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Journal of Rare Earths 2008年第5期26卷 760-764页

作者：王强杨瑞东鲍淼 key {1. of isotope geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences School of Resources and Environmental Engineering Guizhou University

Rare earth elements （REEs） are good geological indicators. In order to understand REEs stratigraphic significance, REEs in Late Permian coal measure from Bijie City, western Guizhou Province, China were studied. The results showed that the contents of both light rare earth element （LREE） and ∑ REE were sharply increased in the boundary between Longtan Formation and Changxing Formation, which resulted from the gyration and discontinuity eruption of Emeishan basalt （REEs source） and frequent transgression-regression during forming coal. The coal measure and strata could be subdivided and correlate, and the sea-level change could be under stood by studying REEs content variation in coal measure.

关键词： stratigraphy source transgression-regression Bijie City Late Permian rare earths

Paleogene integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1290-1325页

作者： Jia LIU Ai SONG Lin DING Tao SU Zhekun ZHOU CAS key {1. of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China State key {1. of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Institute of Paleontology Yunnan UniversityKunming 650500China State key {1. of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

The Paleogene is a crucial period when terrestrial and marine ecosystems recovered from major disruptions and gradually approached their modern *** the Qinghai-Tibetan Plateau and its surrounding regions,the Paleogene also represents a significant phase of tectonic evolution in the Qinghai-Tibetan Plateau-Himalaya orogeny,reorganization of Asian climates,and evolution of *** to limitations in research conditions and understanding,there are still many controversies regarding stratigraphic divisions in the Qinghai-Tibetan Plateau and its surrounding *** recent years,extensive studies on sedimentary petrology,magnetostratigraphy,and isotope dating have been conducted in the *** fossils have been discovered and reported,contributing to a more systematic understanding of *** studies have laid a solid foundation for the comprehensive investigation of the stratigraphy,biotas and paleogeographic evolution of the Qinghai-Tibetan Plateau and its surrounding regions during the *** this paper,we integrate recent research on fossils,isotopic dating,magnetostratigraphy,and {1. to refine the stratigraphic divisions and correlation framework of different tectonic units in the region,building upon previous *** the Second Tibetan Plateau Scientific Expedition and Research,the knowledge of Paleogene floras has gradually *** paper discusses the biostratigraphic significance of extinct and newly appeared taxa based on the latest dating results of these plant *** new understanding of fossil species such as the“Eucalyptus”and Arecaceae establishes connections between the Paleogene flora of the Qinghai-Tibetan region and the biotas of Gondwana,specifically Oceania and South *** evolutionary history of key taxa near the Yarlung Zangbo suture zone indicates that the collision between the Indian and Eurasian plates occurred approximately 65-54 *** reconstructions,based o

关键词： Qinghai-Tibetan Plateau Fossils Biostratigraphy Paleoenvironment Paleogeography Paleogene

Occurrences of Excess ^(40)Ar in Hydrothermal Tourmaline: Interpretations from ^(40)Ar-^(39)Ar Dating Results by Stepwise Heating

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Acta Geologica Sinica(English Edition) 2007年第3期81卷 510-516页

作者： QIU Huaning PU Zhiping DAI Tongmo key {1. of isotope geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences P.O. Box 1131 Guangzhou Guangdong 510640

The occurrences of excess ^40Ar within a hydrothermal tourmaline is discussed in term of the analysis data of syngenetic muscovite and tourmaline from the Lushui hydrothermal tin-tungsten deposit in western Yunnan, China, using the ^40Ar-^39Ar stepwise heating technique. About 80% excess ^40 Ar was released in the last step when the tourmaline was fused, corresponding to a release of only -3% ^39 Ar （K）, which indicates that most excess ^40 Ar was held in the mineral lattice rather than in the channels parallel to the Z-axis. This suggests that the excess ^40 Ar was incorporated during crystallization and not diffused into the tourmaline during the post-crystallization history.

关键词： excess ^40 Ar tourmaline, ^40 Ar-^39 Ar stepwise heating hydrothermal tin-tungsten deposit Yunnan

Insight of enriched basalts into the nature and evolution of mantle lithosphere beneath craton margins

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Science China Earth Sciences 2024年第10期67卷 3128-3142页

作者： Hong-Kun DAI Jianping ZHENG Qing XIONG Linlin HU Xiang ZHOU State key {1. of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China

Refractory lithospheric deep roots are the cornerstone for the prolonged stability of cratons and mantle xenoliths are normally the key targets for study on the evolution of such deep roots. In regions with few mantle xenoliths, the basalts enriched in radiogenic isotopic compositions due to marked lithospheric mantle contribution are crucial to unmask the lithospheric mantle evolution based on a comprehensive study involving petrology, {1. and thermodynamic modelling. Here, the Early Cretaceous basalts from the northwest North China Craton with few mantle xenoliths are taken as an example to show the significance of enriched basalts on the study of lithospheric mantle. These basalts are characterized by high silica and alkali contents(SiO_(2)=45.8–59.8 wt.%, K_(2)O+Na_(2)O=4.81.9.88 wt.%), arc-type trace-element patterns and enriched radiogenic isotope compositions(e.g., ε_(Nd)=-2.64–-1..88,^(87)Sr/^(86)Sr=0.7063–0.7093). The TiO_(2) and FeO(total) contents are higher than those of natural and experimental melts from refractory mantle peridotite but comparable to those of partial melts of fertile mantle *** high contents of fluid-loving elements(e.g., Rb and Ba) suggest source metasomatism by aqueous fluids. Combined with thermodynamic modelling and regional tectonic history, these enriched basalts likely record simultaneous decompression melting of asthenosphere and low-extent melting of thin and fertile lithospheric mantle fluxed by aqueous fluids from the subducted Paleo-Asian oceanic slab. The newly unmasked lithospheric mantle under the western NCC contrasts with the coeval thick and refractory one supporting the eastern NCC, and highlights that the craton destruction, especially the loss of its ancient refractory mantle root, should take place in a diachronous manner related to the craton-girded subduction episodes. Our study illustrates the potential of enriched basalts to recover the nature and evolution of mantle lithosphere beneath craton m

关键词： Enriched basalts Lithospheric mantle Northwest North China Craton Tectonic histories Early Cretaceous

Mass and isotopic concentrations of water-insoluble refractory carbon in total suspended particulates at *** Observatory(China)

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Particuology 2015年第3期13卷 24-31页

作者： Xiangdong Zheng Chengde Shen Guojiang Wan Jie Tang Kexin Liu key {1. of Atmospheric Chemistry Chinese Academy of Meteorological Sciences State key {1. of isotope geochronology and geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences State key {1. of Environment geochemistry Institute of GeochemistryChinese Academy of Sciences Center of Meteorological Sounding Chinese Meteorological Administration State key {1. of Nuclear Physics and Technology and Institute of Heavy Ion Physics Peking University

Mass concentration and isotopic values δ1.C and 1.C are presented for the water-insoluble refractory carbon （WIRC） component of total suspended particulates （TSP）, collected weekly during 2003, as well as from October 2005 to May 2006 at the WMO-GAW Mt. Waliguan （WLG） site. The overall average WlRC mass concentration was （1.83 ± 1.0）ng/m3 （n = 79）, while seasonal averages were 2081.± 1.07 （spring）, 454±205 （summer）, 650 ±41. （autumn）, and 1.1. ± 703 （winter） ng/m3. Seasonal variations in WIRC mass concentrations were consistent with black carbon measurements from an aethalometer, although WIRC concentrations were typically higher, especially in winter and spring. The δ1.C PDB value （-25.3 ± 0.8）%0 determined for WIRC suggests that its sources are C3 biomass or fossil fuel combustion. No seasonal change in δ1.C PDB was evident. The average percent Modern Carbon （pMC） for 1.C in WIRC for winter and spring was （67.2 ± 7.7）% （n = 29）. Lower pMC values were associated with air masses trans- ported from the area east of WLG, while higher pMC values were associated with air masses from the Tibetan Plateau, southwest of WLG. Elevated pMC values with abnormally high mass concentrations of TSP and WIRC were measured during a dust storm event.

关键词： Water-insoluble refractory carbon (WIRC)Mass concentration81.C1.CMt. Waliguan (WLG)

The organic geochemistry of crude oil in the Saltpond Basin(Ghana):Organic source input,depositional environment,and thermal maturity

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Acta Geochimica 2024年第3期43卷 424-440页

作者： Kojo Amoako Ningning Zhong Nancy Pearl Osei-Boakye Ebenezer Apesegah Research Group for Marine geochemistry(ICBM-MPI Bridging Group) Institute for Chemistry and Biology of the Marine Environment(ICBM)School of Mathematics and ScienceCarl von Ossietzky UniversitäOldenburgAmmerläder HeerstraВ114-11826129 OldenburgGermany State key {1. of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing 102249China Petroleum Corporation GNPCPMBPetroleum HouseTemaGhana

The Saltpond Basin,situated within the South Atlantic margin of Ghana,is a significant area for petro-leum exploration but has received relatively limited research *** studies have examined source rock com-position,but data on crude oil organic chemistry are lack-ing,hindering understanding of the basin’s petroleum system and *** address this gap,we analyzed biomarkers and stable carbon-isotope ratios in Saltpond Basin crude oil using gas chromatography–mass spectrometry and gas chromatography–isotope ratio mass spectrometry to eluci-date organic matter source,depositional environment,and thermal *** were compared with oils from the West African segment of the South Atlantic margin,namely the Tano Basin and the Niger Delta Basin,to iden-tify potential correlations and gain insights into regional *** and isotopic results unveiled a sig-nificant prevalence of organic matter derived from lower marine *** of organic matter deposition and preservation in Saltpond oil samples suggested a suboxic marine transitional environment,contradicting conventional understanding of terrestrial dominance in such ***,the potential for degradation processes to obscure differentiation between terrestrial and marine organic mat-ter origins underscores the complex nature of organic mat-ter dynamics in transitional marine *** of molecular thermal maturity indices suggested Saltpond oils were expelled from source rocks exhibiting thermal maturity at the early maturity *** analysis unveiled genetic disparities among crude oils sourced from the Saltpond Basin and those from the Tano and Niger Delta Basin,primarily due to variations in source input and depo-sitional environment *** oil exhibits lower terrestrial organic input than Tano Basin’s crude oils,which also have less terrestrial input than Niger Delta Basin crude ***,its paleodepositional envi

关键词： Biomarkers Carbon isotopes Crude oil Saltpond Basin Ghana

LA-ICPMS Zircon U-Pb Dating for Three Indosinian Granitic Plutons from Central Hunan and Western Guangdong Provinces and Its Petrogenetic Implications

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Acta Geologica Sinica(English Edition) 2006年第5期80卷 660-669页

作者： PENG Bingxia WANG Yuejun FAN Weiming PENG Touping LIANG Xinquan key {1. of isotope geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou Guangdong 510640 Graduate School of the Chinese Academy of Sciences Beijing 100039

The LA-ICPMS zircon U-Pb geochronology of three typically Indosinian granitic plutons yielded weighted mean ^206pb/^238U ages of 21..1.5.9 Ma and 21..3±4.7 Ma for the biotite monzonitic granites from the Xiema and Xiangzikou plutons in Hunan Province, and 205.3±1.6 Ma for biotite granite from the Napeng pluton, western Guandong Province, respectively, showing a similar late Indosinian age of crystallization. In combination with other geochronological data from Indosinian granites within the South China Block （SCB）, it is proposed that those late Indosinian granites with an age of -21. Ma and the early Indosinian granites （230-245 Ma） have the similar petrogenesis in identical tectonic setting. The Indosinian granites within the SCB might be the products of anatexis of the thickening crust in a compressive regime. These data provide a further understanding for the temporal and spatial distribution of the Indosinian granites and the dynamic evolution of the SCB.

关键词： LA-ICPMS zircon dating Indosinian granite pluton thickening crust South China

On the timing and duration of the destruction of the North China Craton

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Chinese Science Bulletin 2009年第19期54卷 3379-3396页

作者： XU YiGang LI HongYan PANG ChongJin HE Bin key {1. of isotope geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The timing and duration of the destruction of the North China Craton, which is pivotal to understanding the destruction mechanism and its geodynamic controlling factors, still remain controversial. On the basis of the principles of magma genesis and evolution, first we outline magmatic expressions that can be related to cratonic destruction, then use magmatic and basin evolution trends to constrain the timescale of the lithospheric thinning in North China. The main conclusions include: (1. the thinning of the lithosphere beneath the North China Craton might have started, at least locally, since late Carboniferous-late Triassic, attained its climax during the late Jurassic-early Cretaceous, and continued till the end of late Cretaceous-early Cenozoic. The destruction of the North China Craton was a relatively slow, rather than a dramatic process. (2) The weakened lithospheric zones along the margins and interiors of the craton played an important role in cratonic destruction, partly accounting for the heterogeneous pattern of cratonic destruction. (3) The tectonic factors that controlled the destruction of the North China Craton may be multiple. The late Carboniferous southward subduction of the Paleo-Asian plate and the late Triassic collision between North China and South China may have re-activated the craton by influencing the thermal and integral structure of the craton. The Pacific subduction underneath the eastern Asian continent played a determinant role in the cratonic destruction, governing the distribution patterns of post-Mesozoic basins and major tectonic configuration, temporal change of magmatism and formation of the North-South gravity lineament.

关键词：地球动力学稳定地块研究调查

A Preliminary Report on Yong'anpu Tectonic Window in Suizhong County, Western Liaoning Province

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Journal of China University of Geosciences 2006年第3期17卷 231-237页

作者：汪洋姬广义 key {1. of isotope geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China Geological Institute of Beijing Municipality

For understanding the Mesozoic tectonics of Yanshan （燕山） belt, the authors took geological mapping in the belt. A large-scale thrust structure was identified in Yonganpu （永安堡） area. in the western part of Suizhong （绥中） County, Liaoning （辽宁） Province during our recent mapping in the Yanshan belt. The hanging wall of the thrust was composed of Archean gneiss and the overlying Early Cretaceous Zhangjiakou （张家口） Formation; meanwhile, the strongly ductile deformed volcanic rocks of Zhangjiakou Formation comprised the footwall in Yong＇anpu tectonic window. This discovery indicates the existence of strongly contractional deformation in the Yanshan belt after the eruption of Early Cretaceous Zhangjiakou volcanic rocks. On the basis of mapping and research, it is concluded that the published official geological maps have failed to identify the major structural features of the Yanshan belt.

关键词： thrust structure refolding structural mapping Early Cretaceous Yonganpu.

Shock-produced akimotoite in the Suizhou L6 chondrite

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Science China Earth Sciences 2015年第6期58卷 876-880页

作者： CHEN Ming XIE XianDe State key {1. of isotope geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences key {1. of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Shock-produced akimotoite was identified in the Suizhou chondritic meteorite, which occurs in two kinds of occurrence. The first is the irregular layers of akimotoite up to 4 ?m in thickness occurring in fractures and cracks of low-Ca pyroxene enclosed in the shock veins. The second is the zonal polycrystalline aggregates of akimotoite in shocked pyroxene grains close to the shock vein, where akimotoite occurs in a zonal area in between pyroxene and Mg Si O3-glass as irregular small clumps up to 5 ?m in size. This investigation suggests a solid-state transformation mechanism of pyroxene to akimotoite, and that akimotoite should have nucleated and grew in the area with abundant defects caused by shock deformation because the defect significantly enhances the solid-state reactivity and the kinetics of nucleation of high-pressure phase. The spatial relationship among the composed grains of pyroxene, akimotoite and Mg Si O3-glass(possibly vitrified perovskite) demonstrates a temperature gradient from the vein wall to the unmelted chondritic meteorite.

关键词： pyroxene akimotoite perovskite shock vein Suizhou meteorite