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Journal of Geoscience and Environment Protection 2023年第1期11卷 150-168页

作者： Marc Ephrem Allialy Brice Roland Kouassi N’guessan Nestor Houssou Fossou Jean Luc Kouadio Davy Bedel Siogbo Félix Oufouet Konan UFR-STRM Felix Houphouet-Boigny University Abidjan C&#244 te d’Ivoire UFR-Biological Sciences Géosciences Department Peleforo Gon Coulibaly University of Korhogo Korhogo C&#244 te d’Ivoire Ministry of Mines Petroleum and Energy Abidjan C&#244 te d’Ivoire

Mount Fouimba and Mount Goma (Seguela) greenstone belts petro-structural studies combine remote sensing, geophysics, petrography and structural analysis. In view of establishing mapping details of paleoproterozoic geological formations, geological setting rocks observed are essentially magmatic formations, such as two-mica granite, granodiorites, and porphyritic basalts;and a few metamorphics which are metatonalite, amphibolites and amphibo-lopyroxenites. Remote sensing, such as Landsat 8 OLI satellite imagery and geophysical data, has been combined to show regional NNE-SW shear zone. Tectonic structures and microstructures have enabled to identify two main deformation phases: D1 phase corresponding to compression, and D2 is a transpression phase. Mechanisms responsible for deformations are respectively flattening and transpression. Geological formations derived from mantle origin but contain crustal components, and their tectonic setting occurred during subduction.

关键词： Petro-Structural Mapping greenstone belt Birimian Séguéla Côte D’Ivoire

Application of the modern ophiolite concept with special reference to Precambrian ophiolites

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Science China Earth Sciences 2011年第3期54卷 315-341页

作者： Timothy M. KUSKY WANG Lu Yildirim DILEK Paul ROBINSON PENG SongBai HUANG XuYa State Key Lab for Geological Processes and Mineral Resources Three Gorges Research Center for Geohazards Ministry of Education China University of Geosciences Wuhan 430074 China Department of Geology Miami University Oxford OH 45056 USA Department of Earth Sciences Dalhousie University Halifax Nova Scotia Canada

Much has been learned in the past 40 years about the great diversity of the internal structure and geochemical compositions of Phanerozoic ophiolites, indicating that these on-land fragments of ancient oceanic lithosphere formed in distinctly different tectonic settings during their igneous evolution. Recent studies in Archean and Proterozoic greenstone belts have shown that the Precambrian rock record may also include exposures of a diverse suite of ophiolite complexes as part of craton development in the early history of the Earth. We review the salient features of the Precambrian ophiolite record to highlight what has been learned about Precambrian oceanic spreading systems since the original Penrose definition of ophiolites in 1972. Some of the diagnostic, characteristic, typical, and rare aspects of ophiolites of all ages are presented in a table in order to help determine if tectonically deformed and metamophosed sequences in Precambrian shield areas may be considered as ophiolites. The results of this comparative study are important in that they enable researchers to more realistically characterize allochthonous mafic/ultramafic rock sequences as ophiolitic or non-ophiolitic. This approach is more deterministic in contrast to some other arbitrary classification schemes requiring three or four of the Penrose-style ophiolitic units to be present in the Precambrian record for a specific rock sequence to be considered ophiolitic. Once these tectonic fragments are recognized as remnants of ancient oceanic lithosphere, great progress shall be made in understanding early Earth history. We discuss the significance and implications of the Precambrian ophiolite record to constrain the mode and nature of the plate tectonics that operated in deep time.

关键词： ophiolite Precambrian craton greenstone belt

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Tectonic Setting of the Kadiri Schist belt, Andhra Pradesh, India

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 1992-2006页

作者： Sukanta GOSWAMI Pradeep K.UPADHYAY Purnajit BHATTACHARJEE Malaiandi G.MURUGAN Atomic Minerals Directorate for Exploration and Research Department of Atomic Energy

Plate tectonic activity has played a critical role in the development of petrotectonic associations in the Kadiri schist belt. The calc alkaline association of basalt, andesite, dacite and rhyolite （BADR） is the signature volcanic rock suite of the convergent margin. The N-S belt has gone below the unconformity plane of Cuddapah sediments. In the northern part geochemical and structural attributes of the Kadiri greenstone belt is studied along with microscopic observations of selected samples. Harker diagram plots of major elements generally indicate a liquid line of descent from a common source, such that BADR rocks are derived from a common parent magma of basaltic to andesitic composition. These calc-alkaline volcanic rocks are formed at convergent margins where more silicic rocks represent more highly fractionated melt. All the litho-units of this greenstone belt indicate crush and strain effects. The stretched pebbles in the deformed volcanic matrix with tectonite development along with associated greenschist facies metamorphism, alteration and hydration is remarkable. Flow foliation plane with N-S strike and very low angle （5~ to 10~） easterly dip and N-S axial planar schistosity formed due to later phase isoclinal folding can be clearly identified in the field. Basic intrusives are quite common in the surrounding area. All the observations including the field setting and geochemistry clearly demonstrate ocean-continent subduction as the tectonic environment of the study area.

关键词： Kadiri schist belt Tectonics Unconformity contact Ocean-continent subduction Andhra Pradesh Cuddapah basin greenstone belt

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The Neoarchean Ophiolite in the North China Craton:Early Precambrian Plate Tectonics and Scientific Debate

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Journal of Earth Science 2012年第3期23卷 277-284页

作者： Timothy M Kusky 翟明国 Three Gorges Research Center for Geo-hazards Ministry of EducationChina University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences

Archean greenstone belts and their possible inclusion of fragments of ophiolites is an im-portant research subject, since it is correlated with the nature of early oceanic crust, and can yield in-formation on the nature of early planetary lithospheres, the origin of TTG （tonalite-trondhjemite-granodiorite） continental crust, the formation of early cratons and continents, and is related to when plate tectonics started in the Earth＇s evolutionary history. This article briefly reviews the North China craton＇s Archean ophiolite argument and proposes further studies aimed at understanding the genera- tion of greenstone belts and Archean ophiolites, and suggests some key scientific questions that remain to be answered.

关键词： Archean ophiolite greenstone belt North China craton.

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A Quartz-Carbonate Gold Deposit in North Margin of Sino-Korean Archean Craton

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Continental Dynamics 2000年第1期 71-75页

作者： QIU Xiaoping Institute of Geology, CAGS, 100037, Beijing, China LI Chundong, YANG Zhishan and WANG Jun Zhangjiakou Gold Mine,075148, Xuanhua, Hebei Province, China

Xiaoyingpan gold mine is a typical quartz-carbonate gold deposit in the north margin of Sino-Korean Archean craton. The quartz-carbonate gold ore bodies are hosted in high-rank metamorphic greenstone. Their ore mineral compositions are simple and stable, but various alterations, such as silication, ferroan dolomite-breunnerite alteration, sericitic alteration and pyrite alteration developed in the bodies, especially, the ferroan dolomite alteration which played an important role in greenstone gold metallogenesis. In the field investigation of the Xiaoyingpan gold deposit, the authors discovered that ferroan dolomite alteration caused a mass of gold to replace early gold-quartz vein and mylonite, and rich gold lode formed. The gold-bearing ferroan dolomite in the mine has average (13C of -4.13‰, and its Pb-Pb isochron age is 2711(238 Ma. According to the structural settings and minerogenetic characteristics of the deposits, as well as the carbon and lead isotopic data of the gold-bearing ferroan dolomite, it can be determined that the Xiaoyingpan gold deposit belongs to high-grade metamorphic greenstone belt gold deposits. This is an important progress in gold deposit research in China.

关键词： quartz-carbonate gold lodes greenstone belt ankerite alteration Pb-Pb isochron dating Xiaoyingpan gold deposit.

Chronology and geochemistry of Neoarchean BIF-type iron deposits in the Yinshan Block,North China Craton:Implications for oceanic ridge subduction

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Chronology and geochemistry of Neoarchean BIF-type iron depo...