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Colour three-dimensional regional elevation image of the northern Gulf of Eilat/Aqaba. The combined land – sea 20-m DTM was produced by merging the new multibeam data of the present study with lower-resolution Hydrosweep data ( arrow A ) from outside the
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A high-resolution marine geophysical study was conducted during October-November 2006 in the northern Gulf of Aqaba/Eilat,
providing the first multibeam imaging of the seafloor across the entire gulf head spanning both Israeli and Jordanian territorial
waters. Analyses of the seafloor morphology show that the gulf head can be subdivided into the Ei...
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... continuous land-sea, 20-m digital terrain model (DTM) grid was produced (Fig. 2) by merging the new multibeam data with lower-resolution Hydrosweep data collected outside the present survey area during the R/V Meteor cruise M44/3 in 1999 ( Ehrhardt et al. 2005), and with sounding from existing bathymetric maps (e.g. Hall and Ben-Avraham 1978). On land we used the 25-m DTM grid of Israel and the 90-m SRTM-3 grid of ...
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... by faults-the Evrona Fault zone to the west and the Ayla Fault zone to the east (Fig. 8). The Eilat Canyon appears to follow the Evrona Fault. Lineaments and offset features across the seafloor indicate that the Evrona Fault zone extends across the deep basinal floor. These lineaments are best seen on the three-dimensional perspective image in Fig. ...
Citations
... This mechanism etches wave-cut platforms and marine notches close to sea level and produces Communicated by Gabriele Uenzelmann-Neben. can image fine-scale and laterally extensive morphological features on the seafloor including reef terraces (i.e., Abbey et al., 2011;Beaman et al. 2008;Conway et al. 2005;Gomes et al. 2020;Kan et al. 2015;Khanna et al. 2017;Kim et al. 2013;Lebrec et al. 2022;de Silveira et al. 2020;Storlazzi et al. 2003;Tibor et al. 2010;Varzi et al. 2023;Vieira et al. 2023;Zecchin et al., 2015). Past studies in Hawaii (Grigg et al. 2002), Maldives (Fürstenau et al. 2010;Rovere et al. 2018), Australia (Abbey et al. 2011;Beaman et al. 2008;Lebrec et al. 2022), Gulf of Mexico (Khanna et al. 2017), Mediterranean Sea (Zecchin et al. 2015), Ryukyus, Japan (Inoue and Arai 2020), Rio Grande do Norte, Brazil (Gomes et al. 2020), and Abrolhos Shelf, Brazil (Vieira et al. 2023), have shown that the morphology of submerged reef terraces can provide regional interpretation of the origins and development of reefs even in the absence of age-dated materials. ...
The morphology of coral reefs provides an effective benchmark of past sea levels because of their limited vertical range of formation and good geologic preservation. In this study, we analyze the seafloor morphology around two atolls in the Philippines: Tubbataha Reef, in Palawan, and Apo Reef, in Occidental Mindoro. High-resolution multibeam bathymetry to a depth of 200 m reveals seafloor features including reef ridges and staircase-like terraces and scarps. Depth profiles across the reefs show terraces formed within six and seven depth ranges in Tubbataha Reef and in Apo Reef, respectively. These were further observed through a remotely operated vehicle. The terraces and scarps are interpreted as backstepping reefs that were drowned during an overall rise in sea level from the Last Glacial Maximum (LGM). Terraces are used as indicators of paleo sea level and the separation between terraces as the magnitude of sea-level rises coeval with meltwater pulse events during the last deglaciation. The pattern for both Apo and Tubbataha reefs indicates subsidence, consistent with the absence of Holocene emergent features and their atoll morphologies. Subsidence of up to 17 m since the LGM in Apo Reef is mainly attributed to the downbowing of the crust toward Manila Trench. In Tubbataha Reef, subsidence of up to 14 m is attributed to the continuous cooling of the volcanic crust underlying the atoll. These can be used to fill gaps in the tectonic history of the study sites from the last deglaciation.
... It separates the Arabian plate and Sinai microplate by trans-tensional deformation along the southernmost part of the ~1000-km-long left lateral strike-slip Dead Sea Fault (Ribot et al., 2021). The Gulf of Aqaba, which is approximately 180 km long and 25 km wide at its widest consists of four pull-apart basins or deeps (Ben-Avraham et al., 1979, 2008Tibor et al., 2010;Ribot et al., 2021); namely from north to south, Eilat (average depth: D avg : 900 m), Aragonese (D avg : 1750 m), Dakar (D avg : 1250 m) and Tiran (D avg : 1280 m) deeps. Trans-tensional deformation also formed the Hume deep (D avg : 1400 m), which is located just south of the Strait of Tiran. ...
Although ample historical and paleoseismological information is available on major past earthquakes along the onland part of the Dead Sea Fault, knowledge of the seismic behavior of its southernmost part in the Gulf of Aqaba has remained limited. To fill this gap and improve our understanding of the seismic potential of the submarine faults in the gulf, we analyzed 18 sediment cores ranging in length from 26.8 to 107.3 cm for sedimentary traces of past earthquakes. Radiographic images of the cores reveal numerous well-preserved turbidites intercalated within bioturbated background sediments. In addition, we used magnetic susceptibility, grain-size and µ-XRF data to detect instantaneous deposition in the sedimentary sequence and stratigraphically correlate the cores along the gulf. These results show coevality of some of the turbidites in cores from different basins of the gulf, which we used as the criterion to assign seismic origin for turbidites. In the top ∼1000 years of the sedimentary sequence, where the spatio-stratigraphical correlations are robust, seismo-turbidites caused by the known earthquakes of 1068, 1212, 1588, 1839, and CE 1995 were successfully detected. We found seismo-turbidites triggered by the 1995 earthquake only in the northern half of the gulf, confirming that this part of the fault system ruptured in 1995. On the other hand, the earthquakes in 1068 and CE 1588 triggered turbidites throughout the gulf, indicating that the entire fault system in the gulf was activated during these earthquakes. In addition, we detected seismo-turbidites of the 1212 and CE 1839 earthquakes only locally, suggesting these were smaller earthquakes. One core containing a sedimentary sequence back to ∼1800 BCE shows likely seismo-turbidites around CE 363, 250 BCE, 850 BCE and 1350 BCE. Together with the 1588 and 1068 earthquakes, these older possible seismo-turbidites may indicate a 400–700 (average = 560) year recurrence interval for large earthquakes in the gulf. Absence of significant turbidites in the southern gulf since CE 1588 therefore implies that this part of the fault system could be a candidate for a large earthquake in the near future.
... We choose to analyse in detail LBF shells as their assemblages in the gulf vary depending on water depth, making them an excellent indicator for the original life habitat. The gulf continental shelf is very narrow, and averages 585 m in width at the western subbasin (Tibor et al., 2010) where the cores were collected from, meaning the biogenic sediment sources are very restricted. Noticeably, only LBF are sensitive enough to define depth differences along the shelf (Reiss & Hottinger, 1984;Perelis-Grossowicz et al., 2008; fig. 1 in Ash-Mor et al., 2017). ...
The introduction of the comment by Reijmer certainly describes the major aspects that were addressed in our paper and we thank him for his critical reading of our work. In our response, we refer to both the paper published in Sedimentology (Ash‐Mor et al., 2022) and to Ash‐Mor et al. (2017), published in Marine Geology, because Reijmer's comments also refer to it.
... The thicker blue line follows the route of the artificially regulated Kinnet Canal that drains several ephemeral rivers to the GAE near the study area, onto the shallow shelf. Seafloor bathymetry is marked with both a color gradient and isobaths (adapted from Tibor et al., 2010). The blue dot labeled 'IUI' indicates the location where wave measurements were collected. ...
The evolution and preservation of flood deposits on continental shelves offshore river mouths is influenced by the dynamic relationship between punctuated discharge events and post-deposition processes. These short-term dynamic changes at the seafloor that ultimately shape the sedimentary record are difficult to monitor and not well understood. The aim of this study was to examine how punctuated deposition of flood sediments from a coastal river on the continental shelf, biological mixing and winnowing interplay in shaping grain size profiles and their transient evolution, and flood layers preservation in the sedimentary record. For this end an observations’-based model was devised for the northern shelf of the sheltered, hyper-arid Gulf of Aqaba-Eilat, where infrequent floods from ephemeral rivers occur ∼ yr⁻¹ and there is low physical perturbation by currents and waves in between; conditions that facilitate the examination of grain size profiles' evolution in time. The model shows that in between floods mixing and winnowing shape grain size profiles in the seafloor causing the sediment to coarsen from the top down and shape a subsurface peak of the fine flood-sediments. Over longer time periods, without additional floods, mixing and winnowing gradually erase the peak of fines, coarsening the entire mixed layer (as also seen in sediment cores) thus nulling the flood layers' chances of preservation. This important role of winnowing near the sediment surface is missing in previous studies. Concurrently, our modelling suggests that long-term positive sedimentation, usually estimated on the years' time-scale, is comprised of a series of short-term, steep sediment deposition events brought by the punctuated floods (lasting hours to days) and followed by a gradual (months to years' time-scale) winnowing of finer sediments (erosion). These high-resolution dynamics that were captured by the model and included short-term flood depositions and their reoccurrence, could not be deduced from the long-term sedimentary records.
... Seismicity is common. Earthquakes in the area frequently exceed M w = 5.0, including the 1995 M w = 7.3 Nuweiba earthquake which resulted from a partial rupture of the Aragonese fault [37][38][39][40][41][42] . ...
... This second interpretation bears consideration given that the calibrated 14 C age of the youngest coarse interval in the core, 50 yr. BP closely corresponds to the 1995 Nuweiba earthquake (M w = 7.1) [37][38][39]41 . This earthquake occurred along the Aragonese fault within the Aragonese Deep, the small pull-apart basin in which the NEOM Brine Pools locate, generating a modest tsunami 42 . ...
Deep-sea brine pools represent hypersaline environments famed for their extremophile microbes. With anoxia entirely excluding bioturbating megafauna, brine pools are also conducive to the pristine preservation of sedimentary sequences. Here we use bathymetric and geophysical observations to locate a complex of brine pools in the Gulf of Aqaba consisting of one 10,000 m 2 pool and three minor pools of less than 10 m 2. We further conduct sediment coring and direct sampling of the brine to confirm the sedimentary and environmental characteristics of these pools. We find that the main pool preserves a stratigraphy which spans at least 1200 years and contains a combination of turbidites, likely resulting from flashfloods and local seismicity, and tsunamigenic terrestrial sediment. The NEOM Brine Pools, as we name them, extend the known geographical range of Red Sea brine pools, and represent a unique preservational environment for the sedimentary signals of regional climatic and tectonic events.
... Seismicity is common. Earthquakes in the area frequently exceed M w = 5.0, including the 1995 M w = 7.3 Nuweiba earthquake which resulted from a partial rupture of the Aragonese fault [37][38][39][40][41][42] . ...
... This second interpretation bears consideration given that the calibrated 14 C age of the youngest coarse interval in the core, 50 yr. BP closely corresponds to the 1995 Nuweiba earthquake (M w = 7.1) [37][38][39]41 . This earthquake occurred along the Aragonese fault within the Aragonese Deep, the small pull-apart basin in which the NEOM Brine Pools locate, generating a modest tsunami 42 . ...
We present the NEOM Brine Pools, the first complex of brine pools discovered in the Gulf of Aqaba. The discovery was made at 1,770 m water depth and consists of one large pool (10,000 m ² ) flanked by three minor ones (<10 m ² ). Situated immediately at the toe-of-slope, the largest of the NEOM brine pools episodically receives terrestrial outwash from the Saudi coastal plain. A transect of cores through this pool’s bed reveals a stratigraphy spanning the last 1,200 yrs. Major terrestrial inputs to the basin are recorded once per century, which we attribute to tsunami. Turbidite beds, meanwhile, deposit every 25 yrs. and likely record both flashfloods and the pervasive seismicity of the Aragonese Deep, the pull-apart basin in which the pools situate. Such signals are exquisitely preserved beneath the pools as bioturbating organisms cannot occupy the harsh hypersaline, anoxic brine. These observations extend the known geographical range of Red Sea brine pools, introduce a new sediment archive of event horizons, and document a new bathyal ecosystem in the Gulf of Aqaba; ultimately providing a range of significant data that will contribute to the reconstruction of more than one millennium of preserved turbidites, flashfloods, and tsunami sedimentary deposits.
... Much focus has been placed on the 1995 Nuweiba earthquake (Mw=7.1) that occurred along the DST fault system (Abdel-Fattah et al., 1997;Baer et al., 1999;Klinger et al., 1999;Tibor et al., 2010), generating a modest tsunami (Frucht et al., 2019). The 1969 Shadwan earthquake (Mw=6.8) ...
The Red Sea is a maritime rift. Tsunamigenic submarine landslides are common in these deep, steep-sided, and seismically active basins. Because the rift is narrow, tsunami formed on one margin dissipate little before impacting the opposite side. Red Sea slope failures are therefore especially hazardous. We examine the tsunamigenic potential of an incipient landslide in the Tiran Straits that started, but then stopped after a short distance. Radiometric and biotic analyses fix the age of this landslide to within the last 500 years. Tsunami modelling of the incipient slide predicts ∼10 m wave heights on the Egyptian coastline. Of present concern is that the slope will eventually slide to completion with even more hazardous results. Tsunami simulated for this future event are twice as large as that generated by the incipient slide, so the threat posed by a future slide is consequential. Sharm El Sheikh, an Egyptian resort town now lies in its path, as does ‘The Line’ – a vast Saudi infrastructure project. This study warns of credible tsunami risk in the rapidly urbanizing Tiran Straits.
... Slow subsidence was ruled out in favor of a shock that enabled a swift transition through the wave action zone, that for the energetic southern storms would reach 2 m. A more recent work by Tibor et al. (2010) suggests that the entire continental slope offshore the NRR has slid down-slope, leaving slump scars. The bathymetric map of Tibor et al. (2010) is reproduced in the Supplement (Supp. ...
... A more recent work by Tibor et al. (2010) suggests that the entire continental slope offshore the NRR has slid down-slope, leaving slump scars. The bathymetric map of Tibor et al. (2010) is reproduced in the Supplement (Supp. Fig. S3). ...
A new relative sea level (RSL) curve is presented for the Holocene Gulf of Aqaba, northern Red Sea. The curve is based on U–Th ages of corals retrieved from leveled fossil reefs comprising the Tur Yam Terrace at the shore of the city of Elat, Israel and the Aqaba reef terraces, Jordan, located respectively east and west of the northern tip of the gulf. Both terrace tops are submerged under high tide and subaerial at low tide. The fossil corals are in growth position between two beachrock units. The corals comprise 100% aragonite, show pristine textures with no secondary aragonite cements and yield initial ²³⁴U/²³⁸U activity ratios of 1.146 ± 0.004, similar to the values of live corals and modern Gulf of Aqaba (GoA) waters. Sixteen U–Th ages of corals from the Tur Yam Terrace span the time interval of 6.8 to 5.5 ka, and are ordered along the growth direction of the terrace. Detailed mapping of the terrace, the distribution of corals’ genera and the order of their ages on the terrace, suggest that the exposed terrace was the back reef/lagoon zone, a very close to shore environment of a fringing reef. Identification of this reef zone was based on a detailed ecological study that we conducted on the Nature Reserve Reef (NRR), a modern fringing reef located several hundred meters to the south. A morpho-tectonic analysis of the Elat shore indicates that the Tur Yam Terrace lies on top of the footwall of the active Elat Fault and has remained at its original level, with negligible vertical shift. Thus, it appears that during the time interval of formation of the Tur Yam corals, sea level at GoA reached a maximum stand that was 1–2 m above the modern elevation. A similar figure is shown by Mid-Holocene corals from the Aqaba fossil reefs and shore indicators from the Red Sea. The relative sea level (RSL) curve deduced from the Gulf of Aqaba corals and from the Red Sea indicators resembles those of precisely-dated stable reefs off west and east Australia and a few other well dated reefs in the Indo-Pacific. This similarity calls for coeval response of the Indo-Pacific oceans to ice melting during the early to mid- Holocene, and a similar pattern of decline to the present level during the late Holocene. Such a coeval rise of distant parts of the Indo-Pacific oceans is consistent with dominance of melt waters releases over the oceans with minor effects of all other “sea level drivers".
... Lionfish surveys conducted within the study site found that P. miles' mean density was 2.1 ± 1.8 (SD) individuals per 500 m 2 (Gavriel and Belmaker, 2020). The Gulf of Aqaba in general, and the study site in particular, are characterized by a narrow shelf with fringing reefs, followed by a steep slope that descends to depths of 60 m within 200 m from shore (Sade et al., 2008;Tibor et al., 2010). The selected study site was spread over 2.5 km and encompassed multiple sub-habitats such as hardbottom substrates, soft-bottom substrates, and continuous and fragmented fringing reefs. ...
The common lionfish, Pterois miles, a notoriously invasive species known for its harmful effect on native fish communities in the Atlantic Ocean, has recently begun spreading across the Mediterranean Sea. The wide niche breadth of the lionfish has been hypothesized to facilitate its invasion success. However, it is unclear to what extent this wide niche-breadth is associated with individual-level variation and repeatable behavior over time. Large individual-level behavioral variations may allow individuals to adapt quickly to local conditions, increasing the species’ chance of invasion success and complicating mitigation efforts. In this study, we used an acoustic telemetry system in P. miles’ native Red Sea environment to explore individual-level variation in depth preference and diel activity. A wide depth range may indicate an ability to tolerate a variety of biotic and abiotic conditions, and variability in diel activity may indicate an ability to exploit multiple diet sources. We found large individual-level variability in P. miles’ activity hours; although all tracked fish were active during both sunrise and sunset, certain individuals had prolonged activity hours to variable extents. Moreover, individuals often change their patterns over time, showing low repeatability. We also found that individuals had different depth preferences and commuted between shallow and deep waters over short periods of time. This study is one of the first to explore diel activity as an individual-level trait in wild fish. The variability found in depth and diel activity is likely one of the reasons P. miles has been so successful in invading the Mediterranean Sea. In addition, this variability may impact mitigation efforts within the Mediterranean Sea as nocturnal individuals from deeper waters might replenish diurnally culled shallow-water populations.
... Indeed, Ash-Mor et al. (2017) identified two types of turbidites consisting either of 20 to 30% or >70% sandy sediments, compared to the pelagic sediments that consist of <20% (see fig. 6 in Ash-Mor et al., 2017), considering the limited source area for shelf originated sediments as the western continental shelf width is ca 600 m on average (Tibor et al., 2010). The experiment results suggest that turbidites that comprise large volumes of coarse sediments and LBF shells represent mass flow processes initiated by high current velocities (see turbidites in core MG10P27 in Fig. 1B). ...
... The experimental flow velocities used in the present study examine the boundary conditions necessary for the initiation of sediment-transport processes at the deeper continental shelf and slope. At the western GEA, the gradient angles are 9°and 17°, respectively (Tibor et al., 2010;Fig. 1E). ...
Transport of continental shelf sediments to the deep ocean can be studied from displaced symbiont‐bearing larger benthic foraminifera found in turbidity current deposits. The larger benthic foraminifera habitat depth, physical characteristics and preservation serve as indicators for understanding sediment transport dynamics near the seabed and in the water column. Here, an experiment was designed to explore sediment transport in a closed flume system using simulated high current velocities. Shelf sediments from the Gulf of Eilat/Aqaba, dominated by Amphistegina papillosa and Operculina ammonoides, were subjected to 60 and 80 cm/sec current velocities while collected in a 10 cm vertical sediment trap. Larger benthic foraminifera abundance, shell physical properties and preservation were analyzed and compared with the original bulk sediments. The experiment results showed that at 80 cm/sec velocity, larger benthic foraminifera shells of all sizes and preservations are efficiently resuspended and transported in large quantities throughout the water column, as opposed to their transport as bedload by the lower velocity current. Larger benthic foraminifera shape also has a role in the transport distances and accumulation depths. Operculina ammonoides shells were found more portable, compared to Amphistegina papillosa, due to their flatter discoid shape. The results suggest that a threshold velocity of ca 80 cm/sec was needed to generate the thick coarse deposits found in the Gulf of Eilat/Aqaba slope sedimentary record, which were previously suggested to be triggered by large magnitude seismic events. Lower velocities probably winnowed minor amounts of larger benthic foraminifera shells (with little or no coarser sediments) that were deposited as thin sand layer may point to lower magnitude seismic triggers. In conclusion, larger benthic foraminifera shells are transported and deposited in accordance to their hydrodynamic properties, resulting in assemblage differentiation along the transport pathway. This study shows that the fossil biogenic composition in slope sediments include valuable information on current velocities, transport dynamics and possible triggers in the geological record.
