Mylnikov, Danila (Geosteering Technologies) | Tatur, Olga (Geosteering Technologies) | Sabirov, Airat (Geosteering Technologies) | Brazlauskas, Anton (Geosteering Technologies) | Petrakov, Uriy (Geosteering Technologies) | Sobolev, Alexey (Geosteering Technologies) | Sigarev, Sergei (RN-Uvatneftegaz) | Kustarev, Dmitry (RN-Uvatneftegaz) | Yakovlev, Konstantin (RN-Uvatneftegaz)
The PDF file of this paper is in Russian.
The objective of this work was to drill a horizontal well in the Bazhen formation (Western Siberia, Severo-Demyanskoye field) in order to achieve the maximum possible efficiency both from technological and economical points of view. To solve the task, it was decided to apply a integrated approach to drilling support: synchronously use the methods of geosteering, the results of geomechanical modeling and evaluation of the reservoir properties during the drilling process. The experience of drilling support accumulated by the company at the beginning of the work demonstrated that the coordinated use of the three disciplines leads to an increase in the efficiency of the well construction process.
Pre-drill geomechanical models of the geological interval of interest were constructed for the target well, and also reservoir properties were evaluated. The wellbore stability analysis is carried out and intervals with high risks of destruction of a breed on walls of a chink are revealed. To minimize risks, recommendations were given on the technological parameters of the well construction: mud weight, casing shoe depth, etc.
Based on the actually measured rock properties, the petrophysical characteristics of the formation were evaluated. Geosteering methods were used to correct the trajectory in real time for the most efficient well placement in the target interval with the best reservoir properties. Every time the trajectory was changed, the geomechanical model was rebuilt, demonstrating an updated risk map. As a result, the well trajectory was adjusted taking into account minimization of unstable borehole risks.