凯里地区油源对比及油气成藏史分析

基于前人研究资料和野外露头剖面详细观测及油苗样品实测数据，运用碳同位素、饱和烃色谱和甾萜烷生物标志等技术，对凯里地区油苗进行了地球化学特征研究和油源分析，探讨了凯里地区油气成藏史。研究认为：虎47 井原油、洛棉上青山下奥陶统红花园组油苗、凯棠翁二段油砂、沥青砂的源岩为上震旦统和下寒武统；炉山大风洞二叠系油苗主体为自生自储，并渗混有上震旦统—下寒武统烃源岩生成烃的信息。加里东晚期构造运动使烃类大量排出，而且形成适时的圈闭捕获油气成藏。尽管后期沉积盖层的叠加，下寒武统烃源岩在三叠世末达到高成熟—过成熟阶段，至燕山期构造隆升前，红花园储层经历的最高温度仍小于175 ℃（Ro<1.3%），油相对得以保存。晚燕山期以来的逆冲推覆作用导致深、浅构造不协调，部分二叠系烃源岩再次深埋，与下古生界混源。

Analysis of Oil and Source Rock Correlation and Pooling History in Kaili Area

This paper analyzes geochemistry and oil source and thermal histories in Kali area are discussed by using carbon isotope, saturated hydrocarbon chromatography, steranes and terpanes based on the results of previous researches, the observation of field outcrop and the measuring of oil seepage samples. The results indicate that NO. 47 oil well at Huzhuang and oil seepage hosted in the Ordivican O1h member at Shangqingshan area, as well as the hydrocarbon source rock of asphalt sandstone and oil sand are of the same oil source, mainly originating from upper simian series and lower Cambrian. Oil seepage hosted in the Permian source rocks of DaFengdong area is mainly self-generation and self-storage, and may be the mixture of oils generated from the upper simian series and lower Cambrian source rocks. Hydrocarbon was expulsed by Tectonic movement of late Caledonian and trap formed at suitable time. Although the later period deposits the cap rock superimposition, the source rock of lower Cambrian was not achieving the high mature-overmature stage in the end of Triassic. Before the Yanshanian structure uplifted, maximum temperature of Honghuayuan reservoir was still lower than 175 ℃（Ro<1.3%）, and the oil phase to maintain. Deep and shallow structure were uncoordinated and the partial hydrocarbon source rock was re-buried deep again by the thrust-nappe function from the Yanshanian structure.