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

Area of Science:

• Geophysics
• Paleoseismology
• Tectonics

Background:

• Large earthquakes (magnitude ≥ 7.0) are infrequent, particularly along slow-slipping plate boundaries.
• Instrumental records are often too short to accurately determine the recurrence time of major seismic events.
• Estimates of earthquake recurrence typically rely on extrapolations from magnitude-frequency relations.

Purpose of the Study:

• To enhance the seismological catalog of the Dead Sea Fault Zone (DSFZ).
• To establish a long-term earthquake record to better understand recurrence patterns.
• To investigate the seismicity rate on a slow-slipping plate boundary.

Main Methods:

• Developed a 220,000-year-long earthquake record using seismites from the Dead Sea.
• Utilized computational fluid dynamics (CFD) modeling to constrain seismic shaking intensities.
• Inverted seismic intensities to determine earthquake magnitudes.

Main Results:

• Established a power-law distribution for large earthquake recurrence times.
• Calculated a mean recurrence interval of 1400 ± 160 years for large earthquakes.
• Identified a significantly shorter recurrence interval compared to previous estimates (11,000 years over the past 40,000 years).

Conclusions:

• The Dead Sea Fault Zone exhibits a clustered earthquake recurrence pattern.
• The findings support a group-fault temporal clustering model.
• Revealed an unexpectedly high seismicity rate for a slow-slipping plate boundary.