9
腇腈 .3 (,**.) , 1-2+ 腠腌腊腉腇腆腍腅腣腁腃腄腙腔腏腚腐腗腦腓腈腀腋腂腡腝腜腞 腥腕腑腐腗腎腖 , / 腛腡腂腢腐腒腟腘臸致 膢臨 腈腈 膝腷腈腈腈 腶臛腺臬 腈腈腈腈 ,**- , +- 臭膳臶,**. - - 臭膳Thermoluminescence Dating of the Latest Lava Domes at Unzen Volcano, NW Kyushu, Japan Eruption History of the Past ,/,*** Years after Myokendake VolcanoTakehiko YAMAGATA , Isao TAKASHIMA 腂腂 , Koichiro WATANABE 腂腂腂 and Eiji IZAWA 腂腂腂腂 Thermoluminescence (TL) ages are obtained for ,2 samples from domes and debris avalanche deposit of Younger Unzen Volcano. Weighted mean ages are ..+*.2 ka for Tenguyama lava, -.2*.0 ka for Shichimenzan lava, -.+*.0 ka for Fugendake-sancho lava, -..*.0 ka for Kazaana lava, +/, ka for Myokendake lava, ,/. ka for Kunimidake lava. Six TL ages for Tarukidaichi debris avalanche deposit range from ,*, ka to -*- ka. We success to distinguish individual dome age by TL dating. Source rock of Tarukidaichi debris avalanche deposit is Kunimidake lava and age range of formation is estimated as ,/ ka to 1.- cal ka by TL dating and field observation. We gave new and useful age data of Younger Unzen Volcanic lavas by TL dating with age range about ,/ ka to - ka. Key words : Unzen volcano, thermoluminescence dating, Myoken caldera, devris avalanche deposit, collapsed age +腅腃腆腄 腹臍膀膪腙腟+33* ++ 膖腞臀膋腜臆臁膊臯臱腎 膫腠腖腔膜+330 0 膖腝膅臫腎膷臔腓腦腠腙腝膀膥 腣臧臋腜腛腎臗臱腒臗腏腞臃腎臜腨腧臗臙腜臲 膂腎腢腔腥腑腧腔腐腞膀膅臫腞臅腵臕腞腔腡腞膾 膈臕腚腚腢腝膀膪膺臻腞臒膿腝腗腊腘腢臊臣腜臡 膤腎膠腨腧腹臍膀膪臞膱臄腚腒腘腠腚腡腥腧腘腊腦 臉膸+33/腆腁 腐腞臟腙腟臂膉腹臍膀膪腩臂腒 腊腢腞腍腥膼腝至膪膀膪臷膙膄膀膪膘膄膀膪膄膀膪腝 - 膓臼腒腘腊腦腹臍膀膪臞膱臄腝腟臓自臇腞膺臻腞臮臘腎膌膦腑腧 腘腊腦腎臟臥 (+331) 腎膰腒腔腤腋腜臢膉腞腉腎膺膯膉腞膁臝腰腫腪腬腴腳腩膩臈腓 腦腔腡腝腟臮臘腲腃腯腞臇腎腠腕膹臼腚腟腊腌腜腊腈腈 2+,2/2+ 臺腽膬臩膓臰膨 0+*+ 膒膵臙膃臙膃腸膞膃膗膏腾臞膎膮膚腭腮腱腳臏膟 Earth Resources Engineering, Master Course of Graduate School of Engineering, Kyushu University, 0+*+, Hakozaki, Higashi-ku, Fukuoka-shi 2+,2/2+, Japan. 膛膽臖 : ,0**2,0 膬臟腼膓臂臵臠 + 臐臤膡膑腅膆腆 膍膻膗膏膽 Present address : Research Laboratory, Kawatetsu Mining Corporation, +, Niihama-cho, Chuo-ku, Chiba-shi ,0**2,0, Japan. *+*2/*, 膶臥膬膲膕膃腻臠 ++ 膶臥臙膃膞膃膮膚膃臹臑膧膮膚腭腮腱腳膗膏膭臌 Research Institute of Materials and Resources, Faculty of Engineering and Resource Science, Akita University, ++, Tegatagakuen-cho, Akita-shi *+*腈腈腈 腈腈腈腈 2/*,, Japan. 2+,2/2+ 臺腽膬臩膓臰膨 0+*+ 膒膵臙膃臙膃腸膞膃膗膏腸臞膎膮膚腭腮腱腳膞膃臹Department of Earth Resources Engineering, Graduate School of Engineering, Kyushu Uni- versity, 0+*+, Hakozaki, Higashi-ku, Fukuoka-shi 2+,2/2+, Japan. 2+,2/2+ 臺腽膬臩膓臰膨 0+*+ 膒膵臙膃臙膃腸膞膃膗膏腸臞膎膮膚腭腮腱腳膞膃 腇腄腋膐膴 Professor of Emeritus, Department of Earth Re- sources Engineering, Graduate School of Engineering, Kyushu University, 0+*+, Hakozaki, Higashi-ku, Fukuoka-shi 2+,2/2+, Japan. Corresponding author : Takehiko Yamagata e-mail : [email protected]

KZN49203X ˘ ˇ ˆ ˙˝˛˚˜ ˛ ! "# $ %& ’ "# $ ()*+,-./0 11( 2 ˘ 345 ˛6 7 8 9*( :;< ˇˆ=>?@A ˙˝ ˛BCB ˇ ˚˜( ! 1 TL"#A ( DE/ $% FGH8 I &’(JK./L 9/M (N 1 CB(FGH8

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Page 1: KZN49203X ˘ ˇ ˆ ˙˝˛˚˜ ˛ ! "# $ %& ’ "# $ ()*+,-./0 11( 2 ˘ 345 ˛6 7 8 9*( :;< ˇˆ=>?@A ˙˝ ˛BCB ˇ ˚˜( ! 1 TL"#A ( DE/ $% FGH8 I &’(JK./L 9/M (N 1 CB(FGH8

� �� ��� � .3� (,**.)� ,� 1-�2+�

���������� ��������������������� ! ," /#��$�%&'�

� � � �� � ��� �������� � � �����

�,**-� ,� +-���� ,**.� -� -����

Thermoluminescence Dating of the Latest Lava Domes

at Unzen Volcano, NW Kyushu, Japan

�Eruption History of the Past ,/,*** Years after Myokendake Volcano�

Takehiko YAMAGATA�, Isao TAKASHIMA��, Koichiro WATANABE���and Eiji IZAWA����

Thermoluminescence (TL) ages are obtained for ,2 samples from domes and debris avalanche deposit of

Younger Unzen Volcano. Weighted mean ages are ..+�*.2 ka for Tenguyama lava, -.2�*.0 ka for

Shichimenzan lava, -.+�*.0 ka for Fugendake-sancho lava, -..�*.0 ka for Kazaana lava, +/�, ka for

Myokendake lava, ,/�. ka for Kunimidake lava. Six TL ages for Tarukidaichi debris avalanche deposit range

from ,*�, ka to -*�- ka. We success to distinguish individual dome age by TL dating. Source rock of

Tarukidaichi debris avalanche deposit is Kunimidake lava and age range of formation is estimated as ,/ ka to 1.-cal ka by TL dating and field observation. We gave new and useful age data of Younger Unzen Volcanic lavas

by TL dating with age range about ,/ ka to - ka.Key words : Unzen volcano, thermoluminescence dating, Myoken caldera, devris avalanche deposit, collapsed age

+� � ����� !� +33*� ++�"#$�%&'()*+,-./0� +330� 0�123+4567- 1� �8�9:;�%<+=*>� =?"@�+ABC=D%EF+G/HIC/J K"�23"LMN"/O"PQNRRG1� ��ST"UV1WXYGZ�[%\]+^BC� ����_`aR>Y-ROHCYX7

� �bc� +33/�J K"d !� ef����ge>XG"hHi1j���klm��� �nm��� m��1 -op>YX7J����_`a1!qrs"ST"�t+uvICYX7+� dw (+331) +x>/yz%{f"�N1��WS�RS|f"}~������g��67/O1!� �t���"s+-��pR!X�%XJ

��

�2+,�2/2+ ����o�� 0�+*�+��D�D�������_���� ¡�¢£Earth Resources Engineering, Master Course of

Graduate School of Engineering, Kyushu University,

0�+*�+, Hakozaki, Higashi-ku, Fukuoka-shi 2+,�2/2+, Japan.¤¥¦ : �,0*�*2,0 §��d¨oe©ª +«¬­®�¯� °±��¥Present address : Research Laboratory, Kawatetsu

Mining Corporation, +, Niihama-cho, Chuo-ku,

Chiba-shi ,0*�*2,0, Japan.�*+*�2/*, ²w�³´�µª +�+²wD������¶·¸��� ¡���¹ºResearch Institute of Materials and Resources,

Faculty of Engineering and Resource Science, Akita

University, +�+, Tegatagakuen-cho, Akita-shi *+*�

���

����

2/*,, Japan.�2+,�2/2+ ����o�� 0�+*�+��D�D�������_���� ¡���¶�Department of Earth Resources Engineering,

Graduate School of Engineering, Kyushu Uni-

versity, 0�+*�+, Hakozaki, Higashi-ku, Fukuoka-shi2+,�2/2+, Japan.�2+,�2/2+ ����o�� 0�+*�+��D�D�������_���� ¡���¶���»¼Professor of Emeritus, Department of Earth Re-

sources Engineering, Graduate School of Engineering,

Kyushu University, 0�+*�+, Hakozaki, Higashi-ku,Fukuoka-shi 2+,�2/2+, Japan.Corresponding author : Takehiko Yamagata

e-mail : [email protected]

Page 2: KZN49203X ˘ ˇ ˆ ˙˝˛˚˜ ˛ ! "# $ %& ’ "# $ ()*+,-./0 11( 2 ˘ 345 ˛6 7 8 9*( :;< ˇˆ=>?@A ˙˝ ˛BCB ˇ ˚˜( ! 1 TL"#A ( DE/ $% FGH8 I &’(JK./L 9/M (N 1 CB(FGH8

����������������� � ������ ������������������������� ������ �� �������� !"#$%&'(")�� *�+&�� +33-, -�������.���� �/01"2%3 *45TL678, �� *9�&��� +33+ ; Takashima and

Watanabe, +33., �:; <=:;�TL�����>� ?@A��-���BC

D !"���EF�#GH�IJ *Aitken, +32/ ;

$%&&K� +322,� ��-'�()=� *LMNO���� P (� +,� �MQG;-�6R./S�� � D TU�0S��; *&K&$%� +322 ;

Takashima, +32/ ; Takashima and Watanabe, +33.�,�TL����VW 6XY912 ��MQG;3Z�B��� [4B56&78= D ��M��=\;� ]^� ��=� 9_�:;M<=R^�� >? (Takashima et al., ,**,)6*L@`AB 1Ca*�D&�� +333, =EFG �H6bc dIMJVR� +*�45 bc=��MQG;X6�eK6Bf^� LMH EFg/�h=� ����'i �����&�jN��O TL�M ,**k4H��R�� lPm�QnR�; *�D&�� +333 ; 9�&��� +33+ ; Takashima and Watanabe, +33.,� TL� ��TU� RS�RT �Uo=�pEF=\; +.C�� Qn6pq�VrGMWR� XsG�JYS��; *9�� +33/,� +.C��!8; TL� Z[� \0t]�� I :�]�S�^;eKG :;P (=BD��-����_M`a��=\;X6=:J� bcu v+de�=����_� p �MQG�; *9�� +333,� X qw�� TL����*LMNO�_ <�fg!"6�whi:;�� �x�S�^y�� :z l�=:; +TqJj����M��=\;�kEF=� RS{H ,Tl26mnS��^������ *��&op� +33/, �q8;����������� r|���M}s8;����� TL��MQG^� ]^� ~t�9t=:f^ucv'��B����O TL�MQG� ��t6mnS�;�_ wx�y� Xz�{�q;�O|<r��p�}R��O ~t�_M~�R^� �R� X�H TU{H� ,T /S4� ����'i ��y�������M�f^�

,� �����������������P� ��u�+�� ����P��8R� ��y��q;\0O�o �)pNG�

�� ,* km, �� ,/ km 'i�(�R�;� X �8� ��M���(�8;����+'� *�k�+313, �����R� ]^����PM�����;y���{H����i +** km��^��B�8M�G;� ��_ ��P���G ���{HB;��'��:f� VWp�����R��R���;*��� +32.,������ 9�� �SP�BC�� #��@� ��_6� ���� ��� r|�� )�BC ��+�M��qD^8�� ��_6{HB;� ���� ',�(-���*A��� R EF�:; *k�� +3-0 ; Hoshizumi et al., +333 ; ��� +32.�, �� �*���], ��*���� ¡¢¡'6 �;X6p:J� �_�£ H5¤¥�9t_B6XYplP^f�;�y��� @��_� /*T{H +*RT� ���_� +*TqJpj�6Qn *��&op� +33/, S��;�� RT4� ����_ y�� ¦t¡(=B�� BI� X� \�y�� +00- @¢�� \0� +13, �¢�� \0� �R� +33*

qJ£]f^y�6���;�§� TL������ ����',¤ *��&op� +33/, M¨�©¥R^� ', ª¦� ��©¥�8���_§ �¨&« TL� *ucv'��B����O����Uo, M Fig. +�WR^� 45���©¥M�f^��_6�,&©¥�8���[4�©¬;�

+) r|���� ���,��Mª68;Iq�`. km ��_=:J� ���­�^` +./ km «®'}MX8;� k��� r|�&¯|�BC{HB;ª��_6�-�(�8;¬���jN��O��lk��jN��O{H°sS�;� k�­=� ±(�²�®¯M°?�R� '}Mp6�±���(M�����³�r|���r|���� ]¯|���6´µX6�8; (Fig. +). �*�¶�p��*���� ¡¢¡'=:;�� ²·= ��¸³=:f^� r|���M .k� ¯|���M 0k©¥R^�

,) �����´R ��N-�����{H°sS�� � \0�8r|� «®µ ¶���=BD� «®µ ���p[WR�;� r|� «®'}¶�\0R^ -� ����� *·¹��� ����¸��� �� ��, � �,��aA|s�£��qD ^��* ¡¢¡'{HB;� �����=� ����¸= -k� ·¹= ,k ��M©¥R^�

-) ���� �=p����88;����� ����88;���6����88;�.� ,� �

��¹º&9� º&��»l�&¼»L¼74

Page 3: KZN49203X ˘ ˇ ˆ ˙˝˛˚˜ ˛ ! "# $ %& ’ "# $ ()*+,-./0 11( 2 ˘ 345 ˛6 7 8 9*( :;< ˇˆ=>?@A ˙˝ ˛BCB ˇ ˚˜( ! 1 TL"#A ( DE/ $% FGH8 I &’(JK./L 9/M (N 1 CB(FGH8

������������ ��� �� ������������������� �!�� "����#$�%&��'(��))�$*+,-.�� ������/��� /01 �2�� ,0�3�456,7���"$1 8�9:�8�9:�;�<�=>�

00�3�456,7� =>��? �7@�� �$A cm� /* cm�����B�C(��D'�EF$GH�-IJ13��KL,7 ,:����� +/M,* cm��N�OP�� 4�QR$S -0TU,7�����1 =>4�V�W�X�$Y ,�- cm���Z[\�]^_'`a �7� ��]^_��b_c $d.- ,*��ef�g�4hi7)�j1 +./*2�+./+-�k4l,7�)� 1mnop��q r��sOt1 +312u �v�w'x.� ��$yJ1 8�9:�;�<�=>�z{�|'}� ���~z1 � ,20�3�$d.-1 TL�|g�4hi

7� �� �3��1 ������1 �;�<�=>�� �!�� .���3���� '��.OP���456,7� �� �3��56:������) TL�|g���4H)�- Table +$l,7�

-� � � � �-�+ TL����TL�|g�!�~X�yV$hi7�3� /** g4c]��c"��#�#4���.yV��,-$?,1,*���� (*.2.mm) ���.4� %� �7� ��3�� ,3* g4��$& ,1 'N 2*mm, x .*

mm��_c����(�$��1 ) w¡¢�£4hV g¤c¥��¦��§*3�),7� ¨J� ,+* g

4� ' 0*�������.4%�©�H�ª�$?,1 0*M,**���� (*.,/M*.*1.mm) ���4T+,7� $?3��m�«¬�­®��¯°�±$yJ�\²4�,,1 ³´µ¶-·�¢´$yJ¸·1 ¹

Fig. +. Geology and sample locations of TL dating with weighted mean and range of TL ages of 0 lava units andone debris avalanche deposit (Geology is simplified from Watanabe and Hoshizumi, +33/).I : Pyroclastic flow and fan deposits of Younger Unzen Volcano, II : Heisei Lava, III : Shin’yake Lava, IV :

Shichimenzan and Tenguyama Lavas, V : Fugendake-sancho, Kazaana, Shimanomine, Senbongi, Inaoyama

and Taruki-Higashi Lavas, VI : Tarukidaichi Debris Avalanche Deposit, VII : Myokendake Volcano Main

Volcanic Edifice (m : Myokendake Lava ; k : Kunimidake Lava), VIII : Nodake and Fukkoshi Lavas, IX :

Older Unzen Volcano

S : Shichimenzan, T : Tenguyama, Ta : Tarukidaichi, Ka : Kazaana, F : Fugendake, K : Kunimidake,

M : Myokendake

.º®»�¯�c!$y�O¼���������|g� 75

Page 4: KZN49203X ˘ ˇ ˆ ˙˝˛˚˜ ˛ ! "# $ %& ’ "# $ ()*+,-./0 11( 2 ˘ 345 ˛6 7 8 9*( :;< ˇˆ=>?@A ˙˝ ˛BCB ˇ ˚˜( ! 1 TL"#A ( DE/ $% FGH8 I &’(JK./L 9/M (N 1 CB(FGH8

���������� ��� ���������������� Takashima and Watanabe (+33.)!"#$ (+33/) %&'(���TL)* �+�,�� (+)-./*�01�234

� 5+�,����� (,)67 TL89 :,+�,;<=� g 4&3>?@����� (-)23ABCDE� :,)F4� GH >�I- �JK=LMNOPQR+�ST (+), (,)�����UV�� W(X

-/*YZ[\]^_9`X ��N-./*�01�234� (Paleodose, PD)N:,X(+� abcd]e

:,+�R�f�� ghi4j k#$lKm +323n ���)F4� (Annual dose, AD) :,+�R�f��

��o23ABC (U, Th, K,O) !"Zpqr�rs tf�GH��� 23ABC��� uv ,3*g

������ g 4ew^xyzx{]j ����o (U, Th, K,O) DE� ��� Zpqr������ +*/YQ|��}~+�Q��'��>���`X:,�� W(X�`X Aitken (+32/)!" Bell

(+313)�]��J��)F4� H���� �� ��qC���+�������Q��������

Table +. Locations and TL age data of ,2 samples collected from Younger Unzen Volcano.

����l#$ �l�� ¡¢l£¤�¥76

Page 5: KZN49203X ˘ ˇ ˆ ˙˝˛˚˜ ˛ ! "# $ %& ’ "# $ ()*+,-./0 11( 2 ˘ 345 ˛6 7 8 9*( :;< ˇˆ=>?@A ˙˝ ˛BCB ˇ ˚˜( ! 1 TL"#A ( DE/ $% FGH8 I &’(JK./L 9/M (N 1 CB(FGH8

����� +* mm���������� � ������������� a���������� ������ ����� � !�� �" b����#$%�&��'�������� ��(� (+333)������$���� ��)*� ��$+�&� , !�-� CCD./0$"#&�$12%3$��� 4�5678�& ��'(��9$)*&�� :�;� 3< +=���� >=,���� $-*���?�./0 @AB� +3/1C �DE�F���� $G?��:&� ,H��9�12��34�D�I56J�9$Mejdahl (+313)�DE+=���7� b��8K�8�2�?� �'��$L9&��M:;��� N<�0�<O TL�=$G?��

TLage@kaCP PD

AD��+Q� �������

�� � s�>?R��@A$S TE� d��'���US T���V� B1�)*�� CWX./*Y� ,**Y�� DW�Z� EF[��G\] HI^_7`�Jabcd.ef1K�LMg$��hO�� N1O?� //*�0/* nm T�� ��� g�PQ�RSTiji�UVWkXlYQ��� 0*Co (/.+*m+*+, Bq)$��� YQZnFo[�)*� 10m10 mm�NaIp9q @r�1s@tCC �udvvwxydcz0b{�$\|})Z��� hO��

-�, X��������� !X�~]�*��?� X��^$hO�� !�/��_`$��a�&%ab (�-* mm) �&�� ��%abc ,g$cd�J� !^d����E� d��DE�?�*&���$)*&�� e�&�"f��.iK�gJ RINT,+** � )*h��� Target : Cu

@Ni��d8�C� K� : .* kV, Ki : .* mA, j�k\ :

,�0*�, j�l� : .��� T��

.� � � �

.�+ TL�� ���+=��=m$ Table +�n�� �� � , !>=+=��=m�I56J (TOWM)�:�US(sOWM)$N<�0DEG?� �=K�8�&��

TOWMP���

��Ni*Ti�

sOWNPTOWM*

���

�� � Ti�,H� TL�= TE� 5| Ni� si$,H��=US�&� NiP(Ti/si)

, �#&������)*�� ��H� !�US�o�;T����� ,�3� !p������>=� I56JUS$ , s�&��,q������rstu����v4]� !

�� w�q�� ,�>=���q�x� 0�� �3�DES�T��� US$%��� ¡¢y&��=$n�� M�z�I56J�=�{£�¤|q�� -.+Q*.0 ka� M�¥��=����q�� ,/Q. ka TE��� �}¦���=��§¨4�0>=~����=���&��� ©��=��o�x�� ���%ª�V��«�¬/$h­�

.�, ���������� TL�=$)*&�,�3� ��®¯]�������rstu����v4]�°±¯���²�Z�T����3�-�� X��^�D�³�~]�p����´ª$hO��

X��^�,�3� TL)* !>= +�X0�$��&hO�� p9��~]�� ��� `e�_a0b_� �?�� µ¶�� ·�� TE� 1�;�o[�$ .¸�&� Table ,�n&�� ,�3�����T��� ����� `e�_a0b_(µ¶�(·���[

Table ,. Mineral assembly of Younger Unzen Volcanic

rocks identified by X-ray di#raction.

�d�y¹ºx���D��»¶�¼¤q������=)* 77

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Fig. ,. Photomicrographs of lavas from a) Myokendake

lava (SB-**1), b) Kunimidake lava (SB-*+-).

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Fig. -. Shape of collapsed walls at Myoken caldera.

Abbreviations of location names are same as

Fig. +.

Fig. .. History of Unzen Volcano in recent ,/,*** years and new proposal derived from TL age data. f* :

fission-track age by Danhara et al. (+33-), k* : K-Ar age by Hoshizumi et al. (+333), k** : K-Ar age by

Hoshizumi et al. (+33.). Kikai-Ah and Aira-Tn ashes are widespread tephra derived from South Kyushu,

and the ages are widely accepted.

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� � � �Aitken, M. J. (+32/) Thermoluminescence dating. Aca-demic Press, -/3 p.

Bell, W.T. (+313) Thermoluminescence dating : radiationdose-rate data. Archaeometry, ,+, ,.-�,./.*V +#W,XY#-ZX.#/0/1 (+33-) [�\]W�^_`ab�#�c`d2345�5efg6\]#7]�8f� \]�h�i�h9j:� /+.:klm#n;<= (+322) >�op`q�r? s@XAB2?t �uv\]w�2345� ���C:� ,3,,*1�,+0.DxEFG (+3-0) g6y� \]� H +:� -, 1�+,..-ZX.#zI{m#/0/1 (+33.) g6\]�K-Ar2345fJ|g6\]�KL}f� \]�h�i�h9j:� 3-.

Hoshizumi, H., Uto, K. and Watanabe, K. (+333) Geologyand eruptive history of Unzen volcano, Shimabara Penin-

sula, Kyushu, SW Japan. J. Volcanol. Geotherm. Res., 23,2+�3..n;<=#:klm (+322) >�op`q�r?� ���C:� ,3, 1-�2,.�MN.#~OP. (+320) g6\]���} s��t�\]� -3, ,33�-**.�MN.#QRS (+33+) g6\]� \�T#W����UVW� +.C23�KL}� \]�h�i�h9j:� +.*.X Y#J�Z. (+312) [�������cJK\������^cf����\]w� H��@A� +1,+.-�+0-. D�. (+313) ���*�v\]�]��^�_�Uv�`a� ���C:� +0, +,1�+-3.

Mejdahl, V. (+313) Thermoluminescence dating : beta-doseattenuation in quartz grains. Archaeometry, ,+, 0+�1,.

�� � (+3/1) �W�bcde�Uv��f f¡�uvBg45h�i�&j�f� kl� 0, /�+-.QRS (+331) \]\�W�\\�m¢94� \]�£¤£�¥¦/n#�§o�����ph� +/2�+12.qrsi (+32,) g6mtfu¨y#©Ny#vNy�w�}� xª«��h¬� -1, +-�,3.=/S (+32.) g6\]� xª«� 32 p.yz {#­y ®#/0¯/n#�|XF (+333) \]W�>�op`q�r2345�}g°±fg6\]\�TUVW� b~�}�j�23f� W�� 3.,+*3�++3.

Stuiver, M., Reimer, P. J., Bard, E., Beck, J.W., Burr, G.

S., Hughen, K.A., Kromer, B., McCormac, G., van der

Plicht, J. and Spurk, M. (+332) INTCAL 32 radiocarbonage calibration, ,.,***�* cal BP. Radiocarbon, .*, +*.+�+*2-.

Takashima, I. (+32/) Thermoluminescence dating of vol-canic rocks and alteration minerals and their application

to geothermal history. Bull. Geol. Surv. Japan, -0, -,+�-00.­y ® (+33/) >�op`q�r2345f��@X�uv\]W��45����f� H��@A� -.,,*3�,,*.­y ® (+333) ��­V\]�E]�W²³´�>�op`q�r23� \]� .., ,1/�,11.­y ®#D�µn (+323) �y«h�y���\�TUVW�K-Ar23� TL23�¶� ��·� 3/,2*1�2+0.­y ®#/0¯/n (+33+) +�2u¸[�\]W�23458����g6\]7]Wc� TL23� \]�h�i�h¹�9j:� -,.

Takashima, I. and Watanabe, K. (+33.) Thermoluminesc-ence age determination of lava flows/domes and col-

lapsed materials at Unzen Volcano, SW Japan. Bull.

Volcanol. Soc. Japan, -3, +�+,.Takashima, I., Mori, Y. and Mukaikubo, A. (,**,) Stand-ardization of thermoluminescence dating of volcanic

rocks fProposal of grade check for reliable geologicalagef. Advance in ESR Application, +2, +03�+1,.Qº�#QRS (+322) g6\]������ �������yV��\]»4B@A�¼� +., +�+*./0/1#-ZX. (+33/) g6\]���� \]��� 2� ���HB�

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