Abstract: (12334 Views)
Makran Subduction Zone (MSZ) offshore of Iran and Pakistan is one of the most
tsunamigenic sources in the Indian Ocean. Historically, the MSZ has generated some tsunamigenic
earthquakes like that of 28 November 1945 with the death tool of more than 4000 people along the
coasts of Iran, Pakistan, India, and Oman. In this study, the tsunami hazard associated with the
MSZ is investigated. At first, a review of historical tsunamis in the Indian Ocean basin was
performed which reveals the Makran region has experienced al least 4 tsunamis including events of
326 BC, 1897, 1008, and 1945. Consequently, since the pattern and extent of vertical ground
deformation from an earthquake determines whether or not a tsunami is formed, a computer
program is developed to predict the seafloor deformation due to the earthquake occurrence in the
MSZ. The model was verified through run of it on some actual tsunamis so far occurred. Then, using
the data of the 1945 Makran tsunami, the seismic parameters of the MSZ were calibrated. Finally,
we used the developed computer program to calculate seafloor deformation at the location of
Makran subduction zone for several earthquake scenarios with moment magnitudes ranging
between 6.5 and 8.5. The results of this research show that the risk of tsunami generation from MSZ
can be classified into three main categories, as follows: (1) very little risk for tsunami generation
in the case of the occurrence of an earthquake having magnitude up to 7 (2) little to medium risk
for moment magnitudes ranging between 7 and 7.5 and (3) high risk for moment magnitude greater
than 7.5. At the end of the paper, modeling of tsunami propagation is performed for an earthquake
scenario with magnitude of 8 offshore Chabahar, in order to give preliminary information about
tsunami behavior in this region.
Type of Study:
Research Paper |