Geochemical insights into contribution of petroleum hydrocarbons to the formation of hydrates in the Taixinan Basin, the South China Sea
Geochemical insights into contribution of petroleum hydrocarbons to the formation of hydrates in the Taixinan Basin, the South China Sea
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南海台西南盆地石油烃对水合物形成贡献的地球化学见解
DOI：
10.1016/j.gsf.2020.03.006
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发表时间：
2020-03
影响因子：
8.9
通讯作者：
Jiang-Hai Wang
中科院分区：
文献类型：
--
作者：
Yan Li;Yun-Xin Fang;Qian-Zhi Zhou;Xiang-Po Xu;Jin-Zhong Liu;Guo-Yi Zhou;Jiang-Hai Wang
根据δ~(13)C和δ_D值，南海中国海甲烷水合物被广泛认为是生物成因的。尽管前人做了很大的努力，但热成因油气的贡献仍然被低估了。本研究通过对台西南盆地不含水合物和含水合物沉积物的生物标志物和孔隙水地球化学参数的测定，通过对有机质来源输入、环境条件和微生物活动的对比研究，评价了石油烃对水合物矿床形成的贡献。结果表明，与不含水合物的沉积物相比，含水合物沉积物中硫酸盐还原菌产生的C14-C16分支饱和脂肪酸(δ13C)含量较高，与溶解无机碳(DIC)的正SFA13C值、甲烷浓度升高、碱度降低以及离子(Cl−、Br−、SO42−、Ca~(2+)、Mg~(2+))的浓度波动相一致。这些数据表明，含水合物沉积物中的微生物活动相对活跃，环境条件也发生了相应的变化。BSFA(−34.0‰至−21.2‰)、正构烷烃(−34.5‰至−29.3‰)和甲烷(−70.7‰至−69.9‰)的碳同位素组成共同表明，SRB可能在不同类型的有机碳而不是甲烷上茁壮成长。结合南海众多油气藏和油气运移通道，未分解复杂混合物(UCm)、奇偶优势(OEP)值(约1.0)和生物标志物模式的出现表明，深层油气藏中的石油烃是最有可能的碳源。我们的新结果提供了重要证据，表明深部油气藏可能对南海甲烷水合物矿床的形成有贡献。
Methane hydrate in the South China Sea (SCS) has extensively been considered to be biogenic on the basis of itsδ13C andδD values. Although previous efforts have greatly been made, the contribution of thermogenic oil/gas has still been underestimated. In this study, biomarkers and porewater geochemical parameters in hydrate-free and hydrate-bearing sediments in the Taixinan Basin, the SCS have been measured for evaluating the contribution of petroleum hydrocarbons to the formation of hydrate deposits via a comparative study of their source inputs of organic matters, environmental conditions, and microbial activities. The results reveal the occurrence of C14–C16branched saturated fatty acids (bSFAs) with relatively high concentrations from sulfate-reducing bacteria (SRBs) in hydrate-bearing sediments in comparison with hydrate-free sediments, which is in accord with the positiveδ13C values of dissolved inorganic carbon (DIC), increasing methane concentrations, decreasing alkalinity, and concentration fluctuation of ions (Cl−, Br−, SO42−, Ca2+, and Mg2+). These data indicate the relatively active microbial activities in hydrate-bearing sediments and coincident variations of environmental conditions. Carbon isotope compositions of bSFAs (−34.0‰ to −21.2‰),n-alkanes (−34.5‰ to −29.3‰), and methane (−70.7‰ to −69.9‰) jointly demonstrate that SRBs might thrive on a different type of organic carbon rather than methane. Combining with numerous gas/oil reservoirs and hydrocarbon migration channels in the SCS, the occurrence of unresolved complex mixtures (UCMs), odd-even predominance (OEP) values (about 1.0), and biomarker patterns suggest that petroleum hydrocarbons from deep oil/gas reservoirs are the most probable carbon source. Our new results provide significant evidence that the deep oil/gas reservoirs may make a contribution to the formation of methane hydrate deposits in the SCS.
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影响因子：
5.3
作者：
W. Ussler;C. Paull
通讯作者：
W. Ussler;C. Paull
DOI：
10.3969/j.issn.0001-5733.2009.07.019
发表时间：
2009-07
期刊：
--
影响因子：
--
作者：
Wu Shiguo;Dong Dongdong;Yang Sheng-xiong;Zhang Guang‐xue;Wang Zhi-jun;Li Qing-ping;Liang Jinqiang;Gong Yue-hua;Sun Yun-bao
通讯作者：
Wu Shiguo;Dong Dongdong;Yang Sheng-xiong;Zhang Guang‐xue;Wang Zhi-jun;Li Qing-ping;Liang Jinqiang;Gong Yue-hua;Sun Yun-bao
DOI：
10.1016/j.palaeo.2005.04.030
发表时间：
2005-10
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
T. Pape;M. Blumenberg;R. Seifert;V. Egorov;S. Gulin;W. Michaelis
通讯作者：
T. Pape;M. Blumenberg;R. Seifert;V. Egorov;S. Gulin;W. Michaelis
脂质生物标志物模式反映了墨西哥湾（阿特沃特谷和格林峡谷）以贻贝和管虫为主的渗透碳酸盐的不同形成环境
影响因子：
3.9
作者：
HongXiang Guan;Dong Feng;Daniel Birgel;Jörn Peckmann;Harry H.Roberts;Nengyou Wu;Duofu Chen
通讯作者：
Duofu Chen
南海北部神狐海域沉积物孔隙水中溶解无机碳(DIC)及其碳同位素组成
影响因子：
2.3
作者：
Yang, Jing-Hong;Wu, Neng-You;Liu, Jian;Yang, Tao;Jiang, Shao-Yong;Chen, Dao-Hua;Lu, Ge
通讯作者：
Lu, Ge