reservoir geomecanics

t/S v
−1
.8
.6
.4
.2
0
0
1.5 2
1.5 2
(s n - P p )/S v
−0.5 0 0.5 1 1.5 2 −1 −0.5 0 0.5 1
-1 -0.5 0 0.5 1
(σ n - P p )/S v (s n - P p )/S v
CFF/S v
P p/S v
CFF/S v P p/S v
CFF/S v
P p/S v
.8
.8
.6
.6
.4
.4
.2
.2
.5 1 1.5 2
0
0 .5 1 1.5 2
0
0 .5 1 1.5 2
t/S v
t/S v
Figure 11.5. Faults identified in image logs from wells A, B, C in the Monterey formation of western
California shown previously in Figure 5.8. As in Figure 11.4, the color of the stereonets indicates the
tendency for fault slip to occur for a fault of given orientation, in terms of either the CFF or pore pressure
needed to induce fault slip. Critically stressed faults are shown in white on the stereonet and red in the Mohr
diagram. Note that although each well is considered to be in the same reverse/strike-slip stress state, the
distribution of critically stressed faults in each well is quite different because of the distribution of faults that
happen to be present in the three respective wells.