Abstract:
Based on section measurement, field investigation and physical property data of the carbonate reservoirs in Dengying Formation on the western side of the Xuefeng Mountain, this paper deals in detail with the rock types,space types, quality, and distribution characteristics of the reservoirs and the relationship between the depositional environment and the reservoir quality. There exist two principal types of reservoirs in the Dengying Formation: the oolitic beach sediments and the dolomite. Solution cavities, intercrystal pores and fractures with good connectivity constitute the main reservoir space. The reservoirs of tidal flat facies and platform edge facies north of Baojing-Cili fault seem to be the most favorable carbonate exploration zone. Oolitic dolostone and dolorudite of the first member of Dengying Formation around Zigui area constitute the best reservoirs in the study area, with maximal porosity 11.00%, (8.27% on average) and maximal permeability 7.72×10-3μm2(3.66×10-3μm2 on average). Dengying Formation dolostone constitutes important reservoirs widely distributed on the western side of the Xuefeng Mountains, which were deeply buried in the middle Yangtze region with good cap and preservation conditions. Further research on Dengying Formation reservoirs will be of great significance for gas exploration in southern China.