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Table 1 Faults observed on the seismic profile analysed in mud logging and log cutting

From: New stratigraphic interpretation of the Soultz-sous-Forêts 30-year-old geothermal wells calibrated on the recent one from Rittershoffen (Upper Rhine Graben, France)

Depth
 ~300 m GPK-1
Very local fault with almost no apparent fault offset
Mud logging: nothing observed
Log cutting: nothing observed
 ~750 m Local fault from the surface to the Kutzenhausen boundary fault which has a 100 m fault offset
Mud logging: caliper and temperature anomalies
Log cutting: nothing observed
 ~1083 m Soultz-sous-Forêts Fault from the surface down into the granitic basement with approximately 100 m cumulated fault offset
Mud logging: between 1042 and 1049 m several caliper anomalies, variations in neutron porosity, temperature and bulk density
Log cutting: Couches Intermédiaires reduced about 29.5 m in comparison with Rittershoffen
 ~1116 m Mud logging: nothing observed
Log cutting: nothing observed
 ~1233 m Mud logging: anomalies in temperature and ROP, and between 1219 and 1240 m total mud losses which involves a permeable fault at 1219 m
Log cutting: anhydrites filling, Couches de Rehberg twice reduced in comparison with Rittershoffen (33 m instead of 79.5 m)
 ~1316 m Mud logging: nothing observed
Log cutting: nothing observed
  GPK-2
 ~266 m Local fault from the surface to the Kutzenhausen boundary Fault with 100 m fault offset
Mud logging: nothing observed
Log cutting: a fault with a small vertical offset in an unconsolidated unit (Couches de Pechelbronn) is not necessary visible, moreover it is the uppermost unit therefore already eroded at the top
 ~708 m Soultz-sous-Forêts Fault from the surface down into the granitic basement with approximately 330 m cumulated fault offset
Mud logging: little gas peak
Log cutting: nothing observed
 ~733 m Mud logging: nothing observed
Log cutting: nothing observed
 ~766 m Mud logging: nothing observed
Log cutting: nothing observed