At a strike-slip fault, one plate moves laterally against another. A complicated intersection Turkey's tectonic situation is complex. Long a crossroads of people and cultures, it's also a crossroads of tectonic plates. The result is that the Anatolian plate is moving about 30 millimeters per year, relative to the Eurasian plate. The movement occurs along the North Anatolian fault that ruptured this August, and pushes the Anatolian plate counterclockwise.
Faults can move in several ways.
Lacking the relief of regular, minor earthquakes, strong rock gets stuck at the fault zone, allowing strain to build up. When the strain gets too great, it is relieved by the sudden movement of a major earthquake. The greater the strain, the larger the earthquake. Thus in a sense, earthquakes should be predictable if we know the strain and the strength of the rocks. Unfortunately, despite that simple equation, precise predictions of quakes are not possible now.