Research
I am conducting research that combines economic geology, metamorphic and igneous petrology, and structural geology to study metallogenic processes. I am investigating a range of mid- to deep-crustal processes that influence metal distribution and mobility including:
- sulfide melt immiscibility in magmatic mixing zones at the base of arcs (MASH zones) and its role in ore genesis;
- the P-T-t-D window(s) for metamorphic generation of sulfur-rich hydrothermal fluids; [link to new research page,
- the behaviour of metals during silicate anatexis; and
- sulfide partial melting during metamorphism.
An important aim is to link the results of these studies with tectonic models for the genesis of felsic-intermediate magma-related Cu-Au deposits (relates to 1 and 3) and orogenic gold deposits (relates to 2).
Research Projects
Metallogeny of the lower crust
Dr A. Tomkins
Funding for 2006: $128,264 (Monash Fellowship scheme)
With increasing depth in the Earth’s crust, temperature and pressure rise and rocks become progressively more metamorphosed. Most mineral resources from near the Earth’s surface, however in many cases, metals are thought to have come from deep in the crust. During metamorphism in the lower crust some rocks melt and these melts can transport metals upward to ultimately form ore deposits. At slightly cooler temperatures, metamorphism leads to liberation of fluids with the capacity to dissolve metls and transport them into the upper curst. By conducting experiments and comparing the results with natural rocks, this project will investigate the effects of metamorphism on metal distribution in the lower crust.
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