苏北盆地热史、埋藏史研究及其对南黄海南部盆地油气勘探的启示

渐新世构造抬升和新近纪地温梯度减小使得盐城组的沉积未对苏北盆地烃源岩起到增温、增熟作用。始新世、古新世地层厚度决定了阜宁组烃源岩的成熟度,戴南组的沉积厚度或残余厚度是影响区内烃源岩成熟度的关键因素;而烃源岩的成熟度控制了凹陷的资源潜力,这是苏北盆地各凹陷油气分布贫富悬殊的主要原因。南黄海南部盆地与苏北盆地属同一构造域,二者在沉积、埋藏、后期改造、成藏期及成藏要素等方面具有一定的相似性,上述认识对该盆地油气勘探具有借鉴意义,南五凹、南四凹是资源潜力相对较好的凹陷。

A study on the geothermal and burial history of Subei basin and its enlightenments on petroleum exploration in South basin,the southern Yellow Sea

Because of tectonic uplifting in Oligocene and geothermal cooling in Neocene,the sedimentation of Yancheng Formation didn't play a role in increasing temperature and maturation of source rocks in Subei basin.The maturity of source rocks in Funing Formation is mainly controlled by the thickness of Eocene and Palaeocene sediments,and the depositional or residual thickness of Dainan Formation is a key factor to affect maturity of source rocks in the basin.As a main reason why various sags are very different in petroleum distribution in Subei basin,the maturity of source rocks has controlled resources potential of these sags.South basin in the southern Yellow Sea is located in the same structural domain as Subei basin,and they are similar to a certain extent in several aspects,such as sedimentation,burial,late modification and hydrocarbon accumulation phases and elements.Therefore,the concept about Subei basin has significant enlightments on petroleum exploration in South basin,the southern Yellow Sea,South 4 sags are considered relatively better in hydrocarbon resources in the basin.