sentences:  This windy plateau is being developed for commercial wind power, contributing to the state's ranking as third in the nation for wind-generated electricity.Between the river and the plateau are flat prairies atop varying depths of glacial till.In the extreme southwest portion of the state, bedrock outcroppings of Sioux Quartzite are common, with less common interbedded outcrops of an associated metamorphosed mudstone named catlinite.