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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 37-39页

作者： LI Chao LAI Wen HU Xiumian XU Yajun YANG Jianghai 无 Nanjing University Nanjing 210023JiangsuChina China University of Geosciences(Wuhan) Wuhan 430074HubeiChina the dde sedimentary data group

Within the framework of the Deep-time Digital Earth(dde)project,thematic databases driven by scientific issues will have strong scientific *** the field of sedimentology,thematic databases based on the current unified sedimentary knowledge tree established by the sedimentary data group(Fig.1),can solve specific scientific problems effectively and improve the scope and utility of the dde platform significantly.

关键词： dde platform thematic database sedimentary knowledge tree sedimentary data group

Low Resource Chinese Geological Text Named Entity Recognition Based on Prompt Learning

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Journal of Earth Science 2024年第3期35卷 1035-1043页

作者： Hang He Chao Ma Shan Ye Wenqiang Tang Yuxuan Zhou Zhen Yu Jiaxin Yi Li Hou Mingcai Hou State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Institute of Sedimentary GeologyCollege of Computer Science and Cyber SecurityChengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-Time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China School of Information Engineering China University of Geosciences(Beijing)Beijing 100083China

Geological reports are a significant accomplishment for geologists involved in geological investigations and scientific research as they contain rich data and textual *** the rapid development of science and technology,a large number of textual reports have accumulated in the field of ***,many non-hot topics and non-English speaking regions are neglected in mainstream geoscience databases for geological information mining,making it more challenging for some researchers to extract necessary information from these *** Language Processing(NLP)has obvious advantages in processing large amounts of textual *** objective of this paper is to identify geological named entities from Chinese geological texts using NLP *** propose the RoBERTa-Prompt-Tuning-NER method,which leverages the concept of Prompt Learning and requires only a small amount of annotated data to train superior models for recognizing geological named entities in low-resource dataset *** RoBERTa layer captures context-based information and longer-distance dependencies through dynamic word ***,we conducted experiments on the constructed Geological Named Entity Recognition(GNER)*** experimental results show that the proposed model achieves the highest F1 score of 80.64%among the four baseline algorithms,demonstrating the reliability and robustness of using the model for Named Entity Recognition of geological texts.

关键词： Prompt Learning Named Entity Recognition(NER) low resource geological text text information mining big data geology.

The Sedimentological Knowledge Tree:Significance,Method and Progress

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 34-36页

作者： LI Chao HU Xiumian HOU Mingcai WANG Chengshan YANG Jianghai 无 Nanjing University Jiangsu 210023China Chengdu University of Technology ChengduSichuan 610059China China University of Geosciences(Beijing) Beijing 100083China China University of Geosciences(Wuhan) WuhanHubei 430074China the dde sedimentary data group

On the platform of the Deep-time Digital Earth Program(dde),sedimentary data are essential for achieving its scientific *** data will take stratigraphic units as their core data carrier,for quantitative or qualitative data *** dde sedimentary data group is responsible for the management of the sedimentary data on the dde platform and has now developed into a group of nearly 40 disciplinary experts.

关键词： Sedimentology Deep-time Digital Earth data Science knowledge tree tree diagram

Application of plant DNA metabarcoding of lake sediments for monitoring vegetation compositions on the Tibetan Plateau

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Science China Earth Sciences 2024年第11期67卷 3594-3609页

作者： Kai WU Kai LI Weihan JIA Kathleen R.STOOF-LEICHSENRING Ulrike HERZSCHUH Jian NI Mengna LIAO Fang TIAN College of Life Sciences Zhejiang Normal University Polar Terrestrial Environmental Systems Research group Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Institute of Environmental Science and Geography University of Potsdam Institute of Biochemistry and Biology University of Potsdam College of Resource Environment and Tourism Capital Normal University

Benefiting from the rapid development of environmental DNA(eDNA) technologies, sedimentary DNA(sedDNA)emerges as a promising tool for monitoring plant compositions in remote regions. The Tibetan Plateau(TP), renowned for its harsh environment and numerous ponds and lakes, presents a potentially demanding region for the application of sedDNA on vegetation investigations. Here, we used the g and h universal primers for the P6 loop region of the chloroplast trn L(UAA)intron to amplify plant DNA in surface sediments from 59 ponds and small lakes on the southwestern TP. The applicability and limitations of using plant DNA metabarcoding for modern vegetation monitoring and palaeo-vegetation reconstructions have been assessed by comparing sedDNA, pollen, and vegetation survey data. Our results showed that plant DNA metabarcoding recorded 186 terrestrial taxa, of which 30.1% can be identified at the species level. The plant sedDNA approach can effectively disclose the dominant plant taxa(including Asteraceae, Cyperaceae and Poaceae) and significant vegetation assemblages in the vicinity of the investigated sites. The number of taxa and taxonomic resolution of plant sedDNA exceeded that of pollen analysis(75 taxa detected, 5.3% can be identified at species level). Unlike pollen that retains a broad spectrum of regional plant signals(including Pinus and Artemisia), plant sedDNA mirrors very local plants, underscoring its utility in local vegetation monitoring and reconstructions. To conclude, plant DNA metabarcoding of(small) lake sediments warrant increased attention in the future for local vegetation monitoring and reconstructions on the TP.

关键词： sedimentary DNA (sedDNA) Metabarcoding Pollen Vegetation composition Tibetan Plateau

Detrital-zircon geochronology of the Jurassic coal-bearing strata in the western Ordos Basin, North China: Evidences for multi-cycle sedimentation

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Geoscience Frontiers 2018年第6期9卷 1725-1743页

作者： Pei Guo Chiyang Liu Jianqiang Wang Yu Deng Guangzhou Mao Wenqing Wang State Key Laboratory of Continental Dynamics Department of Geology Northwest University Shandong Provincial Key Laboratory of Depositional Mineralization & sedimentary Minerals College of Earth Science and Engineering Shandong University of Science and Technology

The western Ordos Basin(WOB), situated in a tectonic transition zone in the North China Craton, acts as an excellent example for studying the Mesozoic intraplate sedimentation and deformation in Asia. In this study, U-Pb ages for 1203 detrital zircons of 14 sandstone samples collected from 11 sections are presented to unravel the sediment source locations and paleogeographic environments of the Early-Middle Jurassic coal-bearing Yan'an Formation in the WOB. data show that there are five prominent age groups in the detrital zircons of the Yan'an Formation, peaking at ca. 282 Ma, 426 Ma, 924 Ma, 1847 Ma, and2468 Ma. Samples from the northern, middle, and southern parts of the WOB contain these five age categories in various proportions. In the northern region, the Yan'an Formation exclusively contains Early Permian detrital zircons with a single age group peaking at 282 Ma, matching well with the crystallizing ages of the widespread Early Permian granites in the Yinshan Belt to the north and the Alxa Block to the northwest. While in the southern region, the Yan'an Formation mainly contains three groups of detrital zircons, with age peaks at 213 Ma, 426 Ma, and 924 Ma. These zircon ages resemble those of the igneous rocks in the Qilian-Qinling Orogenic Belt to the south-southwest. Samples in the middle region, characterized by a mixture age spectrum with peaks at 282 Ma, 426 Ma, 924 Ma, 1847 Ma and 2468 Ma, are previously thought to have mixed derivations from surrounding ranges. However, by referring to the detrital-zircon age compositions of the pre-Jurassic sedimentary successions and combining with paleontological and petrographic analysis, we firstly propose that the sediments of the Yan'an Formation in the middle region were partly recycled from the Triassic and Paleozoic sedimentary strata in the *** occurrence of recycled sedimentation suggests that the Late Triassic-Early Jurassic intraplate compressional deformation was very intense in the WOB, especially

关键词： Western Ordos Basin Yan’an Formation U-Pb geochronology Recycled zircon Intraplate deformation

sedimentary facies and depositional model of shallow water delta dominated by fluvial for Chang 8 oil-bearing group of Yanchang Formation in southwestern Ordos Basin,China

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Journal of Central South University 2015年第12期22卷 4749-4763页

作者：陈林陆永潮吴吉元邢凤存刘璐马义权饶丹彭丽 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education (China University of Geosciences (Wuhan)) Faculty of Earth Resources China University of Geosciences (Wuhan) Exploration and Development Institute Huabei Branch Company of SINOPEC Institute of sedimentary Geology Chengdu University of Technology

A systematic analysis of southwestern Ordos Basin's sedimentary characteristics,internal architectural element association styles and depositional model was illustrated through core statistics,well logging data and outcrop observations in Chang 8 oil-bearing *** analysis indicates that shallow water delta sediments dominated by a fluvial system is the primary sedimentary system of the Chang 8 oil-bearing group of the Yanchang Formation in southwestern Ordos *** microfacies with fine grain sizes are identified: distributary channels,sheet sandstone,mouth bar and interdistributary *** to the sandbody's spatial distribution and internal architecture,two types of sandbody architectural element associations are identified: amalgamated distributary channels and thin-layer lobate *** this sedimentary system,net-like distributary channels at the delta with a narrow ribbon shape compose the skeleton of the sandbody that extends further into the delta front and shades into contiguous lobate distribution sheet sandstone in the distal delta *** mouth bar is largely absent in this *** analyzing the palaeogeomorphology,the palaeostructure background,sedimentary characteristics,sedimentary facies types and spatial distribution of sedimentary facies during the Chang 8 period,a distinctive depositional model of the Chang 8 shallow water fluvial-dominated delta was established,which primarily consists of straight multi-phase amalgamated distributary channels in the delta plain,net-like distributary channels frequently diverting and converging in the proximal delta front,sheet sandstones with dispersing contiguous lobate shapes in the distal delta front,and prodelta or shallow lake mudstones.

关键词： sedimentary facies architectural element depositional model shallow water delta Chang 8 oil-bearing group Ordos Basin

bPermian, Lopingian, strontium isotopic ratio, conodont zone, marine carbonate, stable isotope chemostratigraphy

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Science China Earth Sciences 2015年第11期58卷 1951-1959页

作者： YE FaCheng LIU XinChun WANG Wei CHEN XiaoZheng LIU Jing SHEN ShuZhong WANG WenQian WANG XiangDong WANG Yue CAO ChangQun ZHENG QuanFeng ZHANG Hua ZHANG YiChun Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Institute of sedimentary Geology Chengdu University of Technology Chengdu 610059 China

The Lopingian is one of the fastest rising periods of seawater strontium isotopic ratios （^87Sr/^86Sr） in earth history, and its mechanisms and increasing rates of the ^87Sr/^86Sr evolution were still disputed widely. These disputations among researchers were caused mainly by timeframe selection （sections＇ thickness or data of radiometric ages）, and different stratigraphic boundaries and un-upmost dated ages. This paper examined published ^87Sr/^86Sr data of the Lopingian, and projected them on timescales based on evolutionary and age constrained conodonts fossils. ^87Sr/^86Sr evolution vs fossil constraining timescales was re-established in this period. This research suggests：（1） ^87Sr/^86Sr excursion projects on fossil zones can truly support ^87Sr/^86Sr evolutionary pattern in the period; （2） ^87Sr/^86Sr evolution provides a new approach for stratigraphic research of marine carbonate sections in lieu of biostratigraphic data; （3） ^87Sr/^86Sr stratigraphy works on marine carbonate sections of different sedimentation rates even between different basins; （4） the ^875r/^86Sr data and its shift was dependent on samples materials and chemical treatment methods; （5） the increasing rate of marine water ^875r/^86Sr in the Late Permian is suggested as 5.4× 10^-5/Ma or slightly lower; （6） sedimentation age and its ^875r/^86Sr of the Lopingian marine carbonate suggested as： Dpro=259-（Rs- 0.70695）/5.4×10^-5 （Ma）.

关键词： Permian Lopingian strontium isotopic ratio conodont zone marine carbonate stable isotope chemostratigraphy

Geochronology and geochemistry of Permo-Triassic sandstones in eastern Jilin Province(NE China): Implications for final closure of the Paleo-Asian Ocean

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Geoscience Frontiers 2019年第2期10卷 683-704页

作者： Qingxiang Du Zuozhen Han Xiaoli Shen Chao Han Zhigang Song Lihua Gao Mei Han Wenjian Zhong College of Earth Science and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Key Laboratory of Depositional Mineralization & sedimentary Mineral of Shandong Province Shandong University of Science and Technology

In the eastern part of the Central Asian Orogenic Belt(CAOB) in northeastern(NE) China, scattered outcrops of molasse deposits mark the ending of an orogeny and are crucial for understanding the evolution of the Paleo-Asian Ocean(PAO). However, the timing of tectonic events and the relationships among these strata remain controversial. To better constrain these geologic events, a comprehensive study of the detrital zircon U-Pb geochronology and geochemistry of the sandstones of the Kaishantun(KST) Formation and Kedao(KD) group in eastern Jilin Province, NE China, was conducted. The KST Formation is traditionally considered a molasse deposit. The sandstones display low CIA, PIA and high ICV values and low Th/U and Rb/Sr ratios, which suggest that the rocks were derived from an immature intermediate-felsic igneous source and experienced a simple sedimentary recycling history with relatively weak chemical weathering. LA-ICP-MS U-Pb dating of detrital zircons from two samples of the KST Formation yields ages of 748-252 Ma, suggesting that the KST Formation was deposited between 254.5 Ma and 252 Ma in Late Permian. The zircons were mainly derived from the continental northern part of the North China Craton(NCC). In contrast, the U-Pb dating of detrital zircons from five samples of the KD group yields ages of 2611-230 Ma, suggesting that the KD samples were deposited in the Early to Middle Triassic(ca. 248-233 Ma). The detrital zircon ages for the KD samples can be divided into groups with peaks at 2.5 Ga, 1.8 Ga, 800-1000 Ma, 500 Ma and 440-360 Ma, which suggest that the samples were derived from bidirectional provenances in the Jiamusi-Khanka Block and the NCC. These new data,combined with previously published results, suggest that at least three orogenic events occurred in central-eastern Jilin Province during the Early Permian(270-262 Ma), Early Triassic(254-248 Ma) and Middle-Late Triassic(242-227 Ma). The final closure of the PAO occurred during 242-227 Ma in the Mi

关键词： Detrital zircon Molasse Orogenic events Changchun-Yanji suture zone Paleo-Asian Ocean

The Upper Cretaceous-Paleogene of Phosphate Clays of the Ouled Bou Sbaa Deposit: Mineralogy, Geochemistry, and Beneficiation (Meskala, Morocco)

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Open Journal of Geology 2022年第2期12卷 156-178页

作者： Hanane El Boukhari Salem El Ouariti Mustapha Mouflih Mohammed Amine Nguidi Lászlό Kocsis Abdelmajid Benbouziane Laboratory of Dynamic of sedimentary Basins and Geological Correlations Hassan II University of Casablanca Casablanca Morocco Faculty of Science University Brunei Darussalam Geology Group Gadong Brunei Darussalam Brunei

This work aims first to characterize the Maastrichtian and Paleogene clays of the Ouled Bou Sbaa phosphate deposit located in the northern part of the Meskala Basin;and as a second goal, the most efficient clay fractions are tested and identified for organic dyes removal. Several techniques and methods have been adopted for the characterization of clays: X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF), Scanning electron microscope (SEM), and thermogravimetric analysis (TGA). Tests for the removal of methylene blue from clays were carried out by adsorption. The XRD study shows that the clays of the Ouled Bou Sbaa deposit contain fibrous clay types of palygorskite and sepiolite, and phyllite clays such as montmorillonite and illite. Stratigraphically, the Maastrichtian sample yielded, mainly aluminous clays dominated by montmorillonites, while in the Paleogene clays, the palygorskite-types clays, also rich in magnesium, are more common. The results of FTIR, XRF and SEM analyses confirm the mineralogical data, respectively, by the presence of characteristic bands and the dominance of oxides of silica, aluminum, magnesium, and the large dominance of palygorskite which is presented in the form of bundles or platelets of long fibers and montmorillonite which is presented in the form of a stack of sheets. The adsorption of methylene blue (MB) on these clays showed very fast fixation kinetics and a very efficient purifying power for this organic pollutant. The equilibrium isotherms were determined using the Langmuir, Freundlich and Elovich models. The results show that the Freundlich isotherm had better agreement with the methylene blue on clay with a correlation coefficient of 0.959.

关键词： Phosphate Clays Palygorskite Beneficiation Meskala Basin

Quantitative Expression of Paleogeographic Information Based on Big data

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 83-85页

作者： ZHAO Yingquan ZHONG Hanting XU Shenglin HOU Mingcai HU Xiumian ZHANG Lei GAO Yuan ZHANG Laiming LIU Yu CAO Haiyang MU Caineng CAI Pengcheng Institute of sedimentary Geology State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology)Chengdu 610059China Shandong Provincial Key Laboratory of Depositional Mineralization&sedimentary Minerals Qingdao 266510China State Key Laboratory of Mineral Deposit Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences and ResourcesChina University of Geosciences BeijingBeijing 100083China

Paleogeographic analysis accounts for an essential part of geological research,making important contributions in the reconstruction of depositional environments and tectonic evolution histories(Ingalls et al.,2016;Merdith et al.,2017),the prediction of mineral resource distributions in continental sedimentary basins(Sun and Wang,2009),and the investigation of climate patterns and ecosystems(Cox,2016).

关键词： paleogeography big data sedimentology Deep-time Digital Earth(dde)