Mineral magnetic evidence for heterogeneous sandplain regolith in Western Australia

The origin of sandplains in Western Australia remains a contentious issue. Resolution of the debate is hindered by a lack of detailed sedimentological evidence. The application of mineral magnetic analyses to this problem shows that the sands demonstrate both inter- and intra-profile variability. Fifteen sandplain profiles show clear differences in their mineral magnetic properties. Some correlations are also found between the mineral magnetic data and the abundance of primary heavy minerals, dithionite extractable iron and the amount of clay in the sediments. The results suggest that mineral magnetic analysis can offer useful insights into the composition of sand terrains. While the magnetic data are consistent with other lines of evidence that suggest an in-situ origin of the sandplain sediments, further analysis is needed before a firm conclusion can be reached on the origin of these sediments on the basis of magnetic data alone. (C) 2000 Academic Press.