油气盖层研究现状与认识进展

Current status and progress in research of hydrocarbon cap rocks

综述了油气盖层研究历史和国内外研究现状,分别总结了泥岩盖层及蒸发岩类盖层认识进展,分析了封盖机理研究现状。提出油气盖层研究经历了5个阶段,逐渐由早期侧重于盖层物性研究发展到变形过程及成藏过程中的盖层有效性研究,包括优质盖层研究、盖层力学性质研究以及盖层封盖性与成藏条件匹配关系研究等。蒸发岩类是世界各地重要的油气盖层,后期岩溶改造会对其封盖性能产生一定的影响;泥岩的沉积结构、构造、成分组成,特别是粘土含量对泥岩盖层封闭性能影响较大;深埋地下的高演化泥岩仍具有优质的封盖性能。尽管发现毛管物理封闭、超压封闭和毛管多相封闭等多种封闭类型,但是,毛管物理封闭作用是最基本的封闭机制。总体上,国际上目前研究盖层较多的国家主要有美国、挪威、澳大利亚、英国、意大利、德国等,研究单位包括高校、政府机构和油气公司等。

It was reviewed in this paper the history and current status of the research of hydrocarbon cap rocks.The research progress in both mud and evaporite cap rocks was summarized,and the current research status of dynamic sealing mechanism was analyzed.There are 5 stages in the research development of cap rocks,and the focus of research has shifted from rock physics to deformation process and sealing effectiveness during hydrocarbon accumulation,such as study in high quality seals,mechanical properties of cap rocks,matching between sealing capacity and accumulation conditions,and so on.Extensive literature review suggests that evaporites are very important hydrocarbon seals all over the world and karstification in later stages would affect the sealing capacity;sedimentary texture,structure,and composition（especially clay content） of the mud rocks show fairly important influencees on sealing capacity of mud rock seals;deeply buried mud rocks which have been through high diagenetic evolution still show excellent sealing capacity.Capillary physical sealing,overpressure sealing,capillary multiphase sealing and several other types of sealing mechanism have been discovered and studied,but the capillary physical sealing is the most fundamental sealing mechanism.Counties that are active in cap rock research include the United States of America,Norway,Austrialia,Britain,Italy,Germany,and so on.Institutions involved are mainly colleges and universities,goverment institutions,and petroleum companies.