Earth Sciences Seminar: Dr Diana Plavsa

Presenter

Dr Diana Plavsa
Future Industries Institute - UniSA

My current research is largely on development of geochemical vectors associated with mineralizing systems from mineralogical perspective.

Specifically, I am interested in characterizing the chemistry of accessory phases (e.g. rutile, monazite, zircon etc.) that are associated with mineralization and whether anomalous geochemical signatures representing mineralizing fluids can be detected and subsequently preserved in the overlying cover.

My aim is to develop novel ways of detecting footprints of large mineralising systems in the cover to aid exploration in areas of thick cover.

Rutile as an exploration and provenance tool

Rutile (TiO2) is a chemically and physically robust accessory phase mineral that occurs largely in metamorphic rocks (greenschist to granulite grade), as well as igneous, sedimentary and mantle rocks. In addition, rutile is a major host of HFSE elements (e.g. Nb, Ta, Zr, Hf) as well as a range of other metals including Sb, W, Sn, Fe, Cr, Zr, Hf, Mo and V. Consequently, it has been used extensively in thermochronological (e.g. metamorphic conditions) and geochemical studies involving mantle evolution and provenance studies.

In addition, enrichment of elements such as W, V, Fe, Sn, Sb and Mo in rutile have been detected in rutile grains associated Au deposits (e.g. Kalgoorlie deposit in WA). Consequently, rutile carries great potential as a vectoring tool towards large mineralising systems. Here we present rutile chemistry from a range of 'background' and 'mineralized' rocks in order to detect and characterize anomalous signatures associated with Au mineralisation.

Our findings suggest origins of rutile must be thoroughly examined and rutile polymorphs (anatase and brookite) characterized in order to use rutile as a vectoring tool. We also discuss the use and limitations of common rutile provenance discriminators (Nb and Cr contents of rutile) and propose a new and more robust way of using rutile in provenance studies.

Tagged in Physical Sciences, Earth Science, For current students, Research seminar