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New Data on Coal, Gypsum, Iron and Silica Sand Deposits and Geochemical Exploration (Pakistan): Revision of 25 Years History of Dinosaur Discoveries from Pakistan
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作者 Muhammad Sadiq Malkani 《Open Journal of Geology》 CAS 2024年第3期431-511,共81页
Discoveries of many coal seams at depths by drilling carried by Geological Survey of Pakistan in Sor Range and Harnai Gochina, extended the coal seams at depth which is challenge for mine owners to exploit feasibly. B... Discoveries of many coal seams at depths by drilling carried by Geological Survey of Pakistan in Sor Range and Harnai Gochina, extended the coal seams at depth which is challenge for mine owners to exploit feasibly. Bed to bed gypsum samplings (and their chemical analyses) of huge gypsum deposits from Sulaiman foldbelt is a base for industrialist and also planers to develop cement and gypsum industries to increase export and foreign exchange for the development of area and Pakistan. Low and high grade sedimentary iron deposits, silica sand and uranium host rocks and their extensions in Sulaiman and Kirthar foldbelts are presented. Anomalies of a few base metals arise as a result of geochemical exploration carried at part of Loralai District of Balochistan. Theropod dinosaurs were frequent in India, while Poripuchian titanosaurs (Sauropoda, Dinosauria) were frequent in Pakistan. Besides some ichnotaxa, many bone taxa such as 1 titanosauriform, 14 titanosaurian sauropod (including one new titanosaur), and 3 theropod dinosaurs are established from Pakistan. Among these 12 titanosaur species and 3 theropod species are named in about 10 km<sup>2</sup> area of Vitakri dome and 2 titanosaur species are named in about a few hundred square meter area of Mari Bohri (Kachi Bohri) which is about 10 km westward from Vitakri dome. Pakistan is a unique country which discoverd 14 diversified titanosaurs in a short area and also in a short period (67 - 66 million years ago/Ma). About 400 bones found from a few meter thick upper part of upper shale horizon of latest Maastrichtian Vitakri Formation which is base for titanosaur taxa. Cranial material is in low fraction (but include significant diverse snouts), caudal vertebrae are prominent, the cervicals, dorsals and sacrals have significant numbers, forelimb and hind limb bones have balanced fraction. Humeri, femora and tibiae are most common. To know the position of Pakistani titanosaurs among titanosaurs and sauropods, there is a need to extend list of characters for phylogenetic analyses. This broad feature list should include main characters of titanosaurs from Pakistan and also from global world. 展开更多
关键词 COAL GYPSUM IRONSTONE Silica sands geochemical exploration Dinosaurs TITANOSAURIFORMES Titanosaurs Theropods REVISION BALOCHISTAN Pakistan
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Application of Wavelet Analysis toInterference Elimination for Geochemical Hydrocarbon Exploration 被引量:7
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作者 Zhang Liuping Ruan Tianjian Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 2000年第1期91-93,共3页
Interference in the data of geochemical hydrocarbon exploration is a large obstacle for anomaly recognition. The multiresolution analysis of wavelet analysis can extract the information at different scales so as to pr... Interference in the data of geochemical hydrocarbon exploration is a large obstacle for anomaly recognition. The multiresolution analysis of wavelet analysis can extract the information at different scales so as to provide a powerful tool for information analysis and processing. Based on the analysis of the geometric nature of hydrocarbon anomalies and background, Mallat wavelet and symmetric border treatment are selected and data pre-processing (logarithm-normalization) is established. This approach provide good results in Shandong and Inner Mongolia, China. It is demonstrated that this approach overcome the disadvantage of backgound variation in the window (interference in window), used in moving average, frame filtering and spatial and scaling modeling methods. 展开更多
关键词 geochemical exploration petroleum exploration interference elimination wavelet analysis data processing anomaly recognition.
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A Study of the Method for the Recognition of Anomalies in Geochemical Hydrocarbon Exploration 被引量:2
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作者 Zhang Liuping Doctoral Student, China University of Geosciences, Wuhan 430074 Liao Zebin North China Institute of Petroleum Exploration and Development, Renqiu 062552 《Journal of Earth Science》 SCIE CAS CSCD 1998年第1期74-82,共9页
The greatest difficulties in recognizing geochemical hydrocarbon anomalies are: (1) how to objectively and accurately separate anomalies from background; (2) how to distinguish hydrocarbon pool related apical anomal... The greatest difficulties in recognizing geochemical hydrocarbon anomalies are: (1) how to objectively and accurately separate anomalies from background; (2) how to distinguish hydrocarbon pool related apical anomalies from lateral anomalies controlled by faults; and (3) how to eliminate interferences. These uncertainties are serious obstacles for the wide acceptance and use of geochemical techniques in hydrocarbon exploration. In this paper, the features of hydrocarbon anomalies were analyzed based on the micro migration mechanisms. In most cases, there are two anomalous populations or point groups, which are produced by two distinct mechanisms: (1) a population that directly reflects oil and gas fields, and (2) one that is related to structures such as faults. Statistical studies show that background anomalous populations and the boundaries between them can be described by the population means, prior probabilities, which are the proportions of population sizes, and covariance matrices, when background and anomalous populations have normal distributions. When this normality condition is met, a series of formulas can be derived. The method is designed on the basis of these allows: (1) univariate anomaly recognition, (2) elimination of interferences, (3) multivariate anomaly recognition, and (4) multivariate anomaly combination which depicts a more representative picture of morphology of the anomalous target than individual anomalies. The univariate and multivariate anomaly recognition can not only separate anomalies from background objectively, but also simultaneously distinguish the two types of anomalies objectively. This method was applied to the hydrocarbon data in Yangshuiwu region, Hebei Province. The interferences from regional variation of background were eliminated, and the interpretation uncertainty was reduced greatly as the anomalous populations were separated. The method was also used in Daxing region within the confines of Beijing City, and Aershan and Jiergalangtu regions in Inner Mongolia. 展开更多
关键词 geochemical exploration petroleum exploration ANOMALY RECOGNITION data processing method research.
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Geochemical and Geophysical Data Processing Aided by“Multifractal-Spectrum”Filters for GIS-Based Mineral Exploration 被引量:2
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作者 Xu Yaguang Cheng Qiuming Department of Earth and Atmospheric Science, York University, North York, Ontario, M3j 1P3 Canada 《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期36-38,共3页
A recently developed method, on the bases of “multifractal spectrum” filters for mineral exploration, is introduced in this paper. The “multifractal spectrum” filters, a group of irregularly shaped filters that a... A recently developed method, on the bases of “multifractal spectrum” filters for mineral exploration, is introduced in this paper. The “multifractal spectrum” filters, a group of irregularly shaped filters that are constructed on each processed datum, can be used to separate various types of geochemical and geophysical anomalies. The basic model, with an emphasis on the GIS based implementation and the application to the geochemical and geophysical data processing for mineral exploration in southern Nova Scotia, Canada, indicates its advantage in the separation of multiple anomalies from the background. 展开更多
关键词 multifractal spectrum GIS based mineral exploration geochemical and geophysical anomalies.
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Application of Lead Isotopes to Geochemical Exploration of Gold Deposits in Baoban,Hainan Province, China 被引量:3
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作者 常向阳 朱炳泉 +1 位作者 俞受鋆 夏萍 《Chinese Journal Of Geochemistry》 EI CAS 2003年第3期244-252,共9页
Lead isotopes have been widely applied in geochemical explora tion and evaluation of ore deposits, as well as in ascertaining the age of miner alization and the source of ore fluids. Long-term practice showed that the... Lead isotopes have been widely applied in geochemical explora tion and evaluation of ore deposits, as well as in ascertaining the age of miner alization and the source of ore fluids. Long-term practice showed that the meth od of lead isotope targeting is somewhat efficient for macroscopic evaluation of forecasting areas, but not powerful enough for forecasting concealed orebodies. As the contents of U and the variation of U/Pb ratio sharply decrease with dept h in the lithosphere, U-Th-Pb isotopic differentiation must have occurred duri ng the crust-mantle evolution. Lead isotopic ratios show a wide variation range , varying in the front of mineralization and shallow-derived ores, but maintain ing very stable in the major orebody and being usually close to the average isot opic composition of the crust and mantle of the continent block from which the o res were derived. Therefore, the lead isotopic composition can serve as a measur e for identifying the position of mineralization. The lead isotope geochemistry was applied to the exploration and evaluation of the Baoban gold deposits of Hai nan Province, China. The analytical results of ore veins and adjacent rocks show ed that there is a correlation between the lead isotope data and the position of orebody. Based on the experience from the Baoban gold deposits and other ore de posits in Yunnan Province, an exploration principle has been established, that i s, positive anomalies of lead isotope eigenvectors for prospecting deep-seated orebodies and negative anomalies of eigenvectors for enlarging lateral explorati on surrounding the known deposit. The ore beds in the Erjia and Beiniu mining di stricts should be assigned to the deep part of the orebody and those in the Tuwa ishan mining district should be the shallow part, so ore beds corresponding to t hose in the Erjia and Beiniu mining districts may be found in the Tuwaishan mini ng district. 展开更多
关键词 铅同位素 地球化学探测 金矿床 海南
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Important Achievement and Advance of Natural Gas Geology and Geochemical Exploration in China 被引量:3
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作者 SUN Yuzhuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1411-1411,共1页
Academician Dai Jinxing has long been engaged in natural gas geology and geochemical researches,and has made prominent contributions to the establishment and development of China’s theory of coal-derived gas.He has o... Academician Dai Jinxing has long been engaged in natural gas geology and geochemical researches,and has made prominent contributions to the establishment and development of China’s theory of coal-derived gas.He has opened up new areas of coal-derived gas exploration,natural gas formation theory and formation“ control conditions of large ” medium gas fields. 展开更多
关键词 Important Achievement and Advance of Natural Gas Geology and geochemical exploration in China
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Application of Tectono Geochemical Study in Deep Concealed Ore Body Exploration--As the Huize Super-Large Lead-Zinc Deposit an exemple 被引量:1
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作者 ZHANG Quan GUO Yuxinyue +1 位作者 PU Chuanjie WANG Feng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期247-248,共2页
1 Geological Background of Minerlization or Geologic Setting The northeast of Yunnan1 Pb-Zn-Ag-Ge polymetallic ore district is an important part of the southwestern margin of the Yangtze block Sichuan-Yunnan-Guizhou
关键词 Application of Tectono geochemical Study in Deep Concealed Ore Body exploration NE As the Huize Super-Large Lead-Zinc Deposit an exemple MVT
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Unconventional Geochemical Exploration for Gold Deposits
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作者 Wang Xueqiu and Xie Xuejin Institute of Geophysical and Geochemical Exploration, Langfang, Hebei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第3期317-329,共13页
Conventional geochemical exploration for gold deposits has not always been very satisfactory, especially for buried and blind ones. New considerations and methodology in sampling, analysis and interpretation have been... Conventional geochemical exploration for gold deposits has not always been very satisfactory, especially for buried and blind ones. New considerations and methodology in sampling, analysis and interpretation have been developed in China during the past decade. Important considerations for unconventional gold exploration in this paper are that (1) gold is active in surface environments; (2) gold occurs not only as discrete grains, but also as ultrafine particles (submicron?to nanometer-sized particles of gold) and other complex forms; (3) regional low anomalies and superimposed anomalies over buried gold deposits are produced by ultrafine gold grains and other complex forms of gold. The methodology based on these considerations has been developed both in regional and in local geochemical exploration for gold. Examples of the preliminary application of these methods in two areas covered by transported overburden are given. 展开更多
关键词 unconventional geochemical exploration for gold deposits theory and method APPLICATION
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New Progress in High-Precision and High-Resolution Seismic Exploration Technique in Coal Industry of China
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作者 Ni Bin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期311-315,共5页
In the past twenty years, the proportion of coal in primary-energy consumption in China is generally between 71.3% and 76.5%. The output of coal was 1.374 billion tons in 1996, and 1.21 tons in 1998, which ranked firs... In the past twenty years, the proportion of coal in primary-energy consumption in China is generally between 71.3% and 76.5%. The output of coal was 1.374 billion tons in 1996, and 1.21 tons in 1998, which ranked first in the world. Now coal is mined mainly with mechanization in China, which is planned to reach 80% in major State-owned coal mines in 2000 according to the planning of the government (Li et al., 1998; Tang Dejin, 1998). 展开更多
关键词 COAL high-precision seismic exploration technique PROGRESS
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Geochemical Exploration for Gold and the Association of As-Cu-Pb-Sn-Zn-Li in the Upper Proterozoic Granitoids of the Wadi Rumman Area, Southwest Jordan
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作者 I.A.A. Bany Yaseen 《International Journal of Geosciences》 2015年第10期1140-1153,共14页
The geochemical studies were conducted in an area covering about 15 km2?of the south side of the Wadi Rumman area, SW Jordan. The study area included a part of a basement of complex exposed rocks in southwestern Jorda... The geochemical studies were conducted in an area covering about 15 km2?of the south side of the Wadi Rumman area, SW Jordan. The study area included a part of a basement of complex exposed rocks in southwestern Jordan. The complexes comprised igneous and metamorphic suites, mostly from the late Proterozoic age. A systematic geochemical sampling was conducted using rock and heavy mineral-panned concentrate of geochemical samples. Fifty rock samples were collected from the granitic rocks, simple pegmatite dyke, quartz veins and alteration zone, which covered the area. Next, 45 heavy mineral-panned concentrate samples were collected from the alluvium in the stream sediment within the catchment area, and the dray was sieved to less than 1 mm grain size. The geochemical samples were analyzed for their trace elements and gold by using Ione Conductive Coupled Plasma Emission Spectroscopy (ICP-AES) and the Atomic Absorption Spectrometer (AAS) at Natural Resources Authority (NRA) Labs. The results of the geochemical analysis indicated the presence of gold and heavy minerals in the study area, a result considered abnormal in the rock samples. A strong positive correlation was recorded of Au with As, Cu and W (r =?0.82, 0.7 and 1.0), as with Mo (r = 0.83), Cu with Pb (r = 0.83), Sn with Mo (r = 0.73), Mo with W (r = 0.97), Zn with W (r = 0.71), and Li with Bi (r = 0.7). These correlations revealed gold associated within the hydrothermal alteration, quartz veins and pegmatite dyke. Abnormal metals such as As and Bi were good path-finders to find Au. The HM samples showed low positive linear correlations among the concentrations of Au with As, Zn and Li, and negative linear correlations of Au with Pb, Sn, Bi and W. The combination of both rock and heavy mineral concentrate samples shows four geochemical anomalous areas of gold and heavy minerals. The geochemical signatures of Au and As in the Wadi Rumman appear to be in the hydrothermal alteration, quartz veins and pegmatite dyke, respectively. Heavy mineral concentration sampling delineated the Au geochemical anomaly in area 1 specificities with the rock geochemical anomaly of area 1. 展开更多
关键词 geochemical exploration GRANITOIDS Rock and Heavy Mineral Samples WADI Rumman JORDAN
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Geochemistry of Termite Hills as a Tool for Geochemical Exploration of Glass Sand in the Iraqi Western Desert
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作者 Salih Muhammad Awadh 《International Journal of Geosciences》 2010年第3期130-138,共9页
Sand glass deposits was located in the mid of the Western Desert of Iraq. It is situated within Rutba Formation (Ceno-manian). Ancient traditional mining method is still used in exploitation the unconsolidated white g... Sand glass deposits was located in the mid of the Western Desert of Iraq. It is situated within Rutba Formation (Ceno-manian). Ancient traditional mining method is still used in exploitation the unconsolidated white glass sand from glass sand quarry. The overburden thickness ranges from 2 to 4 m in average. Termite hills were observed around the glass sand quarry extending far from the quarry area. Termites could burrows down and penetrate the sand glass bringing it up to the surface. The depth of penetration reaches more than 35 m. The field observation of the white color of termite hills which are built up by sand glass gave a good indicator for the hidden subsurface deposit and it appears to be a surface signature for finding glass sand directly under the termite hills. The scattered white hills of glass sand on the surface with high content of SiO2, concordant Zr/Hf and Th/U ratios and heavy mineral distribution in both of quarry and termite hills provide a strong evidence of that those termite hills could be an effective tool for exploring subsurface hidden glass sand up to 35 m depth. 展开更多
关键词 geochemISTRY Glass SAND geochemical exploration TERMITE Hill IRAQI WESTERN DESERT
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Research and Application of New Methods to Oil-Gas Geochemical Exploration
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作者 CHEN Yuanrong JIA Guoxiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期692-696,共5页
Based on the results of researches and applications for many years, it has been discovered that new methods and techniques for geochemical exploration of oil and gas such as δC, altered carbonate, Hg in absorption ph... Based on the results of researches and applications for many years, it has been discovered that new methods and techniques for geochemical exploration of oil and gas such as δC, altered carbonate, Hg in absorption phase, Ks, Fe2+, δ13C, fluorescence in two and three dimensions, and N2 and O2 in heat release can give full play in the following five fields: (1) optimization of the favourable target or hollow zones and structural zones in a region; (2) evaluation of oil traps and delineation of prospective oil and gas areas; (3) prediction of deep-seated oil-bearing horizons; (4) evaluation of the genesis of oil and gas geochemical anomalies and determination of the types of oil and gas accumulations; (5) forecast of the burial depths of oil and gas pools. 展开更多
关键词 geochemical exploration for oil and gas new method field of application
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Geochemical Orientation Study of Stream Sediment Samples in the Southern Part of Nuggihalli Schist Belt: Ore Mineral Phases and Their Implications on the Bedrock Potential for Ores
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作者 B. G. Dayanand S. Santhosh B. C. Prabhakar 《Open Journal of Geology》 2023年第8期806-827,共22页
Stream sediment sampling is a significant tool in geochemical exploration. The stream sediment composition reflects the bedrock geology, overburden cover, and metalliferous mineralization. This research article focuse... Stream sediment sampling is a significant tool in geochemical exploration. The stream sediment composition reflects the bedrock geology, overburden cover, and metalliferous mineralization. This research article focuses on assessing selected trace element concentrations in stream sediments and interpreting their inter-element relationships using multivariate statistical methods. Tagadur Ranganathaswamy Gudda and its surroundings in the Nuggihalli schist belt of southern India have been investigated in the present work. The geology of the study area is complex, with a diverse range of litho units and evidence of strong structural deformation. The area is known for its mineralization potential for chromite, vanadiferous titanomagnetite, and sulfides. The topography of the region is characterized by an undulating terrain with a radial drainage pattern. Most part of the schist belt is soil covered except the Tagadur Ranganathaswamy Gudda area. For this study, a discrete stream sediment sampling method was adopted to collect the samples. Stream sediment samples were collected using a discrete sampling method and analyzed for trace elements using an ICP-AES spectrophotometer: Fe, Cr, Ti, V, Cu, Ni, Zn, Pb, Mn, Cd, and As have been analyzed. The analytical data were statistically treated using the SPSS software, including descriptive statistics, normalization of data using natural log transformation, and factor analysis with varimax rotation. The transformed data showed a log-normal distribution, indicating the presence of geochemical anomalies. The results of the study provide valuable insights into the geochemical processes and mineralization potential of the study area. The statistical analysis helps in understanding the inter-element relationships and identifying element groups and their implications on bedrock potential mineralization. Additionally, spatial analysis using inverse distance weighting interpolation provides information about the distribution of geochemical parameters across the study area. Overall, this research contributes to the understanding of stream sediment geochemistry and its application in mineral exploration. The findings have implications for future exploration efforts and can aid in the identification of potential ore deposits in the Nuggihalli schist belt and similar geological settings. 展开更多
关键词 geochemical exploration Stream Sediment Sediment Sampling Heavy Mineral Concentrates Nuggihalli Schist Belt Dharwar Craton
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Surface geochemical anomaly pattern of medium-to-high temperature geothermal systems in South China and its application
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作者 Guangzhi Li Guojian Wang +1 位作者 Bin Hu Lirong Ning 《Energy Geoscience》 2023年第4期139-148,共10页
The existence of thermal storage will correspondingly increase the temperature of surrounding strata and promote the continuous expansion,volatilization,upward migration,and loss of gas in the strata.As a result,a low... The existence of thermal storage will correspondingly increase the temperature of surrounding strata and promote the continuous expansion,volatilization,upward migration,and loss of gas in the strata.As a result,a low-concentration gas field will be formed in the strata above geothermal reservoirs.Geothermal reservoirs could in turn heat formation water and increase the solubility of soluble inorganic salts in the surrounding rocks and the total dissolved solids(TDS)content in the formation water.Since water can strongly wet and permeate strata,the dissolved inorganic salts migrate into upper strata along with water,giving rise to the formation of a high-concentration inorganic salt field in the strata above geothermal reservoirs.A higher geothermal reservoir temperature corresponds to more significant characteristics mentioned above.Therefore,a medium-to-high temperature geothermal system has a surface geochemical anomaly pattern of high inorganic salt concentrations and low gas concentrations(also referred to as the high-salt and low-gas pattern).This pattern is applied to the surface geochemical exploration of the two geothermal fields in Guangdong Province,i.e.,the Huangshadong geothermal field in Huizhou City and the Xinzhou geothermal field in Yangjiang City,revealing low-concentration gas fields above both.The application results also show that the exposed thermal spring water in both geological fields has higher concentration of dissolved inorganic salt than the surface water and nearby seawater,forming high-amplitude anomalies on the surface above geothermal reservoirs.These characteristics,as well as the measured temperature at known geothermal wells,verify the validity of the high-salt and low-gas pattern of medium-to-high temperature geothermal systems proposed in this study.Moreover,the high-salt and low-gas pattern proposed predicts three favorable medium-to-high temperature geothermal zones in the surface geochemical exploration of the Shiba Basin near the Huangshadong geothermal field. 展开更多
关键词 Medium-to-high temperature Geothermal field geochemical exploration Anomaly pattern
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Regional Geochemical Division—A Tool for Delineating Geochemical Block 被引量:3
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作者 Chen Ming Yan Guangsheng Department of Geology, China University of Geosciences, Beijing 100083 Fan Jizhang Li Jingchao Geomathematics Institute, Changchun University of Science and Technology, Changchun 130026 《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期58-61,共4页
Regional geochemical division is a mapping technique to divide an area into slices where the associations between geochemical elements are relatively simple and uniform. The result of division is expressed on a 2 D ma... Regional geochemical division is a mapping technique to divide an area into slices where the associations between geochemical elements are relatively simple and uniform. The result of division is expressed on a 2 D map. The scheme of regional geochemical division includes non supervised pattern recognition, elementary statistics and factor analysis. A practical example in a gold prospecting area in Jilin, China, and the corresponding explanation are presented. Regional geochemical division is a basic approach to the delineation of the geochemical blocks as well. 展开更多
关键词 regional geochemical exploration regional geochemical division C transformation pattern RECOGNITION geochemical block association of elements.
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Discovery of Wolitu Pb-Zn deposit through geochemical prospecting under loess cover in Inner Mongolia, China 被引量:3
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作者 Fan Yang Mu Kong +5 位作者 Huazhong Liu Jinsong Yu Shaoping Yang Zhihong Hao Dehui Zhang Kuang Cen 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第5期951-960,共10页
We report the finding of the Wolitu Pb-Zn deposit in Inner Mongolia, China, through a series of geochemical surveys. The Wolitu area, located in the loess-cover area in the Hure Banner, Tongliao City,Inner Mongolia, a... We report the finding of the Wolitu Pb-Zn deposit in Inner Mongolia, China, through a series of geochemical surveys. The Wolitu area, located in the loess-cover area in the Hure Banner, Tongliao City,Inner Mongolia, and neighboring the Horqin Sandy Land to the north, had no previous history of Pb-Zn mining or record of Pb-Zn mineralization. Our study identified a large Pb-Zn anomaly with potential zones of mineralization by stream sediment survey. Random rock sampling reveals limonitization at sporadic outcrops in the gullies. The high concentrations of Pb in the residual debris provided guidelines to fix the position for exploratory trench. Oxidized concealed orebodies were identified by trenching.Blind orebodies in veins hosted within the structural zone between slates and marbles of the upper Carboniferous Shizuizi Formation and the Permian granite were discovered by drilling. It is computed that the ore reserve may reach up to 540,000 tones with Pb grade of 1.27% and Zn of 1.9%. This case study is an excellent example for identifying potential polymetallic deposits in loess covered terrains using geochemical exploration. 展开更多
关键词 geochemical exploration Loess-covered area PB-ZN DEPOSIT Resource reserve Inner Mongolia
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Geochemical and Environmental Evaluation of Um Shashoba Gold Mine Area,Southeastern Desert,Egypt 被引量:2
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作者 Mohamed Abdallah Gad DARWISH 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第4期881-898,共18页
A suite of elements(Ag,Au,Ba,Bi,Cd,Co,Cr,Cu,Ga,Hf,Hg,Mn,Mo,Ni,Pb,Rb,Sb,Se, Sr,Te and Zn),total organic carbon(TOC)and pH were analyzed in stream sediment and tailing samples from Um Shashoba area,in order to evalu... A suite of elements(Ag,Au,Ba,Bi,Cd,Co,Cr,Cu,Ga,Hf,Hg,Mn,Mo,Ni,Pb,Rb,Sb,Se, Sr,Te and Zn),total organic carbon(TOC)and pH were analyzed in stream sediment and tailing samples from Um Shashoba area,in order to evaluate Au placer and the sediments being impacted by old mining activities.Analytical results were examined using statistical,graphical and mapping methods.In spite of the results revealing that Au and most of the elements in sediments were in general significantly lower than those in tailing,Au was concentrated in the NE and SW parts forming Au placer.It is remarkably a close association of Au with Hg and Sb;both are useful as pathfinder elements for Au placers.Values of pH could not control a fate of analyzed elements,whereas TOC and Mn oxides and hydroxides could uptake some elements Au,Ba,Co,Cr,Hg,Ni,and Sr.The results also indicated that the sediments were contaminated by anthropogenic factors causing moderate,strong to very strong pollution with respect to Bi,Se and Te,respectively.Additionally,geogenic factors could also contribute elemental enrichment to the drainage system and cause significant toxicity level. 展开更多
关键词 geochemical exploration environmental evaluation Um Shashoba gold mine EGYPT
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Use of portable X-ray fluorescence in the analysis of surficial sediments in the exploration of hydrothermal vents on the Southwest Indian Ridge 被引量:5
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作者 LIAO Shili TAO Chunhui +3 位作者 LI Huaiming ZHANG Guoyin LIANG Jin YANG Weifang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第7期66-76,共11页
Hydrothermal plumes released from the eruption of sea floor hydrothermal fluids contain large amounts of oreforming materials. They precipitate within certain distances from the hydrothermal vent. Six surficial sedime... Hydrothermal plumes released from the eruption of sea floor hydrothermal fluids contain large amounts of oreforming materials. They precipitate within certain distances from the hydrothermal vent. Six surficial sediment samples from the Southwest Indian Ridge(SWIR) were analyzed by a portable X-ray fluorescence(PXRF) analyzer on board to find a favorable method fast and efficient enough for sea floor sulfide sediment geochemical exploration. These sediments were sampled near, at a moderate distance from, or far away from hydrothermal vents. The results demonstrate that the PXRF is effective in determining the enrichment characteristics of the oreforming elements in the calcareous sediments from the mid-ocean ridge. Sediment samples(〉40 mesh) have high levels of elemental copper, zinc, iron, and manganese, and levels of these elements in sediments finer than 40 mesh are lower and relatively stable. This may be due to relatively high levels of basalt debris/glass in the coarse sediments, which are consistent with the results obtained by microscopic observation. The results also show clear zoning of elements copper, zinc, arsenic, iron, and manganese in the surficial sediments around the hydrothermal vent. Sediments near the vent show relatively high content of the ore-forming elements and either high ratios of copper to iron content and zinc to iron content or high ratios of copper to manganese content and zinc to manganese content. These findings show that the content of the ore-forming elements in the sediments around hydrothermal vents are mainly influenced by the distance of sediments to the vent, rather than grain size. In this way, the PXRF analysis of surface sediment geochemistry is found to satisfy the requirements of recognition geochemical anomaly in mid-ocean ridge sediments. Sediments with diameters finer than 40 mesh should be used as analytical samples in the geochemical exploration for hydrothermal vents on mid-oceanic ridges. The results concerning copper, zinc, arsenic, iron, and manganese and their ratio features can be used as indicators in sediment geochemical exploration of seafloor sulfides. 展开更多
关键词 mid-ocean ridge sediments hydrothermal activity portable X-ray fluorescence geochemical exploration
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Application of fractal content-gradient method for delineating geochemical anomalies associated with copper occurrences in the Yangla ore field,China 被引量:3
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作者 Zhen Chen Jianping Chen +1 位作者 Shufang Tian Bin Xu 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第1期189-197,共9页
Fractal and multi-fractal content area method finds application in a wide variety of geological,geochemical and geophysical fields.In this study,the fractal content-gradient method was used on1:10,000 scale to deline... Fractal and multi-fractal content area method finds application in a wide variety of geological,geochemical and geophysical fields.In this study,the fractal content-gradient method was used on1:10,000 scale to delineate geochemical anomalies associated with copper mineralization.Analysis of geochemical data from the Yangla super large Cu-Pb-Zn polymetallic ore district using the fractal content-gradient method,combined with other geological data from this area,indicates that oreprospecting in the ore district should focus on Cu as the main metal and Pb-Zn and Au as the auxiliary metals.The types of deposits include(in chronological order) re-formed sedimentary exhalative(SEDEX),skarns,porphyries,and hydrothermal vein-type deposits.Three ore-prospecting targets are divided on a S-N basis:(1) the Qulong exploration area,in which the targets are porphyry-type Cu deposits;(2) the Zongya exploration area,where the targets are porphyry-type Cu and hydrothermal vein-type Cu-Pb polymetallic deposits;and(3) the Zarelongma exploration area,characterized mainly skarn-type "Yangla-style" massive sulfide Cu-Pb deposits.Our study demonstrates that the fractal content-gradient method is convenient,simple,rapid,and direct for delineating geochemical anomalies and for outlining potential exploration targets. 展开更多
关键词 Fractal method geochemical data Cu-Pb-Zn polymetallic deposits Mineral exploration
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Geochemical characteristics and genetic type of a lithium ore (mineralized) body in the central Yunnan Province, China 被引量:2
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作者 Bai-dong Sun Jun-ping Liu +6 位作者 Xiao-hu Wang Yan Dao Gui-xiang Xu Xiao-zhuang Xue-qing Guan Wei Wang Dong-hu Song 《China Geology》 2019年第3期287-300,共14页
Lithium ore (mineralized) bodies in the area A of central Yunnan Province belong to a sedimentary-type, which are controlled by stratum. The studied ore (mineralized) body mainly occurs in the Middle Permian Liangshan... Lithium ore (mineralized) bodies in the area A of central Yunnan Province belong to a sedimentary-type, which are controlled by stratum. The studied ore (mineralized) body mainly occurs in the Middle Permian Liangshan Formation. This work described the morphology, structures, main ore types and geochemical characteristics of this ore body in detail, and discussed the ore-forming material source, occurrence state of lithium and the formation mechanism of lithium ores to clarify the prospecting marks. In the further exploration, comprehensive evaluation of the lithium resources of known bauxite ore bodies in central Yunnan Province should be strengthened, and the exploration of hidden lithium ore bodies should be intensified in order to discover more large and super-large lithium orebodies, which will fill the gap of the national demand for lithium resources, and promote the national defense construction and new energy industry development. 展开更多
关键词 Sedimentary-type lithium DEPOSIT Stratified DEPOSIT geochemical characteristics METALLOGENIC mechanism Mineral resources exploration engineering Yunnan PROVINCE China
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