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Table 1 Details of the geological and geophysical data sets available for the granitic basement of the GRT-1 and GRT-2 wells

From: How do the geological and geophysical signatures of permeable fractures in granitic basement evolve after long periods of natural circulation? Insights from the Rittershoffen geothermal wells (France)

  Name Depth (MD) GRT-1 Depth (MD) GRT-2 Unit Vertical resolution–Horizontal resolution
Mud logs Cuttings 2215–2580 m, 122 samples 2480–3196 m, 239 samples No unit Sampled each 3 m in-depth
CEC No CEC measurements in GRT-1 2503–3151 m, 8 samples meq/100 g CEC measurements were performed on crushed cutting samples
Calcite 2215–2580 m 2480–3196 m m3/m3 (expressed in %) Calcimeter measurements were performed on crushed cutting samples
Mud losses 2215–2580 m 2480–3196 m m3/h Driller observations
Rate of penetration (ROP) 2215–2580 m 2480–3196 m m/h 50 cm
Geophysical logs Gamma ray (GR) 2215–2570 m 2480–3196 m gAPI 15 cm
Hole diameter 2215–2580 m 2480–3008 m Inches 15 cm 60°
BoreHole image 2480–2865 m 2480–2865 m   1 cm
Resistivity No resistivity log in GRT-1 2480–3196 m ohm m 15 cm
Porosity 2215–2577 m 2480–3196 m m3/m3 15 cm depth of investigation: several cm (flushed zone)
Density 2215–2580 m 2480–3196 m g/cm 15 cm
Temperature 2215–2470 m 2480–3169 m  °C GRT-1 = 20 cm GRT-2 = 50 cm
  1. The first column presents the type of data; columns two and three present the measured depth intervals in the two open-hole sections. The fourth column presents the units of the data, and the fifth column presents the resolution of the data according to the log acquisition resolution, both vertically and horizontally (in italic letters)