中国海域及邻区主要含油气盆地与成藏地质条件

PRIMARY HYDROCARBON BEARING BASINS AND THE POOL FORMING CONDITIONS IN CHINA SEAS AND ADJACENT REGIONS

中国海域及邻区分布有近５０个沉积盆地，其中大部分发育在大陆边缘，而主要含油气盆地则分布在大陆架部位。盆地的起源、发生、发展受控于大地构造不同时期的构造运动，形成诸如裂谷型断陷盆地、走滑盆地以及非典型前陆盆地等多类型沉积盆地。从区域广度阐述了盆地沉积的有利相带对油气成藏的重要性，尤其是陆架盆地的成藏地质条件所形成的富集油气藏，包括已发现的一大批大中型油气田，更具有最佳的开发前景。

There are about fifty sedimentary basins in China seas and adjacent regions,most of them develop in the continental margin,but primary hydrocarbon bearing basins are distributed in the continental shelf.Tectonic movements in different phases controlled the origin and development of the basins.Particularly,various types of sedimentary basins were forming because of the influence of continental margin activity.Most of Cenozoic sedimentary basins have good pool forming conditions of large medium oil and gas fields and have good prospects.There are a series of predominantly Neogene filled large sedimentary basins in China seas,the underlying is pre Mesozoic basement,and there are favourable hydrocarbon generation and pool forming facies,such as lacustrine,swamp,shallow marine and bathyal facies.In most Neogene sedimentary basins thickness of strata is more than 10000m,with very adequate material base for hydrocarbon and pool generation.When continental margin moves frequently and intensly,multi phases swamp deposits occur in basins and lacustrine alternates with swamp,which makes generated multi source hydrocarbon migrate to traps to forming pools.Parcicularly,coal bearing series of lacustrine facies are major gas prone source rocks.For example,Xihu depression of the East China Sea Shelf Basin and Qiongdongnan Basin are the main gas areas of China seas.