北海道地区自然災害科学資料センター報告Vol.32, 3-10, 2019໭ᾏ㐨⫹⫹᣺ᮾ㒊ᆅ㟈㸦㸦2018 ᖺ 9 ᭶ 6 ᪥㸧࡛ฟ⌧ࡋࡓᄇᄇ◁ࡢ≉≉ᚩ
Sedimentary structure and composition of sand blows and sanddikes formed by the 2018 Iburi--Tobu Earthquake, Hokkaido, Japanすᮧ ⿱୍ 1 㸪༓ⴥ ᓫ 21㸪໭ᾏ㐨኱Ꮫ⌮Ꮫ◊✲㝔ᆅ㟈ⅆᒣ◊✲ほ ࢭࣥࢱ࣮2㸪⛅⏣┴❧኱Ꮫ⏕⏕≀㈨※⛉Ꮫ㒊Yuichi Nishimura1 㸪Takkashi Chibba2
1㸪Instiitute of Seismology and Volcanology, Graduate School of Science, Hokkaido
University2㸪Faculty of Bioresource Sciences, Akita Prefectural UniversityyAbstract
The M6.7 Hokkaido Iburi-Tobu Earthquake of September 6th, 2018, left sand blows and sanddikes result from liquefaction. We investigated distribution, shape, sedimentary structure andcomposition of the new sandy deposits at Atsuma and Mukawa. Size of the sand blows varies fromseveral tens of centimeters to several meters in diameter, and they are composed by fine to coarse
sand, mud, pebbles and various size of pumice. The sand dikes that extend through the top soil are
not straight, they are curved or bent along the boundary of the inhomogeneous medium around them.
The width of them vary from 1 mm to 10 cm, and they are filled with the same materials as thosecame out at the final stage of the ejection. The precise description of the new sand blows and sanddikes can provide a better understanding of the liquefaction process and also can be useful for theidentification and evaluation of paleo liquefaction deposits.
Key Words: Iburi-Tobu Earthquake. Liquefaction, Sand blow, Sand dike࣮࣮࢟࣡ࢻ㸸⫹⫹᣺ᮾ㒊ᆅ㟈㸪㸪ᾮ≧໬㸪ᄇ
ᄇ◁㸪ᄇᄇ◁ୣ㸪◁◁⬦1䠊䛿䛨䜑䛻
2018 ᖺ 9 ᭶ 6 ᪥㸪໭ᾏ㐨⫹᣺ᆅ᪉ᮾ㒊ࢆ㟈※࡜ࡍࡿ࣐ࢢࢽࢳ࣮ࣗࢻ 6.7 ࡢᆅ㟈㸦௨ୗ㸪⫹᣺ᮾ㒊ᆅ㟈㸧ࡀⓎ⏕ࡋࡓ㸬ࡇࡢᆅ㟈࡛ࡣ㸪㟈※࡟㏆࠸ཌ┿⏫㸪ࡴ࠿ࢃ⏫㸪Ɫᑠ∾ᕷࡔࡅ࡛࡞ࡃ㸪ᑡࡋ㞳ࢀࡓᮐᖠᕷ࡛ࡶᾮ≧໬࡟ࡼࡿ⿕ᐖࡀ࠶ࡗࡓ㸬ᡃࠎࡣ㸪⫹᣺ᮾ㒊ᆅ㟈࡟క࠺ᾮ≧໬࡟ࡼࡾᙧᡂࡉࢀࡓᄇ◁࡟ࡘ࠸࡚㸪ᙧ≧ࡸᵓ㐀㸪ᵓᡂ≀࡞࡝ࡢᇶᮏⓗ࡞≉ᚩࢆㄪ࡭ࡓ㸬ᄇ◁ࡣᆅ㟈࡟ࡼࡿᙉ㟈ືࡢ⑞㊧࡛࠶ࡾ㸪ᆅᒙ୰࡟ṧࡉࢀࡓᄇ◁ሁ✚≀ࡣᆅ㟈άືࡢ㛗ᮇホ౯࡟࡜ࡗ࡚㔜せ࡞᝟ሗࢆࡶࡓࡽࡍ 1)㸬≉࡟⫹᣺ᮾ㒊ᆅ㟈ࡢࡼ࠺࡟ὠἼࢆకࢃࡎ㸪ࡲࡓ㟈※ࡀ῝ࡃᆅ⾲᩿ᒙࡀ⌧ࢀ࡞࠸ᆅ㟈࡟࠾࠸࡚ࡣ㸪ᄇ◁ሁ✚≀ࡣ㝈ࡽࢀࡓ≀ドࡢ୍ࡘ࡜ࡋ࡚㈗㔜࡛࠶ࡿ㸬⪃ྂᏛࡢⓎ᥀⌧ሙ࡛ᄇ◁ࡀぢࡘ࠿ࡿࡇ࡜ࡣᑡ࡞ࡃ࡞࠸ 1) 2)㸬ᮐᖠᕷ࡛ࡶ㸪ᄇ◁ࡢ⑞㊧ࢆ 1834 ᖺ㸦ኳ3ಖ 5 ᖺ㸧࡟▼⊁ᆅ᪉࡟⿕ᐖࢆࡶࡓࡽࡋࡓᆅ㟈࡜⤖ࡧࡘࡅࡓࡾ㸪ࡲࡓ」ᩘࡢᄇ◁ሁ✚≀ࡢᖺ௦ࢆ᥎ᐃࡋ࡚ᆅ㟈ࡢⓎ⏕ᒚṔࢆ᥈ࡿ◊✲ࡀ⾜ࢃࢀ࡚ࡁࡓ 2) 3)㸬ࢽ࣮ࣗࢪ࣮ࣛࣥࢻ࡛ࡣ 2010 ᖺࡢࢡࣛ࢖ࢫࢺࢳ࣮ࣕࢳᆅ㟈ࡢⓎ⏕ࢆᶵ࡟㸪᪂ࡋࡃ࡛ࡁࡓᄇ◁ࡢ⑞㊧ࡀヲࡋࡃㄪᰝࡉࢀ㸪ࡉࡽ࡟ྂ࠸᫬
௦ࡢ⑞㊧ࢆ᥈ࡋ࡚ᆅ㟈άືࢆホ౯ࡍࡿ◊✲ࡀ㐍ࡵࡽࢀ࡚࠸ࡿ 4)㸬

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࡟࡞ࡿ࡜⪃࠼ࡽࢀࡿ㸬ᄇ◁ࡢ⑞㊧ࢆᆅ㟈Ⓨ⏕ࡢ㛗ᮇホ౯࡟⤖ࡧࡘࡅࡿ࡟ࡣ㸪ᄇ◁ሁ✚≀ࡢᖺ௦ࢆ᥎ᐃࡍࡿᚲせࡀ࠶ࡿ㸬ࡇࡢព࿡࡛ࡣ㸪ᆅ⾲࡟ᙧᡂࡉࢀࡿᄇ◁ୣࡀ᭱ࡶከࡃࡢ᝟ሗ㔞ࢆ᭷ࡋ࡚࠸ࡿ㸬ࡼࡗ࡚㸪ᄇ◁ୣࡢ≉ᚩࢆ⌮ゎࡋㄆᐃᡭ㡰ࢆ☜❧ࡍࡿࡇ࡜ࡣ㸪ᆅ㉁Ꮫࡔࡅ࡛࡞ࡃᆅ㟈Ꮫࡢศ㔝࡟࠾࠸࡚ࡶ㔜せ࡛࠶ࡿ㸬୍᪉㸪ᆅ⾲࡟ᙧᡂࡉࢀࡓሁ✚≀ࡣ㸪ὠἼሁ✚≀࡜ྠᵝ࡟౵㣗ࡢᙳ㡪ࢆཷࡅࡸࡍ࠸㸬ࡼࡗ࡚ᙧᡂ㐣⛬࡟ຍ࠼࡚ᇙἐࡋ࡚ᆅᒙ࡜ࡋ࡚ṧࡿࡲ࡛ࡢ⥆ᡂ㐣⛬ࡶ⌮ゎࡋ࡞ࡃ࡚ࡣ࡞ࡽ࡞࠸㸬ᮏ◊✲࡛ࡣ㏣㊧ㄪᰝࢆᛕ㢌࡟࠾ࡁ㸪ᄇ◁ୣࡸ◁⬦ࢆㄪ࡭ࡿࡓࡵࡢ᥀๐ࡣ᭱ᑠ㝈࡟࡜࡝ࡵࡓ㸬

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⑞㊧ࡶㄆࡵࡽࢀࡓ㸬ࡇࢀࡽࡢᙧ≧ࡣ㸪ࢫࢣ࣮ࣝࡣ㐪࠺ࡀⅆᒣᆅᙧ࡟ぢࡽࢀࡿ≉ᚩ࡜ࡼࡃఝ࡚࠸ࡿ㸬 ᄇ◁ୣࢆᵓᡂࡋ࡚࠸ࡿࡢࡣ◁㸪Ἶ㸪㍍▼࡛࠶ࡿ㸬㍍▼ࡣᄇ◁ୣࡢ⦕㒊࡟㞟✚ࡋ࡚࠸ࡿࡇ࡜ࡀከ
࠸㸬㍍▼ࢆ୺య࡜ࡍࡿᄇฟ≀ࡀ㸪ࡑࡢᚋ࡟ฟ࡚ࡁࡓ◁ࢆ୺య࡜ࡍࡿᄇฟ≀࡟そࢃࢀࡓࡼ࠺࡟ぢ࠼ࡿ㸬◁ࡣἾ࡜୍⥴࡟ᅛࡲࡗ࡚࠸࡚ὶືᛶࡣప࠸㸬

5

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㸬7ᆅⅬ  ཌ┿⏫ࡢᾏ὾බᅬ࿘㎶࡛ࡣ㸪ཌ┿ᕝᕥᓊࡢἙཱྀ㏆ࡃ࠿ࡽᾏ὾බᅬࡢ㥔㌴ሙ࡟࠿ࡅ࡚ᑠࡉ࡞ᄇ◁ୣࡀ↓ᩘ࡟ศᕸࡋ࡚࠸ࡓ㸦ᅗᅗ 㸧㸬ᆅⅬ 1 ࡜ẚ࡭࡚㸪┤ᚄᩘ m つᶍࡢࡶࡢࡣᑡ࡞ࡃ㸪࡯࡜ࢇ࡝ࡀ 1m ௨ୗ࡛࠶ࡿ㸬┤⥺࡟ἢࡗ࡚Ⅼᅾࡍࡿሙྜࡀከ࠸㸬ᆅⅬ 1 ࡟ẚ࡭࡚㸪ᄇ◁ୣࡣⷧࡃ᭱኱࡛ࡶ 10 cm௨ୗࡢࡶࡢࡀከ࠸㸬ᩳ㠃࡟ἢࡗ࡚Ἶࡢࡳࡀⷧࡃᗈࡀࡗ࡚࠸ࡿࡶࡢࡶከࡃ㸪ᄇ◁ࡢὶືᛶࡀ㧗࠿ࡗࡓࡇ࡜ࡀ᥎ ࡉࢀࡿ㸬 ᄇ◁ୣࢆᵓᡂࡋ࡚࠸ࡿࡢࡣ୺࡟◁㸪Ἶ㸪㍍▼࡛࠶ࡿ㸬㍍▼ࢆྵࡴᄇ◁ࡢሙྜ㸪ᆅⅬ 1 ࡜ྠᵝ࡟㸪㍍▼ࡣᄇ◁ୣࡢ⦕㒊࡟㞟✚ࡍࡿഴྥࡀ㢧ⴭ࡛࠶ࡗࡓ㸬ヲࡋࡃぢࡿ࡜㸪ᄇ◁ୣࡢᗏ㒊࡟㍍▼ࢆከࡃྵࡴᒙࡀ࠶ࡾ㸪ࡑࢀࡀ⥆࠸࡚ᄇฟࡋࡓ◁ࢆከࡃྵࡴᄇฟ≀࡟そࢃࢀࡓࡾ㸪࠶ࡿ࠸ࡣࡑࡢὶࢀ୍࡛
㒊ࡀ౵㣗ࡉࢀࡓࡾࡋ࡚࠸ࡿ㸬୍᪉㸪ཌ┿ᕝࡢἙཱྀ㏆ࡃࡢ㝈ࡽࢀࡓሙᡤ࡛㸪┤ᚄ 1 cm ௨ୗࡢῈửࡢ࠸࠸෇♟ࢆ୺య࡜ࡍࡿᄇ◁ࡀぢࡽࢀࡓ㸬ᆅⅬ  ࡴ࠿ࢃ⏫ộぢᆅ༊ࡢᾏᓊἢ࠸ࡢపᆅ࡟ࡣ㸪ᆅⅬ 2 ࡜ྠᵝ㸪࠶ࡲࡾ኱ࡁࡃ࡞࠸ᄇ◁ୣࡀ↓ᩘ࡟ฟ⌧ࡋࡓ㸦ᅗᅗ 㸧㸬㜵₻ሐࡢ㏆ࡃ࡛ࡣ㸪ᩘ m 㛫㝸࡛ᖹ⾜࡞ட⿣ࡀ⌧ࢀ㸪୍㒊㸪ᑠつᶍ࡞ࢢ࣮ࣛ࣋ࣥࢆᙧᡂࡋ࡚࠸ࡿ㸬ᄇ◁ࡣࡇ࠺ࡋࡓட⿣࠿ࡽ྿ࡁฟࡋ㸪ᩳ㠃࡟ἢࡗ࡚ὶࢀୗࡗ࡚࠸ࡿ㸬ᆅ㟈ࡢ┤ᚋ㸦9
᭶ 8 ᪥㸧࡟ゼࢀࡓ㝿࡟ࡣ㸪⦆ࡸ࠿࡞พᆅࡢᗏ࡟ᙧᡂࡉࢀࡓᄇ◁ୣࡀ㸪࿘㎶࠿ࡽᄇฟࡋࡓἾỈ࡟ἐ
ࡋࡓ⑞㊧ࡶㄆࡵࡽࢀࡓ㸬 ᄇ◁ୣࡢᵓᡂ≀ࡣ㸪◁㸪Ἶ㸪ࡑࡋ࡚㍍▼࡛࠶ࡿ㸬ᆅⅬ 1㸪2 ࡜ྠᵝ࡟㸪㍍▼ࡣᄇ◁ୣࡢ⦕㒊࡟ከࡃぢࡽࢀࡿ㸬ಶࠎࡢᄇ◁ୣࡢ⾲ᒙ࡟ぢࡽࢀࡿᄇฟ≀㸪ࡍ࡞ࢃࡕ㸪ྛᄇ◁ࡢ᭱⤊ࢫࢸ࣮ࢪ࡛྿ࡁฟ
ࡋࡓࡶࡢࡣ㸪ࡍࡄ㏆ࡃࡢᄇ◁ୣ࡛ࡶ஫࠸࡟␗࡞ࡗ࡚࠸ࡿሙྜࡀ࠶ࡿ㸦ᅗᅗ D㸧㸬ᆅⅬ  ࡴ࠿ࢃ⏫ộぢ⁺ ࠿ࡽ໭࡟⥆ࡃᾏᓊἢ࠸࡟ࡶ㸪ᑠつᶍ࡞ᄇ◁ୣࡀከᩘ⌧ࢀࡓ㸦ᅗᅗ 㸧㸬≉ᚩࡢ୍ࡘ࡟㸪◁὾࡟ࡶከࡃࡢᄇ◁ୣࡀᙧᡂࡉࢀࡓࡇ࡜࡛࠶ࡿ㸬ࡇࡢᾏᓊ࡛ࡣᆅ㟈ࡢᩘ᪥๓࡟Ⲩኳ࡟ࡼࡿ㧗ἼࡀⓎ⏕ࡋ㸪ὶᮌࡀᡴࡕୖࡆࡽࢀ㸪ࡉࡽ࡟ࡑࡢὶᮌࡢ୍㒊ࡣ㧗Ἴ࡛㐠ࡤࢀࡓ◁࡟ᇙࡲࡗ࡚࠸ࡓ㸬ᄇ◁ୣ࡟ࡣ㸪ࡇࡢ㧗Ἴሁ✚≀࡜ᛮࢃࢀࡿ◁ᒙࡢୖ࡟ᙧᡂࡉࢀࡓࡶࡢࡶ࠶ࡿ㸬ᄇฟཱྀࡸட⿣࠿ࡽᄇฟࡋࡓἾỈࡀᩳ㠃࡟ἢࡗ࡚ᾏ࡟ὶධࡋ࡚࠸ࡿሙᡤࡶ࠶ࡗࡓ㸬ᄇ◁ୣࡣ◁὾࠿ࡽ⥆ࡃ◁ୣ⫼ᚋࡢపᆅ࡟ࡶⅬᅾࡋ࡚࠸ࡿ㸬࡞࠾㸪◁὾࡟ᙧᡂࡉࢀࡓᄇ◁ࡢ⑞㊧ࡣ㸪9 ᭶ 28 ᪥࡟ࡣἼ࡟Ὑࢃࢀ࡚ᾘኻࡋ࡚࠸ࡓ㸬 ᄇ◁ୣࡢᵓᡂ≀ࡣ㸪࡯࡜ࢇ࡝ࡀ◁࡜Ἶ㸪㍍▼ࡔࡀ㸪┒ᅵࡢୖ࡟┤ᚄ 2-3 cm ࡢゅ♟ࢆྵࡴᄇ◁ୣࡀ࡛ࡁ࡚࠸ࡿ࡜ࡇࢁࡶ࠶ࡗࡓ㸬ᄇ◁࡜ᾏ὾◁ࡸ࿘㎶ࡢ◁ୣ◁ࢆẚ࡭ࡿ࡜㸪ᄇ◁࡟ࡣ◁⢏Ꮚ࡟ຍ࠼࡚㸪ࡼࡾ⣽࠿࠸Ἶࢧ࢖ࢬࡢ⢏Ꮚࡀከࡃྵࡲࢀ࡚࠸ࡿ㸬ࡑࡢࡓࡵ㸪ᄇ◁ୣࡣ஝⇱ࡍࡿ࡜ᅛࡃ⥾ࡲࡿ㸬ࡇࡢࡓࡵ㸪ᄇ◁ୣࡣᾏ὾ࡢ◁࡜ẚ࡭࡚㢼࡟ࡼࡿ౵㣗ࡢᙳ㡪ࡣཷࡅ࡟ࡃ࠸㸬11 ᭶ࡢㄪᰝ᫬࡟ࡶ㸪ከࡃࡢᄇ◁ୣࡀᙧᡂ᫬ࡢᙧ≧ࢆಖࡗ࡚࠸ࡿᵝᏊࡀ☜ㄆ࡛ࡁࡓ㸬

4䠊◁⬦ࡢᙧ≧࡜ᵓᵓᡂ≀ ◁⬦ࡢᙧ≧ࢆぢࡿࡓࡵ㸪ᄇ◁ୣࡢ୰ᚰ࠿ࡽ㛗ࡉ 50cm ࡢࢪ࢜ࢫ࣮ࣛࢧ࣮ࢆᡴࡕ㎸ࢇ࡛ヨᩱࢆ᥇ྲྀࡋࡓ㸬ほᐹ㠃ࡣட⿣࡟┤஺ࡍࡿ᪉ྥࡢ᩿㠃࡛࠶ࡿ㸬ᅗᅗ  ࡟౛ࢆ♧ࡍ㸬◁⬦ࡣ῝㒊࠿ࡽࡲࡗࡍࡄᆅ⾲ࡲ࡛ఙࡧ࡚࠸ࡿࡢ࡛ࡣ࡞ࡃ㸪࣮࢝ࣈࡋ࡚࠸ࡓࡾ⣽࠿ࡃࢪࢢࢨࢢ࡟ᒅ᭤ࡋ࡚࠸ࡓࡾࡍࡿ㸬◁⬦ࡢᖜ㸪ࡍ࡞ࢃࡕட⿣ࡢᖜࡣ 1 mm ࠿ࡽ 2 cm ࡛࠶ࡾ㸪ྛࠎࡢ◁⬦ࡢෆ࡛ࡶኚ໬ࡍࡿ㸬8 ◁⬦ࡣ◁㸪Ἶ㸪㍍▼࡛‶ࡓࡉࢀ࡚࠸ࡿ㸬ᵓᡂ≀ࡣ◁⬦㛫࡛␗࡞ࡾ㸪ࡲࡓ୍ࡘࡢ◁⬦ࡢ୰࡛ぢ࡚ࡶ୍ᵝ࡛࡞࠸㸬♟ࢧ࢖ࢬࡢẚ㍑ⓗ኱ࡁ࡞㍍▼ࡸ⢒࠸◁⢏Ꮚࡀ㏵୰࡛ワࡲࡗࡓࡼ࠺࡟ぢ࠼ࡿ࡜ࡇࢁ
ࡶ࠶ࡿ㸬◁⬦ࡢᵓᡂ≀࡜῝ࡉ 50 cm ࡲ࡛࡟࠶ࡿ࿘ᅖࡢᅵተࡢᵓᡂ≀࡜ࡣ᫂ࡽ࠿࡟␗࡞ࡿ㸬◁⬦ࡢᖜࡀᑠࡉ࠸ࡇ࡜ࢆ⪃࠼࡚ࡶ㸪ᄇ◁ୣࡢ⤥※ࡣࡼࡾୗ఩ࡢᾮ≧໬ᒙ࡛࠶ࡿ࡜ࡳ࡞ࡋ࡚࠸࠸ࡔࢁ࠺㸬

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ᄇ◁ୣୣࡀᙧᙧᡂࡉࢀࡿ๓ࡢᆅ
ᆅ⾲㸬GG ࡣᆅⅬ 㸪௚ࡣᆅᆅⅬ  ࡛᥇ྲྀࡋࡓ㸬5䠊⪃ᐹ䛸䜎䛸䜑 ཌ┿⏫࡜ࡴ࠿ࢃ⏫࡟ฟ⌧ࡋࡓᄇ◁ୣ࡜◁⬦ὸ㒊ࡢほᐹ⤖ᯝࢆࡶ࡜࡟㸪ᄇ◁ࡢᙧᡂ㐣⛬࡟ࡘ࠸࡚⪃ᐹࡍࡿ㸬ࡲࡎᾮ≧໬ᒙ࡟ࡘ࠸࡚ࡣ㸪࡝ࡢ῝ࡉ࡟࠶ࡿ࠿୙᫂ࡔࡀ㸪ᵓᡂ≀ࡣ◁㸪♟㸪㍍▼ࡀΰྜࡋࡓࡶࡢ࡛࠶ࡿ࡜᥎ࡉࢀࡿ㸬ࡓࡔ㸪ࡇࢀࡽࡢᵓᡂẚࡣሙᡤ࡟ࡼࡗ࡚␗࡞ࡗ࡚࠸ࡿ࡜ᛮࢃࢀࡿ㸬ᄇฟ㡰ᗎࡣ㸪Ἶ㸪㍍▼㸪◁㸪♟ࡢ㡰࡛࠶ࡿࡇ࡜ࡀከ࠸㸬ᾮ≧໬ᒙࡀୖ఩࠿ࡽ㍍▼㸪◁㸪♟ࡢࣘࢽࢵࢺᵓ㐀ࢆ࿊ࡋ࡚࠸ࡓࡢ࠿㸪࠶ࡿ࠸ࡣ㸪ࡇࢀ࠿ࡽΰᅾࡍࡿᒙࡀ࠶ࡗ࡚Ỉ࡛‶ࡓࡉࢀ࡚࠸࡚㸪ᆅ㟈࡛ᾮ≧໬ࡋࡓ㝿࡟⢏Ꮚࡢẚ㔜࡟ᛂࡌ࡚ᒙෆ࡛ศ⣭ࡀ㉳ࡁࡓ⤖ᯝࢆ཯ᫎࡋ࡚࠸ࡿࡢ࠿㸪୧᪉ࡢྍ⬟ᛶࢆ⪃࠼ࡿᚲせࡀ࠶ࡿࡔࢁ࠺㸬 ᄇ◁ୣࡸ◁⬦ࡢᵓᡂ≀ࡸᵓ㐀࡟ࡣ㸪๭ࢀ┠ࡢᙧ≧ࡸࡑࡢᙧᡂ㐣⛬ࡀᙉࡃᙳ㡪ࡋ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿ㸬ᄇฟࡢ࠶ࡿ᫬Ⅼ࡛๭ࢀ┠ࡀワࡲࡗ࡚ࡋࡲ࠼ࡤ㸪ࡑࢀ௨㝆ࡣ⣽࠿࠸⢏Ꮚࡋ࠿ฟ࡚ࡇ࡞࠸㸬ᄇ◁ୣࡸ◁⬦ࡢᵓᡂ≀ࡸᵓ㐀ࡀ㸪ࡈࡃ㏆ࡃࡢࡶࡢྠኈ࡛ẚ࡭࡚␗࡞ࡿࡇ࡜ࡸ㸪๭ࢀ┠࡟ἢࡗ୍࡚ᵝ࡛࡞࠸ࡼ࠺࡟ぢ࠼ࡿࡇ࡜ࡶ㸪ࡇࡢᙧ≧ࡢ」㞧ࡉ࡛࠶ࡿ⛬ᗘࡣㄝ࡛᫂ࡁࡑ࠺࡛࠶ࡿ㸬 ࡇࡢㄪᰝ◊✲ࡢ┠ⓗࡣ㸪㐣ཤࡢᾮ≧໬⑞㊧ࢆㄆᐃࡍࡿᡭ㡰ࢆᵓ⠏ࡍࡿࡇ࡜㸪ࡑࡋ࡚ࡑࡢ㝿ࡢㄢ㢟ࡸ㝈⏺ࢆ⌮ゎࡍࡿࡇ࡜࡟࠶ࡿ㸬௒ᅇ㸪◁࡟㍍▼ࡀΰᅾࡍࡿᒙࡀᾮ≧໬ࡍࡿ࡜≉ᚩⓗ࡞ᄇ◁ୣࡸ◁⬦ࡀṧࡿࡇ࡜ࡀ☜ㄆ࡛ࡁࡓ㸬ᮏ✏ࡣ┠どほᐹ࡟ᇶ࡙ࡃ≉ᚩࢆ➨୍ሗ࡜ࡋ࡚ሗ࿌ࡍࡿࡶࡢ࡛㸪᥇ྲྀࡋࡓ◁ࡢ⢏ᗘ≉ᛶࡸᚤ໬▼ࡢ≉ᚩ㸪㍍▼ࡢ㉳※➼࡟ࡘ࠸࡚ࡣู✏࡟グࡍணᐃ࡛࠶ࡿ㸬ࡲࡓ㸪ᾮ≧໬ᒙࡸᆅ⾲࡟㐩ࡋ࡚࠸࡞࠸◁⬦ࡢ᥀๐ㄪᰝࡶィ⏬୰࡛࠶ࡿ㸬9ཧ⪃ᩥ⊩1) ᐮᕝ᪫  ࠕ㑇㊧࠿ࡽᚓࡽࢀࡓ㐣ཤࡢᆅ㟈᝟ሗࠖ㸪ࠗᆅᏛ㞧ㄅ࠘㸪㸪SS2) ⩚ᆏಇ୍࣭♒㒊୍ὒ࣭ୗᕝᾈ୍࣭୐ᒣኴ  ࠕᮐᖠ௜㏆࡛Ⓨぢࡉࢀࡓከᩘࡢᾮ≧໬㊧࡜⾲ᒙᆅ㉁ࡢ㛵㐃ᛶࠖ㸪
ࠗᆅ㉁ࢽ࣮ࣗࢫ࠘㸪㸪SS3) అᓥ♸୍㑻࣭ᖹᕝ୍⮧  ࠕ໭ᾏ㐨኱Ꮫᵓෆ࡛ほᐹࡉࢀࡓᾮ≧໬㊧୍ඛྐᆅ㟈࡜ᾮ≧໬ᵓ㐀ᙧᡂ㐣⛬ࡢゎㄞ୍ࠖ㸪ࠗά᩿ᒙ◊✲࠘㸪㸪
4) P. Villamor, P. Almond, M. P. Tuttle, M. Giona-Bucci, R. M. Langridge, K. Clark, W. Ries,
S. H. Bastin, A. Eger, M. Vandergoes, M. C. Quigley, P. Barker, F. Martin, and J. Howarth(2016), Liquefaction Features Produced by the 2010–2011 Canterbury Earthquake
Sequence in Southwest Christchurch, New Zealand, and Preliminary Assessment ofPaleoliquefaction Features, Bulletin of the Seismological Society of America, 116, doi:
10.1785/0120150223. 5) ୰⏣ 㧗࣭ᓥᓮ㑥ᙪ (1997)ࠕά᩿ᒙ◊✲ࡢࡓࡵࡢᆅᒙᢤࡁྲྀࡾ⿦⨨㸦Geo-slicer㸧ࠖ㸪ࠗᆅᏛ㞧ㄅ࠘㸪㸪SS㸬10