relation: https://episodesplatform.eu/eprints/1852/ title: Fractures, hydrothermal alterations and permeability in the Soultz Enhanced Geothermal System creator: Ledésert, Béatrice creator: Hebert, Ronan creator: Genter, Albert creator: Bartier, Danièle creator: Clauer, Norbert creator: Grall, Céline subject: Other-additional study subject: Soultz-sous-Forets subject: Geothermal energy production description: Borehole studies of the Soultz-sous-Forêts granite are dedicated to deep geothermics. The hydraulic properties of the reservoir are mainly controlled by the occurrence of some altered cataclastic shear zones showing a low natural permeability characterized by the occurrence of brines. Those zones show a fracture cluster organisation with sealed fractures of various types (post-filled joints, sheared fractures, veins). The main hydrothermal deposits observed within the permeable zones are geodic quartz, carbonates, illite and more locally sulphides. The fracture wall–rocks are intensely transformed: dissolution of igneous minerals, crystallization of new minerals, porosity and permeability increase. It is important to characterize the newly-formed minerals in order to choose the reagents used to improve the permeability of the exchanger by chemical stimulations. This article represents a synthesis of the studies completed by the authors between 1990 and 2008 on the fracture networks, hydrothermal alterations and mineral crystallizations they induced and data about the flow pathways in the exchanger. publisher: Elsevier date: 2010 type: Article type: NonPeerReviewed identifier: Ledésert, Béatrice and Hebert, Ronan and Genter, Albert and Bartier, Danièle and Clauer, Norbert and Grall, Céline (2010) Fractures, hydrothermal alterations and permeability in the Soultz Enhanced Geothermal System. Comptes Rendus Geoscience, 342 (7-8). pp. 607-615. DOI: https://doi.org/10.1016/j.crte.2009.09.011 relation: http://doi.org/10.1016/j.crte.2009.09.011 relation: doi:10.1016/j.crte.2009.09.011