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 6

Magnified view of the four (a, b, c, and d) main permeable FZs of the GRT-2 well at Rittershoffen, presenting the mineral quantity, petrographical log, log, porosity and density logs, total GR, SWIR results with water and the 2200 nm absorption band areas, and resistivity log (low values to the right). Petrographical facies abbreviations are defined in the legend in Figure 3.