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Coupling geophysical investigation with hydrothermal modeling to constrain the enthalpy classification of a potential geothermal resource.

Jeremy T. White·Arkadi Karakhanian·Chuck Connor·Laura Connor·Joseph D. Hughes·Rocco Malservisi·Paul Wetmore
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Abstract

An appreciable challenge in volcanology and geothermal resource development is to understand the relationships between volcanic systems and low-enthalpy geothermal resources. The enthalpy of an undeveloped geothermal resource in the Karckar region of Armenia is investigated by coupling geophysical and hydrothermal modeling. The results of 3-dimensional inversion of gravity data provide key inputs into a hydrothermal circulation model of the system and associated hot springs, which is used to evaluate possible geothermal system configurations. Hydraulic and thermal properties are specified using maximum a priori estimates. Limited constraints provided by temperature data collected from an existing down-gradient borehole indicate that the geothermal system can most likely be classified as low-enthalpy and liquid dominated. We find the heat source for the system is likely cooling quartz monzonite intrusions in the shallow subsurface and that meteoric recharge in the pull-apart basin circulates to depth, rises along basin-bounding faults and discharges at the hot springs. While other combinations of subsurface properties and geothermal system configurations may fit the temperature distribution equally well, we demonstrate that the low-enthalpy system is reasonably explained based largely on interpretation of surface geophysical data and relatively simple models.

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Journal of Volcanology and Geothermal ResearchArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 38.38042167460681° to 41.62776153144345° latitude; 42.34130859375° to 47.8564453125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Jeremy T. White, Arkadi Karakhanian, Chuck Connor, Laura Connor, Joseph D. Hughes, Rocco Malservisi, Paul Wetmore. 2015. Coupling geophysical investigation with hydrothermal modeling to constrain the enthalpy classification of a potential geothermal resource.. https://doi.org/10.1016/j.jvolgeores.2015.03.020

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