Acid Tunneling Technology: Application Potential in Timan-Pechora Carbonates

Abstract

Abstract Petroleum industry needs low-cost and efficient hydrocarbon production enhancement techniques. Oil and gas reserves production need to be economic; therefore high-technology stimulation methods should be used. The considerable part of hydrocarbon world reserves is associated with carbonate reservoirs. To enhance production in carbonate reservoirs, the conventional and special techniques are applied. Sidetracking includes heavy expenses in both money and time, since it requires rig installation and drilling crew gathering. The carbonate natural property of dissolution with acid is used in acidizing and acid fracs. Acid treatment is inefficient in thick reservoirs, thus the treatment design becomes quite complex to achieve efficient acid placement. The acid frac efficiency in carbonate reservoirs is controlled by matrix to fracture porosity ratio, whereas acid fracs in fractured reservoir with zero matrix porosity will be unefficient. This paper describes the possibility to apply a relatively new enhancement technique – acid-tunneling – in Timan- Pechora oil province carbonate reservoirs in Russia. In this paper the evaluation methods of vertical and multilateral well potential are specified; the productivity ratios of various multilateral well designs in dual porosity reservoirs vs. permeability anisotropy are shown; the pseudoradial skin- factor calculation procedures of multilateral well are described. The well candidate technologic and economic selection criteria are also considered. As a result, the matrix of production enhancement technology application in Timan-Pechora oil and gas province has been developed.