Text Box: Superior Upland Introduction | Geologic History | Features | Resources
The Superior Upland province, also sometimes referred to as the Superior Highlands,  covers northeastern Minnesota, northwestern Michigan, and approximately the northern half of Wisconsin.  Definitive boundaries for this province have been difficult to establish, and attempts to determine boundaries that would include only Precambrian rocks, the main type of rocks in the region, have been complicated by glacial material that overlies much of the bedrock.  The ruler-straight western border of the province has been rather arbitrarily established. 
The Superior Upland is, in similar fashion to the Adirondacks, a southern extension of the Canadian Shield.  There are several differences, however, between the Superior Upland and Adirondacks provinces.  Most of the Superior Upland is part of the Penokean subdivision of the Shield, and a small part of the northern portion of the province is in the Algoman-Saganagan subdivision, whereas the Adirondacks province is part of the Grenville subdivision of the Canadian Shield.  Most of the Precambrian basement rocks of the Superior Upland are approximately a billion years older than those of the Adirondacks, the former being a part of the central, older portion of the North American Shield.  The topography of the two provinces also contrasts:  the Superior Upland is mostly flat or has gently rolling topography, and hills of a few hundred feet in height are the highest points in the province; the Adirondacks province is largely mountainous. 
Superior Upland Introduction | Geologic History | Features | Resources