关键词: 冀中坳陷, 石炭—二叠系, 沉积体系, 成岩特征, 勘探方向

Abstract: The residual distribution area of Carboniferous-Permian in northwestern Jizhong depression, including Wen'an slope,Yangcun slope and Dacheng uplift, has sufferred from the later strong reconstruction of Indosinian-Yanshan and Himalayan movements as well as differential uplift-subsidence and pullapart-fault depression stages. As a result, the burial history in its east and west denuded belts witnessed uplift-subsidence-uplift and subsidence-uplift stages. However, the depositional systems of Carboniferous-Permian developed well, three types of depositional systems such as tide flat and swamp, delta and river can be identified from the bottom to the top , and the sandstone distributed in the distributary channels or braided channelsmicrofacies of delta and river depositional systems covered large areas ,widely distributed and deposited in a deep depth, and formedmain sand body types in this area. In the process of sandstone buried discontinuously and the reservoir diagenetic, especially, meteoric hypergene leaching process is an important factor to form the secondary porosity in sandstone reservoirs, the porosity degree is generally 15%~25%. Moreover, the deep meteoric leaching along fault surface may keep on improving the reservoir property of the areas developed with many faults, which formed the high quality reservoirs in this area. Based on comprehensive evaluation, it suggests that the west denudation belt should be themost favorable area for gas exploration