Geomechanical Support of Well Drilling in the Samotlor Field

Against the background of the continuing decline in total oil production in Western Siberia, the importance of horizontal wells and sidetracks is increasing, especially in the fields that have been developed for a long time. One of these fields is the giant Samotlor field, discovered in 1965 and having a multi-layer structure with locally developed areas of both reduced reservoir pressure (because of long-time development) and increased reservoir pressure (due to the uncompensated effect of water injection). These facts complicate the drilling of wells with large zenith angles, narrow the safe drilling window and ultimately lead to non-productive time. In 2018, Samotlorneftegaz JSC decided to use geomechanical support in the drilling process for complex objects. A full cycle of geomechanical support includes pre-drilling analysis, 1D geomechanical modeling, geomechanical support and post-drilling analysis. The article presents the algorithm of geomechanical support and some results.