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江汉盆地南部荆州—沔阳区地处中扬子区晚印支—中燕山期“南北对冲”的前缘干涉带，前白垩系经受中燕山期挤压冲断构造改造相对较弱, 晚燕山期—早喜马拉雅期构造反转形成江汉断陷盆地。巨厚的白垩系—新近系区域盖层既构筑了盆地南部断陷区晚期沉积重建型整体封存体系，又使区域展布的前白垩系源岩具有晚期深埋生烃和运聚成藏的有利条件,是江汉盆地前白垩系勘探的首选区带。鉴于已发现了前白垩系烃源岩晚期生烃形成古生中储、古生新储型油气藏的重要苗头，建议加强勘探沔阳、江陵、潜江断陷中燕山期构造不整合面及其上下附近的局部构造带，以尽早突破前白垩系烃源的潜在勘探新领域。

OIL AND GAS EXPLORATION PROSPECT OF PRECRETACEOUS IN JIANGHAN BASIN

The Jingzhou—Mianyang region in south Jianghan Basin was located at the front interference zone of the “north south thrust confrontation” in middle Yangzi area during Late Indo Chinese epoch—Middle Yanshan epoch, where the Precretaceous has been weakly transformed by the compressive thrust faulting in Middle Yanshan epoch, and the basin was formed through tectonic reversal in Late Yanshan epoch—Early Himalayan epoch. The thick Cretaceous Upper Tertiary regional caprocks not only constructed the integral rebuilt sealing system of late sedimentary beds in the southern fault depression of the basin but also made the regionally distributive Precretaceous source rocks possessing the favourable conditions of late hydrocabon generating and reservoiring,so that the depression is the first selected area for Precretaceous exploration in the basin.In view of having found out the important symptom of forming the oil and gas reservoirs of the Paleozoic source Mesozoic reservoir and Paleozoic source Cenozoic reservoir rocks through the late hydrocarbon generation of Precretaceous hydrocarbon source rocks, it is suggested in the paper for finding the new potential exploration domain taking the Precretaceous as its hydrocarbon source as early as possible to strengthen the exploration of Middle Yanshan epoch uncomformity surface and its up and down local structural belts in Mianyang, Jiangling and Qianjiang fault depression.