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1�@�{“¡ –Î, ‰F“s �_ŽO, “àŠC –Î�@�i1990�j�åŠâ’n”M’nˆæ“ì•”�C“û“ª�E�‚‘q‰ÎŽRŒQ•¬�o•¨‚ÌK-Ar”N‘ã. ’nŽ¿’²�¸�ŠŒŽ•ñ�C41�C395-404.�@Suto, S., Uto, K. and Uchiumi, S. (1990)K-Ar ages of the Nyuto-Takakura volcanic products, southern part of the Sengan geothermal area, northeast Japan. Bull. Geol. Surv. Japan, vol. 41970, 395-404. 931
2�@�åŠâ’n”M’nˆæ’nŽ¿�}•Ò�WƒOƒ‹�[ƒv�i1985�j10–œ•ª‚Ì1�@�åŠâ’n”M’nˆæ’nŽ¿�}�à–¾�‘�C“ÁŽê’nŽ¿�}�i21-2�j�C’nŽ¿’²�¸�Š�C23p.�@’nŽ¿’²�¸�Š�@Research group for the geological map of Sengan Geothermal Area, scale 1 : 100,000. Miscellaneous Map Sereis (21-2), Geol. Surv. Japan, 23p. (in Japanese with English abstract) 797
3�@�‚‰ª �é—Y, �¡“c �³, ‘å�ê —^Žu’j, �¡–ì �Kˆê, ”Ñ“c ”ü•ä, �{“¡ �O, ”¼‘ò Œb“ñ, “ìŠÙ —L�i1988�j•S–œ”N‚æ‚èŽá‚¢‰ÎŽRŠâ‚Ì‚j�|‚`‚’”N‘㑪’è.�@•¶•”�ȉȊwŒ¤‹†”ï•â�•‹à‘��‡Œ¤‹†�i‚`�jŒ¤‹†�¬‰Ê•ñ���‘�i�º˜a62”N“x�jŒ¤‹†‰Û‘è”Ô�†60303011�Cp.1-43.�@Takaoka, N. et al.(1988) Absolute age datings of volcanic rocks younger than 1Ma. in 'Res. Rep.Monbusho Sci. Res. Program General Research (A)"Absolute age datings of volcanic rocks younger than 1Ma"', 1-43. 975
4�@NEDO (1991)•½�¬2”N“x‘S�‘’n”MŽ‘Œ¹‘��‡’²�¸�i‘æ‚RŽŸ�j �Lˆæ”M�…—¬“®Œn’²�¸�@�H“c‹î’n‹æ’n”M’²�¸�¬‰Ê�}�W�C119p.�@ 612
5�@�{“¡ –Î�C�Έä•��­�i1987)�@Ž´�Î’nˆæ‚Ì’nŽ¿.�@’nˆæ’nŽ¿Œ¤‹†•ñ���i5–œ•ª‚Ì1�}•��j�C’nŽ¿’²�¸�Š�C142p.�@Suto, S. and Ishii, T. (1987) Geology of the Shizukuishi district. With Geological Sheet Map at 1:50,000, Geol, Surv. Japan, 142p. (in Japanese with English abstract 5p.) 927