Abstract: Although the remaining resources are still abundant in oil-rich sags such as the Raoyang sag in the Jizhong depression, it is increasingly difficult to discover more sizable reserves in these highly explored sags. To carry out re-exploration and make significant breakthroughs, it is necessary to construct a high-quality 3D seismic data platform over the entire sag. Such a platform would be helpful to investigations of overall structural framework and depositional systems, seismic reservoir prediction and fine delineation of exploration prospects. This paper proposes a new idea of re-exploration that includes optimization of seismic survey plan and acquisition parameters, obstacle avoidance over urban areas, merged processing and target fusion, and then constructs the seismic data platform for the whole Jizhong depression covering an area of 10000 km², which would play a key role for making breakthrough and discovery of more sizable reserves during re-exploration of the oil-rich sags. The proposed idea and practice can also provide references for oil and gas exploration in other similar regions.

Key words: Jiyang depression, oil-rich sag, re-exploration, merged processing, target fusion