Figure 9
Stress field interpretation near the well Th1 and the stress pattern in Th2 and Th3. Gray arrows present the orientation of the maximum horizontal stress. Here, local variations of a strike-slip regime (SS) and a normal faulting regime (NF) can be observed. For well Th1, a local perturbation of the stress regime is observed and determined to be strike slip and SH oriented to 320° (Case I) or normal faulting regime with SH oriented towards the N-S (Case II). In Th2 and Th3, the strike-slip regime is observed with SH having an N-S orientation. The Rose diagram illustrates the fracture sets. The principal fracture set in Th1 for stress state Case I indicates a high shear tendency. For Case II, these fracture sets exhibit a dilatational tendency (white arrows). Fracture sets in Th2 and Th3 show a dilatational tendency (white arrows) (NNE-SSW) as well as a closing tendency (black arrows) (ENE-WSW) in the strike-slip stress regime.