Features of seismogenic mass failure deposits in the Dead Sea center over the last 220 kyr based on the ICDP Dead Sea Core 5017-1

We investigated seismogenic mass failure deposits in the Dead Sea center over the last 220 kyr based on the ICDP Dead Sea Core 5017-1. We subdivide the seismogenic mass failure deposits into four basic types. (i) Seismogenic sandy turbidites; (ii) Laminae fragments-imbedded detritus layers; (iii) Slump deposits; (iv) Chaotic deposits. We measured the thickness and occurrence frequency of these seismogenic mass failure deposits. We applied XRF-data [ln(Ca/Ti)] and magnetic susceptibility to characterize these seismogenic mass failure deposits. Our Dead Sea case study provides a unique opportunity to distinguish and separate trigger and preconditioning factor(s) of subaqueous mass failure deposits. The record allows a statistical evaluation and correlation with potential preconditioning factors. We find that a variable sedimentation rate is not the preconditioning factor for mass failures under seismic shaking in the Dead Sea. Our dataset reveals that at the orbital- and millennial-scale, variable sedimentation rates are not a preconditioning factor for these mass failure deposits; (ii) at the centennial- to decadal-scale, earthquake-triggered mass failures can occur at any lake-level state; (iii) at the orbital- and millennial-scale, the mass failures are more frequent when lake-levels were high and punctuated by large-amplitude fluctuations.

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