Field Survey of the 1945 Makran and 2004 Indian Ocean Tsunamis in Baluchistan, Iran

We report the result of a 2010 survey of the effects on the Iranian coastline of the tsunami which followed the earthquake of 27 November 1945 (M0 = 2.8 9 10 28 dyn cm; Mw = 8.2), the only large event recorded along the Makran subduction zone since the onset of instrumental seismology. Based on the interview of elderly survivors of the event, we obtained a database of nine values of run-up or splash amplitudes on a segment of shore extending 280 km from Souraf in the West to Pasabandar near the Pakistani border, and ranging in vertical amplitude from 2.3 to 13.7 m. Witness reports are consistent with a significant delay (estimated at *2.5 h) of the tsunami waves, suggesting that they were generated by an ancillary phenomenon, such as a landslide triggered by the earthquake. None of our witnesses bore ancestral memory of comparable events in the past, suggesting that reported predecessors to the 1945 earthquake may have been smaller in size. The survey also allowed the compilation of previously unreported data concerning the effects of the 2004 Sumatra–Andaman tsunami.