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Mineral inclusions in zircon domains and geological significance of SHRIMP U-Pb dating for coesite-bearing zircons of paragneiss in Sulu terrane, eastern China

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Science China Earth Sciences 2005年第2期48卷 175-184页

作者： liu fulai YANG Jingsui XU Zhiqin Institute of Geology Chinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China

Laser Raman spectroscopy and cathodoluminescence (CL) image reveal that zircons separated from paragneisses in the southwestern Sulu terrane (eastern China) preserve multi-stage mineral assemblages in different zircon domains. In the same paragneiss zircon sample, some zircon grains retain inherited (detrital) cores with abundant low-pressure mineral inclusions of Qtz + Phe + Ap + impurities and Qtz + Phe + impurities. The ultrahigh-pressure (UHP) metamorphic overgrowths mantles of these zircons preserve Coe, Coe + Phe and other UHP mineral inclusions, indicating that these inherited (detrital) zircons from protoliths experienced metamorphic recrystallization during the Sulu UHP metamorphic event. However, other zircon grains preserve UHP mineral inclusions of Coe, Coe + Ap and Coe + Phe in the cores and mantles, whereas the outmost rims contain quartz (Qtz) and other low-pressure mineral inclusions. These phenomena prove that the second group zircons were crystallized at UHP metamorphic stage and overprinted by the late retrogressive metamorphism related to the Sulu terrane exhumation. SHRIMP U-Pb dating reveals that zircons separated from the paragneisses recorded complicated geochronological traces. Some zircons retain inherited cores with the 206Pb/238U ages of 284-754 Ma, indicating the complexity of the detrital zircons in protoliths. Coesite-bearing zircon domains recorded 238-266 Ma (with the average age of 245(14 Ma) for the UHP metamorphic event. The retrogressive rims of zircons recorded 213-223 Ma (with the average age of 217(15 Ma) for the late-stage amphibolite facies metamorphic event, indicating that the rapid exhumation time for the Sulu UHP terrane is about 220 Ma.

关键词： Sulu terrane, paragneiss, zircon, mineral inclusion, cathodoluminescence, SHRIMP U-Pb dating.

The progressive onset and evolution of Precambrian subduction and plate tectonics

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Science China Earth Sciences 2020年第12期63卷 2068-2086页

作者： Xiaolei Wang fulai liu Junyong Li Di Wang State Key laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Institute of Geology Chinese Academy of Geological SciencesBeijing100037China

The regime of plate tectonics on early Earth is one of the fundamental problems in Earth *** era takes the majority(ca.88%)of Earth’s history and thus plays a key role in understanding the onset of plate tectonics and the mechanism,distribution and process of Precambrian subduction *** paper presents a review on the progresses of subduction and subduction zones in different stages of Precambrian era,and sorts out some key issues and fields that merits further *** suggest that there was progressive onset and evolution of subduction and plate tectonics from Archean to Proterozoic *** emphasize the importance of comprehensive studies on subduction mechanism,metamorphic type,plate tectonics regime,the compositional evolution of continental crust,and petrogenesis of diverse granitoids formed in the *** is proposed that innovative analytical techniques,big data,experimental petrology and numerical geodynamic modeling will facilitate future studies of Precambrian subduction zones.

关键词： Precambrian Subduction Plate tectonics Continent formation Progressive evolu

Depositional Age, Provenance Characteristics and Tectonic Setting of the Ailaoshan Group in the Southwestern South China Block

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1687-1710页

作者： JI Lei liu fulai WANG Fang TIAN Zhonghua Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Beijing 100037China

The depositional and metamorphic ages and provenances of the Ailaoshan(ALS) Group in the Ailaoshan-Red River(ALS-RR) shear zone, southwestern South China Block(SCB), were investigated to constrain the tectonic history of the southwestern SCB. In this study, we use petrology, geochemical analysis, zircon cathodoluminescence imaging and UPb geochronology to analyse samples of quartzite, garnet-bearing two-mica schist and metapelite. The age spectra of detrital zircon grains from these metasediments show two dominant age peaks at 550–424 Ma and 876–730 Ma and two subordinate peaks at 970–955 Ma and ~2450 Ma. The youngest peak, corresponding to the early Palaeozoic, accounts for more than 20% of the total dates and constrains the deposition of the ALS Group to the Palaeozoic rather than the Palaeoproterozoic as traditionally thought. Moreover, two peaks of metamorphic ages corresponding to the Permo-Triassic and Cenozoic were also identified, and these ages document the tectonothermal events associated with the Indosinian collision between the Indochina Block and the SCB and the Himalayan collision between the Indian and Asian plates. Geochemical data suggest that the provenances of the ALS Group were dominated by continental arc and recycled metasedimentary rocks. The comparison of probability density distribution plots of the detrital zircon U-Pb age data indicates that the Neoproterozoic detritus in the ALS Group was probably derived from the arc-related Neoproterozoic intrusive bodies in the northwestern and southwestern SCB. Furthermore, the early Palaeozoic detritus might have been sourced from eroded early Palaeozoic strata and magmatic plutons in Cathaysia and volcanic rocks in the western Indochina Block.

关键词： detrital zircon depositional age provenance Ailaoshan Group South China Block

Magmatic Event at the End of the Archean in Eastern Hebei Province and Its Geological Implication

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Acta Geologica Sinica(English Edition) 2006年第6期80卷 819-833页

作者： GENG Yuansheng liu fulai YANG Chonghui Institute of Geology Chinese Academy of Geological Sciences Beijing 100037

By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ago, the Qingyangshu gabbroic gneiss 2536 Ma, the Yinmahe granodioritic gneiss near Lücao, Lulong County, 2533 Ma, the gabbro-dioritic gneiss near Longwan, Qianxi County, 2518-2515 Ma, the Qiuhuayu trondjemitic gneiss at Zunhua 2515 Ma, the Xiaoguanzhuang tonalitic gneiss at Zunhua 2495 Ma, and the Cuizhangzi gneiss in Qianxi County 2492 Ma. These geochronilogical data demonstrate that, though diverse in composition, type and origin, the granitic gneisses in eastern Hebei Province were emplaced and crystallized in a rather short period of magmatic activity. The formation of such a great amount of gneisses in this small time gap suggests that it was a critical crust accretion stage at the end of Neoarchean. The fact that granitoids of various types occurred at the same time implies a large-scale underplating （mantle plume） activity, which was then responsible for the crust accretion.

关键词： orthogneiss magmatic event Neoarchean zircon age eastern Hebei Province

Microscopic Analysis of Cementitious Sand and Gravel Damming Materia

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Fluid Dynamics & Materials Processing 2024年第4期20卷 749-769页

作者： Ran Wang Aimin Gong Shanqing Shao Baoli Qu Jing Xu fulai Wang Feipeng liu College of Water Conservancy Yunnan Agricultural UniversityKunming650201China Tianqi Engineering Consulting Co. Ltd.Kunming650000China Institute of International Rivers and Ecological Security Yunnan UniversityKunming650500China

The mechanical properties of cementitious sand and gravel damming material have been experimentally determined by means of microscopic SEM(Scanning Electron Microscopy)image *** results show that the combination of fly ash and water can fill the voids in cemented sand and gravel test blocks because of the presence of hydrated calcium silicate and other substances;thereby,the compactness and mechanical properties of these materials can be greatly *** every 10 kg/m^(3) increase in the amount of cementitious material,the density increases by about 2%,and the water content decreases by 0.2%.The amount of cementitious material used in the sand and gravel in these tests was 80-110 kg/m^(3),the water-binder ratio was ***,the splitting tensile strength was 1/10 of the compressive strength,and the maximum strength was 7.42 MPa at 90 *** optimal mix ratio has been found to be 50 kg of cement,60 kg of fly ash and 120 kg of water(C50F60W120).The related dry density was 2.6 g/cm^(3),the water content was 6%,and the water-binder ratio was 1.09.

关键词： Cementitious sand gravel material scanning electron microscopy optimal mix ratio maximum strength

Formation of Foliations and their Related Minerals from Diagenetic to Medium-grade Metamorphic Rocks:A Case Study of the Hongyanjing and Liao-Ji Backarc Basins,China

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1158-1170页

作者： TIAN Zhonghua WEN Fei liu fulai ZHU Haozhong YE Zhanghuang Key Laboratory of Deep-Earth Dynamics of the Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Shandong Provincial Key Laboratory of Depositional Mineralization&Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Jiangxi Science&Technology Normal University Nanchang 330038China

Deciphering the relationship between polyphase tectonic foliations and their associated mineral assemblages is significant in understanding the process from diagenesis to low-/medium-/high-grade *** can provide information related to strain,metamorphic conditions and overprinting relationships and so help reveal the tectonic evolution of *** this study,we predominately focus on the formation of foliations and their related minerals,as developed in two separate *** of all,two stages of axial plane cleavages(S1 and S2)were recognized in the Hongyanjing inter-arc basin,the formation of the S1 axial plane cleavage is associated with mica rotation and elongation in mudstones in the local *** pencil structure of S2 formed during the refolding phase,the minerals in the sedimentary rocks not changing their shape and ***,in the Liao-Ji backarc basin,foliations include diagenetic foliation(bedding parallel foliation),tectonic S1 foliation(secondary foliation or axial plane cleavage of S0 folding)and crenulation cleavage(S2).The formation mechanism of foliation changes from mineral rotation or elongation and mineral solution transfer in S1 to crystal-plastic deformation,dynamic recrystallization and micro-folding in *** index metamorphic minerals formed from low-grade to medium-grade consist of biotites,garnets,staurolite and kyanite,constituting a typical Barrovian metamorphic ***,a new classification of foliation is presented in this *** foliations can be divided into continuous and disjunctive foliations,based on the existence of microlithons,detectable with the aid of a *** foliation can be further sub-divided into spaced foliation and crenulation cleavage,according to whether(or not)crenulation(micro-folding)is *** size of the mineral grains is also significant for classification of the foliations.

关键词： new classification of foliations mineral transformation orogenesis Hongyanjing basin Liao-Ji backarc basin

Ultrahigh-pressure and Retrograde Metamorphic Ages for Paleozoic Protolith of Paragneiss in the Main Drill Hole of the Chinese Continental Scientific Drilling Project(CCSD-MH),SW Sulu UHP Terrane

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Acta Geologica Sinica(English Edition) 2006年第3期80卷 336-348页

作者： liu fulai XU Zhiqin XUE Huaimin ZHOU Kaifu Institute of Geology Chinese Academy of Geological Sciences Beijing 100037

Laser Raman spectroscopy and cathodoluminescence （CL） images show that most zircon crystals separated from paragneiss in the main drill hole of the Chinese Continental Scientific Drilling Project （CCSD-MH） at Maobei, southwestern Sulu terrane, contain low-pressure mineral-bearing detrital cores, coesite-bearing mantles and quartz-bearing or mineral inclusion-free rims. SHRIMP U-Pb dating on these zoned zircons yield three discrete and meaningful age groups. The detrital cores yield a large age span from 659 to 313 Ma, indicating the protolith age for the analyzed paragnelss is Paleozoic rather than Proterozoic. The coesite-bearing mantles yield a weighted mean age of 228 ± 5 Ma for the UHP event. The quartz-bearing outmost rims yield a weighted mean age of 213 ± 6 Ma for the retrogressive event related to the regional amphibolite facies metamorphism in the Sulu UHP terrane. Combined with previous SHRIMP U-Pb dating results from orthogneiss in CCSD-MH, it is suggested that both Neoproterozoic granitic protolith and Paleozoic sedimentary rocks were subducted to mantle depths in the Late Triassic. About 15 million years later, the Sulu UHP metamorphic rocks were exhumed to mid-crustal levels and overprinted by an amphibolite-facies retrogressive metamorphism. The exhumation rate deduced from the SHRIMP data and metamorphic P-T conditions is about 6.7 km/Ma. Such a fast exhumation suggests that the Sulu UHP paragnelss and orthogneiss returned towards the surface as a dominant part of a buoyant sliver, caused as a consequence of slab breakoff.

关键词： SHRIMP U-Pb dating zircon mineral inclusions Paleozoic protolith paragneiss Chinese Continental Scientific Drilling Project

Evolution of Diagenetic Fluid of the Dawsonite-Bearing Sandstone in the Jiyang Depression,Eastern China

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Journal of Ocean University of China 2024年第1期23卷 80-98页

作者： LI fulai MA Wenkuan ZHANG Chun WANG Kaining National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Shandong Geological Exploration Institute of China Chemical Geology and Mine Bureau Jinan 250013China

Based on the petrology,isotope geochemistry and fluid inclusions analysis,we established the evolutionary mode of the diagenetic fluid of dawsonite-bearing sandstone in the Jiyang ***-bearing sandstone is characterized by double injection of CO_(2)and oil-gas in the Jiyang Depression that have experienced a relatively complex diagenetic fluid evolution *** diagenetic sequence of secondary minerals involves secondary enlargement of quartz,kaolinite,first-stage calcite,dawsonite,second-stage calcite,ferrocalcite,dolomite and *** charging in the dawsonite-bearing sandstone occurred at around 2.6–0 *** CO_(2)charging event occurred during Dongying tectonism,forming the Pingfangwang CO_(2)gas reservoir,which provided an abundant carbon source for dawsonite *** and oxygen isotopic compositions of dawsonite demonstrate that CO_(2)forming the dawsonite was of an inorganic origin derived from the mantle,and that water mediating the proc-ess during dawsonite precipitation was sequestered brine with a fluid temperature of 82℃.The evolutionary sequence of the diagenetic fluid in the dawsonite-bearing sandstone was:alkaline syngenetic fluids,weak alkaline fluids during organic acid forma-tion,acidic fluids in the early stage of CO_(2)injection,alkaline fluids in the late stage of CO_(2)injection,and weak alkaline fluids during oil and gas *** mode indicates an increase in-HCO_(3)because of the CO_(2)injection,and the loss of Ca^(2+)and Mg^(2+)due to the precipitation of carbonate ***,the evolutionary mode of diagenetic fluids is in good agreement with high HCO_(3)^(-),low Ca^(2+)and low Mg^(2+)composition of the present formation water in the dawsonite-bearing sandstone.

关键词： evolution of diagenetic fluid dawsonite CO_(2)injection and hydrocarbon charging mineral diagenetic sequence iso-topic geochemistry fluid inclusions

Barite in omphacite-hosted K-feldspar + quartz poly-crystalline aggregates from the Sulu eclogites and its implications

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Chinese Science Bulletin 2007年第21期52卷 2995-3001页

作者： ZENG LingSen liu fulai LIANG FengHua CHEN FangYuan Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

K-feldspar + quartz polycrystalline aggregates were found as sub-millimeter-size inclusions with a pseudomorph after coesite (?) in omphacites from a number of Sulu eclogites. In these aggregates, round or subhedral barites occur as tiny inclusions in either K-feldspar or quartz. Energy dispersive spectroscopy (EDS) analyses show that these barites have (1) 33.86%―41.12% SO3, 0%―34.65% SrO, and 24.12%―63.55% BaO, (2) seemingly negative linear correlations between SrO and BaO, indicating that they are ideal solid solutions of barite (BaSO4) and celestite (SrSO4), and (3) highly variable Sr/Ba molar ratios ranging from 0 to 2.1. Presence of barites in the Sulu eclogites not only indicates oxidation of the subducting continental crust, but also very limited and restricted fluids pre- sented during exhumation of the Sulu UHP eclogites.

关键词：重晶石集料变质作用石英石