Sedimentary characteristics and hydrocarbon potentials of longitudinal gravity flow deposits in the east subsag of Saihantala Depression

Abstract

Nowadays, Longitudinal gravity flow deposits, as a kind of important deep-water reservoirs, can form a certain scale of lithologic oil and gas reservoirs, which is of fundamental significance in the exploration of oil in Saihantala Depression. The evolution and sedimentary characteristics of the longitudinal gravity flow in the east subsag of Saihantala Depression are analyzed based on the core date, well logging, seismic data, regional geological data, and the method of seismic sedimentology. The sedimentary model of the longitudinal gravity flow and the exploration potential of the lithologic reservoir of longitudinal gravity flow are also discussed. The reservoir is mainly composed of medium-fine sandstone with developed secondary pores. The geological conditions for the formation of axial gravity flow are sufficient provenance, the development of slope breaks and the negative axial topography. The updip direction of the longitudinal gravity in the area has a short extension of the sand body, and the downdip direction has thick massive fine sandstones, which opens up pathways for lithologic reservoir exploration.