鄂尔多斯盆地奥陶系马家沟组沉积时期,由于受中央古隆起及边缘坳陷的制约,处于陆缘盆地环境,储层的溶蚀作用较弱,充填作用较强,空间展布具有强烈的非均质性。这种发育特征宏观上受沉积环境、古沟槽、古水动力条件的制约,微观上受孔隙类型、充填强度以及充填物类型的影响。沉积环境决定了沉积岩的类型,后者是储层发育的物质基础;古沟槽纵横交错,控制着残余溶丘的平面分布;压释水决定着区域充填程度的差异。孔洞充填物质的类型主要包括白云石和方解石,白云石对有效孔隙的保存具有建设性作用,方解石对有效孔隙的保存具有破坏性作用,白云石、方解石混合充填区与古沟槽交切形成的微岩溶地貌相叠合,是今后盆地东部奥陶系勘探的主要方向。

During the sedimentary of Majiagou formation, the wide area of the eastern Ordos basin were controlled by  the middle palaeohigh and the marginal deep, lied in the surrounding of the continental margin basin .The solution roles are faint very much, the filled roles  are intension very much, the strong heterogeneity are exhibited on the space distribution. The characteristics of development are controlled by sedimentary  surrounding, palaeogroove and palaeohydrodynamic condition on the macrocosmic, controlled by the pore styles and the filled intension and the filled styles on  the microcosmic. Sedimentary rocks are decided by the sedimentary surrounding, which is the substantial base of the reservoir development; the plane distribution  of the residual solution platform are controlled by palaeogroove; the difference of the filled intension are controlled by the compacted released water. The  filled styles of pore and core include mainly dolomite and calcite. the dolomite react on construction, the calcite react on destroy roles. The filled region of   the dolomite and the calcite mixed and the physiognomy  of mini-karst are piled up, the region is the main domain of the Ordovician explored in the future.