Orbital‐ and Millennial‐Scale Changes in Lake‐Levels Facilitate Earthquake‐Triggered Mass Failures in the Dead Sea Basin

Shmuel Marco,G Ian Alsop,Michael Strasser,Revital Bookman,Amotz Agnon,Nicolas Waldmann,Yin Lu,Aurélia Hubert‐Ferrari,Jasper Moernaut

doi:10.1029/2021gl093391

Abstract

AbstractThe possible link between the occurrence of submarine mass failure and climate‐driven factors is highly disputed. This is due largely to the lack of comprehensive records of mass failures in the geologic record for which ages, triggers, and preconditioning factors can be reliably constrained. Such controls would allow accurate testing of cause‐and‐effect relationships. We present a record that comprises 490 earthquake‐triggered mass failure deposits from the Dead Sea depocenter over the past 220 kyr that permits a robust statistical evaluation and correlation with potential preconditioning factors. Our data set reveals that (a) at the orbital‐ and millennial‐scale, variable sedimentation rates are not a preconditioning factor for these mass failure deposits; (b) at the centennial‐to decadal‐scale, earthquake‐triggered mass failures can occur at any lake‐level state; (c) at the orbital‐ and millennial‐scale, the mass failures are more frequent when lake‐levels were high and punctuated by large‐amplitude fluctuations.

Highlights

Subaqueous mass failures that propagate as slides, slumps, debris flows, and turbiditic flows are major processes that transport sediments from the continental shelf and upper slope to deep basins that can have serious socioeconomic consequences (Hampton et al, 1996; Pope et al, 2017; Sammartini et al, 2019; Talling et al, 2014)
We find that sedimentation rate is not a preconditioning factor for mass failures under seismic shaking at both the orbital- and millennial-scales
To compare the probability density of seismogenic mass failure deposits with lake center and margin sedimentation rates, we group our data set of sedimentation rates and the events in 5 kyr bins

Summary

Introduction

Subaqueous mass failures that propagate as slides, slumps, debris flows, and turbiditic flows are major processes that transport sediments from the continental shelf and upper slope to deep basins that can have serious socioeconomic consequences (Hampton et al, 1996; Pope et al, 2017; Sammartini et al, 2019; Talling et al, 2014). Some researchers have documented no clear correlation between mass failure occurrence and sea-level change as the ages of failure events appear to be random (Pope et al, 2015; Urlaub et al, 2013) They suggested that an accurately dated record of subaqueous mass failure deposits from a specific setting. The slope morphology of the basin (Sade et al, 2014) and sedimentary processes at the lake margin (Alsop et al, 2016; Haliva-Cohen et al, 2012) and center (Lu, Waldmann, Ian Alsop, & Marco, 2017; Neugebauer et al, 2014) are well-understood This unique record allows a critical assessment and testing of the links between the occurrence of mass failure, changes in water-level, and sedimentation rate driven by a changing climate

Mass Failure Deposits in the Dead Sea

Results

Lake Margin and Center Sedimentation Rates Over the Last 220 kyr

Occurrence of Events in the Past Glacial-Interglacial Cycles

Discussion

Implications of the Link Between Sedimentation Rates and Occurrence of Events

Effect of Lake-Level Change on the Occurrence of Events