Abstract:

The internal architecture of sand body controls fluid flow, which influences development effect. Sand body development model of braided river channel ofHe 8 member in Suxi X well block was studied according to the existing reservoir sand body architecture research methods and based on short-term cycle comparison in a single stratigraphic framework. Sand body architecture types are classified into truncation style channels, complete channels and relatively isolated channels. The sand body morphology mainly manifests box shape and Christmas tree shape in the rising half cycle, and manifests finger shape mostly in the descending half cycle. In the cross section, the sand bodies which have overlapping phenomenon vertically and intertwined characteristics horizontally are obviously developed. Sand body of the same channel laterallymigrated to the west. The sand body distribution is characterized by a big ratio of width and thickness, small curvature and discontinued （effective reservoir sand bodies）. Four kinds of sand body development models of He 8 member in the study area were summarized as followings: strong migration of overlaying channel sand body, river intersection channel sand body, relative isolation channel sand body and weak overlaying channel sand body.

Key words: abnormal high pressure and low permeability gas reservoirs, stress sensitivity, start-up pressure gradient, flow differential equation, numerical simulation