Abstract: The Carboniferous in Dinan swell of Junggar basin is a major sequence for petroleum exploration in this area. At present, four bigger gas reservoirs have been found, namely Dixi?10, Dixi?14, Dixi?17 and Dixi?18 gas reservoirs. The latest drilling results show that there are other large?scale gas reservoirs to be found. Based on current vertical lithofacies structural analyses of successful and unsuccessful wells drilling into the Carboniferous, integrated with well logs and seismic data analysis of the lithofacies structural characteristics of well fence profile in gas reservoirs in main well block, it is suggested that the hydrocarbon accumulation control factors are lot, but of which lithofacies is dominant. So the concept of“lithofacies body”should be used to identify the favorable lithofacies in this area. In the upper sequence volcanic rocks, the favorable targets mainly include the andesite and basalt which are scattered in distribution outside the Dixi?17 gas reservoir and slope area of, while in the lower sequence volcanic rocks, the targets could be in scattered volcanic rocks on slope area near the Dixi fault, in andesite, basalt and rubble tuff in the west of Dixi?21 well, and in scattered volcanic rocks along the Dixi fault mainly in the east of Dixi?33 well. The common features of these favorable lithofacies zones are that the volcanic rock mass weathering and leach?ing time was long and distributed near the fault