Periodic Behavior of the Bubble Jet (Geyser) in the Taketomi Submarine Hot Springs of the Southern Part of Yaeyama Archipelago, Japan

Abstract

AbstractThe periodicity of the bubble jet that spouts intermittently from the Taketomi submarine hot spring in Yaeyama archipelago, Japan, was measured for the first time using an acoustic current meter. The time series analysis of the upward velocity for the data, without a spiky signal, indicates that the cycle fluctuates between 38 and 85 s. Focusing on the period of high and low tide, the dominant time cycles were 66 and 41 s, respectively. These results show that the fluctuation of pressure with tide affected the eruption period of the bubble jet. In accordance with the vertical tube theory, estimations of thermal source and recharge water temperatures were carried out by taking into account the boiling point change due to the tidal variation in hydrostatic pressure. The result indicated that if the heat source temperature was higher than 200.0 °C and recharge water temperature was preheated to 117.96 °C, the observed eruption time cycles at high and low tide were stable.