The application of analysis technology of modern volumetric attributes to the exploration of weathering crust reservoir:A case study of M531 Sub-members of Ordovician Majiagou Formation in TAO7 Block, the Sulige Gas field

The weathered crust reservoir of Ordovician Majiagou Formation in the Sulige gas field of Ordos Basin is characterized by thin thickness,strong inhomogeneity and complex gas?water relation,and the reservoir development is aeffected by multiple controlling factors such as deposition,digenesis and structure,which causes the difficulty of the exploration.Taking the M531 Sub?members of TAO7 block as an example,the authors specially studied the weathering crust reservoir by the application of analysis technology of modern vol?umetric attributes. Combined with the development characteristics and the geophysical response characteristics of crust reservoir, the study included improving the SNR of original seismic data with structure?oriented filter and comprehensively predicting the micro faults using volumetric curvature and ant tracking on the basis of filtered data.The karst grooves were described by strata slice and volumetric fusion.The prediction result shows that the analytical technology of modern volumetric attributes could elaborately describe the karst res?ervoir by using the routine seismic data more sufficiently and reduce the prediction multiplicity.Several techniques and methods have a high goodness of fit as proved by drill wells and provide a good basis for the further petroleum exploration in the study area.