Shallow delta reservoir architecture analysis on Putaohua oil formation in Shengping Oilfield

Key words:  Shengping Oilfield  Putaohua oil formation  shallow delta  reservoir architecture  reservoir overlaying model  injection-production relation

Abstract:

Using cores, logging data, analysis data and production data, the reservoir architecture of Pu-Ⅰ oil group in Putaohua Formation in Shengping Oilfield was analyzed in the framework of Miall 's theory. The hierarchy system of multilevel architectural element and the space structure model of shallow delta in the study area were proposed. The results show that three types of interfaces, namely, the mud-muddy siltstone lithological interface, the erosion interface, and the calcareous cementatious sandy interface are developed in single sandstone beds. These interfaces can be used to divide the level-4 architectural element in the vertical direction. According to single channels shapes and their mutual contact relationship, three models of space structures were identified in the shallow delta reservoirs, which are the simple layered stack model, the staggered stack model and the isolated channel model. The advanced connection directions in the single distributary channel, their spatial superimposing relationship, and the relationship between injection wells and production wells affect the distribution of reservoir oil by injectants in sandbodies.