Lefevre et al. (2018) In the Taybeh Trench, excavated across the Arava Fault, Lefevre et al. (2018) identify Event E11 as the oldest and most weakly expressed rupture in the trench sequence. This event occurs within layer B1, a coarse conglomerate, where deformation is expressed not by clear offset surfaces but by a set of cracks in the western part of the trench that are emphasized by vertically oriented and rotated pebbles. These features mark the passage of a surface-rupturing event, even though the coarse grain size and limited internal structure of the deposit obscure finer details of displacement.

Unlike younger events in the Taybeh sequence, E11 does not exhibit measurable vertical displacement. This absence is largely due to the presence of an overlying erosional surface, which truncates the upper terminations of the cracks. As a result, the original displacement associated with E11 cannot be directly observed, and the preserved deformation likely represents only the lower portion of the rupture zone. The cracks themselves, however, are well defined and consistent with brittle failure.

The structural expression of E11 is therefore limited but still diagnostic. The rotated pebbles aligned along fracture planes indicate localized shear and dilation during rupture, while the absence of continuous offset layers reflects both the coarse depositional environment and subsequent reworking. In this context, deformation is recorded primarily through fabric reorganization rather than through discrete displacement of stratigraphy. This makes E11 fundamentally different from younger events such as E3 or E2, where laminated sandy units allow precise identification of offsets and event horizons.

From a depositional perspective, the occurrence of E11 within coarse alluvial material suggests that the earthquake affected an environment dominated by high-energy sedimentation, likely associated with an active alluvial fan. Such environments tend to obscure subtle paleoseismic signatures, and the preservation of fractures within the conglomerate indicates that E11 was sufficiently energetic to disrupt even coarse, poorly stratified material. However, the subsequent erosion and redeposition associated with channel processes removed the upper part of the deformation, limiting the observable record.

Chronologically, E11 is poorly constrained. Based on radiocarbon dating of overlying and adjacent units, Lefevre et al. (2018) place this event broadly between approximately 6.1 ka BC and 5.4 ka BC. This wide interval reflects both the scarcity of datable material in the lower units and the presence of erosional contacts that introduce uncertainty into the stratigraphic sequence. The lack of historical records for this period precludes correlation with documented earthquakes, and E11 remains part of the prehistoric seismic record of the Wadi Araba.

In the broader paleoseismic context, E11 belongs to a group of early events (E11–E9) that are recorded in coarse units and are therefore less clearly expressed than younger earthquakes.

Figure 1 - (a) Detailed log of the southern wall of the trench. Units are differentiated according to facies. White dots indicate locations of ¹⁴C samples collected from both walls (the samples collected from the northern wall are represented at a stratigraphically and structurally equivalent location on the southern wall log). - Click on image to open in a new tab - LeFevre et al (2018)