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Soil water movement and deep drainage through thick vadose zones on the northern slope of the Tianshan Mountain: Croplands *** lands

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China Geology 2020年第1期3卷 113-123页

作者： Fang-qiang Sun Li-he Yin Wu-hui Jia Jun Zhang xiao-yong Wang Li-feng Zhu xin-xin Zhang xiao-ping Tang Jia-qiu Dong xi’an center of geological survey China Geological SurveyMinistry of Natural ResourcesXi’an 710054China School of Water Resources and Environment China University of GeosciencesBeijing 100083China Chinese Academy of geological Sciences China Geological SurveyMinistry of Natural ResourcesBeijing 100037China

Regional aridity is increasing under global climate change,and therefore the sustainable use of water resources has drawn attention from scientists and the ***-use changes can have a significant impact on groundwater recharge in arid regions,and quantitative assessment of the impact is key to sustainable groundwater resources *** this study,the changes of groundwater recharge after the conversion of natural lands to croplands were investigated and compared in inland and arid region,i.e.,the northern slope of the Tianshan *** isotopes suggest that soil water in topsoil(<2 m)has experienced stronger evaporation under natural lands than croplands,and then moves downward as a piston *** was estimated by the tracer-based mass balance method,i.e.,chloride and *** rates under natural conditions estimated by the chloride mass balance(CMB)method were estimated to be 0.07 mm/a in deserts and 0.4 mm/a in *** contrast,the estimated groundwater recharge ranged from 61.2 mm/a to 44.8 mm/a in croplands,indicating that groundwater recharge would increase significantly after land changes from natural lands to irrigated croplands in arid *** estimated by the sulfate mass balance method is consistent with that from the CMB method,indicating that sulfate is also a good tracer capable of estimating groundwater recharge.

关键词： Land-use Soil water Groundwater recharge Deep drainage Unsaturated zone Arid regions Cropland Natural land Groundwater survey engineering Tianshan Mountain China

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Distribution Characteristics and Metallogenic Regularity of Graphite Deposits in Qinling Orogen,China

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1244-1263页

作者： FENG Yangwei QU Hongjun YANG Chenyi LV Lushi State Key Laboratory of Continental Dynamics Department of GeologyNorthwest University xi'an Institute of Geology and Mineral Resources xi'an center of geological survey China Geological Survey Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits MLR Shaanxi Earthquake Administration Aerophotogrammetrical surveying and Remote Sensing Bureau CNACG

Qinling orogen is one of the five main repository distribution provinces of large scale graphite resources. Graphite occurrence strata are multitudinous including NeoArchaean group to Neopaleozoic. Mineral deposit types are complete consisting of crystal flaky graphite deposit and aphanitic graphite deposit, ore types of the former are main graphite gneiss, graphite schist and graphitized marble, and ore types of the latter are main graphite layer metamorphosised from coal bed and graphitic carbargilite. At present, most graphite deposits with low research degree only implement preliminary investigations of the graphite resource, which has a good prospect. Based on the basic material of dozens of graphite deposits, spots and plays discovered in the Qinling orogen, this paper applied geologic multidisciplinary analysis method to disclose the graphite deposit types of the Qinling orogen, mainly through outdoors geologic survey and specimen examination with analysis of some typical deposits： regional metamorphism crystal graphite deposits and thermo-contact metamorphic aphanitic graphite deposits, with the control of latitudinally trending regional tectonic, graphite deposits of the Qinling orogen distribute sublatitudinally trending three large ore belts： I the Neoarchean-Proterozoic basement crystal graphite enrichment deposits zone along the south margin of North China plate; II the Carboniferous intermountain basin group aphanitic graphite enrichment deposits zone near the Shangdan suture of the West Qinling; III Paleozoic crystal graphite enrichment deposits zone in the Qinling paleomicroplate of the west part of the East *** are reached from multiple inquiries： Qinling multi-cycle complex continental collision orogen zone has experienced multiple tectonic framework transformation and polyphase tectonic thermal event from NeoArchean Erathem adjointing multiple graphite tectonic mineralization cycle. In the light of chief control of mineralization a

关键词： Qinling orogen graphite deposits graphite gneiss Metallogenic regularity

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Characterizing the Micropores in Lacustrine Shales of the Late Cretaceous Qingshankou Formation of Southern Songliao Basin, NE China

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2267-2279页

作者： GE Mingna REN Shoumai GUO Tianxu ZHOU Zhi WANG Shengjian BAO Shujing Oil and Gas survey China Geological SurveyBeijing 100083China China geological survey Beijing 100037China

Micropores of shale are significant to the gas content and production potential of shale, which has been verified in the research of marine shale gas; while, few studies have been conducted on lacustrine shales. This study collected 42 samples from three wells in the Late Cretaceous Qingshankou Formation of the southern Songliao Basin, NE China, and investigated these samples by the focused ion beam-scanning electron microscope(FIB–SEM) and nitrogen adsorption analysis techniques. Four types of micropores were identified in the samples, i.e., intergranular pore, intracellular pore, organic matter pore and microfracture. The pore structure type is characterized by open slit pores and "ink type" pores which are mainly 1.5–5 nm in diameter with mesopores as the main pores. The mesopores account for 74.01% of the pore volume and 54.68% of the pore surface area. Compared with the lacustrine shales from the Triassic Yanchang Formation in the Ordos Basin and Xujiahe Formation in the Sichuan Basin, the intergranular clay mineral interlayer pores are considered to be the main reservoir space for shale gas storage in the study area, followed by intraparticle pores, organic matter pores and microfractures. Maturity and micropore are the key controlling factors which affect the shale gas content of the Qingshankou Formation in southern Songliao Basin.

关键词： micropores lacustrine shale Cretaceous Qingshankou Formation southern Songliao Basin

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Neoproterozoic(750–711 Ma)Tectonics of the South Qinling Belt,Central China:New Insights from Geochemical,Zircon U-Pb Geochronological,and Sr-Nd Isotopic Data from the Niushan Complex

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 106-121页

作者： WANG Shuo LIU Yunhua YANG Benzhao TAN Le LI xiaoyan DENG Nan School of Earth Sciences and Resources Chang'an UniversityXi'an 710054China geological Team No.1 of Shaanxi Bureau of Geology and Mineral Resources AnkangShannxi 725000 China Longshou Mine of Jinchuan Group Co. LtdJinchangGansu 737100China xi'an Mineral Resources survey center China Geological SurveyXi'an 710100China

The xiejiaba and Fuqiangbei plutons form part of the newly identified Neoproterozoic Niushan complex,which is located in the southern South Qinling belt(SQB).The plutons are compositionally similar,were emplaced at 750–711Ma,and provide insights into Neoproterozoic tectonism within the South Qinling *** xiejiaba pluton contains diorite,quartz diorite,granodiorite,and granite phases,all of which are sub-alkaline and have variable major element compositions with negative correlations between SiO_(2)and MgO,TFe_(2)O_(3),Al_(2)O_(3),CaO,TiO_(2)and P_(2)O_(5).These rocks are enriched in light rare earth elements(LREEs)and large ion lithophile elements(LILEs)and have negative Nb,Ta,P and Ti anomalies,all of which are indicative of arc-type *** Fuqiangbei pluton contains granitoids that are compositionally similar to the rocks in the xiejiaba *** from these plutons have similarε_(Nd)(t)values(1.24–5.99)but very variable(^(87)Sr/^(86)Sr)i values(0.7010–0.7054).Combining these data with the geochemical data for these rocks suggests that the magmas that formed the Niushan complex were derived from the crust–mantle ***,combined with the results of previous research,suggests that the transition from low pressure-low temperature to low pressure-high temperature conditions within a subduction zone caused melting during a period of late subduction and backarc *** constrain the timing of subduction within the South Qinling belt and the northern Yangtze Block(YB)to 750–711 Ma,with this Neoproterozoic subduction associated with an ocean to the north overprinting an existing continental rift-type tectonic setting within the northern margin of the Yangtze Block and the South Qinling belt.

关键词： geochronology geochemistry magmatism tectonics Precambrian South Qinling

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Petrogenesis of the Neoarchean zincian chromite within ultramafic xenoliths,Bastar Craton,India

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Acta Geochimica 2023年第3期42卷 471-487页

作者： Arpita Karmakar Tushar Meshram Mohammad Asif Yogesh Pandey geological survey of India Vasudha BhawanKumarswamy LayoutBangalore 560111India geological survey of India NagpurIndia geological survey of India RaipurIndia

The present study reports and discusses the genesis of zincian chromite in the ultramafic xenoliths from the Dongripali area,Bastar craton,Central *** zincian chromite is in the ultramafic xenoliths of Bengpal supracrustal rock hosted by Neoarchaean Bundeli *** zincian chromite shows a range of Cr_(2)O_(3)(39.69 to 51.66 wt%),Al_(2)O_(3)(05.30 wt%to 08.71 wt%),FeO(21.74 wt%to 27.51 wt%),Fe_(2)O_(3)(10.19 wt%to 19.36wt%)with higher ZnO content ranging from 1.73 wt%to 4.08 wt%.Accordingly,their Cr#[Cr/(Cr+Al)]varies in a narrow range from 0.83 to *** calculated melt composition supports metamorphic or post-magmatic nature rather than common occurrences such as inclusion in diamonds,meteorites,and association with any sulfide-rich mineralised *** reveals that the post-magmatic processes play a vital role in transforming chromite to zincian *** empirical thermometric calculation from chromite,amphibole,and pyroxene support their metamorphic origin and formed during low-P and high-T amphibolite grade facies of metamorphism(~700℃).The Neoarchaean granitic magmatism has a significant role in generating and transferring the heat during contact metamorphism with hydration of ultramafic xenoliths and further alteration,i.e.,*** olivine is a major repository for Mn,Zn,and Co in peridotite/ultramafic;these elements get mobilised during the metamorphism and *** is a possible reason for the mobilisation of zinc and incorporation in the chromite within altered *** a result,chromiterich ultramafic xenolith subjected to metamorphic process gets enrichment of Zn and Fe due to elemental *** converts common chromite into zincian chromite,as reported in altered ultramafics elsewhere.

关键词： Zincian chromite Ultramafic Neoarchaean granitic magmatism High-grade metamorphism

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Geochemical Constrains on Petrogenesis and Tectonic Setting of Volcanic Rocks from the Baimianxia and Sanwan Formations in the Northern Margin of the Yangtze Plate

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1336-1350页

作者： XU Xuey CHEN Junlu1 LI xiangmin MA Zhongping WANG Hongliang LI Ping LI Ting xian Institute of Geology and Mineral Resources China Geological Survey Xi ＇an Shaanxi 710054 China Changan University Xi＇an Shaanxi 710069 China

On the basis of petrogeochemical data, the volcanic lavas of the Baimianxia Formation can be classified into two units： high TiO2 and low TiO2. The TiO2 concentration of the former is generally higher than 1%, which occurs in the lower part with high-grade metamorphism, but the latter is less than 1% and crops out in the upper part with low-grade metamorphism. The high-TiO2 unit is dominated by tholeiitic lavas showing high rare earth element （REE） contents （~REE = 83.4-180.8 pg/ g）, high light/heavy REE （LREE/HREE） ratios （LREE/HREE=2.17-5.85） and weak negative Eu anomaly （Eu=0.79-1.01）. Its trace element patterns display weak Nb-Ta anomalies with respect to Th, K, La, Ce, showing within-plate basalt affinities. In contrast, the low-TiO2 unit is characterized by low REE contents, low LREE/HREE ratios, and pronounced Nb-Ta anomalies, indicating typical arc or continental arc signature. Chondrite-normalized REE patterns of basalts and andesites from the Sanwan Formation are flat or LREE depletion, which is very similar to normal mid-oceanic basalt. Therefore, we suggest that these lavas should be formed in a back-arc basin setting. Sr-Nd isotopic data of the basalt in the lower part suggest that the rocks would have been formed in ~1144 Ma. Based on the geochemical and isotopic features of the basalts, we suggest that these rocks in the low part of the Baimianxia Formation should originate from an asthenospheric oceanic-island basalt-like mantle source, which may be produced by partial melting of garnet lherzolite, and significantly underwent fractional crystallization and crustal or lithospheric mantle contamination en route to the surface. However, laser ablation inductively coupled plasma mass spectrometry zircon U-Pb dating of the basalt sample from the upper part of the Baimianxia Formation gives a 437 Ma, indicating a Early Paleozoic age. The geochemical analysis in this paper suggests that they may originate from an arc or continental arc in response to aqueou

关键词： petrogenesis petrogeochemistry U-Pb dating Baimianxia and Sanwan Formations

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Geochronology and Petrogenesis of Granitoid Intrusions in the Feidong District, Southern Tan-Lu Fault Zone, China

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 1960-1976页

作者： FU xiang ZHANG Dayu YAO Ziwei REN Kangda DENG Yufeng LI Jiahao JIANG Ren YUAN Feng School of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China Nanjing geological survey center China Geological SurveyNanjing 210016China

The Feidong district is located in the southern segment of the Tan-Lu fault zone that separates the South China Block(NCB)from the North China Craton(NCC).We report zircon U-Pb geochronology and Hf isotope data,as well as whole-rock geochemistry for xishanyi granodiorite and Jianshan granite in the Feidong *** U-Pb dating results show that the emplacement ages of the xishanyi and Jianshan intrusions are 124±3 Ma and 130±1 Ma respectively,coeval with magmatic events linked to large-scale lithospheric thinning in eastern *** whole-rock geochemistry of the xishanyi and Jianshan intrusions demonstrate that they are peraluminous,high potassium calc-alkaline I-type granites with adakitic *** intrusions underwent weak crustal assimilation during *** in situ zirconε(Hf)(t)values of the xishanyi granodiorites range from-26.4 to-21.8,with T(DM2)model ages of 2552 to 2841 *** in situ zirconε(Hf)(t)values of the Jianshan granite are from-27.5 to-23.0 with T(DM2)model ages of 2632 to 2904 *** peak age of inherited zircon grains from the xishanyi granodiorite and the Jianshan granite were^2.07 Ga and^1.94 Ga,*** compared with the regional magmatism,we suggest that both the xishanyi and Jianshan granitoid intrusions were derived from partial melting of the NCC lower crust.

关键词： Granitoid intrusion Petrogenesis Feidong district Tan-Lu Fault Zone

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Paleo-Earthquakes along the Zheduotang Fault,xianshuihe Fault System,Eastern Tibet:Implications for Seismic Hazard Evaluation

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Journal of Earth Science 2022年第5期33卷 1233-1245页

作者： Guifan Chen Mervin Bartholomew Demin Liu Kai Cao Minxuan Feng Dun Wang School of Earth Sciences China University of GeosciencesWuhan 430074China Three Gorges Geotechnical Consultants Co. Ltd.Wuhan 430074China Department of Earth Sciences University of MemphisMemphisTN38152USA xi’an center of geological survey China Geological SurveyXi’an710054China

The Kangding City in eastern Tibet is at high risk due to frequent strong earthquakes along the xianshuihe sinistral strike-slip fault bounding the Chuandian Block to the *** knowledge of paleo-seismicity recurrence along this fault system is key to the evaluation of earthquake hazards in this region;thus,more accurate paleoseismic information are *** examined the paleo-seismicity along the Zheduotang fault in the central segment of the xianshuihe fault system by applying the field investigation,trenching,and Quaternary dating methods(e.g.,OSL and ^(14)C).Field observations found~8.5 m offset of stream by sinistral slip along the Zheduotang *** trenched the central fault zone of the Zheduotang fault and found that the colluvial wedges and five buried,discontinuous,A-soil horizons progressively have been offset in the shallow graben on the SW-side of the main fault indicative of the *** dating results of OSL and ^(14)C,in line with existing data,enable us to establish the paleo-seismic history of the Zheduotang *** shows at least eight surface ruptures in the last 7500 years identified from displaced buried soils,colluvial wedges and *** study reveals~100 years minimum paleo-earthquake recurrence,suggesting potential large earthquakes in the Kangding area in the future.

关键词： Tibetan Plateau xianshuihe fault system paleo-seismicity trench recurrence geophysics

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Geochemistry of Late Triassic pelitic rocks in the NE part of Songpan-Ganzi Basin,western China:Implications for source weathering,provenance and tectonic setting

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Geoscience Frontiers 2012年第5期3卷 647-660页

作者： Yah Tang Longkang Sang Yanming Yuan Yunpeng Zhang Yunlong Yang College of Earth Science and Resources Chang'an University Xi'an 710054 PR China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 PR China xi'an center of geological survey China Geological Survey Xi'an 710054 PR China SINOPEC Exploration Southern Company Chengdu 610082 PR China

Major, trace and rare earth element （REE） concentrations of Late Triassic sediments （fine- grained sandstones and mudstones） from Hongcan Well 1 in the NE part of the Songpan-Ganzi Basin, western China, are used to reveal weathering, provenance and tectonic setting of inferred source areas. The Chemical Index of Alteration （CIA） reflects a low to moderate degree of chemical weathering in a cool and somewhat dry climate, and an A-CN-K plot suggests an older upper continental crust prove- nance dominated by felsic to intermediate igneous rocks of average tonalite composition. Based on the various geochemical tectonic setting discrimination diagrams, the Late Triassic sediments are inferred to have been deposited in a back-arc basin situated between an active continental margin （the Kunlun- Qinling Fold Belt） and a continental island arc （the Yidun Island Arc）. The Triassic sediments in the study area underwent a rapid erosion and burial in a proximal slope-basin environment by the petrographic data,while the published flow directions of Triassic turbidites in the Aba-Zoige region was not supported Yidun volcanic arc source. Therefore, we suggest that the Kunlun-Qinling terrane is most likely to have supplied source materials to the northeast part of the Songpan-Ganzi Basin during the Late Triassic.

关键词： Fine-grained sandstone-mudstone Geochemistry Source area weathering Provenance Tectonic setting Songpan-Ganzi Basin,China

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Petrogenesis and Tectonic Implications of A-type Granites in Zhaheba in the East Junggar Region of xinjiang,China:Evidence from Geochronology,Geochemistry and Sr-Nd Isotopic Compositions

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Acta Geologica Sinica(English Edition) 2022年第3期96卷 938-953页

作者： TANG Hejun MENG Guixiang WU Zhenhan WANG Zhaolin DENG Zhen YAN Jiayong QI Guang XUE Ronghui Chinese Academy of geological Sciences China Geological SurveyMinistry of Natural ResourcesBeijing 100037China SinoProbe center Chinese Academy of Geological SciencesChina Geological SurveyMinistry of Natural ResourcesBeijing 100037China

The magma source,petrogenesis,tectonic setting and geochronology of the late Paleozoic A-type granites widely exposed in the Zhaheba area,East Junggar,have thus far not been well-constrained.A better understanding of these issues will help to reveal the magmatic processes and continental growth of Central *** A-type granites in Zhaheba include the Ashutasi alkaline granites and the Yuyitasi syenogranites,which were emplaced at 321.5±4.8 Ma and 321.7±0.6 Ma,*** major rock-forming minerals are orthoclase,perthite,arfvedsonite and quartz,which exhibit the following principal geochemical characteristics of A2-type granites.(1)Their REE distribution curves each exhibit a‘V’-shaped pattern and a marked depletion in *** are rich in large-ion lithophile elements Rb,Th and U as well as high-field-strength elements Nb,Ta,Zr and Hf,but significantly depleted in Ba,Sr,P and Ti.(2)Their(^(87)Sr/^(86)Sr)i values(0.7021-0.7041),εNd(t)values(4.57-5.16)and REE distribution patterns are in basic agreement with those of the Kalamaili A-type granite belt in East *** T DM2 values of the alkaline granites and syenogranites range from 661 to 709 *** A-type granites may be the products of upwelling asthenosphere-triggered partial melting of immature lower *** alkaline granites were late-stage products of crystallization and *** to the syenogranites,the alkaline granites are significantly lower in K_(2)O,Na_(2)O,Al_(2)O 3,FeO,MgO and CaO,but significantly higher in incompatible elements(e.g.,SiO_(2),Rb,and Sr).The magmatic crystallization temperatures of the syenogranites and alkaline granites are 874℃ and 819℃,*** their age gradually decreases(peak ages:322 Ma and 307 Ma,respectively),there is a gradual decrease in the T_(DM2)of the A-type granites and a gradual increase in theεNd(t)value from the Ulungur belt to the Kalamaili belt in East *** study of A-type granites is therefore one of the keys to understandi

关键词： A-type granite Zircon U-Pb Sr-Nd isotopes post-collision East Junggar

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