nanjing 210093, P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2001年第1期76-79,共4页
This paper takes marsh in the Sanjiang Plain as an example in order to research the effect of draining on the chemical elements in marsh. The Sanjiang Ecological Test Station of Mire and Uetland serves as the resarch ... This paper takes marsh in the Sanjiang Plain as an example in order to research the effect of draining on the chemical elements in marsh. The Sanjiang Ecological Test Station of Mire and Uetland serves as the resarch base. The authors selected soil samples in the Sanjiang Plain (the top and the end of the drain, marsh soil and degeneration marsh soil), mainly analyzed contents of main ions (HCO 3 ? , Cl?, SO 4 2? and NO 3 ? ), main heavy metals (Fe, Mn, Zn and Cu), nutritive elements (N, P, K), organic matter and pH value. By testing these samples as above, the paper initially researches the effect on chemical elements content by draining by the means of the contrast of chemical elements contents between marsh soil and degenerative marsh soil and different characteristics of marsh soil elements. Results show that a lot of chemical elements had been lost because of draining. 展开更多
关键词 DRAIN marsh degeneration chemical elements different characteristics
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Distribution of heavy metals in the topsoil of the Jining mining area 被引量:1
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作者 HAO Junliang HAN Zuozhen +2 位作者 WANG Cuizhen ZHOU Guangzhu LI Yinming 《Mining Science and Technology》 EI CAS 2010年第3期395-399,共5页
The geochemical baseline is the fundamental reference for environmental change and assessment.In this article we describe cluster and regression analyses with a normalization procedure.The elements Sc and Ag were chos... The geochemical baseline is the fundamental reference for environmental change and assessment.In this article we describe cluster and regression analyses with a normalization procedure.The elements Sc and Ag were chosen to calculate the environmental geochemical baseline.The geoaccumulation index was calculated and mapped to indicate the environmental quality of the soil.The results show that the urban areas are barely polluted with Ni and Cr but the rural areas in the southern part of the city, and the western part of the lake,are polluted with Ni,Cr,and Cu at the second level.On the other hand,the rural areas in the southern part of the city,and the western part of the lake,are polluted with As at a moderate level.The other area is polluted at the second level.An increase in As pollution occurs in a direction from northeast to southwest.The Cd pollution follows a trend similar to As,with an additional smaller contaminated area polluted at levelⅢ.The Hg pollution typical of urban areas occurs in the main and northern parts of the city.The geochemical accumulation index decreases from the city center to the periphery.The highest pollution level reaches levelⅣ,which indicates that the soil is seriously polluted with Hg.The southern part of the city and the rural areas to the west of the lake are not contaminated with Hg.Geological factors and the disturbance from human activities are both possible major factors:further research is needed to identify them. 展开更多
关键词 geochemical baseline heavy metal geoaccumulation index TOPSOIL
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Genesis of Qujiashan manganese deposit, Shaanxi Province: constraints from geological, geochemical, and carbon and oxygen isotopic evidences 被引量:3
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作者 WANG Zi-yong HAN Run-sheng +2 位作者 REN Tao WU Yong-tao LI Hu-jie 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3516-3533,共18页
The Qujiashan manganese deposit is located in the Longmen-Daba fold belt along the northern margin of the Yangtze Block. The layered ore bodies are distributed within the purple-red calcareous shale. Qujiashan is a hi... The Qujiashan manganese deposit is located in the Longmen-Daba fold belt along the northern margin of the Yangtze Block. The layered ore bodies are distributed within the purple-red calcareous shale. Qujiashan is a high-grade w(MnO)=8.92% to 18.76%) manganese deposit with low-phosphorus w(P2O5)=0.08% to 0.16%) content. It also has a low total REEs contents(with an average of 101.3×10-6), and has inconspicuous Ce(0.81 to 1.29) and Eu(1.00 to 1.25) anomalies. lg(Ce/Ce*) values are from-0.02 to 0.11. The ores have high SiO2/Al2O3 and Al/(Al + Fe + Mn) ratios. In figures of Fe–Mn–[(Ni+Cu+Co)×10] and lgU–lgTh, all samples show that hydrothermal exhalative fluids played an important role during mineralisation. The δ13CPDB and δ18OSMOW values of eight ore samples are from-20.7‰ to-8.2‰(with an average of-12.4‰) and from 14.3‰ to 18.7‰(with an average of 17.0‰), respectively. These carbon and oxygen isotopic features indicate that hydrothermal fluids derived from deep earth are participation in the metallogenic process, which is also supported by high paleo-seawater temperatures varying from 47.08 to 73.98 °C. Therefore, the geological and geochemical evidences show that the Qujiashan deposit formed from submarine exhalative hydrothermal sedimentation. 展开更多
关键词 manganese deposit element geochemistry carbon and oxygen isotopes GENESIS Qujiashan manganese deposit
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Zircon U–Pb dating and whole-rock elemental geochemistry of the Shazi anatase deposit in Qinglong,Western Guizhou,SW China 被引量:4
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作者 Jun Sun Zhao Jingyu Aiguo Nie 《Acta Geochimica》 EI CAS CSCD 2017年第2期329-338,共10页
The Shazi deposit is a large-scale anatase deposit in Qinglong, Guizhou Province. Zircon grains from this deposit yielded a zircon U–Pb age of *259 Ma, representing the formation age of the deposit's parent rocks... The Shazi deposit is a large-scale anatase deposit in Qinglong, Guizhou Province. Zircon grains from this deposit yielded a zircon U–Pb age of *259 Ma, representing the formation age of the deposit's parent rocks.This age is identical to the eruption age of the Emeishan large igneous province, indicating a synchronous magmatic event. The rare-earth-element patterns of laterite samples were similar to those of the weathered basalt sample, and sub-parallel to those of the Emeishan high-Ti basalts,implying a genetic relationship between the laterite and the basalt. The Chemical Index of Alteration values of laterite ranged from 96 to 98, suggesting a high degree of weathering. SiO_2, MgO, and alkaline metal elements decreased with increasing degree of weathering, while Al_2O_3, Fe_2O_3,and TiO_2 increased. We found the highest TiO_2 in laterite and the lowest in pillow basalts, indicating that Ti migrated from basalt to laterite.Our U–Pb dating and whole-rock elemental geochemistry analyses suggest that the Emeishan basalt is the parent rock of the Shazi anatase ore deposit.Based on our analysis, we propose a metallogenic model to explain the ore-forming process, in which the karst terrain formed by the Emeishan mantle plume and the subsequent basaltic magma eruption were the key factors in the formation the Shazi anatase ore deposit. 展开更多
关键词 Anatase deposit Zircon U-Pb - Emeishan basalt Karst terrain
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Element geochemical characteristics of a soil profile developed on dolostone in central Guizhou, southern China: implications for parent materials 被引量:5
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作者 Xingxing Cao Pan Wu Zhenxing Cao 《Acta Geochimica》 EI CAS CSCD 2016年第4期445-462,共18页
This study presents bulk chemical compositions of the Tongmuling soil profile, which developed on dolostone, and the overlying strata covering the bedrock in the central Guizhou province(southern China). The chemical ... This study presents bulk chemical compositions of the Tongmuling soil profile, which developed on dolostone, and the overlying strata covering the bedrock in the central Guizhou province(southern China). The chemical weathering characteristics of the studied profile were investigated and the inheritance relationships between the terra rossa and overlying strata were discussed. The results show that there is no remarkable variation in the major elements and weathering indices from the rock–soil interface to the topsoil, indicating that the studied profile was not typical for in situ crustal chemical weathering. The terra rossa were mainly composed of Si O_2, Al_2O_3 and Fe_2O_3. Compared with the insoluble residues and overlying strata, the terra rossa are characterized by an enrichment of Y and Cs and depletion of Ba and Sr. The subsoil shows a notable Ce negative anomaly, characterized by heavy rare earth element enrichment(L/H = 1.55–3.74), whereas the topsoil shows a positive Ce anomaly with light rare earth element enrichment(L/H = 5.93–9.14). According to Laterite-forming capacity estimates, the terra rossa could not have only been formed from acid-insoluble residues from the bedrock; Al_2O_3 versus Fe_2O_3and Nb plotted against Ta show significant positive correlations between the terra rossa and overlying strata. The Eu/Eu* versusGd_N/Yb_Nand ternary diagrams for Sc, Th, Zr, and Ta suggest that the overlying strata could also provide parent materials for the genesis of terra rossa. 展开更多
关键词 Terra rossa DOLOMITE Parent materials GUIZHOU China
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Research on the relation between the geologic environment and the trace elements of underground water in Huaibei Coalfield 被引量:1
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作者 宋晓梅 胡宝林 +1 位作者 桂和荣 陈陆望 《Journal of Coal Science & Engineering(China)》 2004年第2期42-46,共5页
Based on testing the trace elements of the four main aquifers of underground water in Huaibei Coalfield by using the ICP-MS in the University of Science and Tech- nology of China(USTC), the relation of trace elements ... Based on testing the trace elements of the four main aquifers of underground water in Huaibei Coalfield by using the ICP-MS in the University of Science and Tech- nology of China(USTC), the relation of trace elements of the four main aquifers was analyzed by using maximum correlation coefficient method. The study indicates that the different aquifers posses respective microelement distributional characteristics, which caused with average contents of trace elements in the different aquifers are related to the pH of the underground water and the contents of trace elements of the wall rock source in the research area, so researching on the distribution of geographic space and the change trend of hydro-geochemical character of different aquifers and the relation of the geologic environment and the trace elements conduce to establish the disciminand model of water inrush source. 展开更多
关键词 AQUIFER trace element geochemical characteristic CORRELATIVITY
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Zircon geochemistry of different intrusive phases of Weiya pluton: implications for magma genesis 被引量:3
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作者 张遵忠 顾连兴 +3 位作者 吴昌志 吴华 郗爱华 唐俊华 《Journal of Central South University of Technology》 EI 2005年第4期472-477,共6页
The characteristics of hosted magmas and their petrogenesis based on electron microprobe determination of trace element contents in zircons were discussed. Trace element geochemistry of zircons indicates that zircons ... The characteristics of hosted magmas and their petrogenesis based on electron microprobe determination of trace element contents in zircons were discussed. Trace element geochemistry of zircons indicates that zircons in both gabbro and quartz syenite have two-generations. Zircons of the first generations are crystallized in the magma chamber, whereas those of the second generations are formed in supercooling environment. The former is richer in Zr, but poorer in U, Th, Hf and Y. Quartz diorite porphyrite contains zircons that can be distinguished into the early and late generations. Compared to the late generation, the early generation is richer in Zr but poorer in U, Th, Hf and Y. No conspicuous disruption of zircon evolution has been found in both biotite monzogranite and fine-grained granite. However, the content of zircon in fine-grained granite is higher in U, Th and Y and lower in Zr relative to biotite monzogranite without significant contrast in mass fraction ratio of ZrO2 to HfO2 ratio. Such differences in zircon geochemistry of various intrusive phases and the occurrence of the two zircon generations within a single intrusive phase suggest that these phases of magmas are generated from diverse sources during post-collisional continental extension. These magmas ascend rapidly and cool quickly in a short interval. 展开更多
关键词 ZIRCON trace element PETROGENESIS Weiya Eastern Tianshan
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Geochemical characteristics of Galandrud coal in central Alborz, Iran 被引量:1
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作者 Ardebili Leila Babazadeh Vasef +1 位作者 Mammadov Mousa Navi Pedram 《International Journal of Mining Science and Technology》 2012年第1期101-106,共6页
This study focuses on the geochemistry of trace elements and parameters of coal quality of bituminous coal belonging to the upper Triassic-lower Jurassic era, collected from the Galandrud region in Central Alborz, nor... This study focuses on the geochemistry of trace elements and parameters of coal quality of bituminous coal belonging to the upper Triassic-lower Jurassic era, collected from the Galandrud region in Central Alborz, northern Iran. Galandrud coal on an air-dried basis are characterized by broad variation in the amount of ash (ranging from 6.49g to 12.73%), a high content of volatile matter (33,32-37.45%) and high gross calorific values (7430-8880 kcal/kg). The mineral matter of the coal samples studied is made up of dolomite (〉909g), quartz, sphalerite, galena, pyrite and clay minerals. Major elements are positively cor- related with ash content suggesting an association with inorganic constituents. Based on statistical anal- yses, concentrations of trace elements such as Co (51.3 ×10^-6-152.9× 10^-6), Ba (368× 10^-6-3297.4×10^-6), Cr (65.5 ×10^-6-194.2 × 10^-6), Mo (5.6 × 10^-6-18.2× 10^-6), Hi (72.9 × 10^-6-152.9 × 10^-6) and V (245.5 × 10^-6-520 ×10^-6) are higher than world coal averages. However, low concentration of some vol- atile elements such as As, Hg and U are present in low concentrations of the various types of coal studied. 展开更多
关键词 Galandrud coals GEOCHEMISTRY Trace elements Central Alborz lran
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Geochemical characteristics of Guizhou Permian coal measure strata and analysis of the control factors 被引量:10
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作者 YANG Rui-dong LIU Ling +2 位作者 WEI Huai-rui CUl Yu-chao CHENG Wei 《Journal of Coal Science & Engineering(China)》 2011年第1期55-68,共14页
Based on element geochemical studies of the main Permian exploitable coal measure strata in Western Guizhou, the element geochemical distribution characteristics of the main exploitable coal measures were revealed in ... Based on element geochemical studies of the main Permian exploitable coal measure strata in Western Guizhou, the element geochemical distribution characteristics of the main exploitable coal measures were revealed in the regions of Dafang, Qianxi, Weining, Hezhang, Zhijin, etc., of Guizhou Province, and the results show that their element contents are mainly affected by terrestrial material supply. Coal measures formed in the delta plain environment where sufficient terrestrial materials are supplied contain relatively abundant trace elements and rare-earth elements, whereas those formed in the tidal-fiat environment influenced greatly by seawater have relatively low contents of trace elements and rare-earth elements, mainly con- trolled by the geological fact that basalts the parent rocks from source regions contain high trace elements and rare-earth elements. In addition, coal measures affected by later hydrothermal activities and fault tectonics contain a large amount of harmful elements. According to the rules of distribution of elements in coal measures, a new idea was put forward to classify coal-forming environments by using the geochemical composition characteristics, which is of great significance in dissolving the problem of whether coal measures were fbrmed either in delta environments or in tidal-flat environments in Western Gui- zhou. At the same time, the rules of distribution of elements in the main exploitable coal measures in Western Guizhou were fully understood, which is of direct significance in utilizing coal resources on the basis of classification of coals, as well as in developing the coal chemical industry. 展开更多
关键词 element geochemistry sedimentary environment major exploitable coal measures PERMIAN Western Guizhou
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Geochemistry of Trace and Rare Earth Elements in Red Soils from the Dongting Lake Area and Its Environmental Significance 被引量:7
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作者 MAO Long-Jiang MO Duo-Wen +1 位作者 YANG Jing-Hong SHI Chen-Xi 《Pedosphere》 SCIE CAS CSCD 2009年第5期615-622,共8页
Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of China were determined to understanding the provenance and weathering characteristics of the red soils.The results show... Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of China were determined to understanding the provenance and weathering characteristics of the red soils.The results showed similar REE distribution patterns among red soils from the Dongting Lake area,Xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess Plateau.These patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of weathering.Trace element,especially the Rb/Sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering intensity.Higher Rb/Sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake area.The weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess Plateau.Variations in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity. 展开更多
关键词 Hunan Province PROVENANCE sedimentary processes weathering intensity
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^(210)Pb Chronology and Trace Metal Geochemistry in the Intertidal Sediment of Qinjiang River Estuary, China 被引量:2
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作者 XIA Peng MENG Xianwei +3 位作者 FENG Aiping YIN Ping WANG Xiangqin ZHANG Jun 《Journal of Ocean University of China》 SCIE CAS 2012年第2期165-173,共9页
Historical records of metal inputs were studied by using a sediment core collected from a sand-rich mudflat in the Qinjiang River estuary, China. 210Pb chronology was used to reconstruct the fluxes of Hg, Cu, Pb, Zn, ... Historical records of metal inputs were studied by using a sediment core collected from a sand-rich mudflat in the Qinjiang River estuary, China. 210Pb chronology was used to reconstruct the fluxes of Hg, Cu, Pb, Zn, Cd, Cr and As to the core site during the last 86 years. Based on the constant initial concentration model, the sedimentation rates are 1.18 cm year-1 in the top 30 cm sandy layer and 0.92 cm year-1 in the muddy bottom layer. To compensate for grain-size and mineralogy effects on metal concentra-tions, aluminum was used as the normalizing element. The enrichment factors (EF) indicate that the natural inputs had prevailed up to the early 1980s. After this period, the intensity of human activities has resulted in continual increasing trend of metals towards the surface. Recent sediment samples from the Qinjiang River estuary are found moderately enriched by Cd (EF>1.5) and slightly enriched by other metals (EF<1.5). Considering that the drainage area of the Qinjiang River is mostly agricultural land, the increased Cd may be due to the usage of fertilizers and pesticides in agricultural activities and the combustion of fossil fuels. 展开更多
关键词 trace metals ^210Pb chronology pollution SEDIMENTS Qinjiang River estuary
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Geochemical Characteristics of Heavy Metals in Riparian Sediment Pore Water of Songhua River, Northeast China 被引量:2
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作者 ZHU Hui YAN Baixing +2 位作者 PAN Xiaofen YANG Yuhong WANG Lixia 《Chinese Geographical Science》 SCIE CSCD 2011年第2期195-203,共9页
This study reports the geochemical characteristics of zinc (Zn), copper (Cu), lead (Pb), nickel (Ni), mercury (Hg), iron (Fe), and manganese (Mn) in the riparian sediment pore water of the Songhua River, Northeast Chi... This study reports the geochemical characteristics of zinc (Zn), copper (Cu), lead (Pb), nickel (Ni), mercury (Hg), iron (Fe), and manganese (Mn) in the riparian sediment pore water of the Songhua River, Northeast China. In total, 36 pore water samples and 18 surface water samples from three typical sections were collected and analyzed in June 2009. Cluster analysis of heavy metals was performed to analyze the pollution sources of the metals. Results showed that Hg concentrations in the pore water were greater than those in the surface water, indicating a potential ability of Hg release from riparian sediment system to river water. However, concentrations of Fe and Mn in the surface water were greater than those in the pore water, demonstrating that the microenvironments of riparian and riverbed sediment systems were quite different. Variations of Zn, Cu, Pb and Ni between the surface and the pore water were different in each section. Most metals had similar horizontal and profile distribution characteristics in the three sections except for Zn and Ni. Hg, Fe and Mn concentrations in the pore water increased gradually with the increase in horizontal distance from water body, in contrast to this, Cu decreased, and Pb presented a fluctuating trend. With the increase in depth, Pb and Fe, Cu and Mn showed the same trends, and Hg showed a variable trend. The above distribution characteristics could mainly be attributed to the properties and the interactions of metals, pH and oxidation-reduction conditions, and the complex pollution sources and hydrologic regime in history. The probable sources of metals include the historical and ongoing discharge of industrial wastewater, mining activities, sewage irrigation for agricultural production, and atmospheric deposition from coal-fired plants. 展开更多
关键词 heavy metal riparian sediment pore water water pollution Songhua River
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