OVERESTIMATION of DISPLACEMENT DUE to MISINTERPRETATION of EARTHQUAKE RUPTURE PARAMETERS

Year 2021, Issue: 047, 39 - 46, 31.12.2021

Cüneyt Yavuz

Abstract

Tsunamis that killed hundreds of thousands of people, especially in the last two decades, are one of the most devastating natural hazards. Throughout history, tsunamis caused by devastating earthquakes have resulted in the loss of life, property, and environmental damage on the coasts. Recently, however, extreme hazard possibilities have been suggested due to misinterpretation of earthquake parameters and the overestimation of displacements. The structure of the seismic moment equation commonly used by scientists allows some manipulation on the rupture area of the fault and the displacement. Because of this gap, scientists produce different displacement amounts for an earthquake of the same magnitude and therefore, different tsunami wave heights are estimated by decreasing the rupture area and also, increasing the displacement under the sea. In this study, earthquake parameters are calculated based on a comprehensive literature review and compared with previous studies. The difference between the displacements calculated using regression analysis in the study and other studies reveals that the assumptions and estimations regarding the rupture parameters differs according to expert knowledge. The article aims to shed light on a reliable method of rupture parameter calculation to avoid misinterpretation and randomness.

Keywords

Misinterpretation of rupture parameters, displacement, historical earthquakes, overestimation of tsunami wave heights

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