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根据西昌盆地首次地震概查资料，获得了较为可靠的地震成果，查明的地腹七里坝、尔乌、炭山、罗木大山等7个局部构造在上三叠统白果湾组顶界，其圈闭总面积达177．5km^2。通过解释，结合七坝1井区域探井成果，对西昌盆地地腹构造的总体分布特征及局部构造进行了较深入的分析、认识，对盆地内主要断裂的位置和展布特征进行了推断及解释。综合地震地质资料解释了古生界二叠系、志留系、奥陶系、寒武系在西昌盆地的基本分布范围，其厚度变化的总趋势是：从西至东、由南往北地层由薄增厚。根据区域地质研究成果，对局部构造进行了含油气条件分析，提出位于米市凹陷内的七里坝和炭山背斜以及罗木大山西支东高点是具有油气远景的构造，为西昌盆地的进一步油气勘探提供了依据。

Structural Features and Oil- Gas Bearing Conditions in Xichang Basin

On the basis of the data on seismic reconnaiss an ce carried out in Xichang Basin first,a relatively reliable seismic result was a chieved and seven buried local structures,such as Qiliba,Erwu,Tanshan and Luomud ashan structures,etc.,were found out,their trap area on the top of Baiguowan For mation,Upper Triassic,the principal target zone,being up to 177.5 km 2 in tota l.Through seismic interpretation and in consideration of the drilling results of the regional exploration well (well Qiba-1),the overall tectonic features and local structures underground in Xichang Basin were investigated in detail and t he position and distribution characteristics of the main faults in the basin wer e reasonably inferred and interpreted.The basic distribution scopes of Permian,S ilurian Ordovician and Cambrian,Paleozoic,in Xichang Basin were determined on th e basis of the seismic geologic data's being comprehensively interpreted.The ge neral trend of the change in formation thickness is that the thickness increases from west to east and from south to north.According to the achievements in regi onal geological resarch and the analysis of the oil gas bearing conditions of local structures,it is put forward in the paper that the Qiliba and Tanshan anti clines and the high of the west branch of Luomudashan anticline in Mishi Sag are the structures being of hydrocarbon potential,thus providing basis for further oil and gas exploration in Xichang Basin.