Abstract: In view of the characteristics of rapid lithofacies change and great difference in oil-bearing property of the glutenite mass in Anfutun steep bank of Damintun Sag, comprehensive geological research method was used for paleogeomorphic restoration, sedimentary facies analysis and microscopic study of reservoir characteristics. It was found in the study that thick layered fan delta glutenite was widely developed in the western fault trough belt, with the characteristics of skirt belt multi-stage overlapping distribution. The subfacies sandstone reservoir in the Anfutun fan front was developed with intergranular dissolved pores, presenting sound reservoir properties and hydrocarbon occurrence; the sand mass was in direct contact with the mudstone of the depression, which was condcutive to preferential capture of oil and gas near the source, and it was clear that the subfacies at the fan delta front was the dominant lithofacies. The glutenite mass at the Anfutun steep bank was characterized by "reservoir control with facies zone and reservoir control with physical properties". This research is of guiding significance for hydrocarbon exploration of other glutenite masses in the western fault trough.

Key words: steep bank, glutenite body, fan delta, reservoir characteristics, ancient landform, Damintun Sag