| Title | Multicomponent Thermodynamic Geothermometry and Geochemical Modeling of Submarine Hot Springs in Northern Dominica |
|---|---|
| Authors | Scott W. Herman, Andrew P.G. Fowler, Kenneth Alexander |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | Geothermometry is commonly used to estimate geothermal reservoir temperatures prior to drilling. It provides insight into deep reservoir temperatures without the logistical and financial requirements associated with drilling. In the early exploration stage, it enables the distinction between more and less attractive prospects. Empirical geothermometry, AKA ‘traditional’ or ‘classical’, has been widely used in geothermal exploration due to its simplicity. However, it lacks precision and has numerous complicating factors. In contrast, multicomponent thermodynamic geothermometry (MTG) combined with geochemical modelling offers increased precision, increased insight into geologic and hydrologic conditions, and the ability to test some of those conditions, thereby increasing exploration confidence. In northern Dominica, where previous studies focused on the onshore hot springs, we sampled two submarine hot springs, because their high pressures make them essentially comparable to in situ samples collected from a geothermal borehole. In addition, we chose to apply MTG and geochemical modelling. This approach provided us with more precise temperature estimates and increased confidence that we were adequately addressing potential geologic and hydrologic complications. MTG of the submarine hot springs yielded a significantly narrower range of estimated reservoir temperatures compared to earlier empirical geothermometry (~75% improvement). This enhanced precision gives us more confidence in the deep reservoir temperature estimates, thus reducing development risk. This paper presents our methodology and findings from northern Dominica and outlines the business case for employing MTG combined with geochemical modelling as key techniques for geothermal resource assessments in diverse geological settings. |