3D seismic identification technique for Ordovician erosion flutes in the eastern Ordos Basin

The carbonate weathering crust is a major gas reservoir of the Lower Paleozoic period in the eastern Ordos Basin. The petroleum exploration results proved that the reservoir properties were strictly controlled by palaeokarst, especially by the configuration of erosion flutes. The identification accuracy of the erosion flutes is relatively low using the conventional thickness methods. A new method for recognizing the erosion landform characteristics is proposed on the basis of the 3D seismic geomorphology. The application of the new method in Fuxian area of the eastern Ordos Basin provides the high-precision palaeokarsts distribution for the exploratory well planning. The combination of the 3D seismic geomorphology with the seismic attribute images is valuable for the identification of the Ordovician erosion flutes and can reduce drilling risks. The 3D seismic identification method is proposed for recognizing the erosion flutes.