Microseismic Monitoring at the Basel, Deep Heat Mining Project

The Deep Heat Mining project in Basel, Switzerland aimed to create a cogeneration pilot plant, producing both electricity and thermal energy for district heating, from an Enhanced Geothermal System (EGS). The project is located in the Upper Rhine Graben within the city of Basel, Switzerland. During 2006 the exploration well BS1 was drilled to a total depth of 5000 m. The granitic basement was found at ~2257 m below ordnance datum (bOD). The estimated temperature at 5000 m depth was 190°C. In December 2006 an hydraulic stimulation of the openhole section of BS1, from 4379 to 4750 m bOD, was performed. The microseismic monitoring techniques and results of the stimulation are discussed here.