THE EARLY JURASSIC OIL SHALES IN THE QIANGTANG BASIN, NORTHERN TIBET: BIOMARKERS AND TOARCIAN OCEANIC ANOXIC EVENTS
THE EARLY JURASSIC OIL SHALES IN THE QIANGTANG BASIN, NORTHERN TIBET: BIOMARKERS AND TOARCIAN OCEANIC ANOXIC EVENTS
复制标题
藏北羌塘盆地早侏罗世油页岩：生物标志物与托阿尔期海洋缺氧事件
作者：
YI Haisheng;陈兰等.
藏北羌塘盆地侏罗世特别是早侏罗世双湖—色瓦—安多地区出露了最完整、最广泛的海相沉积地层。富含有机物的海洋沉积物——通常被称为黑色页岩——沉积于早侏罗世，因此多年来许多石油地质学家一直关注它们。尽管近年来地质调查和石油资源评价取得了显著成果，但早托阿尔世（183～176.5 Ma，早侏罗世）海洋缺氧事件导致高有机沉积物沉积的环境条件、机理和过程仍存在争议。本文研究了藏北双湖地区碧洛错剖面下侏罗统油页岩的生物标志物分布。油页岩的特征是短链正构烷烃占显着优势，其最大值为C16或C17，nC17/nC31比率值在9.4至17.8之间，并且Pr/Ph比率较低。此外，所有样品中都存在一系列带有少量伽玛蜡烷的 C27 和 C29-C35 藿烷，如三个样品中伽玛蜡烷/C30-17α-藿烷值为 0.06 至 0.12 以及甾烷 C27/C29 比率高于 1 所示。上述参数表明有机物来源归因于藻类/细菌的贡献。根据成熟度参数，本研究中高藿烷22S/(22S+22R)值均>0.58，甾烷20S/(20S+20R)值均在0.48～0.59之间，与成熟度参数一致。
In the Qiangtang Basin, northern Tibet, the most complete and extensive marine sedimentary strata outcropped in the Shuanghu-Sewa-Amdo area during the Jurassic, especially the Early Jurassic. The organic-rich marine sediments - commonly referred to as black shales - were deposited in the Early Jurassic, therefore, many petroleum geologists have been focusing on them for many years. Although achievements in geological investigations and petroleum resource assessments during recent years have been remark- able, the environmental conditions, mechanics, and process that resulted in the deposition of high-organic sediments during the Early Toarcian (183- 176.5 Ma, Early Jurassic) Oceanic Anoxic Event are still a matter of dis- cussions. In this paper, we deal with the biomarker distributions of Lower Jurassic oil shales in the Biluo Co section, Shuanghu area of northern Tibet. The oil shales are characterized by a marked predominance of short chain n- alkanes with a maxiumun at C16 or C17, nC17/nC31 ratio values between 9.4 and 17.8, and low Pr/Ph ratios. Furthermore, a series of C27 and C29-C35 hopanes with minor amounts of gammacerane are present in all samples, as indicated by gammacerane/C30-17α-hopane values from 0.06 to 0.12 and the steranes C27/C29 ratios higher than 1 in the three samples. The above- mentioned parameters indicate that the organic matter source is attributed to an algal/bacterial contribution. According to maturity parameters, all the homohopane 22S/(22S+22R) values in this study are > 0.58 and the sterane 20S/(20S+20R) values are all between 0.48 and 0.59, which is consistent
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影响因子：
5.3
作者：
Hermoso, Michael;Minoletti, Fabrice;Jenkyns, Hugh C.
通讯作者：
Jenkyns, Hugh C.
影响因子：
1.9
作者：
J. J. Gómez-J.;C. Arias
通讯作者：
J. J. Gómez-J.;C. Arias
影响因子：
64.8
作者：
Summons, RE;Jahnke, LL;Logan, GA
通讯作者：
Logan, GA
DOI：
10.1111/j.1755-6724.2005.tb00904.x
发表时间：
2005-06
期刊：
Acta Geologica Sinica ‐ English Edition
影响因子：
--
作者：
Chen Lan;Yin Haisheng;Hu Rui-zhong;Zhong Hong;Zou Yan-rong
通讯作者：
Chen Lan;Yin Haisheng;Hu Rui-zhong;Zhong Hong;Zou Yan-rong
DOI：
--
发表时间：
2001
期刊：
--
影响因子：
--
作者：
Lin Jin
通讯作者：
Lin Jin