Characteristic Periodic Variations of Surface Geothermal Features: a Study of Springs and Geysers Using Wavelet and Fourier Analysis, and System Dynamics Modelling

This study aims to identify and interpret characteristic periodic variations in surface features by analyzing measurements of water level, conductivity, temperature, rainfall and barometric pressure data. The measurements are filtered using an adaptive wavelet based filter to extract the influence of earth and gravity tides, rainfall, and barometric pressure. Fourier analysis is used to further examine the content of the extracted signals. A system dynamics model of a spring is formulated to demonstrate fundamental heat and mass transfer. This study aims to provide an understanding of the effects of periodic forcing functions on geothermal features based on high accuracy measurements taken at high sampling rates. Once the amplitude and frequency of any forcing functions have been identified, these can be monitored to minimise the time to identify and quantify any changes in reservoir characteristics.