Description | Image | Source |
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Location Map |
![]() ![]() (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 |
![]() ![]() Bathymetric 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 |
![]() ![]() composite 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 |
![]() ![]() The 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 |
![]() ![]() The 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 |
![]() ![]() Seismic 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 |
![]() ![]() Seismic 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 |
![]() ![]() High-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 |
![]() ![]() Trench 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) |
![]() ![]() Trench 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 |
![]() ![]() Liquefaction 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 |
![]() ![]() Liquefaction 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 |
![]() ![]() Liquefaction 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 |
![]() ![]() Liquefaction 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 |
![]() ![]() (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 |
![]() ![]() Sediment 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 |
![]() ![]() Radiocarbon 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 |
![]() ![]() Radiocarbon 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 |
![]() ![]() The 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 |
![]() ![]() Map 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 |
![]() ![]() Grain 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 |
![]() ![]() Grain 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) |
Source - Wells and Coppersmith (1994)
Variable | Input | Units | Notes |
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cm. | |||
cm. | |||
m/s | Enter a value of 655 for no site effect Equation comes from Darvasi and Agnon (2019) |
||
Variable | Output - not considering a Site Effect | Units | Notes |
unitless | Moment Magnitude for Avg. Displacement | ||
unitless | Moment Magnitude for Max. Displacement | ||
Variable | Output - Site Effect Removal | Units | Notes |
unitless | Reduce Intensity Estimate by this amount to get a pre-amplification value of Intensity |
The value given for Intensity with site effect removed is how much you should subtract from your Intensity estimate to obtain a pre-amplification value for Intensity. For example if the output is 0.5 and you estimated an Intensity of 8, your pre-amplification Intensity is now 7.5. An Intensity estimate with the site effect removed is helpful in producing an Intensity Map that will do a better job of "triangulating" the epicentral area. If you enter a VS30 greater than 655 m/s you will get a positive number, indicating that the site amplifies seismic energy. If you enter a VS30 less than 655 m/s you will get a negative number, indicating that the site attenuates seismic energy rather than amplifying it. Intensity Reduction (Ireduction) is calculated based on Equation 6 from Darvasi and Agnon (2019).
VS30 is the average seismic shear-wave velocity from the surface to a depth of 30 meters at earthquake frequencies (below ~5 Hz.). Darvasi and Agnon (2019) estimated VS30 for a number of sites in Israel. If you get VS30 from a well log, you will need to correct for intrinsic dispersion. There is a seperate geometric dispersion correction usually applied when processing the waveforms however geometric dispersion corrections are typically applied to a borehole Flexural mode generated from a Dipole source and for Dipole sources propagating in the first 30 meters of soft sediments, modal composition is typically dominated by the Stoneley wave. Shear from Stoneley estimates are approximate at best. This is a subject not well understood and widely ignored by the Geotechnical community and/or Civil Engineers but understood by a few specialists in borehole acoustics. Other considerations will apply if you get VS30 value from a cross well survey or a shallow seismic survey where the primary consideration is converting shear slowness from survey frequency to Earthquake frequency. There are also ways to estimate shear slowness from SPT & CPT tests.
Sand Blow | Sand Blow Thickness (m) | Thickness of Surface Layer (m) |
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SB1 | 0.5 | ? |
SB2 | 0.3 | ? |
Variable | Input | Units | Notes |
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g | Peak Horizontal Ground Acceleration | ||
Variable | Output (No Site Effect) |
Units | Notes |
unitless | Conversion from PGA to Intensity using Wald et al (1999) |
Abueladas, A.-R., et al. (2020). "Liquefaction Susceptibility Maps for the Aqaba-Elat Region with Projections of Future Hazards with Sea Level Rise."
Quarterly Journal of Engineering Geology and Hydrogeology 54: qjegh2020-2039.
Ash-Mor, A., et al. (2017). "Micropaleontological and taphonomic characteristics of mass transport deposits in the northern Gulf of Eilat/Aqaba, Red Sea." Marine Geology 391.
Kanari, M., et al. (2015). "On-land and offshore evidence for Holocene earthquakes in the Northern Gulf of
Aqaba-Elat, Israel/Jordan." Miscellanea INGV 27: 240-243
Kanari, M., et al. (2020). "Seismic potential of the Dead Sea Fault in the northern Gulf of Aqaba-Elat:
New evidence from liquefaction, seismic reflection, and paleoseismic data." Tectonophysics 793: 228596.
High resolution mapping of earthquake risks (Elat region) - Geological survey of Israel webpage