Department Seminar: Howard Street Robinson Medal Lecture

Using igneous petrology to unravel the tectonic triggers for porphyry mineralization

Dr. Pete Hollings, Professor and Chair, Department of Geology, Lakehead University

Abstract

Recent studies of the magmatic rocks associated with porphyry systems in both continental and island arc environments has shown that the geochemistry of the pre-and syn-mineralization rocks shows systematic variations that can be attributed in some cases to the subduction of aseismic ridges. The role of ridge subduction, either as a source of metals or simply as a cause of flattening and compression, remains to be determined but the fact that ridge subduction is linked to the majority of recent giant porphyry Cu-Mo-Au systems suggests they play a critical role. This talk will examine the evidence for the effects and impact of ridge subduction in Chile and the Philippines.

About Dr. Hollings

Dr. Hollings completed his Ph.D. at the University of Saskatchewan in 1998 where he investigated the geochemistry of the 2.7-3.0 Ga Uchi Subprovince from Red Lake to Pickle Lake. During a two-year NSERC funded postdoctoral fellowship at CODES Dr. Hollings participated in a multi-disciplinary research project investigating the genesis of giant copper-porphyry deposits in Chile. As a faculty member at Lakehead University since 2001, Dr. Hollings is continuing his research into the relationship between igneous petrogenesis and mineralisation in Northwestern Ontario, the Philippines and S America. He has published more than 75 peer-reviewed papers on these topics. Hollings is currently the Chair of the Department of Geology and Director of the Centre of Excellence for Sustainable Mining and Exploration, both at Lakehead University. He was appointed an Associate Editor of Mineralium Deposita in 2017.