Active faults' geometry in the Gulf of Aqaba, southern Dead Sea fault, illuminated by multi beam bathymetric data

Initially described in the late 50&#8217;s, the Dead Sea Fault system connects at its southern end to the Red Sea extensive system, through a succession of left-stepping faults. In this region, the left-lateral differential displacement of the Arabian plate with respect to the Sinai micro-plate along the Dead Sea fault results in the formation of a depression corresponding to the Gulf Aqaba. We acquired new bathymetric data in the areas of the Gulf of Aqaba and Strait of Tiran during two marine campaigns (June 2018, September 2019) in order to investigate the location of the active faults, which structure and control the morphology of the area. The high-resolution datasets (10-m posting) allow us to present a new fault map of the gulf and to discuss the seismic potential of the main active faults.We also investigated the eastern margin of the Gulf of Aqaba and Tiran island to assess the vertical uplift rate. To do so, we computed high-resolution topographic data and we processed new series of U-Th analyses on corals from the uplifted marine terraces.Combining our results with previous studies, we determined the local and the regional uplift in the area of the Gulf of Aqaba and Strait of Tiran.Eventually, we discussed the tectonic evolution of the gulf since the last major change of the tectonic regime and we propose a revised tectonic evolution model of the area.&#160;

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Liquefaction susceptibility maps for the Aqaba–Elat region with projections of future hazards with sea-level rise

Quarterly Journal of Engineering Geology and Hydrogeology ◽

10.1144/qjegh2020-039 ◽

2020 ◽

pp. qjegh2020-039 ◽

Cited By ~ 1

Author(s):

Abdel-Rahman A. Abueladas ◽

Tina M. Niemi ◽

Abdallah Al-Zoubi ◽

Gideon Tibor ◽

Mor Kanari ◽

...

Keyword(s):

Sea Level ◽

Water Table ◽

Active Faults ◽

Gulf Of Aqaba ◽

Susceptibility Map ◽

Northern Coast ◽

Borehole Data ◽

Ground Acceleration ◽

Liquefaction Susceptibility ◽

Susceptibility Maps

The cities of Aqaba, Jordan and Elat, Israel are vulnerable to seismic damage because they are built over the active faults of the Dead Sea Transform that are the source of historically destructive earthquakes. A liquefaction susceptibility map was generated for the Aqaba–Elat region. Borehole data from 149 locations and the water table depth were used to calculate effective overburden stress in the Seed–Idriss simplified method. The liquefaction analysis was based on applying a cyclic loading scenario with horizontal peak ground acceleration of 0.3 g in a major earthquake. The liquefaction map, compiled using a GIS platform, shows high and moderate liquefaction susceptibility zones along the northern coast of the Gulf of Aqaba that extend 800 m inland from the shoreline. In Aqaba, several hotels, luxury apartment complexes, archaeological sites, ports and commercial districts are located within high and moderate liquefaction zones. In Elat, the seaport and the coastal hotel district are located within a high susceptibility zone. Most residential areas, schools and hospitals in both cities are located within zones not susceptible to liquefaction based on the methods of this study. The total area with the potential to be liquefied along the Gulf of Aqaba is c. 10 km2. Given predictions for global sea-level, we ran three liquefaction models utilizing projected water table rises of 0.5, 1 and 2 m. These models yielded an increase in the area of high liquefaction ranging from 26 to 49%. Given the high potential of future earthquakes, our liquefaction susceptibility maps should help inform city officials for hazard mitigation planning.

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Empirical Relationship for Assessing the Near-Field Horizontal Coseismic Displacement Using GPS Seismology Data

Geofísica Internacional ◽

10.22201/igeof.00167169p.2021.60.1.2025 ◽

2021 ◽

Vol 60 (1) ◽

pp. 31-50

Author(s):

Ryad Darawcheh ◽

Riad Al Ghazzi ◽

Mohamad Khir Abdul-wahed

Keyword(s):

Near Field ◽

Empirical Relationship ◽

Active Faults ◽

Historical Earthquakes ◽

Dead Sea ◽

Fault System ◽

Coseismic Displacement ◽

Data Set ◽

Earthquake Parameters ◽

Gps Station

In this research, a data set of horizontal GPS coseismic displacement in the near-field has been assembled around the world in order to investigate a potential relationship between the displacement and the earthquake parameters. Regression analyses have been applied to the data of 120 interplate earthquakes having the magnitude (Mw 4.8-9.2). An empirical relationship for prediction near-field horizontal GPS coseismic displacement as a function of moment magnitude and the distance between hypocenter and near field GPS station has been established using the multi regression analysis. The obtained relationship allows assessing the coseismic displacements associated with some large historical earthquakes occurred along the Dead Sea fault system. Such a fair relationship could be useful for assessing the coseismic displacement at any point around the active faults.

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Seismic structure beneath the Gulf of Aqaba and adjacent areas based on the tomographic inversion of regional earthquake data

Solid Earth ◽

10.5194/se-7-965-2016 ◽

2016 ◽

Vol 7 (3) ◽

pp. 965-978 ◽

Cited By ~ 7

Author(s):

Sami El Khrepy ◽

Ivan Koulakov ◽

Nassir Al-Arifi ◽

Alexey G. Petrunin

Keyword(s):

Travel Time ◽

Red Sea ◽

Lateral Displacement ◽

Dead Sea ◽

Gulf Of Aqaba ◽

Seismic Structure ◽

Time Data ◽

Tomographic Inversion ◽

Velocity Anomaly ◽

Surrounding Areas

Abstract. We present the first 3-D model of seismic P and S velocities in the crust and uppermost mantle beneath the Gulf of Aqaba and surrounding areas based on the results of passive travel time tomography. The tomographic inversion was performed based on travel time data from ∼ 9000 regional earthquakes provided by the Egyptian National Seismological Network (ENSN), and this was complemented with data from the International Seismological Centre (ISC). The resulting P and S velocity patterns were generally consistent with each other at all depths. Beneath the northern part of the Red Sea, we observed a strong high-velocity anomaly with abrupt limits that coincide with the coastal lines. This finding may indicate the oceanic nature of the crust in the Red Sea, and it does not support the concept of gradual stretching of the continental crust. According to our results, in the middle and lower crust, the seismic anomalies beneath the Gulf of Aqaba seem to delineate a sinistral shift (∼ 100 km) in the opposite flanks of the fault zone, which is consistent with other estimates of the left-lateral displacement in the southern part of the Dead Sea Transform fault. However, no displacement structures were visible in the uppermost lithospheric mantle.

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Seismic structure beneath the Gulf of Aqaba and adjacent areas based on the tomographic inversion of regional earthquake data

10.5194/se-2016-2 ◽

2016 ◽

Cited By ~ 2

Author(s):

Sami El Khrepy ◽

Ivan Koulakov ◽

Nassir Al-Arifi ◽

Alexey Petrunin

Keyword(s):

Travel Time ◽

Red Sea ◽

Lateral Displacement ◽

Relative Displacement ◽

Dead Sea ◽

Gulf Of Aqaba ◽

Seismic Structure ◽

Time Data ◽

Tomographic Inversion ◽

Seismic Anomalies

Abstract. The Gulf of Aqaba is an elongated basin (~180 x 20 km) with depths reaching 1850 m. It represents the southern segment of the Dead Sea Transform (DST), which is one of the largest transform fault zones in the world. The opening of Gulf of Aqaba is thought to have originated from the relative displacement of the African and Arabian Plates. According to historical and recent earthquake records, it is seismically active. In this study, we present the first 3D model of seismic P and S velocities beneath the Gulf of Aqaba area based on the results of passive travel time tomography. The tomographic inversion was performed based on travel time data from ~9000 regional earthquakes provided by the Egyptian National Seismological Network (ENSN) and the International Seismological Center (ISC). The inversion results are generally consistent for P- and S-velocity patterns at all depths. At all depth intervals in the Red Sea, we observed strong high-velocity anomalies with abrupt limits that coincide with the coastal lines. This finding suggests that the oceanic nature of the crust in the northern Red Sea does not support the concept of gradual stretching of the continental crust. According to our results, in the middle and lower crust, the seismic anomalies seem to delineate a sinistral shift (~100 km) in the opposite flanks of the fault zone that is consistent with other estimates of the left-lateral displacement in the southern part of the DST. However, no displacement structures are visible in the upper-most lithospheric mantle.

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Remote Earthquake Triggering along the Dead Sea Fault in Syria following the 1995 Gulf of Aqaba Earthquake (Ms = 7.3)

Seismological Research Letters ◽

10.1785/gssrl.71.1.47 ◽

2000 ◽

Vol 71 (1) ◽

pp. 47-52 ◽

Cited By ~ 20

Author(s):

R. Mohamad ◽

A. N. Darkal ◽

D. Seber ◽

E. Sandvol ◽

F. Gomez ◽

...

Keyword(s):

Dead Sea ◽

Gulf Of Aqaba ◽

Earthquake Triggering ◽

The Dead

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Seismic and Geodetic Crustal Moment-Rates Comparison: New Insights on the Seismic Hazard of Egypt

Applied Sciences ◽

10.3390/app11177836 ◽

2021 ◽

Vol 11 (17) ◽

pp. 7836

Author(s):

Rashad Sawires ◽

José A. Peláez ◽

Federica Sparacino ◽

Ali M. Radwan ◽

Mohamed Rashwan ◽

...

Keyword(s):

Active Regions ◽

Seismic Source ◽

Satellite System ◽

Dead Sea ◽

Fault System ◽

Gulf Of Aqaba ◽

Seismic Sources ◽

Earthquake Catalog ◽

Focal Mechanism Solutions ◽

Rate Ratios

A comparative analysis of geodetic versus seismic moment-rate estimations makes it possible to distinguish between seismic and aseismic deformation, define the style of deformation, and also to reveal potential seismic gaps. This analysis has been performed for Egypt where the present-day tectonics and seismicity result from the long-lasting interaction between the Nubian, Eurasian, and Arabian plates. The data used comprises all available geological and tectonic information, an updated Poissonian earthquake catalog (2200 B.C.–2020 A.D.) including historical and instrumental datasets, a focal-mechanism solutions catalog (1951–2019), and crustal geodetic strains from Global Navigation Satellite System (GNSS) data. The studied region was divided into ten (EG-01 to EG-10) crustal seismic sources based mainly on seismicity, focal mechanisms, and geodetic strain characteristics. The delimited seismic sources cover the Gulf of Aqaba–Dead Sea Transform Fault system, the Gulf of Suez–Red Sea Rift, besides some potential seismic active regions along the Nile River and its delta. For each seismic source, the estimation of seismic and geodetic moment-rates has been performed. Although the obtained results cannot be considered to be definitive, among the delimited sources, four of them (EG-05, EG-06, EG-08, and EG-10) are characterized by low seismic-geodetic moment-rate ratios (<20%), reflecting a prevailing aseismic behavior. Intermediate moment-rate ratios (from 20% to 60%) have been obtained in four additional zones (EG-01, EG-04, EG-07, and EG-09), evidencing how the seismicity accounts for a minor to a moderate fraction of the total deformational budget. In the other two sources (EG-02 and EG-03), high seismic-geodetic moment-rates ratios (>60%) have been observed, reflecting a fully seismic deformation.

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Interseismic deformation in the gulf of aqaba from GPS measurements

Geophysical Journal International ◽

10.1093/gji/ggab353 ◽

2021 ◽

Author(s):

Nicolás Castro-Perdomo ◽

Renier Viltres ◽

Frédéric Masson ◽

Yann Klinger ◽

Shaozhuo Liu ◽

...

Keyword(s):

Gulf Coast ◽

Accumulation Rate ◽

Slip Rate ◽

Dead Sea ◽

Northern Region ◽

Fault System ◽

Gulf Of Aqaba ◽

Dead Sea Transform ◽

Red Sea Rift ◽

The Dead

Summary Although the Dead Sea Transform fault system has been extensively studied in the past, little has been known about the present-day kinematics of its southernmost portion that is offshore in the Gulf of Aqaba. Here we present a new GPS velocity field based on three surveys conducted between 2015 and 2019 at 30 campaign sites, complemented by 11 permanent stations operating near the gulf coast. Interseismic models of strain accumulation indicate a slip rate of $4.9^{+0.9}_{-0.6}~mm/yr$ and a locking depth of $6.8^{+3.5}_{-3.1}~km$ in the gulf’s northern region. Our results further indicate an apparent reduction of the locking depth from the inland portion of the Dead Sea Transform towards its southern junction with the Red Sea rift. Our modelling results reveal a small systematic left-lateral residual motion that we postulate is caused by, at least in part, late postseismic transient motion from the 1995 MW7.2 Nuweiba earthquake. Estimates of the moment accumulation rate on the main faults in the gulf, other than the one that ruptured in 1995, suggest that they might be near the end of their current interseismic period, implying elevated seismic hazard in the gulf area.

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Active faulting in the Gulf of Aqaba: New knowledge from the MW 7.3 earthquake of 22 November 1995

Bulletin of the Seismological Society of America ◽

10.1785/bssa0890041025 ◽

1999 ◽

Vol 89 (4) ◽

pp. 1025-1036 ◽

Cited By ~ 7

Author(s):

Yann Klinger ◽

Luis Rivera ◽

Henri Haessler ◽

Jean-Christophe Maurin

Keyword(s):

Body Wave ◽

Background Level ◽

Dead Sea ◽

Strike Slip ◽

Historical Seismicity ◽

Global Network ◽

Arabian Plate ◽

Gulf Of Aqaba ◽

African Plate ◽

Slip Mechanism

Abstract On 22 November 1995 the largest earthquake instrumentally recorded in the area, with magnitude MW 7.3, occurred in the Gulf of Aqaba. The main rupture corresponding to the strike-slip mechanism is located within the gulf of Aqaba, which forms the marine extension of the Levantine fault, also known as the Dead Sea fault. The Levantine fault accommodates the strike-slip movement between the African plate and the Arabian plate. The Gulf of Aqaba itself is usually described as the succession of three deep pull-apart basins, elongated in the N-S direction. Concerning historical seismicity, only two large events have been reported for the last 2000 years, but they are still poorly constrained. The seismicity recorded since installation of regional networks in the early 1980s had been characterized by a low background level punctuated by brief swarmlike activity a few months in duration. Three swarms have already been documented in the Gulf of Aqaba in 1983, 1990, and 1993, with magnitudes reaching at most 6.1 (MW). We suggest that the geometry of the rupture for the 1995 event is related to the spatial distribution of these previous swarms. Body-wave modeling of broadband seismograms from the global network, along with the analysis of the aftershock distribution, allow us to propose a well-constrained model for the rupture process. Northward propagation of the rupture has been found. We have demonstrated that three successive subevents are necessary to obtain a good fit between observed and synthetic wave forms. The total seismic moment released was 7.42 × 1019 N-m. The location of the subsevents shows that the three stages of the rupture involve three different segments within the gulf. Substantial surface breakage showing only normal motion (up to 20 cm) affecting beachrock was observed along the Egyptian coast. We show that these ruptures are only a secondary feature and are in no case primary ruptures. The stress tensor derived from striations collected in quaternary sediments shows radial extension. This result supports landsliding of the beach terraces under the action of the earthquake shaking.

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