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  ,*++  /  ,1Ash-Fall Distribution of +113 An’ei Eruption, Sakurajima Volcano
 Revealed by Historical Documents Masashi TSUKUIOld historical documents on +113 AD An’ei eruption of Sakurajima, southwest Japan were collected fromdistal places as well as those from neighboring area of the volcano. These records revealed that the ash-fall front
traveled to the northeast at about /*῍+** km/h, reached as far as Tohoku district +,** km from Sakurajima, andcovered area of ca. ,.-- +*/ km,. Investigation of old documents helped to improve understanding of behaviorof the volcano and environmental e#ects at the time of infrequent and great eruption.
The wide distribution of ash-fall in +113 Sakurajima eruption suggests that there is a high potential that ash
discharged by future eruption of Sakurajima may cover down through the mainland of Japan. We should keep
in mind both physical and economical e#ects of ash-fall in assessing the activity and making the scenario of aneruption.
Key words : Sakurajima volcano, An’ei eruption, old documents, ash-fall,

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Graduate School of Science, Chiba University, +῍--,
Yayoi-cho, Inage-ku, Chiba, Japan ,0-῍2/,,=&>:¸¹IACorresponding author : Masashi Tsukui
e-mail : tsukui@faculty.chiba-u.jp

() * +90

Fig. +. (a) Map showing distribution of +113 AD An’ei Sakurajima ash and its fall-out period.
(b) Thickness of An’ei Sakurajima ash-fall (in mm).
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+113 M NOAppendix. Bibliography on the +113 A.D. An’ei Sakurajima ash-fall, and description of the eruption. (a) O$cial(daily) reports of regional government, o$ce, temples or shrines. (b) Personal records of regional o$cials.
(c) Records of local government o$cials or knowledgeable individuals. (d) Disaster and observation reports
to regional and local government. (e) Others or not clear. * : original record in manuscript (or its copy).
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93

94

ΐῐ῎ ῏ ῑAppendix. Continued.
῕῔ . ῒ῍ῌ