Reports on a study aimed at improving the delineation and correlation of pre - Patchawarra Formation sediments in the greater Daralingie and Wooloo Trough area, since a clearer understanding of this stratigraphic section is needed in order to pursue low side fault and stratigraphic flank plays in this area. Current mapping of this section within the Daralingie Field by the Santos Development and Exploration Groups utilises data from different computer databases constructed according to differing well sampling criteria, resulting in delineation inconsistencies and stratigraphic interpretations unreliable for application on a regional scale. In order to integrate available data and achieve more consistent formation top picks, 58 wells were analysed throughout the study area. 3 key wells were identified on the basis of section penetration, representative wireline log character and cuttings/core lithological descriptions, to provide guidelines for mapping the Merrimelia Formation and Dullingari Group in the other wells. The study had 2 significant outcomes: Merrimelia Formation is interpreted to be present in more wells than previously tabled, giving it a wider regional distribution;pre-Permian formation tops are accordingly deeper where such Merrimelia intersections are interpreted. Seismic mapping of the respective pre - Patchawarra horizons away from well control is thought to be of questionable value.