M 7.2 - 104 km W of Murghob, Tajikistan

Tectonic Summary

The December 7, 2015, M 7.2 earthquake in Tajikistan occurred as the result of strike-slip faulting within the crust of the Eurasia plate. Focal mechanism solutions indicate that rupture occurred on either a northwest-southeast-striking right-lateral fault, or on a southwest-northeast-striking left-lateral fault. Of these two possible fault orientations, finite-fault modeling of globally recorded seismic data is more consistent with slip on the southwest-striking (left-lateral) fault. At the location of this earthquake, the India plate is moving northward with respect to Eurasia at a rate of approximately 38 mm/yr.

The December 7, 2015, earthquake is located several hundred kilometers north of the India:Eurasia plate boundary, in the Pamir Mountains. The collision of these two plates drives the tectonics of the broad region surrounding the Himalayan Mountains and the Tibetan Plateau, and causes uplift that produces the highest mountain peaks in the world including the Himalayan, the Karakoram, the Pamir, and the Hindu Kush Ranges.

The location of the December 7, 2015, earthquake is close to Saraz Lake, which was formed in February 1911 when a nearby M 7.3 earthquake triggered a landslide that dammed the Murghab River. Over the past century, 18 other earthquakes of M 6.5 or larger have occurred within 250 km of the December 7, 2015, earthquake. Given the remoteness of the region, earthquakes here rarely cause shaking-related fatalities; however, secondary hazards such as landsliding have caused damage and fatalities in the past.

Hayes et al. (2016) Tectonic summaries of magnitude 7 and greater earthquakes from 2000 to 2015, USGS Open-File Report 2016-1192. (5.2 MB PDF)