Lunar Multiring Basinsandthe Cratering ProcessⓎ⾲ෆᐜ⫼ᬒෆ㒊ᵓ㐀᥎ᐃ 䞉 Excavation cavity 䛾᚟ඖ– 㔜ຊሙ䝕䞊䝍䜢⏝䛔䛯䜲䞁䝞䞊䝆䝵䞁䛻䜘䜛ෆ㒊ᵓ㐀᥎ᐃ
– Excavation cavity ᚟ඖWieczorek, M., and R. J. Phillips (1999)
Icarus 139, 246-259
㆟ㄽ– Excavation cavity 䛾῝䛥䞉┤ᚄẚ– 䝸䝮௜㏆䛾䜲䝆䜵䜽䝍ཌ– 䜰䜲䝋䝇䝍䝅䞊䛛䜙䛾䝈䝺э ྛ┅ᆅ䛷ィ⟬䞉ẚ㍑䛧䚸ᙧᡂ䝯䜹䝙䝈䝮䜢㆟ㄽᢸᙜ䠖 㙊⏣ಇ୍ 䠄ᮾ኱䞉ᮡ⏣◊M2䠅⾪✺ຮᙉ఍
2009.5.26

Image credit: NASA/JPLⓎ⾲ෆᐜ⾪✺䜽䝺䞊䝍䞊⫼ᬒ– 䜽䝺䞊䝍䞊◊✲– ከ㔜䝸䞁䜾┅ᆅ– ෆ㒊ᵓ㐀䛛䜙䛾䜰䝥䝻䞊䝏– ◊✲┠ⓗ㝹▼䞉ᙟᫍ䛺䛹䛾⾪✺⑞– ᅛయᝨᫍ䛻୍⯡ⓗ䛺ᆅᙧෆ㒊ᵓ㐀䜢▱䜛ᡭ᥃䛛䜚¾ ᥀๐䛥䜜䜛≀㉁䛾㔞䛿䠛ෆ㒊ᵓ㐀᥎ᐃ 䞉 Excavation cavity 䛾᚟ඖ¾ ᥀๐䛥䜜䜛῝䛥䛿䠛¾ ᧈ䛝ᩓ䜛䜲䝆䜵䜽䝍䛾ཌ䛥䛿䠛䛺䛹䛺䛹…

㆟ㄽ

Excavation cavity 䜢▱䜛ᚲせImage credit: NASA/JPLỈᫍ䛾Caloris┅ᆅ. MESSENGER᧜ീ.
Image credit: NASA/Johns Hopkins Univ. Appl. Phys. Lab./Carnegie Inst. Washington.

䜽䝺䞊䝍䞊䛾ᙧ≧ከ㔜䝸䞁䜾┅ᆅ䜽䝺䞊䝍䞊䝃䜲䝈䛾ቑ኱䛻క䛖ᙧ≧䛾ኚ໬– ༢⣧䜽䝺䞊䝍䞊 ĺ 」㞧䜽䝺䞊䝍䞊 ĺ ከ㔜䝸䞁䜾䜽䝺䞊䝍䞊– ᐊෆᐇ㦂䛷䛝䛺䛔– ⌮ㄽィ⟬䜒䛹䛣䜎䛷ጇᙜ䠛䠛– ᆅ⌫䛾⾪✺┅ᆅ䛿ಖᏑ≧ែ䛜ᝏ䛔Main rim༢⣧䜽䝺䞊䝍䞊⾪✺┅ᆅ (┤ᚄ > ᩘⓒkm )– 䛚᳐ᙧ㢼໬䞉౵㣗Peak ring」㞧䜽䝺䞊䝍䞊

– ẚ㍑ⓗ䜘䛟ಖᏑ– Main rim 䛾≉ᐃ䛜ᅔ㞴– ୰ኸୣ䜔䝢䞊䜽䝸䞁䜾䛜ぢ䜙䜜䜛– 䝢䞊䜽䝸䞁䜾䛿Main rim 䛾ෆഃ᭶䛾ከ㔜䝸䞁䜾┅ᆅ䝢䞊䜽䝸䞁䜾䜢ᣢ䛴Ỉᫍ䛾」㞧䜽䝺䞊䝍䞊.
MESSENGER᧜ീ.

ከ㔜䝸䞁䜾䜽䝺䞊䝍䞊– Main rim 䛜䛹䜜䛛䜘䛟䜟䛛䜙䛺䛔– ᙧᡂ䝯䜹䝙䝈䝮䛜䜘䛟䜟䛛䜙䛺䛔

Image credit: NASA/Johns Hopkins Univ. Appl. Phys. Lab./Carnegie Inst. Washington.

Ļ᭶䛾Orientale┅ᆅ. Lunar Orbiter IV᧜ീ.
© LPI/Universities Space Research Association䝇䜿䞊䝸䞁䜾๎䛻ᚑ䛖䛻䛧䛶䜒䚸⏬ീゎᯒ䛻䜘䜛

Excavation cavity 䛾᚟ඖ䛿ᅔ㞴ෆ㒊ᵓ㐀䛛䜙䛾䜰䝥䝻䞊䝏◊✲┠ⓗᝨᫍ䞉⾨ᫍ䛾ෆ㒊ᵓ㐀– 㔜ຊሙ 䠄+ᆅᙧ䠅 䝕䞊䝍䛛䜙᥎ᐃ᭶䛾㔜ຊሙ– ┤᥋ィ 䛿⾲ഃ䛾䜏䠄ᙜ᫬䠅– ┅ᆅୗ䛷䛿䝰䝩㠃䛜ୖ᪼᭶䛾ከ㔜䝸䞁䜾 䠄 + SPA 䠅 ┅ᆅ䛻╔┠ᆅᙧ䞉㔜ຊሙ䝕䞊䝍䛛䜙ෆ㒊ᵓ㐀䜢᥎ᐃ䛭䜜䜢⏝䛔䛶᥀๐㔞 䠄 Excavation Cavity 䠅 䛾ぢ✚䜒䜚῝䛥䞉┤ᚄẚ䚸䜲䝆䜵䜽䝍ศᕸ䛺䛹䜢ㄪ䜉䜛Ļ⾪✺䛻䜘䜛ᙳ㡪ᕧ኱ከ㔜䝸䞁䜾┅ᆅ䛾ᙧᡂ䝯䜹䝙䝈䝮䛾⌮ゎ䜈䝬䞁䝖䝹ୖ᪼๓䛾ᆅᙧ䜢᚟ඖэ ᥀๐㔞䛾ぢ✚䜒䜚

Arkani-Hamed (1998)

Crisium┅ᆅ. Appolo VIII ᧜ീ.
Image credit: NASA-JSCⓎ⾲ෆᐜෆ㒊ᵓ㐀䛾᥎ᐃ䠖䝕䞊䝍⫼ᬒᆅᙧ䝕䞊䝍ෆ㒊ᵓ㐀᥎ᐃ 䞉 Excavation cavity 䛾᚟ඖ㔜ຊሙ䝕䞊䝍

– Clementine ᥈ᰝᶵ䛻ᦚ㍕䛥䜜䛯䝺䞊䝄䞊㧗ᗘィ 䠄GLTM-2)– Clementine / Lunar Prospector ᥈ᰝᶵ䛾㏣㊧ (JGL75D)– ෆ㒊ᵓ㐀᥎ᐃ᪉ἲ ⤖ᯝ

GLTM-2

JGL75D

Smith et al. (1997)

Konopliv et al. (1998)– Excavation cavity ᚟ඖ1ᅇ┠䛷኱䜎䛛䛻᚟ඖ䚸2ᅇ┠䛷☜ᐃ᚟ඖ⤖ᯝ㆟ㄽImage credit: NASA/JPLෆ㒊ᵓ㐀䛾᥎ᐃ䠖䝕䞊䝍ෆ㒊ᵓ㐀䛾᥎ᐃ䠖᪉ἲᆅᙧ䝕䞊䝍– Clementine ᥈ᰝᶵ䛻ᦚ㍕䛥䜜䛯䝺䞊䝄䞊㧗ᗘィ 䠄GLTM-2)
䝣䝸䞊䜶䜰␗ᖖ䛛䜙䝤䞊䝀䞊␗ᖖ䛾ィ⟬䠙 ᆅᙧ ( + 䛂ᾏ䛃䛾⋞Ṋᒾ ) 䛾ᙳ㡪䜢ྲྀ䜚㝖䛟㔜ຊሙ䝕䞊䝍㔜ຊ␗ᖖ䠄䝣䝸䞊䜶䜰䠅– Clementine / Lunar Prospector ᥈ᰝᶵ䛾㏣㊧ (JGL75D)ᾏ䛾⋞Ṋᒾୖ㒊ᆅẆୖ㒊ᆅẆ

¾ ୺䛻⾲ഃ䛾┅ᆅୗ㒊ᆅẆୗ㒊ᆅẆ

¾ ⿬ഃ䛿SPA䛾䜏䝬䞁䝖䝹䝬䞁䝖䝹¾ ⥳䠖≉䛻኱䛝䛺3┅ᆅ
¾ 䜸䝺䞁䝆䠖䛭䜜௨እୗ㒊ᆅẆ䛸䝬䞁䝖䝹䜢୍⥴䛻ᣢ䛱ୖ䛢䜛䝬䞁䝖䝹䜢ᣢ䛱ୖ䛢䜛ෆ㒊ᵓ㐀䛾᥎ᐃ䠖᪉ἲෆ㒊ᵓ㐀䛾᥎ᐃ䠖᪉ἲ䝣䝸䞊䜶䜰␗ᖖ䛛䜙䝤䞊䝀䞊␗ᖖ䛾ィ⟬䠙 ᆅᙧ ( + 䛂ᾏ䛃䛾⋞Ṋᒾ ) 䛾ᙳ㡪䜢ྲྀ䜚㝖䛟㔜ຊ␗ᖖ䠄䝣䝸䞊䜶䜰䠅䝣䝸䞊䜶䜰␗ᖖ䛛䜙䝤䞊䝀䞊␗ᖖ䛾ィ⟬ୗ㒊ᆅẆ䛸䝬䞁䝖䝹䜢୍⥴䛻ᣢ䛱ୖ䛢䜛㔜ຊ␗ᖖ䠄䝤䞊䝀䞊䠅䝤䞊䝀䞊␗ᖖ䝤䝀 ␗ᖖィ⟬್ᾏ䛾⋞Ṋᒾୖ㒊ᆅẆୗ㒊ᆅẆୗ㒊ᆅẆ䝬䞁䝖䝹䝬䞁䝖䝹00ୗ㒊ᆅẆ䝬䞁䝖䝹ୗ㒊ᆅẆ䛸䝬䞁䝖䝹䜢୍⥴䛻ᣢ䛱ୖ䛢䜛䝬䞁䝖䝹䜢ᣢ䛱ୖ䛢䜛ෆ㒊ᵓ㐀䛾᥎ᐃ䠖᪉ἲ䝬䞁䝖䝹䜢ᣢ䛱ୖ䛢䜛ෆ㒊ᵓ㐀䛾᥎ᐃ䠖⤖ᯝ 䠄ᑠ䛥䛔┅ᆅ䠅䝣䝸䞊䜶䜰␗ᖖ䛛䜙䝤䞊䝀䞊␗ᖖ䛾ィ⟬ୗ㒊ᆅẆ䛸䝬䞁䝖䝹䜢୍⥴䛻ᣢ䛱ୖ䛢䜛䝬䞁䝖䝹䜢ᣢ䛱ୖ䛢䜛䝤䞊䝀䞊␗ᖖ䝀 ␗ᖖィ⟬್00ෆ㒊ᵓ㐀䛾᥎ᐃ䠖⤖ᯝ 䠄኱䛝䛺┅ᆅ䠅

Excavation cavity 䛾᚟ඖ1ᅇᅇ┠䠖 ᇶ‽ = “Main topographic rim” 䛾2ಸ䛾఩⨨“Main topographic rim”

“Main topographic rim” x 2᥎ᐃ䛥䜜䛯䝰䝩㠃䝸䝞䜴䞁䝗๓䛾䝰䝩㠃

Excavation cavity 䛾᚟ඖ1ᅇ┠䠖 ᇶ‽ = “Main topographic rim” 䛾2ಸ䛾఩⨨

Excavation cavity 䛾᚟ඖ2ᅇ┠䠖 ᇶ‽ = Excavation cavity (ᬻᐃ)䛾4ಸ䛾఩⨨

Excavation cavity 䠄ᬻᐃ䠅
Excavation cavity radii x 4䝸䝞䜴䞁䝗๓䛾䝰䝩㠃䝸䝞䜴䞁䝗๓䛾䝰䝩㠃

Excavation cavity 䛾᚟ඖCavity 䛾᚟ඖ 䠄ᑠ䛥䛔┅ᆅ䠅

2ᅇ┠䠖 ᇶ‽ = Excavation cavity (ᬻᐃ) 䛾4ಸ䛾఩⨨Ex
Excavation
xcavation cavity
Excavation
cavity 䠄☜ᐃ䠅䝸䝞䜴䞁䝗๓䛾䝰䝩㠃

Cavity 䛾᚟ඖ 䠄኱䛝䛔┅ᆅ䠅

Ⓨ⾲ෆᐜ


⫼ᬒ



ෆ㒊ᵓ㐀᥎ᐃ 䞉 Excavation cavity 䛾᚟ඖ㆟ㄽ– Excavation cavity 䛾῝䛥䞉┤ᚄẚ– 䝸䝮௜㏆䛾䜲䝆䜵䜽䝍ཌ– Excavation cavity 䛾༙ᚄ䛸䝸䞁䜾䛾఩⨨㛵ಀ– 䜰䜲䝋䝇䝍䝅䞊䛛䜙䛾䝈䝺

Image credit: NASA/JPLExcavation cavity 䛾῝䛥䞉┤ᚄẚ䝸䝮௜㏆䛾䜲䝆䜵䜽䝍ཌ῝䛥䞉┤ᚄẚ䡚0.1

– ᐇ㦂ⓗ◊✲䛸ᩚྜⓗ– Cavity ┤ᚄ䡚500km 䜘䜚኱䛝䛔䛸ὸ䛟䛺䜛– 䠍ᒙᆅẆ䝰䝕䝹䛷䜒ྠᵝ– ⾪✺๓䛾ᆅẆཌCavity 䛾 2-4 ಸ䛾༙ᚄ䛷䛾ᖹᆒᆅẆཌ– 䛭䜜䜘䜚┒䜚ୖ䛜䛳䛯䛸䛣䜝э 䜲䝆䜵䜽䝍䛾ሁ✚䝇䜿䞊䝸䞁䜾䛛䜙እ䜜䜛ཎᅉ
–(Fig. 4)

Nonproportional scalingᩳ䜑⾪✺–┅ᆅᙧᡂᚋ䛾㛗ᮇ㛫䛻Ώ䜛⢓ᛶ⦆࿴኱䛝䛟䛺䜛䛸䚸ᩳ䜑⾪✺䛾ᙳ㡪䛜ฟ䜔䛩䛔ྍ⬟ᛶ
SPA䛻㛵䛧䛶䛿䛭䜒䛭䜒䝬䞁䝖䝹䛜ぢ䛘䛶䛔䛺䛔䛾䛷䚸䛣䜜䛰䛡䛷ㄝ᫂䛿䛷䛝䛺䛔– ᆅᙧ䛜᭱䜒䛿䛳䛝䜚䛧䛶䛔䜛䝸䞁䜾䜰䜲䝋䝇䝍䝅䞊䛛䜙䛾䝈䝺“Main topographic rim”

“Main topographic rim”ᨭ䛘䛶䛔䜛Ⲵ㔜䛸Cavity┤ᚄ䛿ẚ౛䠛– 䜔䛿䜚኱䛝䛔Serenitatis, Imbrium 䛿㝖እ

Excavation cavity

Excavation cavity 䛾఩⨨Cavity䛷䛷䛿䛺䛟䚸┅ᆅ䛾఩⨨䠛– PKT䛻㏆䛔┅ᆅ䛷䛿⦆࿴䛜㐍⾜– “Main topographic rim” 䜘䜚ෆഃ– 㞄᥋䛧䛶䛔䛺䛔ሙྜ䜒䛒䜛– ෆഃ䛛䜙2␒┠䛸䜘䛟ᑐᛂ䠄౛እ䜒䛒䜚䠅

䠄Fig. 5䠅䠄ᅗ♧䛫䛪䠅

Excavation cavity 䛸䝸䞁䜾ᵓ㐀ᐇ㦂ⓗ◊✲䛸ᩚྜⓗ 䠄Housen et al., 1983䠅– ኱䛝䛺䜽䝺䞊䝍䞊э ཌ䛔䜲䝆䜵䜽䝍
䠄Crisium ┅ᆅ䛷䛿15km !䠅
– 䜔䛿䜚≉䛻኱䛝䛺3┅ᆅ䛿ⷧ䛔

Schultz (1988) 䛾⌮ㄽ䛷䛿ㄝ᫂୙㊊–

Excavation cavity ࿘ᅖ䛷䛿ᆅẆ䛜ཌ䛔䜒䛧ᙧᡂ᫬䛻Main rim 䛜䛒䜛䛺䜙䞉䞉䞉– 䜲䝆䜵䜽䝍䛷ぢ䛘䛶䛔䛺䛔ྍ⬟ᛶ䜒༑ศᅗ䠖䜰䜲䝋䝇䝍䝅䞊䛛䜙䛾䝈䝺䠄Fig. 5䠅

䠄Fig. 6䠅䜰䜲䝋䝇䝍䝅䞊䛛䜙䛾䝈䝺䜎䛸䜑ᨭ䛘䛶䛔䜛Ⲵ㔜䛸Cavity┤ᚄ䛿ẚ౛䠛– 䜔䛿䜚኱䛝䛔Serenitatis, Imbrium 䛿㝖እ2ᒙᆅẆ䝰䝕䝹䛻䜘䜛ෆ㒊ᵓ㐀䚸 Excavation cavity 䜢᥎ᐃJolliff et al. (2000)

Cavity䛷䛷䛿䛺䛟䚸┅ᆅ䛾఩⨨䠛኱䛝䛺3䛴䛾┅ᆅ䠄Serenitatis, Imbrium, SPA䠅 ௨እ䛷䛿䚸䝇䜿䞊䝸䞁䜾๎䛻ᚑ䛳䛶䛔䜛– Excavation cavity 䛾῝䛥䞉┤ᚄẚ– 䜲䝆䜵䜽䝍ཌ䛾ศᕸ– PKT䛻㏆䛔┅ᆅ䛷䛿⦆࿴䛜㐍⾜᭶䛾⾲ഃ

Procellarum KREEP Terrane(PKT)᭶䛾ከ㔜䝸䞁䜾┅ᆅ䛷䛿䚸Main terraced rim 䛿ཌ䛔䜲䝆䜵䜽䝍䛻䜘䛳䛶㞃䛥䜜䛶䛔䜛䛾䛷䛿䠛኱䛝䛺3䛴䛾┅ᆅ䛿䚸䝇䜿䞊䝸䞁䜾䛛䜙ண䛥䜜䜛䜘䜚䜒ὸ䛔
Image credit: NASA/ᅗ䠖䜰䜲䝋䝇䝍䝅䞊䛛䜙䛾䝈䝺䠄Fig. 5䠅