Geothermal Research in Greenland

Abstract

Surface manifestations of geothermal activity are rare in Green¬land. They are mainly found in the basaltic areas at Scoresbysund and Disko. The highest temperature is found on the east coast, north and south of Scoresbysund, and the hottest spring is nearby Cap Tobin, 62°C. The hottest one in Disko is around 18°C. A limited investigations have been made into the possibilities of geothermal utilisation in Disko. Twelve small geo¬thermal fields are known there. Most of the thermal springs are found in the basaltic lava pile but three of them are in Precambrian gneiss and one in Cretaceous sandstone. The regional permeability of the basaltic formation in south west Disko seems to be similar to the more permeable part of the Icelandic Neogene basalts such as in NW-Iceland where geothermal utilization is common. The permeability elsewhere in Disko is unknown. The warm springs are most likely connected to fissures or fissure swarms in the bedrock that allow the groundwater to penetrate deep down and form vertical convection systems as is the case in most Icelandic low temperature geothermal fields. Seismic activity is known in the Disko area and the earthquakes can form and maintain permeable fissures and fissure swarms. Changes are known to occur in the tempera-ture and runoff in the warm springs after earthquakes. Nothing is known about the geothermal gradient in Disko.
The warm springs of Unartorssuaq (Engelskmandens havn) are the only ones located near to an inhabited area. They are ca. 2 km outside the town Qeqertarsuaq (Godhavn). They seem to be connected to fissures and faults found in the field and the fissures can be traced towards the town. Chemical analyses indicate that the temperature of the geothermal liquid in the depths might be 50-70°C. Boreholes are needed to investigate the geothermal gradient and the size and orientation of the geothermal system. Until drilling nothing can be stated about the possibilities of geothermal utilisation in Qeqertarsuaq.