1. Energy and Geoscience Institute; University of Utah; Salt Lake City Utah USA
2. Department of Geology and Geophysics; Woods Hole Oceanographic Institution; Woods Hole Massachusetts USA
3. Crustal Geophysics and Geochemistry Science Center; U.S. Geological Survey, Denver Federal Center; Denver Colorado USA
4. Department of Physics; University of Alberta; Edmonton Alberta Canada
5. Department of Physics; The College of New Jersey; Ewing New Jersey USA