The first member of Kongdian Formation in South Kongdian of Huanghua Depression was studied to understand its origin. The researchers used various methods like clastic composition analysis and seismic profiles to analyze the parent rock characteristics. They found that sediment sources in the region come from the north, east, south, and west, with the north being the most significant. The sands in the area mainly come from continental blocks and volcanic arcs, indicating the basin is a rift basin with multiple sediment sources in the Cenozoic era.