Abstract Instantaneous event deposits such as turbidites, debrites, and slumps are common and frequently occur in marginal seas. These instantaneous deposits represent seconds to days in duration, and can therefore significantly impact age‐depth models and interpretation of paleoclimate history based on thick sedimentary sequences recovered in deep drill cores. However, these event deposits have rarely been considered when investigating International Ocean Discovery Program (IODP)/ODP deep cores from marginal seas. To resolve the problem, we take the South China Sea, one of the largest active marginal seas worldwide, as a typical research example. We identified 129 centimeter‐to‐meter‐scale event layers from Hole U1433A (189–0 m, 800–0 kyr) in the southwest part of the deep South China Sea. These instantaneous event deposits account for ∼16% of the total sediment thickness in Hole U1433A, and significantly affect the reconstruction of the age‐depth model and paleoclimate history. We refine the preliminary age‐depth model, that is based on paleomagnetic and microfossil ages recovered from the hole, by removing instantaneous event deposits. We further test the effectiveness of our applied sedimentological approach by comparing paleoclimate profiles that include or omit those event layers. This test indicates that the event‐free approach is effective and essential for a better reconstruction of the age‐depth model and paleoclimate history based on the IODP deep core. Our revised sedimentological methodology may also prove suitable for other marginal seas with frequent instantaneous event deposits elsewhere in the world.
Instantaneous event deposits (e.g., turbidites and slumping layers) are common and occur frequently in the abyssal plain of marginal seas. These instantaneous deposits represent seconds to days in duration, and may significantly impact age-depth models and interpretation of paleoclimate history based on sedimentary sequences recovered in deep cores. However, these event deposits have rarely been considered when investigating IODP/ODP deep cores from marginal seas. To resolve this problem, we take the South China Sea as a typical research example, which is one of the largest active marginal seas worldwide. We apply the methodology of high-resolution event sedimentology to Hole U1433A (189-0 m, 800-0 kyr) from the SW South China Sea deep basin. We identify centimeter-to-meter-scale turbidite layers (N=129) using high-resolution NGR, GRA, magnetic susceptibility data, and core images. These instantaneous event deposits account for ~16% of the total sediment thickness in Hole U1433A. We refine the preliminary age-depth model that is based on paleomagnetic and microfossil ages recovered from the hole by removing those instantaneous event deposits. We further test the effectiveness of our revised approach by comparing paleoclimate profiles that either include or omit those event layers. This test indicates that the event-free approach is effective and essential for a better reconstruction of the age-depth model and paleoclimate history based on the IODP deep core. Our innovative sedimentological methodology may also prove suitable for other marginal seas with frequent instantaneous event deposits elsewhere in the world.
Gravity-driven sliding of sediments down subaqueous slopes results in mass transport deposits (MTDs) recognised both in outcrop studies and from offshore margins where they may extend for 100’s km. While seismic sections may reveal the large-scale geometry of such features, they fail to capture some of the structural and stratigraphic detail necessary for a fuller understanding of the processes involved. Using the late Pleistocene Lisan Formation sediments exposed around the Dead Sea Basin as our case study, we show that interplay between bed-parallel translational slides and associated normal faults may result in stratigraphic repetition through a process we term ‘slide stacking’. This mechanism, where retrogressive slope failure results in slides cutting across earlier normal faults, produces repeated sequences with older over younger stratigraphic relationships more usually attributed to compressional (thrust) deformation. Slide stacking results in a ∼25% attenuation of the upper sequence above the basal shear surface (BSS), which is itself associated with liquefaction and fluidised sediment. The displaced stratigraphy above the BSS is also marked by sedimentary rafts that are broken into blocks by normal faults and become increasingly separated from one another during downslope translation. The hangingwalls of synthetic listric faults form roll-overs that are progressively tightened towards the underlying BSS to create overturned anticlines that apparently verge upslope. The paradoxical situation therefore arises of contractional geometries, such as older over younger stratigraphic repetition across slides, and upslope-verging recumbent anticlines with locally overturned limbs being created during downslope-directed gravity-driven extension. The downslope margin of the slide stack displays earlier normal faults that created scarps where much of the sedimentary buttress, that would otherwise support the toe of the slide, was removed. Consequently, this leads to predominantly superficial and unrestrained downslope slipping, resulting in very localised contractional geometries that do not balance the overall extension, as in classical gravity-failure models. Localised deformation of the sedimentary sequence that unconformably overlies the slide stack indicates that downslope translation continued after the initial rapid slope failure, suggesting that the entire MTD remained inherently unstable. Slide stacking operates at km scales with stratigraphic repetition governed by the throw of earlier normal faults and the amount of downslope translation.
We investigate the intra- and inter-crystalline deformation processes involved in sheath fold development combining complementary fabric analysis techniques and 3D modelling by neutron tomography. The investigated sheath fold is a multi-layered sub-metre scale single-eye structure, developed in metapsammites from the Ben Hope Nappe, overlying the Moine Thrust Zone of NW Scotland. Crystallographic Preferred Orientations (CPOs) of quartz and biotite were acquired through a Neutron Diffractometer and an SEM-EBSD system to compare the full-fabric of the main phases and the active slip systems for an “in situ” structural control. Combined with orientation maps and grain size maps, results show that, despite the different structural positions of the investigated microdomains (upper vs lower fold limbs, inner vs outer sheath closures, distance from hinge of the sheath fold), quartz and biotite deformed uniformly, suggesting a constant differential stress and orientation of the kinematic vorticity axis. Previously recognized detachment horizons within the sampled sheath fold do not affect the fabric patterns recorded by quartz and biotite. This may be interpreted in two different ways: i) detachments formed during earlier active folding and prior to passive amplification of folds associated with more uniform flow to create the sheath fold geometries; ii) the quartz c-axis patterns are coeval with a late deformation phase (loading of the orogenic wedge) that pervasively obliterated the previous fabric and therefore did not preserve the active folding component. Several pieces of evidence reported here, such as top-to-SE normal-shear sense which is opposite to the regional kinematics, are more supportive of the second hypothesis. The analysis of mineral textures provides an improved dataset for the whole sheath fold and increases our understanding of recrystallization mechanisms active in shear zones.
Extracting tectonic signals from sediments in tectonically active areas is important for revealing the history of regional tectonic activity. However, in previous studies, tectonic and climatic signals have often been confused. In this study, we discuss the tectonic signals recorded in Quaternary sediments on the eastern Tibetan Plateau, combined with the geological, geomorphic, regional climate and geographical settings, and summarize six aspects of the sedimentary characteristics of tectonically generated gravels related to seismic landslides, providing an effective reference for other tectonically active areas. In addition, earthquakes commonly cause intermittent changes in the availability of fine particles in provenance areas, which is the rationale for revealing seismic events through a high-resolution sedimentary sequence from which hydrological fluctuations can not be easily identified. The tectonic control of Quaternary sedimentation on the eastern Tibetan Plateau has improved the previous crude understanding of water flow genesis and is of considerable significance for extending research on tectonic activity and assessing seismic hazards.
This study focused on collecting structural data orientations of a crustal-scale shear zone (Palmi Shear Zone, PSZ, southern Calabria, Italy) by integrating various analytical and field-based techniques. The PSZ consists of deformed metamorphic rocks (migmatitic biotitic paragneiss, marbles, and skarns) showing multiple folding phases, and Hercynian tonalites and pegmatites (306-290 Ma), crosscut by Late Hercynian leucocratic dykes (ca. 290 Ma). Multi-sized clasts composed of different lithologies are preserved on clean outcrop surfaces, and are sheared into both sigma - and delta -type objects that collectively suggest opposing senses of shear. The study incorporates structural analysis of folds, field and aerial surveys (UAV), digital mapping, and microcomputed tomography. Various kinematic indicators were observed in the PSZ, indicating a mix of factors influencing the shear strain patterns (e.g. fold interference patterns, different rock types with high viscosity contrast). The findings suggest a clear consistency between structural data inferred from 3D VOM (Virtual Outcrop Model) and those collected directly in the field, confirming the occurrence of both sinistral and dextral shear in the PSZ, providing important insights into the tectonic evolution of the Calabrian-Peloritani Terrane.
Bruno Vendeville (1961-2022) was the foremost practitioner of analog modeling applied to the field of salt tectonics, with his work providing and promoting significant advances in our understanding of this field over more than three decades. Bruno and his collaborators contributed major works in: the mechanics of salt-related deformation; the key processes of extensional, contractional, loading-induced, and strike-slip salt tectonics; the drivers and patterns of gravity-driven, linked systems of salt-detached deformation; and the structural style and evolution of specific salt basins. In this Special Issue devoted to his legacy, we offer a series of papers that build on his foundational work and honor his critical role in advancing the theory and application of salt tectonics.
Tectono-stratigraphic analysis coupled with digital 3D surface modelling derived from high-resolution seismic profiles is performed along a narrow turbidite basin offshore E-Sicily in order to increase understanding on the processes that contributed to the shaping of the Western Ionian Basin. Seismic-reflector patterns of the identified Pliocene-Quaternary sequence point to syn-depositional deformation during the Pliocene associated with the simultaneous activity of regional faults and underlying ductile units. Long-wavelength sediment fanning results from the extensional activity of the Malta Escarpment faults. Conversely, internal reflector architecture and lateral terminations indicate localized subsidence associated with the growth of uprising structures in the easternmost part of the basin. Lateral shifting of basin depocenters is in line with withdrawal effects observed in basins floored by ductile units (salt or shale). 3D modelling of time-reference surfaces highlights sub-circular depressions associated with nearby structural culminations. This pattern is similar to salt-withdrawal minibasins commonly reported in evaporite-floored basins. Accordingly, salt migration/flow triggered by sediment loading, locally enhanced by fault activity, is proposed as the process controlling basin evolution during the Pliocene in the Western Ionian Domain. Nevertheless, the possibility of shale/mud tectonics as the ductile source of deformation cannot be discounted.
Despite the recognition that bed-parallel slip (BPS) must operate during gravity-driven deformation of basinal sediments, there is a general paucity of detailed outcrop-based observations to characterise and detect such a process. We therefore present detailed timing relationships between BPS and steeper dip-slip faults that were both created during seismically-triggered downslope-directed movement of sediments. Using the late Pleistocene Lisan Formation that was deposited around the Dead Sea Basin as our case study, we show that 'sub-seismic' decametric scale BPS planes may pre-date, post-date, or operate coevally with steeper faults generated as sediments slip downslope towards the depocentre. Older BPS can be recognised by sediment injections and minor folds and fractures, whereas younger BPS displaces marker faults downslope towards the basin. BPS operating coevally with steeper faults results in complex overprinting and development of fault-bound lenses. BPS that forms along single surfaces in the footwall of normal faults becomes separated into two distinct planes in the downthrown hangingwall block, indicating broadly coeval development. Adjacent BPS planes that operate synchronously result in synthetic and antithetic faults that 'hard-link' and transfer displacement between BPS planes. Attenuated bedding between segments of BPS that overlap and terminate next to one another suggests that 'soft-linkage' also forms between coeval BPS planes. Displacement-length relationships of measured BPS planes plot in the same range as recorded for normal faults, although BPS with larger displacements have relatively 'short' lengths, suggesting that complete BPS planes are missing due to limitations of outcrop size. Although the lack of displaced bedding across BPS makes it largely invisible on seismic sections across large-scale gravity-driven systems, it does potentially contribute towards the apparent inbalance between net extension and contraction observed in many sections across mass transport deposits. In addition, the realisation that BPS interacts with dip-slip faults to create repeated and missing sections that are particularly focussed along earlier deformed horizons and turbidites, has implications for palaeoseismic studies that assume broadly continuous stratigraphy.
Tectono-stratigraphic interpretation and sequential restoration modelling was performed over two high-resolution seismic profiles crossing the Western Ionian Basin of southern Italy. This analysis was undertaken in order to provide greater insights and a more reliable assessment of the deformation rate affecting the area. Offshore seismic profiling illuminates the sub-seafloor setting where a belt of active normal faults slice across the foot of the Malta Escarpment, a regional-scale structural boundary inherited from the Permo-Triassic palaeotectonic setting. A sequential restoration workflow was established to back-deform the entire investigated sector with the primary aim of analysing the deformation history of the three major normal faults affecting the area. Restoration of the tectono-stratigraphic model reveals how deformation rates evolved through time. In the early stage, the studied area experienced a significant deformation with the horizontal component prevailing over the vertical element. In this context, the three major faults contribute to only one third of the total deformation. The overall throw and extension then notably reduced through time towards the present day and, since the middle Pliocene, ongoing crustal deformation is accommodated almost entirely by the three major normal faults. Unloading and decompaction indicate that when compared to the unrestored seismic sections, a revision and a reduction of roughly one third of the vertical displacement of the faults offset is required. This analysis ultimately allows us to better understand the seismic potential of the region.
Soft-sediment deformation structures associated with slumps and mass transport deposits (MTDs) are generally considered to form at the surface when unlithified sediment moves downslope under the influence of gravity. Where stratigraphic sequences contain several deformed horizons, the question arises as to whether repeated slope failure at the sediment surface has systematically built-up multiple MTDs in the stratigraphic record in a 'sequential failure model'. Alternatively, a single failure event may concurrently create surficial and sub-surface deformed 'intrastratal' horizons at different stratigraphic levels in a 'synchronous failure model'. The implications of these differing models are important as sub-surface deformation can be significantly younger than the depositional age of beds it affects thereby weakening age-depth correlations used to estimate the timing of palaeo-earthquakes. In order to investigate the potential for sub-surface deformation, we examine the late Pleistocene Lisan Formation exposed around the Dead Sea Basin that contains numerous MTDs and gravity-driven fold and thrust systems. Surficial deformation is recognised by identifying irregular erosive surfaces above MTDs that are overlain by sedimentary caps deposited out of suspension following the failure event. Such surficial deformation is also characterised by thickened sedimentary successions that create 'growth' sequences. Conversely, sub-surface intrastratal deformation is typified by detachment-bound folds and thrusts that are marked by repetitions of stratigraphy across the upper detachment surface, fluidised sediment that intrudes upwards into the overlying sequence, together with abrupt truncations of older faults developed in overburden above the detachment. MTDs created at the surface form relatively competent horizons when subsequently buried as they are internally disrupted and lack 'layer-cake' geometries, while repeated seismicity can lead to dewatering and compaction resulting in 'seismic strengthening'. Later sub-surface deformation may therefore be focussed adjacent to earlier MTDs that influence the mechanical stratigraphy, leading to secondary failures and complications when attempting to 'balance' extension and contraction that may be of different ages. Sub-surface deformation is localised along discrete detachments that carry the overlying sequence downslope as relatively intact slides, affecting what appear to be 'undeformed' beds between individual MTDs. As sub-surface deformation does not directly correlate with sedimentary caps, the rates of movement on deeper detachments remain unconstrained and may be significantly slower than surficial deformation resulting in downslope creep of the sediment pile.
Although sedimentary dykes have been widely reported across a range of settings, sedimentary sills have received somewhat less attention, perhaps due to the potential difficulties in identifying largely conformable intrusions within bedded sequences. Most outcrop descriptions of clastic intrusions are based on deep-water marine sequences, with few descriptions of sills in lacustrine settings. The recognition of sills in such settings is, however, important because lacustrine sequences are increasingly used as a record of palaeoseismic activity. The misidentification of sills that contain fragments and clasts of host stratigraphy with seismically-generated turbidites and debris flows, may lead to incorrect interpretations of palaeoseismicity. We use the Late Pleistocene Lisan Formation of the Dead Sea Basin as a case study, where laminated lake sediments preserve intricate relationships with sills. This permits us to not only establish a range of criteria used in the identification of sedimentary sills, but also examine relationships with adjacent seismically-triggered slumps and slides. Key criteria we use to recognise sills include marked changes in their thickness together with bifurcation and bridging geometries. Sills may be internally layered, contain lenses of breccia, together with aligned and folded clasts that may be truncated across upper sill contacts. Critical evidence for the interpretation of sills is also preserved along sharp but irregular upper contacts that erode and truncate bedding in the overlying host sequence. Minor apophyses and 'wedges' intrude both upwards and downwards from sills, while isoclinal recumbent 'peel-back' folds are created in host sediments by shear generated along the lower contacts of sills. We have undertaken anisotropy of magnetic susceptibility (AMS) analysis and find an oblate fabric that suggests flow and intrusion of sills along the strike of the slope, that may also help with their identification in bedded sequences. Sills form along detachments to both extensional and contractional deformation associated with seismically-generated slumps and mass transport deposits, together with sub-surface fold and thrust systems. High fluid pressures associated with injection of sedimentary sills may facilitate near-surface failure and downslope movement of the sedimentary pile.
Thrust collision zones with low slip rates along the plate boundary are significant areas of stress accumulation and prone to develop more destructive earthquakes with longer recurrence intervals. Such regions are often classified as low seismic risk if they lack continuous records of large earthquakes, such as the eastern Tibetan Plateau before the 2008 M w 7.9 Wenchuan earthquake. Here, we provide a continuous seismic record in the Longmen Shan thrust fault zone spanning 13,000 years based on detailed investigation of the soft-sediment deformation structures and seismites in the Lixian lacustrine sequence. The recurrence time of large earthquakes ( M ≥ 8.1) is 1,200 years, which is significantly shorter than the previous estimate of 2,000–6,000 years. The Maoxian-Wenchuan fault is the main fault that triggered the deformation in the Lixian lacustrine sediments. In addition, earthquake recurrence in the warm period is more frequent than that in the cold period, which should arouse our attention for the seismic study of tectonically active regions.
Palaeogene environmental evolution in East Asia remains ambiguous. Here we present integrative work including magnetostratigraphy, grain‐size, geochemistry, and clay mineralalogy from a 1609 m‐thick fluviolacustrine sequence in eastern China. The results reveal two periods of tectonic control alternating with three periods of climatic control on the sedimentary evolution. Tectonic activity in the study area, as revealed by particle coarsening and reduced weathering, occurred during 65.6–59 Ma and strengthened in Asia during 55–54 Ma in response to the India‐Eurasia collision. Weathering gradually enhanced in East Asia during 59–55 Ma, probably caused by global warming. Continuous global warming during 54–50.5 Ma is responsible for enhanced aridification in East Asia. From 50.5 to 37.6 Ma, global cooling weakened evapotranspiration and increased westerlies‐derived moisture. Both aspects increased effective moisture and chemical weathering in East Asia. These results shed light on how alternating tectonism and climate change impacted environmental evolution in Asia during the Palaeogene.
Sharp changes in lithology and increases in grain size and sedimentation rate of sedimentary sequences from tectonically active basins are often used to indicate regional neotectonic activity. However, these conventional methods have been challenged by others who argue that the sedimentary evidence used to infer tectonism could be climatically induced. Therefore, some forms of independent evidence or sedimentary criteria are required to discriminate between these two alternatives. Seismites, sedimentary units preserved in subaqueous stratigraphic sequences that are caused by seismic shaking, are reliable indicators of regional tectonic activity. Subaqueous paleoseismology, can extend the record of strong earthquakes and augment the understanding of fault zone tectonic activity by studying seismites preserved in subaqueous sedimentary sequences. Here, we use the Dead Sea Basin (Middle East) and the Qaidam Basin (NE Tibet) as examples to further understand regional neotectonic activity from the perspectives of subaqueous paleoseismology. The Dead Sea Basin is the deepest and largest continental tectonic structure in the world. In situ folded layers and intraclast breccia layer in the ICDP Core 5017-1 that recovered from the Dead Sea depocenter are identified as earthquake indicators, based on their resemblance to the lake outcrop observations of seismites that are known to be earthquake-induced. Based on the Kelvin-Helmholtz instability, we model the ground acceleration needed to produce each seismite by using the physical properties of the Dead Sea deposits. We invert acceleration for earthquake magnitude by considering regional earthquake ground motion attenuation, fault geometry, and other constraints. Based on the magnitude constraints, we develop a 220 kyr-long record of Mw ≥7 earthquakes. The record shows a clustered earthquake recurrence pattern and a group-fault temporal clustering model, and reveals an unexpectedly high seismicity rate on a slow-slipping (~5 mm/yr) plate boundary. We also propose a new approach to establish the seismic origin of prehistoric turbidites that involves analyzing in situ deformation that underlies each turbidite. Moreover, our sedimentological data validate a long-lasting hypothesis that soft-sediment deformation in the Dead Sea formed at the sediment-water interface. The Qaidam Basin is the largest topographic depression on the Tibetan Plateau that was formed by the ongoing India-Asia collision. The northeastward growth of Tibet formed a series of sub-parallel NW-SE-trending folds over a distance of ~300 km in the western Qaidam Basin. A long core was drilled in the basin on the crest of one such fold, the Jianshan Anticline. Sedimentological analysis reveals micro-faults, soft-sediment deformation, slumps, and detachment surfaces preserved in the core, which we interpret as paleoearthquake indicators. The core records five seismite clusters during 3.6-2.7 Ma. This suggests that the rate of tectonic strain accommodated by the folds/thrusts in the region varies in time and thus reveals episodic local deformation. During the clusters, regional deformation is concentrated more in the fold-and-thrust system than along regional major strike-slip faults. This kind of research provides a fresh perspective for understanding regional tectonism by linking paleoseismic events and recurrence patterns with regional deformation, and can expand the ability of paleoseismology to understand the history of regional tectonics.
We exploit the potential of magnetic fabrics acting as strain markers in folded layers, by analysing an exceptionally well-exposed, recent (<1 kyr) slump horizon in unlithified lake deposits within the Dead Sea basin. The similar to 3-m-long folded soft-sediment layer, together with an underlying basal detachment, and an 'undeformed' reference layer are extensively sampled (n = 97) for an anisotropy of magnetic susceptibility (AMS) analysis. This analysis reveals deformation fabrics within the folded layer which are significantly different from fabrics detected in the 'undeformed' layer. The maximum magnetic susceptibility axes (K-1) show a hinge-parallel orientation, and the minimum magnetic susceptibility axes (K-3) show a trail of orientations directed eastward parallel to the direction of downslope slumping toward the depocenter of the basin. In terms of shape of the AMS, samples from the 'undeformed' layer are oblate, while the majority of samples from the fold backlimb are oblate to neutral, and those from the forelimb and hinge zones are more prolate. We postulate that the deformation shown by the AMS analysis approximates well to sections through the strain ellipsoid in the folded layer, suggesting that magnetic fabrics serve as strain markers that are invisible to the naked eye. The deformation fabrics are created by particles moving relative to one another and reorganising during hydroplastic deformation. Particles physically rotate in the hinge zone, resulting in shortening of the intermediate axes and creation of more prolate shapes. The combination of two types of fabrics (deposition and deformation) in the hinge zones increases the intensity of the lineation due to the intersection of the primary and secondary fabrics (foliations). Based on the dense sampling scheme, we produce GIS-based interpolation maps that show the spatial distribution of the AMS parameters in the folded layer. These maps are compared to data from classical strain analyses, providing a benchmark for combining traditional structural methods and AMS analyses in studying folding and soft-sediment deformation.
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 synchronous deposition over large areas of a basin. Correlating historic earthquakes could potentially constrain the seismic intensities necessary for triggering turbidites, however this method is not applicable to prehistoric events. In addition, the synchronous deposition of turbidites cannot be verified for a single core record. Here, we propose a new approach to establish the seismic origin of prehistoric turbidites that involves analyzing in situ deformation that underlies each turbidite, as recorded in a 457 m-long core from the Dead Sea depocenter. These in situ deformations have been previously verified as seismites and could thus authenticate the trigger for each overlying turbidite. We also constrain the seismic intensities that triggered prehistoric turbidites by analyzing the degree of in situ deformation underlying each turbidite. Moreover, our high-resolution chemical and sedimentological data validate a long-lasting hypothesis that soft-sediment deformation in the Dead Sea formed at the sediment-water interface. 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 act as a model for other similar tectonic settings, by improving the completeness of a paleoseismic archive.
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.