The Kopet Dag mountain range lies at the northern edge of the complex zone of deformation caused by the continuing collision of the Arabian Plate with the Eurasian Plate. To the west it links with the Caucasus Mountains through the Caspian Sea. There is currently about 3 mm per year of shortening across the Kopet Dag as a whole. The Quchan Fault zone, trending NNW-SSE, is one of a set of active right lateral strike-slip faults that accommodate part of the shortening across the Kopet Dag and extension along its length. It has an estimated displacement rate of about 1.5 mm per year. The damage areas of the sequence of earthquakes that affected the Quchan area between 1851 and 1895 follow the projected path of the Quchan fault and its likely continuation as a thrust fault in the Atrak valley, where it forms a surface anticline.