A New Approach to Constrain the Seismic Origin for Prehistoric Turbidites as Applied to the Dead Sea Basin

Abstract

The seismic origin of turbidites is verified either by correlating such layers to historic earthquakes, or by demonstrating their synchronous deposition in widely spaced, isolated depocenters. A historic correlation could thus constrain the seismic intensity required for triggering turbidites. However, historic calibration is not applicable to prehistoric turbidites. In addition, the synchronous deposition of turbidites is difficult to test if only one deep core is drilled in a depocenter. Here, we propose a new approach that involves analyzing the underlying in situ deformations of prehistoric turbidites, as recorded in a 457 m‐long core from the Dead Sea center, to establish their seismic origin. These in situ deformations have been verified as seismites and could thus authenticate the trigger for each overlying turbidite. Moreover, our high‐resolution chemical and sedimentological data validate a previous hypothesis that soft‐sediment deformation in the Dead Sea formed at the sediment‐water interface.

What controls the remobilization and deformation of surficial sediment by seismic shaking? Linking lacustrine slope stratigraphy to great earthquakes in South–Central Chile

“…These SSDS form directly at or close to the sediment–water interface (e.g. Sims, 1973 ; Marco & Agnon, 1995 ; Lu et al., 2021 ) making them a valuable time marker for past seismic events.…”

“…The SSDS have been linked to seismic shaking in many onshore and offshore settings – both contemporaneous and palaeo – and used to investigate palaeo‐earthquakes and unravel earthquake recurrence patterns (e.g. Marco et al., 1996 ; Becker et al., 2002 ; Monecke et al., 2004 ; Obermeier, 2009 ; Avşar et al., 2016 ; Lu et al ., 2020 ). Previous studies derived quantitative earthquake information from subaqueous sedimentary records by correlating shaking intensity with specific characteristics of lacustrine SSDS, such as thickness (e.g.…”

“…Hibsch et al., 1997 ; Rodríguez‐Pascua et al., 2003 ) or type (e.g. Sims, 1973 ; Rodríguez‐Pascua et al., 2010 ; Lu et al., 2020 ). Most of these studies focused on SSDS related to prehistorical earthquakes on outcrops of palaeo‐lakes (e.g.…”

“…Other studies are based on numerical simulations (Wetzler et al., 2010 ) – which use generic input parameters and require validation in natural settings – or identified SSDS using two‐dimensional images of a small amount of sediment cores (e.g. Monecke et al., 2004 ; Avşar et al., 2016 ; Lu et al., 2020 ) – which potentially leaves small‐scale features undetected and hinders the evaluation of spatial SSDS variability.…”

Criteria to discriminate between different models of thrust ramping in gravity-driven fold and thrust systems

“…Movement directions of MTDs have been further substantiated by analysis of Anisotropy of Magnetic Susceptibility (AMS) fabrics from within the FATS exposed along the western shore of the Dead Sea . This collective input of MTDs from around the basin margins results in greater thicknesses of sediment in the depocenter, where drilling has shown the Lisan Formation to be three times thicker than its (now) exposed marginal equivalent (Lu et al, 2017(Lu et al, , 2021Kagan et al, 2018).…”