Circum-Superior Belt age of . Another volcanic series in the Marquette Range Supergroup, known as the Gunflint Formation, has an age of . Further geologic units that are related to the Gunflint Formation include the Badwater volcanics and the Kiernan sills. A number of origins have suggested for the Marquette Range Supergroup magmatism. This includes subsidence being driven ahead related to thrusting of the Penokean orogeny or a possible back-arc basin, and lateral flow through the Pickle Crow dikes transported magma from the Fox River Belt area through the Superior craton for placement in the Marquette Range Supergroup. This suggested long-range origin
Ring of Fire (1991 film) Ring of Fire (1991 film) Ring of Fire is a 1991 documentary film in IMAX format. It looks at some of the varieties of volcanism and earthquake activity in the Ring of Fire, around the Pacific Rim. The film runs 40 minutes. The film was jointly presented by the Fort Worth Museum of Science and History in Fort Worth, Texas, the Science Museum of Minnesota in Saint Paul, Minnesota, and the Reuben H. Fleet Space Theater and Science Center in San Diego, California. The film has eight main segments, corresponding to chapters in the DVD release: 1. "Ring of Fire":