caa a22 4500 528786326 20190713030956.0 cr unu---uuuuu 180924s2015 xx s 000 0 eng 10.3929/ethz-b-000103244 doi 10.1038/ncomms8837 doi (ETHRESEARCH)oai:www.research-collection.ethz.ch:20.500.11850/103244 Scott Samuel Geologic controls on supercritical geothermal resources above magmatic intrusions [Elektronische Daten] [Samuel Scott, Thomas Driesner, Philipp Weis] Nat Commun Open access ethresearch A new and economically attractive type of geothermal resource was recently discovered in the Krafla volcanic system, Iceland, consisting of supercritical water at 450 °C immediately above a 2-km deep magma body. Although utilizing such supercritical resources could multiply power production from geothermal wells, the abundance, location and size of similar resources are undefined. Here we present the first numerical simulations of supercritical geothermal resource formation, showing that they are an integral part of magma-driven geothermal systems. Potentially exploitable resources form in rocks with a brittle-ductile transition temperature higher than 450 °C, such as basalt. Water temperatures and enthalpies can exceed 400 °C and 3 MJ kg−1, depending on host rock permeability. Conventional high-enthalpy resources result from mixing of ascending supercritical and cooler surrounding water. Our models reproduce the measured thermal conditions of the resource discovered at Krafla. Similar resources may be widespread below conventional high-enthalpy geothermal systems. Creative Commons Attribution 4.0 International http://creativecommons.org/licenses/by/4.0 ethresearch Driesner Thomas joint author Weis Philipp joint author Nature Communications London : Nature Publishing Group 6, p. 7837 2041-1723 http://hdl.handle.net/20.500.11850/103244 text/html WWW-Backlink auf das Repository (Open access) 1 Journal Article ethresearch ETHRESEARCH 856 40 http://hdl.handle.net/20.500.11850/103244 text/html WWW-Backlink auf das Repository (Open access) ETHRESEARCH 100 1- Scott Samuel ETHRESEARCH 700 1- Driesner Thomas joint author ETHRESEARCH 700 1- Weis Philipp joint author ETHRESEARCH 773 0- Nature Communications London : Nature Publishing Group 6, p. 7837 2041-1723 BK010053 XK010053 XK010000 ETHRESEARCH ETHRESEARCH ETHRESEARCH Journal Article Open access