Formation model of multi-stage fracture reservoirs inside the buried hills in Liaohe Depression

It has been accepted that reservoirs can be formed in the weathering crust at the top of buried hills.But whether they can be formed in the deep side of buried hills remains unknown.This paper focuses on the buried hill in the Xinglongtai area of west sag in Liaohe Depression.The development of the multi-stage fracture reservoir is discussed from such aspects as buried hill lithology,tectonic movement,and hydrocarbon generation system and transport mode.A formation model of multi-stage fracture reservoirs is established.Under the guide of it,Well Xinggu 7 was drilled and a large reservoir about 1000 meters high in the deep side of buried hill was found.It paves the way for the exploration into the deep side of buried hills in Liaohe Depression and around the country.