关键词: 鄂尔多斯, 奥陶系, 马六组, 白云岩, 成因

Abstract: Peleozoic gas exploration and development have achieved great progress in Ordos Basin.The Paleozoic explorations of deep formations in eastern area and western Tarim Basin are still in the ascendant.Reservoirs in these oil fields have less or more relationship with carbonates,which play a very important role in domestic and potential abroad(Middle East and Central Asian,etc) exploration and development markets. Therefore diagenesis research of carbonate reservoir has a great significance.Based on the field observations of seven field outcrop sections and six exploration wells,we integrally studied the genesis of dolomite and the influence factors for the reservoir properties by using various experimental methods on thousands of samples. Dolomite is one of the most important rock types in Ordovician Carbonates of Majagou Group in Ordos Basin.It is indicated that dolomites are multi-factor and multi-period genesis.The diagenesis periods and different array of sequence experienced in the formation of dolomite play overwhelming roles in reservoir properties.

Key words: Ordos Basin, Ordovician, Formation Maliu, Dolomite, genesis