Assessing the Geothermal Potential of Central America – A Web Based Favorability Map Project
Emiliano Sosa MASSARO, Alejandro PALACIOS, Ulrich STEINER, Achim SCHUBERT
Central American Countries are well known for their great geothermal potential. Although mainly high enthalpy projects have been developed so far, the potential for development is still considered strong, especially in countries where high enthalpy is not yet fully developed. However, additional interest was announced for direct use applications with lower grade, yet economical temperatures. Here, limited costs for shallower wells in areas of high geothermal gradients are expected to initiate new exploration activities in the vicinity of districts with growing economies and energy demands.The study demonstrates an open source data processing workflow for the setup of a geothermal database and a favorability map, using the example of Costa Rica. However, it is intended to be suitable for all Central American countries, when data is available. The favorability map is designed to be available as a web-based geographic information system (GIS) to support local decision makers and international investors to start or proceed with further exploration activities. The assessment of the geothermal potential was made based on the work of Aravena and Lahsen (2013), where fault locations, occurrence of volcanic or sedimentary rocks, seismicity, and the proximity to the volcanic arc and to geothermal surface manifestations are considered indicators for favorable geological conditions. The surface potential for viable projects was derived from infrastructural data available from OpenStreetMap and the Energy Database from the Interamerican Development Bank IDB, distinguishing the sectors industrial, residential, and general. Ancillary data, such as roads, powerlines, protected areas or migration pathways, is made available to provide the user with relevant surface information. A GIS analysis process with weighting factors produced five potential maps for projects including power generation or direct use in the vicinity to the volcanic arc and sedimentary basins. Combined, these maps provide an overall favorability map for geothermal projects. The result was calibrated and evaluated with a known exploration target as a proof of the concept. Finally, a conceptual geological scheme was developed to discuss the geothermal exploration and applicability of the favorability maps.
|        Topic: Resource Assessment||Paper Number: 16067|