Well Locations - Consideration of Purpose, Objectives and Achievement with Emphasis on Recent Drilling in the Krafla Geothermal Area

Abstract

Landsvirkjun, the owner of the Krafla Power Plant, decided in 2006 to continue exploration drillings for further utilization. A comprehensive research program in NE-Iceland was initiated focusing on geothermal potential with the main purpose to generate electricity. The research program included surface investigations and exploration drilling within four geothermal areas. Several wells were drilled in Krafla, Bjarnarflag (Námafjall), Gjástykki and Þeistareykir to support existing conceptual models and geothermal assessments. The exploration and drilling activities in the Krafla geothermal area will be emphasized in this paper. The Krafla central volcano is located within the neo-volcanic zone in NE-Iceland. The volcano is approximately 20 km in diameter and within it is an eroded and partly filled caldera 8-10 km in diameter. A N5-15°E oriented and 90 km long rifting fissure swarm extends through Krafla volcano, while a prominent NW-SE elongated geothermal area covering ca. 10 km2 is present within the caldera structure. The strategy was to expand previous drilling fields and identify new ones on the basis of a comprehensive TEM- and MT-resistivity survey as well as re-evaluation of previous research work. The purpose of this work is to review the outcome of the drilling activities based on the premises of well siting with examples from a few well locations.