OSL dating of landslide-dammed-lake deposits in the North of Tehran, Iran: 958 Ray-Taleghan/Ruyan earthquake

Abstract One large landslide (Soleghan) in the north of the megacity, Tehran, has been surveyed for dating with OSL methods. Landslide dammed-lake deposits of the Soleghan landslide was used to obtain the age of the landslide event using the SAR protocol for both quartz and feldspar grains. The age of the event was 1.09 ± 0.09 ka for quartz, and 1.03 ± 0.08 ka and 1.10 ± 0.13 ka for feldspars (stimulation at 50 °C and 225 °C, respectively). These results suggest that the Soleghan mass movement was an earthquake-induced landslide triggered by the 23rd February 958 7.7 M Ray-Taleghan/Ruyan earthquake. Based on this work, thorough review studies of landslides using OSL dating methods can be used to determine the age of other mass movements in Iran. Multiple landslides with identical ages, which may be attributed to a seismic event, could be created by a known earthquake or an unknown earthquake. Subsequently, finding an unknown earthquake will complete the earthquake catalogue resulting in a better hazard assessment.