As part of uranium exploration being carried out over the oldest basement rocks forming inliers to the Adelaide Geosyncline within the southern Mount Lofty Ranges, an airborne scintiilometer survey was flown across the Houghton Inlier during December 1968 along north-south lines spaced 1000 feet apart, with a sensor mean flight elevation of 400 feet. Isoradioactivity maps were prepared by the survey contractor for Bi214 (U), Tl208 (Th), K40, Bi214/Tl208, Bi214/K40 and Tl208/K40. Noranda's interpretation of these maps delineated 23 low order anomalies that are apparently emanating from Archaean basement outcrop, but all were downgraded by Unimin's follow-up ground inspections and scintillometric traverses. The corresponding anomalies recorded on the ground were relatively small in extent, with a few isolated and localised high readings in the range of 170 to 700 counts per second obtained from metasomatic mineral segregations in poorly expressed lodes within the bedrock.