2.7 Billion Year Old Mt. St. Helens of Northern Minnesota : Petrography and Geochemistry of the Neoarchean Gafvert Lake Sequence

Abstract

The Gafvert Lake sequence comprises part of the Vermilion District in the Wawa-Abitibi Terrane in northeastern Minnesota and is located in Minnesota's newest state park, Lake Vermilion State Park. The Neoachean Gafvert Lake sequence is a 2.7 billion year old volcanic and plutonic complex similar to those found in modern subduction zone settings. The purpose of this study was to provide a better understanding of the geological, volcanological, geochemical, tectonic and mineralization processes, as well as age relationships associated with its development.