| The complex distribution of gas and water is a difficult problem in the exploration of natural gas in Dongfang 13 gas field, Yinggehai Basin. Based on the analysis of the lithology and logging interpretation data of 7 wells and the comparison of 2 cross-well sections, combined with the interpretation of the cross-well seismic section and the study of the geological characteristics of the gas field, the gas-water spatial distribution law and model in Dongfang 13 gas field are revealed. It is shown that the gas reservoirs are mainly distributed in the channel of submarine fan, with gas reservoir structure of the low part developing water and the high part developing gas edge water. From the Dongfang 13-2 structure to the east of the Dongfang 13-1 structure, the gas reservoir scale gradually becomes smaller and more dispersed. The formation water can be divided into three types: united edge water, local deep channel bottom water and inner layer water caused by tight sandstone. The bottom water and inner layer water are common in the middle of the edge water gas reservoir of the Dongfang 13-2 structure and the Dongfang 13-1 structure, which complicates the gas water distribution of the gas reservoir. Based on the gas-water distribution and the scale of gas reservoir, it is inferred that Dongfang 13 gas field is composed of Dongfang 13-2 edge water integrated large-scale gas reservoir, Dongfang 13-1 edge water medium-scale gas reservoir and Dongfang 13-1 edge dispersed small-scale gas reservoir. Gas and water are regularly distributed according to the three gas reservoir models. |
