EGU21-617
https://doi.org/10.5194/egusphere-egu21-617
EGU General Assembly 2021
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

A 220,000-year-long continuous large earthquake record from the central Dead Sea Fault

Yin Lu1, Nadav Wetzler2, Nicolas Waldmann3, Amotz Agnon4, Glenn Biasi5, and Shmuel Marco6
Yin Lu et al.
  • 1University of Innsbruck, Institute of Geology, Sedimentary Geology Group, innsbruck 6020, Austria (yin.lu@uibk.ac.at)
  • 2Geological Survey of Israel, 32 Yeshayahu Leibowitz Street, Jerusalem 9692100, Israel.
  • 3Dr. Moses Strauss Department of Marine Geosciences, Leon H. Charney School of Marine Sciences, University of Haifa, Mount Carmel 3498838, Israel.
  • 4The Neev Center for Geoinfomatics, Institute of Earth Sciences, Hebrew University, Jerusalem 9190401, Israel
  • 5Nevada Seismological Laboratory, University of Nevada Reno, Reno, NV 89557, USA.
  • 6Department of Geophysics, Tel Aviv University, Tel Aviv 6997801, Israel.

Large earthquakes (magnitude ≥ 7.0) are rare, especially along slow-slipping plate boundaries. Lack of large earthquakes in the instrumental record enlarges uncertainty of the recurrence time; the recurrence of large earthquakes is generally determined by extrapolation according to a magnitude-frequency relation. We enhance the seismological catalog of the Dead Sea Fault Zone by including a 220,000-year-long continuous large earthquake record based on seismites from the Dead Sea center (ICDP Core 5017-1). We constrain seismic shaking intensities via computational fluid dynamics modeling and invert them for earthquake magnitude. Our analysis shows that the recurrence time of large earthquakes follows a power-law distribution, with a mean of ≤ 1400±160 years. This mean recurrence is significantly shorter than the previous estimate of 11,000 years for the past 40,000 years. Our unique record confirms a clustered earthquake recurrence pattern and a group-fault temporal clustering model, and reveals an unexpectedly high seismicity rate on a slow-slipping plate boundary.

Our results suggest that researchers may underestimate the seismic hazard potential of similar slow-slipping faults with irregular rupture. Our study highlights the potential of in situ deformed sediment layers in a subaqueous environment as a strong-motion paleo-seismometer to record long seismic sequences covering multiple recurrence intervals of large earthquakes. Long records are vital for accurate hazard assessment. Our quantitative method of seismic record reconstruction, with paleo-earthquake intensity (ground acceleration) and magnitude estimation, may also prove suitable for similar subaqueous environments along other faults.

How to cite: Lu, Y., Wetzler, N., Waldmann, N., Agnon, A., Biasi, G., and Marco, S.: A 220,000-year-long continuous large earthquake record from the central Dead Sea Fault, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-617, https://doi.org/10.5194/egusphere-egu21-617, 2021.

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