Event 3 in trench T-17 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-17 was excavated across a north-trending fault trace belonging to the same approximately 3.5-km-long fault line investigated in trenches T-6, T-15, and T-16. 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. Unlike trench T-15, which exposed evidence for only a single Holocene rupture, trench T-17 preserved evidence for multiple tectonic events. Event 3 represents one stage in this longer history of repeated surface deformation along the marginal fault system. The event was recognized through colluvial wedge C3 and produced approximately 0.4 m of vertical displacement, indicating moderate surface rupture within the Holocene alluvial sequence. Amit et al. (2002) emphasize that both the amount of displacement and the preservation of individual events vary considerably between adjacent trenches within the same fault zone, reflecting localized deformation patterns and differences in sediment preservation.

Event 3 in trench T-17 was dated using a combination of pedogenic interpretation and luminescence dating dating. Amit et al. (2002) estimate that the event occurred at approximately 5 ± 2 ka, corresponding approximately to 3000 ± 2000 BCE, or roughly 5000-1000 BCE. Using the Wells and Coppersmith (1994) maximum-displacement relation for normal faults, a vertical displacement of 0.4 m corresponds to an estimated moment magnitude of approximately M_W 6.3.

• 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
  
  click on image to open in a new tab
  
  Amit et al. (2002)
  southern Arava showing the location of Trench T-17 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-17 from Amit et al. (2002)

Figure 5

Log of the southern wall of trench T-17, 100 m north of trench T-6 across the same fault line. The location of trench T-17 is shown in Figures 2 and 9A.

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Amit et al. (2002)