未熟-低熟油中金刚烷烃类化合物的成因及其潜在意义研究

项目名称： 未熟-低熟油中金刚烷烃类化合物的成因及其潜在意义研究

项目编号： No.41272169

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 包建平

作者单位： 长江大学

项目金额： 85万元

中文摘要： 现阶段国内外对金刚烷类化合物的研究主要集中在确定高、过成熟烃源岩中有机质的成熟度和原油在高演化阶段遭受热裂解程度的判识上，一般认为这类化合物的分布与组成特征及浓度变化均与高演化作用密切相关，因而把它作为高、过成熟作用的标志。但是，在我们的研究中发现在有机质成熟度偏低的烃源岩和未、低成熟油中用全扫描就能容易地检测出金刚烷类化合物，而且其相对组成如甲基金刚烷指数（MAI）和甲基双金刚烷指数（MDI）却明显偏高。依据现有的观点这显然与其所处的演化阶段或所经历的热成熟作用是不相符的，这一现象揭示出地质样品中的金刚烷类化合物形成于有机质热演化的早期阶段，而且其相对组成特征也不一定完全受控于热成熟作用。因此，开展低演化烃源岩和未、低成熟油中金刚烷类化合物的分布、组成与浓度变化的研究对揭示这类特殊化合物的分布规律、形成的地质-地球化学条件和认识其地球化学应用的边界条件不但具有理论意义，同时具有实用价值。

中文关键词： 烷基单金刚烷系列；烷基双金刚烷系列；成熟度；烃源岩；原油

英文摘要： In the present literatures for diamondoid hydrocarbons study in petroleum geochemistry field at home and abroad, much more attention have been paid to determining the thermal maturity of organic matter in high or over-mature source rocks and the extent of oil cracking in the reserviors. Generally speaking, based on the known results in literatures, there is a close relationship between the distribution, the relative composition and the concentration variation of diamondoid hydrocarbons and the highly thermal maturation in the source rocks and crude oils. Therfore, they have usually been used as the indicators for highly thermal evolution of organic matter. However, it has been found that diamondoid hydrocarbons are very common in the immature to lower source rocks and the crude oils with immaturity and lower maturity in Subei Basin and Qaidam Basin, and could be identified easily even by full scan of GS-MS analysis. In addition, their relative compositions such as methyl adamantane index(MAI) and methyl diamantane index(MDI) in those geological samples are obviously higher compared to their thermal maturity and could not be explained by the present known viewpoints. This phenomenon may imply that the generation of diamondoid hydrocarbons in geological samples occurred during the early stage of thermal evolution

英文关键词： alkyl adamantane series；alkyl diamantane series；maturity；source rocks；crude oils