Origin of Reservoir Fluids from Borinquen Geothermal Field

Abstract

During the different geothermal exploration studies conducted by Instituto Costarricense de Electricidad (ICE), several potential geothermal areas have been detected. One of the most important in the country is known as Borinquen Geothermal Field, located within the Cañas Dulces Caldera, on the Pacific slope of the Rincón de la Vieja volcano, Liberia, Guanacaste, 240 km northwest from San José, capital of Costa Rica. In this sector, the presence of different hydrothermal manifestations that reveal the existence of a geothermal reservoir is noteworthy. The analysis of the chemical and isotopic composition of water coming from hydrothermal manifestations, geothermal wells and springs, have allowed us to elucidate the hydrological and hydrogeological processes carried out in the hydrothermal system, as well as, to define the origin and temperature of the fluids that constitute the reservoir of the Borinquen geothermal field, where two 55 MW plants will be installed.