EXISTENCE AND SIGNIFICANCE OF MICROUMBONES IN KARST BASIN: SAMPLE FROM ORDOVICIAN KARSTIC PALEOGEOMORPHY IN ORDOS BASIN
岩溶盆地中微隆起带的存在及意义――以鄂尔多斯盆地奥陶纪岩溶古地貌为例

Karstie geomorphies are consisted of karstic upland, slope and depression. Karst basins are considered mixed water area, in which pore spaces are sorely filled and reservoir properties are unsavoury. With ingoing exploration, good reservoir beds which are located in microumbones are found in some of karst depressions. Combined with thickness map of benxi formation of Carboniferous and distributed relation map of basement rift and magmatite, chronic activity of basement Carboniferous to the formation of microumbones. Under action of percolation and underflow, mieroumbones are composite water but not gathering water and weathered crust developes at sure depth. Early pore space growth provide conditions for reservoir beds reconversion, so microumbones in karst depression have good potention to exploration.