Sidetracking Implementation on Western Siberia Oil Fields with Jurassic Reservoirs

Abstract

Nowadays sidetracking is an effective technology that allows increasing of residual oil production as well as recovering damaged wells. During 2006 - 2007 JSC Tomskneft drilled 69 sidetracks mainly in Jurassic reservoirs. Average oil flow rate after sidetracking reached 29 tons per day, average water cut equals 49 percent. Liability of modeling is 97 percent for liquid flow rate and 76 percent for oil flow rate. There are several geological and technological reasons for lower actual production rates. This report summarizes methodical issues of sidetracking decision making process. The relevance of sidetracking The majority of Tomskneft oil fields are low permeable Jurassic fields at the last stage of development. Reservoir geological heterogeneity is the essential reason for non-uniform oil field depletion. Some oil fields are characterized with rapidoil flow rate decline at critical water cut following unprofitable oil production (Figure 1).