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Journal of Earth Science 2016年第2期27卷 225-232页

作者： lianjun feng Qirui Zhang Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Institute of Geology and Geophysics Chinese Academy of Sciences

The Dajiangbian Formation in South China is a siliciclastic-dominated sedimentary succession with low-grade metamorphism deposited on the western margin of the Cathaysia Block, and is capped by a glaciogenic diamictite（the Sizhoushan Formation）. The Sizhoushan glaciogenic strata can be attributed to the Jiangkou glacial（Sturtian glacial） episode as they share stratigraphic and lithological similarities with Jiangkou strata in South China. Some carbonate, chert and shale units throughout the upper part of the Dajiangbian Formation were sampled for carbonate carbon isotope（δ^（13）C_（carb）） and organic carbon isotope（δ^（13）C_（org）） analyses. A range of geochemical indices including oxygen isotopes（δ^（18）O） and Mn/Sr（Fe/Sr） ratios suggest that primary carbon isotope values were preserved in the upper Dajiangbian Formation. The upper Dajiangbian Formation shows δ^（13）C_（carb） of-0.1‰, upward decreasing towards to-5.4‰. We suggest that the negative δ^（13）C excursion beneath the Sizhoushan diamictite is correlative with the Pre-Sturtian Islay δ^（13）C_（carb） anomaly and allows correlation with the global Neoproterozoic isotope stratigraphy. We find that carbonate and organic carbon isotope data of the upper Dajiangbian Formation are coupled, consistent with the δ^（13）C_（carb）-δ^（13）C_（org） pattern observed on multiple continents.

关键词： Neoproterozoic Cryogenian carbon isotopes Islay anomaly Cathaysia Block.

音频大地电磁法和氡气测试在某地热勘察中的应用

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勘察科学技术 2024年第4期 59-64页

作者：李彬冯连军沈伟新四川省地质工程勘察院集团有限公司四川省地质局第一地质大队

近年来，音频大地电磁法和土壤氡气测试，在大深度地质及区域构造调查领域内取得了优异的勘探效果。该文介绍了应用音频大地电磁法和氡气测试法两种手段对川西某地热构造进行探测的实例，通过数据处理及解译，综合分析判断，查明了该岩... 详细信息

近年来，音频大地电磁法和土壤氡气测试，在大深度地质及区域构造调查领域内取得了优异的勘探效果。该文介绍了应用音频大地电磁法和氡气测试法两种手段对川西某地热构造进行探测的实例，通过数据处理及解译，综合分析判断，查明了该岩浆岩地区地热分布情况，经钻探验证，成功开采出地热水。该实例表明，音频大地电磁法和氡气测试法，在地热勘察中具有较高的实用和推广价值。

关键词：音频大地电磁法土壤氡气测试岩浆岩地热勘探地质构造

Terminal Ediacaran anoxia in deep-ocean: Trace element evidence from cherts of the Liuchapo Formation, South China

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Science China Earth Sciences 2009年第6期52卷 807-822页

作者： CHANG HuaJin CHU XueLei feng lianjun HUANG Jing State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China

Here we report a detailed trace element study of the cherts from Liuchapo Formation, which is a terminal Ediacaran (551-542 Ma) succession in South China deposited in deep-water basinal setting. The REE of Liuchapo cherts shows similar features as observed for anoxic modern seawater (but not for hydrothermal fluids), characterized by positive La anomaly (LaN/CeN = 0.83–1.91, average 1.37), moderately negative Ce anomaly (0.53–1.1, average 0.73), positive Gd anomaly (average 1.08), positive Y anomaly (average 1.21), and depleted LREE and MREE. In addition, the Liuchapo cherts have low ΣREE (3.36–56.13 ppm, average 20.6 ppm), low Al2O3, Ti, Th and Zr concentrations, and high Y/Ho ratios (up to 43.9). The redox-sensitive trace elements concentrations in the cherts do not correlate with detrital input proxies. All of these features suggest that the redox-sensitive trace elements in the cherts were authigenically concentrated in water column and their concentrations thus are excellent indicators of ancient redox conditions. Very low Th/U ratios, high V/(V+Ni) and Fe?/Al ratios, enrichments of redox-sensitive trace elements (U, V, Mo), and low concentration of Mn in the cherts imply anoxia in the deep seawater. Our data reveal that the terminal Ediacaran ocean was not completely oxidized and the deep ocean was still anoxic, at least in South China. We propose that although the oxidative events existed in the terminal Ediacaran oceans, decomposition of organic matter prolonged anoxia in the deep ocean.

关键词： chert anoxia trace elements redox proxy Ediacaran South China

Discussion on the Neoproterozoic glaciations in the South China Block and their related paleolatitudes

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Chinese Science Bulletin 2009年第10期54卷 1797-1800页

作者： ZHANG QiRui CHU XueLei feng lianjun State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029China

The Kaigas, Sturtian, Marinoan, and Gaskiers glaciations are widely recognized in Neoproterozoic. However, in the South China Block only the Jiangkou (Sturtian) and Nantuo (Marinoan) are symbolized by sedimentary records. The Kaigas, recorded by isotopic and chemical proxies, exhibited likely the nature of cold paleoclimate with local mountain glaciation. The correlation of the Doushantuo Formation with the Gaskiers is indicated by the carbon isotope excursion and the dated age from the interval, however the South China Block was then under non-glacial weather. With no paleomagnetic data, the position of the South China Block during the Sturtian glaciation cannot be determined. The paleolatitudes of the South China Block during the Kaigas and Nantuo glaciations are intermediate, even though the Nantuo was once rendered erratically deduced equatorial. In fact, the paleolatitudes of the South China Block during the Neoproterozoic glaciations are all likely at about 30°―40°.

关键词：冰期气候新元古代中国碳同位素古地磁数据沉积记录寒冷气候时间间隔

Iron speciation in cherts from the Laobao Formation,South China:Implications for anoxic and ferruginous deep-water conditions

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Chinese Science Bulletin 2010年第27期55卷 3189-3196页

作者： CHANG HuaJin CHU XueLei feng lianjun HUANG Jing School of Life and Geography Sciences Qinghai Normal University Xining 810008 China Key Laboratory of Tibetan Plateau Environment and Resources Ministry of Education Xining 810008 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Cherts in the Laobao Formation in the Silikou section,South China were deposited in terminal Ediacaran *** speciations of iron in cherts,such as pyrite Fe(FeP),HCl-extractable Fe(FeH),and total Fe(FeT),and their interrelationships,are proxies for distinguishing oxic,anoxic but ferruginous,and sulfidic conditions,which is an effective method for studying the terminal Ediacaran ocean *** chert samples from the Laobao Formation,pyrite concentrations are generally low(<0.56%),degree of pyritization(DOP)ranges from<0.01 to 0.78 and most are<0.45;(FeP+FeH)/FeT ratios are between 0.27 and 0.84 and most exceed 0.38,and most of FeT/Al ratios range from 0.55 to 5.87(averaging 1.1).Relatively high content of highly reactive Fe and low content of pyrite indicate a scarcity of H2S and Fe-enriched *** features suggested that the deposition setting of Laobao cherts was anoxic and *** Ediacaran deep-water in the South China Basin was most likely anoxic and ferruginous,which played a key role in the emergence and evolution of early multicellular life.

关键词：深水条件硅质岩铁质缺氧中国 o形形态场效应晶体管

Genesis of Silica-phosphatic Nodules with Small Shelly Fossils Preserved in the Lowermost Cambrian of South China

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1294-1307页

作者： QIU Hao feng lianjun CHU Xuelei LI Luoyang ZHANG Xingliang LI Jinhua Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China State Key Laboratory of Continental Dynamics and Shaanxi Key Laboratory of Early Life and Environments Department of GeologyNorthwest UniversityXi’an 710069China

Silica-phosphatic nodules are abundant in black shales of the Yanjiahe Formation in the Three Gorges Area of South China,which is correlated to the Fortunian Stage,Terreneuvian Series,Cambrian *** nodules are rich in small shelly fossils and hence attract the attention of numerous paleontologists and sedimentary ***,the genesis of the nodules and the preservation of the small shelly fossils are poorly *** we analyze morphological,structural,mineralogical and chemical features of the nodules in multiscale using a combination of micro-X-ray fluorescence spectroscopy,X-ray diffraction,scanning electron microscopy and confocal laser Raman *** reveal that nodules are concentric in chemical and mineralogical compositions,comprising a silica-phosphatic core encrusted sequentially by a phosphatic zone,a siliceous zone and a very thin pyrite outer *** black shales hosting the nodules demonstrate a laminated texture of alternating clayey and silty laminae,which were respectively deposited in sulfidic/less sulfidic,high/low production,intense/weak chemical weathering *** phosphogenesis of the nodules resulted in the phosphatization of small shelly fossils,which prevented the fossils from being dissolved during diagenesis,whereas the silica encrustation sealed the fossils within the nodules and thus protected the fossils from alteration by deep burial and surface weathering.

关键词： silica-phosphatic nodule small shelly fossils Yanjiahe Formation taphonomy Cambrian

Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, China

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Science China Earth Sciences 2004年第2期47卷 160-170页

作者： CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, feng lianjun & ZHANG Fusong1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Key Laboratory for Mineral Resources Research, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Chu Xuelei (email: xlchu@***) 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Key Laboratory for Mineral Resources Research Chinese Academy of Sciences 100029 Beijing China

Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13C values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2±2)‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13C values of carbonates increase from about -3‰ to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13C value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13C value occurring from the ages of ca. 1700 to ca. 1600 Ma and ＜1300 Ma may signify two correlative global tectonic events.

关键词： Proterozoic, Jixian, carbon isotope, chemostratigraphy, secular variation, global tectonic event.

Variations of sulfur and carbon isotopes in seawater during the Doushantuo stage in late Neoproterozoic

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Chinese Science Bulletin 2003年第13期48卷 1375-1380页

作者： ZHANG Tonggang, CHU Xuelei, ZHANG Qirui, feng lianjun & HUO Weiguo Key Lab of Mineral Resources Exploration and Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Key Lab of Mineral Resources Exploration and Research Institute of Geology and Geophysics Chinese Academy of Sciences China

Successive analyses of sulfur and carbon isotopic compositions of carbonates strata in the Doushantuo Formation in the Yangtze area were accomplished through a method of extracting trace sulfate from carbonates. Sulfur and carbon isotopic compositions of coeval seawater were estimated from the samples that show the least diagenetic alteration. A high-resolution age curve of sulfur isotopes in seawater sulfates was obtained in the Doushantuo stage, which reflects the trend of variation in seawater sulfur isotopes after the Neoproterozoic snowball Earth event. Similar characteristics of variation in carbon isotopes were observed in the coeval carbonates. A large positive d 34S excursion over +20?occurs in ancient seawater sulfates in the early Doushantuo stage. Simultaneously, the d 13C values in ancient seawater carbonates exhibit a positive excursion up to 10. The maximum d 34S and d 13C values are +46.4 and +6.9? respectively. In the middle Doushantuo stage, the range of variation in d 34S values of seawater is relatively narrow, but d 13C values are quite high. Then, d 34S values of seawater become oscillating, and the same occurs in d 13C values. Negative excursions in d 34S and d 13C values occur simultaneously at the end of the Doushantuo stage, and the minimum d 34S and d 13C values dropped down to -10.1 and -5.7? respectively. The characteristics of variations in the sulfur and carbon isotopes of ancient seawater imply strong changes in oceanic environment that became beneficial to inhabitation and propagation of organism. The organic productivity and burial rate of organic carbon once reached a quite high level during the Doushantuo stage. However, the state of environment became unstable after the global glaciation. The global climate and environment possibly were fluctuating and reiterating. The negative excursions in d 34S and d 13C values occurring at the end of the Doushantuo stage may represent a global event, which might be related to oxidation of dee

关键词：硫碳同位素分馏新元古代成岩作用

习近平调查研究重要论述的逻辑理路与实践指向

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理论视野 2021年第4期254卷 34-40页

作者：冯连军湖北经济学院马克思主义学院

调查研究是我们党的传家宝,是我们做好各项工作的基本功。进入新时代,习近平科学谋划和部署党和国家事业发展全局,对调查研究作出一系列重要论述,系统回答了“新时代为什么要重视调查研究、怎样进行调查研究”等重大理论和实践问题,不... 详细信息

调查研究是我们党的传家宝,是我们做好各项工作的基本功。进入新时代,习近平科学谋划和部署党和国家事业发展全局,对调查研究作出一系列重要论述,系统回答了“新时代为什么要重视调查研究、怎样进行调查研究”等重大理论和实践问题,不仅明确了新时代调查研究的逻辑理路,也为顺利推进社会主义现代化建设事业提供了科学的方法论指导。新时代深入开展调查研究,要始终坚定人民立场,坚持问题导向性,与时俱进创新方法举措,推进调查研究制度化经常化。

关键词：习近平新时代调查研究逻辑理路治国理政

莲沱砂岩——南华大冰期前气候转冷的沉积记录

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岩石学报 2006年第9期22卷 2387-2393页

作者：冯连君储雪蕾张同钢黄晶中国科学院地质与地球物理研究所

湖北宜昌地区出露的莲沱组中上部细屑岩的化学蚀变指数(CLA)介于60～70之间,表明是在寒冷干燥的气候条件下沉积的。比较莲沱组与板溪群中下部沉积岩的主化学成分和 CIA 值表明,板溪群源区遭受过强烈的化学风化,相应的古气候是温暖湿润的... 详细信息

湖北宜昌地区出露的莲沱组中上部细屑岩的化学蚀变指数(CLA)介于60～70之间,表明是在寒冷干燥的气候条件下沉积的。比较莲沱组与板溪群中下部沉积岩的主化学成分和 CIA 值表明,板溪群源区遭受过强烈的化学风化,相应的古气候是温暖湿润的,而莲沱组源区化学风化弱,可见两者形成时的古气候环境明显不同。根据 CIA 值推测,地层层序上莲沱组位于板溪群的中上部,莲沱砂岩的 CIA 研究表明南华大冰期前全球气候已经从温暖湿润转变为寒冷干燥,CIA 值继续降低预示着全球性的冰期到表,不久就发生了"雪球地球"事件。

关键词：新元古代扬子地台莲沱组化学蚀变指数寒冷气候古城(江口)冰期