Abstract: Influenced by the complicated geomorphology of the loess tableland area, the approach for evaluating the reservoir of the area is relatively simplistic because the Mesozoic terrestrial formation of Ordos Basin changes rapidly and reservoir types are mainly lithological reservoirs featuring in extra-low permeability and great difficulty to be discovered. In view of the problems of tough surface relief of the area and low conductivity of loess, four solutions are taken to improve the surface-borehole electrical approach, that is, the surface elevations static correction, the static displacement correction, the irregular network routing, and the increment of excitation intensity. The new approach is applied to predict the size of reservoirs and good results are obtained. The prediction range increases to 25~36 km2 from 9 km2. What's more, the prediction result is reliable and has broad prospect for popularization.

Key words: Ordos Basin, loess tableland area, surface-borehole electrical approach, reservoir evaluation, favorable area