New Approach to Offshore Field Development in Russia: Ultra Deep LWD Measurements for Accurate 3D Reservoir Model Update

Abstract

In this paper we describe a new approach to the development of oil and gas fields in Russia and CIS countries, which consists of integrated use of well log data while drilling and deep directional electromagnetic measurements (EM) for geosteering applications with subsequent update of the geological static model. This approach was implemented in 2016 on the offshore Filanovsky field to reduce drilling risks in the first production wells, and to refine and update the 3D static model. At the initial stage of drilling estimated structural uncertainty in the field was ± 15 m (vertical depth). The use of deep directional resistivity technology (DDR) while drilling allowed to determine bed boundaries remotely based on resistivities at vertical distance of up to 24 m (vertical depth). Based on inversion of deep electromagnetic measurements (inversion), the first wells were successfully drilled with all the geological and technical tasks completed. The obtained well log data together with inversion allowed refining of the correlation of the target beds with seismic data, and updating the velocity-depth model as well as structural surfaces of the deposit. New surfaces, together with the petrophysical interpretation of the data from the horizontal and production intervals obtained during drilling, were used to update the stochastic 3D model for subsequent reserves estimation and planning of future wells.