How Do Secondary Minerals in Granite Help Distinguish Paleo- from Present-Day Permeable Fracture Zones? Joint Interpretation of SWIR Spectroscopy and Geophysical Logs in the Geothermal Wells of Northern Alsace

<div>(a) Example of an absorption spectrum and a simulated profile in the GRT-2 well at 2800 m. (b) Reference spectra from Pontual et al. [<a href="/journals/geofluids/2019/8231816/#B52">52</a>] for biotite (Bt), muscovite (Ms), chlorite (Chl), and illite (Ilt).</div>

Geofluids

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Figure 4

Figure 4: How Do Secondary Minerals in Granite Help Distinguish Paleo- from Present-Day Permeable Fracture Zones? Joint Interpretation of SWIR Spectroscopy and Geophysical Logs in the Geothermal Wells of Northern Alsace 

Figure 4 | How Do Secondary Minerals in Granite Help Distinguish Paleo- from Present-Day Permeable Fracture Zones? Joint Interpretation of SWIR Spectroscopy and Geophysical Logs in the Geothermal Wells of Northern Alsace 