Five sedimentary systems, i.e., braided river delta, fan delta, delta, inshore subaqueous fan and saline lake, were distinguished in Member 2 of Hetaoyuan Formation, the Biyang depression.

• 核二段沉积时期，泌阳凹陷发育5种沉积体系类型：辫状河三角洲、扇三角洲、曲流河三角洲、近岸水下扇和盐湖沉积体系。