*Charline Lormand¹, Georg F Zellmer¹, Naoya Sakamoto², Geoff Kilgour³, Teresa Ubide⁴, Hisayoshi Yurimoto², Alan Palmer⁵, Karoly Nemeth¹, Yoshiyuki Iizuka⁶, Anja Moebis⁵ (1.School of Agriculture and Environment, Volcanic Risk Solutions, Massey University, PO Box 11222, Palmerston North 4442, New Zealand, 2.Isotope Imaging Laboratory, Natural History Sciences, Hokkaido University, Sapporo 060-0810, Japan, 3.GNS Science, Wairakei Research Centre, Private Bag 2000, Taupo 3352, New Zealand, 4.School of Earth and Environmental Sciences, The University of Queensland, Brisbane, QLD 4072, Australia , 5.School of Agriculture and Environment, Department of Soil Science, Massey University, PO Box 11222, Palmerston North 4442, New Zealand , 6.Institute of Earth Sciences, Academia Sinica, 128 Academia Road Sec. 2, Nankang, Taipei 11529, Taiwan)