The Search for Stratigraphic Traps in the Southern Patchawarra Trough, South Australia

Abstract

A seismic stratigraphic study of the Early Permian Patchawarra Formation has been undertaken to delineate zones of reservoir sandstone development and to identify stratigraphic hydrocarbon traps in the western Patchawarra Trough region. In this intracratonic basinal setting, the Patchawarra Formation is dominated by paludal and lacustrine sediments with fluvial sandstones. The Patchawarra Formation in the Patchawarra Trough is a prolific, liquids-rich gas producer with discovered-in-place resources approaching 28 x 109 cubic metres (1 TCF).With minimal well control in the study area, seismically defined increments of strata (SIS units) have been mapped areally away from nearby fields. The occurrence of sand-prone facies has been predicted through the development of a palaeogeographic model for each unit.Integration of facies and structural maps has led to the identification of a suite of intraformational and basin edge stratigraphic plays.

The Geology of Fluvial Deposits

“…Examples include at least some of the Permian fluvial reservoirs of Cooper Basin, Australia (Stuart et al 1988;Stanmore and Johnstone 1988). Examples include at least some of the Permian fluvial reservoirs of Cooper Basin, Australia (Stuart et al 1988;Stanmore and Johnstone 1988).…”

“…This technique has formed a key to the location of most of the Tuscaloosa fields in Mississippi (e.g., Hersch 1987;Garrison and Chancellor 1991) and is becoming of increasing importance in the Gippsland, Surat, Cooper, and other Australian basins, which are beginning to enter the mature exploration phase (e.g., Clark and Thomas 1988;Stanmore and Johnstone 1988;Elliott 1989). This technique has formed a key to the location of most of the Tuscaloosa fields in Mississippi (e.g., Hersch 1987;Garrison and Chancellor 1991) and is becoming of increasing importance in the Gippsland, Surat, Cooper, and other Australian basins, which are beginning to enter the mature exploration phase (e.g., Clark and Thomas 1988;Stanmore and Johnstone 1988;Elliott 1989).…”

Burial/exhumation histories for the Cooper–Eromanga Basins and implications for hydrocarbon exploration, Eastern Australia

“…At the end of Early Permian/beginning of Late Permian times, a compressional phase resulted in rejuvenation of older basement structures and produced, for example, the northeast‐orientated GMI trend (Apak et al ., 1993). Although the tectonic activity along pre‐Permian fault trends (Stuart, 1976; Stanmore & Johnstone, 1988) caused uplift and erosion of previously deposited sediments, sediment accumulation was continuous in deeper parts of the basin (Battersby, 1976; Stuart, 1976). Vitrinite reflectance modelling showed that there is no offset in the amounts of exhumation determined from the Lower Permian units (Patchawarra Formation, Murteree Shale and Roseneath Shale) and those determined from Upper Permian and Triassic units (Toolachee Formation and Nappamerri Group) (Mavromatidis, 1997).…”