Please choose your delivery country and your customer group
An airborne magnetic and radiometric survey of the Laverton and Edjudina 1:250,000 map areas was flown in 1966 to assist the systematic regional geological mapping of the Western Australia Precambrian Shield, and the search for metals. The magnetic pattern is attributed to differences in magnetic properties between rock units at or near ground level. Geological strikes and the boundaries of major rock units were interpreted by delineating magnetic trends, by subdividing the area into zones of specified magnetic character, and by assessing the geological significance of these zones by reference to mapped geology. The area comprises heterogeneous acidic igneous masses, with ill-defined more basic regions, which enclose elongated outcrops of interbedded lava and sediment sequences. Areas where geological and magnetic evidence conflict are discussed in some detail. Sixteen fold axes, one cross-fold axis, twelve major dikes (one remanently magnetized), and fourteen faults were delineated. Ultrabasic intrusions could not be resolved with absolute certainty from the magnetic pattern. The radiometric data reveal many high anomalies which are mainly correlated with granite outcrops. Eighty-three radiometric anomalies satisfying the point-source criteria were detected and, of these, fifty-one are recommended for ground investigation. (Author)