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Geochemistry,Zircon U-Pb Age and Hf Isotopic Constraints on the Petrogenesis of the Silurian Rhyolites in the Loei Fold Belt and Their Tectonic Implications

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Journal of Earth Science 2016年第3期27卷 391-402页

作者： Tianyu Zhao Xin Qian qinglai feng State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences China University of GeosciencesWuhan 430074China

Zircon U-Pb dating, Lu-Hf isotopic and geochemical data for the Silurian rhyolites from the Loei fold belt are presented to constrain their petrogenesis and tectonic settings. The rhyolites give a weighted mean 206Pb/238 U age of 423.7±2.7 Ma, and are characterized by high SiO2, Al2O3, K2 O and low MnO, MgO and P2O5. All samples are enriched in LILEs（e.g., Ba, K, Pb） and LREEs and depleted in HFSEs（e.g., Nb, Ta, Ti） with obvious negative Eu-anomalies（δEu=0.56–0.63）. The calc-alkaline rhyolites are typical arc-related rocks. The Loei rhyolites have high A/CNK ratios（1.19–1.34） and positive εHf（t）（4.03–5.38）, which can be interpreted as partial melting of juvenile crustal materials followed by multistage melting and differentiation, similar to highly fractional I-type rocks. Combined with regional geological surveys, the Loei rhyolites should be formed in a volcanic arc environment and may be in contact with the Truong Son fold belt during the Early Paleozoic. Moreover, the Simao Block might be in contiguity with the Indochina Block during Silurian.

关键词： I-type rhyolite zircon U-Pb dating Hf isotopic composition geochemical characteristics Loei fold belt Indochina Block

New Siliceous Microfossils from the Terreneuvian Yanjiahe Formation,South China:The Possible Earliest Radiolarian Fossil Record

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Journal of Earth Science 2018年第4期29卷 912-919页

作者： Shan Chang qinglai feng Lei Zhang School of Earth Sciences China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Radiolarians form an important part of the planktonic realm in the ocean of Early Paleozoic, but their origin and evolutionary processes has long been enigmatic. The ancestral representatives of radiolarians have been considered to belong to the order Archaeospicularia, whose unquestionable fossil records were dated back to the Middle Cambrian. Here we report ？Blastulospongia and unnamed spherical radiolarians in the Terreneuvian from the Yanjiabe Formation in Hubei Province, South China. Blastulospongia is an enigmatic siliceous microfossil genus, with affinities proposed amongst the radiolarian, sphinetozoan-grade sponges and uncertain protists. As for the newly discovered unnamed radiolarians, morphologically they possess latticed shell, spherical shape and are all small in size. Our discoveries support the idea that spherical radiolarians is an ancient representative, whose origin and diversification was probably much earlier than generally accepted. The hypothesis that the oldest radiolarians belong to the order Archaeospicularia needs to be re-examined.

关键词： Cambrian radiolarian ?Blastulospongia silica-biomineralization

Tracing Escaping Structure in the Northern Indo-China Peninsula by Openness and Remote Sensing

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Journal of Earth Science 2017年第1期28卷 147-160页

作者： Jie Zhang qinglai feng Zhi Zhang State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Nanjing Center China Geological Survey School of Earth Sciences China University of GeosciencesWuhan

The Openness based on DEM emphasizes the terrain convexity and concavity. It facilitates the interpretation of detailed landforms on the Earth＇s surface. Compared with the layer stacking of ETM＋ with less three-dimensionality and visualizability and with indefinite details of linear images in the deep cutting or deep covered region, the Openness is used for accurate interpretation of tectonic geomorphic units and linear structures. In this paper, the ETM＋ images（741 RGB） and RRIM based on Openness combined with the field geological investigation are used to trace the escaping structure in SE Asia. The east boundary is Ailaoshan shear zone and the west boundary is Uttaradit-Dien Bien Phu fault, which together form the southwards extruding wedge block. The arc boundary surface of the southern Khorat Plateau is jutted to the north. The NW and NE sides of Khorat Plateau are traversed by Uttaradit-Dien Bien Phu fault and Thakhek-Da Nang fault, respectively, resulting in a blocked escaping structure. The SE margins of Truong Son structure belt and Song Ma structure belt are both arcs jutting to SE. These arc structures clamped by faults or related to the fault on one side indicating the material flow direction obviously, are the most specific manifestation of escaping structures. Moreover, these push units are extruded from south to north successively.

关键词： Openness Indo-China Peninsula escaping structure remote sensing.

Petrography, Geochemistry and U-Pb Detrital Zircon Dating of the Clastic Phu Khat Formation in the Nakhon Thai Region, Thailand: Implications for Provenance and Geotectonic Setting

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Journal of Earth Science 2016年第3期27卷 329-349页

作者： Pradit Nulay Chongpan Chonglakmani qinglai feng School of Geotechnology Institute of Engineering Suranaree University of Technology Department of Mineral Resources Ministry of Natural Resources and Environment State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Earth Sciences China University of Geosciences

The purpose of this paper is to determine the provenance and tectonic setting of the Phu Khat Formation and get a better understanding of the tectonic evolution of the Nakhon Thai region using the petrography and whole-rock geochemistry integrated with the U-Pb detrital zircon dating. The sandstone of the Late Cretaceous to Early Tertiary Phu Khat Formation is chiefly characterized by unsorted texture and highly unstable volcanic lithic fragments. The formation overlies unconformably on a high textural and mineral maturity of clastic sandstone of the Late Cretaceous Khao Ya Puk Formation. Geochemically, the tectonic setting discrimination（K2O/Na2O-SiO2, Al2O3/SiO2-Fe2O3＋Mg O, and Th-Sc-Zr/10） and the petrography indicate that the Phu Khat Formation was accumulated in a passive margin tectonic setting which is the same as the Khao Ya Puk Formation but with a different depositional environment. The plots of geochemical provenance discrimination（La/Th-Hf, Th/Sc-Zr/Sc, Eu anomaly Eu/Eu＊ 0.42 to 0.74） and the petrography reveal that the provenance of the Khao Ya Puk Formation is mainly recycled sedimentary rocks while the Phu Khat Formation consists primarily of recycled sedimentary rocks associated with minor felsic volcanic rocks from the old continental island arc of the uplifted either western or eastern continental terranes or both. However, the U-Pb detrital zircon dating indicates a unique provenance of the Phu Khat Formation from the terrane west of the Nakhon Thai region where the volcanic continental arc is active predominantly in the Middle to Late Triassic. The results indicate that while the Phu Khat Formation was accumulated in Nakhon Thai region, the western terrane was uplifted by reactivation of the preexisting structure probably since the Maastrichtian time to be the source area of sediments. Meanwhile, the eastern terrane（mainly Loei-Phetchabun fold belt） had not been uplifted probably until, the accumulation of the Phu Khat Formation terminated. Subse

关键词： Phu Khat Formation provenance U-Pb detrital zircon dating geochemistry petrography

The Upper Ordovician Microfossil Assemblages from the Pagoda Formation in Zigui, Hubei Province

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Journal of Earth Science 2018年第4期29卷 900-911页

作者： Ke Zhang Aihua Yuan qinglai feng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Earth Sciences China University of Geosciences

The Pagoda Formation is a lithologically and biologically distinctive unit among the Upper Ordovician. The strata are characterized by a nodular limestone, which yields fossil assemblages of high diversity. Conodonts of 14 genera 20 species （6 undetermined species） and ostracods of 14 genera 26 species （16 undetermined species） are identified. In addition, spherical radiolarians and minute-walled foraminifers were first reported from this formation in South China. The conodont assemblage is attributed to the Hamarous europaeus Zone, which indicates the Early Katian Age. The conodont HDS biofacies, along with thin-shelled ostracods, spherical radiolarians and foraminifers, suggest relatively deep and quiet water depositional environment. Accordingly, these fossil materials not only enrich the diversity of the Pagoda biota, but also provide evidence for discussions of deposi- tional environments and stratigraphic correlations for the Pagoda Formation.

关键词： South China Ordovician conodont ostracod radiolarians foraminifer.

Uneven Distribution of Pseudotormentus De Wever et Caridroit(Radiolaria,Protozoa):Provincialism of a Permian Planktonic Microorganism

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1598-1610页

作者： ITO Tsuyoshi feng qinglai MATSUOKA Atsushi State Key Laboratory of Geo-processes and Mineral Resources China University of Geosciences Graduate School of Science and Technology Niigata University Research Institute of Geology and Geoinformation Geological Survey of Japan Department of Geology Faculty of ScienceNiigata University

The Permian planktonic distribution is not well known,in contrast to other fossil distributions of nekton and *** are representative microfossils of plankton in the Permian *** study compares both correlated radiolarian occurrences（Pseudotormentus De Wever et Caridroit and Quadriremis Nazarov et Ormiston） in literature data from the Pacific Rim and quantitative data from the Liuhuang and Gujingling sections in South *** distributions are concentrated in the Panthalassa,whereas Quadriremis occurrences are distributed over both the Panthalassa and the *** uneven distribution of Pseudotormentus seems to have been controlled by a difference in the oceanic basins,indicating the presence of faunal differences in Permian planktonic microorganisms between the Panthalassa and the *** other words,this study infers the provincialism of Permian planktonic *** uneven distribution is explainable by a hypothesis that Pseudotormentus was strongly affected by a Panthalassan equatorial current.

关键词： palaeobiogeography Palaeotethys Panthalassa Permian radiolaria Pseudotormentus Quadriremis

Extinction pattern and process of siliceous sponge spicules in deep-water during the latest Permian in South China

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Science China Earth Sciences 2008年第11期51卷 1623-1632页

作者： GuiChun Liu qinglai feng SongZhu Gu Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 4300

Diverse and abundant siliceous sponge spicules were found in the latest Permian beds, Dongpan and Ma’anying sections, South China, including 52 types and 85 forms. Further investigation on these spicules allows us to... 详细信息

关键词： siliceous sponge spicules Permian-Triassic extinction pattern process South China

Geochemical and geochronological constrains on the Chiang Khong volcanic rocks （northwestern Thailand） and its tectonic implications

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Frontiers of Earth Science 2013年第4期7卷 508-521页

作者： Xin QIAN qinglai feng Chongpan CHONGLAKMANI Denchok MONJAI State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China School of Geotechnology Suranaree University of Technology Nakhon Ratchasima 30000 Thailand

Volcanic rocks in northwestern Thailand exposed dominantly in the Chiang Khong area, are commonly considered to be genetically linked to the tectonic evolution of the Paleo-Tethyan Ocean. The volcanic rocks consist mainly of andesitic to rhyolitic rocks and are traditionally mapped as Permian-Triassic sequences. Our zircon U-Pb geochronological results show that two andesitic samples （TL-1-B and TL-31-B）, are representative of the Doi Yao volcanic zone, and give a mean weighted age of 241.2-＋-4.6 Ma and 241.7-＋-2.9 Ma, respectively. The rhyolitic sample （TL-32-B1） from the Doi Khun Ta Khuan volcanic zone erupted at 238.3＋3.8 Ma. Such ages indicate that Chiang Khong volcanic rocks erputed during the early Middle Triassic period. Seven samples from the Doi Yao and Doi Khun Ta Khuan zones exhibit an affinity to arc volcanics. Three rhyolitic samples from the Chiang Khong area have a geochemical affinity to both arc and syn-eollisional volcanic rocks. The Chiang Khong arc volcanic rocks can be geochemically compared with those in the Lampang area in northern Thailand, also consistent with those in Jinghong area of southwestern Yunnan. This indicates that the Chiang Rai arc-volcanic zone might northwardly link to the Lancangjiang volcanic zone in southwestern China.

关键词： volcanic rocks geochemistry zircon U-Pb age early Middle Triassic Chiang Khong northwestern Thailand

A Diverse Microfossil Assemblage from the Ediacaran–Cambrian Deep-Water Chert of the Liuchapo Formation in Guizhou Province,South China

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Journal of Earth Science 2023年第2期34卷 398-408页

作者： Yan Zhang Shan Chang qinglai feng Shucan Zheng State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430078China School of Earth Sciences China University of GeosciencesWuhan 430074China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China School of Architectural Engineering Huanggang Normal UniversityHuanggang 438000China

The Ediacaran to Cambrian transition witnessed great biological and environmental turnovers from the Precambrian to *** changes are also reflected by the fossil records during that ***,the fossil distribution was highly *** diverse fossils were constantly found from the shallow shelf including restricted basins,reports from deep-water areas,which are characterized by chert-dominated formations straddling the Ediacaran-Cambrian boundary,were *** them was the Liuchapo Formation that has been considered *** this study,a fossiliferous assemblage was found from the Liuchapo Formation in east Guizhou Province,South *** assemblage comprises Palaeopascichnus jiumenensis,Horodyskia minor,multicellular algae that possibly related with red algae,cyanobacteria,sponge spicules,small shelly fossils,membrane structures of uncertain affinity,and fossils with structures resemble the Ediacaran *** and Horodyskia have been widely reported and abundant in the Liuchapo Formation and equivalents,while the others have seldomly,or never,been found from this formation or,more widely,the deep-water chert of transitional *** discovery not only contributes to the rare paleontological records preserved in deep-water sediments,but also expanded the geographic distribution of the fossils,providing new materials of biological diversity during this critical interval.

关键词： Liuchapo Formation Early Cambrian latest Ediacaran deep-water chert fossils paleobiology