1. Divisions of potential fracture permeability, based on distribution of structures and linear features in sedimentary rocks, northern Great Plains--Rocky Mountains region of North Dakota, South Dakota, Wyoming, and northern Nebraska Yale Public content 1986. 2002-06-01T04:00:00Z. 2002-06-01T04:00:00Z. Geological Survey (U.S.). The Survey ; For sale by Map Distribution. English. Public. Great Plains. and Rocky Mountains region.