Structural evolution of the Sora/North Sora Sub-Basins, South Sea, Korea

The structural interpretation of the Sora and North Sora sub-basins are conducted using up-to ca. 75 cross-sections to determine major structures. The purpose of this study is to better understand the structural development of the Sora and North Sora Sub-Basins. Seismic lines conducted at 1990, 1997, 2006 supported by KNOC (Korea National Oil Cooperation) and well data are re-interpreted in terms of fault geometries and key horizons considering basin-type and tectonic evolution. The results show that both Sora and North Sora Sub-Basins experience similar geological evolution since Cenozoic. However, the NE-trending regional structures beneath the Late Cretaceous unconformity are different as results of faulted depression controlled by Yandang movement. Trap geometries are formed before end of the late Mid-Miocene contractional deformation. Reactivated rift-related structures are preserved in North Sora Basin. However, syn-rift growth pattern is not observed within the Sora Basin, indicating that it might be a depression at the end of Cretaceous. These results will provide better understanding on the geometric and kinematic basin evolution history, which might help to develop new potential petroleum play concept that can apply to the site survey for Carbon Capture and Sequestration (CCS) storage.