The Dongwu Movement caused the exposure of Maokou limestone on the earth's surface and made it experience the su-pergene weathering process. Drilling reveals that the gas reservoir is closely related to the location and intensity of ancient landforms. Palaeogeomorphology is the main factor that affects the development and distribution of ancient karst. Southeastern Sichuan basin has had less drilling and is unevenly distributed, with insufficient exploration. Combining drilling with seismic survey, the authors exqui-sitely restored ancient karst landform of Maokou by applying the impression method and the residual method. A comparison of these two methods show that both methods can recover the same basic trend palaeogeomorphology. According to the geological features and practical data of the study area, the authors hold that the impression method has higher reliability. Based on an analysis of the an-cient water system, the authors divided the study area into karst highland, karst slope and karst basin by combining it with paleogeo-logic map and drilling. The NW-SE trending karst highland in the southwest of the study area has the same highland as the karst highland in Shunan area, but it is higher than Shunan area. The groundwater runoff and corrosion holes of the karst slope area make it a favorable area for karst exploration.%东吴运动造成茅口组灰岩暴露地表并经历了表生风化作用。钻井揭示，气藏储层段与古岩溶所处的位置及强度密切相关，古地貌是控制古岩溶发育与分布的主要因素。针对钻井较少且分布不均、勘探程度不高的川东南地区，将钻井与地震紧密结合，分别运用残余厚度法与印模法对茅口组岩溶古地貌进行恢复，结果对比发现，这2种方法恢复出来的古地貌趋势基本一致。结合研究区的地质特征和实际资料，认为印模法可信度更高。在古水系特征分析的基础上，结合古地质图和钻井资料，把研究区划分为岩溶高地、岩溶斜坡和岩溶盆地，其中岩溶斜坡又可分为岩溶陡坡与岩溶缓坡。研究区西南岩溶高地与蜀南岩溶高地为同一岩溶高地，呈北西-南东向展布，且相对蜀南地区隆起幅度更高。在岩溶斜坡区，地下水以径流为主，溶蚀孔洞发育，是岩溶勘探开发的有利地区。
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