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Light carbon isotope events of foraminifera attributed to methane release from gas hydrates on the continental slope, northeastern South China Sea

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Science China Earth Sciences 2016年第10期59卷 1981-1995页

作者： ZHUANG Chang CHEN Fang CHENG SiHai LU HongFeng WU Cong CAO Jun DUAN Xiao key laboratory of Marine mineral resources Ministry of Land and ResourceGuangzhou Marine Geological Survey

In 2013, the China Geological Survey and Guangzhou Marine Geological Survey conducted the second Chinese gas hydrate expedition in the northern South China Sea （SCS） and successfully obtained visible gas hydrate samples. Five of the thirteen drilling sites were cored for further research. In this work, Site GMGS2-08 is selected for the stable isotopic analy- sis of foraminifera present in the boreholes in order to reveal the carbon isotopic characteristics of the foraminifera and their response to methane release in the gas hydrate geological system. Our results show that the methane content at Site GMGS2-08 is extremely high, with headspace methane concentrations up to 39300 μmol L^-1. The hydrocarbon δ^13C values, ranging from -69.4%o to -72.3‰ PDB, distinctly indicate biogenic generation. Based on the δD analytical results （-183‰ to -185‰ SMOW）, headspace methane is further discriminated to be microbial gas, derived from CO2 reduction. By isotopic measurement, five light δ^13C events are found in the boreholes from Site GMGS2-08, with foraminiferal δ^13C values being ap- parently lower than the normal variation range found in the glacial-interglacial cycles of the SCS. The δ^13C values of benthic Uvigerina peregrina are extremely depleted （as low as -15.85‰ PDB）, while those of planktonic Globigerinoides ruber reach -5.68‰ PDB. Scanning electron micrograph （SEM） studies show that foraminiferal tests have experienced post-depositional alteration, infilled with authigenic carbonate, and the diagenetic mineralization is unlikely to be related to the burial depths. The correlation calculation suggests that the anaerobic oxidation of organic matter has only weak influences on the δ^13C com- position of benthic foraminifera. This means that the anomalous δ^13C depletions are predominantly attributed to the overprint- ing of secondary carbonates derived from the anaerobic oxidation of methane （AOM）. Furthermore, the negative δ^13C anoma- lies, coupled with the positive

关键词： Gas hydrates Carbon isotopes Foraminifera South China Sea Taixinan Basin

Archean Mass-independent Fractionation of Sulfur Isotope:New Evidence of Bedded Sulfide Deposits in the Yanlingguan-Shihezhuang area of Xintai,Shandong Province

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Acta Geologica Sinica(English Edition) 2008年第2期82卷 444-450页

作者： LI Yanhe HOU Kejun WAN Defang YUE Guoliang key laboratory of Metailogeny and mineral resource AssessmentInstitute of mineral resource Chinese Academy of Geological Sciences Beijing 100037 Key Laboratory of Isotope Geology CAGS Beijing 100037

Multiple sulfur isotope ratios （^34S/^33S/^32S） of Archean bedded sulfides deposits were measured in the Yanlingguan Formation of the Taishan Group in Xintai, Shandong Province, East of China; 633S = -0.7%o to 3.8‰,δ^34S = 0.1‰-8.8‰, △^33S = -2.3‰ to -0.7‰. The sulfur isotope compositions show obvious mass-independent fractionation （MIF） signatures. The presence of MIF of sulfur isotope in Archean sulfides indicates that the sulfur was from products of photochemical reactions of volcanic SO2 induced by solar UV radiation, implying that the ozone shield was not formed in atmosphere at that time, and the oxygen level was less than 10-5 PAL （the present atmosphere level）. The sulfate produced by photolysis of SO2 with negative △^33S precipitated near the volcanic activity center; and the product of element S with positive △^33S precipitated far away from the volcanic activity center. The lower △^33S values of sulfide （-2.30‰ to --0.25‰） show that Shihezhuang was near the volcanic center, and sulfur was mostly from sulfate produced by photolysis. The higher △^33S values （-0.5‰ to -‰） indicate that Yanlingguan was far away from the volcanic center and that some of sulfur were from sulfate, another from element S produced by photolysis. The data points of sulfur isotope from Yanlingguan are in a line parallel to MFL （mass dependent fractionation line） on the plot of δ^34S--δ^33S, showing that the volcanic sulfur species went through the atmospheric cycle into the ocean, and then mass dependent fractionation occurred during deposition of sulfide. The data points of sulfur isotope from Shihezhuang represent a mix of different sulfur source.

关键词： Xintai of Shandong Province Archean sulfides sulfur MIF photochemical reaction

Origin and Geological Significance of TTG Gneisses from the Maevatanana Greenstone Belt in North-Central Madagascar,and A Comparison with India

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1003-1024页

作者： LI Peng LI Jiankang LIU Shanbao PEI Rongfu SHI Guanghai key laboratory of Metallogeny and mineral resource Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences State key laboratory of Geological Processes and mineral resources China University of Geosciences

The Maevatanana greenstone belt in north-central Madagascar contains widespread exposures of tonalite-trondhjemite-granodiorite （TTG） gneisses, and is important for its concentrations of various metal deposits （e.g., chromium, niekle, iron, gold）. In this paper we report on the petrography, and major and trace element compositions of the TTG gneisses within the Berere Complex of the Maevatanana area, as well as LA-ICP-MS U-Pb ages and Lu-Hf isotopic compositions of zircons from the gneisses. The gneisses consist mainly of granitoid gneiss and biotite （± hornblende） plagiogneiss, and analysis of thin sections provides evidence of crushing, recrystallization, and metasomatism related to dynamic metamorphism. Samples have large variations in their major and trace element contents, with SiO2 = 55.87-68.06 wt%, Al2O3 = 13.9-17.8 wt%, and Na2O/K2O= 0.97-2.13. Geochemically, the granitoid gneisses and biotite plagiogneisses fall on a low-Al trondhjemite to granodiorite trend, while the biotite-hornblende plagiogneisses represent a high-Al tonalite TTG assemblage. Zircon U-Pb dating shows that the Berere Complex TTG gneisses formed at 2.5-2.4 Ga. Most εHf（t） values of zircons from the biotite （q- hornblende） plagiogneisses are positive, while most εHf（t） values from the granitoid gneisses are negative, suggesting a degree of crustal contamination. Two-stage Hf model ages suggest that the age of the protolith of the TTG gneisses was ca. 3.4-2.6 Ga, representing a period of paleocontinent formation in the Mesoarchean. Geothermometries indicate the temperature of metamorphism of the TTG gneisses was 522-612℃. Based on these data, the protolith of the TTG gneisses is inferred to have formed during the development of a Mesoarchean paleocontinent that is now widely exposed as a TTG gneiss belt （mostly lower amphibolite facies） in the Maevatanana area, and which records a geological evolution related to the subduction of an ancient oceanic crust and the collision of microcontinent

关键词： TTG gneiss petrology geochronology Maevatanana greenstone belt Madagascar India

Apatite Fission Track Ages in the Duolong Ore District and the Uplift Time of the Qiangtang Terrrane, Tibet

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 408-409页

作者： YANG Huanhuan TANG Juxing SONG Yang LIU Zhibo LIN Bin MLR key laboratory of Metallogeny and mineral resource Assessment Institute of Mineral Resources Chinese Academy of Geological Sciences

Objective Fission track （FT） analysis has developed into one of the most useful techniques throughout the geologic community to reconstruct low-temperature thermal historyof rocks over geological time （Reiners et al., 2005）. The FT method is based on the accumulation of narrow damage trails （i.e., fission tracks） in uranium-rich mineral grains （e.g., apatite, zircon, titanite） and natural glasses, which form as a result of spontaneous nuclear fission decay of 238U in nature. Apatite Fission Track （AFT） has been used in many places in Tibet to study the Qinghai- Tibetan Plateanuplifl-exhumation history. However, few AFT studies have been reported in the Duolong ore district. The Duolong ore district is one of the most important ore districts in the Bangong Co-Nujiang metallogenic belt, Tibet （Lin Bin et al., 2017） and the uplift-exhumation of the Duolong ore district is closely related to the evolution of the Qiangtang Basin. Therefore, AFT of the Duolong ore district will provide important information about the uplift-exhumation history of the Duolong ore district and the Qiangtang Basin.

关键词： Apatite Fission Track Ages the Duolong Ore District the Uplift Time of the Qiangtang Terrrane

基于共价有机框架的分子工程高效光催化CO2还原为CO（英文）

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Science China Materials 2025年第01期 165-172页

作者：赵文玲孙磊杨丽张瑞玲任国庆王森吴昊康欣晨邓伟侨刘乘乘 Institute of Frontier Chemistry School of Chemistry and Chemical Engineering Shandong University Beijing National laboratory for Molecular Sciences Key Laboratory of Colloid and Interface and Thermodynamics Institute of Chemistry Chinese Academy of Sciences College of Chemistry Chemical Engineering and Resource Utilization Northeast Forestry University State key laboratory of Microbial Technology Shandong University

共价有机框架广泛应用于光催化CO2还原中.然而,它们在分离光生载流子方面的效率有限,且催化位点较少,因此其光催化性能有待提高.本文利用分子工程设计了一种芘基共价有机框架（PyTa-H COF）,并将钴单原子（Co SACs）负载在COF骨架中用...

共价有机框架广泛应用于光催化CO2还原中.然而,它们在分离光生载流子方面的效率有限,且催化位点较少,因此其光催化性能有待提高.本文利用分子工程设计了一种芘基共价有机框架（PyTa-H COF）,并将钴单原子（Co SACs）负载在COF骨架中用于二氧化碳还原.在COF中,芘基团可以增强可见光捕获能力和电荷分离能力, Co SACs可以加速光生载流子的迁移及降低决速步的反应能垒.在可见光照射下,PyTa-H@Co在4小时内的CO产率为18.36 mmol g-1h-1,选择性为94%,其性能与目前报道的COFs的最佳性能相当.密度泛函理论计算表明,Co SACs稳定了*COOH中间体,并大大降低了决定性步骤的能垒,从而获得了优异的光催化性能.本工作通过分子工程设计,突出了催化剂结构和功能在提高光催化效率方面的重要作用.

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The Metallogenetic Regularities of Lithium Deposits in China

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 652-670页

作者： LI Jiankang ZOU Tianren LIU Xifang WANG Denghong DING Xin key laboratory of Metallogeny and mineral resource Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences China University of Geosciences

Lithium resources support the development of high-technology industries. China has abundant lithium resources which are mainly distributed in Tibet, Qinghai, Sichuan and Jiangxi. Salt lakes in China have significant lithium reserves, but lithium is mainly produced from hard rock lithium deposits because the extraction from salt lakes requires further improvements. The hard rock lithium deposits mainly occur in granitic pegmatite in the Altay region of Xinjiang and the Jiajika deposit in western Sichuan Province; they mainly formed in the Mesozoic and occurred in a relatively stable stage during orogenic processes. On the basis of the information from 151 lithium deposits or spots, 14 lithium metallogenic series were identified, and granitic pegmatite, granite, and sedimentary types were considered to be the main prediction types of lithium resources. Twelve lithium mineralization belts were divided and a series of maps showing the lithium metallogenetic regularity in China were drawn. We conclude that the hard rock and brine type of lithium resources possibly have a similar lithium source related to magmatism. The mctallogenic features of the lithium in China were related with the distinct history of tectonic-magmatic activity in China. This study benefits the assessment of, and prospecting for, lithium resources in China.

关键词： lithium deposit prediction type of lithium resources metallogenetic regularity metallogenic series pegmatite

Constraints on the Archean atmospheric oxygen and sulfur cycle from mass-independent sulfur records from Anshan-Benxi BIFs, Liaoning Province, China

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Science China Earth Sciences 2007年第10期50卷 1471-1478页

作者： HOU KeJun1,2, LI YanHe1,2? & WAN DeFang1,2 1 key laboratory of Metallogeny and mineral resource Assessment, Institute of mineral resource, Chinese Academy of Geological Sciences (CAGS), Beijing 100037, China 2 key laboratory of Isotope Geology, CAGS, Beijing 100037, China 1. key laboratory of Metallogeny and mineral resource Assessment Institute of Mineral Resource Chinese Academy of Geological Sciences (CAGS) Beijing 100037 China 2. key laboratory of Isotope Geology CAGS Beijing 100037 China

The Archean atmospheric oxygen concentration and sulfur cycle was long debated. The banded iron formation (BIF) is a special type of the sedimentary formation, which has truly recorded the atmospheric and oceanic conditions at that time. In this study, the composition of multiple sulfur isotope (δ 34S/δ 33S/δ 32S) for sulfides bedded in the Archean (~2.7 Ga) BIFs, in Anshan-Benxi area of Liaoning Province has been measured. The value of △33S varies from -0.89‰ to +1.21‰, which shows very obvious mass-independent fractionation (MIF) signatures. These non-zero △33S values indicate that the Archean sulfur cycles are different from what it is today, which have been deeply influenced by gas phase photochemical reactions. Algoma-type BIFs which are closely related to the volcanic activity have negative △33S value, however, Superior-type BIFs which are far away from the volcanic center have positive △33S value. The δ 34S varies in a large range from -22.0‰ to +11.8‰, which indicates that the bacteria reduction activity has already existed at that time, and that the oceanic sulfate concentration has at least reached 1 mmol/L in local areas. Combined with the contemporaneous existence of the hematite, magnetite and the occurrence and preservation of the sulfur MIF, it can be inferred that the Archean atmospheric oxygen level must be at 10-2―10-3 of the present atmospheric level (PAL).

关键词： sulfur mass-independent fractionation, Anshan-Benxi area, BIF, Archean atmospheric oxygen level, Archean sulfur cycle

Monte-Carlo Method for Coalbed Methane resource Assessment in key Coal Mining Areas of China

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Journal of China University of Geosciences 2008年第4期19卷 429-435页

作者：杨永国陈玉华秦勇成秋明 School of resources and Earth Sciences China University of Mining & Technology Department of Earth and Space Science and Engineering York University State key laboratory of Geological Processes and mineral resources China University of Geosciences

Monte-Carlo method is used for estimating coalbed methane （CBM） resources in key coal mining areas of China. Monte-Carlo method is shown to be superior to the traditional volumetric method with constant parameters in the calculation of CBM resources. The focus of the article is to introduce the main algorithm and the realization of functions estimated by Monte-Carlo method, including selection of parameters, determination of distribution function, generation of pseudo-random numbers, and evaluation of the parameters corresponding to pseudo-random numbers. A specified software on the basis of Monte-Carlo method is developed using Visual C＋＋ for the assessment of the CBM resources. A case study shows that calculation results using Monte-Carlo method have smaller error range in comparison with those using volumetric method.

关键词： Monte-Carlo method CBM resource assessment algorithm realization key coal mining areas of China

Timing of Precambrian Basement from East Segment of Tiekelike Tectonic Belt, Southwestern Tarim, China: Constrains from Zircon U-Pb and Hf Isotopic

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Journal of Earth Science 2012年第2期23卷 142-154页

作者：王超刘良何世平李荣社杨文强曹玉亭 Xi'an Institute of Geology and mineral resource State key laboratory of Continental Dynamics Department of GeologyNorthwest University

This study focuses on the determination of the age and provenance of a Precambrian unit on the southwestern margin of the Tarim craton, collectively known as the Ailiankate （埃连卡特） Group and Sailajiazitage （塞拉加兹塔格） Group, which were previously referred to as Paleoprotero-zoic-Mesoproterozoic. Zircon U-Pb LA-ICP-MS dating of chlorite quartz schist and tuff that form the Ailiankate Group and Sailajiazitage Group have yielded age peaks at 780 and 787 Ma, respectively. These data indicate that the Ailiankate and Sailajiazitage groups are Neoproterozoic succession depos-ited at ca. 740-790 Ma. Those strata are temporally equivalent and are likely parts of a single wide spread succession and reflect a rifting process related to the break-up of the Rodinia supercon-tinent. In situ zircon Hf isotopic data from Saila-jiazitage Group show that older zircons （~1 994 Ma） have crustal model ages of 2 272-2 784 Ma, suggesting an ancient crustal growth and re-working. The ~787 Ma zircons have ~2 000 Ma crustal model ages, suggesting derivations from recycled Paleoproterozoic material.

关键词： zircon U-Pb dating Hf isotopic Ailiankate Group Sailajiazitage Group Tieke-like Tarim.