1. Crustal Geophysics and Geochemistry Science Center, U.S. Geological Survey, Denver, CO.
2. Department of Earth and Environmental Science, University of Iowa, Iowa Geological Survey, Iowa City, IA.
3. Eastern Mineral and Environmental Resource Science Center, U.S. Geological Survey, Reston, VA.
4. Institute for Rock Magnetism, Department of Earth Sciences, University of Minnesota, Minneapolis, MN.
5. Minnesota Geological Survey, St. Paul, MN.