年代測定値 | K-Ar (isotope dilution; whole rock) Hypersthene hornblende andesite lava flow, EBW-4 1.54 ± 0.11 Ma; Quartz-bg hypersthene hornblende andesite lava flow, 282101, 1.30 ± 0.07 Ma [2]; Hypersthene augite andesite block of lava flow, EBW-1, 1.24 ± 0.08 Ma [2]; Hornblende olivine augite hypersthene andesite lava flow, EBW-2, 1.23 ± 0.07 Ma [2]; Augite hornblende hypersthene andesite lava flow, EBW-3, 1.26 ± 0.07 Ma [2]; Hypersthene augite andesite block of lava flow, EBW-5, 1.19 ± 0.08 Ma [2]; Hypersthene augite andesite block of lava flow collected from talus deposit, 8770903, 1.13 ± 0.07 Ma [2] |