KEGS Ottawa July Meeting

   

The Implications of the Mineral Systems Concept for
Geophysical Exploration: A Perspective 

 

Professor Mike Dentith
University of Western Australia

Thursday, July 13th 
4:30 p.m.

Harrison Hall 
Room 177 
601 Booth Street 

 

Abstract 

There is a consensus that the idea of a mineral systems provides an important conceptual frame work for exploration which will be increasingly undercover.  Similarly, most people accept that geophysics will be increasingly important in mineral exploration in the future.

A mineral system is defined as “… all geological factors that control the generation and preservation of mineral deposits”. Most authors describe a mineral system as comprising a source of metals and/or ligands, a pathway along which fluids transport the metals to a location where they are concentrated (physical trap) and precipitated (chemical trap).  The mineral system concept has important implications for the way geophysics is used in mineral exploration.  For example: 

  1. Additional types of exploration targets are suggested, e.g. the metal source region, the fluid pathway and the trapping site. All of these features are likely to be associated with alteration of the country rocks.  The petrophysical consequences of alteration are generally poorly understood, but an understanding is essential if the associated geophysical responses are to be recognised.
  2. Mineral systems encompass areas far larger than the mineral deposit itself (100s to 1000s of km3) and often extend to mantle depths.  Identifying entire systems requires interpretation of geophysical data at a terrain scale (10000s km2) and also use of geophysical methods that can penetrate to lower crustal and mantle depths (10s km)

Drawing on current research in the Centre for Exploration Targeting (University of Western Australia) this talk will discuss the geophysical responses of common mineral system components, the petrophysics of alteration and the use of deep-penetrating geophysical methods in mineral exploration.  

 

Biography 

Mike Dentith is Professor of Geophysics at the University of Western Australia and a research theme leader in the Center for Exploration Targeting (CET). He has 25 years experience researching, teaching and consulting in mineral exploration geophysics. He is editor of two case study ‘geophysical signatures’ publications on Australian mineral deposits and co-author of the textbook ‘Mineral Exploration Geophysics for Geoscientists’ published by Cambridge University Press.