Crustal Fault Zones (CFZ) as Geothermal Power Systems: A Preliminary 3D THM Model Constrained by a Multidisciplinary Approach

Figure 7

Facies, textures, and composition details of the Pontgibaud hydrothermal system. (a) LPA thin-section view of least altered and unfractured samples. Others (b–e) show altered and fractured facies which are much more present in the samples. (c) is a zoom of a part of (b) and shows voids present at smaller scales. (f) Crosspolar thin-section view of cataclasite. Abbreviations from Whitney and Evans, [100]: Pl: plagioclase; Bt: biotite; Qz: quartz; Ser: sericite. Other abbreviations: Cat: cataclasite; Ox: oxyde. The thin section come from samples retrieved from the Peyrouses 1 borehole, located within the Pontgibaud CFZ (see location in Figure 1).

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