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The Determination of Promising Mineral Zones in 1:100,000 Varamin Sheet Based on Geochemical Studies (heavy minerals)

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Open Journal of Geology 2016年第8期6卷 745-756页

作者： Seyyed Reza Mortazavi Ghodratollah Mohammadi Department of Mining Engineering Islamic Azad University South Tehran Branch Tehran Iran

In many parts of the world, data obtained from geochemical exploration of stream sediments are integrated with geological and geophysical data as one of the most efficient methods of exploring potential deposits at regional and semi-detailed scales. The aim of regional investigation is to study large areas to identify anomalies that might have been arisen from increased concentrations of an element or some elements in a region. A total of 78 geochemical samples were taken from Varamin sheet to identify regions of anomalies. The following information was used to perform a detailed geochemical exploration, in particular for geochemical sampling. 1) 1:100,000 geological map of Varamin. 2) 1:50,000 topographic maps of the region. 3) 1:100,000 airborne geophysical map of the region to locate shallow intrusions and hidden faults. The sampling network was designed using the above data and the analysis of 1:500,000 topographic maps. The sampling density was higher around faults and apparent and hidden intrusions, and lower in plains and lowlands.

关键词： Geochemical heavy minerals Varamin Promising Mineral Determination

MATHEMATICAL STATISTICS OF heavy minerals AND THEIR REE AND TRACE ELEMENTS IN THE NORTHWESTERN SEA AREA OF ANTARCTIC PENINSULA

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Chinese Journal of Polar Science 1990年第1期1卷 27-35页

作者： Wang Xianlan and Zhao YunlongSecond Institute of Oceanography, SOA, Hangzhou 310012 Beijing Institute of Uranium Geology, Beijing 100013

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.

关键词： Sea area of Antarctic Peninsula Marine sediments heavy minerals Rare earth and trace elements Statistic analysis.

Compositions of heavy minerals in Northeastern China sandlands and provenance analysis

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Compositions of heavy minerals in Northeastern China sandlan...

The Mamfe Basin in the southern Benue trough extension between Cameroon and Nigeria:Gem origin and problem of lithostratigraphic nomenclature and marine transgression

中国科学院地质与地球物理研究所2007学术年会

作者： XIE Jing~(1,2+) & DING ZhongLi~1 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China

Sand samples deposited since the Last Glacial Maximum(LGM) from the Hulun Buir,Horqin and Otindag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and *** mineral assemblages of these three sandlands consist mainly of garnet,ilmenite,epidote and minor amphibole and *** consist mainly of high Mg type-A ones(58%on average),and minor type-B *** are mainly composed of Mg-rich and minor Fe-rich *** 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 *** results provide direct evidence that the present-day sands may be reworked from LGM *** of heavy mineral compositions 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.

关键词： heavy minerals provenance Northeastern china garnet tourmaline

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Acta Geochimica 2023年第3期42卷 495-516页

作者： Milan Stafford Tchouatcha Primus Tamfuh Azinwi Christel Sobdjou Kemteu Augustin Desire Balla Ondoa Leopold Darlus Ngantchu Basil Azeh Anong Courage Gabvourta Department of Earth Sciences Faculty of ScienceUniversity of DschangP.O.Box 67DschangCameroon Department of Soil Science Faculty of Agronomy and Agricultural SciencesUniversity of DschangP.O.Box 222DschangCameroon Department of Mining and Mineral Engineering National Higher Polytechnic InstituteUniversity of BamendaP.O.Box 39BambiliCameroon Department of Earth Sciences Faculty of ScienceUniversity of YaoundeIP.O.Box 812Yaounde´Cameroon Department of Earth Sciences Faculty of ScienceUniversity of NgaoundereP.O.Box 454NgaoundereCameroun

The Mamfe Basin has been the subject of many studies,but some debates persist,especially concerning the stratigraphic nomenclature,corundum origin,and marine *** aims of this work are(1)to propose a new lithostratigraphic nomenclature of the Mamfe Basin formation based on new field observations,(2)to determine the source rock distribution and the origin of gem deposits and(3)to correlate the Cameroon section of the Mamfe Basin with the Nigerian *** main results show that the name Manyu River Group is more appropriate as the Manyu River crosses all the facies in the Mamfe sedimentary Basin belonging to the Manyu *** to the facies analysis,the age of deposition,the mineralogic and geochemical data such as the V ***2O3andΣREE ***_(2)O_(3),TiO_(2)MgO,Na_(2)O,P_(2)O_(5),and CaO diagrams,this Group is composed of at least five Formations,including four Cretaceous Formations,from bottom to top:the Etoko Formation(alluvial and fluvial channel to fluvio-lacustrine deposits),the Nfaitok Formation(lagoonal deposits),the Bachuo Ntai Formation(fluvial braided channels or fluvio-deltaic environment)and the Eyumojock/NsanaragatiFormation(fluvio-lacustrine deposits)and the new Cenozoic Formation named Bakebe Formation(fluvio-lacustrine deposits).The gem minerals such as corundum,rutile,or tourmaline in the Cretaceous deposits of the Mamfe Basin are mainly detrital as indicated by the presence of worn shapes and fragments of these *** presence of sapphire in the AlboCenomanian deposits indicates a Precambrian age of the felsic source rock,likely the plutonic rocks such as granite or pegmatite as indicated by the abundance of tourmaline and high LREE/HREE ratios(14.81–34.29)and slightly negative and positive Eu anomalies(0.85–1.15).This marine incursion in the Mamfe Basin was probably from West Nigeria,according to the geographic location of the Mamfe Basin and the general palaeogeographic evolution of the Benue Trough.

关键词： Lithostratigraphy Marine transgression heavy minerals Sapphires Mamfe Basin Benue Trough

Grain-size and compositional variability of Yarlung Tsangpo sand(Xigaze transect,south Tibet):Implications for sediment mixing by fluvial and aeolian processes

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Journal of Palaeogeography 2023年第2期12卷 195-210页

作者： Wen Lai Wen-Dong Liang Xiu-Mian Hu Eduardo Garzanti Hua-Yu Lu Xiao-Long Dong Frontiers Science Center for Critical Earth Material Cycling School of Geography and Ocean ScienceNanjing UniversityNanjing 210023Jiangsu ProvinceChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Institute of Sedimentary GeologyChengdu University of TechnologyChengdu 610059Sichuan ProvinceChina State Key Laboratory of Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023Jiangsu ProvinceChina Department of Earth and Environmental Sciences Universita di Milano-BicoccaMilano 20126Italy

Studying the grain-size dependent compositional variability in modern river sediments provides a key to decipher the information stored in the sedimentary archive and reconstruct the evolution of the Earth’s surface in the past. Bedload sand along the Xigaze cross section of the Yarlung Tsangpo(upper Brahmaputra River) ranges in mean grain size from 0.72 Φ to 3.21 Φ, is moderately to poorly sorted and slightly platykurtic to moderately leptokurtic with sub-angular to sub-spherical grains. Litho-feldspatho-quartzose to feldspatholitho-quartzose sand(Q 43%-65%;F 13%-44%;L 11%-28%) contains 3.4%-14.4% heavy minerals including amphibole(64%-89%), epidote(4%-11%), chloritoid(0-10%), and clinopyroxene(2%-6%). The marked textural and compositional variability observed across the Xigaze transect of the Yarlung Tsangpo mainstem is controlled by both fluvial and aeolian processes, including repeated reworking by westerly and glacial winds,as well as by local contributions from northern and southern tributaries draining the Lhasa Block and the Himalayan Belt, respectively. The modern sedimentary case here will shed new light on interpreting paleogeography and provenance.

关键词： Modern fluvial sediments Sand petrography heavy minerals Fluvial/aeolian interactions Endmember grain-size modeling Lhasa Block Himalayan Belt

A heavy mineral viewpoint on sediment provenance and environment in the Qiongdongnan Basin

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Acta Oceanologica Sinica 2015年第4期34卷 41-55页

作者： LIU Xiaofeng ZHANG Daojun ZHAI Shikui LIU Xinyu CHEN Hongyan LUO Wei LI Na XIU Chun Key Laboratory of Submarine Geosciences and Prospecting Techniques of Ministry of Education College of Marine Geosciences Ocean University of China Zhanjiang Branch of China National Offshore Oil Corporation (CNOOC) Limited

Based on heavy mineral data in core samples from eleven drillings, supplemented by paleontological, element geochemical and seismic data, the evolution of sediment provenance and environment in the Qiongdongnan Basin(QDNB) was analysed. The results show that the basement in the QDNB was predominantly composed of terrigenous sediments. Since the Oligocene the QDNB has gradually undergone transgressions and evolution processes in sedimentary environment from terrestrial-marine transitional to littoral-neritic, neritic, and bathyal roughly. The water depth showed a gradually increasing trend and was generally greater in the southern region than that in the northern region in the same time. With changes in sedimentary environment, provenances of the strata(from the Yacheng Formation to the Yinggehai Formation) showed principal characteristics of multisources, evolving from autochthonous source, short source to distant source step by step. During the Early Oligocene, the sediments were mainly proximal basaltic pyroclastic source and adjacent terrigenous clastic source, afterwards were becoming distant terrigenous clastic sources, including Hainan Island on the north,Yongle Uplift on the south, Shenhu Uplift on the northeast, the Red River System on the northwest and Indochina Peninsula on the southwest, or even a wider region. The Hainan Island provenance began to develop during the Early Oligocene and has become a main provenance in the QDNB since the Middle Miocene. The provenances from Yongle Uplift and Shenhu Uplift most developed from the Late Oligocene to the Early Miocene and gradually subsided during the Middle Miocene. During the Late Miocene, as a main source of sediments filled in the central canyon, the Red River System provenance added to the QDNB massively, whose impact terminated at the end of the Pliocene. The western Yinggehai Basin(YGHB) provenance derived from Indochina Peninsula had developed from the Pliocene on to the Pleistocene. In addition, the m

关键词： heavy minerals provenance sedimentary environment Qiongdongnan Basin northern South China Sea

Dynamical Control of Asymmetrically Oblique Tidal Currents to the Sedimentary Characteristics and Development of Linear Sand Ridges in the Liaodong Shoal, East Bohai Sea

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Journal of Ocean University of China 2020年第1期19卷 101-112页

作者： ZHANG Lianjie ZHU Longhai WU Jianzheng HU Rijun WANG Peng ZHANG Pan College of Marine Geosciences Ocean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationOcean University of ChinaQingdao 266100China National Marine Environmental Monitoring Center Dalian 116000China

The Liaodong Shoal is a group of linear sand ridges located in the east Bohai Sea of *** this study,54 surface sediment samples have been collected,current measurements at 4 stations have been carried out and bathymetric data were *** current directions are rightward deflected relative to the strikes of the sand *** by the narrowing effect of the ridge,the current velocities exhibited an anti-‘C’type vertical *** velocities of the lower currents linearly correlate with the water *** near-bed current velocities over the troughs are estimated to be higher than those over the ridges,and this feature could be explained by the loss of kinetic energy together with the conversion between kinetic energy and gravitational potential *** sedimentary characteristics that are compatible with the tidal dynamics are developed across the ridges and troughs,including grain size compositions,grain size parameters,mineral compositions and Dhm *** existence of the angles between the current directions and the strikes of the sand ridges is the key factor for the growth of the sand *** asymmetric hydrodynamic features between the flood and ebb currents lead to the differences in the topographical and sedimentary characteristics on both sides of a sand *** material supply led to the degradation of the sand ridges,and the reduction of the tidal current intensity has led to the development of the subordinate sand ridges in the *** ridges are migrating.

关键词： Liaodong Shoal tidal current ridge heavy minerals sedimentary characteristic development and evolution

Petrography of Middle Jurassic to Early Cretaceous sandstones in the Kutch Basin,western India:Implications on provenance and basin evolution

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Journal of Palaeogeography 2018年第3期7卷 239-252页

作者： Angana Chaudhuri Santanu Banerjee Emilia Le Pera Department of Earth Sciences Indian Institute of Technology Bombay Dipartimento di Biologia Ecologia e Scienze della Terra University della

This paper investigates the provenance of Middle Jurassic to Early Cretaceous sediments in the Kutch Basin, western India, on the basis of mineralogical investigations of sandstones composition （Quartz-Feldspar-Lithic （QFL） fragment）, Zircon-Tourmaline-Rutile （ZTR） index, and mineral chemistry of heavy detrital minerals of the framework. The study also examines the compositional variation of the sandstone in relation to the evolution of the Kutch Basin, which originated as a rift basin during the Late Triassic and evolved into a passive margin basin by the end Cretaceous. This study analyzes sandstone samples of Jhumara, Jhuran and Bhuj Formations of Middle Jurassic, Upper Jurassic and Lower Cretaceous, respectively, in the Kutch Mainland. Sandstones record a compositional evolution from arkosic to subarkosic as the feldspar content decreases from 68% in the Jhumara Formation to 27% in the Bhuj Formation with intermediate values in the Jhuran Formation. The QFL modal composition indicates basement uplifted and transitional continental settings at source. heavy mineral content of these sandstones reveals the occurrence of zircon, tourmaline, rutile, garnet, apatite, monazite and opaque minerals. Sub-rounded to well-rounded zircon grains indicate a polycyclic origin. ZTR indices for samples in Jhumara, Jhuran and Bhuj Formations are 25%, 30% and 50% respectively. Chemistry of opaque minerals reveals the occurrence of detrital varieties such as ilmenite, rutile, hematite/magnetite and pyrite, in a decreasing order of abundances. Chemistry of ilmenites in the Jhumara Formation reveals its derivation from dual felsic igneous and metabasic source, while those in Jhuran and Bhuj Formations indicate a metabasic derivation. Chemistry of garnet reveals predominantly Fe-rich （almandine） variety of metabasic origin. X-ray microscopic study provides the percentage of heavy minerals ranging from 3% to 5.260. QFL detrital modes reflect the evolution of the basin from an active rif

关键词： Siliciclastic provenance Tectonic setting heavy minerals Mineral chemistry X-ray microscopy Mesozoic,Kutch Basin

Lithological indicators of discontinuities in mountain soils rich in calcium carbonate in the Polish Carpathians

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Journal of Mountain Science 2020年第5期17卷 1058-1083页

作者： Joanna Beata KOWALSKA Bartlomiej KAJDAS Tomasz ZALESKI Depatment of Soil Science and Agrophysics University of AgricultureAl.Mickiewicza 2131-120 KrakowPoland Natural Science Education Centre Jagiellonian UniversityGronostajowa 530-387 KrakowPoland

Six soils located within the Polish Carpathians,developed on calcium carbonate–rich sedimentary parent materials and representing various reference groups,were investigated in order to detect the lithic *** propose using a multidirectional approach to assess the lithic discontinuity in these soils,one that includes grain size distribution,geochemical composition,heavy mineral content and micromorphology,supported by a traditional soil survey.A further aim of this process was to identify the possible admixture of allochthonous material of aeolian *** studied soils presented lithic discontinuities mostly at the contact of underlying calcium carbonate–rich coarsegrained slope deposits with the overlaying colluvium layer having a lower content of rock *** significant changes in grain size distribution,especially in the silt and sand content,as well as high Uniformity Values and partially,high Lithological Discontinuity Index values,confirmed the occurrence of a lithic discontinuity in all studied *** heterogeneity in the soil profiles was also confirmed by the distribution of the major oxides;however,their distribution did not clearly indicate the lithic *** most visible distinctions were noted from CaO content,which resulted from the deposition of carbonate-free materials(aeolian silts)and their mixing with the calcium carbonate–rich parent ***,the analysis of heavy mineral content confirmed the allochthonous origin of the upper(and in some cases also the middle)parts of all profiles,which was manifested by the presence of highly weathering-resistant minerals such as zircon,epidote and various types of *** micromorphological features of some of the studied soils showed distinctiveness within the soil profile,manifested by changes in b-fabric pattern,the occurrence and distribution of secondary carbonate and the coarse and fine coarse and fine *** on the high content of silt within the u

关键词： Lithic discontinuities heavy minerals Geochemistry Slope processes Micromorphology Uniformity Values