The Lower Brent Group Stratigraphy, Reservoir Architecture and Reservoirs Qualities in The Deep Northern Viking Graben

Abstract

This thesis will give a detailed description of the stratigraphy, reservoir architecture and reservoir qualities of the Lower Brent Group (Oseberg, Rannoch, Etive and Lower Ness formations) in the deep northern Viking Graben. Core descriptions and well logs from Valemon –Kvitebjørn, Huldra and Oseberg field are used to characterize 19 faceis, 10 facies association, 6 depositional systems, and 2 sequences of the Lower Brent Group in order to assess the factors that control their distribution within the Rungne sub-basin. The Brent delta is interpreted to be of mixed tide and wave influence, because of the abundance of double and single mud draps and tidal bundles in the Rannoch Formation and estuarine deposits in the Etive Formation. Transition form an exposed wave dominated shoreline into an embayed tide dominated shoreline is documented. The Oseberg formation is interpreted to be a part of the main Brent system, based on the lateral interfingering of the Rannoch Formation, indicating that the Oseberg delta was still active in the Oseberg field during deposition of Rannoch formation. Due to thickness change in the Lower Brent group and facies change; from wave influenced shoreline to wave and tide dominated shoreline in the Rannoch formation fault activity is identified.