Implementation the Multilateral Wells With ICDs for Development of Formations With High Viscosity Oil and Underlying Water Zone

Abstract

Vertical wells drilling for development of viscous oil in formations with low oil saturated thickness and underlying water zone, usually has a poor economics due to fast water breakthrough (water coning). The wells with 300 - 400m horizontal sections with a dense placing are able to achieve high recovery factor, but have a limitations during drilling and completion and subsequent production management. The paper discusses the results of pilot works on the multilateral well construction in a highly viscous oil field with underlying water. The well designed especially for development producing intervals of bobrikovsky formation, widespread in a Volga-Ural region of Russia. Based on detailed 3D geological model of the reservoir a well with three laterals was designed, equipped with inflow control devices (ICD) with sliding sleeves to enable isolation of each wellbore. The well has high horizontal sweep efficiency with a possibility to fully manage the inflow from every lateral in case of water breakthrough. Using while drilling the deep azimuthal resistivity measurement tool allowed placing the wellbores in the top of pay zone far from water contact. According to the LWD measurements, the proper ICDs parameters were determined before well completion in order to equalize the inflow profile of the horizontal section. A significant increase in productivity and cumulative oil production of multilaterals allow to reduce wells density and ensure economic efficiency, even despite the increase in costs compared to horizontal well.