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Location of trenches and core sites at (a) Kefr Saber, (b) El Alamein (see Fig. 1), and (c) dune ridge and a lagoon south of the Mediterranean Sea as a selected site for coring and trenching at the El Alamein site.
Source publication
We study the sedimentary record
of past tsunamis along the coastal area west of Alexandria (NW Egypt) taking
into account the occurrence of major historical earthquakes in the eastern
Mediterranean. The two selected sites at Kefr Saber ( ∼ 32 km west of
Marsa-Matrouh city) and ∼ 10 km northwest of El Alamein village are
coastal lagoons protected by...
Contexts in source publication
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... that are mostly composed of oolitic grains ( Frihy et al., 2010). The beach-dune ridge is developed along the receding Quaternary shorelines and embayment of the Mediterranean Sea (Hassouba, 1995). Coastal dune-ridges protect inner la- goons from the sea and constitute outstanding landform fea- tures at several locations parallel to the shoreline (Fig. 2). When the sand dunes are removed they leave rocky head- land outcrops ( Abbas et al., 2008). The 2-20 m-high coastal beach-dune ridges are mainly composed of oolitic and bio- genic calcareous sand and separate the coastal lagoons and sabkhas (salt water) from the sea. The lagoons with flat de- pressions separated from the sea by the ...
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... the lagoon. Two sites (∼ 200 km part) within seasonally dry lagoons have met the selection criteria for paleotsunami investigation (Figs. 1 and 2): (1) Kefr Saber located ∼ 32 km west of Marsa-Matrouh city; and (2) the El Alamein site, ∼ 10 km northwest of El Alamein city and ∼ 150 km west of Alexandria. Five trenches were dug at Kefr Saber ( Fig. 2a), and 12 cores taken at the El Alamein site (Fig. ...
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... dry lagoons have met the selection criteria for paleotsunami investigation (Figs. 1 and 2): (1) Kefr Saber located ∼ 32 km west of Marsa-Matrouh city; and (2) the El Alamein site, ∼ 10 km northwest of El Alamein city and ∼ 150 km west of Alexandria. Five trenches were dug at Kefr Saber ( Fig. 2a), and 12 cores taken at the El Alamein site (Fig. ...
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... 12 cores extend between 1 and 2.6 m depth. Except, for cores 1 and 9, which are shown in Fig. 5a and b, the detailed stratigraphic logs and related measurements are presented in Fig. S2. In a previous reconnaissance field investigation, a coarse and fine white sand layer was identified at ∼ 30 cm below the surface in a test pit. Two charcoal samples El Al sa1 and El Al sa2 collected at a 25 and 56 cm depth gave ages of AD 1680-1908and AD 1661-1931, respectively. The de- scription of cores is as ...
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... 1. This core is located ∼ 166 m from the shore- line (Fig. 2b) ∼ 2.14 m and the stratigraphic section includes four high en- ergy sedimentary layers recognized as follows (Fig. 5a, sec- tion 1 of core 1 and its continuation at depth in Fig. ...
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... 1. This core is located ∼ 166 m from the shore- line (Fig. 2b) ∼ 2.14 m and the stratigraphic section includes four high en- ergy sedimentary layers recognized as follows (Fig. 5a, sec- tion 1 of core 1 and its continuation at depth in Fig. ...
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... yellow sand with poor sort- ing of sediments, and a high peak in magnetic susceptibility. The chemical analysis shows the presence of gypsum and minor goethite, and X-ray scanning shows some turbiditic current structures with rip clasts, crossbedding, and lamina- tions. A fourth high energy sedimentary layer is identified at 158 cm depth (see Fig. S2-1). It is characterized by pale brown silty clay, with broken shell fragments and extremely poor sorting, and with a high peak of magnetic susceptibility at the base of the ...
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... 2. As shown in ( Fig. S2-2), the core is ∼ 90 cm deep and located ∼ 264 m from the shoreline (Fig. 2b). Two high energy sedimentary layers are identified. The first layer is a ∼ 12 cm thick brown clay sediments at ∼ 13 cm depth mixed with gravel and sand. The layer is rich in organic matter (>1 % of dry weight), with a small peak of magnetic suscep- tibility and ...
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... 2. As shown in ( Fig. S2-2), the core is ∼ 90 cm deep and located ∼ 264 m from the shoreline (Fig. 2b). Two high energy sedimentary layers are identified. The first layer is a ∼ 12 cm thick brown clay sediments at ∼ 13 cm depth mixed with gravel and sand. The layer is rich in organic matter (>1 % of dry weight), with a small peak of magnetic suscep- tibility and where the geochemical analysis shows a minor component of goethite. The ...
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... samples were collected below and above the high energy sedimentary layers but, unfortunately, their content did not contain enough carbon for dating. The two shell (gas- tropod) samples collected at 75 and 77 cm depth (well below the lowermost high energy sedimentary layer, Fig. S2-2) have calibrated dates of 32 971-34 681 and 34 362-36 931 BC, re- spectively (Table 2b). These ages may well be due to mixed and/or reworked ...
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... 3. This core located 270 m from the shoreline near the outlet (lowland between high dunes) that allowed tsunami wave inundation (Figs. 2b and S2-3). It revealed three high energy sedimentary layers. The first layer is ∼ 25 cm deep and corresponds to a 26 cm thick pale brown clay character- ized by broken shells fragments and sediments rich in organic matter. The second layer at a ∼ 70 cm depth is 17.5 cm thick and characterized by white sand laminated at the top with a low peak of ...
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... 9 log description with X-ray scanning, lithology log, magnetic susceptibility, mean grain size, sediment sorting, total organic and inorganic matter, and bulk mineralogy. The arrows show the high values of each measurement that may correlate with tsunami deposits. Illustrations of cores 2-12 are in the Supplement. 34 218-37 224 BC, respectively (Fig. S2-3 and Table 2b). These two samples are located within the stratigraphic high energy sedimentary layer 2 and may correspond to reworked sediments due to the high energy sedimentation during the catastrophic ...
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... 4. The core is located 435 m from the shoreline and shows sedimentary units where we identify two high energy sedimentary layers with low magnetic susceptibility (Fig. S2- 4). The first layer (7 cm thick) is a white sand at a ∼ 12.5 cm depth with poorly sorted sediments, broken shell fragments with organic matter >2 % of dry weight of total sediment fraction. The second layer is pale yellow sand at a ∼ 102 to 130 cm depth, characterized by broken shell fragments with a minor amount of illite and ...
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... shell sample collected for dating at a 37 cm depth pro- vides a calibrated date of 32 887-34 447 BC (Table 2b). This sample, located in the stratigraphic high energy sedimentary layer 1, results from high energy reworked sedimentation during the catastrophic event (Fig. ...
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... 5. The core is the southernmost in the El Alamein site, located 490 m from the shoreline (Fig. 2b; Fig. S2-5). The core reaches a depth of 73 cm and the sedimentary suc- cession does not show any catastrophic sedimentary layer of high energy sedimentary origin. According to its content, core 5 may show the limit of the inundation area with re- spect to at least the first and second high energy sedimentary ...
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... 6: This core is located south of the sand dunes, 320 m from the shoreline (Fig. 2b). It is characterized by three high energy sedimentary layers (Fig. S2-6). The first layer is a ∼ 24 cm thick pale yellow sand with broken shells fragments (between a 5 and 26 cm depth) and poorly sorted sediments rich in organic matter (larger than 2.5 % of dry weight). The second layer (∼ 18.5 cm thick) at a 50-75 cm depth is ...
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... 6: This core is located south of the sand dunes, 320 m from the shoreline (Fig. 2b). It is characterized by three high energy sedimentary layers (Fig. S2-6). The first layer is a ∼ 24 cm thick pale yellow sand with broken shells fragments (between a 5 and 26 cm depth) and poorly sorted sediments rich in organic matter (larger than 2.5 % of dry weight). The second layer (∼ 18.5 cm thick) at a 50-75 cm depth is characterized by yellow sand with mixed gastropods and bi- valves, and a high ...
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... 441 BC. The second and third samples are coral and charcoal fragments at a ∼ 60 and ∼ 80 cm depth that gave calibrated ages of 42 776-69 225 BC and modern (younger than AD 1650). The first gastropod sample is above the high energy sedimentary layer 2 while the second coral sample was within the stratigraphic high energy sedimentary layer 2 ( Fig. S2-7). These samples may result from mixed sedimentation and reworking due to high current ...
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... 7. This core was located 273 m from the shoreline (Fig. 2b). It is characterized by sedimentary units that may in- clude three high energy sedimentary layers within the 120 cm deep core (Fig. S2-7). The first layer (at a ∼ 14 cm depth) is a 6 cm thick brown sand with broken shell fragments and a considerable amount of cement gypsum with a minor amount of Illite and goethite. It is rich with ...
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... 7. This core was located 273 m from the shoreline (Fig. 2b). It is characterized by sedimentary units that may in- clude three high energy sedimentary layers within the 120 cm deep core (Fig. S2-7). The first layer (at a ∼ 14 cm depth) is a 6 cm thick brown sand with broken shell fragments and a considerable amount of cement gypsum with a minor amount of Illite and goethite. It is rich with organic matter (>2 % of dry weight) of a swampy environment and the notice- able peak of magnetic susceptibility. The second layer at a 50 cm ...
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... 8. This core is located 214 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-8). The first layer is a 16 cm thick pale yellow silty clay at a ∼ 14 cm depth, rich in organic matter, with a minor amount of goethite and bioclasts rich. The second layer (at a ∼ 52 cm depth) is a 22 cm thick pale yellow silty- clay with broken shells, characterized by ...
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... 8. This core is located 214 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-8). The first layer is a 16 cm thick pale yellow silty clay at a ∼ 14 cm depth, rich in organic matter, with a minor amount of goethite and bioclasts rich. The second layer (at a ∼ 52 cm depth) is a 22 cm thick pale yellow silty- clay with broken shells, characterized by a high peak of mag- netic susceptibility and rich in organic matter ...
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... 9. The core is located 130 m from the shore- line. Three high energy sedimentary layers are recognized ( Fig. 5b; Fig. S2-9). The first layer (at a ∼ 16 cm depth) is a 13 cm thick white sand with a high content of organic mat- ter and rip up clasts that appear in X-ray scanning character- ized by highly broken shell fragments. The second layer at a 67 cm depth is 22 cm thick and characterized by white sand, with a peak of magnetic susceptibility, high ...
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... 10. The core is located 245 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-10). The first layer (at a ∼ 19 cm depth) is a 9 cm thick brown silty clay with broken shell fragments, rich in organic matter (>4 % of dry weight) and high peak of magnetic susceptibility; rip up clasts and laminations appear in X-ray scanning. The second layer (38 cm ...
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... 10. The core is located 245 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-10). The first layer (at a ∼ 19 cm depth) is a 9 cm thick brown silty clay with broken shell fragments, rich in organic matter (>4 % of dry weight) and high peak of magnetic susceptibility; rip up clasts and laminations appear in X-ray scanning. The second layer (38 cm thick) is a brown sand at a 48 cm depth with broken fragments of ...
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... 11. The core is located 151 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are rec- ognized ( Fig. S2-11). The first layer is 10 cm thick white sand with broken shell fragments at a ∼ 19 cm depth. The layer shows high magnetic susceptibility, rich organic mat- ter (>4 % of dry weight) with a high percent of gypsum (>50 %). The second layer (at a 76 cm depth) is a 9 cm ...
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... 11. The core is located 151 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are rec- ognized ( Fig. S2-11). The first layer is 10 cm thick white sand with broken shell fragments at a ∼ 19 cm depth. The layer shows high magnetic susceptibility, rich organic mat- ter (>4 % of dry weight) with a high percent of gypsum (>50 %). The second layer (at a 76 cm depth) is a 9 cm thick white sand with broken shell fragments, a high peak of mag- netic ...
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... 12. The core is located 127 m from the shore- line (Fig. 2b). Four high energy sedimentary layers are recognized in section 1 and one high energy sedimentary layer in section 2 (Figs. S2-12a, b). The first layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits, and highly broken gastropods and lamellibranch fossils. The layer is characterized by high value of ...
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... 12. The core is located 127 m from the shore- line (Fig. 2b). Four high energy sedimentary layers are recognized in section 1 and one high energy sedimentary layer in section 2 (Figs. S2-12a, b). The first layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits, and highly broken gastropods and lamellibranch fossils. The layer is characterized by high value of organic matter and low peak magnetic susceptibil- ity. The second layer is ∼ 13 cm thick white sandy deposits intercalated with coarse ...
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... cm thick grey sandy clay at 89 cm depth, with laminations at the bottom of the deposit, vertically aligned gastropods, broken shell fragments, rich in total organic matter and a low peak of magnetic susceptibil- ity. A fourth high energy sedimentary layer of medium to fine pale yellow sand, with broken shell fragments, is identified in section 2 (Fig. S2-12b) at a 151 cm depth. It is characterized by poor sorting, low peak of magnetic susceptibility, a large amount of organic matter (>5.5 % of dry weight) and high amount of ...
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... cores and trenches in both Kefr Saber and El Alamein sites expose three main layers characterized by fine and coarse sand mixed with bioclasts. We assume these indicate the occurrence of high energy and catastrophic sedimentary deposits in the coastal lagoon environment (Figs. 2a, b, c, and 3). Although the two studied sites are ∼ 200 km apart, a white sandy layer with broken shells is found in all trenches (see Figs. 3 and S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units ...
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... these indicate the occurrence of high energy and catastrophic sedimentary deposits in the coastal lagoon environment (Figs. 2a, b, c, and 3). Although the two studied sites are ∼ 200 km apart, a white sandy layer with broken shells is found in all trenches (see Figs. 3 and S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units mixed with gravel and broken shells that become finer-grained and thinner landward (see trench P4, Fig. 3) or disappear when distant from the shore (core 5, Fig. S2-5). The high energy sedimentary characteristics within four ...
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... the occurrence of high energy and catastrophic sedimentary deposits in the coastal lagoon environment (Figs. 2a, b, c, and 3). Although the two studied sites are ∼ 200 km apart, a white sandy layer with broken shells is found in all trenches (see Figs. 3 and S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units mixed with gravel and broken shells that become finer-grained and thinner landward (see trench P4, Fig. 3) or disappear when distant from the shore (core 5, Fig. S2-5). The high energy sedimentary characteristics within four layers in the ∼ 2 m ...
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... S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units mixed with gravel and broken shells that become finer-grained and thinner landward (see trench P4, Fig. 3) or disappear when distant from the shore (core 5, Fig. S2-5). The high energy sedimentary characteristics within four layers in the ∼ 2 m thick sedimentary units sug- gest that these layers are tsunami deposits rather than storm ...
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... most cores (Figs. 5a, b, and from Fig. S2-1 to Fig. S2- 12), the first tsunami layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits with bro- ken gastropods and lamellibranch (shell) fossils. This layer is characterized by bi-modal grain size distribution with high value of organic matter and low peak of magnetic suscepti- bility with a rich ...
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... most cores (Figs. 5a, b, and from Fig. S2-1 to Fig. S2- 12), the first tsunami layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits with bro- ken gastropods and lamellibranch (shell) fossils. This layer is characterized by bi-modal grain size distribution with high value of organic matter and low peak of magnetic suscepti- bility with a rich content in ...
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... event is also reported during the 24 June 1870 earthquake (M w 7-7.5), but despite some de- bates on its occurrence, the inundation of the Alexandria har- bour leaves no doubts about the tsunami waves on the Egyp- tian coastline (see Sect. 2). Figure 7. Depth distribution of tsunami layers in cores at the El Alamein site (see core locations in Fig. 2b). The depth correlation of paleotsunami layers indicates the consistent succession of deposits in the lagoon. Deposits of layers 1, 2, and 3 are related with tsunami events AD 1870, AD 1303 and AD 365 of the eastern Mediterranean Sea (see Fig. 6 and Table 1). Layer 4 corresponds to tsunami event 1491-1951 BC and is not reported in ...
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... that are mostly composed of oolitic grains ( Frihy et al., 2010). The beach-dune ridge is developed along the receding Quaternary shorelines and embayment of the Mediterranean Sea (Hassouba, 1995). Coastal dune-ridges protect inner la- goons from the sea and constitute outstanding landform fea- tures at several locations parallel to the shoreline (Fig. 2). When the sand dunes are removed they leave rocky head- land outcrops ( Abbas et al., 2008). The 2-20 m-high coastal beach-dune ridges are mainly composed of oolitic and bio- genic calcareous sand and separate the coastal lagoons and sabkhas (salt water) from the sea. The lagoons with flat de- pressions separated from the sea by the ...
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... the lagoon. Two sites (∼ 200 km part) within seasonally dry lagoons have met the selection criteria for paleotsunami investigation (Figs. 1 and 2): (1) Kefr Saber located ∼ 32 km west of Marsa-Matrouh city; and (2) the El Alamein site, ∼ 10 km northwest of El Alamein city and ∼ 150 km west of Alexandria. Five trenches were dug at Kefr Saber ( Fig. 2a), and 12 cores taken at the El Alamein site (Fig. ...
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... dry lagoons have met the selection criteria for paleotsunami investigation (Figs. 1 and 2): (1) Kefr Saber located ∼ 32 km west of Marsa-Matrouh city; and (2) the El Alamein site, ∼ 10 km northwest of El Alamein city and ∼ 150 km west of Alexandria. Five trenches were dug at Kefr Saber ( Fig. 2a), and 12 cores taken at the El Alamein site (Fig. ...
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... 12 cores extend between 1 and 2.6 m depth. Except, for cores 1 and 9, which are shown in Fig. 5a and b, the detailed stratigraphic logs and related measurements are presented in Fig. S2. In a previous reconnaissance field investigation, a coarse and fine white sand layer was identified at ∼ 30 cm below the surface in a test pit. Two charcoal samples El Al sa1 and El Al sa2 collected at a 25 and 56 cm depth gave ages of AD 1680-1908and AD 1661-1931, respectively. The de- scription of cores is as ...
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... 1. This core is located ∼ 166 m from the shore- line (Fig. 2b) ∼ 2.14 m and the stratigraphic section includes four high en- ergy sedimentary layers recognized as follows (Fig. 5a, sec- tion 1 of core 1 and its continuation at depth in Fig. ...
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... 1. This core is located ∼ 166 m from the shore- line (Fig. 2b) ∼ 2.14 m and the stratigraphic section includes four high en- ergy sedimentary layers recognized as follows (Fig. 5a, sec- tion 1 of core 1 and its continuation at depth in Fig. ...
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... yellow sand with poor sort- ing of sediments, and a high peak in magnetic susceptibility. The chemical analysis shows the presence of gypsum and minor goethite, and X-ray scanning shows some turbiditic current structures with rip clasts, crossbedding, and lamina- tions. A fourth high energy sedimentary layer is identified at 158 cm depth (see Fig. S2-1). It is characterized by pale brown silty clay, with broken shell fragments and extremely poor sorting, and with a high peak of magnetic susceptibility at the base of the ...
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... 2. As shown in ( Fig. S2-2), the core is ∼ 90 cm deep and located ∼ 264 m from the shoreline (Fig. 2b). Two high energy sedimentary layers are identified. The first layer is a ∼ 12 cm thick brown clay sediments at ∼ 13 cm depth mixed with gravel and sand. The layer is rich in organic matter (>1 % of dry weight), with a small peak of magnetic suscep- tibility and ...
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... 2. As shown in ( Fig. S2-2), the core is ∼ 90 cm deep and located ∼ 264 m from the shoreline (Fig. 2b). Two high energy sedimentary layers are identified. The first layer is a ∼ 12 cm thick brown clay sediments at ∼ 13 cm depth mixed with gravel and sand. The layer is rich in organic matter (>1 % of dry weight), with a small peak of magnetic suscep- tibility and where the geochemical analysis shows a minor component of goethite. The ...
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... samples were collected below and above the high energy sedimentary layers but, unfortunately, their content did not contain enough carbon for dating. The two shell (gas- tropod) samples collected at 75 and 77 cm depth (well below the lowermost high energy sedimentary layer, Fig. S2-2) have calibrated dates of 32 971-34 681 and 34 362-36 931 BC, re- spectively (Table 2b). These ages may well be due to mixed and/or reworked ...
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... 3. This core located 270 m from the shoreline near the outlet (lowland between high dunes) that allowed tsunami wave inundation (Figs. 2b and S2-3). It revealed three high energy sedimentary layers. The first layer is ∼ 25 cm deep and corresponds to a 26 cm thick pale brown clay character- ized by broken shells fragments and sediments rich in organic matter. The second layer at a ∼ 70 cm depth is 17.5 cm thick and characterized by white sand laminated at the top with a low peak of ...
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... 9 log description with X-ray scanning, lithology log, magnetic susceptibility, mean grain size, sediment sorting, total organic and inorganic matter, and bulk mineralogy. The arrows show the high values of each measurement that may correlate with tsunami deposits. Illustrations of cores 2-12 are in the Supplement. 34 218-37 224 BC, respectively (Fig. S2-3 and Table 2b). These two samples are located within the stratigraphic high energy sedimentary layer 2 and may correspond to reworked sediments due to the high energy sedimentation during the catastrophic ...
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... 4. The core is located 435 m from the shoreline and shows sedimentary units where we identify two high energy sedimentary layers with low magnetic susceptibility (Fig. S2- 4). The first layer (7 cm thick) is a white sand at a ∼ 12.5 cm depth with poorly sorted sediments, broken shell fragments with organic matter >2 % of dry weight of total sediment fraction. The second layer is pale yellow sand at a ∼ 102 to 130 cm depth, characterized by broken shell fragments with a minor amount of illite and ...
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... shell sample collected for dating at a 37 cm depth pro- vides a calibrated date of 32 887-34 447 BC (Table 2b). This sample, located in the stratigraphic high energy sedimentary layer 1, results from high energy reworked sedimentation during the catastrophic event (Fig. ...
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... 5. The core is the southernmost in the El Alamein site, located 490 m from the shoreline (Fig. 2b; Fig. S2-5). The core reaches a depth of 73 cm and the sedimentary suc- cession does not show any catastrophic sedimentary layer of high energy sedimentary origin. According to its content, core 5 may show the limit of the inundation area with re- spect to at least the first and second high energy sedimentary ...
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... 6: This core is located south of the sand dunes, 320 m from the shoreline (Fig. 2b). It is characterized by three high energy sedimentary layers (Fig. S2-6). The first layer is a ∼ 24 cm thick pale yellow sand with broken shells fragments (between a 5 and 26 cm depth) and poorly sorted sediments rich in organic matter (larger than 2.5 % of dry weight). The second layer (∼ 18.5 cm thick) at a 50-75 cm depth is ...
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... 6: This core is located south of the sand dunes, 320 m from the shoreline (Fig. 2b). It is characterized by three high energy sedimentary layers (Fig. S2-6). The first layer is a ∼ 24 cm thick pale yellow sand with broken shells fragments (between a 5 and 26 cm depth) and poorly sorted sediments rich in organic matter (larger than 2.5 % of dry weight). The second layer (∼ 18.5 cm thick) at a 50-75 cm depth is characterized by yellow sand with mixed gastropods and bi- valves, and a high ...
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... 441 BC. The second and third samples are coral and charcoal fragments at a ∼ 60 and ∼ 80 cm depth that gave calibrated ages of 42 776-69 225 BC and modern (younger than AD 1650). The first gastropod sample is above the high energy sedimentary layer 2 while the second coral sample was within the stratigraphic high energy sedimentary layer 2 ( Fig. S2-7). These samples may result from mixed sedimentation and reworking due to high current ...
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... 7. This core was located 273 m from the shoreline (Fig. 2b). It is characterized by sedimentary units that may in- clude three high energy sedimentary layers within the 120 cm deep core (Fig. S2-7). The first layer (at a ∼ 14 cm depth) is a 6 cm thick brown sand with broken shell fragments and a considerable amount of cement gypsum with a minor amount of Illite and goethite. It is rich with ...
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... 7. This core was located 273 m from the shoreline (Fig. 2b). It is characterized by sedimentary units that may in- clude three high energy sedimentary layers within the 120 cm deep core (Fig. S2-7). The first layer (at a ∼ 14 cm depth) is a 6 cm thick brown sand with broken shell fragments and a considerable amount of cement gypsum with a minor amount of Illite and goethite. It is rich with organic matter (>2 % of dry weight) of a swampy environment and the notice- able peak of magnetic susceptibility. The second layer at a 50 cm ...
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... 8. This core is located 214 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-8). The first layer is a 16 cm thick pale yellow silty clay at a ∼ 14 cm depth, rich in organic matter, with a minor amount of goethite and bioclasts rich. The second layer (at a ∼ 52 cm depth) is a 22 cm thick pale yellow silty- clay with broken shells, characterized by ...
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... 8. This core is located 214 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-8). The first layer is a 16 cm thick pale yellow silty clay at a ∼ 14 cm depth, rich in organic matter, with a minor amount of goethite and bioclasts rich. The second layer (at a ∼ 52 cm depth) is a 22 cm thick pale yellow silty- clay with broken shells, characterized by a high peak of mag- netic susceptibility and rich in organic matter ...
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... 9. The core is located 130 m from the shore- line. Three high energy sedimentary layers are recognized ( Fig. 5b; Fig. S2-9). The first layer (at a ∼ 16 cm depth) is a 13 cm thick white sand with a high content of organic mat- ter and rip up clasts that appear in X-ray scanning character- ized by highly broken shell fragments. The second layer at a 67 cm depth is 22 cm thick and characterized by white sand, with a peak of magnetic susceptibility, high ...
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... 10. The core is located 245 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-10). The first layer (at a ∼ 19 cm depth) is a 9 cm thick brown silty clay with broken shell fragments, rich in organic matter (>4 % of dry weight) and high peak of magnetic susceptibility; rip up clasts and laminations appear in X-ray scanning. The second layer (38 cm ...
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... 10. The core is located 245 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are recog- nized ( Fig. S2-10). The first layer (at a ∼ 19 cm depth) is a 9 cm thick brown silty clay with broken shell fragments, rich in organic matter (>4 % of dry weight) and high peak of magnetic susceptibility; rip up clasts and laminations appear in X-ray scanning. The second layer (38 cm thick) is a brown sand at a 48 cm depth with broken fragments of ...
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... 11. The core is located 151 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are rec- ognized ( Fig. S2-11). The first layer is 10 cm thick white sand with broken shell fragments at a ∼ 19 cm depth. The layer shows high magnetic susceptibility, rich organic mat- ter (>4 % of dry weight) with a high percent of gypsum (>50 %). The second layer (at a 76 cm depth) is a 9 cm ...
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... 11. The core is located 151 m from the shoreline (Fig. 2b). Three high energy sedimentary layers are rec- ognized ( Fig. S2-11). The first layer is 10 cm thick white sand with broken shell fragments at a ∼ 19 cm depth. The layer shows high magnetic susceptibility, rich organic mat- ter (>4 % of dry weight) with a high percent of gypsum (>50 %). The second layer (at a 76 cm depth) is a 9 cm thick white sand with broken shell fragments, a high peak of mag- netic ...
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... 12. The core is located 127 m from the shore- line (Fig. 2b). Four high energy sedimentary layers are recognized in section 1 and one high energy sedimentary layer in section 2 (Figs. S2-12a, b). The first layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits, and highly broken gastropods and lamellibranch fossils. The layer is characterized by high value of ...
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... 12. The core is located 127 m from the shore- line (Fig. 2b). Four high energy sedimentary layers are recognized in section 1 and one high energy sedimentary layer in section 2 (Figs. S2-12a, b). The first layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits, and highly broken gastropods and lamellibranch fossils. The layer is characterized by high value of organic matter and low peak magnetic susceptibil- ity. The second layer is ∼ 13 cm thick white sandy deposits intercalated with coarse ...
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... cm thick grey sandy clay at 89 cm depth, with laminations at the bottom of the deposit, vertically aligned gastropods, broken shell fragments, rich in total organic matter and a low peak of magnetic susceptibil- ity. A fourth high energy sedimentary layer of medium to fine pale yellow sand, with broken shell fragments, is identified in section 2 (Fig. S2-12b) at a 151 cm depth. It is characterized by poor sorting, low peak of magnetic susceptibility, a large amount of organic matter (>5.5 % of dry weight) and high amount of ...
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... cores and trenches in both Kefr Saber and El Alamein sites expose three main layers characterized by fine and coarse sand mixed with bioclasts. We assume these indicate the occurrence of high energy and catastrophic sedimentary deposits in the coastal lagoon environment (Figs. 2a, b, c, and 3). Although the two studied sites are ∼ 200 km apart, a white sandy layer with broken shells is found in all trenches (see Figs. 3 and S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units ...
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... these indicate the occurrence of high energy and catastrophic sedimentary deposits in the coastal lagoon environment (Figs. 2a, b, c, and 3). Although the two studied sites are ∼ 200 km apart, a white sandy layer with broken shells is found in all trenches (see Figs. 3 and S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units mixed with gravel and broken shells that become finer-grained and thinner landward (see trench P4, Fig. 3) or disappear when distant from the shore (core 5, Fig. S2-5). The high energy sedimentary characteristics within four ...
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... the occurrence of high energy and catastrophic sedimentary deposits in the coastal lagoon environment (Figs. 2a, b, c, and 3). Although the two studied sites are ∼ 200 km apart, a white sandy layer with broken shells is found in all trenches (see Figs. 3 and S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units mixed with gravel and broken shells that become finer-grained and thinner landward (see trench P4, Fig. 3) or disappear when distant from the shore (core 5, Fig. S2-5). The high energy sedimentary characteristics within four layers in the ∼ 2 m ...
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... S1a, b, c, d, e) and cores (except for core 5, see Figs. 5a, b and from Fig. S2-1 to Fig. S2-12.). The recurrent white sandy deposits in trenches and cores is visi- ble as coarse sand units mixed with gravel and broken shells that become finer-grained and thinner landward (see trench P4, Fig. 3) or disappear when distant from the shore (core 5, Fig. S2-5). The high energy sedimentary characteristics within four layers in the ∼ 2 m thick sedimentary units sug- gest that these layers are tsunami deposits rather than storm ...
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... most cores (Figs. 5a, b, and from Fig. S2-1 to Fig. S2- 12), the first tsunami layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits with bro- ken gastropods and lamellibranch (shell) fossils. This layer is characterized by bi-modal grain size distribution with high value of organic matter and low peak of magnetic suscepti- bility with a rich ...
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... most cores (Figs. 5a, b, and from Fig. S2-1 to Fig. S2- 12), the first tsunami layer is ∼ 7.5 cm thick at ∼ 19 cm depth and is made of poorly sorted white sandy deposits with bro- ken gastropods and lamellibranch (shell) fossils. This layer is characterized by bi-modal grain size distribution with high value of organic matter and low peak of magnetic suscepti- bility with a rich content in ...
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... event is also reported during the 24 June 1870 earthquake (M w 7-7.5), but despite some de- bates on its occurrence, the inundation of the Alexandria har- bour leaves no doubts about the tsunami waves on the Egyp- tian coastline (see Sect. 2). Figure 7. Depth distribution of tsunami layers in cores at the El Alamein site (see core locations in Fig. 2b). The depth correlation of paleotsunami layers indicates the consistent succession of deposits in the lagoon. Deposits of layers 1, 2, and 3 are related with tsunami events AD 1870, AD 1303 and AD 365 of the eastern Mediterranean Sea (see Fig. 6 and Table 1). Layer 4 corresponds to tsunami event 1491-1951 BC and is not reported in ...
Similar publications
We present new data on the Loukkos estuary in Larache combining analysis of several historical maps of the area before and after AD 1755 and field observations. The historical maps show an abrupt change of the Loukkos estuary between 1668 and 1774, while sedimentological analysis of the first meter of 5 cores taken in different points of the Loukko...
Citations
... The documentation of high-energy/tsunami events is also possible by means of geochemical sediment proxies, in particular high concentration values of marine elements such as Ca, Cl, Sr and Ti (Judd et al. 2017;Moreira et al. 2017) and terrigenous elements (Zr, Fe, Ti, Al, Si, K, and Fe/Ti;Chagué-Goff et al. 2002;Wedepohl 1971). Tsunami deposits have been identified and described from both prehistoric and historical coastal sedimentary sequences in Italy (Mastronuzzi and Sansò 2004), Spain (Kelletat et al. 2005), Morocco (Basquin et al. 2023) and along the eastern Mediterranean coasts (Greece: Scheffers and Scheffers 2007; Cyprus: Kelletat and Schellmann 2002; and the Hellenic zone: Salama et al. 2018). ...
... Along the southern Mediterranean coast, Papadopoulos (2009) compiled historical data on tsunamis that affected the Algerian coast in 1365, 1773, 1856, 1954and 1980 Along the Alexandria coastline (Egypt), multiproxy analyses of sediments in trenches and cores show correlations with tsunamigenic earthquakes in 1600 BC and in 365 and 1303 AD as well as the 1870 AD Hellenic zone event (Salama et al. 2018). Based on geophysical surveys and sediment core analysis from the Ionian Sea, Polonia et al. (2013) showed that the 20-to 25-m-thick megaturbidite was triggered by the 365 CE Cretan earthquake and tsunami. ...
In this paper, sedimentological, geochemical, palaeontological and radiocarbon dating results from Holocene cores are presented to infer the palaeoenvironmental evolution of the Thyna coast in the Gulf of Gabes (Tunisia). Based on detailed faunal, sedimentological and geochemical analyses, the evolution of the coastline and the impact of a high-energy event around 365 CE which led to the destruction of parts of the historic city of Thyna are reconstructed. The scenario developed here is based on the analysis of four drill cores and shows an evolution from a shallow marine palaeoenvironment to a gradually enclosed lagoon. The core record includes the following. (i) Evidence of the first Holocene transgression at around 6234–5733 cal year BCE (8184–7683 cal yr BP), characterised by the first appearance of foraminifera and molluscs. The transgressive sediments of the first transgression overlie the Upper Pleistocene–Greenlandian terrigenous clays. (ii) Deposits of a high-energy event that formed in the fourth century after the Crete earthquake (365 AD). The bioclastic deposits are characterised by an erosive base and are rich in rip-up clasts, charcoal particles, wood and pottery fragments, and abundant shell debris. This deposit comprises a blend of remains from coastal and lagoonal molluscs, along with brackish foraminifera originating from the more internal regions of a confined lagoon. (iii) After the high-energy event, there is evidence of a partially open lagoon off the coast, which was protected from the open sea by a sand barrier. (iv) Evidence of increased marine influence and further opening of the lagoon in the nineteenth and twentieth centuries, suggesting that the coastal area of Thyna is affected not only by the current sea level rise but probably also by subsidence. The scenario developed and the events identified here are compared with those already known.
... At the same time several research articles have warrned about the potential exposure of several coastal locations in the EM basin to tsunamis triggered A.D. 365 Crete earthquake/tsunami (Shaw et al., 2008;Hamouda 2010a; H.M. El-Asmar et al. The Egyptian Journal of Remote Sensing and Space Sciences 27 (2024) [147][148][149][150][151][152][153][154][155][156][157][158][159][160][161][162][163][164] 2010b; Ozel et al., 2011;England et al., 2015;Polonia et al., 2013Polonia et al., , 2016Salama et al., 2018;Rosi et al., 2019;Yavuz et al., 2020;Evelpidou et al., 2021). These studies recorded several EM coastlines are vulnerable to tsunamigenic earthquakes with tectonic uplifting, land sliding or liquefaction. ...
... The pumice occurrence was recorded among historical tsunami deposits hitting Egypt (Salama et al., 2018, Steinhauser et al., 2010, and other global parts (Ş ahoglu et al., 2022;Huber et al., 2003). The historical tsunamis are generated by earthquakes of magnitudes of Mw ≥7 to 8.5 (England et al., 2015, Ott et al., 2021 similar to the present KMTE. ...
From the 6th to 7th of February 2023, a storm surge struck Ras El-Bar, Nile Delta coast and attacked the resort facilities, with a wave height and velocity in deep water of 7.2 m and 12.7 m/sec respectively. The wind speed was 12.84 m/s, blowing from the NW and the WSW quadrants. This was an unwitnessed event revealed from the study of similar time interval from 1998 to 2022. Synchronizing with this event on the 6th of February 2023, was Kahramanmaras¸ Turkey Earthquakes. Consequently, the shoreline receded for about − 30 m and with a drop in sea-level of about − 40 cm. Furthermore, considerable changes in the beach morphology from a dissipative to a cuspate-related, intermediate tidal flat transverse bar with a rip profile. These are either related to the change in the morphodynamic or sedimentary budget, and resulting due to seawater scouring of bottom sediments for more than − 30 cm. Two days preceding the Earthquakes an isostatic rise in sea-level (+20 cm) at the Turkish coast compared to the Mediterranean records, which is interpreted due to regional underwater seismic activities. The drop in the sea-surface height does not happen due to seawater outflow to the Atlantic Ocean. However, the sealevel regained its normal position because of the refill occurring from the Atlantic Ocean to the Mediterranean Sea. The pumice pieces, organic peat, and starfish distributed at Ras El-Bar coast, and thrown from the Northern Mediterranean indicate that the Egyptian coast was subjected to a little tsunami with average height of 14 cm. It is minimized due to enforced wave shifting from high pressure over Egypt to the low-pressure sinks.
... Research topics for 2011-2023 also evolved towards risk assessment of infrastructure and building resilience to earthquake and tsunami disasters, characterized by the emergence of the keyword building vulnerability, which previously was not present in the 2000-2010 publications (Batzakis et al. 2020;Triantafyllou et al. 2019). Although the scope of research topics for 2011-2023 has expanded, topics related to rupture fault analysis, paleotsunami sediment analysis, and tsunami wave propagation modeling continue to emerge and develop (Laksono 2023;Nemati et al. 2019;Salama et al. 2018) because these topics are classified as motor themes based on the strategic diagram (Fig. 16A). In the future, topics classified as motor themes such as seismic hazard, which have high centrality and density, will continue to thrive because they are relevant to other topics (Cobo et al. 2012;Mishra et al. 2023) such as seismoturbidite, active-faults, historical earthquakes, tsunami modeling, sedimentary-feature, and catalog (Fig. 16B). ...
Background
The Mediterranean Sea is a region characterized by high seismic activity, with at least 200 tsunami events recorded from the fourth century to the present twenty-first century. Numerous studies have been conducted to understand past tsunami events, earthquake–tsunami generation, tsunami recurrence periods, tsunami vulnerability zones, and tsunami hazard mitigation strategies. Therefore, gaining insights into future trends and opportunities in Mediterranean Sea tsunami research is crucial for significantly contributing to all relevant aspects. This study aims to assess such trends and opportunities through a scientometric analysis of publications indexed by Web of Science from 2000 to 2023.
Results
Based on a selection of 329 publications, including research articles, review articles, book chapters, and conference papers, published between 2000 and 2023, Italy has the highest number of publications and citations in this field. The number of publications has increased significantly, especially after the 2004 Indian Ocean, 2011 Tohoku, and 2018 Palu tsunamis. According to the keyword analysis, the terms “tsunami”, “earthquake”, “hazard”, “wave”, “Mediterranean”, “coast”, and “tectonic” were the most frequently used in these publications. Research themes consist of four classifications: motor themes, such as seismic hazard; specific but well-developed themes, like tsunamiite; emerging or disappearing themes, for example, climate change; and general or basic themes, such as equations and megaturbidite. The number of publications related to the motor theme classification continued to grow throughout 2000–2023. Topics from 2011–2023 are more complex compared to 2000–2010, characterized by the emergence of new keywords such as evacuation planning, risk reduction, risk mitigation, building vulnerability, coastal vulnerability, climate change, probabilistic tsunami hazard assessment (PTVA-3 and PTVA-4). However, topics that were popular in the 2000–2010 period (e.g., paleotsunami deposits, earthquake, and tsunami propagation analysis) also increased in 2011–2023.
Conclusions
Research topics with high centrality and density such as seismic hazard will continue to develop and prospect. The cluster network of this topic includes seismoturbidites, sedimentary features, tsunami modeling, active faults, catalog, and historical earthquakes.
... However, the thickness of T5 is an order of magnitude larger relative to T1 and all other turbidites, suggesting that T5 is related to an exceptional event. The CE 365 catastrophic Crete earthquake produced a tsunami with basin-wide effects, from Egypt (Salama et al., 2018), to Sicily (Smedile et al., 2011), Malta (Mottershead et al., 2018) and Tunisia (Bahrouni et al., 2022). For this reason, we propose that T5 is related to the CE 365 megatsunami originated in the Hellenic Arc. ...
... The 365 and 1303 CE earthquake tsunamis are the most investigated scenarios mainly due to their vast effects and well-known severity as they caused catastrophic and basin-wide impacts across the EMB. These large events are well-documented and preserved in the written historical reports, morphological, and geological traces as well (Soloviev et al. 2000;Ambraseys and Synolakis 2010;Shah-Hosseini et al. 2016;Salama et al. 2018). A recently accomplished geomorphologic study for the Egyptian coast of the Mediterranean carried out by Torab and Dalal (2015) has suggested that the presence of oriented huge boulders was deposited by either paleo-tsunami mega waves or by sea waves during winter storms. ...
... The compilation and update efforts of complete, long, accurate, and homogeneous tsunamigenic earthquake catalogue for the EMB as much as possible have begun since several decades and still going on (Galanopoulos 1960;Ambraseys 1962;Antonopoulos 1979;Papadopoulos & Chalkis 1984;Tinti and Maramai 1996;Soloviev et al. 2000;Papadopoulos & Fokaefs 2005; TRANSFER project 2009 (Tsunami Risk and Strategies For the European Region); Ambraseys and Synolakis 2010; Papadopoulos et al. 2014). These tsunami catalogues were revisited several times by experts with the latest findings from in the historical documents, field surveys, newly uncovered geological evidence, and paleotsunami studies, e.g., Salama et al. (2018) and Papadopoulos et al. (2014). A list of well-known confirmed large tsunamigenic earthquakes in the area of influence (i.e., EMB) is listed in Table 2. ...
In this research, we have compiled a catalogue of the worst tsunami earthquakes that caused destruction and losses in the northern coastal region of Egypt. Variability in seismic source parameters reflects the level of cognitive uncertainty that exists because most of these destructive tsunamis, if not all, occurred in the pre-instrumental period. We also synthesized a set of hypothetical tsunamis constrained by seismotectonic knowledge of the area of influence to embrace the uncertainty. We also collected the topo-bathymetry information available to make a simulation on the scale of the Egyptian north coast. The multiple scenarios were computed considering references and hypothetical scenarios, and results were presented in maps and tables for wave heights, inundation depth, and estimated arrivals. Comparisons were made between the results calculated in this study and those from previous studies. These were done to identify and measure the reasons for the difference and similarities. The results may contribute to developing risk reduction strategies and a national early warning system. Variability in tsunami intensity measures is prepared for the hypothetical scenarios due to the difference in the fault’s magnitude, location, and geometry. Also, for the first time, temporally based scenarios the sea-level rise and delta sinking were considered in order to highlight the importance of multi-risk analysis for the region of interest. The insight on incorporating other hazards of the temporal resolution indicates a significant increase in inundated areas and wave height. Therefore, proper and detailed estimation of multi-hazard maps for the coastal region of the Nile Delta is highly required to protect the ongoing sustainable development and protect the people and their assets.
... As far as Egypt is concerned, the available tsunami databases indicate that the most hazardous known tsunamigenic earthquakes, which affected the Egyptian coastline, are: the 365 CE (Common Era) Crete earthquake of Mw8.5, the 1222 CE Cyprus earthquake of Mw7.5, and the 1303 CE Rhodes island earthquake of Mw8.0. These tsunamigenic earthquakes were reported to cause destruction and victims along the Egyptian coastline, as evidenced by the available historical reports (e.g., Ambraseys 1962Ambraseys , 2009Ambraseys and Synolakis 2010) and recently published geomorphologic and paleo-tsunami evidence (Shah-Hosseini et al. 2016;Salama et al. 2018). In a recent study by Salama et al. (2018), the age of samples collected from perturbed thin sedimentary units on the Egyptian northern coast correlates with June 24, 1870, August 8, 1303, and July 21, 365 CE, large tsunamigenic earthquakes, thus confirming the historical information of the impact on northern Egypt shoreline. ...
... These tsunamigenic earthquakes were reported to cause destruction and victims along the Egyptian coastline, as evidenced by the available historical reports (e.g., Ambraseys 1962Ambraseys , 2009Ambraseys and Synolakis 2010) and recently published geomorphologic and paleo-tsunami evidence (Shah-Hosseini et al. 2016;Salama et al. 2018). In a recent study by Salama et al. (2018), the age of samples collected from perturbed thin sedimentary units on the Egyptian northern coast correlates with June 24, 1870, August 8, 1303, and July 21, 365 CE, large tsunamigenic earthquakes, thus confirming the historical information of the impact on northern Egypt shoreline. In addition, recent tsunami hazard studies, based on either probabilistic assessment (2475 year return period) or numerical simulation (e.g., Basili et al. 2021-TSU-MAPS-NEAM http:// www. ...
... Several researchers have already modelled tsunamis in the EMB; however, a clear verification step, performed by comparing assumptions and results to available observations on the actual inundation heights and limits, is generally missing. A sedimentary record of past tsunamis along the coastal area west of Alexandria was studied by Salama et al. (2018). The radiocarbon age dating of sedimentary units that may be deposited by tsunami events well correlates with June 24, 1870, CE (Mw 7.5), August 8, 1303, CE (Mw ~ 8), and July 21, 365 CE (Mw 8-8.5) large tsunamigenic earthquakes, which caused inundation in Alexandria and along the northern Egyptian coast. ...
Egypt’s northern coast can be considered a dynamic natural system like several coastal regions worldwide. While it provides many opportunities and resources, it may also pose significant challenges to the community, as the area is prone to land and marine-related geohazards (e.g., earthquakes, sea-level rise, land subsidence, storms, coastal erosion, and tsunamis). Also, the recent national census survey indicates that numerous assets, systems, infrastructures, and cultural heritage sites (elements under risk) are situated within the zone of hazards. Multi-hazard and risk assessments are therefore necessary to achieve national sustainable development plans. This study, in particular, focuses on tsunami hazard, which is defined here as the envelope (upper bound estimate) from a comprehensive set of possible simulated tsunami scenarios. The main aim of this work is to provide robust and conservative hazard estimates while considering the variability related to earthquake parameters. The seismological parameters that describe each tsunamigenic earthquake scenario are extracted from published works. Also, detailed nested grids of topo-bathymetry are developed from free-access data sources. The seismological and topo-bathymetry data are essential components for separately carrying out tsunami modelling for each individual scenario. The simulated scenarios are aggregated to build tsunami intensity maps of interest. The ETAs (Expected Time of Arrival), the maximum, average, and standard deviation of coastal tsunami wave height and the inundation maps are developed based on an aggregated scenario. In addition, the simulation of tsunami wave propagation can provide synthetic mareographs computed at selected sites, which can be used for detailed site-specific analysis. The obtained results from the current work indicate that the northern Egyptian coast is characterized by a moderate-to-high tsunami hazard. The western part of this coast poses the maximum coastal tsunami wave heights; however, the longitudinal dunes, extending parallel to the shoreline, form a natural barrier that reduces the tsunami hazard. In contrast, the central and eastern parts of the Nile Delta and the entrance of the Suez Canal show relatively lower tsunami amplitude but a large inundation because of its low altitude and flat topography that could pose a higher risk to this area. The relatively high exposure and high vulnerability of elements under threat along the northern coast of Egypt may dramatically increase the future risk. It is critical to incorporate these results into a broader multi-hazard and risk assessment to effectively mitigate the impact of natural disasters on the Egyptian-Mediterranean coast.
... Stiros 2010;Pagnoni et al. 2015;Hassan et al. 2020). These tsunamigenic earthquakes have been reported to cause destruction and death along the Egyptian coastline, as evidenced by the available historical reports (Ambraseys et al. 1995;Ambraseys 2009) and recently published geomorphologic and paleo-tsunami evidence (Shah-Hosseini et al. 2016;Salama et al. 2018). The age of samples collected from perturbed thin sedimentary units on the Egyptian northern coast correlated with June 24, 1870, August 8, 1303, and July 21, 365 large tsunamigenic earthquakes, confirming historical information of strong impact on the northern Egypt shoreline (Salama et al. 2018). ...
... These tsunamigenic earthquakes have been reported to cause destruction and death along the Egyptian coastline, as evidenced by the available historical reports (Ambraseys et al. 1995;Ambraseys 2009) and recently published geomorphologic and paleo-tsunami evidence (Shah-Hosseini et al. 2016;Salama et al. 2018). The age of samples collected from perturbed thin sedimentary units on the Egyptian northern coast correlated with June 24, 1870, August 8, 1303, and July 21, 365 large tsunamigenic earthquakes, confirming historical information of strong impact on the northern Egypt shoreline (Salama et al. 2018). In addition, recent tsunami hazard studies based on either probabilistic tsunami hazard assessment (Basili et al. 2018) or numerical tsunami scenarios (e.g. ...
At 12:51 UTC on May 2nd, 2020, an offshore earthquake of magnitude Mw = 6.7 and focal depth of around 10 km occurred south of the island of Crete (Greece). The initial tsunami alert message (TAMs) received by the Egyptian National Research Institute of Astronomy and Geophysics—NRIAG (i.e. the National Tsunami Warning Focal Point for Egypt) was issued by the Geodynamic Institute of the National Observatory of Athens (NOA-HLNTWC), and was based on preliminary, a rather inaccurate hypocenter and magnitude estimates. About 36 min after the earthquake, a follow-up message with an increased tsunami warning level was issued; the updated warning was motivated by a significant revision of hypocenter and magnitude estimates rather than on standard incoming sea-level data processing. This study's main objective is to evaluate the North-East Atlantic, Mediterranean and connected Seas (NEAMTWS) tsunami service providers (TSPs) dissemination process of tsunami alert messages (TAMs) basin-wide and in the Eastern Mediterranean in particular and cross-checking them against observed and modelled seismological and sea-level data. Based on the critical review of the tsunami warning messages disseminated by NOA-HLNTWC and other TSPs (which is a TSP in the Eastern Mediterranean) and received by NRIAG (which is a TWFP for Egypt), a comprehensive review of the tsunami early warning system tools and procedures is urgently needed in the Eastern Mediterranean Sea. Moreover, it is crucial to show the active involvement of countries on the southern coast of the Mediterranean, since tsunami warning can only be efficient with international cooperation on data (seismic and sea level), and procedures, with the participation of all the Mediterranean shorelines.
... The existing evidence, however, excludes such possibilities, and since the description of the tsunami by Ammianus is realistic, it could only originate from an event which had affected only the part of Alexandria outside of the walls. This interpretation is consistent with palaeotsunami layers along the Egyptian coast, correlating with a tsunami in AD365 (Salameh et al. 2018). ...
This study focusses on earthquakes in the NW Africa coast during the Roman period (circa 100BC–AD500). For this period, only one earthquake is known from written sources and two from inscriptions explicitly mentioning seismic events. Hence, the corresponding apparent seismicity rate is too small compared to the rate of the instrumental period. This apparent deficit may be due (1) to an interval of seismic quiescence of the North Africa compressional front or (2) to silence of historical sources. To shed light to this problem, seen from a broader perspective, a systematic study of the Roman literature focussing on earthquakes and related effects on a regional scale has started some time ago. A first result is that since the middle of the fourth century AD earthquakes were a tool of propaganda between Christians and pagans, hence any reference to earthquakes in this period, usually vague, should be treated with much care. Methods to decode and evaluate this type of information are discussed, and in addition it is highlighted that the recent digitalization of historical sources opens new ways in earthquake studies. This study represents a tribute to Assia Harbi, whose research covered ancient earthquakes and which unfortunately remained uncomplete.
... This tsunami was probably also highly attenuated at the easternmost parts of the Mediterranean, in agreement with reports for absence of tsunami traces in Cyprus (Kelletat and Schnellman, 2002). Sedimentological traces of this tsunami are expected as far as the western coasts of Egypt (compare with Salameh et al., 2018), but no signs of tsunami in damaged coastal towns of Libya have been reported (Di Vita, 1995). ...
Earthquake and tsunami hazards along the Mediterranean coast of Africa are essentially constrained by historical data, and especially a notorious description of the AD365 tsunami by Ammianus Marcellinus, a historian of the Roman period. This report was used to constrain geophysical models, for example, the modeling of inundation of Alexandria by a tsunami generated by a fault offshore Crete. This approach, however, has some limitations. The AD365 tsunami models predict major impact in Libya (for which no clear evidence exists), limited impact in Alexandria (in which major damage is reported by Ammianus), and no retreat of the sea preceding the flooding in contrast to the ancient report. Furthermore, minor flooding is predicted for Methoni (SW Greece mainland), for which major inundation is reported. For this reason, the available historical information was examined through a comparative historical approach, and it was investigated whether the postulated tsunami damage is compatible with the political, religious, cultural, etc., history of Alexandria. The overall conclusion is that Ammianus reported a tsunami which was destructive probably in the lowlands of the Nile Delta, but not in Alexandria. Such a tsunami is unlikely to originate from Crete.
... In section M3, however, the sedimentary hiatus spans a shorter period, up to the 2nd-3rd centuries CE, meaning that an older tsunami would have eroded these lake bottoms. Three tsunamic layers deposited during the last 2000 years were found within coastal lagoons protected by 2-20 m high dunes on the northwestern coast of Egypt (Salama et al., 2018). ...
Lake Maryut (northwestern Nile Delta, Egypt) was a key feature of
Alexandria's hinterland and economy during Greco-Roman times. Its shores
accommodated major economic centers, and the lake acted as a gateway between
the Nile valley and the Mediterranean. It is suggested that lake-level
changes, connections with the Nile and the sea, and possible high-energy
events considerably shaped the human occupation history of the Maryut. To
reconstruct Lake Maryut hydrology in historical times, we used faunal
remains, geochemistry (Sr isotopic signature of ostracods) and
geoarcheological indicators of relative lake-level changes. The data show
both a rise in Nile inputs to the basin during the first millennia BCE and CE
and a lake-level rise of ca. 1.5 m during the Roman period. A high-energy
deposit, inferred from reworked radiocarbon dates, may explain an enigmatic
sedimentary hiatus previously attested to in Maryut's chronostratigraphy.
