The Altyn Tagh Fault is a huge left-lateral strike-slip fault about 1,600 kilometres long that forms the northern edge of the Tibetan Plateau, separating it from the Tarim Basin in northwest China. It is one of the master faults that lets crust squeezed by the India-Asia collision slide eastward, a process known as continental escape or lateral extrusion.
Slipping at roughly 10 to 20 millimetres per year, it is one of Asia's most prominent intracontinental faults and is clearly visible from space as a sharp line across the desert. Its motion helps translate the north-south crustal shortening of the Himalaya into eastward flow of the Tibetan crust.
Although it runs through sparsely populated high desert, the fault has produced large earthquakes, including events estimated near magnitude 7 to 8 in its history, and its central and western segments are considered capable of generating great ruptures that build the surrounding mountain ranges.