鳥取一島根県境の地震(1989-1991年) 前後の周辺の温泉の水質・水温変化について

Abstract

Temporal variations in water quality and temperature at 5 hot or mineral springs (Tamatsukuri, Yuda, Sekigane, Yoshioka and Yudani) in Tottori and Shimane Prefectures have been observed for geochemical research for earthquake prediction.Since October, 1989, the seismicity have been active near the border of Tottori and Shimane Prefectures.We carefully estimated the contribution of meteorological factors and earthquakes to the water quality and temperature and found the water quality at the Yoshioka hot spring and water temperature at the Yudani hot spring are sensitive to earthquake occurrences.Especially at Yoshioka hot spring, the C1￣concentration was anomalously increased just before the earthquake(M 5.9) on August 28, 1991 in the eastern part of Shimane Prefecture.We conclude that measurement of water quality and temperature at a carefully chosen hot or mineral spring should give information useful for earthquake prediction.