5 ᵄࠬࡊ࡝࠶࠹ࠖࡦࠣߩ⸃ᨆ߆ࠄ᣿ࠄ߆ߦߥߞߚ␹ᄹᎹ⋵⷏ㇱ࿾ၞߩ⇣ᣇᕈߩⓨ㑆⊛࡮ᤨ㑆⊛ᄌൻᧄᄙ‫ޓ‬੫ ࡮᫜↰ବᡴ
Variations of S-wave anisotropy in space and time in the crust of western Kanagawa, JapanbyRyou HONDA and Toshikazu TANADA㧚ߪߓ߼ߦ࠭ࡓ⸃ߣ߽⺞๺⊛ߢ޽ࠆ‫ޔߚ߹ޕ‬ን჻ጊ‫▫ޔ‬ᩮἫጊ‫ޔ‬દ‫▫ޓ‬ᩮ࡮⿷ᨩ࿾ၞߪࡈࠖ࡝ࡇࡦᶏࡊ࡟࡯࠻ߣ㒽஥ߩࡊ⼺ᄢፉߩਥἫጊ૕ጊ⣻ߩ஥ἫጊߩಽᏓ߆ࠄ߽‫▫ޔ‬ᩮ๟ㄝ࡟࡯࠻ߩⴣ⓭Ꮺߦ޽ߚࠅ‫▫ޔ‬ᩮἫጊ‫࡮✽␹ޔ‬࿖ᐭᵤ㨪ߢߩਥ࿶❗ゲߩᣇะ߇ N30 㩩 W ߢ޽ࠆߎߣ߇ਛ᧛
㧔1969㧕᧻↰ᢿጀᏪߥߤⶄ㔀ߥ࠹ࠢ࠻࠾ࠢࠬࠍ᦭ߔࠆ‫ޕ‬Ukawaߥߤߦࠃߞߡႎ๔ߐࠇߡ޿ࠆ‫ޕ‬

㧔1991㧕ߪ‫ޔ‬ᓸዊ࿾㔡ߩ P ᵄೋേࡔࠞ࠾࠭ࡓ⸃߆ࠄદ⼺‫␹ޓ‬ᄹᎹ⋵᷷ᴰ࿾ቇ⎇ⓥᚲ㧔એਅ‫ޔ‬᷷࿾⎇㧕ߢߪ 1989㧔ᐔඨፉ๟ㄝߩᔕജ႐ࠍផቯߒߚ‫ޕ‬ᓐߪદ⼺ඨፉ⷏஥߆ࠄᚑర㧕ᐕએ㒠‫▫ޔ‬ᩮ࡮⿷ᨩᐔ㊁๟ㄝߦᢙࠠࡠ㑆㓒ߢ 14 ὐ᧲஥ߦ߆ߌߡ‫ޔ‬ን჻ጊઃㄭࠍⷐߣߔࠆᚸᒻߦ࿶❗ゲ߇ർߩ࿾㔡᷹ⷰᣉ⸳ࠍዷ㐿ߒߡ޿ࠆ㧔࿑ 1㧕‫ᧄޕ‬ႎ๔ߢߪ‫ޔ‬᷷᧲ - ධ⷏߆ࠄർ⷏ - ධ᧲ᣇะߦᄌൻߒߡ޿ߊߎߣ߆ࠄ‫ޔ‬࿾⎇ߩ࿾㔡᷹ⷰ✂ߦࠃߞߡᓧࠄࠇߚ࿾㔡ᵄᒻߩ S ᵄࠬࡈࠖ࡝ࡇࡦᶏࡊ࡟࡯࠻ߣ㒽஥ߩࡊ࡟࡯࠻ߩⴣ⓭Ꮺ߇દ⼺ࡊ࡝࠶࠹ࠖࡦࠣߩ⸃ᨆ߆ࠄ‫⇣ޔ‬ᣇᕈߩᤨ㑆࡮ⓨ㑆ಽᏓࠍࡉࡠ࠶ࠢർ⷏ㇱߦሽ࿷ߔࠆߣ⠨߃ߚ‫ޔߚ߹ޕ‬Kaneshimaផቯߒ‫▫ߥ⚦⹦ࠅࠃޔ‬ᩮ࡮⿷ᨩ࿾ၞߩᔕജ႐ߦߟ޿ߡ⠨㧔1990㧕ߦࠃࠆ S ᵄࠬࡊ࡝࠶࠹ࠖࡦࠣࠍ↪޿ߚᔕജ႐ߩ⸃ኤࠍⴕ߁‫ޕ‬ᨆߢߪਤᴛ࿾ၞߩᐢၞᔕജ႐ߪർ⷏ - ධ᧲ᣇะߢ޽ࠅ‫ޔ‬ߎࠇߪ Ukawa㧔1991㧕߿᫜↰㧔2004㧕ߦࠃࠆ࿾㔡ߩࡔࠞ࠾

5 ᵄߩࠬࡊ࡝࠶࠹ࠖࡦࠣߣߪ‫ޓ‬S ᵄߩࠬࡊ࡝࠶࠹ࠖࡦࠣ㧔Shear wave splitting㧕ߣߪ Sᵄ߇⇣ᣇᕈᇦ⾰ਛࠍવ᠞ߔࠆ㓙ߦ‫ޔ‬੕޿ߦ⋥੤ߔࠆᝄേ
ࡌࠢ࠻࡞ࠍ߽ߟ⇣ߥߞߚㅦᐲߩ S ᵄߦಽ㔌ߔࠆ⃻⽎ࠍ޿߁㧔࿑ 2㧕‫ߩߘޕ‬ේ࿃ߣߒߡߪ‫ࠍ⾰‛ޔ‬᭴ᚑߔࠆ㋶‛ߩ‛ᕈ߿࿾ਛߩࠢ࡜࠶ࠢߥߤ߇⠨߃ࠄࠇߡ޿ࠆ‫⇣ޕ‬ᣇᕈᇦ⾰ߩ․ᕈߪ‫ޔ‬వⴕᵄߩᝄേᣇะ㧔LSPD㧕ߣᓟ⛯ᵄߣవⴕᵄߩ೔⌕ᤨ㑆Ꮕ㧔DT㧕ߩ᷹ⷰ߆ࠄផቯߐࠇࠆ‫ޕ‬࿾ਛߦሽ࿷ߔࠆࠢ࡜࠶ࠢߦࠃߞߡࠬࡊ࡝࠶࠹ࠖࡦࠣ߇⿠ߎࠆߣ઒
ቯߔࠆߣ‫ࠢ࠶࡜ࠢޔ‬㕙ߦ⋥੤ߔࠆᣇะߦᝄേߔࠆㆃ޿ Sᵄߣ‫ޔ‬ᐔⴕߥᣇะߩᝄേᣇะࠍ߽ߟㅦ޿ S ᵄߩ 2 ߟߩᵄߦಽ㔌ߔࠆ‫ޕ‬‫ޓ‬࿾ᲖߪᏱߦਥߣߒߡࡊ࡟࡯࠻ߩⴣ⓭ᣇะߦജࠍฃߌߡ޿ࠆ‫ߩߘޕ‬㓙࿾Ზਛߦߪ‫ޔ‬᳓ᐔᦨᄢਥ࿶❗ゲߣᐔⴕߥᓸዊࠢ࡜࠶ࠢ߇↢ᚑߐࠇࠆ‫ޔ߼ߚߩߘޕ‬S ᵄࠬࡊ࡝࠶࠹ࠖࡦࠣߩ⸃ᨆ߆ࠄ᷹ⷰὐઃㄭߩᐢၞᔕജ႐ߩᣇะࠍផ
ቯߔࠆ⎇ⓥ߇ᄙߊߥߐࠇߡ߈ߚ㧔଀߃߫‫ޔ‬Crampin‫ޔ‬1987;࿑ ‫⸃ޓ‬ᨆߦ૶↪ߒߚ᷹ⷰὐಽᏓ㧔ਃⷺ㧕ߣ‫ޔ‬㧔ᐔᚑ 㧕ᐕ߆ࠄ 㧔ᐔᚑ 㧕ᐕ߹ߢߦ᳿ቯߐࠇߚ㔡ḮಽᏓ㧔⊕ਣ㧕‫ߪ✢ߩ࡯࡟ࠣޕ‬ᢿጀࠍ␜ߔ‫ޕ‬

Kaneshima‫ޔ‬1990㧕‫৻ޕ‬ᣇߢ‫ޔ‬ᢿጀ⎕⎈Ꮺߩਛࠍㅢߞߡߊࠆ࿾㔡ᵄߪ‫ޔ‬ᐢၞᔕജ႐ߩᣇะࠃࠅ߽߻ߒࠈᢿጀߩ⿛ะ␹ᄹᎹ⋵᷷ᴰ࿾ቇ⎇ⓥᚲ‫␹ ޥ‬ᄹᎹ⋵ዊ↰ේᏒ౉↢↰ ႎ๔㧘␹ᄹᎹ⋵᷷ᴰ࿾ቇ⎇ⓥᚲႎ๔㧘╙  Ꮞ㧘㧘㧚࿑ ‫ޓ‬5 ᵄࠬࡊ࡝࠶࠹ࠖࡦࠣߩ᭎ᔨ࿑‫࠲࡯ࡔ࡜ࡄߩߟ ޕ‬
㧔.52& ߣ &6㧕߆ࠄ⇣ᣇᕈᇦ⾰ߩᕈ⾰ࠍផቯߔࠆ‫ޕ‬ߦᐔⴕߥ LSPD ࠍᜬߟߎߣ߇ Tadokoro et al.
㧔1999㧕ߥߤ࿑ ‫ޓ‬%TQUU%QTTGNCVKQP ᴺߦࠃࠆ⸃ᨆߩ଀‫ޕ‬Ꮐਅߦ‫ޔ‬ᵄᒻߩ࿁ォⷺߣᤨ㑆Ꮕߦࠃࠆ⋧㑐ଥᢙߩᄌൻࠍ␜ߔ‫ߞ߽ޕ‬ߣ߽⋧㑐߇㜞޿࿁ォⷺ  㩩‫ᤨޔ‬㑆Ꮕ  ⑽㧔⊕⍫ශߩ૏⟎㧕ߢධർ෸߮᧲⷏ᚑಽߩᵄᒻࠍߕࠄߒߡ㊀ߨߚ߽ߩ߇‫ޔ‬ਛᲑߦ␜ߔᵄᒻߢ޽ࠆ‫ޕ‬ᵄᒻ߇⦟ߊૃߡ߅ࠅ‫ޔ‬Ꮐߦ␜ߒߚ☸ሶ゠〔߇⋥✢⁁ߦߥߞߡ޿ࠆߎߣ߇ಽ߆ࠆ‫ޕ‬ฝਅߦ‫ޔ‬㔡Ḯߣ᷹ⷰὐߩ૏⟎㑐ଥ෸߮⊒㔡ᤨࠍ␜ߔ‫ޕ‬ߦࠃߞߡ␜ߐࠇߡ޿ࠆ‫ޕ‬࠺࡯࠲ߣ⸃ᨆᚻᴺ‫⸃ޓ‬ᨆߦߪ᷷ᴰ࿾ቇ⎇ⓥᚲ߇ዷ㐿ߔࠆ࿾㔡᷹ⷰ✂㧔࿑ 1㧕ߢ᷹ⷰߐࠇߚ࿾㔡ᵄᒻߦ 2-8Hz ߩࡃࡦ࠼ࡄࠬࡈࠖ࡞࠲࡯ࠍ߆ߌߚ߽ߩࠍ૶↪ߒߚ‫⎇ᧄޕ‬ⓥߢߪ 1997
㧔ᐔᚑ 9㧕ᐕ߆ࠄ 2005㧔ᐔᚑ 17㧕ᐕ߹ߢߦᒰೋߩ᷹ⷰ✂ߢ㔡Ḯ᳿ቯߒߚ࿾㔡ߩ߁ߜ‫ࡦࡇ࡝ࠖࡈޔ‬ᶏࡊ࡟࡯࠻߅ࠃ߮࿾Ზౝߢߩ⇣ᣇᕈಽᏓࠍផቯߔࠆߚ߼‫ޔ‬ᄥᐔᵗࡊ࡟࡯࠻ߩ࿾㔡߅ࠃ߮▫ᩮἫጊߩἫጊᕈߩ࿾㔡ࠍ㒰ߊᷓߐ 10km ߆ࠄ 50km ߩ߽ߩࠍㆬᛯߒߚ‫ߚ߹ޕ‬ᄌ឵ᵄߦࠃࠆ૏⋧ߩᄌൻࠍㆱߌࠆߚ߼ߦ‫ⷰޔ‬᷹ὐ߳ߩᵄ✢ߩ౉኿ⷺ߇ 35 ᐲએਅߩ࿾㔡ߩߺࠍ૶↪ߒߚ‫౉ޕ‬኿ⷺߣ࿾㔡ᵄߩવ᠞〒㔌ߪ‫ޔ‬᷷࿾⎇ߩ࡞࡯࠹ࠖࡦᬺോߢ૶↪ߒߡ޿ࠆ 1 ᰴరㅦᐲ᭴ㅧ㧔ᐔ⾐‫ޔ‬1987㧕
ࠍ↪޿ߡ⸘▚ߒߚ‫ޓޕ‬‫ޓ‬S ᵄࠬࡊ࡝࠶࠹ࠖࡦࠣߩࡄ࡜ࡔ࡯࠲㧔LSPD‫ޔ‬DT㧕ߪ
Cross-correlation ᴺ㧔଀߃߫‫ޔ‬ShinandMeyer‫ޔ‬1990㧕ࠍ↪
޿ߡផቯߒߚ‫ޕ‬࿑ 3 ߦࠬࡊ࡝࠶࠹ࠖࡦࠣࠍ␜ߔᵄᒻߩ଀
ߣ‫ޔ‬Cross-correlation ᴺߦࠃࠆࡄ࡜ࡔ࡯࠲ផቯߩ଀ࠍ␜
ߔ‫ޕ‬࿑ߩᏀਅߦ‫ޔ‬࿁ォⷺߣᤨ㑆ߕࠇߦኻߔࠆ᳓ᐔ 2 ᚑಽߩᵄᒻߩ⋧㑐୯ࠍ␜ߔ‫❑ޕ‬ゲ߇ 151‫ޔ‬ᮮゲ߇ -0.07 ߩ૏⟎ߢ⋧㑐ଥᢙ߇ᦨᄢߣߥࠅ‫ޔ‬᳓ᐔᚑಽߩᵄᒻࠍ N151E ߦ࿑ ‫⿷ޓ‬ᨩᐔ㊁๟ㄝߩ᷹ⷰὐߢᓧࠄࠇߚ .52&‫ޕ‬࿑ߩฝਅߦ᫜↰㧔㧕ߦࠃߞߡᓸዊ࿾㔡ߩࡔࠞ࠾࠭ࡓ߆ࠄផቯ
ߐࠇߚ 2 ゲߩᣇะࠍ␜ߔ‫ޕ‬.52& ߪ߶߷ 2 ゲߩಽᏓߩ▸࿐ౝߦ෼߹ࠆ‫ޕ‬▫ᩮ๟ㄝߩ྾ⷺߪ࿑  ߩ▸࿐ࠍ␜ߔ‫ޕ‬࿑ ‫ޓ‬-+0‫ޔ‬-<;‫ޔ‬60/ ߢ᷹ⷰߐࠇߚ .52& ߣ &6 ߩ㔡Ḯᷓߐߣ౉኿ᣇะߦኻߔࠆࡊࡠ࠶࠻‫ޕ‬ὐ✢ߪ .52& ߇ 0 㩩 ' ߆ࠄ 0 㩩 'ߩ▸࿐ࠍ␜ߔ‫& ߚ߹ޕ‬6 ߩᄢ߈ߐߪ‫ޔ‬ᵄߩવ᠞〒㔌ߢᱜⷙൻߒ  ߆ࠄ  ߩ▸࿐ߦ౉ࠆࠃ߁ଥᢙࠍដߌߚ߽ߩࠍࠣ࡜࠺࡯࡚ࠪ
ࡦߢ⴫ߒߡ޿ࠆ‫߇⦡ޕ‬Ớ޿߶ߤන૏〒㔌ࠍવ᠞ߔࠆ㑆ߦߕࠇࠆᤨ㑆Ꮕ߇ᄢ߈޿‫ޕ‬࿁ォߐߖ‫ޔ‬0.07 ⑽ߛߌߕࠄߔߣ‫ߩߟߚ߰ޔ‬ᵄᒻ߇㕖Ᏹߦߦኻߒ‫ⷰ࡞࡯ࡎࠕࡏޔ‬᷹ὐߢ޽ࠆ YDR ߢߪ᣿⍎ߦ S ᵄࠃߊૃߡ޿ࠆߎߣࠍ␜ߒߡ޿ࠆ‫ޕ‬࿑ߩਛᲑߦ‫ޔ‬᳓ᐔಽߩ஍ะ߇᷹ⷰߐࠇ‫ޔ‬ർ⷏̅ධ᧲ᣇะ
㧔N120°E ߆ࠄ N170°E㧕ᚑಽߩᵄᒻࠍ࿁ォߐߖߡᤨ㑆ࠍߕࠄߒߡ㊀ߨߚ߽ߩࠍ␜

ߦ LSPD ߇ථ⿧ߔࠆߎߣ߇ಽ߆ߞߚ‫ޕ‬OMZ ߦߟ޿ߡ߽ߔ‫⋧ޕ‬㑐ଥᢙ߇ 0.8 એ਄ߩ࿾㔡ߦߟ޿ߡ‫ޔ‬S ᵄࠬࡊ࡝࠶߿߿߫ࠄߟ߈ߪᄢ߈޿߽ߩߩห᭽ߩ௑ะ߇⷗ࠄࠇࠆ‫ߎޕ‬࠹ࠖࡦࠣߩࡄ࡜ࡔ࡯࠲ߣߒߡណ↪ߒߚ‫ޕ‬ࠇࠄߪ‫ޔ‬๟ㄝߩᓸዊ࿾㔡ࡔࠞ࠾࠭ࡓ⸃ߩ P ゲᣇ૏㧔᫜↰‫ޔ‬2004㧧ⴕ┻߶߆‫ޔ‬2006㧕ߣ⺞๺⊛ߢ޽ࠅ‫ޔ‬๟ㄝߩᐢၞᔕജ⸃ᨆ⚿ᨐ႐ࠍ෻ᤋߒߡ޿ࠆߣ⠨߃ࠄࠇࠆ‫ޕ‬IWK‫ޔ‬HIN ߪߘࠇߙࠇ

.52& ߩⓨ㑆⊛ᄌൻධർᣇะ‫ޔ‬ർ⷏̅ධ᧲ᣇะߦ㧿ᵄೋേߩ஍ะ߇⷗ࠄࠇࠆ‫ ޓ‬࿑ 4 ߦ‫ ⿷ ޔ‬ᨩ ᐔ ㊁ ๟ ㄝ ߦ ޽ ࠆ OMZ‫ޔ‬YDR‫ޔ‬IWK‫ޔ‬߇‫ޔ‬࿾㔡ᢙ߇ઁߣᲧセߒߡዋߥ޿ߚ߼߆᣿⍎ߥ௑ะߪ⷗

HIN ߩ ฦ ⷰ ᷹ ὐ ߢ ߩ 㧿 ᵄ ೋ േ ߩ ஍ ะ ᣇ ะ ࠍ ␜ ߔ‫ޕ‬߃ߥ޿‫ޕ‬

Cross-correlation ᴺߦࠃߞߡᓧࠄࠇߚ஍ะᣇะߦᵄߩવ

‫ޓ‬TNM‫ޔ‬KZY ߩ 2 ὐߢߪ‫ޔ‬ർ⷏̅ධ᧲ᣇะ
㧔N120°E ߆ࠄ᠞〒㔌ߦࠃߞߡⷙᩰൻߒߚᤨ㑆Ꮕ
㧔DT㧕ࠍ㊀ߺઃߌߒߚ‫ޕ‬N150°E㧕ߦ㧿ᵄೋേߩ஍ะ߇᷹ⷰߐࠇߚ
㧔࿑ 4㧕‫ߩߎޕ‬ᣇ

ߐࠄߦ 0 ߆ࠄ 1 ߩ▸࿐ߦ౉ࠆࠃ߁ߦㆡᒰߥଥᢙࠍ߆ߌߡ

૏ߪ๟ㄝߩᓸዊ࿾㔡ࡔࠞ࠾࠭ࡓ⸃ߩ P ゲߦㄭߊ‫ޔ‬ᐢၞᔕࡠ࡯࠭࠳ࠗࠕࠣ࡜ࡓߢ␜ߒߚ‫ޕ‬એᓟߩ LSPD ࠍ␜ߔ࿑ߪജ႐ߩᓇ㗀ߣ߽⠨߃ࠄࠇࠆ‫ޔߒ߆ߒޕ‬DT ߩ౉኿ᣇ૏ߦోߡห᭽ߩ⴫␜ߢ޽ࠆ‫ޕ‬ኻߔࠆಽᏓࠍ⷗ࠆߣ㧔࿑ 5㧕‫ޔ‬DT ߩᄢ߈ߐ߇౉኿ᣇะߦ‫ޓ‬IWK ߪߏߊㄭறߦ᧲ฬ㜞ㅦ㆏〝߇⿛ߞߡ߅ࠅ߹ߚࠃߞߡ߆ߥࠅ⇣ߥࠆߎߣ߆ࠄ‫ޔ‬࿾㔡ᵄߩવ᠞⚻〝਄ߦ๟HIN‫ޔ‬OMZ ߪ࿾⴫ߦ࠮ࡦࠨ࡯߇⟎޿ߡ޽ࠆߚ߼‫ޔ‬ᵄᒻߩ࿐ߣ⇣ߥࠆዪᚲ⊛ߥ⇣ᣇᕈ᭴ㅧ߇ሽ࿷ߔࠆน⢻ᕈ߇ᒝ޿ࡁࠗ࠭࡟ࡌ࡞߇㜞ߊ߿߿ LSPD ߦᢔࠄ߫ࠅ߇⷗ࠄࠇࠆߩߣ⠨߃ࠄࠇࠆ‫ޔ߫߃଀ޕ‬TNM ߢߪᣇ૏ⷺ N320°E ߆ࠄ⊒࿾㔡߇⊒↢ߒ‫ޔ‬ᶏᛮ 0km ઃㄭߦ⿛ะ N100°E ߅ࠃ߮N140°E ߩ㐿ญࠢ࡜࠶ࠢߩሽ࿷߇␜ໂߐࠇߡ޿ࠆ㧔ઍ↰‫ޔ‬⑳ା㧕‫⊒⟲ߩߎޕ‬࿾㔡೨ᓟߢථ⿧ߔࠆ LSPD ߇ߘࠇ߹ߢߣᲧߴߡᄢ߈ߊ߆ࠊࠆߎߣ߆ࠄ‫⊒⟲ޔ‬࿾㔡ߦ઻߁ࠢ࡜࠶ࠢߩᓇ㗀ࠍᒝߊฃߌߡ޿ࠆߣ⠨߃ࠄࠇࠆ‫ޔߪߣߎߩߎޕ‬2000 ᐕ෸߮ 2001 ᐕߦߟ޿ߡ㔡Ḯߩᷓߐߣ 2 ߟߩ S ᵄߩવ᠞〒㔌޽ߚࠅߩᤨ㑆Ꮕ߇‫ޔ‬ᵻ޿࿾㔡߶ߤᄢ߈޿㧔࿑ 8㧕ߣ߽⺞๺⊛ߢ޽ࠆ‫ ߩߎޕ‬2 ߟߩ᷹ⷰὐߩ⹦ߒ޿ᤨ㑆ᄌൻߦߟ޿ߡߪᓟㅀߔࠆ‫ޕ‬KZR ߢ߽ห᭽ߦ⷏ർ⷏ߦᒝ޿஍ะ߇᷹ⷰߐࠇࠆ߇‫ⷰޔ‬᷹ᦼ㑆ߣ౉኿ᣇ૏ߦ㑐ࠊࠄߕ
N110°E ߩ LSPD ߇᷹ⷰߐࠇࠆߎߣ߆ࠄ‫ޔ‬KZR ㄭறߦ㧿ᵄࠍ⷏ർ⷏ߦ஍ะߐߖࠆ⇣ᣇᕈ᭴ㅧ߇ሽ࿷ߔࠆߣ⠨߃ࠄ࿑ ‫ޓ‬-+0‫ޔ‬60/‫ޔ‬-<; ߢ᷹ⷰߐࠇߚ࿾㔡ᵄᒻߩ߁ߜ‫ޔ‬.52&
߇ 0 㩩 ' ߆ࠄ 0 㩩 ' ߩ▸࿐ߦ౉ࠆ㔡Ḯߩᣇ૏ࠍ࿾࿑਄ߦὐ✢ߢ␜ߔ‫ⷰ ޕ‬᷹ὐߩ⚿ᨐ߆ࠄ⇣ᣇᕈ߇ᒝ޿ߣ್ᢿߐࠇࠆ႐ᚲࠍᢳ✢ߢ␜ߒߚ‫ޕ‬

N10°E‫ޔ‬KZY ߢߪ N20°E ߆ࠄ N60°E ߩ▸࿐߆ࠄ᷹ⷰὐߦ
౉኿ߒߡߊࠆ S ᵄ߇ N140°E ߩᣇะߦᒝߊ஍ะߔࠆ‫߹ޕ‬ߚ‫ޔ‬20 ࠠࡠࠃࠅ߽ᵻ޿࿾㔡߆ࠄߩ 2 ߟߩ S ᵄߩන૏〒㔌޽ߚࠅߩᤨ㑆Ꮕ߇ᄢ߈޿ߎߣ߆ࠄ‫⇣ߩߎޔ‬ᣇᕈߩේ࿃ߪߎࠇࠄߩ㔡Ḯࠃࠅᵻ޿ㇱಽߦ㓸ਛߒߡ޿ࠆߎߣ߇ಽ߆ࠆ‫ޕ‬LSPD ߇ N130°E ߆ࠄ N160°E ߩ▸࿐ߦ౉ࠆ㔡Ḯߩᣇ૏ࠍ TNM‫ޔ‬KIN‫ޔ‬KZY ߦߟ޿ߡ࿾࿑਄ߦ␜ߔߣ‫ߩߎޔ‬஍ะ⇣Ᏹߩේ࿃ߪ࿑ 6 ߩᢳ✢ߢ␜ߒߚઃㄭߦሽ࿷ߔࠆߣ
ផቯߐࠇࠆ‫ޕ‬‫▫ޓ‬ᩮἫጊਛᄩㇱߦ૏⟎ߔࠆ OWD‫ޔ‬KOM‫ޔ‬KZR ߢߪ‫ޔ‬
TNM ߥߤߢ᷹ⷰߐࠇߚ LSPD ࠃࠅ߽ߐࠄߦ᧲⷏ߦㄭ
޿ N110°E ઃㄭ߇ථ⿧ߔࠆ LPSD ߇᷹ⷰߐࠇߚ㧔࿑㧣㧕‫ޕ‬
OWD‫ޔ‬KOM ߩ⋥ਅߢߪ 2001（ᐔᚑ 13㧕ᐕߦᄢⷙᮨߥ⟲࿑ ‫▫ޓ‬ᩮἫጊ๟ㄝߩ᷹ⷰὐߢᓧࠄࠇߚ .52&‫ޕ‬ฝਅߦ᫜↰㧔㧕ߦࠃࠆ‫ޔ‬ᓸዊ࿾㔡ߩ⸃ᨆ߆ࠄᓧࠄࠇߚ 2 ゲߩႎ๔ࠍ␜ߔ‫ޕ‬࿑ ‫ޓ‬-1/ ߣ 19& ߩ  ᐕ෸߮  ᐕߩ᷹ⷰ࠺࡯࠲߆ࠄ
ᓧࠄࠇߚ .52& ߣන૏〒㔌޽ߚࠅߩᤨ㑆Ꮕ‫ޕ‬19& ߢߪ0°'‫ޔ‬-1/ ߢߪ 0°' ߩ .52& ߇ථ⿧ߔࠆ߇‫ߕ޿ޔ‬ࠇߩ᷹ⷰὐߢ߽ᵻ޿࿾㔡߶ߤන૏〒㔌޽ߚࠅߩᤨ㑆Ꮕ߇ᄢ߈޿‫ޕ‬࿑㧥19& ߢߩ .52& ߩᤨ㑆ᄌൻ‫ ޕ‬ᐕઍߪർ᧲  ධ⷏ᣇะ߇ථ⿧ߔࠆߩߦኻߒ‫ ޔ‬ᐕએ㒠ߪ⷏ർ⷏  ᧲ධ᧲ᣇะ߇ථ⿧ߔࠆ‫ޕ‬ὐ✢ߪઍ↰ ⑳ା ߦࠃࠆ㐿ญࠢ࡜࠶ࠢߩ⿛ะ‫ޕ‬࿑ ‫ޓ‬-1/ ߢߩ .52& ߩᤨ㑆ᄌൻ‫ ޕ‬ᐕ߆ࠄ  ᐕߦ߆ߌߡർ⷏  ධ᧲ᣇะߩ .52& ߇ථ⿧ߔࠆ‫ޕ‬ὐ✢ߪઍ↰㐿ญࠢ࡜࠶ࠢߩ⿛ะ‫ޕ‬⑳ାߦࠃࠆࠇࠆ‫ޕ‬SSN ߦߟ޿ߡߪ LSPD ߩ߫ࠄߟ߈߇ᄢ߈޿ߩߢᧄ

ߚ߼ߦ KZY ߦ೔㆐ߔࠆᵄ✢߇ߎߩࠢ࡜࠶ࠢߩ޽ࠆ㗔ၞႎ๔ߢߪ⹦ߒߊߪㅀߴߥ޿‫ޕ‬ࠍㅢㆊߒߥ޿ߚ߼ߢ޽ࠆߣ⠨߃ࠄࠇࠆ‫ޕ‬‫ޓ‬KOM ߦߟ޿ߡ߽ OWD ߣห᭽ߦ 2000 ᐔᚑ 12㧕ᐕ߆ࠄ.52& ߩᤨ㑆⊛ᄌൻ2001㧔ᐔᚑ 13㧕ᐕߦ߆ߌߡߩᦼ㑆ࠍߪߐࠎߢ‫ޔ‬LSPD ߇ᄢ‫ޓ‬OWD ߣ KOM ߢߪ᣿⍎ߥ LSPD ߩᤨ㑆ᄌൻ߇᷹ⷰߐ

߈ߊᄌൻߒߡ޿ࠆߎߣ߇ࠊ߆ࠆ‫ ߪࠇߎޕ‬2001 ᐔᚑ 13㧕ࠇߚ‫ޕ‬OWD ߦߟ޿ߡߪ‫ޔ‬࿑㧣ߦ޽ࠆࠃ߁ߦ᷹ⷰᦼ㑆ోᐕߩ▫ᩮ⟲⊒࿾㔡ߩ㓙ߦ௑ᢳ⸘ߩ⸥㍳߆ࠄផቯߐࠇߚ‫ޔ‬

૕ߢߪ N110°E ߩ LSPD ߇ථ⿧ߒߡ޿ࠆ߇‫ޔ‬1997㧔ᐔᚑ 9㧕㚤ࠤጪ⋥ਅߩ㐿ญࠢ࡜࠶ࠢߩᣇะ
㧔N140°E㧕ߣࠃߊ৻⥌ᐕ߆ࠄ 1999 ᐔᚑ 11㧕ᐕ‫ޔ‬2000 ᐔᚑ 12㧕ᐕ߆ࠄ 2001 ᐔߔࠆ㧔࿑ 10㧕‫ޕ‬ᚑ 13 ᐕ߅ࠃ߮ 2002 ᐔᚑ 13）ᐕએ㒠ߦಽߌߡ LSPD ࠍࡊࡠ࠶࠻ߔࠆߣ‫ޔ‬᣿ࠄ߆ߦ 2000 ᐔᚑ 12㧕
ᐕ߆ࠄ 2001㧔ᐔ߹ߣ߼ᚑ 13㧕ᐕએ㒠ߦ LSPD ߇ᄌൻߔࠆߎߣ߇ಽ߆ࠆ㧔࿑ 9㧕‫ޕ‬‫⿷ޓ‬ᨩᐔ㊁๟ㄝㇱߩ᷹ⷰὐ‫ࠇߐ⟎⸳ߦ࡞࡯ࡎࠕࡏߦ․ޔ‬ߎߩᦼ㑆ߦߪ‫ޔ‬2001 ᐔᚑ 13㧕ᐕߦ▫ᩮߢ⟲⊒࿾㔡߇⊒ߚ YDR ߣࡁࠗ࠭߇ዋߥ޿ OWD ߢߪ㔡Ḯߩ૏⟎ߦነࠄ↢ߒߡ߅ࠅ‫ߩߘޔ‬㓙ߦ௑ᢳ⸘ߢ⸥㍳ߐࠇߚ࿾Ზᄌേ߆ࠄ‫ޔ‬ߕർ⷏ - ධ᧲ᣇะߦ㧿ᵄೋേߩ஍ะ߇᷹ⷰߐࠇ‫ޔ‬ㆊ෰ߩਛᄩἫญਐߩ⋥ਅ 2km
㧔ᶏᛮ㧜km㧕⒟ᐲߩߣߎࠈߦ N100°E⎇ⓥߢᓧࠄࠇߚᐢၞᔕജ႐ߩᣇะߣࠃ޿৻⥌ࠍ␜ߒߚ‫ޕ‬ߩ⿛ะࠍ߽ߟ㐿ญࠢ࡜࠶ࠢߩሽ࿷߇ផቯߐࠇߡ޿ࠆ‫ޕ‬2000‫▫ޓ‬ᩮἫጊౝߩ᷹ⷰὐߢߪో૕ߣߒߡᵻ޿࿾㔡߆ࠄߩ㧿

ᐕ߆ࠄ 2001 ᐕߦ߆ߌߡߩ LSPD ߩᄌൻߪ‫࠶࡜ࠢߩߎޔ‬ᵄ߇᧲⷏ߦㄭߊᒝ޿஍ะࠍ␜ߔ‫ޔߜ߁ߩࠄࠇߎޕ‬OWD‫ޔ‬ࠢߩᓇ㗀ࠍᒝߊฃߌߡ޿ࠆߣ⠨߃ࠄࠇࠆ‫ޕ‬ዊႦጊ⋥਄ߩ

KOM ߢߪ 2001 ᐔᚑ 13㧕ᐕߩ⟲⊒࿾㔡ߩ೨ᓟߢ LSPD ߦKZY ߢߎߩᄌൻ߇⷗߃ߥ޿ߩߪ‫⋥ޔ‬ਅߦ࿾㔡߇ዋߥ޿ᄌൻ߇⷗ࠄࠇ‫⊒⟲ޔ‬࿾㔡ߦ㑐ㅪߒߚࠢ࡜࠶ࠢߩ⿛ะࠍ෻ᤋߒߚߣ⠨߃ࠄࠇࠆ‫ޕ‬2002 ᐔᚑ 14㧕ᐕએ㒠ߩ LSPD ߩෳ⠨ᢥ₂ಽᏓࠍߺࠆߣ‫ޔ‬KOM ߪ߶߷⟲⊒࿾㔡એ೨ߣห᭽ߩࡄ࠲࡯

Crampin S.（1987）Shear-wave splitting above smallࡦࠍ␜ߔߩߦኻߒ‫ޔ‬OWD ߦߟ޿ߡߪ⟲⊒࿾㔡ߩ೨ᓟߦearthquakes in the Kinki district of Japan, Phys. Earth⷗ࠄࠇࠆ N110 㩩 E ߩ LSPD ߇ 2002 ᐔᚑ 14㧕ᐕએ㒠߽ᲧPlanet. Interiors, , 45-58.

セ⊛ߪߞ߈ࠅߣߒߡ޿ࠆ‫▫ޔߪߣߎߩߎޕ‬ᩮἫጊߩ࿾ਅઍ↰‫ޓ‬ካ࡮᫜↰ବᡴ࡮દ᧲‫ޓ‬ඳ   㧔ᐔᚑ 㧕ߦ߅޿ߡ‫ ߦߛᧂޔ‬N110 㩩 E ߩ⿛ะࠍᜬߟࠢ࡜࠶ࠢ߇㐽ᐕ▫ᩮ⟲⊒࿾㔡ᵴേߦ㑐ㅪߒߚ࿾Ზ௑ᢳᄌേ  ᷷࿾ߓߡ޿ߥ޿ߎߣࠍ␜ໂߒߡ޿ࠆ‫ޕ‬⎇ႎ๔ ‫ޓ‬2001 ᐔᚑ 13㧕ᐕߩ⟲⊒࿾㔡ߢߪ▫ᩮἫጊౝߦ⸳⟎ߐࠇߚࡏࠕࡎ࡯࡞௑ᢳ⸘ߦࠃߞߡ‫⊒⟲ޔ‬࿾㔡ߩ⿠ߎࠆ⚂ᐔ⾐჻㇢   ▫ᩮἫጊߣ▫ᩮ๟ㄝᶏၞߩ࿾㔡ᵴേ‫ޔ‬᷷⎇ႎ๔   R

3 ㅳ㑆೨߆ࠄ࿾Ზᄌേߩᄌൻ߇᷹ⷰߐࠇߡ޿ࠆ
㧔ઍ↰߶Hiramatsu Y.（2005）Seismological evidence on characteristic߆‫ޔ‬2002㧕‫⎇ᧄޕ‬ⓥߩኻ⽎࿾ၞߢߪἫጊߦኻߒߡ࿾㔡ಽtime of crack healing in the shallow crust, Gephys. Res.

Ꮣ߇஍ߞߡ߅ࠅ࿾㔡ᢙ߽ዋߥ޿ߚ߼ߦᤨ㑆⊛ⓨ㑆⊛ߦဋ

Lett., , L09304, doi10.1029/2005GL022657.

⾰ߥ࠺࡯࠲߇ᓧࠆߎߣ߇㔍ߒ޿߇‫ޔ‬ⓨ㑆⊛ߦኒߥ᷹ⷰ✂ߦࠃߞߡᧄ⎇ⓥߩࠃ߁ߥ㧿ᵄࠬࡊ࡝࠶࠹ࠖࡦࠣߩᤨ㑆ᄌ⍹ᯅసᒾ  ̌␹ᄹᎹ⋵⷏ㇱ࿾㔡̍ߣ࿾㔡੍⍮ +⑼ቇ ൻ߇ᝒ߃ࠄࠇࠇ߫‫߇⟎⸳ޔ‬Ყセ⊛ኈᤃߥ࿾㔡⸘ߩ⸥㍳ߦ

Kaneshima S.（1990）Origin of crustal anisotropy: ShearࠃߞߡἫጊᵴേߩࡕ࠾࠲࡝ࡦࠣ߇ߢ߈ࠆน⢻ᕈ߇޽ࠆ‫ޕ‬wave splitting studies in Japan., J. Geophys. Res.,‫ޓ‬TNM‫ޔ‬KZY ߢߪ▫ᩮἫጊౝߩ᷹ⷰὐߣ⇣ߥࠅർ⷏ - ධ

$,11121-11133.

᧲ᣇะߦᒝ޿஍ะ߇᷹ⷰߐࠇߚ‫ޕ‬TNM‫ޔ‬KZY‫ޔ‬KIN ߦߟ޿ߡർ⷏ - ධ᧲ߦ஍ะࠍ␜ߔ㧿ᵄߩ౉኿ᣇะ߆ࠄᵄ✢߇ਛ᧛৻᣿㧔㧕ᐢၞᔕജ႐ࠍ෻ᤋߒߚἫጊ૕ߩ᭴ㅧ Ἣጊ ㊀ߥࠆㇱಽࠍផቯߔࠆߣ‫⿷ޔ‬ᨩᐔ㊁ߩർ⷏┵ߦዪᚲ⊛ߦ

Shin, X. R. and Meyer R. P.㧔1990㧕Observation of shear⇣ᣇᕈߩᒝ޿㗔ၞ߇ሽ࿷ߔࠆߣ⠨߃ࠄࠇࠆ‫⇣ߩࠄࠇߎޕ‬wave splitting from natural events: South Moat of Longᣇᕈߩේ࿃ߦߟ޿ߡ 1 ࡑࠣࡑߥߤߩ⽾౉ߦࠃࠆ⚿᥏ߩValley Caldera, California, June 29 to august 12, 1982.

ㆬᛯ㈩ะ‫ ޔ‬2 ᔕജߩ㓸ਛߦࠃࠅ๟ㄝࠃࠅ߽࿾Ზౝߩࠢ

Journal of Geophysical Research, $, 11179-1195.

࡜࠶ࠢኒᐲ߇ᄢ߈޿‫߇ߤߥޔ‬⠨߃ࠄࠇࠆ‫ࠍࠇߎޕ‬ᬌ⸽ߔ

Tadokoro K., Ando M. and Umeda Y.（1999）S wave splittingࠆߚ߼ߦߪ‫⸃ߩߤߥࠣࡦ࡝࡯ࡏޔ‬ᨆ⚿ᨐߣᲧセߔࠆ߆‫ޔ‬in the aftershock region of the 1999 Hyo-go ken Nanbu޽ࠆ޿ߪ GPS ߥߤߩ⥃ᤨ᷹ⷰࠍⴕߞߡᱡ႐ߩ᷹ⷰࠍⴕ

earthquake, $, 981-991.

߁ߎߣ߇ᔅⷐߢ޽ࠆ‫ޕ‬S ᵄࠬࡊ࡝࠶࠹ࠖࡦࠣߩࡄ࡜ࡔ࡯᫜↰ବᡴ㧔㧕␹ᄹᎹ⋵⷏ㇱ࿾ၞߦ߅ߌࠆ㔡Ḯߥࠄ߮࠲ߪᱡㅦᐲߦᢅᗵߢ޽ࠆน⢻ᕈ߇ᜰ៰ߐࠇߡ޿ࠆߎߣ߆ߦࡔࠞ࠾࠭ࡓಽᏓߣ̌␹ᄹᎹ⋵⷏ㇱ࿾㔡̍ᗐቯᢿጀߣߩࠄ㧔଀߃߫ Hiramatsu2005㧕‫੹ޔ‬࿁⇣ᣇᕈ߇ᒝ޿ߣផቯ㑐ଥ ᣣᧄ࿾㔡ቇળ⑺ቄᄢળ੍Ⓜ㓸 2ߐࠇߚ࿾ၞߢߪ๟ㄝࠃࠅ߽ᱡㅦᐲ߇ㅦ޿น⢻ᕈ߇޽ࠆ‫ޕ‬

Ukawa M.（1991）Collision and Fan-Shaped Compressionalዊ↰ේ๟ㄝߪ⚂ 73 ᐕߏߣߦ࿾㔡ߩⵍኂࠍฃߌߡ߅ࠅ‫ޔ‬Stress Pattern in the Izu Block at the Northern Edge of the߹ߚߘߩ㔡Ḯᢿጀߣߒߡ⷏⋧ᮨḧᢿⵚ߇ሽ࿷ߔࠆߣߐࠇ

Philippine Sea Plate, Journal of Geophysical Research, $,ࠆ࿾ၞ㧔⍹ᯅ‫ޔ‬1985㧕ߢ߽޽ࠆߎߣ߆ࠄ‫ޔ‬ᒝ޿⇣ᣇᕈߩේ713-728.

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Wessel, P. and Smith W.（1995）New version of the genericⴕ߁਄ߢ߽㊀ⷐߢ޽ࠆ‫ᤨߩࠣࡦࠖ࠹࠶࡝ࡊࠬޕ‬㑆Ꮕ DT

mapping tools, EOS. Trans. Am. Geophys. Un., , 329.

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