Turbidites in numerous R/V Thuwal Cores - ~1500-~1600 CE (1σ) Open site page in a new tab



Bektaş et al. (2024:12) report that "numerous coeval turbidites" were identified in R/V Thuwal cores. Based on Probability Density Functions (PDFs) presented in Fig. 8 of their paper, these deposits were likely emplaced between ~1500 and ~1600 CE ( ), and were interpreted as most probably associated with the CE 1588 earthquake. A sedimentary event was identified from around this time in 15 or 16 of 18 R/V Thuwal Cores, of which 12 or 13 were Type I (Turbidite Event) and 3 were Type II (Turbidite or Flooding Event). The three Type II events were identified in Core 2 in the Tiran Deep and cores 9 and 10 in the Dakar Deep. No turbidites from around this time were identified in Core 6, which was "collected from a small and isolated basin" that was "isolated from turbidity flows that would come from the main slopes of the gulf" and, due to its "relatively smaller slopes, may not be sensitive to earthquake shaking as much as the larger main slopes of the gulf." A missing turbidite from core 14 was "more difficult to explain." Bektaş et al. (2024:12) suggested two possibilities for its absence
  1. " sediment clearance on the slopes and the banks of the submarine channels during the preceding earthquake, i.e., in CE 1068, leaving nothing to be wasted during the CE 1588 earthquake."
  2. "turbidity flows due to 1588 earthquake might have bypassed the location of core 14 (Goldfinger et al., 2017)"
Bektaş et al. (2024:12-13) noted that the causative earthquake "triggered seismo-turbidites along the entire gulf" and suggested that, when one adds paleoseismic observations by Kanari et al. (2020) from the Elat Sabkha Trenches, "the CE 1588 earthquake likely [] ruptured the entire fault system in the Gulf of Aqaba"1. They added that the earthquake or earthquake and aftershock "does not seem to have propagated inland beyond the northern end of the gulf" and ruptured "south of the Tiran Strait." They surmised that the causative earthquake did not propagate inland due to an absence of a seismic event from around this time in the Qatar Trench.
Footnotes

1 Kanari et al. (2020) suggested that the 1458 CE earthquake or the 1588 CE earthquake was responsible for Event E2 in Trench T3 from the Elat Sabkha Trenches and that the 1458 CE earthquake may have been responsible for liquefaction sand blows SB1 and SB2 in Trench T3.




Figure 4 - Sedimentary events detected in the radiographic images of the Gulf of Aqaba cores, labelled by letters and indicated by red, gray, and yellow vertical bars. Depths of 210Pb and 14C measurements are also shown by green and blue rectangles next to the images, respectively. In the table, raw and calibrated 14C results are listed. The raw and composite depths, and the depths corresponding on core 11 (after stratigraphical correlation) for each 14C sample are also given. In the lower right, results of 210Pbex measurements on cores 3, 7, and 17 and the corresponding sedimentation rates (SR) are presented. - click on image to open in a new tab - from Bektaş et al. (2024)




By Jefferson Williams