The September 24, 2013 M7.7 earthquake in south-central Pakistan occurred
as the result of oblique-strike-slip type motion at shallow crustal depths.
The location and mechanism of the earthquake are consistent with rupture
within the Eurasia plate above the Makran subduction zone. The event occurred
within the transition zone between northward subduction of the Arabia plate
beneath the Eurasia plate and northward collision of the India plate with the
Eurasia plate. The epicenter of the event is 69km north of Awaran, Pakistan,
and 270km north of Karachi, Pakistan.
On a broad scale, the tectonics of southern and central Pakistan reflects a
complex plate boundary where the India plate slides northward relative to the
Eurasia plate in the east, and the Arabia plate subducts northward beneath the
Eurasia plate in the Makran (western Pakistan). These motions typically result
in north-south to northeast-southwest strike-slip motion at the latitude of the
September 24 earthquake that is primarily accommodated on the Chaman Fault,
with the earthquake potentially occurring on one of the southern-most strands of
this fault system. Further, more in-depth studies will be required to identify the
precise fault associated with this event.