This report summarises the relevant results of previous copper exploration in the Yudnamutana Hill area by Utah Exploration Co. and Australian Aquitaine Petroleum Pty Ltd, and suggests an ongoing exploration programme for stratiform copper. It also describes the stratigraphy and palaeogeography of the Adelaidean Callanna Beds, and the detailed geology of areas mapped by the previous companies prior to 1980. Their work focussed on and thoroughly tested the Lower Callanna Beds, and while stratiform mineralisation up to grades of 13.5% Cu was intersected, no economic mineralisation was encountered. The present report is more concerned with the Upper Callanna Beds where much less work has been carried out and where potential still exists. It is recommended that Marathon explore for stratiform copper in these formations, and also conduct mapping and sampling to assess the stratiform copper potential of the Burra Group.