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
Fire ring are not available, but care should be taken as some stones can explode when heated due to trapped gas pockets, thermal expansion, or water contained flashing into steam. Fire ring A fire ring is a construction or device used to contain campfires and prevent them from spreading and turning into wildfires. A fire ring is designed to contain a fire that is built directly upon the ground, such as a campfire. Fire rings have no bottom, and are simply circles made of forged metal, stones, concrete, etc. which surround and contain a fire. Manufactured steel fire rings are available in