Integrated Study of the Upper Jurassic Sognefjord Formation across the Troll West Field, North Sea

Abstract

The growing global demand for hydrocarbons and reduction their reserves in producing fields have made the accurate characterization of reservoir properties (e.g. porosity, permeability and water saturation) away from well control an important research area for oil and gas industry. The integrated reservoir characterization studies may significantly improve the economics of the exploration and field development projects by reducing the number of required wells, which have to be drilled for successful exploration and production of oil and gas reserves, and also provide opportunities for a more efficient recovery of hydrocarbons from the existing fields. Seismic inversion is a well known and widely used processing procedure for predicting the distribution of reservoir properties. One of a relatively new approach to inversion is a nonlinear multitrace genetic inversion. The basis of genetic inversion is the neutral network algorithm combined with the genetic procedure in order to generate a nonlinear multitrace operator, which transforms the seismic data into the property described by training well log data. The objectives of this study are a detailed seismic interpretation, petrophysical evaluation and reservoir characterization of the Sognefjord Formation across the Troll West Field. The seismic interpretation allowed to reconstruct the structural and stratigraphic framework of the northern Horda Platform and better understand the tectonic evolution, stratigraphy and depositional environments of the area. Log-derived values of porosity and water saturation along with interpreted horizons served as a basis for reservoir characterization study. The capabilities of the genetic inversion to predict porosity and water saturation values away from well control were tested and demonstrated on the Sognefjord Formation across the Troll West Field. The results of this integrated study (e.g. distribution of porosity) provide opportunities for more accurate hydrocarbon reserves estimation and improving the recovery of oil and gas through further optimization of development and production strategies in the Troll West Field.