The Tectonic Setting of Bamiyan and Seismicity in and Near Afghanistan for the Past Twelve Centuries

Abstract

The ancient city of Bamiyan is located on the Herat fault, a 1,200-km-long, east--west suture through central Afghanistan, that trends northward into the Hindu Kush mountains north of Kabul at its eastern end. The Bamiyan region is located in the transition zone between the intense seismic activity that characterises the Indo-Asian plate boundary in eastern Afghanistan, and the largely inactive central part of Afghanistan. We describe 52 earthquakes that occurred in the period A.D. 734--2004. Data for some centuries are unavailable, and only after the mid-nineteenth century does the earthquake record become more complete. Historically, the western Herat fault has remained largely inactive; however, a significant earthquake occurred near Bamiyan in 1956. The causal fault that slipped in this M = 7.4 earthquake is not known, although it appears to have occurred in the region bounded by the Herat fault and the Andarabad fault, 80 km to the north of Bamiyan.