The simplest kind of fault
When rocks tear and break they can do so in a variety of ways, depending on whether they are being pulled apart (aka extension to geologists), pushed together (compression) or slid alongside each other (strike slip, like the San Andreas) by the tectonic forces affecting the area. This example is a normal fault from Iran, produced by pull apart forces, at least on a local level. The layers pick out very well the block of rock that has dropped between two others, and the two fault lines bordering it. The tectonics in Iran are complex, the main forces are compressive as Arabia separates from Africa and is in a slow motion collision that is closing the Persian Gulf. As the rock is pushed out of the way and uplifted to form mountains such as the Zagros range some regions are twisting and buckling in a rotatory motion, leading to local extensive forces and normal faulting.
Loz
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