Geothermal Spring Temperature Analysis

Abstract

The aim of this study was to examine spring temperaturetime-series data recorded from two geothermal pools, theWaiotapu Geyser in Waiotapu and the Soda Fountain inOrakei Korako. Both springs show cyclic behaviour intheir temperature recordings. The Waiotapu Geyser showsa distinct cyclic pattern throughout some periods followedby periods of constant temperature (around 80 °C), whereasthe Soda Fountain shows persistent cyclic patterns at alltimes.The effects of seismic activity, rainfall, air temperature andair pressure were analysed in order to ascertain whetherthere are any relationships between the spring temperaturesand any of these factors. Seismic events, air temperatureand rainfall did not appear to have much impact on theWaiotapu Geyser throughout the period analysed.However, it was found that variations in air pressure couldset off or inhibit eruptions at the Waiotapu Geyser as wellas affecting its eruption frequency. Generally, duringperiods of high air pressure the geyser did not erupt and itstemperature was constant. However, as the air pressuredropped, the geyser began to erupt; further lowering of theair pressure had the effect of making eruptions morefrequent.The Soda Fountain on the other hand did not seem to beaffected by seismic activity, rainfall, air pressure, or airtemperature throughout the period analysed. This springdid however show a persistent one- to two-hourlytemperature cycle.Recommendations for future monitoring, based on lessonslearnt from this data analysis are: ensuring continuous datacollection rather than discrete datasets; co-recording ofwater level or pressure data; and taking multi-leveltemperature measurements in the spring feed channel.