In-person only Lecture: Oxide Ultramafic Intrusions in MN’s Midcontinent Rift

Presenter: George J. Hudak, Ph. D., P. Geo., P. G., Adjunct Professor of Geology in the Departments of Earth and Environmental Sciences at the University of Minnesota Twin Cities and the University of Minnesota Duluth, and Principal / Economic Geologist,
George Hudak Geosciences P.L.L.C.

Full Title of Lecture: Oxide Ultramafic Intrusions in Minnesota’s Midcontinent Rift – What They Are, How They Form, and a Potential Environmentally Conscientious Processing Scheme to Produce High Value Critical Metal Products

Summary: In recent years, countries around the world have placed an emphasis on developing geologic models and environmentally conscientious methods of refining critical minerals. According to the US Geological Survey, critical minerals are defined as non-fuel metallic or industrial minerals that are vital to a nation’s economic and national security but have supply chains that are vulnerable to disruption. It is well known that Minnesota’s Duluth Complex contains a variety of critical minerals, including copper, nickel, cobalt, and platinum group elements. It is less known that the Duluth Complex also contains numerous enigmatic oxide ultramafic intrusions (OUIs) that contain additional critical mineral resources including titanium and vanadium. This presentation will discuss the geological characteristics of Minnesota’s oxide ultramafic intrusions and will present recent research suggesting that high-value critical mineral products can be produced from these resources in a way that minimizes waste and produces inert waste products.

This lecture will not be recorded for GSM's YouTube Channel.

Biography: Dr. George Hudak is an economic geologist/applied volcanologist with specific expertise in exploration for Precambrian volcanic-, magmatic- and structurally-hosted base-, precious metal-, and critical mineral deposits and their associated mineralizing systems. Develop ment of high value mineral products, more efficient utilization of mineral resources and mining infrastructure, evaluation of large-scale renewable energy storage systems, and development of new models related to the genesis of many mineral deposit types in the Lake Superior area of Canada and the United States have been key components of the industry-, state-, and federally-funded research he has focused on over the last two decades of his career.

Dr. Hudak received his Bachelor’s, Master’s and Ph. D. degrees at Carlton College, the University of Minnesota Duluth, and the University of Minnesota, respectively. Following a one-and-one-half year post-doctoral position at the University of Minnesota Duluth, Dr. Hudak spent 11 years as a Professor in the Geology Department at the University of Wisconsin Oshkosh. He subsequently spent 15 years as a Senior Research Associate and Director of the Minerals and Metallurgy Applied Research Group at the Natural Resources Research Institute (better known as NRRI), an applied research laboratory at the University of Minnesota. After retiring from the NRRI in fall, 2023, Dr. Hudak started George Hudak Geosciences P.L.L.C., a consulting firm in Duluth that specializes in research, strategy and education associated with mineral resources. He also serves as an Adjunct Professor of Geology in the Departments of Earth and Environmental Sciences at the University of Minnesota Twin Cities and the University of Minnesota Duluth, and as a Technical Advisor to Green Bridge Metals Corporation, a junior mineral exploration company currently conducting an exploration program to evaluate critical mineral deposits in Minnesota’s Duluth Complex.

Dr. Hudak holds Professional Geologist licenses in Minnesota and Wisconsin, and a Professional Geoscientist License in the Province of Ontario, Canada. He is a Fellow of the Society of Economic Geologists and has served as a Mentor for the Society since 2008.

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Except as noted, in-person lectures during the winter-spring 2026 semester are Mondays at 7:00 PM CT on the University of Minnesota campus, Keller Hall, Room 3-210.

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