3D Seismic Interpretation Of The Moorari/Woolkina Field: Stratigraphic And Structural Analyses Of The Basal Jurassic, Toolachee And Epsilon Intervals; Cooper Basin, South Australia.
Honours Degree, 1998
University of South Australia
The Moorari/Woolkina area is located in the Patchawarra Trough of the southern Cooper Basin PEL's 5 and 6, South Australia. A 64 square kilometre 3D seismic survey was acquired over the area in 1994, covering much of the existing grid of mixed vintage 2D data.
A detailed investigation of seismic anomalies within the Patchawarra Formation resulted in the drilling of Cardam #1, off structure to the east of the Moorari/Woolkina Field. This well, targeting stratigraphically trapped hydrocarbons, discovered gas in several mid-Patchawarra sands.
The aim of this project was to evaluate similar anomalies that may be present within the `basal Jurassic', Toolachee and Epsilon intervals, investigating stratigraphic and structural opportunities, and the depositional environments. The attribute analysis of these intervals required the generation of amplitude, dip, azimuth, isopach maps and seismic facies classifications using various software packages.
A study of the structural history (mid-Permian to lower Jurassic), and the correlation of seismic data to well data, was important in identifying the depositional environment and the distribution of sediments throughout the study area. It is interpreted that the `basal Jurassic' interval was deposited as a river-dominated delta, with distributary mouth bar deposits on the northern and eastern flanks of the Moorari structure. The Toolachee and Epsilon Formations are thickest on the flanks of the structure, with the most prospective region for hydrocarbon accumulation being to the north.