In a search for possible economic base metal mineralisation in the Willouran Ranges, a review and statistical trend surface analysis of previous company sream sediment geochemical data, combined with MIM's own orientation studies on the distribution of metal content within these sediments, then followed by closer-spaced semi-regional stream sediment sampling (998 samples taken @ ~20 samples per square mile), have indicated that low order (to 5 times background) copper anomalies occur over parts of the lower Callanna Beds and over certain of the diapiric structures. The best such anomalies, occurring within the Willouran Diapir between Dome Hill and Willouran Hill, were resampled (67 samples) to define a linear anomaly measuring about 1.5 miles long by 0.5 mile wide, containing sparsely mineralised quartz veins developed at the faulted contact of the diapir with country rocks. This anomaly is regarded as the northwards extension of the copper stream sediment anomalism previously found by Anaconda in a similar geological environment on the Dunn's mine prospect and the Rook mine prospect. Check soil sampling (504 samples taken over a 100 foot by 400 foot grid) performed over these high order stream sediment sampling sites has shown that the elevated copper content of the coarse stream sediment fraction is a legitimate feature that does not stem from contamination of surface detritus by mine spoil. The soil samples taken from near basic igneous intrusions outcropping 4 to 5 miles north-west of Mirra Bore did not indicate any associated anomalous copper. 125 of the higher order stream sediment samples were also resampled by MIM for molybdenum, but no values of significance were obtained.