Biogeochemical expression of uranium mineralisation and geology, by Eucalyptus camaldulensis in the Paralana Creek drainage system, South Australia

This item is only available electronically.Mineral exploration in Australia today faces a great challenge: to efficiently detect mineralisation buried beneath extensive regolith cover. Because their roots penetrate the regolith cover, establishing the elemental signatures of certain plants (biogeochemical exploration) can aid in the detection of buried ore deposits. At the highly prospective Mount Painter Inlier, Eucalyptus camaldulensis (river red gum) was sampled in the ranges and extending out onto the plains bordering Lake Frome. Here it is shown that the leaves from Eucalyptus trees can detect a range of elements including important pathfinder elements related to U mineralisation. A significant finding of this study is that the sediments thought to be associated with the geochemical transport and host of U mineralisation, like those that host the Four Mile U deposit, have relatively elevated U2/Th values. The geological setting of these locally elevated U results also appears to be equivalent to the Four Mile mineralisation, based on available field exposures. Therefore, this area could well represent a biogeochemical expression of mineralisation equivalent to the soon to be mined Four Mile U deposit. This study demonstrated that Eucalyptus biogeochemistry has significant advantages over other approaches in that it is cost and time efficient, culturally unobtrusive, and can identify relationships between plant biogeochemistry and the underlying geological substrate, in particular, U-mineralisation. The examination of more Eucalyptus camaldulensis (and more widespread species in the area) from surrounding areas therefore also warrants further investigation.Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 200