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

Abstract

Plain Language Summary
Seismogenic turbidites are widely used for geohazard assessment. The use of turbidites as an earthquake indicator requires a clear demonstration that an earthquake, rather than non‐seismic factors, is the most plausible trigger. The seismic origin is normally verified either by correlating the turbidites to historic earthquakes, or by demonstrating their synchronous deposition in widely spaced, isolated depocenters. The correlated historic earthquakes could thus constrain the seismic intensities necessary for triggering turbidites. However, the historic correlation method is not applicable to prehistoric turbidites. In addition, the synchronous deposition of turbidites cannot be verified if only one deep core is drilled in a depocenter. Here, we propose a new approach to constrain the seismic origin for prehistoric turbidites in a deep core from the Dead Sea center. Moreover, we constrain the seismic intensities that triggered prehistoric turbidites by analyzing the degree of in situ deformation underlying each turbidite. In addition, we use our results to propose seven basic earthquake‐related depositional scenarios preserved in depocenters located in tectonically active regions like the Dead Sea. These techniques and findings permit a more confident geohazard assessment in the region and other similar tectonic settings by improving the completeness of a paleoseismic archive.

Full text

1. Introduction
Seismogenic turbidites are commonly used to derive information such as location, timing, intensity and re-
currence intervals of paleoearthquakes, and are thus vital for geohazard assessment (Goldfinger etal.,2003;
St-Onge etal.,2004; Gràcia etal., 2010; Polonia etal.,2013; Strasser etal., 2013; Pouderoux etal.,2014;
Ratzov etal.,2015; Moernaut etal.,2018; Hubert-Ferrari etal.,2020). However, the use of turbidites as
an earthquake indicator requires a demonstration that seismicity is the most plausible trigger, rather than
non-seismic factors such as flash floods (Talling etal.,2013; Katz etal.,2015), exceptional discharge (Clare
etal.,2016), and storm waves (Paull etal.,2018). This challenge is generally overcome by correlating turbid-
ites with historic earthquakes in a region (Gràcia etal.,2010; Moernaut etal.,2014; Polonia etal.,2016; Wil-
helm etal.,2016) or by demonstrating their synchronous deposition in widely spaced, isolated depocenters
(Goldfinger etal.,2007; Ratzov etal.,2015; Kioka etal.,2019).
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.
Plain Language Summary Seismogenic turbidites are widely used for geohazard assessment.
The use of turbidites as an earthquake indicator requires a clear demonstration that an earthquake, rather
than non-seismic factors, is the most plausible trigger. The seismic origin is normally verified either by
correlating the turbidites to historic earthquakes, or by demonstrating their synchronous deposition in
widely spaced, isolated depocenters. The correlated historic earthquakes could thus constrain the seismic
intensities necessary for triggering turbidites. However, the historic correlation method is not applicable
to prehistoric turbidites. In addition, the synchronous deposition of turbidites cannot be verified if only
one deep core is drilled in a depocenter. Here, we propose a new approach to constrain the seismic origin
for prehistoric turbidites in a deep core from the Dead Sea center. Moreover, we constrain the seismic
intensities that triggered prehistoric turbidites by analyzing the degree of in situ deformation underlying
each turbidite. In addition, we use our results to propose seven basic earthquake-related depositional
scenarios preserved in depocenters located in tectonically active regions like the Dead Sea. These
techniques and findings permit a more confident geohazard assessment in the region and other similar
tectonic settings by improving the completeness of a paleoseismic archive.
LU ET AL.
© 2020. The Authors.
This is an open access article under
the terms of the Creative Commons
Attribution License, which permits use,
distribution and reproduction in any
medium, provided the original work is
properly cited.
A New Approach to Constrain the Seismic Origin for
Prehistoric Turbidites as Applied to the Dead Sea Basin
Yin Lu1,2 , Jasper Moernaut2 , Revital Bookman3, Nicolas Waldmann3,
Nadav Wetzler4 , Amotz Agnon5 , Shmuel Marco6 , G. Ian Alsop7 ,
Michael Strasser2 , and Aurélia Hubert-Ferrari1
1Department of Geography, University of Liege, Liège, Belgium, 2Department of Geology, University of Innsbruck,
Innsbruck, Austria, 3Dr. Moses Strauss Department of Marine Geosciences, University of Haifa, Haifa, Israel,
4Geological Survey of Israel, Jerusalem, Israel, 5The Neev Center for Geoinfomatics, Institute of Earth Sciences,
Hebrew University of Jerusalem, Jerusalem, Israel, 6Department of Geophysics, Tel Aviv University, Tel Aviv, Israel,
7Department of Geology & Geophysics, University of Aberdeen, Scotland, UK
Key Points:
• Seismic origin for prehistoric
turbidites is established by analyzing
the underlying in situ deformation
structures for each turbidite
• Data validate a previous hypothesis
that soft-sediment deformation
formed at the sediment-water
interface in the Dead Sea
• The new approach permits a more
confident geohazard assessment by
improving the completeness of a
paleoseismic archive
Supporting Information:
• Supporting Information S1
Correspondence to:
Y. Lu,
yin.lu@uibk.ac.at;
yinlusedimentology@yeah.net
Citation:
Lu, Y., Moernaut, J., Bookman, R.,
Waldmann, N., Wetzler, N., Agnon,
A. etal. (2021). A new approach
to constrain the seismic origin for
prehistoric turbidites as applied to the
Dead Sea Basin. Geophysical Research
Letters, 48, e2020GL090947. https://doi.
org/10.1029/2020GL090947
Received 22 SEP 2020
Accepted 23 NOV 2020
10.1029/2020GL090947
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The seismic intensities required for triggering turbidites are normally constrained by the correlated earth-
quakes (Moernaut etal.,2014; Wilhelm et al., 2016). However, it is unclear whether knowledge gained
from historical turbidites is also applicable to prehistoric turbidites which are vital for recovering a long
earthquake archive. In addition, the synchronous deposition of turbidites cannot be verified if only one
deep core is drilled in a depocenter. Here, we propose a new approach to authenticate the seismic origin
and local seismic intensities for triggering prehistoric turbidites by analyzing the genetically linked in situ
deformation of each turbidite preserved in a deep core from the Dead Sea center. The observed deforma-
tions in the lake center are similar to seismically induced deformations seen in lakes from other tectonically
active regions such as California (Sims,1973), Anatolia (Avşar etal.,2016), and Southern Italy (Moretti &
Sabato,2007; Vitale etal.,2019).
2. Sedimentary Regime and Previous Lacustrine Paleoseismology Research in
the Dead Sea Basin
The sinistral strike-slip Dead Sea Fault forms the boundary between the Arabian and African plates, extend-
ing >1,000km (Ben-Avraham etal.,2008). The ∼150km long and ∼15km wide Dead Sea Basin formed
along this fault, and during the Quaternary this pull-apart basin received ∼4km of lacustrine sediments
in its depocenter (Figure1a) (Ben-Avraham etal.,2008). The sedimentary sequence comprises alternating
laminae of aragonite and detritus (aad; TextS1) (Figure1o), homogeneous mud (Figures1n and 1o), gyp-
sum (Figure1b), halite (Figure1c) (Neugebauer etal.,2014; Lu etal.,2017a, 2020a), and seismically dis-
turbed units (Figures1d–1m) (Lu etal.,2017b, 2020b). The first four types of sediment are regarded as back-
ground sedimentation (TextS2), while disturbed units including soft-sediment deformation, liquefied sand
layers, slumps, chaotic deposits, and micro-faults have been interpreted as seismites (Heifetz etal.,2005;
Ken-Tor etal.,2001; Lu etal.,2017b, 2020b; Marco & Agnon,1995; Wetzler etal.,2010).
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Figure 1. Tectonic setting of the Dead Sea Basin (a) and chemical data characterizing in situ seismites (d–m) (Lu etal.,2020b) and background deposits (b-c,
n-o) in Core 5017-1. (a) Active faults in the basin (Bartov etal.,2006; Ben-Avraham etal.,2008). (b) Gypsum. (c) Halite. (d–m) In situ seismites: (d)–(e) linear
waves (Lw); (f)–(g) asymmetric billows (Ab); (h)–(i) coherent vortices (Cv); (j)–(k) Micro-faults (Mf ); (l–m) intraclast breccias (Ib). (n–o) Background deposits;
aad, alternating laminae of aragonite and detritus; cps, count per second. See TextS3 for core depth.

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Widespread in situ soft-sediment deformation characterizes the Dead Sea sediments (Marco & Agnon,1995;
Lu etal., 2017b; Alsop etal.,2019), which manifests as several forms of (i) linear waves, (ii) asymmetric
billows, (iii) coherent vortices, and (iv) intraclast breccias (Figures1d–1m) (Lu etal.,2020b). The temporal
correspondence of these structures with historic earthquakes (Ken-Tor etal.,2001; Migowski etal., 2004)
and their juxtaposition against syn-depositional faults (Marco & Agnon,1995) reveal that these deforma-
tions are seismites. In this study, we use in situ soft-sediment deformations and micro-faults to constrain the
seismic origin and intensities of each overlying prehistoric turbidite. We also establish seven basic earth-
quake-related depositional scenarios for the lake depocenter.
3. Materials and Methods
The 457 m-long ICDP Core 5017-1 provides a record back to 220 ka (Goldstein etal., 2020) (TextS4). The
surface of the archived half of the core was scanned with the ITRAX core scanner at a resolution of 1mm, an
exposure time of 1s, and a Chromium tube at 30kV voltage and 30mA current at the GFZ (Potsdam) (Neuge-
bauer etal.,2014). This X-ray fluorescence (XRF) core scanning highlights relative element intensities which
can then be used to reveal sedimentary processes, although the absolute values could be influenced by down-
core changes in physical properties such as grain size and water content (Neugebauer etal.,2016).
In Core 5017-1, gypsum has a high content of Ca and an extremely low Ti content (Figure1b), while halite
has extremely low concentrations of both Ca and Ti (Figure1c). Detrital mud has a high content of Ti but
low Ca content, while the aragonite laminae have a low content of Ti but high content of Ca (Figures1n–
1o). These features suggest that Ca best characterizes carbonate or gypsum, while Ti best reflects the input
of exogenous clastics from the surrounding drainage basin. In addition, Ca and Ti both have sufficient count
rates and were therefore chosen to characterize sediment layers, rather than transforming the elemental
intensities into ratios or log-ratios (Weltje etal.,2015).
4. Results and Discussion
4.1. XRF Data Characterizes In Situ Seismites
Layers comprising linear waves, asymmetric billows, and coherent vortices (Figures1d–1i) have similar var-
iations of Ca and Ti to aad (Figure1o). This indicates that no external sediments were incorporated during
deformation as this would lead to significant variations in Ca and Ti. This relationship also confirms the in
situ formation and preservation processes of these units. As micro-faults only displace sediments over short
distances, they would not significantly alter the chemical features (Figures1j and 1k).
The intraclast breccia layers consist of mixed aad fragments and relict pieces of coherent vortices in their
lower parts. Large-scale intraclast breccia layers normally comprise three units: (i) unbroken coherent vorti-
ces at the base, (ii) remaining parts of coherent vortices and aad fragments in the middle, (iii) a gray-colored
unit at the top (Figure1l). The lower unit displays similar variations of Ca and Ti to aad and is sometimes
absent in thinner intraclast breccia layers (Figure1m). The middle unit shows a low content of Ca and high
content of Ti due to the accumulation of large fragments of dark detritus laminae. Finally, the upper unit is
marked by a high concentration of Ca and low concentration of Ti, indicating a local settling process dur-
ing the final stages of brecciation. The delicate aragonite laminae were disaggregated into small particles
and would therefore settle later than the larger fragments of coherent vortices and dark detritus laminae
(the middle unit). The local mixing, sorting, and settling processes require open boundary conditions and
a fluid environment at the sediment-water interface and cannot form beneath the sediment surface. These
characters therefore validate the previous basic hypothesis that intraclast breccia layers formed at the sed-
iment-water interface (Marco & Agnon,1995). Chemical features of these units differ from homogeneous
mud generated by floods (Figures1n–1o), and thus confirm the in situ formation and preservation of intr-
aclast breccia layers.
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4.2. Establishing the Seismic Origin for Prehistoric Turbidites
We recorded >700 turbidites in the entire Core 5017-1 that are classified into three categories labeled 1–3:
(1) sandy turbidites (N=9) that temporally correlate with historic earthquakes (Lu etal.,2020b); (2) tur-
bidites (N=136) that overlie in situ seismites; (3) the remaining turbidites (N>560) that lack underlying
in situ seismites. The category 3 turbidites may be triggered either by earthquakes, or by non-seismic factors
such as flooding, sediment overloading, and slope failures induced by changes in lake-levels. This study is
focused on the category two turbidites and examines the possible links between turbidites and underlying in
situ seismites. This allows us to then apply new insights into the category three turbidites, and thereby im-
prove the completeness of the paleoseismic archive in the Dead Sea. We classify the category two turbidites
into two basic types that are distinguished by distinct textures and geochemistry.
4.2.1. Type I: Sandy Turbidites
These turbidites are marked by a sandy base and usually show graded-bedding. Analysis from the base to-
ward the top of individual turbidites reveals that some display only small variations in Ca and Ti (Figure2f),
some show a decrease of Ca and an increase of Ti (Figures2g, 2k, and 2n), while others are marked by an
increase of Ca but a decrease of Ti (Figures2l and 2p). Other turbidites may display a decrease in both Ca
and Ti at the base, and an increase of both Ca and Ti in the middle and upper parts (Figures2c–2e and
2o). However, the Ti content of these turbidites is notably lower than homogeneous mud thereby making
non-seismic causes such as flooding unlikely triggers for these turbidites (Figure3b).
We find 33, 12, 15, 7, and 29 such turbidites immediately overlying layers containing linear waves, asym-
metric billows, coherent vortices, intraclast breccia, and micro-fault, respectively, with no intervening back-
ground sediment preserved between the turbidite and deformed horizon (Figure2; FigureS1). We infer that
no depositional hiatus occurred directly beneath the turbidite as the drilling site is continuously below lake
water levels. In detail, the drilling site was located in the abyssal plain of the lake depocenter with negligi-
ble slope gradients, and ∼5km from the nearest basin slopes (Lu etal.,2017b). This unique depositional
environment does not favor strong erosion by turbidity flows above the in situ seismites (FigureS2). In such
a tectonically active graben, this special combination of sediment layers makes seismic shaking the most
plausible trigger for these turbidites. We therefore propose that these sandy turbidites are genetically linked
to the underlying in situ seismites, and resulted from earthquake-triggered remobilization of nearshore
surficial sediments.
The absence of background sediments between in situ deformation structures and overlying turbidites con-
firms the linkage between these features and highlights that deformation ocurred at the interface of water
and sediments. These seismogenic turbidites appear to have no uniform chemical features, but show more
variation in Ca and Ti than homogeneous mud (Figure1n–1o), potentially indicating variability in the
source material. In addition, some turbidite layers (Figures2a–2c, 2k, and 2l) display amalgamated struc-
ture (Van Daele etal.,2017), that is, the superposition of different turbiditic flows typically triggered by an
earthquake, which may also lead to non-uniform chemical features.
4.2.2. Type II: Laminae Fragments-Embedded Detritus Layers
Gray color and sparse aad fragments characterize these layers (Figure4; FigureS3). The lack of relict frag-
ments of coherent vortices in the lower part of the layers differentiates them from the intraclast breccia
layers. The small size of fragments indicates that the aad have undergone significant transportation by
high-density turbiditic flows instead of an in situ deformation process. Type II layers from the lake margin
retain fragments of aragonite laminae (Figures4a–4c; Migowski et al., 2004) that are much larger than
those preserved in the lake center, which is consistent with significantly shorter transportation. The Type II
layers from the lake center have high concentration of Ca and low concentration of Ti, with overall values
similar to aragonite laminae (Figures4d–4m and 3b) and the upper gray-colored units of intraclast breccia
layers (Figures 1l and 1m). We interpret this to indicate a mixing process during mass transport. The upper
parts of some Type II layers are commonly lighter in color and have a higher concentration of Ca, suggesting
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that delicate aragonite laminae were broken into small particles not visible to the naked eye. In contrast,
fragments of more robust (due to their cohesively and higher density) dark detrital laminae are much better
preserved and comprise the lower parts of layers which display low Ca and high Ti (Figures4f, 4j, and 4l).
Along the Dead Sea margin (Ein Gedi core; Figure1a), such layers have been temporally correlated with
historic earthquakes (Figures4a–4c) (Agnon etal.,2006; Migowski etal.,2004). In Core 5017-1, we find 11,
2, 14, 3 and 10 such turbidites overlying layers of linear waves, asymmetric billows, coherent vortices, intr-
aclast breccia, and micro-fault, respectively (Figures4d–4m), implying a seismic origin of these sediments.
We propose that Type II layers have resulted from seismogenic slope failure-induced breakage, fluidization,
and suspension of aad fragments.
The lack of coarse clastic grains combined with the high concentrations of Ca and low concentrations of
Ti suggest that Type II layers are most probably sourced from deeper subaqueous slopes rather than the
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Figure 2. XRF data characterizing Type I turbidites from the Dead Sea center. (a–l) Turbidites (brown color) overlie in situ soft-sediment deformations (pink
color). (m–r) Turbidites overlying micro-faults. See TextS5 for core depth.

Geophysical Research Letters
nearshore region. These chemical and physical features differentiate Type II layers from any hyperpycnal
flow deposits generated by flash floods, which lack laminae fragments and have low concentrations of Ca
but high concentrations of Ti (Figures1n–1o and 3b). Therefore, we infer that the remaining turbidites with
similar textures and chemical features to the Type II layers, but lacking underlying in situ seismites (∼178 of
the category 3 turbidites), were also the product of seismogenic subaqueous slope failures (Figures4l–4p).
4.3. Constraining the Seismic Intensities that Triggered Individual Prehistoric Turbidites
A series of fluid dynamic numerical models, based on the Kelvin-Helmholtz Instability, have been con-
ducted to simulate the soft-sediment deformation processes (Heifetz etal.,2005; Lu etal.,2020b; Wetzler
etal.,2010). This modeling indicates minimum ground accelerations of 0.13g, 0.18g, 0.34g, and 0.50g are
needed to initiate linear waves, asymmetric billows, coherent vortices, and intraclast breccia with a certain
thickness, respectively (Lu etal.,2020b). These accelerations are converted into Modified Mercalli Intensity
(MMI) Scale of VI½, VII, VIII, and VIII½, respectively, via empirical relationships between MMI and peak
ground acceleration for a transform boundary setting (Lu etal.,2020b; Wald etal.,1999).
The in situ soft-sediment deformations that underly 67 Type I and 30 Type II layers constrain the local
seismic intensities that triggered these prehistoric turbidites as varying from MMI of ∼≥VI½ to>VIII½
(Figures2 and 4; Lu etal.,2020b). Thus, the dataset suggests an intensity threshold of MMI VI½ for trigger-
ing centimeter-scale prehistoric turbidites preserved in the Dead Sea center. Previous studies have revealed
that the intensity threshold for triggering historic turbidites are variable in different regions and range from
MMI V½ to VII½ (Howarth etal.,2014; Moernaut,2020; Van Daele etal.,2015; Wilhelm etal.,2016). The
intensity threshold constrained from the Dead Sea data (∼≥VI½) is situated in the middle of this range.
Previous studies in Chilean lakes have indicated that the (cumulative) thickness of historic turbidites across
multiple cores correlates with seismic intensity, and can thus be used to infer paleo-intensities in this setting
(Moernaut etal.,2014). However, in the case of the Dead Sea core 5017-1, there is a random relationship (a
correlation factor of 0.04) between the thickness of prehistoric turbidites and seismic intensity (Figure5a).
Each type of in situ deformation (representing different MMI levels) is overlain by turbidites of variable
thicknesses (Figures2 and 4). This discrepancy may be due to different conditions regarding available slope
materials affected by seismic shaking in the two different tectonic settings. Moreover, the absence of an
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Figure 3. Scatter plots of Ca and Ti for different types of sediments. (a) Relatively similar clusters of aad and deformed aad (i.e., Lw, Ab, and Cv); (b) Type I
turbidites, Type II turbidites, and homogeneous mud (generated by flash floods) from the Dead Sea center (Core 5017-1) group in distinct clusters. The aad and
homogeneous mud are background deposits; n, number of data points. Lw, linear waves; Ab, asymmetric billows; Cv, coherent vortices.

Geophysical Research Letters
intensity-thickness relationship in the Dead Sea may be caused by high-amplitude lake level fluctuations
that strongly influence the type and rate of slope sediment deposition, and by subtle micro-topography pro-
duced by each in situ deformation which modulates turbidite deposition. Therefore, caution is needed when
applying turbidite thicknesses to reconstruct paleo-intensities in different geological settings.
4.4. Models of Earthquake-Related Deposition and Paleoseismic Implications
Based on studies from the Dead Sea, we propose seven basic earthquake-related depositional scenarios in a
lake depocenter (Figures5b and 5c). Each scenario represents a single seismic event. Scenario I, an in situ
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Figure 4. XRF data characterizing Type II turbidites (the laminae fragments-embedded detritus layers) from the lake center (Core 5017-1). (a–c) The layers
from the lake margin (Ein Gedi core) that correlate with historic earthquakes (Agnon etal.,2006; Migowski etal.,2004) are used for comparison. (d–k) The
layers from the lake center (brown color) are overlying in situ seismites. (l–p) The layers from the lake center without underlying in situ seismites. The red
arrows indicate the remaining parts of Cv; the magenta circles are magnifying glasses (2.5X). See TextS6 for core depth.

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seismite overlying undisturbed sediments. This situation is recorded from the lake margin and has been
used to reconstruct the earthquake history of the Dead Sea Fault over the last 70 kyr (Ken-Tor etal.,2001;
Marco etal.,1996; Migowski etal.,2004). Moreover, based on numerical simulation of the in situ deforma-
tion processes and its application to Core 5017-1, Lu etal.(2020b) revealed and quantified the history of
large earthquakes along the central Dead Sea Fault over the past 220 kyr.
Scenario II involves sandy turbidite overlying an in situ seismite, while scenario III encompasses Type II
turbidite overlying an in situ seismite. These two situations are helpful for a better understanding of seis-
mogenic turbiditic flows by constraining the intensity threshold for triggering turbidites. In Scenario IV, the
sandy turbidite lacks an underlying in situ seismite but is temporally correlated with a historic earthquake
(Lu etal.,2020b). Scenario V involves a Type II turbidite that lacks an underlying in situ seismite. This
scenario is observed in the Dead Sea margin and has been temporally correlated to historic earthquakes
(Agnon etal.,2006; Migowski etal.,2004). Scenarios VI and VII are slump and chaotic deposits without
underlying in situ seismites, respectively (Lu etal.,2017b).
Among the models, in situ seismites are missing in scenarios IV, V, VI, and VII. We find sharp erosive bases
for scenarios VI and VII, and less distinct erosive bases for some of scenarios II-V (FigureS2). We infer that
in scenarios VI and VII, any in situ seismites, which would be positioned below the seismogenic deposits,
have been eroded by the earthquake-induced energetic mass movements. While, in scenarios IV and V, the
lack of in situ seismites is either due to their formation not being favored by the lithology or due to poor
preservation of the deformation structures. The seismogenic sediment layers in scenarios IV, V, VI, and VII
could be used as independent earthquake indicators, and are thus vital for complete paleoseismic recon-
structions in the region and similar tectonic settings elsewhere.
5. Conclusions
We constrain seismic origin of two types of turbidites by analyzing their underlying in situ seismites, then
apply the new insights into some turbidites that lack underlying in situ seismites, and thereby improve the
completeness of the paleoseismic archive in the Dead Sea. In addition, we propose seven basic post-seis-
mic depositional scenarios in a lake depocenter that is located in a tectonically active region like the Dead
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Figure 5. Seismogenic sedimentary processes and deposition models in the Dead Sea. (a) Random relationship between the thickness of prehistoric turbidites
and seismic intensity. (b) Schematic model showing co-seismic sedimentary processes in the lake. (c) Earthquake-related deposition models in the lake
depocenter. See the text for a detailed interpretation.

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Sea. These techniques and findings are vital for more complete paleoseismic reconstructions, and greater
confidence in assessing geohazards in tectonically active regions like the Dead Sea. Moreover, our high-res-
olution chemical and sedimentological data validate a previous hypothesis that soft-sediment deformation
in the Dead Sea formed at the sediment-water interface.
Data Availability Statement
Data are available in the PANGAEA database (https://doi.pangaea.de/10.1594/PANGAEA.921987).
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Acknowledgments
The authors appreciate the editor Lucy
Flesch for handling our manuscript,
Stefano Vitale and Alina Polonia for
constructive reviews. This research was
supported by the University of Liege
under Special Funds for Research,
IPD-STEMA Program (R.DIVE.0899-
J-F-G to Y. Lu), Austrian Science Fund
(FWF: M 2817 to Y. Lu), the DESERVE
Virtual Institute of the Helmholtz
Association (to A. Agnon), the Israel
Science Foundation (#1093/10 to
R.Bookman and #1645/19 to S.Marco),
and the ICDP.

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