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Journal of Earth Science 2025年

作者： Yongheng Zhou Yaming Tang Bo Hong Fan Feng Longhui Wang Institute of geological survey， China University of Geosciences (Wuhan) Institute of Earth Environment， Chinese Academy of Sciences Xi'an geological survey Center China geological survey Chinese Academy of geological Sciences

Malan loess is highly water-sensitive， with its shear strength， particularly cohesive strength， significantly decreasing under the influence of water. The Western Shanxi Loess Plateau （WSLP） is especially prone to loess landslides， which are closely linked to rainfall infiltration. Understanding the regional variation of Malan loess cohesion (cm) and its distribution in relation to the developmental intensity of landslides in this area can provide essential scientific evidence for effective landslide prevention. Loess landslides and Malan loess were selected as the objects of study for the current research. The regional variation and distribution pattern of the cmwere revealed through undisturbed loess direct shear tests and Inverse Distance Weighting （IDW） interpolation. The relationship between the developmental intensity of landslide and the regional variation of the cmwas explored using the Cumulative Sum Variable Dimension Fractal （CSVDF）， Frequency Ratio （FR） model， and Certainty Factor （CF） model. The following conclusions were drawn: Results from the direct shear tests and IDW method indicate that the cmtends to decrease from south to north and exhibits a positively skewed spatial distribution pattern. The CSVDF results indicates a similarity between the regional variation of the cmand the development intensity of loess landslides. The FR and CF results reveal that loess landslides are more likely to occur when the cmis between 0 and 16.14 kPa.

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Tectonic setting of the Helong Block:Implications for the northern boundary of the eastern North China Craton

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Science China Earth Sciences 2005年第10期48卷 1599-1612页

作者： ZHANG Yanbin1, WU Fuyuan1, ZHAI Mingguo1 & LU Xiaoping1,2 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing 100029, China 2. regional geological and Mineral Resources survey of Jilin province, Changchun 130062, China Chinese Academy of Sciences regional geological and Mineral Resources survey of Jilin province

LA-ICP-MS zircon U-Pb dating indicates that the Bailiping granitic pluton was em-placed during Late Paleozoic to Early Cretaceous (285―116 Ma) by four distinct magmatic epi-sodes, arguing against the previous thought that the Bailiping granites were emplaced during Archean, Proterozoic or Early Paleozoic. It is suggested that the so-called Archean Jincheng-dong granite-greenstone belt, mainly composed of Bailiping granites, should be broken down. Sr-Nd isotopic compositions of the Bailiping granites are similar to those of the Phanerozoic granites in the Xing’an-Mongolian orogenic belt, suggesting that their parental magmas were mainly derived from a juvenile crust with some contamination of ancient crustal materials during magma rising and/or emplacement. Therefore, the basement of the Helong Block is similar to that in the northern Xing’an-Mongolian Orogenic Belt, but different from that of the North China Craton. It is proposed that the Archean Jinchengdong complex in this area is probably an exotic slice from the North China Craton, which indicates that the Fu’erhe-Gudonghe Fault, located in northern part of the Helong area, is not the boundary between the North China Craton and the Xing’an-Mongolian Orogenic Belt. The possible boundary should be located further southward more than 50 km and near the Baitoushan volcano.

关键词： LA-ICPMS ziron U-Pb dating, Bailiping complex, Helong Block, North China Craton, Sr-Nd isotope.

Trace element and REE geochemistry of Sanshenjiang gold deposit, southeastern Guizhou province, China

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Chinese Journal Of Geochemistry 2013年第2期32卷 212-221页

作者： LIU Kun YANG Ruidong CHEN Wenyong LIU Rui TAO Ping Guizhou University geological survey of Guizhou province

The Sanshenjiang gold deposit in southeastern Guizhou province, China, is hosted by the Neoproterozoic metasedimentary rocks which experienced low-grade greenschist facies metamorphism. Gold mineralization occurs mainly in the ribbon chiltern slate of the first member of the Longli Formation and is controlled by both strata and faults. Ore bodies are characterized by abundant quartz-arsenopyrite-gold-pyrite-bedding veins, veinlets and small lenses within the shear zone. In this study, trace element and REE geochemistry was analyzed to constrain the origin and genesis of this deposit. The trace element signatures of wall rocks and veins display a basically similar tendency in the spider diagram, showing the genetic relationship. The values of Co/Ni, Y/Ho, Hf/Sm, Nb/La and Th/La reflect that the hydrothermal fluids of this deposit were derived from the mixture of multiple sources with marked enrichment of Cl and moderate to high temperature. There is a broad similarity in the chondrite-normalized patterns and REE fractionation between wall rocks and ore bodies, possibly reflecting their similar origin. Based on the difference in δCe and δEu, quartz veins and lenses can be subdivided into weakly negative Ce-anomalies (δCe=0.81 to 1.06) with slight Eu anomalies (δEu=0.81 to 1.06) type and the significant positive Ce-anomalies (δCe=1.13 to 1.97) with moderate negative Eu-anomalies type, probably suggesting physical-chemical changes in the evolution process of ore-forming fluids from the early to late stage. It can be concluded that the ore-forming process may have experienced three stages: formation of the original ore source bed, regional metamorphism and gold mineralization, on the basis of trace element and REE analysis and field observation.

关键词：稀土元素地球化学特征微量元素金矿化东南部贵州省中国异常类型物理化学变化

Geochronology, Geochemistry and Sr-Nd-Hf Isotopes of Early–Middle Triassic Adakitic Plutons in Central-eastern Jilin province, NE China: Constraints on the Non-synchronous Closure of Paleo-Asian Ocean

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Acta Geologica Sinica(English Edition) 2022年第5期96卷 1615-1630页

作者： SHI Chenglong DING Xiaozhong ZHOU Xiaodong NIE Lijun ZHANG Jibiao Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China survey of regional geological and Mineral Resurce of Jilin province Changchun 130022China

The Changchun–Yanji suture zone(CYSZ) in NE China is considered as the suture between the North China Craton(NCC) and Central Asian Orogenic Belt(CAOB). The geochronology, geochemistry and Sr-NdHf isotopes of Early–Middle Triassic adakitic plutions from the CYSZ, are presented in this paper to discuss their petrogenesis and tectonic setting, as well as to constrain the timing and style of the Paleo-Asian Ocean's final closure. In Early Triassic, the Dayushan pluton(ca. 250 Ma) from western CYSZ has negative ε_(Nd)(t) values, bidirectional provenances(NCC and CAOB) of ε_(Hf)(t), which are formed in a collision tectonic setting. In contrast, in eastern CYSZ, the early Triassic samples in Liangshan(ca. 242 Ma) were high Mg~# values, positive ε_(Nd)(t), single provenances(CAOB) of ε_(Hf)(t) resulting from a subduction setting. In the Middle Triassic, the Atype granites in western CYSZ are found in previous studies representing a post-collisional extensional environment, whereas syn-collisional Lianyanfeng granites(ca. 237 Ma) in eastern CYSZ with low ISr and large scale ε_(Nd)(t) and ε_(Hf)(t) values from bidirectional provenances(NCC and CAOB), represent a collisional setting. The Paleo-Asian Ocean's occurred in a scissor-like fashion along the CYSZ during the Triassic period.

关键词： granitoids tectonic evolution Paleo-Asian Ocean Central Asian Orogenic belt

Zircon U–Pb Geochronology and Petrogenesis of Early–Midlle Permian Arc–Related Volcanic Rocks in Central Jilin: Implications for the Tectonic Evolution of the Eastern Segment of Central Asian Orogenic Belt

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Acta Geologica Sinica(English Edition) 2020年第4期94卷 1207-1222页

作者： SHI Chenglong DING Xiaozhong LIU Yanxue ZHOU Xiaodong NIE Lijun Institute of Geology Chinese Academy of Geological Sciences Beijing 100037China survey of regional geological and Mineral Resource of Jilin province Changchun 130022China

This paper presents age and geochemical data of a recently identified Late Paleozoic volcanic sequence in central Jilin province, with aims to discuss the petrogenesis and to constrain the tectonic evolution of the Central Asian Orogenic Belt in this area. Firstly, the volcanic rocks have zircon U-Pb ages of 290–270 Ma. Secondly, they are characterized by(a) ranging in composition from the low-K tholeiite series to high-K calc-alkaline series;(b) enrichment in light rare earth elements and depletion of heavy rare earth elements, with negative Eu anomalies;and(c) negative Nb, Ta, and Ti anomalies. Finally, the volcanic rocks yield εHf(t) values of +7.1 to +17. These data suggest that the central Jilin volcanic rocks were possibly derived from predominant partial melting of a depleted lithospheric mantle that might have been modified by subducted slab–derived fluids. Combined with previous studies, the Late Paleozoic–Early Mesozoic magmatism in Central Jilin can be divided into two stages:(a) a volcanic arc stage(290–270 Ma) represented by low-K to high–K, tholeiite to calc–alkaline plutons and(b) a syn–collisional stage(260–240 Ma) represented by high-K calc–alkaline I-type granites. Furthermore, the timing and the tectonic setting of the above magmatic rocks show that the arc was probably produced by the northward subduction of the Paleo-Asian Ocean and that the final closure of the Paleo-Asian Ocean occurred prior to the Early Triassic.

关键词： volcanic rocks zircon U-Pb age tectonic evolution Paleo–Asian Ocean

Timing and geochemical characters of the Sanchazi magmatic arc in Mianlüe tectonic zone,South Qinling

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Science China Earth Sciences 2004年第4期47卷 317-328页

作者： LI Shuguang1, HOU Zhenhui1, YANG Yongcheng2, SUN Weidong1,1), ZHANG Guowei3, & LI Qiuli1 1. School of Earth and Space Sciences,University of Science and Technology of China ,Hefei 230026,China 2. regional geological survey team of shaanxi province,Xianyang 712000, China 3. Department of Geology, Northwest University,Xi抋n 710069, China School of Earth and Space Sciences University of Science and Technology of China Hefei China regional geological survey team of shaanxi province Xianyang China Max-Planck-Institut f. Chemie Mainz Germany Department of Geology Northwest University Xi’an China

The Sanchazi mafic-ultramafic complex in Mianlüe tectonic zone,South Qinling can be subdivided into two blocks,*** paleo-magmatic arc and Zhuangkegou paleo-oceanic crust fragment (ophiolite).The Sanchazi paleo-magmatic arc is mainly composed of ande-site,basaltic and basalt-andesitic gabbro(or diorite),andesitic dyke,plagiogranite and minor ul-tramafric rocks,which have typical geochemical features of island arc volcanic rocks,such as high field strength element(***,Ti)depletions and lower Cr,Ni *** Light rare earth element (LREE) and K enrichments of these rocks and zircon xenocrystals of 900 Ma from plagiogranite suggest that this magmatic arc was developed on the South active continental margin of the South Qinling *** U-Pb age of (300±61) Ma for zircons from plagiogranite in-dicates that the Mianlüe paleo-oceanic crust was probably subducted underneath the South Qinling micro-continent in *** is consistent with the formation time (309Ma) of the Huwan eclogite originating form oceanic subduction in Dabie Mountains,suggesting that the Mianlüe paleo-ocean probably extended eastward to the Dabie Mountains in *** high-Mg adakitic rocks in Sanchazi paleo-magmatic arc suggest thet the subducted oceanic crust was relatively young (<25Ma) and hot.

关键词： Qinling orogen, magmatic arc, U-Pb zircon age, ophiolite complex.

Zircon Dating and geological Implications of Granitic Gneiss in the Metamorphic Zone of Gaoligong Mountains in Western Yunnan, China

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 440-453页

作者： TAN Xiaohong ZHAO Bo LI Xikang XU Zhangbao ZHANG Zhen Institute of geological survey of Yunnan province Institute of Mineral Resources Chinese Academy of Geological Sciences

The general classification of intermediate-acid intrusive rocks in the metamorphic zone of Gaoligong Mountains as one of the metamorphic terranes of Proterozoic Gaoligong Mountains is problematic regarding the intrusion stage and age, as well as the subsequent metamorphism and deformation. In this study, we investigated granitic gneiss in the metamorphic zone of Gaoligong Mountains based on the 1：50,000 regional geological survey of Qushi Street （2011-2013） and SHRIMP U-Pb zircon geochronology. Results showed that the SHRIMP U-Pb zircon dating of granitic gneiss ranged from 163.5±5.7 Ma to 74.0±2.0 Ma. Thus, the granitic gneiss was grouped into orthometamorphic rocks （metamorphic intrusions）. The dating data of granite rocks associated with intense metamorphism and deformation were divided into three groups, 163.5±5.7 to 162.3±3.1 Ma, 132.2-101.0 Ma and 99.4±3.5-74.0±2.0 Ma, which respectively represented three independent geologic events including an important magma intrusion with superimposed metamorphic effects in the late Middle Jurassic, regional dynamic metamorphism and superimposed reformation of fluid action in the early Cretaceous, and dynamic metamorphism dominated by ductile shear and metamorphism starting from the late Cretaceous.

关键词： Metamorphic zone granitic gneiss U-Pb zircon age Gaoligong Mountains Western Yunnan

Mineralogical studies of lazulite in Susong, Anhui province

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Chinese Science Bulletin 1996年第16期41卷 1369-1372页

作者：荆延仁汤加富高天山侯明金 Anhui Institute of regional geological survey Hefei 230011 China

Lazulite is a kind of rare mineral in nature. In China it was reported only in Guangdong and Inner Mongolia. It was not studied further because of its unreliable quantitative analysis or scarce data. Chemical analytical data of lazulite have been only obtained in Brazil and in the United States at present. By means of analyses, we have obtained reliable mineralogical and chemical data of lazulite in Susong for the first time in China.

关键词： lazulite topaz ultra-high pressure metamorphism Susong.

Newly developed evidence for the original Tethysan island-arc volcanic rocks in the southern segment of the South Lancangjiang Belt

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Chinese Journal Of Geochemistry 2007年第1期26卷 91-97页

作者：沈上越冯庆来魏启荣张志斌 Chinese University of Geosciences Institute of regional survey Yunnan Institute of Geological Survey

This paper re-describes the characteristics of pre-Ordovician (Pt3) metamorphic volcanic rocks in the Huimin-Manlai region of Yunnan province from the aspects of petrographic characteristics, rock assemblage, petrochemistry, REE, trace elements, lead isotopes and geotectonic setting. The metamorphic volcanic rocks maintain blasto-intergranular and blasto-andesitic textures; the volcanic rocks are characterized by a basalt-andesite-dacite assemblage; the volcanic rocks are basic-intermediate-intermediate-acid in chemical composition, belonging to semi-alkaline rocks, with calc-alkaline series and tholeiite series coexisting, and they are characterized by low TiO2 contents; their REE distribution patterns are of the LREE-enrichment right-inclined type; the volcanic rocks are enriched in large cation elements and commonly enriched in Th and partly depleted in Ti, Cr and P, belonging to the Gondwana type as viewed from their Pb isotopic composition; petrochemically the data points fall mostly within the field of island-arc volcanic rocks. All these characteristics provided new evidence for the existence of original Tethysan island-arc volcanic rocks in the region studied.

关键词：澜沧江南部地带原始特提斯岛弧火山岩新发育证据

THE LATE PRECAMBRIAN CRUSTAL EVOLUTION IN GUIZHOU province

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Chinese Science Bulletin 1982年第5期27卷 533-537页

作者：王砚耕谢俊帮陈玉林 regional geological survey team Geological Bureau of Guizhou Province

Strata of Upper Precambrian distribute widely and develop well in Guizhou province. They may be divided into two stratigraphic provinces-the Yangtze and Jiangnan (Fig. 1). The sequence is composed of Fanjingshan Group... 详细信息

关键词： stratigraphic Yangtze Strata Upper distribute sedimentary marginal sedimentation strata tectonic