Analysis of fractures in boreholes of the Hot Dry Rock project at Soultz-sous-Forêts (Rhine graben, France)
Résumé
The Hot Dry Rock (HDR) geothermal drill site is located in the Upper Rhine Graben at Soults-sous-Forêts (Alsace, France). Two boreholes reach a highly fractured basement of porphyritic granite, potential site for a geothermal reservoir. Data from the striated faults observed on cores enabled us to compute the palestress tensors correspondng to the tectonic regimes that affected the granite. Four stress states have thus been determined: a N20°E compression , an N100°E extension, a N80°E compression ans a N120°E compression. Both naturaland induced fractures were recognised in cores. The mean strike of natural fractures changes progressively with depth from N170°E to N200°E. Theses fractures from conjugate systems and their dip direction
Domaines
Sciences de la TerreOrigine | Fichiers produits par l'(les) auteur(s) |
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