Geological evidence of tsunamis and earthquakes at the Eastern Hellenic Arc: correlation with historical seismicity in the eastern Mediterranean Sea

Abstract

Sedimentary stratigraphy determined by trenching in Dalaman, south-western Turkey, revealed three sand layers at a distance of approximately 240 m from the shoreline and at elevations of +0.30, +0.55 and +0.90 cm. Storm surge action does not explain the features of these deposits that show instead typical characteristics of tsunami deposition. The sand layers correlate with historical tsunamis generated by large earthquakes which ruptured the eastern Hellenic Arc and Trench in 1303, 1481 and 1741. Accelerator mass spectrometry <sup>14</sup>C dating of a wood sample from layer II indicated deposition in AD 1473±46, which fits the 1481 event. From an estimated average alluvium deposition rate of approximately 0.13 cm/year, layers I and III were dated at 1322 and 1724, which may represent the large 1303 and 1741 tsunamis. The geological record of the 1303 key event is very poor; therefore, sand layer I perhaps represents an important geological signature of the 1303 tsunami. However, the strong tsunami reported to have been generated by the 1609 earthquake is missing from Dalaman stratigraphy: this underlines the sensitivity of tsunami geological signatures to various local factors. The 1303 earthquake ruptured the trench between the islands of Crete and Rhodes. For the earthquakes of 1481, 1609 and 1741 we suggested that they were very likely generated in the Rhodes Abyssal Plain where sea depths of up to approximately 4200 m, together with the thrust component of seismotectonics, favor tsunami generation. Sand dykes directed upwards from layer I to layer II indicated that the 1481 earthquake triggered liquefaction of sand layer I. The results substantially widen our knowledge about the historical earthquake and tsunami activity in the eastern Mediterranean basin.

Ege Denizi’nde Son 1500 Yılda Meydana Gelmiş Tsunamilerin Karine Lagünü’ndeki Sedimanter İzleri

“…9c). Although sedimentary traces of this tsunami were detected by Alpar et al (2012) and Papadopoulos et al (2012) in the sequence of Dalaman Plain ("Da" in Fig. 2a), and by Avşar (2019) in Ölüdeniz Lagoon, it was not detected by other studies carried out in the Aegean Sea (Di, Li, Th, DG, Go and Re in Fig.…”

Paleotsunami deposits along the coast of Egypt correlate with historical earthquake records of eastern Mediterranean

“…On 8 August AD 1303 a major earthquake with magnitude ∼ M w 8 located between Crete and Rhodes islands ( Fig. 1) generated a tsunami that greatly damaged the coastal cities of the eastern Mediterranean (Ambraseys, 2009;Papadopoulos et al, 2014). In 1329 Abu-El Fida (1907) reported that the Alexandria city and the Nile Delta were flooded and many houses were damaged in Cairo and northern Egypt.…”

“…Minoura et al (2000) described tsunami deposits with volcanic ashes along the coast on Crete (Greece) that correlate with the Thera (Santorini) eruption in the late Minoan period (1600-1300 BC). Papadopoulos et al (2012) documented three paleotsunami layers attributed to the AD 1303, AD 1481 and AD 1741 historically documented tsunamis in Dalaman (southwestern Turkey). Using granulometry, XRD, XRF, and FT-IR, Tyuleneva et al (2018) identified two sedimentary events offshore of Casearea (Israel) that may correlate with landslide tsunamis in AD 749 and 5700 BP (Chalcolithic cultural period).…”

“…Boxes indicate the paleoseismic sites of Kefr Saber and El Alamein east of the Nile delta. The major historical earthquakes (star) of AD 365 (M w 8-8.5), AD 1303 (M w ∼ 8) and AD 1870 (M w >7-7.5) are located along the Hellenic subduction zone according to Guidoboni et al (1994), Stiros (2001), Ambraseys (2009), Papadopoulos et al (2014) and Jusseret and Sintubin (2017). Focal mechanisms are from CMT-Harvard (referenced as CMT catalogue).…”

“…al., 2004). Major historical tsunamis in the eastern Mediterranean region which affected northern Egypt are triggered by large earthquakes (Papadopoulos et al, 2014). However, there is a possibility of landslide triggered tsunamis associated with local earthquakes (El-Sayed et al, 2004;Tinti et al, 2005).…”