A number of oil recoveries have been made, and oil shows recorded, around the margins of the Patchawarra Trough. The bulk of this oil is generally believed to be derived from the Cooper Basin, with transmission to the Eromanga section where the intervening Nappamerri Formation and impermeable Triassic sequences are either thin, sandy or faulted. However, if Eromanga source potential can be proven, Eromanga traps could be prospective even where these sealing units are thick, mud-dominated or unfaulted. Investigations were restricted to the Poolowanna and Birkhead Formations of the Trough area because the remaining units appear to be immature (Murta Member and Toolebuc Formation) or lacking in organic carbon (Hutton and Namur Sandstones). Organic petrology and pyrolysis analyses of mudstone and coal samples from the Poolowanna and Birkhead suggest that both formations contain oil-prone kerogen, and that this material is widely distributed within these strata throughout the Trough. The study has revealed that Poolowanna source potential is only moderate because the area of thickest source rock development does not coincide with the area of greatest maturity. Birkhead Formation potential is poor also because the formation is only marginally mature and the source facies is poorly developed in the axis of the Trough. Consequently it is expected that only relatively small volumes of oil would have been expelled by both formations, so prospects without obvious access to additional Cooper Basin source rocks now constitute high-risk exploration targets.