1. Macalester College, Geology Department, Saint Paul, MN 55105, USA
2. Stony Brook University, Department of Geosciences, Stony Brook, NY 11794, USA
3. University of California Santa Cruz, Earth and Planetary Sciences Department, Santa Cruz, CA 95064, USA
4. University of Hawai‘i at Mānoa, Hawai‘i Institute of Geophysics and Planetology, Honolulu, HI 96822, USA