Open File Report 47
The distribution of gold and other elements in soils at Mulline,
Lintern, M.J. and Butt, C.R.M.
Soils, lateritic gravels, calcretes and saprolites were sampled
at the Peach Tree and Lady Gladys gold prospects in the Mulline
area, 50 km west of Menzies. Each of these sites has moderate reserves
of gold as laterite-hosted deposits that are characterised by ferruginous
gravels invaded by pedogenic carbonate.
Strong associations were found between gold and iron, and gold
and the alkaline earth metals. In particular, gold distribution
appears to be positively correlated with calcium and magnesium in
the top 0.5 m of the soil profile and with iron in various zones
beneath this. The alkaline earth metals are present as calcite and
dolomite and iron as goethite or hematite. The association with
Fe oxides is probably related to the formation of the deep lateritic
regolith during the Tertiary, whereas the association with the pedogenic
carbonates is of more recent origin, related to weathering under
recently imposed semi-arid climates. The study has demonstrated
the importance of selecting the correct soil horizon when sampling
for gold and support similar data from elsewhere in the Yilgarn
Block, Western Australia.
Last updated: Thursday, January 06, 2000 08:43 AM