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Current Progress on the Geological Record of Microbialites and Microbial Carbonates

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 260-275页

作者： chen jitao LEE Jeong-Hyun Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences School of Earth and Environmental Sciences Seoul National University

This paper reviews the current progress and problems in the study of microbialites and microbial carbonates. Microbialites and microbial carbonates, formed during growth of microbes by their calcification and binding of detrital sediment, have recently become one of the most popular geological topics. They occur throughout the entire geological history, and bear important theoretical and economic significances due to their complex structures and formative processes. Microbialites are in place benthic microbial buildups, whereas microbial carbonates can be classified into two categories： stabilized microbial carbonates（i.e., carbonate microbialites, such as stromatolites and thrombolites） and mobilized microbial carbonates（i.e., microbial carbonate grains, such as oncoids and microbial lumps）. Various texture, structures, and morphologies of microbialites and microbial carbonates hamper the systematic description and classification. Moreover, complex calcification pathways and diagenetic modifications further obscure the origin of some microbialites and microbial carbonates. Recent findings of abundant sponge spicules in previously identified ＂microbialites＂ challenge the traditional views about the origins of these ＂microbialites＂ and their implications to reef evolution. Microbialites and microbial carbonates did not always flourish in the aftermath of extinction events, which, together with other evidences, suggests that they are affected not only by metazoans but also by other geological factors. Their growth, development, and demise are also closely related to sea-level changes, due to their dependence on water depth, clarity, nutrient, and sunlight. Detailed studies on microbialites and microbial carbonates throughout geological history would certainly help understand causes and effects of major geological events as well as the coevolution of life and environment.

关键词： microbialite microbial carbonate reef calcification calcimicrobe

Mercury oxidation and adsorption characteristics of potassium permanganate modified lignite semi-coke

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Journal of Environmental Sciences 2012年第12期24卷 2083-2090页

作者： Huawei Zhang jitao chen Peng Liang Li Wang College of Chemical and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke （SC） for gaseous Hg were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission. Brunauer-Emmett- Teller （BET） measurements, X-ray powder diffraction （XRD） and X-ray photoelectron spectroscopy （XPS） were used to analyze the surface physical and chemical properties of SC, Mn-SC and Mn-H-SC before and after mercury adsorption. The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke, such as the specific surface area, pore structure and surface chemical functional groups. The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature, but much higher at high temperature. Amorphous Mn7＋, Mn6＋ and Mn4＋ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg~, which oxidized the elemental mercury into Hg2＋ and captured it. Thermal treatment reduced the average oxidation degree of Mn2＋ on the surface of Mn-SC from 3.80 to 3.46. However, due to the formation of amorphous MnOx, the surface oxidation active sites for gaseous Hg0 increased, which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.

关键词： lignite semi-coke elemental mercury potassium permanganate modification removal efficiency

A curvelet-based method to determine wave directions from nautical X-band radar images

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Acta Oceanologica Sinica 2018年第1期37卷 11-19页

作者： ZHA Guozhen HE Qingyou GUAN Changlong chen jitao College of Oceanic and Atmospheric Sciences Ocean University of China Qingdao 266100 China Physical Oceanography Laboratory Ocean University of China Qingdao 266100 China State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Science Guangzhou 510301 China Hydrology Bureau of Yellow River Conservancy Commission Zhengzhou 450004 China

A new method to determine wave directions from nautical X-band images is proposed. The signatures of ocean waves show obvious scale and directional characteristics in nautical X-band radar images. Curvelet transform（CT） possesses very high scale and directional sensitivities. Therefore, it has good capability to analyze ocean wave fields. The radar images are decomposed at different scales, in different directions, and at different positions by CT, and curvelet coefficients are obtained. Given to the scale and directional characteristics of surface waves,the information of ocean waves is centralized in the curvelet coefficients of certain directions and at certain ***, the wave orientations can be determined. The 180 ambiguity is removed by calculating crosscorrelation coefficients（CCCs） between continuous collected images. The proposed method is verified by the dataset collected on the Northwest coast of the Zhangzi Island in the Yellow Sea of China from March to April 2009.

关键词： X-band radar wave direction surface wave curvelet transform

Microbially Induced Carbonate Precipitation in a Middle Triassic Microbial Mat Deposit from Southwestern China:New Implications for the Formational Process of Micrite

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Journal of Earth Science 2021年第3期32卷 633-645页

作者： Mao Luo jitao chen Wenkun Qie Jinyuan Huang Qiyue Zhang Changyong Zhou Wen Wen State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PalaeoenvironmentChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Institute of Geological Survey China University of GeosciencesWuhan 430074China chengdu Center of China Geological Survey Chengdu 610081China

Lime mud(i.e.,micrite)is a major component of carbonate *** mechanisms(biotic versus abiotic)have been proposed for the formation of lime mud in Earth’s ***,the detailed role that microbes play in the nucleation and subsequent precipitation of micrites remains to be *** we undertook a detailed geobiological characterization of laminated lime mudstone from the Middle Triassic Guanling Formation in Yunnan Province,southwestern *** features,together with previous geobiological investigations,suggest that the laminated lime mudstones represent the former presence of microbial *** lime mudstones consist mainly of calcite,dolomite and quartz,with clay minerals and pyrites as subordinate *** particular,micro-analysis shows copious nano-globules(65–878 nm)and capsule-shaped nano-rods in *** low-Mg calcite nano-globule aggregates are closely associated with mucilaginous biofilms resembling extracellular polymeric substances(EPS).Nano-sized globules coalesce to form semi-euhedral micrite *** suggest that a decaying hydrolytic destruction of the EPS by microbial communities within microbial mat leads to the precipitation of the nano-globules by enhancing alkalinity in local *** an intermediate,these nano-globules further aggregate to form micrite crystals possibly through a dissolution-reprecipitation process.

关键词： nano-globule EPS micrite microbial mat Middle Triassic Luoping Biota

Depositional Environments of the Upper Permian Quartzose Sandstone(Shandong Province, North China): Insight from Trace Element Geochemistry

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Journal of Earth Science 2015年第2期26卷 273-284页

作者： Dawei Lü Zengxue Li jitao chen Ying Liu Zengqi Zhang Jipo Liang Haiyan Liu Key Laboratory of Depositional Mineralization & Sedimentary Mineral (SDUST) Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Geological Institute of Shandong Province

The depositional environment of the Upper Permian quartzose sandstone （Kuishan sandstone in Shihezi Formation of Upper Permian） in the North China epicontinental basin is controversial. In order to test the previous hypotheses, we analyzed sedimentological characteristics of the Kuishan sandstones in outcrops and boreholes, and carried out trace element geochemical analysis by electron probe microanalyzer. Three lithofacies were recognized, including normal-graded conglomerate （Cng）, trough and planar cross-bedded coarse sandstone （CStpc）, and planar cross-bedded medium sandstone （MSpc）. Normal-graded conglomerate （Cng） formed in the meandering river or deltaic distributary channels. Trough and planar cross-bedded coarse sandstone （CStpc） formed in meandering river or distributary channels of near-source deltaic plain. Planar cross-bedded medium sandstone （MSpc） formed in the siliciclastic beach with highto moderate-energy conditions. By the petrology and trace elements analysis, three relatively large-scale transgressions were revealed. Each transgression was reflected by the lower content of Ba and ratios of Fe/Mn, and the high content of B and ratios of B/Ga. The ratios of Ni/Co of all samples are all lower than 2, suggesting oxygen-enriched shallower water en- vironment during deposition of the Kuishan sandstones.

关键词： Kuishan sandstone electron probe microanalysis (EPMA) depositional environment transgression regression.

Asymmetric double-layer composite electrolyte with enhanced ionic conductivity and interface stability for all-solid-state lithium metal batteries

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Chinese Chemical Letters 2021年第1期32卷 125-131页

作者： Binglu Zhao Luxiang Ma Kai Wu Mengxiong Cao Minggui Xu Xinxiang Zhang Wen Liu jitao chen Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100871China

All-solid-state Li metal battery has been regarded as a promising battery technology due to its high energy density based on the high capacity of lithium metal anode and high safety based on the all solid state electrolyte without inflammable ***,challenges still exist mainly in the poor contact and unstable interface between electrolyte and ***,we demonstrate an asymmetric design of the composite polymer electrolyte with two different layers to overcome the interface issues at both the cathode and the anode side *** the cathode side,the polypropylene carbonate layer has enough viscosity and flexibility to reduce the inter-facial resistance,while at the Li anode side,the polyethylene oxide layer modified with hexagonal boron nitride has high mechanical strength to suppress the Li dendrite *** to the synergetic effect between different components,the asprepared double layer composite polymer electrolyte demonstrates a large electrochemical window of5.17 V,a high ionic conductivity of 6.1×10~(-4) S/cm,and a transfe rence number of 0.56,featuring excellent ion transport kinetics and good chemical ***-solid-state Li metal battery assembled with LiFePO_4 cathode and Li anode delivers a high capacity of 150.9 mAh/g at 25℃ and 0.1 C-rate,showing great potential for practical applications.

关键词： All-solid-state battery Polymer electrolyte Lithium metal anode Interfacial engineering Lewis acid

Devonian 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 1036-1070页

作者： Wenkun QIE Kun LIANG Wen GUO Biao GAO Junjun SONG Bo chen Pu HUANG Li QIAO Honghe XU jitao chen Yucong SUN Yichun ZHANG State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Nanjing 211135China

The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in *** records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern ***,it is of great significance for explaining the global paleogeographic evolution,tectonic activities and biodiversity changes during this critical *** blocks on both sides of the southern Tienshan suture zone and the Longmu Co-ShuanghuChangning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions,showing important tectonic paleogeographic partitioning *** two suture zones represent the main branches of the PaleoAsian Ocean and the Paleo-Tethys Ocean,respectively,and on this basis the Devonian System can be subdivided into three types:the Tienshan type,the Tethys type and the Gondwana *** on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas,this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction,providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of *** results indicate that the North Qiangtang,South Qiangtang,Simao,Baoshan and Tengchong terranes,as well as the Himalaya Tethys Zone and the South China Block have affinities with the Indian Block,while the Lhasa Terrane has affinities with the Australian Block,and may be located between the South China and Australian *** the Emsian(Early Devonian),the South China Block separated from the northern margin of Gondwana,a process that was accompanied by the opening of the Jinshajiang-Ailaosh

关键词： Devonian Paleo-Tethys Ocean Integrative stratigraphy Biotas Provenance Analysis Paleogeography

Carboniferous integrative stratigraphy and timescale of China

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Science China Earth Sciences 2019年第1期62卷 135-153页

作者： Xiangdong WANG Keyi HU Wenkun QIE Qingyi SHENG Bo chen Wei LIN Le YAO Qiulai WANG Yuping QI jitao chen Zhuoting LIAO Junjun SONG CAS Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Center for Research and Education on Biological Evolution and Environment Nanjing University Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

The Carboniferous period lasted about 60 Myr, from ～358.9 Ma to ～298.9 Ma. According to the International Commission on Stratigraphy, the Carboniferous System is subdivided into two subsystems, i.e., Mississippian and Pennsylvanian, including 6 series and 7 stages. The Global Stratotype Sections and Points(GSSPs) of three stages have been ratified, the Tournaisian, Visean, and Bashkirian stages. The GSSPs of the remaining four stages(i.e., the Serpukhovian, Moscovian,Kasimovian, and Gzhelian) have not been ratified so far. This paper outlines Carboniferous stratigraphic subdivision and correlation on the basis of detailed biostratigraphy mainly from South China, and summarizes the Carboniferous chronostratigraphic framework of China. High-resolution biostratigraphic study reveals 37 conodont zones, 24 foraminiferal(including fusulinid) zones, 13 ammonoid zones, 10 brachiopod zones, and 10 rugose coral zones in the Carboniferous of China. The biostratigraphic framework based on these biozones warrants the precise correlation of regional stratigraphy of China(including2 subsystems, 4 series, and 8 stages) to that of the other regions globally. Meanwhile, the Carboniferous chemo-, sequence-,cyclo-, and event-stratigraphy of China have been intensively studied and can also be correlated worldwide. Future studies on the Carboniferous in China should focus on(1) the correlation between shallow-and deep-water facies and between marine and continental facies,(2) high-resolution astronomical cyclostratigraphy, and(3) paleoenvironment and paleoclimate analysis based on geochemical proxies such as strontium and oxygen isotopes, as well as stomatal indices of fossil plants.

关键词： Carboniferous Chronostratigraphy Biostratigraphy Chemostratigraphy Event stratigraphy Stratotype Stratigraphic correlation

Early diagenetic deformation structures of the Furongian ribbon rocks in Shandong Province of China——A new perspective of the genesis of limestone conglomerates

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Science China Earth Sciences 2010年第12期53卷 241-252页

作者： chen jitao HAN ZuoZhen ZHANG XiaoLei FAN AiPing YANG RenChao College of Geological Science and Engineering Shandong University of Science and TechnologyQingdao 266510China School of Earth and Environmental Sciences Seoul National UniversitySeoul 151-747South Korea

Ribbon rocks are characterized by an alternation of millimeter-to centimeter-thick limestone and argillaceous deposits (marlstone or shale).The sedimentary processes and diagenetic characteristics of ribbon rocks might be critical to the formation of limestone *** to detailed field measurement and laboratory analyses (thin section observation and XRD analysis),four types of ribbon rocks are classified,i.e.,limestone and marlstone couplet (L-M),limestone and shale couplet (L-S),thin-bedded lime mudstone (Ltb),and laminated limestone and marlstone couplet (Cl).These ribbon rocks were mostly deposited in low-energy subtidal environments (below fair-weather wave base).Ribbon rocks exhibit various subtle deformation structures such as intrastratal cracks and "boudin" *** cementation of carbonate and argillaceous layers during early diagenesis is a prerequisite condition for the deformation of ribbon rock under *** rocks would be deformed into limestone conglomerates under differential compaction that might be triggered by external forces such as storm and earthquake.

关键词： ribbon rock cracks 'boudin' structure early diagenesis pseudoconglomerate Furongian Shandong Province

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