U.S. Geological Survey Astrogeology Research Team, 2255 N. Gemini Dr., Flagstaff, AZ 86001, USA
Scripps Institution of Oceanography University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA; NASA Goddard Spaceflight Center, Greenbelt Rd., Greenbelt, MD 20771, USA
Scripps Institution of Oceanography University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA; University of British Columbia Department of Earth and Ocean Sciences, 6339 Stores Road, Vancouver, BC V6T 1Z4, Canada