Boundary fault linkage and its effect on Upper Jurassic to Lower Cretaceous sedimentation in the Gudian half-graben, Songliao Basin, northeastern China

The Songliao Basin, northeastern China, is one of the few ultra-large petroleum basins in the world. Fault superposition, linkage, and stratigraphic architecture have produced a complicated basin evolutionary history. In this study, we report the boundary fault linkage and associated Upper Jurassic and Lower Cretaceous stratigraphic record using 3D seismic reflection data and well data. Our results show that the geometry of the boundary Gudian fault was originally controlled by six shorter fault segments, which grew and were linked during a syn-rift stage, then frictionally weakened and inverted in a post-rift stage. This boundary fault has variably controlled coeval syn-rift sedimentation. Fault segments in the middle section controlled the development of the limited, but thickest, Huoshiling and the first member of Shahezi Formations in the early syn-rift stage (ca. 150-133.9 Ma). Later, that control gradually weakened and vanished on succeeding the second member of Shahezi and Yingcheng Formations in the late syn-rift stage (ca. 133.9-105 Ma). The processes and the diverse syn-rift sedimentation response to Gudian fault growth and linkage have further implications for graben evolution and can guide hydrocarbon exploration in the Songliao Basin. This study will help elucidate the different controls of boundary fault linkage on associated sedimentation, as well as rift basins development in eastern China and similar areas throughout the world.