This study evaluates the geothermal potential in an Area of Interest (AOI) in the southeast of Gran Canaria, focusing on location selection near the rift zone and NW-SE vertical fracture zones.
Via a 3D resistivity model nine conductive bodies were identified in the AOI.
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This study evaluates the geothermal potential in an Area of Interest (AOI) in the southeast of Gran Canaria, focusing on location selection near the rift zone and NW-SE vertical fracture zones.
Via a 3D resistivity model nine conductive bodies were identified in the AOI. Then interpretations of the location of these bodies were constructed based on magnetetelluric (MT), density, and S-wave velocity data with geochemical analyses of gas emissions, groundwater chemistry, temperature gradients and the geological history of the AOI. Eventually the geothermal potential of these locations within the AOI was assessed via six criteria: degree of hydrothermal alteration, depth, hydrothermal activity, marine intrusion, top-down area size and fracture density.
Finally a conceptual geological model of the most promising location was made with a sub-vertical fracture system. Several scenarios were tested as part of a sensitivity analysis, all of which are plausible and therefore not irrelevant. In these scenarios key parameters such as porosity, permeability, geothermal gradients, and the permeability ratio (kz/kx/ky) within the fracture zone were varied. One of the main findings was that the 10/10/1 permeability ratio, considered the most realistic for sub-vertical fractures, showed minimal impact on production performance.