Modified Mercalli Intensity Assignments for the May 16, 1909, Northern Plains Earthquake By W.H. Bakun 1 , M.C. Stickney 2 , G. Rogers 3 , and J. Ristau 4 Open-File Report 2010-1185 1 U.S. Geological Survey, Menlo Park, Calif., USA 2 Montana Bureau of Mines and Geology, Butte, Mont., USA 3 Geological Survey of Canada, Victoria, BC, Canada 4 Geological Survey of Canada, Victoria, BC, Canada (now at GNS Science, Lower Hutt, New Zealand) U.S. Department of the Interior U.S. Geological Survey