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Acta Geologica Sinica(English Edition) 2009年第5期83卷 884-892页

作者： Azam SOLTANMOHAMMADI Mohammad RAHGOSHAY Morteza KHALATBARI-JAFARI Faculty of earth sciences Shahid Beheshti University TehranIran institute for earth sciences Geological Survey of IranTehranIran

The Late Cretaceous Khabr-Marvast tectonized ophiolite is located in the middle part of the Nain-Baft ophiolite belt, at the south-western edge of the central iranian microcontinent. Although all the volcanic rocks in the study area indicate subduction-related magmatism （e.g. high LILE （large ion lithophile elements） / HFSE （high field strenght elements） ratios and negative anomalies in Nb and Ta）, geological and geochemical data clearly distinguish two distinct groups of volcanic rocks in the tectonized association：（1） group 1 is comprised of hyaloclastic breccias, basaltic pillow lavas, and andesite sheet flows. These rocks represent the Nain-Baft oceanic crust; and （2） group 2 is alkaline lavas from the top section of the ophiolite suite. These lavas show shoshonite affinity, but do not support the propensity of ophiolite.

关键词： alkaline lavas subduction-related magmatism tectonized ophiolite central iranian microcontinent

Tectonic Nature of the Northern Segment of the Jiao-Liao-Ji Belt:A Rift or Continental Collision Belt?

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1159-1160页

作者： MENG En WANG Chaoyang LI Yanguang CAI Jia YANG Hong LI Zhuang institute of Geology Chinese Academy of Geological Sciences Xi'an Center of geological survey China Geological Survey School of earth and Space sciences Peking University

Objective The tectonic characteristics and evolution of the Paleoproterozoic Jiao-Liao-Ji belt have been extensively studied in recent decades （Fig. 1 a）. Two main models have been proposed for the formation of this belt： a continental-or arc-continent collisional belt, and the opening and closure of an intra-continental rift. The main reasons for these ongoing debates are own to the complex composition, including metamorphosed volcano-sedimentary rocks, multiple pulses of granitic magmatism, meta-mafic intrusions, and tectono- metamorphic history. In addition, earlier work focused on the geochronology and metamorphic evolution, whereas the source properties, petrogenesis, and tectonic setting of the metamorphosed volcano-sedimentary sequence and meta- mafic intrusions are poorly understood.

关键词： of in as with Ga Tectonic Nature of the Northern Segment of the Jiao-Liao-Ji Belt:A Rift or Continental Collision Belt were meta or

The Cu-Mo Mineralization of the Late Jurassic Porphyry in the Northern Great Xing'an Range: Constraints from Zircon U-Pb Ages of the Ore-Causative Granites

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 236-237页

作者： DENG Changzhou LI Guanghui College of earth sciences Jilin University Heilongjiang institute of geological survey

The Great Xing’an Range(GXAR)is one of the most important metallogenic belts in *** study has shown that porphyry Cu-Mo deposit distributed in the northern Great Xing’an Range formed mainly in two stages:(1)Early Ordovician,such as Duobaoshan and Tongshan deposits(Liu et al.,2017);2)Triassic-Early Jurassic,including Wunugetushan,Taipingchuan and Badaguan deposits(Tang et al.,2016).In recent years,two potential porphyry Cu-Mo deposits,Huoluotai and Xiaokele,were discovered in the Erguna Block,northern GXAR(Figs.1a–b).However,the ore formation ages and regional metallogenic regularity are ambiguous due to the lack of isotopic *** zircon U-Pb ages from the ore-causative granites were reported in this paper,with the aims to constrain the metallogenic ages and provide evidence for study of the regional metallogenic regularity and ore prospect prediction.

关键词： The Great Xing’an Range(GXAR) granites Cu-Mo

Oligocene subduction-related plutonism in the Nodoushan area,Urumieh-Dokhtar magmatic belt: Petrogenetic constraints from U-Pb zircon geochronology and isotope geochemistry

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Geoscience Frontiers 2019年第2期10卷 725-751页

作者： Badieh Shahsavari Alavijeh Nematollah Rashidnejad-Omran Fatma Toksoy-K?ksal Wenliang Xu Jalil Ghalamghash Department of Geology Faculty of Basic SciencesTarbiat Modares University Department of geological Engineering Middle East Technical University College of earth sciences Jilin University State Key Laboratory of geological Processes and Mineral Resources China University of Geosciences research institute for earth sciences Geological Survey of Iran

Geochemical data and Sr-Nd isotopes of the host rocks and magmatic microgranular enclaves(MMEs)collected from the Oligocene Nodoushan Plutonic Complex(NPC) in the central part of the Urumieh-Dokhtar Magmatic Belt(UDMB) were studied in order to better understand the magmatic and geodynamic evolution of the UDMB. New U-Pb zircon ages reveal that the NPC was assembled incrementally over ca. 5 m.y., during two main episodes at 30.52 ± 0.11 Ma and 30.06 ± 0.10 Ma in the early Oligocene(middle Rupelian) for dioritic and granite intrusives, and at 24.994 ± 0.037 Ma and 24.13 ± 0.19 Ma in the late Oligocene(latest Chattian) for granodioritic and diorite porphyry units,respectively. The spherical to ellipsoidal enclaves are composed of diorite to monzodiorite and minor gabbroic diorite(SiO_2 = 47.73-57.36 wt.%; Mg# = 42.15-53.04); the host intrusions are mainly granite,granodiorite and diorite porphyry(SiO_2 = 56.51-72.35 wt.%; Mg# = 26.29-50.86). All the samples used in this study have similar geochemical features, including enrichment in large ion lithophile elements(LILEs, e.g. Rb, Ba, Sr) and light rare earth elements(LREEs) relative to high field strength elements(HFSEs) and heavy rare earth elements(HREEs). These features, combined with a relative depletion in Nb,Ta, Ti and P, are characteristic of subduction-related magmas. Isotopic data for the host rocks display ISr = 0.705045-0.707959, εNd(t) =-3.23 to +3.80, and the Nd model ages(TDM) vary from 0.58 Ga to 1.37 Ga. Compared with the host rocks, the MMEs are relatively homogeneous in isotopic composition,with Isr ranging from 0.705513 to 0.707275 and εNd(t) from -1.46 to 4.62. The MMEs have TDM ranging from 0.49 Ga to 1.39 Ga. Geochemical and isotopic similarities between the MMEs and their host rocks demonstrate that the enclaves have mixed origins and were most probably formed by interactions between the lower crust-and mantle-derived magmas. Geochemical data, in combination with geodynamic evidence, suggest that

关键词： Urumiehe-Dokhtar magmatic belt Granitoid rocks Subduction Zircon U-Pb ages Radiogenic isotopes Central iran

Evaluation of Slip Rate on Astara Fault System, North iran

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Journal of earth Science 2016年第6期27卷 971-980页

作者： Amir Barzegari Rasoul Esmaeili Mohammad Ebrahimi Ali Faghih Manucher Ghorashi Hamid Nazari Depatment of Geology Faculty of SciencesIslamic Azad University North Tehran BranchTehran ***Iran State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of sciences Beijing 100049China Department of Geology Faculty of SciencesUniversity of ZanjanZanjan ***Iran Department of earth sciences College of SciencesShiraz UniversityShiraz 71454Iran geological survey of iran Tehran 131851494Iran research institute for earth sciences Geological Survey of lranTehran 131851494Iran

Due to its strategic location, the Astara fault system （AFS）, which is located in iran, has given rise to a number of earthquakes. In spite of its frequent seismic events, limited information is available for AFS. Slip rate is one of the important variables for future scrutiny of seismic risk of this fault system. The main objective of this research is to study slip rates at intermediate and short terms for this fault system using geological, geodetic observations and empirical method. Using the geological data, the intermediate-term horizontal and vertical slip rates for AFS have been determined to be 2.8±0.2 and 0.27±0.03 mm/year, respectively. In addition, the short-term slip rates of the fault, based on the geodetic method （using displacement values of two GPS stations： HASH and DAMO） and assuming attenuation of 60% （to fold the sediment of South Caspian Basin and shortening of Talesh Mountain range）, determined to be 1.23±0.03 and 2.05±0.05 mm/year for the horizontal and vertical slips, respectively. Finally, evaluation of the slip rate using empirical relationship yields 10 mm/year for the entire fault system, which seems rather implausible.

关键词： Astara fault system intermediate slip rate geodetic slip rate empirical slip rate Gutenberg-Richter method focal depth.

Resource prediction and assessment based on 3D/4D big data modeling and deep integration in key ore districts of North China

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Science China earth sciences 2021年第9期64卷 1590-1606页

作者： Gongwen WANG Zhiqiang ZHANG Ruixi LI Junjian LI Deming SHA Qingdong ZENG Zhenshan PANG Dapeng LI Leilei HUANG School of earth sciences and Resources China University of Geosciences(Beijing)Beijing100083China Tianjin geological survey Center of China geological survey Tianjin300170China Shenyang geological survey Center of China geological survey Shenyang110000China Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Institutions of earth Science Chinese Academy of SciencesBeijing100029China College of earth and Planetary sciences University of Chinese Academy of SciencesBeijing100049China Development research Center of China geological survey Beijing100037China Shandong Academy of geological sciences Jinan250013China

The North China district has been subjected to significant research with regard to the ore-forming dynamics,processes,and quantitative forecasting of gold deposits;it accounts for the highest number of gold reserves and annual products in *** on the top-level design of geoscience theory and the method adopted by the National Key R&D Project(deep process and metallogenic mechanism of North China Craton(NCC)metallogenic system),this paper systematically collects and constructs the geoscience data(district,camp,and deposit scales)in four key gold districts of North China(Jiaojia-Sanshandao,Southern Zhaoping,Wulong,and Qingchengzi).The settings associated with the geological dynamics of gold deposits were quantitatively and synthetically analyzed,namely:NCC destruction,metallogenic events,genetic models,and exploration ***-dimensional(3D)and four-dimensional(4D)geological modeling was performed using the big data on the districts,while the district-scale 3D exploration criteria were integrated to construct a quantitative exploration *** them,FLAC3D modelling and the Geo Cube software(version 3.0)were used to implement the numerical simulation of the 3D geological models and the constraints of the fluid saturation parameters of the Jiaojia fault to reconstruct the 4D fault structure models of the Jiaojia fault(with a depth of 5000 m).Using Geo Cube3.0,multiple integration modules(general weights of evidence(Wof E),Boost Wof E,Fuzzy Wof E,Logistic Regression,Information Entropy,and Random Forest)and exploration criteria were integrated,while the C-V fractal classification of A,B and C targets in four districts was carried *** research results are summarized in the following four areas:(1)Four gold districts in the study area have more than three targets(the depth is 3000 m),and the class A,B and C targets exhibit a good spatial correlation with gold bodies that are controlled by mining engineering at depths greater than 1000 m.(2)The Boost Wof

关键词： Geoscience big data 3D/4D modeling Weights of evidence Random forest Target optimization and resources assessment Gold district in North China

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Evolution of the Piranshahr pull-apart basin at releasing stepovers of the strike-slip fault systems in Northwest of iran:Insights from twodimensional numerical modeling

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Journal of Mountain Science 2024年第12期21卷 4282-4298页

作者： SHOKRI Parisa ALAVI Seyed Ahmad GHASSEMI Mohammad Reza GANJIANI Seyed Mehdi Department of Sedimentary and Oil Basins Faculty of Earth SciencesShahid Beheshti UniversityTehran ***Iran research institute for earth sciences Geological Survey of IranTehran ***Iran Department of Mechanical Engineering University of TehranTehran ***Iran

The Piranshahr pull-apart basin,situated in the northwestern part of the Zagros Main Recent Fault(MRF),is characterized by two right-stepping segments of the dextral ***,a combination of finite element modeling techniques,especially twodimensional numerical modeling using ABAQUS software,along with field-based structural geological methods are used to assess the geometry and evolution of the pull-apart along the releasing stepovers in this strike-slip *** utilized numerical approach applies two-dimensional(2D)finite-element modeling related to elastic Newtonian rheology to evaluate the distribution of stress and localization of strain within the pull-apart *** study provides valuable insights into the factors controlling the shape,as well as exploring the interaction between the pre-existing structures in this right-lateral strike-slip releasing stepover,pull-apart basin development in strike-slip systems,and stress-strain behavior by studying the impact of boundary conditions and fault overlap on the deformation *** models consider three representative geometries of fault segment interactions,including underlapping,neutral,and overlapping stepovers,positioned at angles of 30°,45°,and 60°.The results indicate that increased overlap creates an extensive and elongated deformation pattern,while decrease overlap leads to block rotation and a narrow deformation *** addition,the degree of overlapping between parallel strike-slip faults influences the stress and *** mean normal stress within the transtensional basin,located between the fault segments,exhibits an extensional nature,while the region outside the stepover experiences general compressive mean normal *** Piranshahr transtensional pull-apart basin exemplifies the progressive evolution of underlapping stepovers,resulting in displaying an elongated rhomboidal to trapezoidal-shaped geometry over time.

关键词： Main Recent Fault Piranshahr pull-apart basin Releasing Stepover Finite element method ABAQUS software

A New Example of Retrograde Solubility Model for Carbonate Rocks

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1145-1146页

作者： LIU Lihong WANG Chunlian WANG Daming WANG Haida Oil & Gas survey China Geological Survey Oil and Gas research Center School of Earth and Space SciencesPeking University MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences China geological survey

Objective The dissolution and precipitation of carbonate during burial diagenetic process controls the reservoir property in deep buried strata. The geological process related with it has become a research focus during recent years. The most important dissolution fluids to carbonates are probably H2S and CO2 as byproducts of sulfate reduction in deep-buried setting with sulfate minerals, but carbonates are more soluble in relatively low temperature, which is the so-called retrograde solubility. Several geological processes can result in the decrease of temperature, including the upward migration of thermal fluids and tectonic uplift.

关键词： of on with well A New Example of Retrograde Solubility Model for Carbonate Rocks for

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

Two–stage Cretaceous Exhumation of Hengshan Complex in Hunan Province, SE China: Constraints Arising from ^(40)Ar–^(39)Ar Geochronology and Cretaceous Tectonic Implications

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Acta Geologica Sinica(English Edition) 2015年第6期89卷 1869-1881页

作者： WANG Yanhong CUI Jianjun ZHANG Yueqiao DONG Shuwen QI Wen SU Jinbao LI Jianhua LI Yong School of earth sciences and Resources China University of Geosciences institute of Geomechanics Chinese Academy of Geological Sciences Shaanxi geological and Mineral survey and Development Corporation School of earth sciences and Engineering Hehai University

The Hengshan complex is located in the central part of SE China, which underwent rapid tectonic uplift in the Cretaceous just like many other complexes on the continent. （40）~Ar-（39）~Ar geochronological data from the Hengshan complex suggest that two episodes of crustal cooling/extension took place in this part of the continent during the Cretaceous time. The first stage of exhumation was active during ca. 136-125 Ma, with a cooling rate of 〉 10 ℃Ma. The second stage of exhumation happened at ca. 98-93 Ma, with a cooling rate of 〉 10 ℃/Ma. Considering the folding in the Lower Cretaceous sedimentary rocks and the regional unconformity underneath the Upper Cretaceous red beds, it is believed that the Cretaceous crustal extension in SE China was interrupted by a compressional event. The reversion to extension, shortly after this middle Cretaceous compression, led to the rapid cooling/exhumation of the Hengshan complex at ca. 98-93 Ma. The Cretaceous tectonic processes in the hinterland of SE China could be controlled by interactions between the continental margin and the Paleo-pacific plate.

关键词： Hengshan complex Crustal extension Cretaceous tectonics 40Ar-39Ar geochronology SE China