The IDDP has selected the location of its first deep borehole. It will be on the Reykjanes Peninsula in Southwest Iceland. This choice was governed by balancing geological and environmental criteria, the drilling plans of the Icelandic energy companies, and the realities of the funding situation. The aim of deep drilling is to investigate deep geothermal resources, and more especially to explore for supercritical conditions that could produce very high power outputs from geothermal wells.
Hitaveita Sudurnesja, one of the Icelandic energy companies sponsoring the IDDP, has decided to drill and later flow test a 3 km deep well in 2004, subject to final business agreements expected in January. IDDP plans to deepen this well by coring to 4.2 km in 2005 and then ream the hole, preparatory to a second flow test from that depth. In 2006 the open section will be cased before a second stage of core drilling from 4.2 to 5.0 km. After inserting a liner (the “pipe”), a third flow test will be carried out from the deepest levels.
The deep well at Reykjanes will allow sampling fluids from 3000 m, 4000 m and 5000 m and produce 2000 m of core through the transition from upper to lower crust in a high-temperature hydrothermal system located in an actively forming ophiolite environment on the landward extension of the Mid-Atlantic Ridge. This will be an important contribution to global science and have clear connections to the Integrated Ocean Drilling Program. At the same time, we will gain a great deal of information about the deeper levels of hydrothermal systems and test very high enthalpy, hopefully supercritical, production of geothermal resources.
In January 2004 a proposal to fund coring in this first well will be submitted to the International Continental Scientific Drilling Program (ICDP). A meeting of the IDDP science advisory group (SAGA), with invited participants, will take place in Iceland on May 31- June 1st 2004.