An assessment of neotectonic activity and seismicity around the Torud fault, south of Damghan

Located at the south of Damghan and at the northern border of the Central Iran seismotectonic province, the NE-SW trending Torud fault is known as one of the major active faults of Iran. During the past century, the Torud region has been subjected to many destructive earthquakes (e.g., ۱۹۱۵, ۲۲ July ۱۹۲۷, ۱۱ April ۱۹۲۸, ۶ April ۱۹۳۹, ۱۲ February ۱۹۵۳ and ۲۷ August ۲۰۱۰). The ۱۲ Feb. ۱۹۵۳ Torud earthquake with Mw=۶.۴ was the largest recorded earthquake that occurred in this area. In this research, the seismicity and neotectonic activity of this area have been studied by analyzing earthquake catalog data of this region as well as by detailed morphotectonic study of the aerial photographs and satellite imageries of the region. For this purpose, the recorded earthquake data of the areas around the Torud fault zone was derived from national and international data catalogs and the seismicity map of the region was prepared. By analyzing this data catalog, the seismicity parameters, quantitatively showing the seismic activity behavior of the region, were estimated. Additionally, based on the detailed study of different geomorphological features, the evidences of neotectonic activities for the region were investigated. Neotectonic landforms of the area and quantitative morphotectonic indices calculated for this region demonstrate a present-day tectonic activity for the region. Finally, results obtained indicate that the areas around the Torud-Reshm fault zone show a high level of neotectonic activity and also, these areas have a high potential of occurrences of destructive earthquakes in the future.

کلیدواژه ها:

Neotectonics ، Active faulting ، Active tectonics ، Seismicity parameters ، Torud area ، Quaternary faults