Abstract: The Aogula Fault Zone in the Songliao Basin exhibits complex kinematic characteristics, making the study of the spatiotemporal matching relationships of various reservoir-forming controlling factors challenging, which brings challenges to the accurate characterization of reservoir morphology. To address this issue, a comprehensive analysis of geological, seismic interpretation, and drilling data was conducted to understand the structural development history and fault causes. Based on the understanding of reservoir formation, the mechanisms of fault-controlled oil and gas accumulation were clarified. The fault-dense zone in the study area can be divided into two levels, and the faults are classified into three types based on their relationship with stratigraphic position. The study reveals that the Aogula Fault Zone is composed of two antithetic "S"-shaped main faults, experiencing three stages: faulting, sagging, and inversion. During the faulting stage, the activity intensity and elongation percentage of the fault zone are the highest, gradually weakening during the sagging stage, accompanied by multiple reverse regulating faults, and strengthening again during the inversion stage. Oil-source faults serve as vertical migration pathways connecting source rocks and traps, controlling the formation of fault-related traps and providing favorable conditions for oil and gas migration and accumulation. The research results can provide theoretical support for further exploration targeting and reserve enhancement.

Key words: Songliao Basin, Aogula Fault Zone, structural evolution, fault-controlled oil and gas