Geology Reference
In-Depth Information
crustal rocks, some of the material responds to the pull by slipping to one side or the
other. This process creates a zig-zag pattern of transform boundaries all along the diver-
gent ridge, as illustrated in Figure 9-8.
Figure 9-8:
Frac-
ture zone trans-
form faulting
across a mid-
ocean divergent
boundary.
Shaping Topography with Plate Move-
ments
The movement of crustal plates around earth's surface creates immense amounts of
pressure and strain on the solid rocks that comprise the lithosphere. These forces
stretch, bend, snap, fold, fracture, and crumple the thick, solid layers of rock on earth's
surface. In response to these kinds of physical stress, rocks
deform
or change shape.
In this section, I describe the different ways rock is deformed at plate boundaries and
how the shifting of crustal plates, combined with deformation, results in the extreme to-
pography of mountains.
Deforming the crust at plate boundaries
Because the relative motion at the different plate boundaries (convergent, divergent,
transform) is different, the rocks at each plate boundary type are deformed in different
ways.
