The limited hydrothermal karst and mixed zone beneath the anticline axis controls the porosity distribution of ordovician system and it is anticipated that surroundings of the axis of fold formed by compressional reverse orverthrusting during indo - chinese epoch and the coordinated area of morphology of anticline in the screen of buried hill and that of top surface morphology is the best position for development of the reservoir 局限的热液岩溶和裸露的背斜轴部之下的混合带对千米桥潜山奥陶系孔隙分布具有重要控制作用,预期在印支期挤压逆冲作用形成的背斜轴部,特别是潜山内幕背斜形态与潜山顶面形态相互协调的区域,应是储层发育最好的部位。