Event 7 in trench T-6 was identified on a Holocene alluvial fan surface within the marginal fault zone of the Elat fault system in the southern Arava Valley. Trench T-6 was excavated across a north-trending fault trace belonging to the same approximately 3.5-km-long fault line investigated in trenches T-15, T-16, and T-17. The broader marginal fault zone is characterized by normal faulting arranged in a domino structure across the alluvial-fan surfaces of Wadi Roded, Wadi Shehoret, and Wadi Avrona. Amit et al. (2002) note that the displaced alluvial surfaces range in age from the Holocene to the Pleistocene and that the faults produce shallow saddles and linear scarps aligned along north-trending lineaments. Trench T-6 preserved one of the longest paleoseismic records identified within the marginal fault zone, exposing evidence for at least seven surface-rupturing events spanning the late Pleistocene and Holocene. Event 7 represents the youngest recognized event in this sequence and was identified through the development of colluvial wedge in unit 19. The event produced approximately 0.5 m of vertical displacement, indicating a moderate surface-rupturing earthquake within the Holocene alluvial sequence. Amit et al. (2002) emphasize that the number of preserved tectonic events and the amount of displacement vary substantially between nearby trenches within the same fault system due to differences in sedimentation, erosion, and local fault geometry.

Event 7 in trench T-6 was dated using a combination of pedogenic interpretation and luminescence dating. Amit et al. (2002) estimate that the event occurred at approximately 10 ± 5 ka, corresponding approximately to 8000 ± 5000 BCE, or roughly 13000-3000 BCE. Using the Wells and Coppersmith (1994) maximum-displacement relation for normal faults, a vertical displacement of 0.5 m corresponds to an estimated moment magnitude of approximately M_W 6.4.

• Fig. 2 Geomorphic Map of the
  Figure 2
  
  Map of the southern Arava Valley showing the main morphologic and morphotectonic elements of the southern Arava Valley. Notice marginal and central fault zones, the distribution of the trenches across the selected fault lines, and the location of the seismic lines. Trenches T-6, T-17, and T-16 are located along the same fault line.
  
  JW: Trench T-20 apppears to be mislocated on this map and should be further north
  
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  Amit et al. (2002)
  southern Arava showing the location of Trench T-6 from Amit et al. (2002)
• Fig. 2 Geomorphic Map of the
  Figure 2
  
  Geomorphic map of the southern Arava valley in the Avrona basin.
  
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  Zilberman et al. (2005)
  southern Arava from Zilberman et al. (2005)
• Fig. 9a Aerial photograph showing
  Figure 9a
  
  An aerial photograph of the Shehoret alluvial fan. Most of the trenches discussed in the paper are marked on this photograph. Notice the Holocene alluvial fan (Qa3) crossed by an asymmetrical, north-trending graben structure, marked by arrows.
  
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  Amit et al. (2002)
  location of Trench T-6 from Amit et al. (2002)
• Fig. 1b Location Map for
  Figure 1b
  
  Geomorphological map of the Nahal Shehoret alluvial fan showing lineaments and faults, Pleistocene and Holocene surfaces and Trench T-18 across the graben (modified from Enzel et al., 1996).
  
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  Porat et al. (2009)
  Trenches T-1, T-6, and T-18 from Porat et al. (2009)

Figure 4

Log of the southern wall of trench T-6 across one of the faults that crosses the marginal fault zone. The location of trench T-6 is shown in Figures 2 and 9A.

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Amit et al. (2002)