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A ca. 2.2Ga Acidic Magmatic Event at the Northern Margin of the Yangtze Craton: Evidence from U-Pb Dating and Hf Isotope Analysis of Zircons from the Kongling Complex

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 872-873页

作者： XU Daliang WEI Yunxu PENG Lianhong DENG Xin HU Kun LIU Hao Wuhan Center of geological survey China Geological Survey Research Center of Granitic Diagenesis and Mineralization China Geological Survey Institute of geological survey China University of Geosciences (Wuhan)

Objective The Yangtze craton collisional orogeny at ca. extensional events at ca. 1 experienced Paleoproterozoic 1.95-2.0 Ga and post-orogenic 85 Ga related to amalgamation of the Columbia （Nuna） supercontinent （Zhao and Cawood, 2012）. A ca. 2.15 Ga suprasubduction zone ophiolitic melange was recongized in the Archean- Paleoproterozoic Kongling Complex of the northern Yangtze craton （Han et al., 2017）. However, the tectonic evolution in early Paleoproterozoic from 2.4 Ga to 2.2 Ga remains unclear. We report here the presence of a suite of Paleoproterozoic （2.2 Ga） granites in the Huangling dome, northern Yangtze craton, which may provide important insights into crustal growth processes in the craton prior to the assembly of Columbia.

关键词： Pb Hf Acidic Magmatic Event at the Northern Margin of the Yangtze Craton Evidence from U-Pb Dating and Hf Isotope Analysis of Zircons from the Kongling Complex Ga

In Situ Analyses of Trace Elements, U–Pb and Lu–Hf Isotopes in Zircons from the Tongshankou Granodiorite Porphyry in Southeast Hubei Province, Middle-Lower Yangtze River Metallogenic Belt, China

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Acta Geologica Sinica(English Edition) 2015年第5期89卷 1588-1600页

作者： XIA Jinlong HUANG Guicheng DING Lixue CHENG Shunbo Wuhan Center China Geological Survey Research Center of Granitaic Diagenesis and Mineralization China Geological Survey

The Tongshankou Cu-Mo deposit, located in southeast Hubei province, is a typical skarn–porphyry type ore deposit closely related to the Tongshankou granodiorite porphyry, characterized by a high Sr/Y *** in situ analyses of the trace elements and U–Pb and Lu–Hf isotopes in zircons from the Tongshankou granodiorite porphyry were *** any inherited zircons were observed, and the analyzed zircons yielded highly concordant results with a weighted mean 206Pb/238 U age of 143.5 ± 0.45 Ma（n=20, mean square weighted deviation was 0.75）, which was interpreted to represent the crystallization age of the Tongshankou granodiorite *** chondrite-normalized rare-earth element pattern was characterized by a slope that steeply rises from the light-group rare-earth elements（LREE） to the heavy-group rare-earth elements（HREE） with a positive Ce-anomaly and inconspicuous Eu-anomaly, which was coincident with the pattern of the zircons from the Chuquicamata West porphyry, *** analyzed zircons also had relatively low 176Hf/177 Hf ratios of 0.282526–*** t=143 Ma, the corresponding calculated initial Hf isotope compositions（εHf（t）） ranged from-5.6 *** results of the in situ analysis of trace elements and U–Pb and Lu–Hf isotopes in zircons from the Tongshankou granodiorite porphyry suggest that a deep-seated process involving a thickened-crust/enriched-mantle interaction may play an important role in the generation of high Sr/Y-ratio magma and potentially in the generation of porphyry Cu-Mo systems.

关键词： trace element zircon Hf isotope granodiorite porphyry Middle-Lower Yangtze River metallogenic belt

First Discovery of Gold Ore Bodies in the Lieryu Formation of the Liaohe Group in the Liaodong Area, China

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2342-2343页

作者： ZHANG Peng SHAO Jun LI Dongtao ZHAO Yan KOU Linlin BI Zhongwei Shenyang Institute of Geology and Mineral Resources Shenyang Center of geological SurveyChina Geological Survey

Objective Numerous large deposits magnesite, and talc are Liaodong area, within of lead-zinc, gold, boron, distributed throughout the different layers of the Paleoproterozoic Liaohe Group. The Liaohe Group comprises five formations as follows （from bottom to top）. The Langzishan Formation consists of volcaniclastic rocks containing copper, cobalt, and iron deposits. The Lieryu Formation is a set of volcanic sedimentary facies accompanied by small amounts of continental-margin mixed volcanic sedimentary rocks containing boron and magnetite deposits. The Gaojiayu Formation consists of carbonaceous clay-bearing carbonate rocks and contains the most important graphite deposit. The Dashiqao Formation consists of carbonate rocks containing lead-zinc and magnesite deposits. The Gaixian Formation comprises clastic and volcaniclastic rocks, and contains the most important gold deposit. Historically, gold prospecting has focused on the Gaixian Formation; however, gold ore bodies have been discovered during iron ore mining in the Lieryu Formation （Dayinggou area）, indicating possible existence of larger gold deposits in the area.

关键词： First Discovery of Gold Formation of the Liaohe

Liquid Immiscibility of Boninite in Xiangcheng, Southwestern China, and Its implication to Genetic Relationship between Boninite and Komatiitic Basalt

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Acta Geologica Sinica(English Edition) 2001年第1期75卷 74-93页

作者： Tetusro Urabe Takagi Naito geological survey of Japan Ibaraki 305 JapanGeological Survey of Japan Ibaraki 305 JapanGeological Survey of Japan Ibaraki 305 Japan

Boninitic rocks and associated high-magnesian basalt and high-iron tholeiite in the Xiangcheng area constitute the basal horizon of the arc volcanic sequence in the Triassic Yidun Island-Arc, southwestern China. The boninite occurs as pillow, massive and ocellar lavas; the last one possesses well-developed globular structure and alternates with the former two. The boninite is characterized by the absence of phenocrysts of olivine and low-Ca pyroxenes and by low CaO/Al2O3 ratios (1000 ppm) and Ni (>250 ppm). The normalized abundance patterns (NAP) of trace elements to primitive mantle are similar to the NAP of low-Ca modern boninites and SHMB in the Archaean and Proterozoic.

关键词： boninite komatiitic basalt liquid immiscibility Xiangcheng area of Sichuan

Geochronology and Petrochemistry of Volcanic Rocks in the Xaignabouli Area, NW Laos

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Journal of Earth Science 2019年第1期30卷 37-51页

作者： Meifeng Shi Zhenbo Wu Shusheng Liu Zhimin Peng Linnan Guo Fei Nie Siwei Xu Chengdu Center China Geological Survey

An integrated study of zircon U-Pb geochronology and petrochemistry, together with zircon Lu-Hf isotopes, has been carried out on the basaltic-andesitic tuff and volcanic breccia from the Nam Hang Formation and andesitic tuff from the Muang-Nan Formation in the Xaignabouli area, which had been mapped as the Permian–Early Triassic on the 1 : 1 000 000 geological map or Late Carboniferous on the 1 : 200 000 geological maps. Zircon U-Pb dating of three samples yielded weighted mean ages of 235±2.6, 232±1.4 and 278±2.8 Ma, respectively, suggesting a Late Triassic origin for the Nam Hang Formation and an Early Permian origin for the Muang-Nan Formation. Geochemically, they are characterized by depletions in HFSEs(e.g., Nb, Ta, Ti) and high LILE/HFSE ratios, and they have positive zircon ε_(Hf)(t) values of 8.7–15.9, which exhibits the continental arc volcanic affinity and partial melting of subducting oceanic slab in the magma source. Combined with spatial occurrence of the volcanic rock and existing geochronological and geochemical data, we suggest that the Xaignabouli-Luang Prabang volcanic belt can be linked to the Loei-Phetchabun belt. The Permian–Triassic volcanic rocks in this belt might be a product of the Nan back-arc basin eastward subduction.

关键词： volcanic rock zircon U-Pb geochronology geochemistry zircon Lu-Hf isotope Xaignabouli Laos

New Discovery and Zircon Hf Isotopic Composition of the Early Yanshannian Monzogranite in the Yingyangguan Group of Eastern Guangxi, China

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1653-1655页

作者： LI Xiang TU Bing WANG Lingzhan TIAN Yang XIE Guogang ZHANG Jianyu Wuhan Center of geological survey China Geological Survey Research Center of Granitic Diagenesis and Mineralization China Geological Survey School of Earth Sciences China University of Geosciences

Objective The Yingyangguan Group is widely exposed in the southwestern segment of boundary belt between Yangtze and Cathaysian blocks and is mainly composed of a suit of lower-grade metamorphic marine volcanoclastic- sedimentary rocks （Zhou Hanwen et al., 2002）. Its forming age and petrogenesis are critical for better understanding the orogenic process and relationship of the Yangtze and Cathaysian blocks since the Neoproterozoic. However, few zircon U-Pb ages of samples from the Yingyangguan Group have been reported, which are much debated, such as the metamorphic spilite （819±11 Ma）, keratophyre （415.1±2.1 Ma） and ignimbrite （821.3±3.9 Ma）（Tian Yang et al., 2015 and references in）. In this study, we focus on the new discovered Early Yanshannian monzogranite and its mafic enclaves from the Yingyangguan Group, and conducted zircon U-Pb dating and in-situ Hf isotopic analyses to constrain their petrogenesis.

关键词： Hf ICP MS Pb New Discovery and Zircon Hf Isotopic Composition of the Early Yanshannian Monzogranite in the Yingyangguan Group of Eastern Guangxi China

Landslide Developmental Characteristics and Response to Climate Change since the Last Glacial in the Upper Reaches of the Yellow River, NE Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 635-646页

作者： YIN Zhiqiang QIN Xiaoguang YIN Yueping ZHAO Wuji WEI Gang Institute of Geology and Geophysics Chinese Academy of Sciences China Institute of Geo-environment Monitoring China University of Geosciences (Beijing) qinghai Environmental geological Prospecting bureau

The upper reaches of the Yellow River in northeastern Tibetan Plateau are geohazards *** evolution of the Yellow River,chronology of some landslides,and spatiotemporal distribution characteristics of super large scale and giant landslides within the region are summarized using paleoclimate evidence,and the relationship between the intensive landslide period and climatic changes since the Last Glacial period is *** is concluded that （1） Super large scale and giant landslides are distributed widely within the region,particularly in the Qunke-Jianzha basin.（2） The chronological sequence of landslides is established by dating the slip zones of landslides and analyzing the relations between landslides and their overlying or underlying loess *** landslide development periods are determined：53-49 ka BP,33-24 ka BP,10-8 ka BP,5-3.5 ka BP,and the present.（3） These correspond closely to warm and wet periods during the last 100,000 years,i.e.,two weak paleosol development stages of Malan loess deposited during the last Glacial period in the Chinese loess Plateau,L1-4 and L1-2 that belong to the marine oxygen isotope stage 3,the last deglaeial period,the Holocene Optimum,and the modern global warming period.（4） Landslide triggers may be closely linked to warm and wet periods related to rapid climatic transitions.

关键词： landslide developmental characteristics climate change upper reaches of the Yellow River response

New Discovery of Shizhushan Superlarge Wollastonite Deposit in Xinyu City, Jiangxi Province

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 1670-1671页

作者： HU Zhenghua WANG Xlanguang CHEN Guohua LI Yanhong ZHAN Tlanwe CHEN Sibao LIU Shaohua CHEN Xuguang geological survey of Jiangxi Province Nanchang 330000 China Administration of geological Prospecting Fund of Jiangxi Province Nanchang 330030 China China University of Geosciences Beijing 100083 China geological Party Coal Geological Bureau of Jiangxi Province Xinyu 336600 Jiangxi China

Objective The Mengshan area of the Xinyu City, Jiangxi Province is an important wollastonite production base in China. As early as the 90s of the 20th century, more than ten medium to small-sized wollastonite deposits, such as the Yueguangshan and Caofangmiao Deposits were discovered in the outer contact zone of the Mengshan rock mass. After that, no more progress was achieved in wollastonite prospection. In 2016, the project funded by the geological Prospecting Fund of Jiangxi Province made significant breakthroughs in the ＂General survey of the Shizhushan Wollastonite Ore in the Yushui District and Zhangmuqiao Wollastonite Ore in Shanggao County, Xinyu City, Jiangxi Province＂ in the Mengshan area. The new discovered Shizhushan Wollastonite Deposit has a scale of 50 million tons and its resources scale far exceeds that of the Seeleys Bay Wollastonite Deposit discovered in Canada.

关键词： New Discovery of Shizhushan Superlarge Wollastonite Deposit in Xinyu City Jiangxi Province

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Towards the Triassic Configuration of Western Paleotethys

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Journal of Earth Science 2022年第6期33卷 1494-1512页

作者： Darko Spahić Department of geological Mapping Geological Survey of Serbia11000BelgradeSerbia

The tectono-paleogeograhic inheritance of barely documented Paleotethyan influence on the Southern Carpathian-Balkan belt is herein reappraised to highlight complex processes occurring along an alternative branched configuration of Triassic fossil subduction zone *** absence of Paleotethyan oceanic accretionary complexes,and the unavailability of rocks returned from poorly traceable Triassic subduction zones allow no conventional insights into its internal *** contrast,the adjoining Dinarides and investigated western Southern Carpathian-Balkan belt contain metamorphic rocks ejected from the precursory Late Paleozoic Paleotethyan active *** inventory and reappraisal of Variscan and Cimmerian imprints,far-field effects place the peri-Moesian Southern Carpathian-Balkan belt into the overriding plate position above the Triassic Paleotethyan active *** Permian–Early Triassic dragging of underlying Paleotethyan crustal material beneath external segments of the continental margin is contemporaneous with the onset and formation of several episutural back-arc *** include the Maliac Ocean with a here introduced NNW-SSE striking Lower–Middle Triassic marginal shallow-water clastic-carbonate basin of Getic Unit(Gornjak nappe)that is spatially in line with the“Volvi-Therma”western Rhodope aborted Triassic rift *** carbonate platform deposition was interrupted by a change in the geodynamic regime at the end of the Middle Triassic(inducing mild compressional deformations and the regional uplift resulting in missing of Upper Triassic sediments).The constraints on the investigated sequences yield that the lagged Paleotethyan closure in the Balkan sector occurred during the late Ladinian-Carnian interval.

关键词： Paleotethys Eocimmerian docking Serbo-Macedonian Unit Mali Jastrebac granitoids Gornjak sequence Upper Triassic unconformity geodynamics

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