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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.

Research status, hot spots, difficulties and future development direction of microbial geoengineering

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Journal of Road Engineering 2024年第2期4卷 234-255页

作者： Yingxin Zhou Zhiqing Li Peng Zhang Qi Wang Weilin Pan Shuangjiao Wang Xiongyao Xie Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Yunnan Communications Investment&Construction Group Co. Ltd.Kunming 650103China Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Science University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China China Energy Technology and economics Research Institute Beijing 102211China Cangzhou Qugang Expressway Construction Co. Ltd.Cangzhou 062450China Henan Yelu Expressway Construction Co. Ltd.Pingdingshan 467000China Beijing Zhongyan Tiandi Technology Co. Ltd.Beijing 100029China

Microbial geoengineering technology,as a new eco-friendly rock and soil improvement and reinforcement technology,has a wide application prospect.However,this technology still has many deficiencies and is difficult to achieve efficient curing,which has become the bottleneck of large-scale field application.This paper reviews the research status,hot spots,difficulties and future development direction microbial induced calcium carbonate precipitation(MICP)technology.The principle of solidification and the physical and mechanical properties of improved rock and soil are systematically summarized.The solidification efficiency is mainly affected by the reactant itself and the external environment.At present,the MICP technology has been preliminarily applied in the fields of soil solidification,crack repair,anti-seepage treatment,pollution repair and microbial cement.However,the technology is currently mainly limited to the laboratory level due to the difficulty of homogeneous mineralization,uneconomical reactants,short microbial activity period and large environmental interference,incidental toxicity of metabolites and poor field application.Future directions include improving the uniformity of mineralization by improving grouting methods,improving urease persistence by improving urease activity,and improving the adaptability of bacteria to the environment by optimizing bacterial species.Finally,the authors point out the economic advantages of combining soybean peptone,soybean meal and cottonseed as carbon source with phosphogypsum as calcium source to induce CaCO3.

关键词： Microbial geoengineering Microbial induced calcium carbonate precipitation Bacillus pasteurii Urease Phosphogypsum

Oxygenation in carbonate microbialites and associated facies after the end-Permian mass extinction:Problems and potential solutions

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Journal of Palaeogeography 2018年第1期7卷 32-47页

作者： Stephen Kershaw Hao Tang Yue Li Li Guo Department of Life Sciences Kingston Lane Brunel University State Key Laboratory of Oil and Gas Reservoir geology and Exploitation Southwest Petroleum University CAS Key Laboratory of economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences CASP Department of Earth Sciences University of Cambridge

Carbonate sediments deposited in normally-oxygenated shallow ocean waters of the latest Permian period, immediately prior to the end-Permian mass extinction, contain well-developed diverse shelly faunas. After the extinction of these skeletal metazoans, the sediments commonly comprise microbialites(regarded by most authors as benthic) and associated facies bearing evidence interpreted by many authors to indicate reduced oxygenation of the shallow ocean waters. However, the evidence of oxygenation state is inconsistent and the sequences have gaps, indicated in the following 5 points:1) Shelly fossils occur commonly in post-extinction shallow marine limestones, and likely to have been aerated in contact with the atmosphere. Nevertheless, although the largest mass extinction in Earth history may have caused reduced body size in shelly organisms, such reduction is arguably due to environmental stress of lowered oxygenation. Discriminating between these controls remains a challenge.2) Abundant pyrite framboids in many post-extinction limestones are interpreted by several authors as indicating dysoxic contemporaneous waters, so the organisms that lived there, now shelly fossils, were dysaerobic. However, verification is problematic because pyrite framboids scattered amongst shelly fossils cannot have formed amongst living organisms, which need at least some oxygen; synsedimentary framboid formation requires anoxic conditions in the redox boundary where sulphate-reducing processes work. Thus, framboids and shelly fossils found together means taphonomic mixing of sediments, destroying original depositional relationships so that it is not possible to determine whether the shells were aerobic or dysaerobic prior to sediment mixing. Furthermore, diagenetic growth of framboids is possible, as is import of previously-formed framboids from deeper water during upwelling. Thus, there is no proof of an environmental link between framboid size and occurrence, and contemporaneous oxygenation in these post-extinction shallow water f

关键词： Stromatolite Thrombolite Microbialite Permian-Triassic boundary Pyrite Anoxia

鄂西宜昌地区寒武系页岩过剩钡成因及其对有机质富集的指示

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地学前缘 2023年第3期30卷 66-82页

作者：罗欢邵德勇孟康张瑜宋辉闫建萍张同伟兰州大学地质科学与矿产资源学院甘肃省西部矿产资源重点实验室甘肃兰州730000 西北大学地质学系大陆动力学国家重点实验室陕西西安710069 bureau of economic geology The University of Texas at AustinAustin TX 78713USA

通过对鄂西宜昌地区鄂阳页1井(EYY1)寒武系底部岩家河组和水井沱组下部的总有机碳(TOC)、总无机碳(TIC)、微量元素(Ba、U、Th)和稀土元素分析,并结合前人对中上扬子地区7个位于不同沉积环境区寒武系剖面的研究结果和已有数据报道,讨论... 详细信息

通过对鄂西宜昌地区鄂阳页1井(EYY1)寒武系底部岩家河组和水井沱组下部的总有机碳(TOC)、总无机碳(TIC)、微量元素(Ba、U、Th)和稀土元素分析,并结合前人对中上扬子地区7个位于不同沉积环境区寒武系剖面的研究结果和已有数据报道,讨论了寒武系水井沱组富有机质页岩中过剩钡(Ba过剩)的成因、来源及其对海洋古生产力水平的指示。结果表明,中上扬子地区寒武系富有机质页岩普遍富集Ba过剩,而且从浅水内陆棚到深水外陆棚——大陆斜坡,再到热水沉积区,寒武系页岩的Ba过剩富集程度趋于增加,反映了与古陆物源区的距离远近以及古地理背景对Ba过剩富集的控制。寒武系富有机质页岩中所富集的Ba过剩有热液成因和生物成因两种来源,Ba过剩-Eu异常图版可用于推测其主要来源:黔北—湘西北地区所处的热水沉积区内Ba过剩含量极高(>10000μg/g),具有显著的正Eu异常,且Ba过剩与Eu异常值具有正相关性,指示Ba过剩主要为热液成因,其含量变化反映了热液活动的强度;鄂西地区和黔南地区Ba过剩含量相对较高(5000~10000μg/g),四川盆地西部Ba过剩含量相对较低(<1000μg/g),而且都不具备正Eu异常,指示Ba过剩为生物成因,其含量变化与古生产力水平有关。与中上扬子其他地区寒武系页岩的TOC含量、U/Th值及Ba过剩富集程度的综合对比表明,宜昌地区较高的古生产力水平和强还原条件为有机质的来源和保存提供了物质基础和有利条件,共同决定了寒武系水井沱组页岩有机质的富集。

关键词：中上扬子地区寒武系水井沱组鄂阳页1井富有机质页岩过剩钡稀土元素

Dynamic Diurnal Changes in Green Algae Biomass in the Southern Yellow Sea Based on GOCI Images

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Journal of Ocean University of China 2020年第4期19卷 811-817页

作者： JIANG Binbin FAN Daidu JI Qingyuan OBODOEFUNA Doris Chigozie State Key Laboratory of Marine geology Tongji UniversityShanghai 200092China School of Civil Engineering and Geosciences Newcastle UniversityNewcastle Upon Tyne NE31QDUK Institute of Oceanography Zhejiang Geological Institute of China Metallurgical Geology BureauQuzhou 324000China

Macroalgae blooms of Ulva prolifera have occurred every summer in the southern Yellow Sea since 2007,inducing severe ecological problems and huge economic losses.Genesis and secular movement of green algae blooms have been well monitored by using remote sensing and other methods.In this study,green algae were detected and traced by using Geostationary Ocean Color Imager(GOCI),and a novel biomass estimation model was developed from the relationship between biomass measurements and previously published satellite-derived biomass indexes.The results show that the green algae biomass can be determined most accurately with the biomass index of green algae for GOCI(BIGAG),which is calculated from the Rsurf data that had been atmospherically corrected by ENVI/QUAC method.For the first time,dynamic changes in green algae biomass were studied over an hourly scale.Short-term biomass changes were highly influenced by Photosynthetically Available Radiation(PAR)and tidal phases,but less by sea surface temperature variations on a daily timescale.A new parameter of biomass changes(PBC),calculated by the ratio of the biomass growth rate to movement velocity,could provide an effective way to assess and forecast green tide in the southern Yellow Sea and similar areas.

关键词： green algae biomass GOCI BIGAG parameterizing biomass change

Status of China's Mineral Resources in 2013

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Acta Geologica Sinica(English Edition) 2014年第3期88卷 1018-1019页

作者： HAO Ziguo FEI Hongcai HAO Qingqing Susan TURNER Chinese Academy of Geological Sciences Editorial Office of Acta Geologica Sinica (English edition) Geological Society of China Editorial Office of geology and Exploration Institute of Mineral Resources Research China Metallurgical Geology Bureau

On 22nd April 2014,with the approach of the 45th World Earth Day,China＇s Ministry of Land and resources issued the status of China＇s mineral resources in 2013.The first task of the prospecting breakthrough strategy action implemented in the last five years has been completed,and China＇s security capacity for mineral resources has been significantly improved.In the future,the enforcement of the economical and intensive utilization of mineral resources will be strengthened,and economic transformation and upgrading will be promoted to ensure sustained and stable development of China＇s economy.

关键词： mineral resources economic transformation

Lu–Hf constraints on pre-,syn,and post-collision associations of the Gurupi Belt,Brazil:Insights on the Rhyacian crustal evolution

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Geoscience Frontiers 2022年第5期13卷 336-349页

作者： Evandro L.Klein Joseneusa B.Rodrigues Geological Survey of Brazil SBNQuadra 02Bloco HEd.Central Brasília1andarAsa NorteBrasília-DF CEP:70040-904Brazil GPGE–Grupo de Pesquisa em Geologia Econômica(economic geology Research Group) PPGG–Programa de Pós-Graduação em Geologia e GeoquímicaUniversidade Federal do ParáBelém-PABrazil

The Gurupi Belt(together with the São Luís cratonic fragment),in north-northeastern Brazil,has been described in previous studies that used extensive field geology,structural analysis,airborne geophysics,zircon U–Pb dating,and whole-rock Sm–Nd isotope and geochemical data as a polyphase orogenic belt,with the Rhyacian being the main period of crust formation.This was related to a 2240 Ma to 2140 Ma accretionary processes that produced juvenile crust,which has subsequently been reworked during a collisional event at 2100±20 Ma,with little evidence of Archean crust.In this study,we use Lu–Hf isotopic data in zircon from granitoids(including gneiss)of variable magmatic series,and amphibolite to improve the knowledge of this scenario,and investigate additional evidence of recycling of Archean basement.Pre-collisional high Ba-Sr and ferroan granitoids and amphibolite formed in island arc(2180–2145 Ma),show only zircons with suprachondriticεHf values(ca.+1 to+8)indicating the large predominance of juvenile magmas.Only 10%of the data show slightly negativeεHf values(0 to-4),which have been observed in granodiorite-gneiss formed in continental arc(2170–2140 Ma),and in strongly peraluminous collisional granites(2125–2070 Ma),indicating the rework of older Paleoproterozoic to Archean components(Hf_(TDM)=2.11–3.69 Ga).A two-component mixing model using both Hf and published Nd isotope data are in line with this interpretation and indicate more than 90%of juvenile material,and less influence of Archean materials.Comparing with other Rhyacian terranes that are interpreted to have been close to Gurupi in a pre-Columbia configuration(ca.2.0 Ga),our results differ from those of SEGuiana Shield,which show strong influence of Archean protoliths,and are very similar to those of the central-eastern portion of the Baoulé-Mossi Domain of the West African Craton,which has also been formed largely by juvenile magmas in an accretionary-collisional orogen.

关键词： Paleoproterozoic Accretion Collision Isotope geology Lu–Hf isotopes Rhyacian

A New Classification Scheme of Fluorite Deposits

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International Journal of Geosciences 2017年第4期8卷 599-610页

作者： Rajni Magotra Stanzin Namga Pawan Singh Neha Arora P.K. Srivastava economic geology Research Group Department of Geology University of Jammu Jammu India

Fluorite deposits occur in a variety of geologic environments throughout the globe. It may occur as the main or only economically recoverable ore mineral in deposits or may present as the accessory gangue minerals with other ores. It is therefore necessary to understand various genetic types of the fluorite deposit. The present paper synthesises the information of some of the known fluorite mineralisation from the world so that an understanding of them can help in establishing reliable criteria for further search of fluorite deposit. On the basis of a combination of geological background information and fluorite geochemistry, a new classification scheme is proposed.

关键词： Fluorite Classification Genetic Types REE Characteristics

Astronomical tuning and magnetostratigraphy of Neogene biogenic reefs in Xisha Islands, South China Sea

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Science Bulletin 2018年第9期63卷 564-573页

作者： Liang Yi Zhimin Jian Xinyu Liu Youhua Zhu Daojun Zhang Zhenfeng Wang Chenglong Deng State Key Laboratory of Marine geology Tongji University Shanghai 200092 China Laboratory for Marine geology. Qingdao National Laboratory for Marine Science and Technology Qingdao 266061 China China National Offshore Oil Corporation Ltd. Zhanjiang Branch Zhanjiang 524057 China Key Laboratory of economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology. Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Lithospheric Evolution. Institute of geology and Geophysics. Chinese Academy of Sciences Beijing 100029 China Institutions of Earth Science Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences. Beijing 100049 China

Biogenic reefs are one of two major depositional types in the South China Sea, and are constructed by coral, algae and bryozoa. The West Pacific is a major area of biogenic reef development and plays a critical role in the global carbon cycle. However, the lack of geochronological studies in previous works inhibits our understanding of their contributions. Herein, we conduct a cyclostratigraphic and magnetostratigraphic study on Neogene biogenic reefs using the XK–1 core that was drilled at the Shidao Island,Xisha(Paracel) Islands. The main findings of this study are:(1) the establishment of reliable magentostratigraphy for Ledong, Huangliu, Meishan and Sanya Formations;(2) the magnetic susceptibility variation can be inferred as growth index and tuned to the 405–ka long eccentricity cycle;(3) the astronomical geochronology suggests that the bottom ages for Ledong, Yinggehai, Huangliu, Meishan,and Sanya Formations are 2.2 Ma, 5.7 Ma, 10.4 Ma, 16.6 Ma, and 24.3 Ma, respectively; and (4) Earth's eccentricity and obliquity played predominant roles in biogenic reef establishment on orbital to tectonic timescales. Thus, the reported geochronology offers an opportunity to test the contributions of various factors and hypothesize their roles in the global carbon cycle in future.

关键词：晚第三纪华南海礁石生物天体地球年代学调查结果周期