Tephra of the World Age is in 1000 years going back from 2000 AD. Magnitude is defined as M = log m - 7, where m is the mass of magma in kg. Tephras larger than M6.0 (for Japan only, M > 6.5) are listed here. Age Magnitude Volcano-Tephra 0.088 6.5 Katmai Alaska America-N 0.117 6.1 Kurakatau Indonesia 0.185 7.1 Tambora Indonesia 0.34 6.3 Long Island PNG 0.42 6.0 Billey Mitchell PNG 0.575 6.8 Kuwae Vanuatu Pacific-S 1.054 7.4 Baitoushan-Tomakomai Korea/China 1.15 7.4 Dakataua PNG 1.3 6.1 Bona-White River E lobe Alaska America-N 1.4 6.0 Opala Kamchatka 1.464 6 Rabaul PNG 1.584 7.1 Kurakatau Indonesia 1.7 6.2 Ksudach Kamchatka 1.74 6.7 Ilopango El Salvador America-C 1.82 6.7 Taupo New Zealand 1.9 6.2 Bona-White River N lobe Alaska America-N 2.22 6.9 Masaya Nicaragua America-C 2.4 6.7 Okmok II Aleutian America-N 2.6 6.8 Witori PNG 3.5 6.6 Vesuvius-Z1 Italy Mediterranean 3.6 6.8 Santorini-Minoan Greece Mediterranean 3.6 6.9 Aniakchak II Alaska America-N 3.60 6.2 Taupo-Waimihia New Zealand 4 6 Rabaul-Raluan PNG 4.0 6.7 Veniaminof Alaska America-N 4 6.7 Deriba Sudan Africa 4 6.3 Long Island PNG 5 6.5 Kaguyak Alaska America-N 5 6.5 Black Peak Alaska America-N 5.5 6 Akutan Aleutian America-N 6 6.9 Masaya Nicaragua America-C 6.9 6.0 Ksudach Kamchatka 7 7.0 Tao Rusyr Kuriles 7 5.7 Campi Flegrei-Agnano Italy Mediterranean 7 6 Aniakchak I Alaska America-N 7.330 8.1 Kikai-Akahoya Kyushu Japan 7.5 6.4 Kutcharo Mashu-f/j Hokkaido Japan 7.7 6.8 Crater Lake-Mazama Oregon America-N 7.8 6.3 Khangar Kamchatka 7.8 5.5 Crater Lake-Llao Rock Oregon America-N 8.1 6.4 Academii Nauk Kamchatka 8.5 7.0 Kurile Lake Kamchatka 8.5 6 Makushin Aleutian America-N 8.6 6.0 Karymsky Kamchatka 9 6.7 Okmok I Aleutian America-N 9.1 6 Karkar PNG 10 6.7 Fisher Aleutian America-N 10 6.7 Uturyo-Oki Korea 10 7.1 Semisopochnoi Aleutian America-N 10.5 7 Lvinaya Past Kuriles 12 6.2 Laacher See Germany 12 6.1 Maly Semiachik Kamchatka 12 5 Glaciar Peak-Chiwawa Bed B Washington America-N 15 6.7 Towada-L Honshu Japan 15 6.7 Ksudach Kamchatka 16 7.4 Long Island PNG 16 6.0 Campi Flegrei-Napolitan Yellow Italy Mediterranean 20 7.1 Zavaritsky Kuriles 20 6 Etna-Y1 Italy Mediterranean 23.4 5 Cascade-Trego Hot Springs America-N 24 6 Santorini-Y2 Greece Mediterranean 25 7.0 Opala Kamchatka 25 6.4 Apoyo Nicaragua America-C 26 7.4 Batur-Bali Indonesia 26 8.3 Aira-Tanzawa Kyushu Japan 26.5 7.9 Taupo-Oruanui New Zealand 27 6.7 Towada-N Honshu Japan 28 6 Campanian-Y3 Italy Mediterranean 30 6.4 Roseau Dominica Caribbean 32 6 Santorini-Y4 Greece Mediterranean 35 6.5 Ischia-Citara Italy Mediterranean 37 7.3 Alban Hills Italy Mediterranean 38 7.1 Campi Flegrei-Campanian Italy Mediterranean 39 6.1 Qualibou St. Lucia Caribbean 40 7 Campi Flegrei?-C13 Italy Mediterranean 40 7 Kutcharo-1 Hokkaido Japan 40 6.8 Ksudach Kamchatka 40 7.1 Coatepeque El Salvador America-C 41 7.2 Shikotsu-1 Hokkaido Japan 42 6.4 Krasheninnikov Kamchatka 48 6.8 Cinque Denti Italy Mediterranean 50 6 Rabaul-Malaguna PNG 50 7.3 Gorely Khrebet Kamchatka 50 6.9 Daisen-Kurayoshi Honshu Japan 50 6 Pantelleria-Y6 Italy Mediterranean 50 6.3 Mount St. Helens-C Washington America-N 53 7.4 Haroharo/Okataina-Rotoiti New Zealand 53 6.6 Zenigame-Menagawa Hokkaido Japan 53 7.1 Ischia Italy Mediterranean 60 7 Campi Flegrei?-Y7 Italy Mediterranean 64.1 6.5 Shikotsu-7/10 Hokkaido Japan 65 6 Olema America-N 70 6 Aeolian-Y8 Italy Mediterranean 70 6 Crater Lake-Pumice Castel Oregon America-N 74 8.8 Toba-Youngest Indonesia 84 7.8 Atitlan III-Los Chocoyos Guatemala America-C 86.9 7 Kutcharo-2/3 Hokkaido Japan 87 8.4 Aso-4 Kyushu Japan 90 6.5 Aira-Fukuyama Kyushu Japan 92 6 Helenic-X1 Greece Mediterranean 95 6.9 La Primavera-B Mexico America-C 95 7.5 Kikai-Tozurahara Kyushu Japan 95 6 Campanian-X2 Italy Mediterranean 99 6.6 Ontake-1 Honshu Japan 100 8.0 Kurile Lake-Golygin Kamchatka 100 7.2 Vulsini-Latera Italy Mediterranean 100 6.7 Ugashik Alaska America-N 102 6 Aeolian-X3 Italy Mediterranean 103 7 Ata Kyushu Japan 103 6.7 Sanbe-Kituki Honshu Japan 105 7.4 Toya Hokkaido Japan 105 6 Etna-X4 Italy Mediterranean 110 7.5 Emmons Lake?-Old Crow Alaska America-N 110 6 Campanian-X5 Italy Mediterranean 114 6.8 La Veccia Italy Mediterranean 115 7 Aso-3 Kyushu Japan 115 6 Campanian-X6 Italy Mediterranean 140 7.7 Rotorua-Mamaku New Zealand 145 6 Roman-W1 Italy Mediterranean 150 7.1 Cordillera Nevada Chile America-S 160 7.8 Akan Hokkaido Japan 160 6 Helenic-V1 Greece Mediterranean 165 6 Roman-V2 Italy Mediterranean 175 6 Helenic-V3 Greece Mediterranean 178 6.2 Hakone-TAm5 Honashu Japan 200 7.5 Okataina-Matahina New Zealand 225 7.5 Haroharo New Zealand 230 8 "Worzel"-L Colombia/Ecuador America-S 240 7.2 Amatitlan-T Guatemala America-C 250 6 Onikobe-Ikezuki Honshu Japan 250 7 Ata-Torihama Kyushu Japan 270 7 NZ-E New Zealand 280 7.2 Maninjau Indonesia 285 8 Aso-1 Kyushu Japan 300 8 Taupo-Whakamaru(group) New Zealand 300 7.7 Vulsini-Bolsena Italy Mediterranean 310 7 NZ-D New Zealand 340 7.5 Kakuto Kyushu Japan 350 7 Broken Top?-Loleta Oregon America-N 360 7 Lassen-Rockland California America-N 360 7 Hakkoda-2 Honshu Japan 365 7 Kyushu-Hikage 7 Kyushu Japan 385 6.8 Roccamonfina Italy Mediterranean 400 7.0 Polovinka Kamchatka 400 7.3 Stena Soboliny Kamchatka 400 7.1 Uzon Kamchatka 448 7 Baitoushan-Oga Korea/China 450 7.7 Diamantes Chile America-S 500 7.7 Miravalles Costa Rica America-C 500 7 Aira?-Yoshino Kyushu Japan 500 7.5 Corbetti Ethiopia Africa 501 7.1 Toba-Middle Indonesia 540 8 Kobayashi-Sakura Kyushu Japan 600 7 Kakuto?-Hiwaki Kyushu Japan 600 7 Hakkoda-1 Honshu Japan 630 8.4 Yellowstone-Lava Creek Wyoming America-N 650 7 Kuju-Toga Kyushu Japan 670 7 NZ-C New Zealand 730 7 NZ-B New Zealand 780 8.1 Long Valley-Bishop California America-N 800 6 La Pacana-Upper Purico Chile America-S 840 8.1 Toba-Oldest Indonesia 860 7 NZ-A New Zealand 870 8 Shishimuta-Azuki Kyushu Japan 880 8 Kauketea New Zealand 900 8.0 Daisetsu-Tokachi Honshu Japan 900 Long Valley-Glass Mountain D California America-N 910 6.7 Mangakino-Marshall New Zealand 940 8 Shishimuta-Pink Kyushu Japan 970 7.5 Mangakino-Rocky Hill New Zealand 980 8 Kidnappers B New Zealand 1000 Long Valley-Glass Mountain G California America-N 1000 8 Potaka New Zealand 1010 7.5 Mangakino-E New Zealand 1150 7.8 Valles-Upper Bandelier New Mexico America-N 1150 7 Baker-Lake Tapps Washington America-N 1190 6.7 Mangakino-Ahuroa New Zealand 1200 8 Toba-Haranggoal Indonesia 1200 Long Valley-Bailey California America-N 1200 6.0 Mangakino-D New Zealand 1230 7.5 Mangakino-Ongatiti New Zealand 1240 8 Mangatewaiiti New Zealand 1270 7.8 Yellowstone-Mesa Falls Idaho America-N 1300 6.9 La Pacana-Lower Purico Chile America-S 1350 Cascade-Rio Del America-N 1470 7.8 Valles-Lower Bandeliar New Mexico America-N 1590 6.0 Mangakino-C New Zealand 1600 6.7 Mangakino-Ngaroma New Zealand 1630 8 Pakihikura New Zealand 1700 7 Balleny islands?-Eltanin Antarctica 1780 7 Valles-Older New Mexico America-N 2010 8.8 Yellowstone-Hucklebury Ridge Wyoming America-N 2200 8.0 Cerro Galan Argentine America-S