Who was an American writer responsible for a dissertation concerning  the towns and districts built near sediment formations around Lake Superior?
Iron Range Iron Range refers collectively or individually to a number of elongated iron-ore mining districts around Lake Superior in the United States and Canada. Despite the word "range," the iron ranges are not mountain chains, but outcrops of Precambrian sedimentary formations containing high percentages of iron. These cherty iron ore deposits are Precambrian in age for the Vermilion Range, while middle Precambrian in age for the Mesabi and Cuyuna Ranges, all in Minnesota. Similarly, the Gogebic Range in Wisconsin and the Marquette Iron Range and Menominee Range in Michigan. Natural ores and concentrates were produced from 1848 until the mid 1950s, when taconites and jaspers were concentrated and pelletized started to become the major source of iron production.
Sigurd F. Olson Sigurd Ferdinand Olson (April 4, 1899 – January 13, 1982) was an American author, environmentalist, and advocate for the protection of wilderness. For more than thirty years, he served as a wilderness guide in the lakes and forests of the Quetico-Superior country of northern Minnesota and northwestern Ontario. He was known honorifically as "the Bourgeois" — a term the voyageurs of old used of their trusted leaders.