关键词: 深部潜山, 油气富集因素, 油气勘探, 廊固凹陷, 霸县凹陷

Abstract: Langgu Sag is a gas enriched depression in the northern part of Jizhong Depression. No substantial progress has been made in the long-term exploration of this area. Currently, the discovered natural gas is mainly concentrated in the middle and shallow layers. To compare the geological conditions for natural gas accumulations in Baxian Sag with those in Langgu Sag, it is assumed that Langgu Sag also has an early lake-forming period with high-quality hydrocarbon source rock existing in Es4-Ek Formation. The desirable reservoirs developed in deep layers, indicating that this sag has the conditions for large-scale natural gas accumulations. The areas with most potential for natural gas exploration should be deep buried hill gas reservoirs and deep natural gas reservoirs surrounding the deep sag. Four orientations for exploration are revealed-shallow-layer structure, deep buried hill, deep conglomerate body and deep compact sandstone. The article elaborates that deep compact oil and gas is the orientation for exploration and study. It also makes a macro assessment of natural gas exploration potential in Langgu Sag.