下扬子区下古生界油气地质条件评价

下扬子区下古生界烃源岩发育,有机质热演化程度高,储盖条件良好,具有形成大型天然气藏的有利地质条件.虽然印支运动对下扬子海盆沉积实体构造改造严重,对油气藏有一定程度的破坏作用,但是由于下志留统高家边组巨厚泥岩的封闭覆盖,下古生界油气藏的保存条件优越,从而在油气勘探领域的评价方面,下古生界明显优于上古生界及海相中生界. 

EVALUATION ON THE GEOLOGIC CONDITIONS OF THE LOWER PALEOZOIC HYDROCARBON IN LOWER YANGTZE AREA

The Lower Paleozoic in Lower Yangtze area which has developed hydrocarbon source rocks,organic matter with high thermal evolutionary degree and good reservoir-cap conditions possesses favorable geologic conditions to form large scale natural gas pools.The Indosinian movement greatly reformed the tectonics of the Lower Yangtze sea basin sedimentary body,and has some degree of katogene on oil and gas pools.But the Lower Paleozoic oil and gas pools have advantageous preservation conditions because of the sealing and covering of very thick mudstone in the Gaojiabian Formation of the Lower Silurian.Therefore,as for the evaluation of hydrocarbon exploration domain,the Lower Paleozoic is obviously superior to the Upper Paleozoic and the marine Paleozoic.