CERCAMS WORKSHOP

MAY 20, 2003

THERMAL AUREOLE (pluton-related) GOLD

Dr Vic Wall

BRIEF PROFESSIONAL C.V.

Venue: Natural History Museum, Mineralogy Department,

Cromwell Road, South Kensington, London

Thermal Aureole Gold (TAG) deposits are localised in the roof zones and tops of felsic plutons and are temporally related to the emplacement and cooling of such plutons. Broadly distributed in space and time, the TAG association hosts a significant proportion of the world's gold inventory including several world class goldfields, eg Muruntau (Uzbekistan), Granites-Tanami and Telfer (Australia), the Tintina Belt (Alaska-Yukon) and others.

The gold fertility of some pluton roof zones results from the large volume of hydrothermal fluids liberated by magma crystallisation and thermal metamorphism, related heat fluxes and also fluid flow focusing structures active during and after pluton emplacement. Giant TAG deposits may form in and over sill/laccolith-shaped plutons, emplaced late- or post-tectonically in fold-thrust belts. Within the pluton roof zones, a range of characteristic thermal, mechanical and chemical environments may host major deposits comprising vein networks and/or disseminated mineralization in reactive hosts.

The TAG association exhibits systematic geochemical, mineralogical and alteration patterns relating to pluton proximity and timing of mineralization relative to pluton cooling. TAG ore-forming systems are distinct from, but transitional to epithermal, porphyry, Carlin-style and "orogenic" mesothermal systems. The significance of this distinctive class of pluton-related gold deposits is not yet broadly appreciated in Western Block geoscience.

This half day workshop will focus on the essentials of gold fertile TAG environments worldwide including:

• regional geological, geophysical and geodynamic characteristics;
• pluton emplacement dynamics and magmatic links;
• the structural, thermal and chemical evolution of ore-forming systems at deposit to district scales;
• practical targeting criteria and target generation.

utilising examples from Australia, North America, Asia and West Africa.

Vic Wall is an internationally renowned geoscience consultant with over thirty years of industry and research experience. Following his career in Australian and North American academe, Vic held senior positions in major mining and junior exploration companies, further developing his expertise in regional geology, project generation and concept development for precious and base metal systems, worldwide. Currently he is a Principal of Taylor Wall & Associates, which (with partner Fractal Graphics) won the Goldcorp Challenge (2001).

BRIEF PROFESSIONAL C.V.

Dr Vic Wall is Principal of Taylor Wall & Associates, specialising in mineral project generation and evaluation and providing geoscientific consulting services, worldwide. Prior to Taylor Wall & Associates, Vic was Director of Exploration (Australasia) for Southwestern Gold and Chief Geologist (Project Generation) for M.I.M. His decade in exploration followed twenty years of research and teaching at Monash University, plus visiting positions at Penn State, Arizona State and the University of Michigan, and more recently Adjunct Professor, University of Queensland.

A world class geologist, internationally recognised by the exploration and research industries, Vic has high level expertise in most styles of precious and base metal deposits and a broad-based understanding of environments prospective for such deposits. He has worked extensively in Australia, Asia, the Americas and Africa and is credited with key roles in the discovery, identification or acquisition of several significant deposits as well as 150 geoscientific publications. In 2001 Vic (with partner Fractal Graphics) won the Goldcorp Challenge.