Shallow, open pit mineable near-surface coal within Permian sediments along the eastern rim of the Boorthanna Trough was the target of exploration in EL 108 and in adjoining EL 104 to the south. After conducting photo-interpretation on aerial photographs of the area and studying Bouguer gravity maps to compile a geological structural model for this part of the trough, Shell undertook reconnaissance open hole rotary percussion drilling during March-April 1974 of 6 holes totalling 1142 m. One drillhole was unable to penetrate below the base of the Jurassic sandstones, and only the southernmost hole in the licence area, SDA 10, intersected the Early Permian coal measures. A 60 m thickness of the objective Mount Toondina Formation was encountered in this hole, containing several thin interbeds of sub-bituminous coal and coally shale, none of which are >1 m thick. The coal itself is middle-ranking in quality, and appears dull and unweathered, despite the uppermost seam occurring within only 4 m of the Permian - Jurassic unconformity. In addition to finding this older coal, a 0.5 m thick shaly coal seam was intersected within Lower Cretaceous sands in hole SDA 13, but had almost disappeared through lensing out into shale in hole SDA 14, drilled less than 300 m distant to the east. The drillholes were all petrophysically logged with neutron, gamma ray, density and caliper probe tools at 1:120 scale, and the four principal coal seams that had been found were also log profiled in detail at 1:24 scale. Because they lie below 100 m depth, which is too deep to allow surface mining, and also by their nature indicate only poor potential for making better nearby coal discoveries, Shell decided to cease doing work on this licence.