Abstract
The Yerevan fault is an inferred active blind fault that extends along the northeastern margin of the Ararat Basin, although there has been no definitive evidence for its active faulting. The fault is considered as an important structure for the seismic hazard assessment of Armenia, since it extends near Yerevan City, the capital of Armenia. Our tectonic-geomorphic mapping reveals that the Vedi fault, an ~ 3 km-long fault that appears to be branched from the Yerevan fault, is an emergent active structure. The trench investigation and radiocarbon dating at Nor Ughi confirm its recent activity and suggest that the Vedi fault may have ruptured during the AD 893 Dvin earthquake, the epicenter of which is inferred to be on the southeast of Yerevan City. Judging from the geographic relationship between the Vedi and Yerevan faults, it seems likely that the main seismic source of the Dvin earthquake was the Yerevan fault, with the Vedi fault rupture being a minor branched slip.
