中国南方海相含油气超系统研究

MARINE PETROLEUM SUPERSYSTEMS IN SOUTH CHINA

超越残留构造盆地的含油气超系统,是由共享相似烃源岩、既相互独立又有成因联系的若干个含油气系统构建的含油气成因地质单元,全球具有普遍性。近似的古地理沉积环境和相同时间的区域性烃源岩是确认含油气超系统的前提。中国南方海相独特的构造格局与演变史造就了区域展布的扬子克拉通被动大陆边缘盆地下古生界、扬子克拉通碳酸盐岩台地陆表海盆地上古生界、上扬子前陆盆地上三叠统—中下侏罗统和湘桂地块活动大陆边缘海盆地上古生界、三江古特提斯双弧后边缘海盆地上古生界—侏罗系等 5 个海相含油气超系统,晚燕山期—喜玛拉雅期构造运动差异性使之解体。根据含油气超系统内的已知含油气系统普遍规律,用地质类比法预测具类似源岩的其他低勘探程度盆地(或新区)未知含油气系统的展布特征,这在目前南方海相油气勘探早期阶段有一定指导意义和借鉴作用。

The petroleum supersystem overstepping remnant structural basin is a petroleum genesis geological unit constructed by several petroleum systems which share similar hydrocarbon source rocks, both are mutually independent and have genetic relations. It is of universality on a global scale. The similar palaeogeographical sedimentary environments and the simultaneous regional hydrocarbon source rocks are the prerequisites for affirming the petroleum supersystem. Five marine petroleum supersystems were formed in South China where the marine strata are of unique tectonic frameworks and evolution histories, i. e. the Lower Paleozoic petroleum supersystem in Yangzi craton passive continental margin basin, the Upper Paleozoic petroleum supersystem in Yangzi craton carbonate platform epeiric sea basin, the Upper Triassic - Middle-Lower Jurassic petroleum supersystem in upper Yangzi foreland basin, the Upper Paleozoic petroleum supersystem in Hunan - Guangxi landmass movement continental marginal sea basin and the Upper Paleozoic - Jurassic petroleum supersystem in Sanjiang palaeotethys dualarc back marginal sea basin. The diversity of the tectonic movements during late Yanshan epoch - Himalayan epoch caused these petroleum supersystems to be disintegrated. According to the general laws of the known petroleum systems in the petroleum supersystems, the distribution characteristics of the unknown petroleum systems in the other low exploratory basins (or new regions) with the similar hydrocarbon source rocks can be predicted by geologic analogy method, which is of a certain guide significance and may be used for reference to the early marine oil and gas exploration in South China at present.