cycleofinterplateearthquakealongthesagamitrough ...˘ˇˆ *...

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腜腛腚腗腃腋腉腆腙腝腐腓腑腇腂腄腌腒腕腁腐腖腚腘腏腍腎腔 * 臄膯膧臋臢膽膶膫臌膟自臟膶膫腹膌腺腂 Cycle of Interplate Earthquake Along the Sagami Trough, Deduced from Tectonic Geomorphology Masanobu Shishikura* Active Fault Research Center, GSJ/AIST Abstract A tectonic geomorphological study is one of the best methods of evaluating the timing and the crustal deformation of pre-historic earthquake. To reveal the cycle of interplate earthquakes along the Sagami Trough, I investigated the emerged shoreline topography and the fossilized sessile assemblages in the Miura Peninsula and the Boso Peninsula. The distribution pattern of coseismic vertical displacement during the +1*- Genroku Kanto Earthquake inferred from the height distribu- tion of the paleo-shoreline suggests that the fault source model consists of a dual fault system of the Fault A and B. Fault A is also the source of the +3,- Taisho Kanto Earthquake. The geometry and ages of the emerged shoreline topography divided into several levels indicate that the characteristic earthquake generated from Fault A has occurred about every .** years. One of several events, it is accompanied with a slip of Fault B, which has a recurrence interval of ,***,1** years. Key words : tectonic geomorphology, paleo-shoreline, recurrence interval, Sagami Trough, Kanto Earthquake +腈腅腊腇 +** 腍腪 +* / 腳腂腻腂腠臇膢腸腶腂膉腛腠膔臮臛膕至腯膨腔腬臒腛臻臭膴膞致腰膄膋腂 腼腡臁腧膻腞臊臫腠膏腙腛腈腬腟膟自臟腍腪腔腬臭臕腡膢膝腎 +* - 腳腂腻腂腛腈腬腑腜腎臥 臻臭膴腍腪臥腐腠臔腬腑腜腎腛腏腬腤腗臱腥膾腥臦腛臙腔腬膄膊腂膀膢臭臕腡腂腚膟自臟腩 腫膏膵臍腒腉腳腂腻腂腠臀膢膝腯腧腙腑腜腍腪臭膴腠臤腟臅臅腨臁膱腠膤膘膡臣腾腂腺臺腠臔腕腚膼腔腬腑腜腛腩腫臑臂腞臭臕腷腲腵膉腯腪腍腟腔腬腑腜腎腛腏腬腋腢膙膀膇膃膒腉腠臹 膙臭臕腡腒腈腞臅腠膦腍腪臙膢膝腎 ++. 腜臖臲腒腭腚腉腬 膠臜+331 ; 膑膿,**- 腞腝腆腁 臝膗腠臭臕腡 +3.. 腌腩腣 +3.0 臙腓腗 腖腠膔腐腝膜致臍腒腍腘腗腑腜腍腪臈腠 臭臕腡膰膢膝腩腫臠腐臙腔腬腜膼腋腪腭腚腉腬膙膀膇膃腜臼膃腱膈膂膌膙膄膊腂膀腎 臱腥膾腦臡膀膇膃膒腉腛腡+3,- 臧臘膣臹臭臕 M 1.3臙腓腚腉腬腎腖腭膍膚腟臅致腟臬腪腭腬膄 膊腂膀膢臭臕腡+1*- 膣臹臭臕 M 2.,腓腍腞腐 Fig. +腆腀 腍腪腥腗膳腫腓臗腡膛腟腡腞腘腚腉 腞腉腓腍腓膣臹臭臕腎膕膬腍腪膳腫臙腓腚腏 腗腛腈腮腊腜腉腊膼腋腡臏臫膩腞腝臭膴致臐膭腯膥腟 膺腐腍腪膨腒腭腚腏腗 +3,0 ; Sugimura and Naruse+3/.+3// 腞腝腆腁 膣臹臭臕腠臀膢膝腡臘腜膹腠膢腛 ,,* 腛腈腬腑腜腍腪,**-** 至臸 腜腉腊膎膸腎臥腐 臚膮+311 腞腝腆腀 臁膱腠 GPS 腾腂 腺腟腩腬膁腽腵腸膈腽膄膅腾膉腍腪臖臲腒腭腗臀膢膝 ,**.** 腛腈腬 臃臩+332腆腁 腓腍腓臻臭膴 腍腪膸臛腧腪腭腗臀膢膝腡腑腭腤腛臎臶 +32/2** +333/**0** 膜致臰腐臭膪腉腙膞致臖臲腜臻臭膴膞致臖臲腠膢腛腴膆腽膄腎 * e-mail : [email protected] 腅腇-*/2/01 膐臓膷腙腐腢臆臹 +++ 臯膓臨 1Bull. Earthq. Res. Inst. Univ. Tokyo Vol. 12 ,**-pp. ,./,/. 245

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Page 1: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

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Cycle of Interplate Earthquake Along the Sagami Trough,

Deduced from Tectonic Geomorphology

Masanobu Shishikura*

Active Fault Research Center, GSJ/AIST

Abstract

A tectonic geomorphological study is one of the best methods of evaluating the timing and the

crustal deformation of pre-historic earthquake. To reveal the cycle of interplate earthquakes along

the Sagami Trough, I investigated the emerged shoreline topography and the fossilized sessile

assemblages in the Miura Peninsula and the Boso Peninsula. The distribution pattern of coseismic

vertical displacement during the +1*- Genroku Kanto Earthquake inferred from the height distribu-

tion of the paleo-shoreline suggests that the fault source model consists of a dual fault system of the

Fault A and B. Fault A is also the source of the +3,- Taisho Kanto Earthquake. The geometry and

ages of the emerged shoreline topography divided into several levels indicate that the characteristic

earthquake generated from Fault A has occurred about every .** years. One of several events, it is

accompanied with a slip of Fault B, which has a recurrence interval of ,***�,1** years.

Key words : tectonic geomorphology, paleo-shoreline, recurrence interval, Sagami Trough, Kanto

Earthquake

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!"�#�$%&'�()*�+ �,-./0123�4567�89:;�<=�>)? �@������A()-B5+ C�DE +*-������>)FGEHI+�,-.��HI�J&�)FGE�K)?LM+NOPOQ��A()2R�S�-B5+ � ���TU<VWXY�����C�D&7=FG��+ �,-.�Z@+ �[[�\6]�^_`ab��c�J&�def�()FG�+ TUgh9-Bijk�&���@()FGE�K)? �lm+ �nSopqY�r�n+ �n-B5+ ��9[��s���+ �A�DE�t ++.�GuvXweY) xyz+ +331 ; {|�+ ,**-

9}~? ���-B5 +3..��T� +3.0�@�A�ME+ �� �#��E��0WX��MFG��+ ��-B5�t�DTU�I�A()Gfl�weY)?

<�+ �nSopG��@+ p����n2R�SENOP���SopqY�5+ +3,-����r-B xM1.3~ E�A�eY)E+ �w��@�[0@��w)2R�S�-B5+ +1*-����r-B xM 2.,~ ��9IxFig. +~+ [���OM�U ��5��@59�eY9Y? ���+ �r-BE$����U ��A�eKM�>��GY�fl5+ �;�9}-.0��&�@ I��'�XweKM x¡!+ +3,0 ; Sugimura and

Naruse+ +3/.+ +3//9}~? �r-B�C�D5+ ��G����� ,,*��>)FG��+ ,**¢-**�%£GY�¤¥EHI x¦§+ +3119}~+ 6]� GPSb��@T)¨©k��©2ªb���uvXwMC�D7 ,**¢.**��>) x«¬+ +332~? ���+ �,-.��¥"7�wMC�D5+ FwL�­® x+32/~ E�t 2**�+ ¯" x+333~ E /**¢0**�G��0°I+-±#$/0uvG�,-./0uv���²³©2E

* e-mail : [email protected] x´-*/�2/01 µ¶·=Im¸r +�+�+¹º» 1~

- B � � % Bull. Earthq. Res. Inst.

Univ. TokyoVol. 12 x,**-~ pp. ,./�,/.

¼ 245¼

Page 2: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

���� ��������������� �� ��������������������������� � !"�#$ �% �&'�()*+,-��./0123�45�������6����7��1������,4891�:� �;<�=���>?���@A��B91�CDA�� %�EF�GH�I,J��� �K/<� ��L/�������M$NOP��QRS,TU91� LV� @A��W�XY/�1�Z��D��[��Z��� \�����,��]� � ^�,�������������_`���^� abQc�Z��de1� f�� !"� �����g�h#i��!"�()*+,j. � ^�$k��� �����#$ l�Z��j%91�

,� +3,-���������� �������mFDA/<�&no'p�(q�rwave-cut benchs�tu�1)v����wi���1� @A/����W�%x1�� ���<�C � y�D�_�*. �z{�1� \������|��N�=�� >?���@A/}D+��C~��%x� r��� +3,/s����C(q�<\�)*��tu���1� ,��-. r+3,0s Miyabe r+3-+s �M1�����������/<� �=��/.��>?��� \��0/����1��/�\1 , m��W����������

����1 rFig. ,s� \�)*��23O�<D�����W-,4� �|$� ��u�=��/</5/�NO�� )�D�_ ,m'p�23 � 6��J�� ����7�1������1� ����� ��M6�Z��D�,�9��,�M$�� ^�O�,�e�u� !"����86����,9�/0� i��$k������u!"�()*+�:;,<1���/01���u�$/<�� &no�%�91%��EFN=y�>�!"�D�[�; r�?�[�s /�1�@���(�An/�1����*�� rPomatoleios

Kraussiis <� BC&�'p/m �F¡g��,¢��£D � E¤ �%�91����� �?�[�� ��F/�1 r¥¦2�� +321s� \������§��W � EFE �����*��<� ~¨/Nm /M�©ª91���/01� ^�O�23<\�)*��!"�� �������W-��G�/�1�

-� +1*-���������� �������<� «H�h¬i��I­�z®3����� \������!"�¯J+°±@�,�²�91³´R+n��/����µ�����1 r¶·K2�� +3113s� ����W�86}D+��C~�N¸L¹�h¬i���1�� ������-�^�23<� ��h#���k/����:M�/�1�

Fig. +. Epicenters of the Kanto Earthquakes along the Sagami Trough.

Locations of the epicenters are based on Utsu (+333). Contour interval of

bathymetric chart is +**m.

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¼ 246¼

Page 3: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

������������� ���������������

-�+ ���������� ��������� !"#$%&'()*+, , -�

./0�1234 ���56�7�,�89�:+.*;+.0m 6�7�, ,.*;,.0m�<� =Fig. ->� 56�7��?@ABCDEFGHI��JAB7��<�� 6�7���4K�L�MEFGH�E�A�N��OPQ4�NB=R�ST +322>� ATA ��� U�VW,�X YW��AT�B� ���AMS

���+.C UZ�[\�B��] 03*;1/* yr BP�N^ U,�Q4B =_`�ab ,**+ a>� KB AD+3,- �c�AB�OPQ4�56�!"#$%&'()�+.C U[d� 9�e(fgf U�Ghi[j�kR�l[�mAB��] kRn+/3o,+ ���B=_` ,**->� �4��p 6�!"#$%&'()�qD� �AD+00-;+21, ���� ri��,CsN, AD+00- tu�v/'w[jA�N����xy�<�� z{IUtu�CGH��|��S}74�X~�34�N��OPQ4�, �������[�^�^��� H�[7-GH�AD+1*- �MEFGHt����BQ�N� AB,��6�#$%&'(),MEFGHI��� �JAB�������N�NP���� , -�./0�!"#$%&'()� 6�

TQ56�[iA�NB�� MEFGHI������4tu CDEFGH�?K�� ,,* ��GH�� !�[���Bwf�0� ![j�� ����"#�v'�f�v��$�� !� $������� .* ����~�� ��d��� �8

-.*/ mm� ����uA�N����34�N�=Ozawa et al., +331>� ��M�CD�GH��7%&���<�B��4� ,,* ����� *.1m�uAB������ � ��� ,'�!"#$%&'()��, *.2m�1234B=Fig. ->��TQ MEFGHI�����( +./m�¡¢34� CDEFGHI�S}%£�<�B����s�� �������¤�¥G¦�7���[��AB��] N§47 +.*;+./m� CDEFGH�%&�)¨��©!AB��,*QT���B =_`�ab ,**+ a>� ��ST �J+ª�7 , «,¬A��p !"#$%&'()����­-®� , ¯��Jv/'w,S}%£����<�B��[j��t:�°±TQ �����MEFGH�CDEF

GH�S}%£G² ![��B�°.��Q4��-�, ���������� �/³���� ´µST =+31.> ,��������

56�«¶� =CD/'·[¸X> �-N� �4,M

Fig. ,. Coseismic vertical displacement during the +3,-

Taisho Kanto Earthquake, based on a re-leveling of

benchmarks. Contours are in meters. Compiled from

Geophigical Survey Institute (+3,0) and Miyabe (+3-+).

Fig. -. Two levels of fossilized sessile assemblages

(Pomatoleios Kraussii) in Jogashima, the Miura Penin-sula. M.S.L. : mean sea level. Scale bar is gradu-

ated in +* cm.

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Page 4: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

������������� ��� �������� �� ���������� !�"#���$��%&��' (�)*+,��-��.���/012�3 (�45' �6 �789������:;��<���2�=�>�%��$2��3 ?@�%AB��C�DE�FC�����7' �G��H������3 �7I8�J +** m�K' �LM1NO'��,�>,�=��%' PQR� �+31.� >STU�N��89����.NK1�<>8V�2�=��W�U�=�>�V� �Fig. .�3 ���$>%' ?@�ABNK��7' X��YZ��[U�\1�K' ]&�����3^B �+333� 7���_ ��Q`��F�' PQR� �+31.� ��a������>' � b�!cd"XGef����%g' ������:h�U�������=���%����3 �%�=��i�7'������hj�kE+�#l�$���mn�%oU�=��' p�qr>st��=�>u�2�3 v�' X��1��.�p��N�&��wx>�W�YZ� �� �yz'R�' +311�3 ��>2���{�X��|}�%g' ��>������.�p~�����% �3 (#���Q:��1' ��d�)�F�����>���$�=�>�%��$2��^B' ,***�3 *��)�7' �Q�(#�p~���+M>,�3,����FC�����-.�7' �.�FC�&�Y/�%' ,./1 mm�!����p~������% �� �Ozawa et al., +331�3 =���-�V' ���)*+,��%������.�,������;���a�� �Fig. /�3 (�45' 89����.�78VO�$K' �60���1 0 m��<��Q'�)�� + m���p~�2�������2�=

�>�%��$2�3-�- ����������:;�45�-�' ��������������U����b�&���3 ==�7���+M���k��D���b�FFN(�����u�'Manshinha and Smylie �+31+� �-����� ¡��3¢£��¤3�7' 89����R¥(t�<¦§¨©���=��%' -4G�89����.�(t�b>�����% �3 (=�' Ando �+31.� �89�����ª«¬�5�' ¢£����<����b�Fault A��­a�� �Fig3 0�3 �®7 -*¯�°±²³�> 0.1 m���3 ´6' ,����7�6 �8V��<��Q' �)�p~�2����µ¶$��·U=��%' ,����� �`¸¹�b>������% �3 =��b� Fault B��º��k��D��­a��3 �®7 ,*¯�°±²³�> +, m���3Matsuda et al. �+312� ���ª«¬1,�����

Fig. .. Two levels of emerged wave-cut benches in Kenbutsu, the Boso Peninsula.

Fig. /. Coseismic vertical displacement during the +1*-

Genroku Kanto Earthquake, deduced from height

distribution of paleoshoreline. Contours are in meters.

^B 9»

¼ 248¼

Page 5: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

���������� �� 1*�������� ��������� ���� ��!�"#�$�%�&��'(�������� )�'*+,�-� �.��� /0� 12')�'�3��4�5���67��89:�;��� <= �>���?����

.� ��������� �����������@ABC�DB'12� � E�C�F'"GH� I�JK2"LCM�NOP�QR;��S�T�'"L��U����� VWX�Y Z[�P���-* m\�!�U&� ]9;'^_�-�� `� Imamura a+3,2b Cc� a+3,3b �� E�de"GC�Fde"G'Pf�"G'g����M�Phij�k'lm� L^R9J�f5n�o��� pq�r�j�]'5n� �st��;u� vw'`"G'x��yz�-�� {|�}~;9��J�

.�+ ������������� �!��@AB� � E�de"GP��'�����d��J IK2"L � �� a+32,b �P�� ���������:9 -�'K^����xR9�� ��' I�� � �S�;�9�9 0,***yr BP� .,0**yr

BP� -,+**yr BP���R9� ���F�P�� 1,*** cal

yr BP� /,-** cal yr BP� -,0** cal yr BP��� ����12'"LCM�NO'���<��(�� ]9;'���p��Q��'�����kK��C����+�+./ m'����t�=������]���;���tJ a����0� ,**+bb� �9�9'���'��, �!������ ]9; ��j�k�'�R I�����hij�M?��J]��o��� &�s�@AB� � E�� �Fde"G�T�Y'�k� f"G�� �;g����M���J�5n;9� ���� IK2"L'¡�¢4�£O¤�,'"L��]��;� +¥'�]¦����' I���§�&� ¨t���

.�, "#����������� �!���DB� � E�de"G��Fde"G�"#3©�$'��ª«¬����]��;� ­®¡�a+31.b � '"G�QE�¯"G��F¯"G' ,-'«�°���f5n�o�J� ]9 IK2"L'��L±�;�x&]������DB²³!12'´µ¶K2�� � E���Q·~�.������aFig. 1 ; Sugimura and Naruse,

+3/. ; Yonekura� +31/ ; ¸®� +312 ; ¹®¡�� +32*b�

Fig. 0. Fault source model of the +1*- Genroku Kanto Earthquake. Contours are

theoretical vertical displacements in meter.

�$"L�;(J°�¬�h"Gº�»�

¼ 249¼

Page 6: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

��� -��������� ���������� ���������� !"#$�%&� $'&(�)*+�,-!./01�23&'14 5�6� 78�9: ;+320< ($'&����=>?@�A&�B%"CD��-! ,E-��C��F�GH#$��I014 $'&�C�(JKLMN���� !"#$�%&� JK)*+�,OPQRCA"STG./01���23&'!"# ;Fig. 2<4 UV % ;+32*<(� �)*+�WX01 .������%&Y�E���Z[�\��+.C]^_`�ab"!�Y�E���./]^�5'c'Y�� : 0,+/* yr BP� Y�� :.,-**yr BP� Y�� : ,,2/*yr BP�de014 5�6�

fg % ;+333< ��-!]^QK�hiA'1jk�Y�� : 1,+/* cal yr BP� Y�� : .,3/* cal yr BP� Y�� : ,,3/* cal yr BP�l-1 ;Fig. 1<4 01�-!�)*+�mnop( ,,***E,,1**]�qr&'#4 st� JK)*+�u"!(� WXv#�s�s�����w�� xyz{|�*��1r]^}`�~0"$�%&� $'�G5�]^(��G�-14

-�,�G��01������W�*+�,O*����� ;Fig. /< �� JKW�*+���� ;Fig. ,<��P�#�� �� JK��ST01*� ;�����<���G���l��JKGST01*� ;x�<��G��0� JKGST01*� ;�V< � -u�*

Fig. 1. Paleo-shorelines on Nishikawana, the southernmost part of the Boso Peninsula. Aerial

photo contributed by Chiba Historical Material Research Foundation.

Fig. 2. Schematic geomorphic profiles of Holocene lowlands in the Boso Peninsula. G : emerged area

during the Genroku-type event. T : emerged area during repeated Taisho-type events. Modified

from Shishikura and Miyauchi (,**+).

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Page 7: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

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BP¸N�/,-**9/,*0* cal yrs BP¸e�S1/��-��#�¹=D�S1/�� -�� #5 -,-**9-,+** cal

yrs BP��)5� ¸N� ,,-+*9,,,-* cal yrs BP¸e�

Fig. 3. Seismotectonics model in each area around the Sagami

Trough. G : Timing of the Genroku-type Earthquake. d : rela-

tive vertical displacement. t : time.

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Page 8: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

+�� +,-** cal yrs BP�� 3** cal yrs BP��������� ��������� ������������������ � !"�#$ +%, m&�'(�) *�� +,-��. &� �������*��/0"123������456789:;�<��"=>�?@������A���B) C� DEF"<G'�HIJK� ����DE �(�&�"LM$(��N� OP$+QR� ST" )U��*'��B�

0� �������VW��'�X�Y+,YZ[L \Fault A] "�^�_`a�b�a�c� X�dC+,d B`�e���R� Z����$fc��ZaB� g��\Fig. 3]� h���i��'�� fc��Z��."j�� +�"kl \m�!n ,,***%,,1**�] '�����"opq[L \Fault B] $�Q� X�d rA���^$Z� ������ ��$`asto�"�u� v*�wxy�������� Fault A"z$�B�{+,d g���.'(� \Fig. 3]� |}c� B~��-��."m�!n@����l� X�d'(��v"�� sto�"�u� v"��@l~�aw�����A���B� )��"�� ��v"��@��� ����������i������"��3�

�b� "-�@���"$ Fig. ++'(�� �J'���� Q"�:;6�� �u<G��"���(�$� ��$��*'�B����@��� �b��X�d +,d"�B@�!3�"B�Y"'(c� ��"�y���3��#��B� )"��_� �u����"m�!n�h�'��R� -,***%+,-** cal yr BP������!"!n$�*`�_��z��� �*��)"��$"�<� rA�� + , m&�"456789:;�<"��$(`� ����aB�¡¢ h£�� \¤%¥*� +33*]� |}c<o�¢��u��� $� �"�"<"�¦�_c§¨y�� ©ª���N� ����"��@BR|*«& �aB�¬'F$(�� �­3(®")B /,***%-,*** cal yr BP

�"¢!'«� � m�!n�*¯+ .**� «EY���� +,-** cal yr BP�°±� X�-��.}'"����'«aYm�!n�+ .**�'(��)"¥*� sto� #^"HIJ#� \�# +/./

m] @+,-��.¡"�b� \+..m] '²,,³�aY-"*¯m�!n"´$.����  #^HIJ"�u��@ 0,2**��� �� � /¡"<�ST_cY ,%-m&�#*`� \Endo et al. +32,] ) *��STµ®�aB����b"²,� +,./%+-./ m'(�� �.!"¶±�� �·"0)"¶±¸� \,./1mm��] @1B� � 0,2**�!"2E' +1./m&�¶±�

Fig. +*. Schematic cross-section of geology and geomorphology in the Iwai Lowland. + : terrestrial deposit, , : aeolian

deposit, - : beach ridge deposit, . : backshore deposit, / : foreshore deposit, 0 : shoreface deposit, 1 : marine clay, 2 :

bedrock, 3 : location of radiocarbon sample (number means cal yrs BP), +* : location of archaeological site. Modified

from Shishikura et al. (,**+).

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������� ����� ���� ������� ,*�,+m�������� ��� +���������� +..m�������� � !"��� +.�+/��#$%&�� ��� 0,2**��'(�)��� -�*+� +1�+2�,-�����%�0,2**����� ��.�/0� -2*�.**��������,%&����1%� �-��23��4�%� 56��78���� !"�-��������� +,-** cal yr

BP9�� !", 212�):�� 3** cal yr BP�;�� !"� +,/1�<�= +,3-�>��,?�@�A����� BC������D�������EF�GH I�B�,� J;+.C���KLMNOD������ P!QRLSLTU��V"���� #���W$%,��� X�� +,3-�>���&Y Z+33+[ ,'("\]^B�_HL"/��W$%`a�B�,� 212�):��b)c*+�d,��-e,fgD��2� Zh-i=� +322[� Xjk.�/,���

1� ��������0lm%�� n12o��3p=)�-���qrs4,t�5+� �uvKw����� ?�xU��-��y�6I*+ ZFault A[ �� )�-���yj3d,��*+ ZFault B[ �� z�{��,|�*+%}7D����,8=��~�� '("\]^B%{�9�: ��-���� �0;�Fault A�u��� ?���� +����% Fault B

,�,��)�M�_�� !",�&�B�� 4,�=O�;�8=��~�-���.�/0�

.**���%�����% Fault A� +� !"�������Q�_

�vKw���B� 1m������� ��4�<�� +1./mm���#$D�� �= Z+332[ ,f��S���Q�_HL" Z-*mm��[ ���DB� X� Fault B

%����.�/0 ,,-**�� +� !"�����Q�_��� +,m����� ��4�<�� /.,mm���D��D{�>KLM�?� I�B��J;�KLM�NO�@���r��=� ��AB����B=�3����B� X�� C�8%���� !"�23�4,��D��� q�E�F���G���8��r%�H%��� XjB{|=��B,�D��B���+��

������lm��I= ��hJ�����KL�pM��B�j&X��� X�� *+vKw�#$�2B�� � l�d*+lm�!ML� -N¡��¢£EB�j&X��� �����lm��*O�P���� ��.QR¤��¥¦S+�B�j&X��� §��¨©T�X��

� Ando, M., +31., Seismo-tectonics of the +3,- Kanto earth-

quake, Jour. Phys. Earth, ,,, ,0-�,11.

Endo, K., K. Sekimoto and T. Takano, +32,, Holocene stra-

tigraphy and paleo-environments in the Kanto Plain, in

relation to the Jomon Transgression, Proc. Inst. Natural

Sciences, Nihon Univ., ,+, -1�/..

Oc ª�U-V«W�¬6XY�Z­®8�[¯°±�+333� \ ]^�²³]^�´µ_¶·����`ab�c� d¸¹lm� -2� .+�/2.

Fig. ++. Timing and relative coseismic uplift of repeated Kanto Earthquakes. Open

rectangle enclosed with dotted line means +.C age samples were not obtained.

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Page 10: CycleofInterplateEarthquakeAlongtheSagamiTrough ...˘ˇˆ * CycleofInterplateEarthquakeAlongtheSagamiTrough, DeducedfromTectonicGeomorphology MasanobuShishikura* ActiveFaultResearchCenter,GSJ/AIST

Imamura, A., +3,2, On the seismic activity of Kwanto dis-

trict, Jour. Astronomy Geophysics, /, +,1�+-/.

����� +311� +1*-�������������� �������� � ���� �� ,�� -*� -03�-1..

����� +33+� +,3-��������������������� ����� �!"� +33+� ,� ,/+�,/+.

#$ ��%�&�� +320� ������'�� (������)'�*��+,-� � �!"� /3� +2�-0.

#$ ��./#$�%&0'� +321� ������'�� 1()�2*34�56789:;� <=,-� ,0�.1�/1.

>+,-� +32,� ?@���A./0B�C12� D3� E��� /.� .+F.3G

>+,-� +333� ��4�A./)�0B��HI�JIK� <=,-� -2� /,/�/-+.

Mansinha, L. and D. Smylie, +31+, The displacement fields of

inclined faults, Bull. Seismol. Soc. Am., 0+, +.--�+..*.

%5��� +32/� �LM��NO4� PQ�R� 1� .1,�.11.

%5���-56S�T7UV�8�9:� +31.� ������ �+1*-�� ���;,-� WX<Y�=+Z�> [���?����C12\ : +1/�+3,� �H]KG

Matsuda, T., Y. Ota, M. Ando and N. Yonekura, +312, Fault

mechanism and recurrence time of major earthquakes

in southern Kanto district, Japan, as deduced from

coastal terrace data, Geol. Soc. Amer. Bull., 23, +0+*�+0+2.

%5���@^A��%�_B�`� C�D5�'��aEF�b� c�%dGS�H^I:�HJ<K�%eLf� +322� gMdNO �PQ�h� �iRj �kSlmnoT 1,***���UVpq�r ,����1sm� �t����,-WX�� 0-� ,� +./�+2,.

Miyabe, N., +3-+, On the vertical earth movements in

Kwanto districts, Bull. Earthquake Res. Inst. Tokyo

Univ., 3, +�,+.

H5 u�+Y�Z�`[<\�] v^�%&w_�`ax� +32*� �����b�A./)�0B�C12� � �!"� /-� ,3�...

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-56S�)eEf�%�_B� +33*� g&�� A./�h;)i1|}~�� jk� <=,-� ,3� -+�.2.

Ozawa, S., M. Hashimoto and T. Tada, +331, Vertical crustal

movements in the coastal areas of Japan estimated

from tidal observations, Bull. Geogr. Surv. Inst., .-, +�,+.

l�mnb� +3,0� ������o�� 3��p��qk

rs� ��,-WX�� +� 0/�02.

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��E�� ,***���)'�*���� +1*-��������� ������C�k12� ����� +0� ++-�+,,.

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��E������� ,**+� �����'�� A./���*�� K¡HI�JIK� <=,-� .*� ,-/�,.,.

��E��d¢ £������ ,**+� �����cb¤^���A./��)'�*�����EM�������������� �� ,�� /-� -/1�-1,.

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Sugimura, A. and Y. Naruse, +3/., Changes in sea level,

seismic upheavals, and terraces in the southern Kanto

region, Japan (�), Jap. Jour. Geol. Geogr., ,., +*+�++-.

«¬F^K� ,**-� ­.�g&�®����� �t������0*/�G

«¬F^K���F?K�%J¯�� +311� �����b�������� 0,�� ���°�®±�²�³9��²��}� 3�G

«e�´� +333� ��µ2��� �t������ 210�G.¶�?� +3,/� ������*�;·¸� ��� Sl��¹� +**º� ++�/.G

»5¼�S� +312�������'�A./)'0BNO4�� �!"� /+� -.3�-0..

Yonekura, N., +31/, Quaternary tectonic movements in the

outer area of Southwest Japan with special reference to

seismic crustal deformations, Bull. Dept. of Geogr. Univ.

of Tokyo, 1, +3�1+.

¡4 ¯� +3,3������b�)'0B ������ �!"�/� ++3�+,0.

�Received June ,1, ,**-��Accepted September +1, ,**-�

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