大巴山前缘震旦系及下古生界含油气条件探讨

A Discussion on Oil and Gas Bearing Conditions of Sinian and Lower Paleozoic on Dabashan Mountain Frontal Border

大巴山前缘为上扬子准地台北缘的一个台缘拗陷。晚震旦世至志留纪为浅海台地型沉积,有多套良好的生储盖组合。晚震旦世至中三叠世具继承性台缘古隆起,现今构造具“推覆构造”特征。在推覆体之下有明显的重力正异常,可能存在多类型的隐伏圈闭,是勘探油气的有利目标。

Dabashan Mountain frontal border is a platform depression on the north verge of Upper Yangzi Platform. It is a shallow sea step terrian deposit from Late Sinian to Silurian and there are several sets of good source-reservoir-caprock association. It is succussion platform paleo-uplift from Late Sinian to Middle Triassic and nowaday structure has the characteristic of 'nappe structure'. There is an obvious gravity positive abnormality under the nappe and it is possible that there are various types of hidden trap,which is the favourable target for oil and gas exploration.