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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1163-1164页

作者： GONG Hujun ZHANG Rui ZHANG Yunxiang YUE Leping institute of Cenozoic geology and Environment State Key Laboratory of Continental DynamicsDepartment of GeologyNorthwest University

Objective Aeolian sediments on the Chinese Loess Plateau contain some of the best continental archives of palaeoclimate change in the Late Cenozoic. The consensus that alternating MS in loess-paleosols in China was due to the strengthening and weakening of the East Asian palaeomonsoon provides an excellent climate record when correlated with global ice volume. Significantly, new basal dates from the red clay underlying the loess-paleosol sequence indicate that wind-blown dust began to accumulate on the Chinese Loess Plateau at least 22 million years ago. There are differences of opinion,

关键词： ODP MS of from on A New Model for Correlation between the Marine Benthic Oxygen Isotope and Red Clay Magnetic Susceptibility on the Chinese Loess Plateau for

Paleomagnetic results from Late Carboniferous to early Permian rocks in the northern Qiangtang terrane, Tibet, China, and their tectonic implications

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Science China Earth Sciences 2017年第1期60卷 124-134页

作者： YANG XingFeng CHENG Xin ZHOU YaNan MA Lun ZHANG XiaoDong YAN ZhaoSheng PENG XiMing SU HaiLun WU HanNing department of geology and state key laboratory of continental dynamics Northwest University Xi 'an 710069 China

Results of a systematic paleomagnetic study are reported based on Late Carboniferous to early Permian sedimentary rocks on the north slope of the Tanggula Mountains,in the northern Qiangtang terrane(NQT),Tibet,*** revealed that magnetic minerals in limestone samples from the Zarigen Formation(CP^z)are primarily composed of magnetite,while those in sandstone samples from the Nuoribagaribao Formation(Pnr)are dominated by hematite alone,or hematite and magnetite in *** thermal,or alternating field,demagnetization allowed us to isolate a stable high temperature component(HTC)in 127 specimens from 16 sites which successfully passed the conglomerate test,consistent with primary *** tilt-corrected mean direction for Late Carboniferous to early Permian rocks in the northern Qiangtang terrane is D_s=30.2°,I_s=-40.9°,k_s=269.0,a_(95)=2.3°,N=16,which yields a corresponding paleomagnetic pole at 25.7°N,241.5°E(dp/dm=2.8°/1.7°),and a paleolatitude of 23.4°*** results,together with previously reported paleomagnetic data,indicate that:(1)the NQT in Tibet,China,was located at a low latitude in the southern hemisphere,and may have belonged to the northern margin of Gondwana during the Late Carboniferous to early Permian;(2)the Paleo-Tethys Ocean was large during the Late Carboniferous to early Permian,and(3)the NQT subsequently moved rapidly northwards,perhaps related to the fact that the Paleo-Tethys Ocean was rapidly contracting from the Late Permian to Late Triassic while the Bangong Lake-Nujiang Ocean,the northern branch of the Neo-Tethys Ocean,expanded rapidly during this time.

关键词：北 Qiangtang 岩层晚含碳早二叠摇磁力集团企业测试 Paleomagnetic 杆

Devonian continental arc magmatism in the southern Central Asian Orogenic Belt:Evidence from the Dunhuang Block,NW China

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Geoscience Frontiers 2023年第6期14卷 155-169页

作者： Baoping Gan Juxing Tang Inna Safonova Limao Qin Chunrong Diwu Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China state key laboratory of continental dynamics Department of GeologyNorthwest UniversityXi’an 710069China MNR key laboratory of Metallogeny and Mineral Resource Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Sobolev institute of geology and Mineralogy SB RAS Koptyuga ave.3Novosibirsk 630090Russia

Reconstruction of periods and sources of continental arc magmatism provides critical insights for deciphering the thermal evolution and geodynamics of the continental lithosphere and unveiling subduction-related episodes of accretion and *** Dunhuang Block,located in the southern Central Asian Orogenic Belt,is built upon a Precambrian metamorphic crystalline basement that is intruded by numerous Paleozoic *** this paper,we present new zircon U-Pb ages,wholerock geochemistry and Sr-Nd-Pb-Hf isotopes from the Hanxiakouzi and Shuangta granodiorite plutons outcropped in the central and northern Dunhuang Block,*** U-Pb zircon dating indicate that the Hanxiakouzi and Shuangta granodiorites were emplaced at ca.366–363 Ma,i.e.,in the late ***,the Hanxiakouzi granodiorites are medium-to high-K,I-type granites possessing high Sr and Sr/Y,i.e.,similar to *** Hanxiakouzi granodiorites show negativeε_(Nd)(t)values(-8.2 to-6.6),significant positive eHf(t)values(+0.7 to+8.1),and evolved Pb isotope features suggesting their derivation by melting of subducted terrigenous sediments,interaction of melts with mantle peridotite,and assimilation of ancient crust during magma *** Shuangta granodiorites belong to high-K calc-alkaline I-type granites with medium Sr and low Sr/*** Shuangta granodiorites yield negativeε_(Nd)(t)values(-2.9 to-3.1)and negative to positive zircon eHf(t)values(-1.8 to+3.6),suggesting their formation by partial melting of ancient mafic crust with addition of minor mantle-derived melt and subducted terrigenous *** general,Hf-in-zircon isotopes characteristics of the late Paleozoic granitic rocks in the Dunhuang Block indicate that the southern Dunhuang area carries more ancient crust materials than the central and northern Dunhuang areas,indicating a lateral heterogeneity of the middle Paleozoic ***,the middle Paleozoic granitoids of the Dunhuang Block were emplaced at an ac

关键词： Devonian granitoids Hf-in-zircon isotopes Sr-Nd-Pb isotopes Subducted sediments Active continental margin

The Discovery of Late Ordovician Granodiorite in the Xiemisitai Area, Xinjiang and its Geological Significance

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2327-2329页

作者： WANG Juli HU Yang WANG Jianqi WANG Min state key laboratory of continental dynamics Department of GeologyNorthwest University

Objective The Xiemisitai area located in the northern part of the West Junggar, Xinjiang is an important component of the central Asian metallogenic domain. Recent studies show that the formation age of acid volcanic and intrusive rocks in the Xiemisitai area mainly ranges from the Late Silurian to the early Devonian, and the age of the mineralized dacite porphyry is early Silurian. These rocks are the principal part of the early Paleozoic arc magmatic belt, which are related to the Paleo-Asian Ocean slab subduction. However, there have been no reports of the pre-Silurian arc granitoid, which has restricted the discussion on the early Paleozoic tectonic evolution in the area. This work studied the newly discovered granodiorite mass near Yinisala in the Xiemisitai area to determine its formation age and tectonic environment, magma source and petrogenesis, providing new information for the discussion on the early Paleozoic tectonic evolution in the Xiemisitai area.

关键词： The Discovery of Late Ordovician Granodiorite

Mesozoic Tectonothermal Evolution of the Southern Central Asian Orogenic Belt: Evidence from Apatite Fission-Track Thermochronology in Shalazha Mountain, Inner Mongolia

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Journal of Earth Science 2023年第1期34卷 37-53页

作者： Heng Peng Jianqiang Wang Chiyang Liu Shaohua Zhang Yazhuo Niu Tianbing Zhang Bo Song Wei Han state key laboratory of continental dynamics Department of GeologyNorthwest UniversityXi’an710069China School of Earth Sciences and Engineering Xi’an Shiyou UniversityXi’an710065China Xi’an Center of Geological Survey China Geological SurveyXi’an710054China

Mesozoic intracontinental orogeny and deformation were widespread within the southern Central Asian Orogenic Belt(CAOB). Chronological constraints remain unclear when assessing the Mesozoic evolution of the central segment of this region. The tectonic belt of Shalazha Mountain located in the center of this region is an ideal place to decode the deformation process. Apatite fission-track(AFT) thermochronology in Shalazha Mountain is applied to constrain the Mesozoic tectonothermal evolution of the central segment of southern CAOB. The bedrock AFT ages range from 161.8 ± 6.9 to 137.0 ± 7.3 Ma, and the first reported detrital AFT obtained from Lower Cretaceous strata shows three age peaks: P1(ca. 178 Ma), P2(ca. 149 Ma) and P3(ca. 105.6 Ma). Bedrock thermal history modeling indicates that Shalazha Mountain have experienced three stages of differential cooling: Late Triassic–early Jurassic(~230–174 Ma), Late Jurassic–Earliest Cretaceous(~174–135 Ma) and later(~135 Ma). The first two cooling stages are well preserved by the detrital AFT thermochronological result(P1, P2) from the adjacent Lower Cretaceous strata, while P3(ca. 105.6 Ma) records coeval volcanic activity. Furthermore, our data uncover that hanging wall samples cooled faster between the Late Triassic and the early Cretaceous than those from the footwall of Shalazha thrust fault, which synchronizes with the cooling of the Shalazha Mountain and implies significant two-stage thrust fault activation between ca. 230 and 135 Ma. These new low-temperature thermochronological results from the Shalazha Mountain region and nearby reveal three main phases of differential tectonothermal events representing the Mesozoic reactivation of the central segment of the southern CAOB. In our interpretations, the initial rapid uplift in the Late Triassic was possibly associated with intracontinental orogenesis of the CAOB. Subsequent Middle Jurassic–Earliest Cretaceous cooling is highly consistent with the Mesozoic intense intrap

关键词： intracontinental deformation Shalazha Mountain southern Central Asian Orogenic Belt apatite apatite fission-track thermal history modeling exhumation

The Major Two-stage Shortening Deformation of the Northern Tibet and Tian Shan Area Since the Latest Oligocene

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Acta Geologica Sinica(English Edition) 2015年第5期89卷 1546-1560页

作者： LU Haijian LI Haibing LIU Dongliang state key laboratory of continental Tectonics and dynamics Institute of Geology Chinese Academy of Geological Sciences

It seems to be progressively recognized that the stress of the India-Asia convergent front can be transferred rapidly through the southern and central Tibetan lithosphere to the northern Tibet, hence leading to the crustal thickening deformation there during or immediately after the onset of the India-Asia collision（ca.55 Ma）.This study focuses on the late Cenozoic deformation and tectonic uplift of the northern Tibet and Tian Shan *** compilations of a variety of proxy data from sediments and bedrocks suggest that the northern Tibet and Tian Shan area underwent one stage of approximately synchronous widespread contractile deformation since 25–20 Ma, which seemed to decrease at circa 18 Ma as revealed by low-temperature thermochronological *** latest Oligocene-early Miocene was also significant basin-forming episodes when many intermontane subbasins began to receive syntectonic sedimentation in the northeastern ***, the other phase of compressional deformation began to encroach more widely into the northern Tibet and Tian Shan area in episodic steps or continuously from 16–12 Ma to present.

关键词： shortening deformation the northern Tibet the Tian Shan area the latest Oligocene

early Jurassic Soft-Sediment Deformation Interpreted as Seismites in the Wuqia Pull-Apart Basin and the Strike-Slip Talas-Ferghana Fault, Xinjiang, China

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 730-737页

作者： QIAO Xiufu GUO Xianpu state key laboratory of continental Tectonics and dynamics institute of geology Chinese Academy of Geological Sciences

The early Jurassic soft-sediment deformation occurring within lacustrine sandstone is distributed mainly in the Wuqia region of SW Tianshan Mountains, Xinjiang, western China. Triggered by earthquakes, such deformation was found to occur in three beds overlying the lower Jurassic Kangsu Formation. The main styles of deformation structures comprise load cast, ball-and- pillow, droplet, cusps, homogeneous layer, and liquefied unconformity. The deformation layers reflect a series of three strong earthquakes at the end of early Jurassic in the Wuqia region. The differences of deformation mechanisms undergone might represent the varying magnitudes of the earthquake events. During the early Jurassic, the Wuqia region was located in a pull-apart basin controlled by the significant Talas-Ferghana strike-slip fault in central Asia, which initiated the soft-sediment deformation induced by earthquakes. Our research suggests that the paleoseismic magnitudes could have ranged from Ms 6.5 to 7.

关键词： early Jurassic seismicity load droplet liquefied unconformity Talas-Ferghana fault Xinjiang

A Novel Method to Enhance the Inversion Speed and Precision of the NMR T_(2) Spectrum by the TSVD Based Linearized Bregman Iteration

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2451-2463页

作者： Yiguo Chen Congjun Feng Yonghong He Zhijun Chen Xiaowei Fan Chao Wang Xinmin Ge state key laboratory of continental dynamics Northwest UniversityXi’an710069China department of geology Northwest UniversityXi’an710069China Reseach institute of Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi’an710075China School of Geosciences China University of PetroleumQingdao266580China

The low-field nuclear magnetic resonance(NMR)technique has been used to probe the pore size distribution and the fluid composition in geophysical prospecting and related ***,the speed and accuracy of the existing numerical inversion methods are still challenging due to the ill-posed nature of the first kind Fredholm integral equation and the contamination of the *** paper proposes a novel inversion algorithmto accelerate the convergence and enhance the precision using empirical truncated singular value decompositions(TSVD)and the linearized Bregman *** L1 penalty term is applied to construct the objective function,and then the linearized Bregman iteration is utilized to obtain fast *** reduce the complexity of the computation,empirical TSVD is proposed to compress the kernel matrix and determine the appropriate truncated *** novel inversion method is validated using numerical *** results indicate that the proposed novel method is significantly efficient and can achieve quick and effective data solutions with low signal-to-noise ratios.

关键词： Low field nuclear magnetic resonance linearized bregman iteration truncated singular value decomposition numerical simulations

Sedimentary fill history of the Huicheng Basin in the West Qinling Mountains and associated constraints on Mesozoic intracontinental tectonic evolution

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Science China Earth Sciences 2013年第5期56卷 1639-1653页

作者： LI Wei DONG YunPeng GUO AnLin LIU XiaoMing LIU YiQun ZHA XianFeng ZHANG KuaiLe state key laboratory of continental dynamics Department of GeologyNorthwest University Xi'an Center of Geological Survey China Geological Survey

The Qinling Orogenic Belt is divided commonly by the Fengxian-Taibai strike-slip shear zone and the Huicheng Basin into the East and West Qinling mountains,which show significant geological differences after the Indosinian *** Fengxian-Taibai fault zone and the Meso-Cenozoic Huicheng Basin,situated at the boundary of the East and West Qinling,provide a natural laboratory for tectonic analysis and sedimentological study of intracontinental tectonic evolution of the Qinling Orogenic *** order to explain the dynamic development of the Huicheng Basin and elucidate its post-orogenic tectonic evolution at the junction of the East and West Qinling,we studied the geometry and kinematics of fault zones between the blocks of West Qinling,as well as the sedimentary fill history of the Huicheng ***,we found that after the collisional orogeny in the Late Triassic,post-orogenic extensional collapse occurred in the early and Middle Jurassic within the Qinling Orogenic Belt,resulting in a series of rift ***,in the Late Jurassic and early Cretaceous,a NE-SW compressive stress field caused large-scale sinistral strike-slip faults in the Qinling Orogenic Belt,causing intracontinental escape tectonics at the junction of the East and West Qinling,including eastward finite escape of the East Qinling micro-plate and southwest lateral escape of the Bikou ***,the strike-slip-related early Cretaceous sedimentary basin was formed with a right-order echelon arrangement in sinistral shear zones along the southern margin of the Huicheng *** during the Mesozoic,the Huicheng Basin and surrounding areas experienced four tectonic evolutionary stages,including extensional rift basin development in the early and Middle Jurassic,intense compressive uplift in the Late Jurassic,formation of a strike-slip extensional basin in the early Cretaceous,and compressive uplift in the Late Cretaceous.

关键词：中新生代盆地构造演化沉积充填西秦岭中生代相关约束陆内历史

Provenance of the early Permian bauxitic claystone in Huayingshan region,Sichuan Basin,South China:Constraints from U-Pb ages and trace elements of detrital zircons

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Journal of Palaeogeography 2023年第2期12卷 211-228页

作者： Tian-Jia Liu Xun-Lian Wang Zhen-Tao Wang Xi-Fang Liu Peng-Cheng Ju Jia-Ai Zhong School of the Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China key laboratory of Metallogeny and Mineral Resources Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China state key laboratory of continental dynamics Department of GeologyNorthwest UniversityXi'an 710069Shaanxi ProvinceChina 405 Geological Brigade of Sichuan Bureau of geology and Mineral Resources Dujiangyan 611830Sichuan ProvinceChina

The early Permian bauxite in the Sichuan Basin is an important part of karst-type bauxite deposits in South China Block and its provenance is poorly *** we present results of mineralogy,wholerock geochemistry,detrital zircon U-Pb ages and trace element compositions of the bauxitic claystone from the Lower Permian Dazhuyuan Formation and those of the siltstone from the underlying Lower Silurian Hanjiadian Formation in Huayingshan region,Sichuan Basin,South China Block to constrain the provenance of the bauxitic *** zircons from bauxitic claystone and siltstone have similar age spectra,and the ages of bauxitic claystone are classified into five groups of 2600-2200 Ma,1800-1600 Ma,1200-900 Ma,900-650 Ma,and 650-400 Ma *** of the siltstone are classified into four groups of 2600-2200 Ma,1200-900 Ma,900-650 Ma,and 650-400 Ma *** propose that the bauxitic claystone in the study region has mixed sources:the siltstone of the Lower Silurian Hanjiadian Formation probably constitutes the dominant source,and the Late Paleoproterozoic magmatic rocks along the western margin of the Yangtze Block are probably the secondary ***,the source materials of the Hanjiadian Formation siltstone are mainly sourced from Grenville-aged magmatic rocks in the Cathaysia Block and Neoproterozoic magmatic rocks in the Jiangnan orogen,with minor contributions from the underlying clastic sediments in the Cathaysia Block and Pan-African magmatic rocks in the orogen in eastern Gondwana.

关键词： Huayingshan Dazhuyuan Formation Bauxitic claystone Detrital zircon Mixed sources