Calibrating a new attenuation curve for the Dead Sea region using surface wave dispersion surveys in sites damaged by the 1927 Jericho earthquake

Abstract

Abstract. Instrumental strong motion data are not common around the Dead Sea region. Therefore, calibrating a new attenuation equation is a considerable challenge. However, the Holy Land has a remarkable historical archive, attesting to numerous regional and local earthquakes. Combining the historical record with new seismic measurements will improve the regional equation. On 11 July 1927, a rupture, in the crust in proximity to the northern Dead Sea, generated a moderate 6.2 ML earthquake. Up to 500 people were killed, and extensive destruction was recorded, even as far as 150 km from the focus. We consider local near-surface properties, in particular, the shear-wave velocity, as an amplification factor. Where the shear-wave velocity is low, the seismic intensity far from the focus would likely be greater than expected from a standard attenuation curve. In this work, we used the multichannel analysis of surface waves (MASW) method to estimate seismic wave velocity at anomalous sites in Israel in order to calibrate a new attenuation equation for the Dead Sea region. Our new attenuation equation contains a term which quantifies only lithological effects, while factors such as building quality, foundation depth, topography, earthquake directivity, type of fault, etc. remain out of our scope. Nonetheless, about 60 % of the measured anomalous sites fit expectations; therefore, this new ground-motion prediction equation (GMPE) is statistically better than the old ones. From our local point of view, this is the first time that integration of the 1927 historical data and modern shear-wave velocity profile measurements improved the attenuation equation (sometimes referred to as the attenuation relation) for the Dead Sea region. In the wider context, regions of low-to-moderate seismicity should use macroseismic earthquake data, together with modern measurements, in order to better estimate the peak ground acceleration or the seismic intensities to be caused by future earthquakes. This integration will conceivably lead to a better mitigation of damage from future earthquakes and should improve maps of seismic hazard.

A 220,000-year-long continuous large earthquake record on a slow-slipping plate boundary

“…We applied all these three empirical attenuation relations (28,30,31) to constrain the lower magnitude limit of paleoseismic events recorded in the ICDP Core 5017-1. The attenuation relation of Malkawi and Fahmi (28) is more suitable for the inverting point intensity of strong seismic shaking events (MMI ≥ IX) to magnitude than the others.…”

Earthquake damage as a catalyst to abandonment of a Middle Bronze Age settlement: Tel Kabri, Israel

“…Analysis of these earthquakes over the years has led to the conclusion that they can cause significant damage far from the main fault trace (e.g. [21,37,38]).…”

“…Red dot marks the location of Tel Kabri. Reprinted from [ 21 ] under a CC BY license, with permission from [Copernicus Publications], original copyright [2019]. (b) Compiled map of faults in the Galilee area.…”

Two Inferred Antique Earthquake Phases Recorded in the Roman Theater of Beit-Ras/Capitolias (Jordan)

“…This is based on historical documentation and the main historical earthquake catalogues of the DST region, and estimating plausible seismic intensities (MMI). For these events, seismic intensities (MMI) were estimated based on a new attenuation equation developed for the Dead Sea region (Hough and Avni, 2009), taking into consideration site amplification conditions (Darvasi and Agnon, 2019).…”

“…Further in-depth historical studies are needed to recover information about them. In order to discuss potential causative relationships to candidate earthquakes, where observed earthquake archaeological effects (EAEs) produced a minimum seismic intensity of VIII-IX in the theater, an attempt was made to constrain the candidate events based on expected earthquake MMI intensities using a calibrated intensity-based attenuation model of the Dead Sea as proposed by (Hough and Avni, 2009) and developed by Darvasi and Agnon (2019) to incorporate site specific conditions (equation 1). The model incorporated site specific conditions (i.e.…”