Open File Report 14
Mineralogy and geochemistry of weathered mafic-ultramafic volcanics
from section 4200N at Panglo, Eastern Goldfields, WA
A total of 62 samples, derived from reverse circulation drilling
through weathered volcanic sequences on the western edge of the
Panglo gold deposit, have been analysed chemically and mineralogically.
On the basis of their Cr contents, they have been classified as
either mafic or ultramafic rocks. Higher Cr contents in the oxide
phases, goethite, rutile and spinel, also appear to distinguish
ultramafic from mafic rocks.
More extensive development of alunite and paragonite, which characterise
mineralised and barren shale profiles respectively (Scott, 1989a),
are not present in the weathered volcanic profiles. However, near-surface
Au enrichment (> 0.05 ppm) in the volcanics is associated with
elevated As and sometimes Mo, Sn and W contents. These elements,
plus Cu and Sb, are also associated with sub-economic mineralisation
at depth. Thus, similar pathfinders are present in both shale and
volcanic sequences at Panglo.
Last updated: Tuesday, January 04, 2000 12:31 PMM