Controlling Factor and Distribution of Paleo-karst Development in Ordovician of Southern Ordos Basin
鄂尔多斯盆地南部奥陶系古岩溶发育控制因素及展布

The Ordovician carbonate suffers from multi-stage and multi-type paleo\|karst in south of Ordos basin. The development of paleo-karst is controlled by ancient tectonic setting, lithologic association characteristics, and especially ancient geology and landform. On the basis of field mapping method, impression method, residual thickness method, and according to the result of seismic facies trace and seismic interpretation, the paper depicts ancient geology and ancient landform in detail in south of Ordos basin. From south to north, ancient landform is divided into karst highland, karst platform and eroded slope. The eroded slope is furthermore divided into the erosion shallow grooves, erosion pits, karst hills and karst beams. Due to the different paleo\|karst background and paleohydrologic conditions, the distribution of favorable areas is obviously different.