U.S. Geological Survey, National Ice Core Lab,, Denver, co 80225 United States
U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, WA 98683 United States
Deep Geological Environments Research Center, National Institute of Advanced Industrial Science and Technology Deep Geological Environments Research Center, National Institute of Advanced Industrial Science and Technology, Center 7, 1-1-1, Higashi, Ibaraki, Tsukuba, 305-8567 Japan