This report outlines the methods used and the results obtained in this investigation. The significance of the results and other data is discussed. The writer was appointed Senior Geologist, Geochemistry Section in September 1969. The basis of the appointment was: the conduct of regional geochemical surveys and the investigation in detail of particular ore deposits, with attention to the stratigraphic distribution of metals. The functions of the Geochemical Section have developed along two lines: (1) Building up of data on metal distributions and concentrations in the rocks of South Australia, (2) interpretation of the data in geological terms from the genetic point of view. Both of these functions have ultimately important practical applications in the search for concealed mineralisation. The results available to date of the combined geological and geochemical investigations of the Cambrian and Marinoan rocks show very clearly that intelligent interpretation and application of them can only be done by considering the geological and geochemical environments at the time of deposition of the sediments as well as their subsequent geological history. To date in Australia there has been a marked tendency to regard ore formation as a rather late episode in the history of the host rocks. As an example of the influence of environment, the Pb values in the Nairne Pyrite member show a close relationship to zones of thickening of the underlying Inman Arkose (see fig, 3 in Report G.S. 1552 "The Adelaide Geo syncline - and the Kanmantoo Trough"). Cambrian and Marinoan palaeography, as well as tectonics, structure and metamorphism appears to have been a factor in metal concentration and cannot be neglected. This is a consequence of accepting an initial syngenetic origin for the mineralization. This report is therefore in 3 parts. (1) Activities of Geochemical Section (2) Syngenesis in ore deposition as related to the Cambrian geology of South Australia. (3) Ore Environments in the Cambrian and Marinoan of South Australia. (This part of the report discusses the significance of this approach in ore search in S.A.)