The study looked at the sedimentary structures in Baolegentaohai sag north subsags in Erlian Basin. They found that the area has different sedimentary characteristics, with four subprime units. The fault systems in the sag are mainly controlled by large faults on the eastern boundary. The geologic structure in the area shows sedimentary facies belts and formations with multiple origins and coarse sediment. The sand types found include fan deltas, braid river deltas, and nearshore subaqueous fans. The hydrocarbon generation center in the north subsags area is a favorable zone for industrial reservoirs.