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Ordovician Granitoids and Silurian Mafic Dikes in the Western Kunlun Orogen, Northwest China:Implications for Evolution of the Proto-Tethys

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 30-49页

作者： ZHANG Qichao WU Zhenhan LI Shan LI Kan LIU Zhiwei ZHOU Qing Chinese Academy of Geological Sciences key laboratory of deep-earth dynamics Ministry of Natural Resources Institute of Geology Chinese Academy of Geological Sciences Xi'an Institute of Geology and Mineral resources Chinese Geological Survey Chengdu Institute of Geology and Mineral resources Chinese Geological Survey

The western Kunlun orogen in the northwest Tibet Plateau is related to subduction and collision of Proto-and Paleo-Tethys from early Paleozoic to early Mesozoic. This paper presents new LA-ICPMS zircon U-Pb ages and Lu-Hf isotopes, whole-rock major and trace elements, and Sr–Nd isotopes of two Ordovician granitoid plutons(466–455 Ma) and their Silurian mafic dikes(～436 Ma) in the western Kunlun orogen. These granitoids show peraluminous high-K calcalkaline characteristics, with(^(87)Sr/^(86)Sr)_i value of 0.7129–0.7224, ε_(Nd)(t) values of -9.3 to -7.0 and zircon ε_(Hf)(t) values of -17.3 to -0.2, indicating that they were formed by partial melting of ancient lower-crust(metaigneous rocks mixed with metasedimentary rocks) with some mantle materials in response to subduction of the Proto-Tethyan Ocean and following collision. The Silurian mafic dikes were considered to have been derived from a low degree of partial melting of primary mafic magma. These mafic dikes show initial ^(87)Sr/^(86)Sr ratios of 0.7101–0.7152 and ε_(Nd)(t) values of -3.8 to -3.4 and zircon ε_(Hf)(t) values of -8.8 to -4.9, indicating that they were derived from enriched mantle in response to post-collisional slab break-off. Combined with regional geology, our new data provide valuable insight into late evolution of the Proto-Tethys.

关键词： High-K calc-alkaline granitoids mafic dikes Western Kunlun Orogen Proto-Tethys

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Carboniferous Highly Fractionated I-type Granites from the Kalamaili Fault Zone, Eastern Xinjiang, NW China: Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2019年第5期93卷 1169-1187页

作者： SONG Peng WANG Tao TONG Ying ZHANG Jianjun HUANG He ZHANG Lei QIN Qie SHEN Huan key laboratory of deep-earth dynamics of ministry of natural resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Beijing SHRIMP Center Beijing 100037China China University of Geosciences Beijing 100037China

Carboniferous magmatism is one of the most important tectonothermal events in the Central Asian Orogenic Belt(CAOB). However, the final closure time of the Kalamaili Ocean between East Junggar and Harlik Mountain is still debated. Early Carboniferous(332 Ma) and late Carboniferous(307-298 Ma) granitic magmatism from Kalamaili fault zone have been recognized by LA-ICP-MS zircon U-Pb dating. They are both metaluminous highly fractionated I-type and belong to the high-K calc-alkaline. The granitoids for early Carboniferous have zircon εHf(t) values of-5.1 to +8.5 with Hf model ages(TDM2) of 1.78-0.83 Ga, suggesting a mixed magma source of juvenile material with old continental crust. Furthermore, those for late Carboniferous have much younger heterogeneous zircon εHf(t) values(+5.1 to +13.6) with Hf model ages(TDM2=1.03-0.45 Ga) that are also indicative of juvenile components with a small involvement of old continental crust. Based on whole-rock geochemical and zircon isotopic features, these high-K granitoids were derived from melting of heterogeneous crustal sources or through mixing of old continental crust with juvenile components and minor AFC(assimilation and fractional crystallization). The juvenile components probably originated from underplated basaltic magmas in response to asthenospheric upwelling. These Carboniferous highly fractionated granites in the Kalamaili fault zone were probably emplaced in a post-collisional extensional setting and suggested vertical continental crustal growth in the southern CAOB, which is the same or like most granitoids in CAOB. This study provides new evidence for determining the post-accretionary evolution of the southern CAOB. In combination with data from other granitoids in these two terranes, the Early Carboniferous Heiguniangshan pluton represents the initial record of post-collisional environment, suggesting that the final collision between the East Junggar and Harlik Mountain might have occurred before 332 Ma.

关键词： highly fractionated granite petrogenesis carboniferous Kalamaili fault zone post-collisional magmatism

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Optimized parameters of downhole all-metal PDM based on genetic algorithm

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Petroleum Science 2024年第4期21卷 2663-2676页

作者： Jia-Xing Lu Ling-Rong Kong Yu Wang Chao Feng Yu-Lin Gao China University of Geosciences(Beijing) Beijing100083China key laboratory on deep Geo-Drilling Technology of ministry of natural resources Beijing100083China

Currently,deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power *** all-metal positive displacement motor,known for its robust performance,is a critical choice for such *** dimensions of the PDM are crucial for its performance *** enhance this,optimization of the motor's profile using a genetic algorithm has been *** design process begins with the computation of the initial stator and rotor curves based on the equations for a screw *** curves are then refined using the least squares method for a precise *** this,the PDM's mathematical model is optimized,and motor friction is *** genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions,including the isometric radius coefficient,eccentricity distance parameter,overflow area,and maximum slip *** optimization yields the ideal profile parameters that enhance the motor's *** analyses of the initial and optimized output characteristics were conducted,focusing on the effects of the isometric radius coefficient and overflow area on the motor's *** indicate that the optimized motor's overflow area increased by 6.9%,while its rotational speed reduced by 6.58%.The torque,as tested by Infocus,saw substantial improvements of38.8%.This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology.

关键词： Positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area

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Zircon U-Pb Ages and Tectonic Implications of Late Paleozoic Volcanic Rocks in the Western Tianshan,North Xinjiang,China

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Journal of earth Science 2022年第3期33卷 736-752页

作者： Zaili Tao Jiyuan Yin Wen Chen Yuelong Chen Jingbo Sun Zhihua Xu School of earth Sciences and resources China University of GeosciencesBeijing 100083China key laboratory of deep-earth dynamics of ministry of natural resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Limited Liability Company TBEA DUSHANBE Mining IndustryChangji 831100China

The Late Paleozoic volcanic rocks are widespread in the Western Tianshan,and mainly consist of basalt,trachyte,trachy-andesite,andesite and ***,the formation timing and tectonic implications of the volcanic rocks remain *** obtain a comprehensive dataset with adequate spatial coverage,we collected the published zircon U-Pb age data of the Late Paleozoic volcanic rocks in the Western Tianshan,and mapped the temporal and spatial distribution of these volcanic *** compiled dataset indicates that the volcanic rocks in the Western Tianshan were formed in two major stages:Late Silurian-Early Carboniferous and Late Carboniferous-Middle *** southward subduction of the Northern Tianshan Ocean formed a large number of Late Silurian-Early Carboniferous volcanic *** flare-up of Late Carboniferous to Middle Permian magmatism in the NTOB was considered to be the response of the slab-roll back of the northern Tianshan ***,arc magma assemblage and spatial-temporal distribution are of great significance to identify the dynamic mechanism transformation of subduction zone.

关键词： volcanic rocks zircon Western Tianshan tectonic transformation slab-roll back

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Origin of Chromitites in the Songshugou Peridotite Massif,Qinling Orogen (Central China): Mineralogical and Geochemical Evidence

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Journal of earth Science 2019年第3期30卷 476-493页

作者： Huichao Rui Jiangang Jiao Mingzhe Xia Jingsui Yang Zhaode Xia School of earth Sciences China University of Geosciences Wuhan 430074 China key Laboratoiy of deep-earth dynamics of ministry of natural resources Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China School of earth Science and resources Chang'an University Xi'an 710054 China

The Songshugou peridotite massif is located in the north of Shangdan suture zone, North Qinling orogenic belt of Central China. The massif is mainly composed of fine-grained mylonitic dunites, coarse-grained dunites, fine- and coarse-grained harzburgites, and minor clinopyroxenites. The coarsegrained dunites as well as parts of the harzburgites host small-scale chromitites? Chromite grains from various textural types of chromitites and dunites pervasively contain primary and secondary silicate inelusions. Primary inclusions are dominated by monophase olivine, with minor clinopyroxene and a few multiphase mineral assemblages consisting of olivine and clinopyroxene. Secondary inclusions, mainly Cr-chlorite and tremolite, show irregular crystal shapes. Besides, Cr2O3 contents (0.08 wt.%-0.71 wt.%) of primary olivine inclusions are remarkably higher than those of interstitial olivine (<0.1 wt.%). Chr0- mites in the Songshugou peridotite massif are high-Cr type, with Cr^# and Mg^# values ranging of 67.5-87.6, and 23.4-41.2, respectively. The Cr-chlorite, formed by reactions between olivine and chromite in the presence of fluid under middle temperature, indicates the Songshugou peridotite massif has undergone alteration/metamorphism process during emplacement. Chromite grains are modified by these processes, resulting in the various degrees of enrichment of Fe2O3, Cr2O3, Zn, Co and Mn, depletion of MgO, A12O3,Ga, Ti and Ni. Due to low silicate/chromite ratios in the massive ores, chromites from them are slightly influenced by alteration/metamorphism and thus preserve the pristine magmatic compositions. The parental magma calculated based on them has 11.17 wt.%-13.57 wt.% A12O3 and 0.15 wt.%-0.27 wt.% TiO2, which is similar to the parental melts of high-Cr chromitites from elsewhere and comparable with those of boninites. Combined with informations from previous studies, major and trace elements geochemistry of chromite, as well as the nature of the parental magma, it can

关键词： peridotite chromitite chromite trace element parental magma Songshugou Qinling Orogen

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Transient Fluvial Incision in the Central Segment of the Lancang River Orogenic Belt,Yunnan Province,SW China

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1728-1730页

作者： SHI Xiaohui LI Tingting PEI Lixin WANG Qingtao HUI Bo CHENG Chao State key laboratory of Continental dynamics Department of GeologyNorthwest UniversityXi’an 710069China key laboratory of deep-earth dynamics of ministry of natural resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Chengji Middle School Jingning CountyPingliangGansu 743409China

Objective Geomorphology has played a central role in the study of active orogenic *** tectonic deformation associated with the collision of the Indian and Eurasian plates has occurred in the southeastern margin of the... 详细信息

关键词： Eurasian southeastern Plateau

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Interannual variations in salt flux at 80°E section of the equatorial Indian Ocean

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Science China earth Sciences 2023年第9期66卷 2142-2161页

作者： Cuncun XIE Ruibin DING Jiliang XUAN Daji HUANG State key laboratory of Satellite Ocean Environment dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Guangxi key laboratory of Beibu Gulf Marine resources Environment and Sustainable DevelopmentFourth Institute of OceanographyMinistry of Natural ResourcesBeihai 536015China Institute of Polar and Ocean Technology Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

The interannual variations in salt flux on the 80°E section in the equatorial Indian Ocean were explored based on the ORAS5 data,which was quite consistent with the observational data among the four available reanalysis *** results indicated that the area with significant interannual variations in salt flux coincided with that of significant climatological mean salt flux in general and was mainly located in the upper 150 m ***,three important areas were identified in the north-south direction,i.e.,(1)the Equatorial Indian Ocean Area(EIOA,3°S–3°N),where the mean salt flux was eastward with the largest value on the section and associated with the most significant interannual variations mainly modulated by the Wyrtki Jets and the Equatorial Undercurrent;(2)the South Equatorial Indian Ocean Area(SEIOA,3°S–6°S),where the mean salt flux changed in the vertical direction from strong eastward flux in the upper layer to weak westward flux in the subsurface layer and associated with significant interannual variations in the upper 100 m layer,which was affected by the South Equatorial Countercurrent;and(3)the North Equatorial Indian Ocean Area(NEIOA,3°N–6°N),where the mean salt flux changed in the north-south direction from strong westward flux to the north of 5°N to weak eastward flux in the south and associated with relatively significant interannual variations,which was mainly influenced by the South Sri Lanka Coastal *** leading interannual variation modes were revealed by the empirical orthogonal function *** first mode accounted for 39%of the total variance and had four significant spatial antinodes;two of those in-phase antinodes were located at SEIOA and upper 75 m of EIOA,and the other two opposite in-phase antinodes were located at NEIOA and below 75 m of *** second mode accounted for 17%of the total variance having four antinodes with two dominant out-of-phase antinodes located at the subsurface of EIOA and ***

关键词： Salt flux Interannual variation 80°E section Equatorial Indian Ocean Current

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Salinity fronts shape spatial patterns in zooplankton distribution in Hangzhou Bay

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Acta Oceanologica Sinica 2024年第6期43卷 96-106页

作者： Yepeng Xu Yiqi Wang Lin Zhan Yijun Ou Kangning Jia Ming Mao Xuyu Zhu Zhibing Jiang Yuanli Zhu Wei Huang Ping Du Jiangning Zeng Lu Shou Feng Zhou key laboratory of Marine Ecosystem dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China key laboratory of Nearshore Engineering Environment and Ecological Security of Zhejiang Province Hangzhou 310012China State key laboratory of Satellite Ocean Environment dynamics Ministry of Natural ResourcesHangzhou 310012China Nantong Marine Environmental Monitoring Center Ministry of Natural ResourcesNantong 226002China key laboratory of Ocean Space Resource Management Technology Ministry of Natural ResourcesHangzhou 310012China Observation and Research Station of Marine Ecosystem in the Yangtze River Delta Ministry of Natural ResourcesZhoushan 316021China

Ocean fronts play important roles in nutrient transport and in the shaping ecological *** zones in small bays are typically small in scale,have a complex structure,and they are spatially and temporally variable,but there are limited data on how biological communities respond to this *** Bay,a mediumsized estuary in China,is an ideal place in which to study the response of plankton to small-scale ocean fronts,because three water masses(Qiantang River Diluted Water,Changjiang River Diluted Water,and the East China Sea current) converge here and form dynamic salinity fronts throughout the *** investigate zooplankton communities,and temperature,salinity and chlorophyll a(Chl a) in Hangzhou Bay in June(wet perio d) and December(dry period) of 2022 and examine the dominant environmental factors that affect zooplankton community spatial *** then match the spatial distributions of zooplankton communities with those of salinity fronts.S alinity is the most important explanatory variable to affect zooplankton community spatial variability during both wet and dry periods,in that it contributes>60% of the variability in community ***,the spatial distributions of zooplankton match well with salinity *** December,with weaker Qiantang River Diluted Water and a stronger secondary Changjiang River Plume,zooplankton communities occur in moderate salinity(MS,salinity range 15.6±2.2) and high salinity(HS,22.4±1.7) regions,and their ecological boundaries closely match the Qiantang River Diluted Water *** June,different zooplankton communities occur in low salinity(LS,3.9±1.0),MS(11.7±3.6) and HS(21.3±1.9) *** the LS region occurs abnormally in the central bay rather than its apex because of the anomalous influence of rising and falling tides during the sampling perio d,the ecological boundaries still match salinity ***-salinity or brackish-water zooplankter taxa are relatively more abunda

关键词： zooplankton spatial distribution salinity fronts Hangzhou Bay

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Discrepant chemical differentiation and magmatic-hydrothermal evolution of high-silica magmatism associated with Pb–Zn and W mineralization in the Lhasa terrane

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Geoscience Frontiers 2022年第5期13卷 32-49页

作者： Shunbao Gao Xin Chen Youye Zheng Nan Chao Shunli Zheng Hao Lin Xiaojia Jiang Song Wu Institute of Geological Survey China University of GeosciencesWuhan 430074China State key laboratory of Geological Processes and Mineral resources School of Earth ResourcesChina University of GeosciencesWuhan 430074China key laboratory of deep–earth dynamics of ministry of natural resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China School of earth Sciences and resources China University of GeosciencesBeijing 100083China

High-silica(SiO_(2)>70 wt.%)granites(HSGs)are the main source of W,Sn,and rare ***,abundant HSGs,temporally,spatially,and genetically associated with Pb-Zn mineralization,in the Lhasa terrane(LT),provided an ideal opportunity to study the key factors responsible for Pb-Zn enrichment,instead of W-Sn *** we contribute to this topic through U-Pb dating of zircon and garnet,and whole-rock and Sr-Nd-Hf isotopic geochemistry of ore-related quartz porphyries in the Bangbule deposit and compared these results with published data from large and giant Pb-Zn and W deposits in the *** magmatism-alteration-mineralization event in the Bangbule deposit was recorded by robust zircon U-Pb ages of 77.3±0.9 Ma and hydrothermal garnet U-Pb ages of 75.7±4.8 Ma,which is 10-15 Ma earlier than the main Paleocene metallogenic event and the first record of late Cretaceous Pb-Zn polymetallic mineralization in the *** late Cretaceous-Paleocene magmatism and mineralization events are a response to the subduction of Neotethyan oceanic lithosphere,which occurred as a result of the collision of the Indian and Asian *** HSGs related to Pb-Zn mineralization,with high totalalkalis and low magnesian contents,are enriched in Ba,Th,and Rb,but depleted in Ti,Eu,Sr,and *** belong to either the S-type,or I-type *** Sr-Nd-Hf isotopic compositions of the Pb-Zn mineralized granites demonstrate that they were generated by the partial melting of Proterozoic basement with or without mantle-derived melt *** was consistent with the postulated source of W enrichment in the *** Pb-Zn and W related granites have similar zircon-Ti-saturation temperatures,comparable low whole-rock Fe_(2)O_(3)/FeO ratios,and zircon oxygen *** indicated that the Pb-Zn-W enrichment in the high-silica magma system could be attributed to a relatively reduced *** Pb-Zn related HSGs,abundant quartz and feldspar phenocrysts,and weak fractionation of twin-elements in wh

关键词： High-silica granites(HSGs) Magmatic-hydrothermal evolution Regional metallogeny Bangbule Southern China

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LA-ICP-MS Zircon U-Pb Age and Hf Isotopic Composition of Late Carboniferous Granodiorite in the Southern East Junggar,Xinjiang:Genesis and Tectonic Implication

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Acta Geologica Sinica(English Edition) 2019年第S1期93卷 140-141页

作者： SONG Peng WANG Tao TONG Ying key laboratory of deep-earth dynamics of ministry of natural resources Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Beijing SHRIMP Center Beijing 100037China

A large area of Late Paleozoic intrusions occursalong the Kalamaili fault in North Xinjiang,which is divided into I-type and A-type granite(Liu et al.,2013),and are the ideal objects for revealing the geological evolu... 详细信息

关键词： zircon U-Pb age Hf isotopic composition granodiorite East Junggar continental growth

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