The Changling fault is a half graben rift which developed on the Paleozoic metamorphic basement. It is developed quite big thickness deep lacustrine facies black mudstone in Shahezi formation, with high abundance of organic matter, high thermal evolution degree, high hydrocarbon-generating intensity, thus it possess good basis of nature gas accumulation. Faulted period develop two suits of volcanic rocks, which Yingcheng Formation distribute of large areas of burst facies and overflow facies volcanic rocks, the lithology are mainly of acid rhyolites, tuffs and volcanic breccias, with rich cavities and great reservoir physical properties.