The depositional model of the second member of Hetaoyuan formation in Wuyang depression

Based on seismology,drilling and provenance quantita-tive tracing,we presented an extremely asymmetric sand-body distribution of the second member of Hetaoyuan forma-tion in Wuyang depression.Aiming at this special distribu-tion model of sand body,we integrated the regional geolog-ical setting and the development discipline of salt rock,and established the deposition model of the second member of Hetaoyuan formation in Wuyang depression as follows.In The northern boundary fault acted intensively during the deposition of the second member of Hetaoyuan formation,The relevant raising of northern provenance resulted in the barrier of northern source and therefore breaking the balance between southern and northern source during the deposition of the third member.The sandbody scale of braided riverdelta in the south was large and slope advanced relatively far,but the sandbody scale of fan delta near the northern was small and distributed locally along the boundary fault.