The use of Geosteering to Achieve the Drilling Targets in Multilateral Fishbone Wells in Russkoye Field

Abstract

The purpose of the work performed is to show the possibility of using geosteering not only for achieving geological targets but also for supporting directional drilling operations in multilateral wells.

Drilling of multilateral "fishbone" design well in complex terrigenous section of Pokur suite in Russkoye field is reviewed as an example.

Three kick-off operations with the use of Rotary Steerable System were carried out in an open hole when drilling a horizontal section of the well under review. The well logs of the previous hole were used for optimal selection of the kick-off point.

To control the distance to the reservoir boundaries a 3 layers parameter inversion (based on azimuthal resistivity data) was used in addition to density and porosity sensors.

As a result of the operations performed, the optimal conditions for kicking off with the Rotary Steerable System, were identified within the geological structure of Russkoye field.

Geosteering in real time was successfully used not only for solving geological issues, but for directional drilling as well: optimal kick-off depths were selected for laterals, the trajectory was followed according to the plan; the problems related to bit deflections when the laterals exit the main productive formation were avoided.

The geological targets were delivered as well: the length of the hole in the target formation totaled 98.9%.