Elat Sabhka Trenches
| Description | Image | Source |
|---|---|---|
| Location Map |
Fig. 1(a) Regional tectonic map of the Dead Sea Transform and location of the Gulf of Aqaba/Elat (b) Topographic image map of the southern Arava Valley showing location of the study area of the Elat Sabkha. Previously mapped faults in black lines (after Garfunkel, 1970; Garfunkel et al., 1981; Sneh et al., 1998). Previous study sites including Avrona Sabkha and Yovata Sabkha and locations of the paleoseismic trenches (in block circles)
CMP shots discussed in this study from seismic lines SI-4047 and GI-2108 are plotted as light-blue dots and yellow dots, respectively. The blue rectangle marks the extent of the study area maps presented in Figs. 3 and 9. The pink line represents the location of the offshore high-resolution seismic profile by Hartman et al. (2014) detailed in Fig. 2b. Kanari et al (2020) |
Fig. 1 - from Kanari et al (2020) |
| Bathymetric Map |
Fig. 2aBathymetric map of the north end of the Gulf of Aqaba/Elat (Sade et al., 2008; Tibor et al., 2010) showing the location of faults on the shelf of the northern Gulf of Aqaba/Elat as mapped from interpretation of seismic reflection data (Hartman et al., 2014). Kanari et al (2020) |
Fig. 2a - from Kanari et al (2020) |
| Seismic Profile |
Fig. 2bcomposite marine high-resolution seismic reflection profile across the gulf showing the six faults dividing the basin into the Elat sub-basin, Ayla horst, and Aqaba sub-basin (after Hartman et al., 2014). The location of the composite profile is marked in a pink line and the coastline of the GAE marked in black. Kanari et al (2020) |
Fig. 2b - from Kanari et al (2020) |
| Faults on 1945 Aerial Photo |
Fig. 3aThe trace of the East Elat Fault and the Avrona Fault offshore (white lines) as mapped from seismic reflection data (after Hartman et al., 2014), and interpreted lineaments suspect as fault traces around the Elat Sabkha (yellow dashed lines) based on a pre-urbanization aerial photo from 1945 (Palestine Survey PS43–6003 and PS43–6017). Kanari et al (2020) |
Fig. 3a - from Kanari et al (2020) |
| Faults on Satellite Image |
Fig. 3bThe Avrona Fault offshore and the lineaments georeferenced to a modern satellite image, and the dataset used in the current study: location of seismic reflection profiles SI-4047 (light-blue circles mark CMP numbers), GI-2108 (yellow circles mark CMP numbers) and GI-2210 (blue line) and the paleoseismic trenches T1 and T3. The Hotel District of Elat is marked for reference to its vicinity to the surface rupture prone area. The seismic profiles are presented in Fig. 4. Kanari et al (2020) |
Fig. 3b - from Kanari et al (2020) |
| Seismic line GI-2108 |
Fig. 4aSeismic line GI-2108 extending E-W on the southern part of the Elat Sabkha including interpretation of the Avrona Fault strands (yellow) and the Elat Fault (green); specific CMP points at interpreted fault strands are marked in red triangles (same CMPs are marked in Fig. 9). Kanari et al (2020) |
Fig. 4a - from Kanari et al (2020) |
| Seismic line SI-4047 |
Fig. 4bSeismic line SI-4047 extending S-N on the eastern part of the Elat Sabkha including interpretation of the Avrona Fault strands (yellow) and the Elat Fault (green); specific CMP points at interpreted fault strands are marked in red triangles (same CMPs are marked in Fig. 9).
Kanari et al (2020) |
Fig. 4b - from Kanari et al (2020) |
| Seismic line GI-2210 |
Fig. 4cHigh-resolution seismic line GI-2210 extending S-N on the eastern part of the Elat Sabkha including interpretation of the Avrona Fault strands (yellow); This line overlaps line SI-4047 (panel b) while the high resolution allows to identify fault offsets and deformation reaching up close to the surface. See Fig. 3 for location of the lines. Kanari et al (2020) |
Fig. 4c - from Kanari et al (2020) |
| Trench Log T3 fault zone |
Fig. 5bTrench T3 log of the fault zone: The top 80 cm of the trench were disturbed by farming (marked by white dashed boundary). U1-U8 are stratigraphic units and F1-F11 are interpreted fault strands (see text for detail). Yellow hexagons mark charcoal samples locations; dated samples have adjacent radiocarbon age determinations presented. E1 and E2 are the interpreted event horizons which represent the faulting events (see text for detail). (b) The complete 0–7 m fault zone log; blue rectangle marks the area of panel (a); The presented log is simplified for clarity of the figure; a high-resolution more detailed log is available in the supplementary material SM1 Kanari et al (2020) |
Fig. 5b - from Kanari et al (2020) |
| Trench Log T3 fault zone (detailed blowup) |
Fig. 5aTrench T3 log of the fault zone: The top 80 cm of the trench were disturbed by farming (marked by white dashed boundary). U1-U8 are stratigraphic units and F1-F11 are interpreted fault strands (see text for detail). Yellow hexagons mark charcoal samples locations; dated samples have adjacent radiocarbon age determinations presented. E1 and E2 are the interpreted event horizons which represent the faulting events (see text for detail). (a) detailed blow-up of the 3–5 m faulted strata in the fault zone Kanari et al (2020) |
Fig. 5a - from Kanari et al (2020) |
| Trench Log T3 sand blow 1 |
Fig. 6aLiquefaction features and their spatial extent. (a) Trench log of Sand blow 1 structure (SB1) in T3 and its logged stratigraphic structure; boundaries of sand blow outlined in black dashed rectangle; L1-L7 are stratigraphic units of the West Sabkha (see text for detail). Yellow hexagons mark charcoal samples locations; dated samples have adjacent radiocarbon age determinations presented. Kanari et al (2020) |
Fig. 6a - from Kanari et al (2020) |
| Trench Log T3 sand blow 2 photomosaic |
Fig. 6bLiquefaction features and their spatial extent. (b) photo mosaic of Sand blow 2 structure (SB2) in T3; no detailed log is available for SB2 Kanari et al (2020) |
Fig. 6b - from Kanari et al (2020) |
| Trench Log T1 liquefaction fluid escape structures |
Fig. 6bLiquefaction features and their spatial extent. (c) T1 liquefaction fluid escape structures (interpreted in yellow on photo) and its charcoal ET02 sample; white arrow points out liquefaction related feature. Kanari et al (2020) |
Fig. 6c - from Kanari et al (2020) |
| liquefaction evidence from the 1995 Nuweiba M 7.2 earthquake |
Fig. 6dLiquefaction features and their spatial extent. (d) liquefaction evidence from the 1995 Nuweiba M 7.2 earthquake, still visible today in the vicinity of T1; white arrow points out liquefaction related feature; photo taken in December 2011 Kanari et al (2020) |
Fig. 6d - from Kanari et al (2020) |
| map of trenches T1 and T3 area |
Fig. 6e(e) map of trenches T1 and T3 area detailing the locations of all other features in the figure (panels a-d). For the reader's convenience, a high-resolution version of the figure is available in the supplementary material SM2 Kanari et al (2020) |
Fig. 6e - from Kanari et al (2020) |
| Sediment accumulation rate estimation for trench T3 |
Fig. 7Sediment accumulation rate estimation for trench T3: using the calibrated year BP ages of the radiocarbon ages from the bottom of the trench and the measured depth to the top of the trench, an accumulation rate was calculated. The triangles are radiocarbon ages with 2-sigma error bars and the solid lines are the linear interpolation regressions. The fault zone ages (blue) result in 0.9 mm/year accumulation rate, while the west sabkha SB1 ages (orange) result in 1.7 mm/year. Locations of charcoal samples on trench logs are presented in Figs. 5 and 6. Radiocarbon age determinations in Table 1. Kanari et al (2020) |
Fig. 7 - from Kanari et al (2020) |
| T3 Radiocarbon age model units L6 and L7 plus SB1 and SB2 |
Fig. 8aRadiocarbon age models for the deformation and liquefaction events in trench T3 using OxCal software: (a) OxCal modeled age for liquefaction event using samples from stratigraphic units L6 and L7 from SB1 and the liquefied sand from SB2 Kanari et al (2020) |
Fig. 8a - from Kanari et al (2020) |
| T3 Radiocarbon age model Events E1 and E2 |
Fig. 8aRadiocarbon age models for the deformation and liquefaction events in trench T3 using OxCal software: (b) OxCal modeled age for faulting events E1 and E2 using samples from stratigraphic units U0, U1, U4 and U5 from the fault zone. Model calculated using OxCal 4.3.2 and IntCal13 calibration curve (Bronk Ramsey, 2017; Reimer et al., 2013). Kanari et al (2020) |
Fig. 8b - from Kanari et al (2020) |
| Active fault map for Avrona Fault Zone |
Fig. 9The Avrona Fault, Avrona Fault Zone and active fault map based on the evidence for faulting presented in this study. The solid red line outlines the interpreted area with surface rupture evidence presented in this study from analysis of seismic reflection data (pink triangles) and the trench T3 fault zone (red star; location 34°58′29.86″E, 29°33′57.66”N). The area in dashed orange line is a suggested fault zone based on interpretation of our fault-potential lineaments presented in Fig. 3 (white dashed lines) and possible surface faulting deduced from the seismic reflection line GI2108 between CMPs 125–180 (pink triangles). See legend for details Kanari et al (2020) |
Fig. 9 - from Kanari et al (2020) |
| Map showing location of cores and trenches |
Figure 2Map of marine and continental data presented here: the submarine Avrona Fault mapped by Hartman (2015) in white line, paleoseismic trench locations (yellow lines), piston cores in red circles; Inset: blow-up of land survey data collections (trenches in yellow and GPR lines in black; GPR data not presented here); red star: the location of the fault observed in trench T3 (Fig. 3); red line: the suggested fault trace of the on-land Avrona Fault, traced between the edge of the submarine fault and the surface rupture of the 1068 AD and 1458 AD earthquakes observed in T3. Kanari et al (2015) |
Figure 2 - from Kanari et al (2015) |
| Grain size distribution and 14C age determinations of core P27 |
Figure 4Grain size distribution (downcore spectrum of % volume per grain diameter) and 14C age determinations (cal BC/AD) of core P27 from the northern Gulf of Aqaba Elat. 14C age calibrated using Calib 7.0 (Stuiver and Reimer, 1993) and Marine13 calibration curve (Reimer et al, 2013). Kanari et al (2015) |
Figure 4 - from Kanari et al (2015) |
| Grain size distributions of cores P17, P22, and P29 |
Figure 5Grain size distribution (downcore spectrum of % volume per grain diameter) of cores P17 (540 mbsl), P22 (316 mbsl) and P29 (282 mbsl) from the Northern Gulf of Aqaba-Elat; see Fig. 2 for core locations Kanari et al (2015) |
Figure 5 - from Kanari et al (2015) |
Fig. 9.Proposed boundary curves relating thickness of nonliquefiable surface layer to thickness of the liquefiable zone as a function of peak earthquake accelerations required to induce venting or ground rupturing at the surface. From Ishihara (1985).
Obermeier (1996)
| Sand Blow | Sand Blow Thickness (m) | Thickness of Surface Layer (m) |
|---|---|---|
| SB1 | 0.5 | ? |
| SB2 | 0.3 | ? |
| Variable | Input | Units | Notes |
|---|---|---|---|
| g | Peak Horizontal Ground Acceleration | ||
| Variable | Output (No Site Effect) |
Units | Notes |
| unitless | Conversion from PGA to Intensity using Wald et al (1999) |