Report comprises a brief review of the hydrocarbon potential of an unexplored region within PELs 5 and 6, approximating 20,000 square miles in area, where Permian sediments are thought to exist. The area is situated north of Lake Eyre, between the shallow basement area of the Birdsville Track Ridge and the Pedirka Sub-basin which underlies the western portion of the Total 66 farmout block. Present interpretation of the existing geological and geophysical data in the area postulates that Permian sediments are limited to the Pedirka Sub- basin: Permian sequences were encounted in the four FPC(A) wells, Mount Crispe 1, Witcherrie 1, Purni 1 and Mokari 1 drilled during 1963-66. This study presents a re-interpretation of the same data to the effect that Permian sediments are much more widespread and, in fact, form another basin possibly akin to the Cooper Basin, where commercial oil and gas discoveries have recently been made. The new interpretation suggests that the Permian sediments of the Pedirka Sub-basin form only the northwestern marginal area of a much larger Permian basin, the Lake Eyre Permian Basin.