A STRATIGRAPHIC ANALYSIS OF THE TALGEBERRY OILFIELD

Abstract

ATP 299P(2) is located in the south-west Queensland portion of the Jurassic Cretaceous Eromanga Basin. Exploration drilling within the permit has resulted in the discovery of several oil pools which are stratigraphically controlled. Appraisal drilling at the Talgeberry Oilfield demonstrated this point when Talgeberry-2, drilled at a structurally higher location, failed to encounter either of the producing sands in Talgeberry-1. Oil is currently being produced from the Wyandra Sandstone and Birkhead Formation in Talgeberry-1 and from the Murta Member in Talgeberry-2.

Depositional models are presented for each of the producing reservoirs at the Talgeberry Field, based upon dipmeter interpretation. An integrated seismic stratigraphic study was also undertaken on the Birkhead Formation reservoir.

Oil production at Talgeberry is currently confined to distributary channel sands or near-shore distributary mouth bar sands. Distal facies of the distributary mouth bar have been intersected and, while containing oil, have been found to be generally tight.

Dipmeter interpretation has proven valuable in determining depositional environment but is limited in defining the a real extent of the reservoir. Seismic-stratigraphic studies are able to define the reservoir geometry better and lead to a more comprehensive understanding of the depositonal environment.