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.