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Chemostratigraphic Characterization Tests on Sedimentary Formations in the Côte D’Ivoire Offshore Basin: Case of A-X and B-X Wells
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作者 Kokoa Chia Marie Reine Kra Akoua Clarisse +2 位作者 Irié Bi Trazié Gaël Coulibaly Sougo Aoua Affian Kouadio 《Open Journal of Applied Sciences》 2023年第10期1820-1833,共14页
The tests performed with two hundred and thirty-nine (239) samples from the A-X and B-X drillings help to know their sedimentological and chemostratigraphic characters. In sedimentological term formations are composed... The tests performed with two hundred and thirty-nine (239) samples from the A-X and B-X drillings help to know their sedimentological and chemostratigraphic characters. In sedimentological term formations are composed of sand, sandstone, limestone, siltstone and argillite that alternate along the drill. In chemostratigraphic term two megasequences (MS1 and MS2) have been identified. A correlation of chemostratigraphic data completed by the lithology results allowed a subdivision of oil wells that shows two main types of deposits environments. First, a proximal marine environment to continental and to Albian marked by a detrital flow deducted from the concentrations evolution of indicator elements of terrigenous material that are K, Mg, and Rb. On the other hand, a deep to shallow marine environment of Cenomanian to Paleocene marked by the presence of predominantly clay sediments and abundant glauconite in the lower Senonian. Nevertheless, there is a transition or intermediate environment that is characterized by the presence of glauconite and detrital flows. 展开更多
关键词 chemostratigraphy CHARACTERIZATION Sediments Offshore Basin Albian-Paleocene Ivory Coast
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Chemostratigraphy of Flood Basalts in the Garze-Litang Region and Zongza Block: Implications for Western Extension of the Emeishan Large Igneous Province, SW China 被引量:18
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作者 XIAOLong XUYigang +2 位作者 XUJifeng HEBin PirajnoFRANCO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期61-67,共7页
The Late Permian Emeishan Large Igneous Province (ELIP) is commonly regarded as being located in the western part of the Yangtze craton, SW China, with an asymmetrical shape and a small area. This area, however, is ju... The Late Permian Emeishan Large Igneous Province (ELIP) is commonly regarded as being located in the western part of the Yangtze craton, SW China, with an asymmetrical shape and a small area. This area, however, is just a maximum estimation because some parts of the ELIP were not recognized or dismembered and destroyed during the Triassic to Cenozoic tectonism. In this paper, the chemostratigraphical data of the Zongza block, the Garze-Litang belt and the Songpan-Garze block suggest that the Late Permian basalts in these areas have remarkable similarities to the ELIP basalts in petrography and geochemistry. Flood basalts in the Sanjiangkou area are composed of the lower part of the low-Ti (LT) tholeiite and the upper part of the high-Ti (HT) tholeiite, which is the same as the flood basalts on the western margin of the Yangtze craton. Flood basalts in the Zongza and Songpan-Garze areas, which are far from the Yangtze craton, consist of HT tholeiite only. This is the same as the flood basalts within the Yangtze craton. Therefore we argue that these contemporary basalts all originated from the Emeishan mantle plume, and the ELIP could have a significant westward extension with an outcropped area of over 500,000 km2. This new scenario shows that the LT tholeiite occurs on the western margin of the Yangtze craton, while the HT tholeiite overlying the LT basalts occupies the whole area of the ELIP. 展开更多
关键词 Emeishan large igneous province flood basalts chemostratigraphy Yangtze craton Garze-Litang Zongza block
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Biostratigraphic and Chemostratigraphic Correlation for the Base of the Middle Ordovician between Yichang and Western Zhejiang Areas,South China 被引量:4
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作者 ZHANG Yuandong Axel MUNNECKE +2 位作者 CHEN Xu CHENG Junfeng LIU Xiao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第2期320-329,共10页
The base of the Middle Ordovician (i.e. Dapingian Stage) has been defined at the first appearance datum (FAD) of conodont Baltoniodus? triangularis at Huanghuachang, Yichang, China,but the precise correlation of ... The base of the Middle Ordovician (i.e. Dapingian Stage) has been defined at the first appearance datum (FAD) of conodont Baltoniodus? triangularis at Huanghuachang, Yichang, China,but the precise correlation of the boundary to regions of other facies remain to be resolved. Herein we review the biostratigraphy and chemostratigraphy of the Huanghuachang Global Standard Stratotype-Section and Point (GSSP) section, and present our latest stratigraphic work on the nearby Chenjiahe s ection in Yichang, and the Hengtang Quarry section, Jiangshan, Zhejiang, which is regarded as representative of slope facies. The conodont and graptolite biostratigraphy as well as chemostratigraphy of the Chenjiahe section indicate that the base of the Middle Ordovician also falls within the graptolite Azygograptus suecicus Zone, and coincides with a high or maximum δ13C value within a minor positive carbon isotope excursion, suggesting that the base boundary can be readily recognized across the entire Yangtze Gorges area. The integrated graptolite and conodont biostratigraphy and chemostratigraphy of the Hengtang section, Jiangshan, indicates that the basal boundary probably falls within the graptolite lsograptus caduceus imitatus Zone that overlies the Azygograptus suecicus Zone, and coincides with a remarkable drop of δ13C. This difference indicates that a multi-disciplinary approach is critical to identify the base boundary in those regions where the Baltoniodus ? triangularis is absent. 展开更多
关键词 Graptolite biostratigraphy chemostratigraphy Middle Ordovician slope facies South China
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Advances in sediment geochemistry and chemostratigraphy for reservoir characterization 被引量:2
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作者 Mu Ramkumar R.Nagarajan M.Santosh 《Energy Geoscience》 2021年第4期308-326,共19页
Sedimentary sequences preserve the records of changes in major controls of sedimentation namely,tectonics,climate,relative sea level and sediment production and preservation.The potential to characterize these changes... Sedimentary sequences preserve the records of changes in major controls of sedimentation namely,tectonics,climate,relative sea level and sediment production and preservation.The potential to characterize these changes in spatial and temporal scales has led to the development of the branch of chemostratigraphy.Chemostratigraphic study of sedimentary sequences commenced from recognizing identical/contrasting geochemical features across major geochronological boundaries,and evolved into one of the essential tools in exploration,characterization,and well development strategies.Chemostratigraphy incorporates applications on continuous,real-time geochemical mapping and direction of lateral drilling,and machine learning,among others.As the sedimentary systems operate on a variety of temporal scales that range from few hours(tidal cycles)to few tens of millions of years,within which many perturbations such as catastrophic and diagenetic events take place,that lead to unique geochemical signature which can be correlated at appropriate spatial and temporal scales.The application of chemostratigraphic technique in hydrocarbon exploration and reservoir characterization has gained momentum in recent years,particularly with the advent of developments in analytical instrumentation.This has also led to the integration of a variety of data from field sedimentary structures,mineralogy,major,trace and isotopic chemical compositions of whole rock,selected components of rocks,organic and inorganic components of oil and gas,etc.,for reservoir characterization more accurately than ever.The geochemical fingerprinting of oil and gas reservoir components plays a major role in the identification of source rocks,discrimination of oil families,characterization of reservoir,source,and seal segments in petroleum systems.Future trends indicate the relevance and growing applications of machine learning techniques,artificial intelligence in real-time assessment,monitoring and planning of hydrocarbon exploration and production. 展开更多
关键词 BIOMARKER chemostratigraphy Geochemical fingerprinting Machine learning Oil family Stratigraphic correlation
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Testing carbonate chemostratigraphy across differentiated ancient shallow-platform environments(Early Kimmeridgian,S Iberia)
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作者 Rute Coimbra Beatriz Marques Federico Oloriz 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第6期2203-2218,共16页
Shallow-platform settings with marked differences in paleoplatform bottom physiography influence the degree of connection with oceanic waters and overall circulation patterns,even when sharing the same palaeoclimatic ... Shallow-platform settings with marked differences in paleoplatform bottom physiography influence the degree of connection with oceanic waters and overall circulation patterns,even when sharing the same palaeoclimatic conditions.Two Kimmeridgian shallow-marine settings have been explored to test the sensitivity and reliability of carbonate chemostratigraphy to detect such differences.An integrated overview of the obtained elemental trends depicted four major facies,shared along specific stratigraphic intervals of both depositional records.Diagenesis obliterated original geochemical signals only throughout the siliciclastics-rich interval,corresponding to the most landward setting.For the remaining facies,elemental features could be attributed to the differential action of forcing mechanisms operating along the south-Iberian paleomargin during Kimmeridgian times.The highest degree of continental influence can be recognized by a strong relationship between Fe and Mn for the most proximal setting,which fades out along the mixed carbonate-fine siliciclastic rhythmic deposition in more open settings.A characteristic geochemical signature of progressively more positiveδ^(13)C values and significantly higher Sr content is identified for the interval dominated by biogenic sponge buildups.Such a local response is related to local forcing by upwelling in the surroundings of a coral fringe.The geochemical signature of a hydrothermal origin can be clearly differentiated from the influence of mere terrigenous pulses.Accordingly,the decoupling of Fe and Mn along marginal settings is the clue to detecting major events of palaeogeographic restructuring.Observed temporal variations in Mg content along both studied sections are attributed to tectonic activity influencing nearshore/coastal water masses.By integrating chemostratigraphic information and complementary evidence,the palaeoenvironmental mechanisms promoting differentiated sedimentary records along ancient subtropical,shallow,coastal settings can be disentangled. 展开更多
关键词 PALAEOENVIRONMENT Carbonate chemostratigraphy SHALLOW-WATER carbonates DIAGENESIS KIMMERIDGIAN
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A high-resolution chemostratigraphy of post-Marinoan Cap Carbonate using drill core samples in the Three Gorges area, South China
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作者 Hisatoshi Sato Miyuki Tahata +6 位作者 Yusuke Sawaki Shigenori Maruyama Naohiro Yoshida Degan Shu Jian Han Yong Li Tsuyoshi Komiya 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第4期663-671,共9页
Cap Carbonates overlie the Marinoan Snowball Earth-related glacial diamictite, and possibly record the drastic surface environmental change and biological evolution after the Snowball Earth. We conducted on-land drill... Cap Carbonates overlie the Marinoan Snowball Earth-related glacial diamictite, and possibly record the drastic surface environmental change and biological evolution after the Snowball Earth. We conducted on-land drilling from the Liantuo Formation, through the Nantuo, to the lower Doushantuo Formation in the Three Gorges area of South China to collect fresh, continuous samples in the Three Gorges area. We obtained high-resolution chemostratigraphies of ~13C and 6180 values of carbonates from the topmost part of the Nantuo Formation to the Cap Carbonate, in order to decode the detailed surface environmental change in the shallow marine setting. The δ3C chemostratigraphy possesses some unique characteristics: (1) stable δ13C values as a whole, but ubiquitous low δ13C anomalies through the Cap Carbonate, (2) increase of the δ13C values from -3 to +5‰ across the C2/C3 boundary, (3) no δ13C anomaly between the CI and C2 boundary, and (4) presence of an anomalous high δ13C value (+2.3%0) and a faint positive correlation between δ13C and δ18O values in the C1 unit. Evidence of quite low δ13C anomalies (with a nadir of -41‰), ubiquitous negative δ13C anomalies through the Cap Carbonate, and a high 613C anomaly accompanied with a faint positive correlation between δ13C and δ18O values in the C1 unit supports decomposition and formation of methane hydrate during Cap Carbonate formation. The drastic increase of δ13C values from the upper C2 to C3 units in- dicates enhancement of primary productivity and organic carbon burial, possibly due to high continental fluxes after the Snowball Earth event, evidenced by high Sr isotope values. The increase is restricted to the proximal side of the inner shelf in South China, and the timing of the increase of δ13C values of carbonates is earlier at Three Gorges area than any other area, suggesting that the enhancement of primary productivity started in the proximal environment because of higher continental influxes. The increase in oxygen contents of seawater due to the enhanced primary productivity possibly resulted in the emergence of multicellular animals soon after Cap Carbonate deposition. 展开更多
关键词 Cap Carbonate EDIACARAN Marinoan Snowball Earth Carbon isotope chemostratigraphy Methane hydrate
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Bio-organic Geochemical Characteristics of Gold Deposits in Northwestern Guangxi and Their Metallogenetic Significance
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作者 Zhang Aiyun Xiao Jianxin Weng ChengminDepartment of Geology and Energy Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 1995年第2期54-59,共6页
The gold deposits of Triassic period in the northwestern Guangxi are all located in the marine, fine -grained ,fragmental rock series containing organic matter ,i.e .the distribution districts of black rock series . T... The gold deposits of Triassic period in the northwestern Guangxi are all located in the marine, fine -grained ,fragmental rock series containing organic matter ,i.e .the distribution districts of black rock series . The fine-grained gold deposits occur in organic matter -bearing C, D,E,or D,E divisions of the classical Bouma sequences. The evolution degree of organic matters through oil window stage reached the over -mature degree. Both the bio-sources of the organic matters and the distribution of gold in the organic matters disclose the close association between gold , living beings and organic matters . The thermal evolution of organic matters led to the gold to be activized . migrated and enriched , and finally formed gold deposits in the fault belt and crushed zone of black rock series . 展开更多
关键词 fine-grained disseminated gold deposit bio- organic geochemistry metallogenetic significance northwestern Guangxi.
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Biomanufacturing in Japan:frontier research from 2018 to 2023
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作者 Qing Cao Yangqianhui Zhang +3 位作者 Runyi Deng Kai Ren Huayong Yang Dong Han 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第6期617-645,共29页
Biomanufacturing(BM)is a multidisciplinary area incorporating the characteristics of living organisms and engineering principles to create valuable products for various sectors,including medicine,energy,and the enviro... Biomanufacturing(BM)is a multidisciplinary area incorporating the characteristics of living organisms and engineering principles to create valuable products for various sectors,including medicine,energy,and the environment.BM has undergone a remarkable transformation in the last two decades,entering the era of BM4.0 and becoming a pivotal driver of the sustainable revolution.Notably,Japan has made significant advances in BM,contributing to its development through the creation of innovative materials,advanced processes,and interdisciplinary applications.However,because of certain development policies,this research has not been widely recognized on an international level.This paper provides a comprehensive summary of the research progress made by renowned Japanese laboratories and researchers in biomedical materials,bio-three-dimensional(3D)printing,and biomedical applications in the last five years.Their unique contributions are introduced and analyzed,illuminating the distinctive approaches and breakthroughs within each domain.Additionally,this review highlights the current challenges and prospects of BM.The viewpoints presented in this paper are intended to serve as a valuable reference for scholars studying BM in Japan. 展开更多
关键词 Biomanufacturing(BM) JAPAN Biomedical materials bio-3D printing Biomedical applications
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湖北宜昌峡东地区震旦系层型剖面化学地层特征及其国际对比 被引量:41
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作者 王自强 尹崇玉 +1 位作者 高林志 柳永清 《地质论评》 CAS CSCD 北大核心 2002年第4期408-415,共8页
全球末元古系建系研究是当前国际地层学研究的重要课题之一。我国宜昌峡东地区震旦系沿江剖面研究历史悠久,已有相当深入的岩石地层、生物地层及层序地层研究,并被推荐为国际末元古系候选层序剖面之一。为进一步提高其研究精度,本文系... 全球末元古系建系研究是当前国际地层学研究的重要课题之一。我国宜昌峡东地区震旦系沿江剖面研究历史悠久,已有相当深入的岩石地层、生物地层及层序地层研究,并被推荐为国际末元古系候选层序剖面之一。为进一步提高其研究精度,本文系统地研究了震旦系沿江剖面碳酸盐岩同位素化学地层。研究结果表明,陡山沱组底部“碳酸盐岩帽”的δ^(13)C为-3.1‰~-3.7‰,向上为正偏移,至层序Ⅲ(DS3)最大值达+6.7‰。陡山沱组顶部(DS6)再次出现负偏移-2.5‰,构成一个完整的变化周期。同时,^(87)Sr/^(86)Sr值表现出向上增大的变化,由陡山沱组底部(DS1)的0.707743逐渐增高至陡山沱组顶部(DS6)的0.707965;灯影组蛤蟆井段(DS7)的δ^(13)C值变化在-2.5‰~+5‰之间(DS8),至石板滩段中部再次降至+1.7‰(DS10),而后基本保持在+1.7‰~3.6‰之间平稳变动。白马沱段顶部δ^(13)C再次降至+0.5‰,并有向负偏移的趋势。灯影组的^(87)Sr/^(86)Sr值依然出现由老至新递增的趋势(0.708244~0.708993)与当前国际末元古系剖面的化学地层特征基本一致。 展开更多
关键词 湖北 峡东地区 震旦系 屋型剖面 锶同位素 化学地层 冰期
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三峡地区震旦系碳酸盐岩碳氧同位素特征 被引量:29
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作者 陈孝红 李华芹 +2 位作者 陈立德 王传尚 汪啸风 《地质论评》 CAS CSCD 北大核心 2003年第1期66-73,共8页
本文对三峡地区秭归庙河陡山沱组第一段至第三段、宜昌棺材崖陡山沱组第三段上部至灯影组底部以及四溪灯影组石板滩段和白马沱段碳酸盐岩碳氧同位素组成特点的研究结果表明,三峡地区震旦系碳同位素组成与全球新元古代广布的后Marinoan... 本文对三峡地区秭归庙河陡山沱组第一段至第三段、宜昌棺材崖陡山沱组第三段上部至灯影组底部以及四溪灯影组石板滩段和白马沱段碳酸盐岩碳氧同位素组成特点的研究结果表明,三峡地区震旦系碳同位素组成与全球新元古代广布的后Marinoan冰期地层δ^(13)C的分布模式基本一致。本文还讨论了地层中碳同位素组成与生物演化和地层层序发展的关系,指出陡山沱组一段白云岩中δ^(13)C的负异常可以作为震旦系底界划分的标志,最晚Varanger冰期在三峡地区由陡山沱组三段上部出现的三级层序界面所替代,震旦系内部陡山沱组一段和三段可能形成于Marinoan冰期之后,伊迪卡拉生物分异发展之前,而陡山沱组四段及上覆灯影峡组则大致与国外伊迪卡拉期地层对比。 展开更多
关键词 碳酸盐岩 震旦系 化学地层 Marinoan冰期 氧同位素 三峡地区 碳同位素
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用化学地层学研究新元古代地层划分和对比 被引量:25
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作者 王自强 尹崇玉 +3 位作者 高林志 柳永清 唐烽 张传恒 《地学前缘》 EI CAS CSCD 北大核心 2006年第6期268-279,共12页
随着传统地层学向多学科相互渗透的综合地层学方向的发展,笔者开展了湖北峡东地区新元古界震旦系和南华系的化学地层学研究。分别介绍了碳酸盐岩地层的稳定同位素和碎屑岩化学蚀变指数的研究方法和成果并依此提出新元古界划分和对比方... 随着传统地层学向多学科相互渗透的综合地层学方向的发展,笔者开展了湖北峡东地区新元古界震旦系和南华系的化学地层学研究。分别介绍了碳酸盐岩地层的稳定同位素和碎屑岩化学蚀变指数的研究方法和成果并依此提出新元古界划分和对比方案。震旦系碳酸盐岩中所获得的δ^13C变化曲线和^87Sr/^86Sr比值与世界诸多剖面的变化曲线基本一致。南华系碎屑岩的化学蚀变指数(CIA)的特征是莲沱组下部CIA值为55-65(代表寒冷环境的CIA值),莲沱组上部CIA值则增至65~75(代表温湿环境),而莲沱组顶部两个样品的CIA值再次降为寒冷指数60-65;南沱组CIA值均为60-65,除了顶部(接近震旦系)的两个样品分别为69.4和70.9。上述CIA值的变化表明南华系以寒冷气侯为主,并且经历过“寒冷-温湿-寒冷”气候的演变条件下的沉积物。沉积相的多样性说明即使在“冰期”期间古构造、古地理环境对沉积物特征的影响依然存在。 展开更多
关键词 南华系 震旦系 化学地层学 Sr和C同位素 化学蚀变指数
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南非陆相二叠系—三叠系界线研究进展 被引量:5
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作者 彭元桥 高勇群 +2 位作者 杨逢清 殷鸿福 G.R.Shi 《地质科技情报》 CAS CSCD 北大核心 2006年第1期1-8,共8页
从岩石地层研究着手,介绍了南非卡鲁盆地内综合地层研究的相关成果。在生物地层方面,脊椎动物和植物化石的研究在该区具有传统优势,孢粉化石的研究则是在最近几年才取得较大进展,在陆相界线地层研究中菌孢化石在二叠系—三叠系界线处约... 从岩石地层研究着手,介绍了南非卡鲁盆地内综合地层研究的相关成果。在生物地层方面,脊椎动物和植物化石的研究在该区具有传统优势,孢粉化石的研究则是在最近几年才取得较大进展,在陆相界线地层研究中菌孢化石在二叠系—三叠系界线处约1 m厚的地层内的富集事件属首次报道。在地球化学地层方面,南非有机碳同位素在二叠系—三叠系界线附近的变化趋势与海相二叠系—三叠系界线地层存在相似的对应关系,可以作为海、陆相界线地层对比的辅助标志。在磁性地层方面,南非卡鲁盆地内的磁极性存在从反向到正向然后再反转(R-N-R)的变化,二叠系—三叠系界线则位于第一反向极性带的顶部。同时,结合目前全球陆相二叠系—三叠系界线的研究现状及特点,分析了陆相界线地层研究中存在的基本问题,指出华南地区可能为突破传统观念的研究地区,陆地事件地层研究意义重大。 展开更多
关键词 南非卡鲁盆地 陆相二叠系-三叠系界线 生物地层 地球化学地层 磁性地层 事件地层
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滇东北DD1井五峰组—龙马溪组地层界线划分及沉积环境演变 被引量:6
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作者 冯伟明 李嵘 +4 位作者 赵瞻 余谦 杨瀚 谢渊 叶定南 《中国地质》 CAS CSCD 北大核心 2021年第1期297-308,共12页
DD1井上奥陶统临湘组泥灰岩之上发育大套粉砂质泥岩,笔石化石缺乏,也未发现观音桥段含赫南特贝灰岩标志层,O-S界线通过生物地层和岩石地层方法难以确定。微量、稀土元素分析表明,粉砂质泥岩中部(1288.3 m)的Th、Sr、Y、Th/U以及Cen、Eu... DD1井上奥陶统临湘组泥灰岩之上发育大套粉砂质泥岩,笔石化石缺乏,也未发现观音桥段含赫南特贝灰岩标志层,O-S界线通过生物地层和岩石地层方法难以确定。微量、稀土元素分析表明,粉砂质泥岩中部(1288.3 m)的Th、Sr、Y、Th/U以及Cen、Eun、δCe、δEu曲线均呈现尖锐的异常峰,该处ΣREE含量显著高于上下地层,REE分布曲线右倾斜率更大。将DD1井与扬子地区其他O-S界线剖面的元素地球化学特征进行对比分析,可判断DD1井存在五峰组观音桥段,该标志层的厚度也小于1 m。微量元素地球化学氧化-还原判别图还表明,五峰期—龙马溪期早期沉积水介质主要处于弱氧化环境,观音桥期氧化性达到最强;根据沉积学标志分析,O-S之交沉积相演变过程为:潮下→潮间→潮上→潮间,在观音桥期水体最浅,为潮上带沉积。 展开更多
关键词 五峰组 观音桥段 奥陶系—志留系界线 化学地层 滇东北 油气地质调查工程
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广西横县六景泥盆系艾菲尔阶—吉维特阶之交化学地层研究 被引量:2
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作者 刘疆 白志强 《地质论评》 CAS CSCD 北大核心 2008年第5期683-693,I0004,共12页
内容提要:广西横县六景泥盆系剖面艾菲尔阶—吉维特阶界线(Eifelian—Givetian界线)附近的Polygnathus xylus ensensis至下varcus带之间,出现了一系列Ce/La值、Ni/La值和δ^(13)C_(carb)值重大组合性异常,分别代表缺氧事件、Ni事件和生... 内容提要:广西横县六景泥盆系剖面艾菲尔阶—吉维特阶界线(Eifelian—Givetian界线)附近的Polygnathus xylus ensensis至下varcus带之间,出现了一系列Ce/La值、Ni/La值和δ^(13)C_(carb)值重大组合性异常,分别代表缺氧事件、Ni事件和生物灾变等地质历史事件。紧邻艾菲尔阶—吉维特阶界线的生物事件与全球性ka(?)k-otomari事件有较好的响应。该地区所处华南地块南侧、古特提斯洋离散边界附近的古陆缘浅海为上述事件的古地理、古大地构造背景。该系列事件的原始诱因为系列构造运动的不同阶段和不同表现方式:断裂和火山热液活动造成Ni事件;挤压变形和抬升运动耦合相对海平面变化造成缺氧事件。Ni事件和缺氧事件均可独立造成生物灾变事件,而前二者的叠加将使生物灾变加剧,因灾变机制的区域性而未造成生物的大规模灭绝。Ni事件是由洋源性构造、热液和火山活动所主导的。 展开更多
关键词 中泥盆统 艾菲尔阶 吉维特阶 界线 化学地层 事件 广西 六景
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广西横县六景中泥盆统Mg、Ca、Na、Sr、δ^(13)C和δ^(18)O化学地层学特征 被引量:3
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作者 刘疆 白志强 《物探与化探》 CAS CSCD 北大核心 2009年第4期417-423,共7页
广西横县六景中泥盆统的Mg、Ca、Sr、Na、1δ3C和1δ8O化学地层特征清晰地量化了该剖面的岩相及其变化规律,并在生物地层框架内,使该剖面的高精度划分和高精度区域性对比成为可能。化学地层数据与该剖面的沉积相和生物相之间存在良好的... 广西横县六景中泥盆统的Mg、Ca、Sr、Na、1δ3C和1δ8O化学地层特征清晰地量化了该剖面的岩相及其变化规律,并在生物地层框架内,使该剖面的高精度划分和高精度区域性对比成为可能。化学地层数据与该剖面的沉积相和生物相之间存在良好的对应关系,显示那叫期的中泥盆统段为滩后泻湖与蒸发滩3次交替沉积环境;民塘期至谷闭初期为碳酸盐礁滩后斜坡沉积环境。那叫组白云岩的化学地层数据显示不能简单排除白云岩的化学地层学研究价值,可以对成岩作用较弱的细晶、粉晶白云岩,尤其薄层、纹层白云岩开展适度的化学地层学研究。 展开更多
关键词 广西 六景 中泥盆统 Mg CA SR NA δ13C δ18O 化学地层
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多道X射线荧光方法在现代地层学研究中的初步应用
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作者 朱创业 丁益民 +1 位作者 熊晓春 何政伟 《中国区域地质》 CSCD 2000年第2期205-209,221,共6页
放射性同位素多道X荧光分析是一种核分析方法 ,具有快速、无损、低成本及多元素分析等优点。以华蓥山地区庙坝下三叠统嘉陵江组剖面为例 ,采用放射性同位素多道X荧光分析方法 ,测定了地层中Ca、Fe、Sr、Ba元素的照射率 ,并进行了化学地... 放射性同位素多道X荧光分析是一种核分析方法 ,具有快速、无损、低成本及多元素分析等优点。以华蓥山地区庙坝下三叠统嘉陵江组剖面为例 ,采用放射性同位素多道X荧光分析方法 ,测定了地层中Ca、Fe、Sr、Ba元素的照射率 ,并进行了化学地层和层序地层的初步研究 ,取得了较好的效果。 展开更多
关键词 化学地层学 层序地层学 地层学 多道X射线荧光
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鲁中南上前寒武系土门群的时代归属问题 被引量:2
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作者 宋子新 王战 《西安地质学院学报》 1993年第2期22-30,共9页
本文通过对鲁中南上前寒武系土门群地质特征的研究,确定了土门群各组的时代归属,并应用数学地质方法划分了化学地层,进而通过苏皖北部和辽南上前寒武系的对比,阐明了晚前寒武纪华北地块东南缘的古构造环境。
关键词 前寒武纪 土门群 华北地块 时代
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广西桂林南边村剖面泥盆系-石炭系界线化学地层学 被引量:4
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作者 吴一超 白志强 +2 位作者 常洁琼 王宝鹏 孙永超 《地质科技情报》 CAS CSCD 北大核心 2014年第5期86-92,共7页
广西桂林南边村剖面作为全球泥盆系-石炭系界线辅助层型剖面,在界线处的δ13 C值、δ18 O值、w(Ni)、w(Al2O3)等都出现一定程度的突变,这为该剖面的高精度地层划分和对比提供了可能性。南边村剖面和黄茆剖面的化学地层学对比显示黄茆剖... 广西桂林南边村剖面作为全球泥盆系-石炭系界线辅助层型剖面,在界线处的δ13 C值、δ18 O值、w(Ni)、w(Al2O3)等都出现一定程度的突变,这为该剖面的高精度地层划分和对比提供了可能性。南边村剖面和黄茆剖面的化学地层学对比显示黄茆剖面长顺页岩的时代应相当于南边村剖面第56层至第60层,而牙形石演化的证据表明南边村剖面的第56层底部为泥盆系-石炭系界线,因此黄茆剖面的泥盆系-石炭系界线应位于长顺页岩底部。Hangenberg事件作为一次泥盆纪-石炭纪之交的全球性事件,在斜坡相的南边村剖面上也有一定的表现,例如w(Al2O3)上升所代表的海退,δ13C值下降代表的生物灭绝事件,以及Ni异常事件。 展开更多
关键词 南边村剖面 化学地层学 泥盆系-石炭系界线 Hangenberg事件
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秦皇岛石门寨亮甲山奥陶系剖面化学地层和旋回地层研究 被引量:9
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作者 马坤元 李若琛 龚一鸣 《地学前缘》 EI CAS CSCD 北大核心 2016年第6期268-286,共19页
根据秦皇岛石门寨亮甲山奥陶系剖面的化学地层和岩石地层特征,将亮甲山组(O1l)细分为下、中、上段。选取Fe/Ca、Ti/Ca作为古气候替代指标,开展时间序列分析。通过多窗谱法(MTM)和傅里叶变换法(FT),从Fe/Ca、Ti/Ca比值中共提取出... 根据秦皇岛石门寨亮甲山奥陶系剖面的化学地层和岩石地层特征,将亮甲山组(O1l)细分为下、中、上段。选取Fe/Ca、Ti/Ca作为古气候替代指标,开展时间序列分析。通过多窗谱法(MTM)和傅里叶变换法(FT),从Fe/Ca、Ti/Ca比值中共提取出两个明显的米兰科维奇旋回:长偏心率405ka和短偏心率90ka。基于长偏心率周期建立的天文年代标尺表明,亮甲山组沉积时长为6.2Ma,平均沉积速率为14.68m/Ma,其中亮甲山组下段(0.00~48.00m)和中-上段(48.00~91.00m)的沉积速率分别为12.00m/Ma和19.55m/Ma;马家沟组下部的沉积速率为18.00m/Ma。奥陶纪生物大辐射可能直接导致碳酸盐生产模式由以灰泥生产为主转变为以生物碎屑生产为主,并使亮甲山组下段与中-上段之交碳酸盐沉积速率大幅增加。旋回地层分析显示,早、中奥陶世之交天文轨道周期变化引起的地球气候改变可能对奥陶纪生物大辐射有重要的调控作用。 展开更多
关键词 旋回地层 化学地层 X射线荧光光谱分析仪(XRF) 亮甲山组 奥陶纪 奥陶纪生物大辐射 华北秦皇岛
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论陡山沱组的年代(英文) 被引量:34
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作者 安德鲁.诺尔 肖书海 《微体古生物学报》 CSCD 北大核心 1999年第3期225-236,共12页
三峡地区震旦系的三层式地层结构 (冰积层 ,陡山沱组特色的大型带刺疑源类组合层 ,埃迪卡拉生物化石层 )在世界其它地区是常见的。通过生物和化学地层对比我们认为陡山沱组及其化石组合层是在马雷诺恩 ( Marinoan)冰期之后、埃迪卡拉生... 三峡地区震旦系的三层式地层结构 (冰积层 ,陡山沱组特色的大型带刺疑源类组合层 ,埃迪卡拉生物化石层 )在世界其它地区是常见的。通过生物和化学地层对比我们认为陡山沱组及其化石组合层是在马雷诺恩 ( Marinoan)冰期之后、埃迪卡拉生物群分异之前沉积的。根据这一地层对比方案以及西伯利亚、纳米比亚和阿瓦龙半岛 ( Avalon Peninsula)新元古代地层的精确放射性同位素测年资料 ,陡山沱组的沉积年龄很可能在五亿五千万年至六亿年之间。这一估计要新于以前发表的铷锶法或钾氩法测定的陡山沱组黑色页岩或海绿石年龄。更精确地估算陡山沱组的沉积年龄还有待于在陡山沱组地层中发现火山灰以及对火山灰的精确年龄测定 ,但我们根据地层对比估算的陡山沱组年龄 ,为评估庙河和瓮安陡山沱组生物群的演化意义提供了必要的地层框架。 展开更多
关键词 埃迪卡拉 生物化石 生物地层 末元古代 陡山沱组
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