墨西哥湾盆地油气分布规律及成藏主控因素分析

Petroleum distribution rules and controlling factor analysis of Gulf of Mexico Basin

墨西哥湾盆地属裂谷与被动大陆边缘叠加的复合型盆地,盆地经历了3个演化阶段。在研究墨西哥湾盆地形成演化的基础上,分析油气分布规律。油气藏主要发育于被动陆缘期,盆地内共有5套成藏组合,常规油气与非常规油气并存,其中常规油气主要有3个成藏组合,具有由陆向海依次为侏罗—白垩系成藏组合、古近系成藏组合、新近系成藏组合;其成藏主控因素为进积、盐和砂体。非常规油气目前发现2套成藏组合:Eagle ford和Haynesvil-bossier页岩油气带,均位于陆上;成藏主控因素主要为有机质丰度和热演化程度。

The Gulf of Mexico Basin is a composite basin with passive continental margins superimposing on rift basin. The basin has experienced 3 evolution stages. Based on the research of basin formation and evolution, the distribution rules of oil and gas were analyzed. Oil and gas mainly developed during the passive margin period. There are 5 sets of oil and gas plays including the conventional and unconventional petroleum. The 3 main con-ventional oil and gas plays are located following seaward direction, which include the Jurassic-Cretaceous play, the Paleogene play and the Neogene play, from onshore to offshore. The main controlling factors are prograda-tion, salt and sand distribution. The 2 unconventional oil and gas plays include the Eagle ford and the Haynesvill-bossier shale belt, both locating onshore. The main controlling factors are organic matter abundance and thermal evolution.