General bathymetry of the eastern Mediterranean Sea showing the proximity of the 500-m isobaths at various locations along the shore. Note the occurrence of shallower waters offshore the Nile Delta and the wider shelf area along the eastern shore of Egypt (Sinai Desert), where the impacts of tsunami wave run-up could be significantly enhanced. ETOPO2 represents gridded (2 3 2 min) elevation and bathymetry for the world. (Data derived from the National Geophysical Data Center’s ETOPO2 Global 2 9 Elevations data set from September 2001). 

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... with 200 tsunamis being recorded over the last five centuries. Over the last four centuries, there have been 15 tsunamis every century around Italy. In 1628 BC, the coasts of the entire eastern Mediterranean were submerged by 60-m-high waves caused by a volcanic eruption on Santorini, a Greek island in the Aegean Sea. Earthquake-induced tsunamis originating near the Greek islands of Rhodes and Crete in AD 365 and 303 destroyed coastal developments as far away as Egypt’s Nile Delta, the earlier tsunami killing thousands of people in the city of Alexandria (Galanopoulos, 1960; Pararas-Carayannis, 1992). Geological research and historical records report that many powerful tsunamis have taken the lives of thousands of people over the ages in this region. Because the area is clearly tsunami prone, the Suez Canal and its associated infrastructure are likely vulnerable to long-wave impacts in the future. Opened to shipping in 1869, its maximum navigational depth was then 8 m. Port Said was constructed by 1871, formed by two breakwaters that extended seaward from the low sandy coast. By 1890, the depth had been increased to 8.5 m. The first coal-fueled ship transited the Suez Canal in 1908, and diesel-powered ships were moving through the waterway by 1912. In 2011, cargo ships bigger than 10,000 gross tons made up about 93% of the world’s total capacity. Over time, the increasing length and draft of large vessels promoted a gradual improvement in navigational conditions by enlargement of curves ( i.e., lessening of curvatures) and standardization of the waterway’s navigable depth. Although there were narrower channel widths in the past, today the canal averages about 300 m wide with an effective navigation width of about 225 m at an 11-m water depth. The present cross-sectional configuration of the canal is shown in Figure 2. A common perception of change in eustatic sea level is that it will rise, flooding low-lying coastal areas ( e.g., Church et al., 2001; IPCC, 2001). Global sea-level rise will eventually affect the canal, requiring the imposition of sea locks to avoid flooding. While the depressed relief of the Suez Canal corridor is considered to be a part of the ancient Nile River’s delta, the delta in its destructive phase (eroding) is now subsiding and tilting to the NE toward the entrance/exit at Ports Said and Fouad (Coutellier and Stanley, 1987; Frihy, 2003; Stanley, 1990; Stanley and Warne, 1998; Stanley, McRea, and Waldron, 1996). In addition to subsidence and erosion of the delta, a second noteworthy macroproblem is the possibility of seismic jolts along the Suez–Cairo–Alexandria shear fault zone (Elenean, Mohamed, and Hussein, 2010). Well-documented 21st-century earthquakes took place there on 29 June 2000, 7 July 2005, and 30 October 2007. Faults, shear zones, and lineament swarms making up part of the tectonic pattern in NE Egypt contribute to seismic risks that could adversely affect the integrity of the canal per se ( e.g., El-Sayed, Korrat, and Hussein, 2004; Neev, 1977; Neev and Friedman, 1978; Neev, Hall, and Saul, 1982). Earthquakes in the eastern Mediterranean Sea in the recorded past caused tsunami run-ups on Egypt’s coastline ( e.g., Ambraseys, 1962, 2001; Eckert et al., 2011; Sintubin, 2011), so there is no hesitancy to assume more temblors as a cause of tsunamis hitting the training jetties and navigational channel of the approaches to the Suez Canal at Port Said–Port Fouad. At the other end of the Suez Canal, on the Red Sea (Figure 1A), paleotsunami deposits have been studied by Salem (2009), who found large carbonate blocks in the carbonate rock sequence alongshore. He reported that beaches on the Red Sea were subjected to paleotsunami waves due to seismic activity inside the Red Sea Basin (Gulf of Suez). His observation of paleoliquefaction and landslides was interpreted as proof that the region has been subjected to strong earthquakes related to rifting. Evidence of volcanic activity at the southern end of the Red Sea is found in Perim Island (an eroded fragment of the SW flank of a volcano from the late Miocene, 10.5 6 1.0 million years ago) and younger Holocene islands such as Jebel at Tair and the Zubair islands ( e.g., Wiart and Oppenheimer, 1999). Jebel at Tair is the northernmost known Holocene volcano in the Red Sea, with explosive eruptions reported in the 18th and 19th centuries. With historical explosive activity reported from the Zubair islands in the 19th century, it is possible that volcanism and associated earthquakes pose a tsunami threat in this region. Thus, during 19–23 December 2011, a new lava-formed island was observed near the Zubair archipelago, possibly indicating volcanic activity is increasing in the basin of the Red Sea. The main procedures used to consider potential impacts of tsunamis on the Suez Canal focus on geological, historical, archeoseismological, and anecdotal data. The general bathy- metric map of the eastern Mediterranean Sea shown in Figure 3 highlights the comparatively shallow waters on the continental shelf in the vicinity of the subsiding Nile Delta ( e.g., Syvitski et al., 2009). Here, water depths are shallow over the offshore prodelta and to the east offshore from the entrances of the Suez Canal, in the vicinity of Ports Said and Fouad. The concave seaward configuration of the coastline in plan view on the eastern flanks of the Nile Delta and its shallow water depths contribute to wave diffraction and refraction, leading to increased heights of earthquake-induced long waves. The bathymetry also shows unobstructed deep-water approaches to the Port Said–Port Fouad infrastructure. Perusal of Figure 4 shows that earthquakes (Figure 4A) and volcanic eruptions (Figure 4B) may occur almost anywhere throughout the study area, although there are definite concentrations in the region from the Greek islands (Hellenic Arc) to coastal western and southern Turkey to Crete and along the easternmost shores of the Mediterranean Sea. Earthquakes also occur in and around the Red Sea, while volcanic eruptions are recorded along the eastern margin of the Red Sea in western Saudi Arabia and southern Syria. According to Soloviev (1990), earthquakes are expected to cause 75% of the tsunami events in the Mediterranean Sea. Although there is the possibility of tsunami impacts originating in the Red Sea, this discussion focuses mostly on the Mediterranean Sea because there is much more data available in the form of tsunami catalogues, historical–archeological records, and drill core logs. Due to active lithospheric tectonic plate convergence, the Mediterranean Sea region is geodynamically characterized by high seismicity and significant volcanism ( e.g., Papadopoulos and Fokaefs, 2005). Tsunamigenesis in the Mediterranean Sea Basin is related to complex tectonics that is generally described within the purview of the collision between the Eurasian and the African tectonic plates, as summarized by Tinti et al. (2005) for different expressions in various parts of the Mediterranean Sea. The major fault and shear zones around the eastern Mediterranean Sea Basin include the Hellenic Arc, North Anatolian Fault Zone, East Anatolian Fault Zone, Cyprus Arc, Pelusium (megashear) Line, and Dead Sea Fault ( e.g., Neev, 1977; Neev, Hall, and Saul, 1982; Yal ̧iner et al., 2007; Zaytsev et al., 2008). Figure 5 is an example of some major tectonic elements in the general Suez region. Based on extractions from Neev’s (1975) maps, Figure 5 shows the Pelusium Line crossing the canal and other major faults in the area that could be sources of earthquake activity. Along the Dead Sea transform (DST) tectonic plate boundary, Girdler (1990), as discussed in Butler and Spencer (1999), points out that present-day seismicity is strongly focused on the Roum Fault, which bypasses the much larger Yammouneh Fault that has been largely inactive over the last 5 million years and which lies closer to the coast than the main transform boundary. A series of volcanic systems occurs at the center of the Aegean Sea that nearly parallels the trench and thus forms an internal arc (Milos, Antimilos, Antiparos, Santorini, Christiana, Colombus, Kos, Yali, Nisiros, etc. ). Any of these ruptures or volcanic systems constitutes a potential source of tsunamigenesis. Because seismicity in the Mediterranean Basin is strongly connected to tectonic features and because tsunamis are mostly generated by earthquakes, the geographical distribution of historical tsunamis in the region generally resembles the trend of seismicity. Due to tectonic activity in the eastern Mediterranean Basin, there is a substantial geohazard in this ...