海外M盆地烃源岩与油气勘探

海外M盆地主要发育三叠系和二叠系两套烃源岩，但认识不清，影响了勘探方向的选择。本文通过对该盆地烃源岩常规指标和有机地区化学特征进行综合分析，认识如下：该盆地烃源岩类型以腐泥一腐殖为主的Ⅱ2和Ⅲ型，有机碳为多低于0．3％，其R0多大于1．5，处于成熟一过成熟，产油潜率相对较低，三叠系烃源岩产油潜率小于0．05mg／g，二叠系产油潜率多小于0．5mg／g，表明该区烃源岩以生气为主，生油能力较低，且容易发生裂解。因此该盆地的油气勘探应以浅层天然气勘探为主。

Research on Source Rock and Hydrocarbon Exploration of Oversea M Basin

The overseas M Basin mainly developes two sets of source rocks named triassic and permian. It, however, can not be understood clearly so that the exploration direction was affected. The article mainly comprehensively ana- lyzes the regular Indices of source rocks and chemical properties of the organic area of the basin. The result shows that the source rocks are II2 and III types with sapropelic and humic type dominated, TOC is almost below 0. 3 % , Ro is above 1.5 for the most part, they are in the stage of mature and overmature with relatively lower potential oil productivity, that of triassic source rock is below O. 05 mg/g, permian source rock below 0. 5 mg/g. It indicates that the researched area predominantly produces gas with the lower capacity for oil producing, and oil is likely to crack. The basin should be given priority to shallow exploration on gas.