Page 254 - Global Tectonics

240 CHAPTER 8

X 3 X 3 X 3
(a) (b) (c)

0 0 0
Upper crust Upper crust Upper crust
20 Lower crust 20 Lower crust 20 Lower crust
600 C 40 600 C 40 600 C
Depth, km 60 900 C Depth, km 60 900 C Depth, km 60 Mantle 900 C
40
80 Mantle 80 Mantle 80
1200 1200 C
1200 C
100 100 100
100 50 0 100 50 0 100 50 0
Distance, km Distance, km Distance, km
1 1 1
Strength 0.8 Strength 0.8 Strength 0.8
0.6
0.6
0.6
100 50 0 50 100 50 0 50 100 50 0 50
Distance, km Distance, km Distance, km
Time: 0.2 Myr Time: 0.2 Myr Time: 2.0 Myr
0 0 0
20 20 20
Depth, km 40 Depth, km 40 Depth, km 40
60
60
60
80 80 80
100 100 100
100 50 0 100 50 0 100 50 0
Distance, km Distance, km Distance, km
Time: 2.6 Myr Time: 2.6 Myr Time: 4.0 Myr
0 0 0
20 20 20
Depth, km 40 Depth, km 40 Depth, km 40
60
60
60
80 80 80
100 100 100
100 50 0 100 50 0 100 50 0
Distance, km Distance, km Distance, km
Log (strain rate)
16 15 14 13
Figure 8.21 Thermomechanical models of simple strike-slip faulting in a three-layer lithosphere that incorporate
initial variations in (a) crustal thickness, (b) lithospheric temperature, and (c) both crustal thickness and lithospheric
temperature (after Sobolev et al., 2005, with permission from Elsevier). Top row of diagrams shows model setup
geometry with corresponding lithospheric strength curves before deformation below them. Thin black lines are
isotherms prior to deformation. Lower two rows of diagrams show snapshots of the distribution of strain rate
demonstrating the strain localization process.