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Provenance Study of Fe–Ti Oxide Minerals in the Quaternary Sediments in Yichang Area and Its Implication of Formation Time of the Yangtze Three Gorges, China 被引量:4
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作者 XIANG Fang DU Wen +3 位作者 HUANG Henxu KANG Dongya ZHU Hongbo FENG Qin 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1598-1608,共11页
The Three Gorges are considered to be critical to understand the formation of Yangtze River. Recent research results suggest that the Yangtze Three Gorges was created during the Quaternary but the exact time is debata... The Three Gorges are considered to be critical to understand the formation of Yangtze River. Recent research results suggest that the Yangtze Three Gorges was created during the Quaternary but the exact time is debatable. Fe-Ti oxide minerals are seldom used to study sediment provenance, expecially using scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). In this study, the provenance of Quaternary sediments in Yichang area, which is located to the east of the Yangtze Three Gorges, was investigated by using SEM and EDS to research Fe-Ti oxides. The Panzhihua vanadium titanomagnetite and Emeishan basalt outcrop are located to the west of the Three Gorges. Further, the materials from them are observed in the Quaternary sediments of Yichang area. Fe-Ti oxide minerals from the Huangling granite are observed in the Yunchi and Shanxiyao Formations, which were formed before 0.75 Ma B.P., whereas Fe-Ti oxide minerals from the Huangling granite, Panzhihua vanadium titanomagnetite, and Emeishan basalt are observed in the riverbed and fifth-terrace sediments of the Yangtze River, which were formed after 0.73 Ma B.P.. Thus, we can infer that the Three Gorges formed after the deposition of the Shanxi Formation and before the fifth-terrace; i.e., 0.75-0.73 Ma B.P.. 展开更多
关键词 Yangtze Three Gorges Yichang area quaternary sediments Fe-Ti oxide minerals China
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Effect of quaternary ammonium salts on flotation behavior of aluminosilicate minerals 被引量:8
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作者 赵声贵 钟宏 刘广义 《Journal of Central South University of Technology》 EI 2007年第4期500-503,共4页
The electrokinetic properties and flotation of diaspore, kaolinite, pyrophyllite and illite with quaternary ammonium salts collectors were studied. The results of flotation tests show that the collecting ability of qu... The electrokinetic properties and flotation of diaspore, kaolinite, pyrophyllite and illite with quaternary ammonium salts collectors were studied. The results of flotation tests show that the collecting ability of quaternary ammonium salts for the four minerals is in the order(from strong to weak) ofoctadecyl dimethyl benzyl ammonium chloride(ODBA), cetyl trimethyl ammonium bromide(CTAB), dodecyl trimethyl ammonium chloride(DTAC). Under the condition of alkalescence, it is possible to separate the diaspore from the silicate minerals such as kaolinite, illite and pyrophyllite using quaternary ammonium salts as collector. Isoelectric points (IEP) of diaspore, kaolinite, pyrophyllite and illite are pH=6.0, 3.4, 2.3 and 3.2, respectively. Quaternary ammonium salts can change ζ-potential of the aluminosilicate minerals obviously. The flotation mechanisms were explained by ζ-potential and Fourier transform infrared spectrum (FT-IR) measurements. The results demonstrate that only electrostatic interaction takes place between aluminosilicate minerals (diaspore, kaolinite, pyrophyllite and illite) and quaternary ammonium salts. 展开更多
关键词 aluminosilicate mineral quaternary ammonium salt FLOTATION
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Characteristics of Heavy Minerals and Quantitative Provenance Identification of Sediments from the Muddy Area Outside the Oujiang Estuary Since 5.8 kyr 被引量:4
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作者 SONG Hongying LIU Jinqing +2 位作者 YIN Ping ZHANG Yong CHEN Xiaoying 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第6期1325-1335,共11页
The heavy mineral compositions of the sediments in core D04 with a length of 20.2 m from the muddy area outside the Oujiang Estuary along the coast of Zhejiang-Fujian Provinces have been analyzed. Core D04 can be divi... The heavy mineral compositions of the sediments in core D04 with a length of 20.2 m from the muddy area outside the Oujiang Estuary along the coast of Zhejiang-Fujian Provinces have been analyzed. Core D04 can be divided into three units: DU1(0–7.4 m), DU2(7.4–11.4 m) and DU3(11.4–20.2 m). The results showed that the heavy minerals are authigenic pyrite(65.6%)– hornblende(16.0%) – epidote(4.6%) assemblages. The core sediments are mainly composed of clayey silt, which belongs to the clinoform deposit formed since 5.8 kyr, indicating a weak hydrodynamic environment. The deposition rates changed in the trend of high-low-high upward. Quantitative analysis shows that the core sediments were mainly from the suspended sediments of the Changjiang(Yangtze) River, accounting for 79.2%, with only 10.0% from Oujiang, and 10.8% from other provenance. The Oujiang-derived sediments were gradually increased from the bottom unit DU3(3.1%) to the top unit DU1(17.8%), but the Changjiang-derived sediments were gradually decreased. The source changes are closely related to the development of Yangtze River Delta and Wenzhou Bay, climate changes and human activities. During the period of 2.1–3.7 kyr, the sediment supply was greatly reduced due to the poor reclamation capacity of the river basins, resulting in a low deposition rate. Since 2 kyr, the enhancement of human activities in the Yangtze River Basin and the Oujiang River Basin led to more soils to be eroded and transported to the study area. Due to the short distance of the site of core D04 from the Oujiang River mouth, the study area received more Oujiang-derived sediments when upper unit(DU1) deposited than the lower units(DU2 and DU3). 展开更多
关键词 mud deposit Oujiang ESTUARY MID-HOLOCENE heavy mineral QUANTITATIVE IDENTIFICATION
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Characteristics of Heavy Minerals in Tertiary System of Western Qaidamu Basin 被引量:1
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作者 PENGDe-hua WANGChao-yong 《Journal of China University of Mining and Technology》 EI 2005年第2期91-95,共5页
According to tectonic position and mineral inclusions, supply resource in western Qaidamu basin is di- vided into the front of Aerjinshan mountain and the front of Qimantageshan mountain. The former is mainly composed... According to tectonic position and mineral inclusions, supply resource in western Qaidamu basin is di- vided into the front of Aerjinshan mountain and the front of Qimantageshan mountain. The former is mainly composed of zircon, garnet inclusions, indicating that its mother rocks are mainly metamorphic rocks. Gas and zircon, iron ore, carbon grain inclusions is common in the front of Qimantage mountain, indicating that its mother rock are mainly magmatite and mixed metamorphic rocks. The supply resource is abundant and tectonic movement is active in the joint of the two mountains. The western Qaidamu basin is further divided into 6 heavy mineral sub-regions according to their features of association and stable coefficient of heavy mineral. They are approximately corresponding to their sedimentary environment. Of the 6 sub-regions, the unstable region is corresponding to fluvial fan, middle stable re- gion is corresponding to river-alluvial plain-delta, stable region is corresponding to river-alluvial plain -delta-offshore. The fragment transported distance is presumed based on stable coefficient. In vertical, stable coefficient of heavy min- eral becomes small from Xiaganchai formation to Xiayoushashan formation, indicating that the supply resource be- came nearer and nearer. 展开更多
关键词 Qaidamu basin TERTIARY heavy mineral INCLUSION mother rock
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The Concert between Geology and Artificial Intelligence:Automatic Identification of Heavy Minerals from River Sand
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作者 HAO Huizhen HU Xiumian +1 位作者 GUO Ronghua GU Qing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期21-23,共3页
Heavy minerals with densities higher than 2.8 g.cm-3 are generally considered minor components of sand or sandstone,typically forming 1%of the weight in the samples(Mange and Wright,2007).Heavy-mineral analysis is an ... Heavy minerals with densities higher than 2.8 g.cm-3 are generally considered minor components of sand or sandstone,typically forming 1%of the weight in the samples(Mange and Wright,2007).Heavy-mineral analysis is an effective tool for studying the sedimentary provenance of siliciclastic rocks,reconstructing sedimentary sources to sink routes,subdividing and correlating non-fossiliferous siliciclastic strata. 展开更多
关键词 river SAND heavy MINERAL artificial INTELLIGENCE image analysis
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Sediment Characteristics, Sources, and Transport Patterns in Kompong Som Bay, Cambodia: Indications from Grain Size and Heavy Minerals
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作者 LIU Jinqing CHEN Xiaoying +5 位作者 YIN Ping CAO Ke GAO Fei MENG Yuanku QIU Jiandong LI Meina 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第2期329-339,共11页
In this paper, we analyzed the grain size and heavy mineral compositions of 52 surface sediment samples collected from the Kompong Som Bay of Cambodia and the adjacent rivers to depict the marine sedimentary environme... In this paper, we analyzed the grain size and heavy mineral compositions of 52 surface sediment samples collected from the Kompong Som Bay of Cambodia and the adjacent rivers to depict the marine sedimentary environments and transport processes. Heavy minerals in sediments are dominated by authigenic pyrite, siderite, and tourmaline, with average percentages of 36.52%, 29.02%, and 10.94%, respectively. Two provinces can be divided according to the spatial similarity of minerals. The sediments from Province I, covered by silt grains in the northern bay, are characterized by autogenic pyrite, indicating a weakly reducing environment;whereas in Province II, covered by sand grains in the southern bay, the siderite-tourmaline-authigenic pyrite-zircon-hornblende assemblage occurs, indicating a mild reducing environment and locally oxidizing environment. Most of the sediments in the Kompong Som Bay are introduced from the Preak Piphot River and Srae Ambel River, except that some of them in the south areas come from coastal erosion. Generally, the sediments are difficult to be transported because of the low sediment loads entering the sea and weak hydrodynamic conditions. However, they are transported from the north to the south during the tide ebbing when the hydrodynamic force is much stronger. The sediment distribution and transport patterns are controlled by many factors, including submarine topography, hydrodynamic conditions, the southwest monsoon, land contours, and sediment supply. 展开更多
关键词 heavy mineral PROVENANCE sedimentary environment sediment transport Kompong Som Bay Cambodia
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New insights into multiple provenances evolution of the Jurassic from heavy minerals characteristics in southern Junggar Basin, NW China
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作者 ZHOU Tianqi WU Chaodong +8 位作者 YUAN Bo SHI Zhongkui WANG Jialin ZHU Wen ZHOU Yanxi JIANG Xi ZHAO Jinyong WANG Jun MA Jian 《Petroleum Exploration and Development》 2019年第1期67-81,共15页
The method of random forest was used to classify the heavy mineral assemblages of 2 418 Jurassic samples in the southern Junggar Basin, and determine the distribution of the heavy mineral assemblages from the same pro... The method of random forest was used to classify the heavy mineral assemblages of 2 418 Jurassic samples in the southern Junggar Basin, and determine the distribution of the heavy mineral assemblages from the same provenance systems. Based on the analysis of heavy minerals assemblages, ZTR index, sedimentary characteristics, U-Pb zircon ages, whole-rock geochemical and paleocurrent direction analysis, the study reveals that five important provenances were providing sediments to the southern Junggar Basin in the Jurassic period: The North Tianshan(NTS), Central Tianshan(CTS), Bogda Mountains, Zhayier Mountains and Kalamaili Mountains. During the Early Jurassic, NTS-CTS, Kalamaili Mountains and Zhayier Mountains are primary provenances, Bogda Mountains started to uplift and supply clastic materials in the Middle Jurassic. There are three sedimentary area in the Jurassic of southern Junggar Basin: the western part, the central part and the eastern part. In the western part, the clastic materials of the Early Jurassic was mainly from NTS blocks and Zhayier Mountains, and the sediments were dominantly derived from the Zhayier Mountains during the Middle–Late Jurassic. In the central part, the main provenance of the Early Jurassic switched from NTS to CTS. In the Xishanyao Formation, the main source went back to NTS again. The NTS was the primary provenance during the sedimentary periods of Toutunhe Formation and Qigu Formation. In the eastern part, the contribution of CTS and Kalamaili Mountains were considered as major provenances in the Early Jurassic-Xishanyao Formation, small proportion of sediments were from NTS. The Bogda mountains uplifted and started to provide sediments to the Junggar Basin in the sedimentary period of Xishanyao Formation, and became the major source during the Toutunhe Formation period, with small amount of sediments from CTS. The provenance from CTS was hindered during the sedimentary period of Qigu Formation owing to the uplifting of the Bogda mountains, and the sediments were mainly from the Bogda mountains and NTS. 展开更多
关键词 SOUTHERN JUNGGAR Basin JURASSIC source to sink system provenance heavy minerals ASSEMBLAGES random forest
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Characteristics of Heavy Minerals Composition and Distribution in Jiulong River Estuary Sediment
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作者 徐茂泉 李超 +1 位作者 许文彬 孙美琴 《Marine Science Bulletin》 CAS 2003年第1期75-87,共13页
The bottom sediment samples were gathered during island investigation in 1994 and in the period of carrying out the natural science fund project of Fujian in 1999. The composition, distribution and assemblage characte... The bottom sediment samples were gathered during island investigation in 1994 and in the period of carrying out the natural science fund project of Fujian in 1999. The composition, distribution and assemblage characteristics of heavy minerals which granularity distributes from 0.063 to 0.125 mm in the sediment from Jiulong River estuary are studied in the paper. The results show that there are 49 kinds of heavy minerals and the average content of them is 9.38 %. The dominant and characteristic minerals are magnetite, hematite, epidote, ilmenite, limonite, hornblende, zircon, andalusite, biotite and so on. 4 mineral assemblage ⅠⅡzones (.The watercourse gateway of Jiulong River mineral zone, . The northern estuary ⅢⅣof Jiulong River mineral zone, . The southern estuary mineral zone, . The eastern estuary of Jiulong River mineral zone ), can be divided based on the heavy mineral contents and the distribution characteristics, which not only relates to the matter sources but also is controlled by hydrodynamic condition and the sedimentary environment in the Jiulong River estuary. 展开更多
关键词 Jiulong River estuary heavy mineral distribution characteristics mineral assemblage sedimentary environment
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MATHEMATICAL STATISTICS OF HEAVY MINERALS AND THEIR REE AND TRACE ELEMENTS IN THE NORTHWESTERN SEA AREA OF ANTARCTIC PENINSULA
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作者 Wang Xianlan and Zhao YunlongSecond Institute of Oceanography, SOA, Hangzhou 310012 Beijing Institute of Uranium Geology, Beijing 100013 《Chinese Journal of Polar Science》 1990年第1期27-35,共9页
Based on the analysis and mathematical statistics of quantitative data on both the heavy minerals and their REE (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), trace (Zr, Hf, Th, Ta, U, Rb, Sr, Zn, Co, Ni, Cr, As, Sc) and major (Fe... Based on the analysis and mathematical statistics of quantitative data on both the heavy minerals and their REE (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), trace (Zr, Hf, Th, Ta, U, Rb, Sr, Zn, Co, Ni, Cr, As, Sc) and major (Fe) elements in the surface sediments in the northwestern sea area of Antarctic Peninsula, the authors find that the heavy minerals as the carriers of REE and trace elements should not be overlooked.Q-mode factor analysis of the heavy minerals provides a 3-factor model of the heavy mineral assemblages in the study area, which is mainly controlled by the origin of materials and sea currents. The common factor P1, composed mainly of pyroxene and metal minerals, and common factor P2, composed of hornblende, epidote and accessory minerals, represent two heavy mineral assemblages which are different from each other in both lithological characters and origin of materials. And common factor P3 probably results from mixing of two end members of the above-mentioned assemblages. R-mode group analysis of the heavy minerals indicates that there are two heavy mineral groups in the sea area, which are different from each other in both genesis and origin of materials. With the help of R-mode analysis, 22 elements are divided into 3 groups and 9 subgroups. These element assemblages show that they are genetically related and that they are different in geochemical behaviors during diagenesis and mineral-forming process. In addition, the relationship between the heavy mineral assemblages and the element subgroups is also discussed. 展开更多
关键词 Sea area of Antarctic Peninsula Marine sediments heavy minerals Rare earth and trace elements Statistic analysis.
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Multiple grain-size fraction analysis of heavy minerals and the provenance identification of sediments from the abandoned Huanghe River,eastern China
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作者 Mengyao WANG Bingfu JIN Jianjun JIA 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期921-935,共15页
The quantitative analysis of sediment sources in a sink is an important scientific topic and challenge in provenance research.The characteristics of heavy minerals,combined with the geochemical constituents of detrita... The quantitative analysis of sediment sources in a sink is an important scientific topic and challenge in provenance research.The characteristics of heavy minerals,combined with the geochemical constituents of detrital grains,provide a reliable provenance-tracing approach.We developed a mineral identification method to analyze the multiple grain-size fraction of sediments,from which the elemental geochemistry of hornblende was used to compare the characteristics of sediments from the Huaihe River and Huanghe(Yellow)River in eastern China.Elements that were statistically identified as being able to discriminate sediment provenance were employed to perform a quantitative analysis of the sources of sediments of the abandoned Huanghe River.Results reveal that the Huaihe River is characterized by a high amphibole content of>60%and that the Huanghe and abandoned Huanghe rivers have greater abundances of limonite and carbonate minerals compared with those of the Huaihe River.The contents of trace elements and rare earth elements in hornblende show that the sediments of the abandoned Huanghe River are similar to those of the Huanghe River but different from those of the Huaihe River.Furthermore,chemical mass balance was used to calculate the relative contributions of different provenances of sediment from the abandoned Huanghe River,and nine trace elements of hornblende were identified as discriminators of provenance.Approximately 2%of the hornblende in the abandoned Huanghe River is derived from the Huaihe River and 98%from the Huanghe River.Considering the proportion of hornblende in the total sediment,it is inferred that the contribution of Huaihe River sediment to the abandoned Huanghe River is approximately 0.5%.This study shows that mineral analysis using multiple grain-size fractions(within the wide range of 1Φto 6Φ)with assessment in elemental geochemistry of hornblende can characterize the provenance of fluvial material in coastal zones. 展开更多
关键词 quantitative provenance analysis heavy mineral multiple grain-size fraction HORNBLENDE elemental geochemistry fluvial sediment the abandoned Huanghe River
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Origin of Quaternary Red Clay of Southern Anhui Province 被引量:9
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作者 HUXUEFENG YUANGUODONG 《Pedosphere》 SCIE CAS CSCD 1998年第3期267-272,共6页
The particle size distribution, heavy mineral constituents and rare earth elements (REE) characteristics of the Quaternary red clay of southern Anhui Province were studied to explore the origin of the clay. The resul... The particle size distribution, heavy mineral constituents and rare earth elements (REE) characteristics of the Quaternary red clay of southern Anhui Province were studied to explore the origin of the clay. The results showed that the clay had some properties of areolian deposits, which could be compared with those of the loess in North China; and its chondrite normalized curves of REE were similar to those of the Xiashu loess, implying that they shared the same origin. It was concluded in combination with the results reported by other researchers that the Quaternary red clay of southern Anhui Province originated from aeolian deposits, and this could reveal the cycles of warm and cold climates in the area during the Quaternary period. 展开更多
关键词 heavy mineral constituents particle size distribution quaternary red clay rare earth elements characteristics
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Quantitative Determination of Composition of Quaternary Cementitious Materials
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作者 刘书艳 史才军 +1 位作者 WANG Dehui XIAO Jiangfan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第2期314-320,共7页
Based on the principle of ENV 196-4 "Methods of testing cement - Part 4 Quantitative determination of constituents or Chinese Standard GB/12960-2007 Quantitative measurement of mineral admixtures in cement, methods w... Based on the principle of ENV 196-4 "Methods of testing cement - Part 4 Quantitative determination of constituents or Chinese Standard GB/12960-2007 Quantitative measurement of mineral admixtures in cement, methods were developed for quantitative determination of fly ash, slag and limestone powder in fresh cement pastes, mortars and concretes. Limestone powder was determined using thermal analysis method. The residue content of fly ash on an 80um sieve, and silt contents of aggregate were also considered during the quantitative determination of mineral composition of quaternary cementitious system. With the developed methods, the deviations between the measured and the actual mineral contents of the constituent in the eemantitious material in fresh cement paste, mortar and concrete, were within 3%. 展开更多
关键词 quaternary cementitious material mineral composition selective dissolution thermal analysis quantitative measurement
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Features of the Mineral Composition of the Quaternary Sediments of the Development Areas of the Erosion Processes on the Territory of the Tunkinsk’s Depression
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作者 S.I.Shtel’makh L.A.Pavlova T.G.Ryashchenko 《Journal of Geological Resource and Engineering》 2019年第4期113-122,共10页
The article considers the some features of the Quaternary sediments mineral composition of the development areas of the erosion processes on the territory of the Tunkinsk’s depression.Main objectives of our research ... The article considers the some features of the Quaternary sediments mineral composition of the development areas of the erosion processes on the territory of the Tunkinsk’s depression.Main objectives of our research are to determine the entering forms of Na,Mg,Al,Si,P,S,K,Ca,Ti,Cr,Mn,Fe,Zn,Cu,Zr,and Ba in the composition of the investigated sediments.The mineral composition was studied by the method of an electron probe X-ray spectral microanalysis(XRM)using wave spectrometers,and the method of X-ray diffraction analysis.The localization centers of Cr,Cu,Zn,Zr,and Ba were established in the mineral composition of the studied sediments.Maximum content of BaO(14.42 wt%)was detected in alkali K-feldspar in the clay sediments of modern alluvial complex(aQ4).Crystallochemical formulas of different minerals were obtained. 展开更多
关键词 Electron probe X-ray spectral MICROANALYSIS mineral composition quaternary SEDIMENTS FELDSPARS ore minerals
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Tectonics induced switching of provenance during the Late Quaternary aggradation of the Indus River Valley, Ladakh, India 被引量:2
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作者 Ravish Lal H.S.Saini +1 位作者 N.C.Pant S.A.I.Mujtaba 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第1期285-297,共13页
The Indus River flows through Ladakh, one of the driest and coldest places on earth, in a tectonically active domain. Fluvial, glaciofluvial, lacustrine and debris dominated sequences represent the Late Quaternary sed... The Indus River flows through Ladakh, one of the driest and coldest places on earth, in a tectonically active domain. Fluvial, glaciofluvial, lacustrine and debris dominated sequences represent the Late Quaternary sedimentary record along the river course. Karakoram Fault, a major crustal scaled feature reported to be active during the Quaternary, is associated with the Indus River drainage. Linkages between a major, active fault and deposits formed during the activity period of the fault are explored using heavy mineral deduced provenance and Optically Stimulated Luminescence(OSL) chronology.Five deposits in a ~200 km long stretch of the Indus River have been examined for a ~80 ka period to decipher the climate linked aggradation history. Damming of the Indus River at ~79 ka and existence of the Spituk Lake for >30 ka is demonstrated. Using geology of the provenance in relation to the mineralogical attributes of the Quaternary deposits, the major drainage reorganization when the connection of the Tangtse Valley to the Indus was blocked, is inferred at ~73 ka. It is supported by the geologicalgeomorphological evidence. The study demonstrates the application of provenance linked mineralogy in terrestrial aggradation in a tectonically active region. 展开更多
关键词 Karakoram Fault Indus Drainage reorganization heavy minerals AGGRADATION
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Late Quaternary clay minerals off Middle Vietnam in the western South China Sea: Implications for source analysis and East Asian monsoon evolution 被引量:24
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作者 Christophe COLIN 《Science China Earth Sciences》 SCIE EI CAS 2007年第11期1674-1684,共11页
High-resolution clay mineral records combined with oxygen isotopic stratigraphy over the past 450 ka during late Quaternary from Core MD05-2901 off Middle Vietnam in the western South China Sea are re-ported to recons... High-resolution clay mineral records combined with oxygen isotopic stratigraphy over the past 450 ka during late Quaternary from Core MD05-2901 off Middle Vietnam in the western South China Sea are re-ported to reconstruct a history of East Asian monsoon evolution. Variations in Illite, chlorite, and kaolinite contents indicate a strong glacial-interglacial cyclicity, while changes in smectite content present a higher frequency cyclicity. The provenance analysis indicates a mixture of individual clay minerals from various sources surrounding the South China Sea. Smectite derived mainly from the Sunda shelf and its major source area of the Indonesian islands. Illite and chlorite originated mainly from the Mekong and Red rivers. Kaolinite was provided mainly by the Pearl River. Spectral analysis of the kaolin-ite/(illite+chlorite) ratio displays a strong eccentricity period of 100 ka, implying the ice sheet-forced win-ter monsoon evolution; whereas higher frequency changes in the smectite content show an ice sheet-forced obliquity period of 41 ka, and precession periods of 23 and 19 ka and a semi-precession period of 13 ka as well, implying the tropical-forced summer monsoon evolution. The winter monsoon evolution is generally in coherence with the glacial-interglacial cyclicity, with intensified winter monsoon winds during glacials and weakened winter monsoon winds during interglacials; whereas the summer monsoon evolution provides an almost linear response to the summer insolation of low latitude in the Northern Hemisphere, with strengthened summer monsoon during higher insolation and weakened summer monsoon during lower insolation. The result suggests that the high-latitude ice sheet and low-latitude tropical factor could drive the late Quaternary evolution of East Asian winter and summer monsoons, respectively, implying their diplex and self-contained forcing mechanism. 展开更多
关键词 clay minerals provenance East Asian monsoon late quaternary Middle Vietnam South China Sea
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Heavy minerals clustering analysis in application of provenance analysis of Kong 2 Member in Kongnan area
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作者 Narenna WU 《Global Geology》 2007年第1期44-47,共4页
The main task of provenance analysis is to determine the source of sediments and the position of parent rocks.Provenance analysis may find out the relationship between erosion districts and sediment zone,between the u... The main task of provenance analysis is to determine the source of sediments and the position of parent rocks.Provenance analysis may find out the relationship between erosion districts and sediment zone,between the uplift and the depression in the process of basin development.The authors use the method of heavy mineral clustering analysis and estimate the provenance direction of Huanghua Depression in the Paleogene Kong 2 Member.Research shows that there were five provenance areas of Kong 2 Member in Kongnan area.They are western(Shenusi),northwestern(Cangzhou),eastern(Ganhuatun),northeastern and southeastern.The main provenance areas were northwestern and western,while the southern provenance could not be ruled out.And these areas are consistent with the known provenance areas. 展开更多
关键词 stable heavy minerals clustering analysis provenance analysis Kongnan area Kong 2 Member
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Compositions of heavy minerals in Northeastern China sandlands and provenance analysis 被引量:15
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作者 XIE Jing1,2 & DING ZhongLi1 1 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China 《Science China Earth Sciences》 SCIE EI CAS 2007年第11期1715-1723,共9页
Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun Buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and to... Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun Buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and tourmalines. Heavy mineral assemblages of these three sandlands consist mainly of garnet, ilmenite, epidote and minor amphibole and magnetite. Garnets consist mainly of high Mg type-A ones (58% on average), and minor type-B ones. Toumalines are mainly composed of Mg-rich and minor Fe-rich ones. Compared with those of central-southern Mongolia and central Tarim, these three sandlands are derived from the Phanerozoic rocks of the Central Asian Orogenic Belt and the Archean and Paleoprotorozoic basement rocks of the North China Craton. Our results provide direct evidence that the present-day sands may be reworked from LGM ones. Differences of heavy mineral composi-tions occur between the samples of the three sandlands and Taklimakan Desert, indicating that the material of the western arid regions contributes little to the eastern sandlands. 展开更多
关键词 heavy minerals provenance Northeastern China garnet tourmaline
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Chemical Forms of Heavy Metals in Carbonate-Derived Laterite and Enrichment of Its Iron Oxide Minerals 被引量:10
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作者 朱立军 漆亮 《Chinese Journal Of Geochemistry》 EI CAS 1997年第3期263-270,共8页
In this paper the seven-step continuous extracting method was employed in the studyof chemical forms of the six heavy metals Co, Zn, Pb, Cu, Cr and Mn. The result shows thatthe metals in the laterite are present in th... In this paper the seven-step continuous extracting method was employed in the studyof chemical forms of the six heavy metals Co, Zn, Pb, Cu, Cr and Mn. The result shows thatthe metals in the laterite are present in the chemical form of crystalline iron oxides andresidues, and they are transformed toward organic and exchangeable forms in the surface soil.Linear regression analysis indicates that the above heavy metals have a positive correlation withthe crystalline iron oxide minerals. The crystalline iron oxide minerals have a very importantrole to play in the enrichment of heavy metals, especially the solid components in the laterite. 展开更多
关键词 红土 重金属 氧化铁矿物 化学形式
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Heavy Minerals and Geochemical Characteristics of Sandstones as Indices of Provenance and Source Area Tectonics of the Ogwashi-Asaba Formation, Niger Delta Basin 被引量:1
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作者 O. Innocent Ejeh I. Anthony Akpoborie A. A. Israel Etobro 《Open Journal of Geology》 2015年第8期562-576,共15页
Heavy mineral petrographic and geochemical compositions (major and trace/rare earth elements)?of sandstones obtained from the Oligocene-Miocene Ogwashi-Asaba Formation, Niger Delta were studied to determine their prov... Heavy mineral petrographic and geochemical compositions (major and trace/rare earth elements)?of sandstones obtained from the Oligocene-Miocene Ogwashi-Asaba Formation, Niger Delta were studied to determine their provenance, source area weathering conditions and tectonic setting. The heavy mineral suite (opaque minerals, zircon, tourmaline, and rutile) revealed that the sandstones are mineralogically mature and implied rapid disintegration and chemical decomposition of sediments mostly of recycled orogen. The sandstones were geochemically classified as Fe-sand and partly quartz arenitic. Chemical Index of Alteration and Chemical Index of Weathering values of 89.92% and 91.87% respectively suggest that the source region was predominantly felsic and was subjected to intense chemical weathering probably under tropical palaeoclimatic conditions with abundant rainfall that enhanced sediment recycling. Major element concentration discriminant plots also indicated that the sediments were derived from mixed sources (granitic, gneissic or recycled orogen) under passive margin setting. Chondrite normalized plot of the rare earth element pattern is marked by light rare earth element enrichment and negative Eu anomalies, interpreted to mean that provenance was mainly continental crustal rocks. Trace elemental ratios that are provenance diagnostic (La/Sc, Th/Sc, Cr/Th, La/Co, Th/Co, Th/Cr, Eu/Eu*, and Eu*) all point to sediments derived from felsic source and upper continental crust. The mixed provenance of the sandstones can be traced to the southwestern and southeastern Basement Complex (consisting of granites, gneisses, etc.) and sediments derived from the adjacent sedimentary basins (Anambra and Benue Trough). 展开更多
关键词 PROVENANCE Source Area TECTONICS heavy minerals Geochemical Characteristics SANDSTONES Ogwashi-Asaba Formation Niger Delta BASIN
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Recovery of Total Heavy Minerals from Badlands of Basanputti Village,Odisha
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作者 T Laxmi Rajalaxmi Mohapatra R Bhima Rao 《Journal of Earth Science》 SCIE CAS CSCD 2012年第6期892-899,共8页
The badland topography of Basanputti Village, Ganjam District, Odisha, possesses red sediments. The typical red sediment deposit, on average, consists of 71.8% total heavy minerals (THM), out of which 62.1% are ilme... The badland topography of Basanputti Village, Ganjam District, Odisha, possesses red sediments. The typical red sediment deposit, on average, consists of 71.8% total heavy minerals (THM), out of which 62.1% are ilmenite. The other heavy minerals sillimanite, zircon, garnet, monazite, and pyriboles are in the order of abundance identified. In this present study, Mozley mineral separator has been used to recover THM from red sediment. Mineral separator results indicate that a product ob- tained contains 72.2% by weight with 94.4% THM and 95% recovery. The ilmenite concentrate recov- ered using dry low-intensity magnetic separator from the THM concentrate can be used in pigment in- dustries after suitable pyrometallurgical/chemical processing methods. 展开更多
关键词 red sediment total heavy mineral (THM) Mozley mineral separator Perm roll mag-netic separator ILMENITE zircon.
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