In the Taybeh Trench, excavated across the Arava Fault, Lefevre et al. (2018) identify Event E4 as a poorly expressed rupture within the upper laminated sandy sequence, preserved around layer J. The event is defined by a series of cracks that cut through this fine yellow sandy unit, although their exact upper termination remains uncertain. Unlike E5, which is associated with a localized but identifiable vertical displacement, E4 is characterized by ambiguous structural evidence. The cracks observed within layer J may terminate at its upper boundary, but this cannot be confirmed because the overlying unit consists of a thin, discontinuous gravel layer in which deformation is difficult to recognize. As a result, it is unclear whether the fractures extend beyond layer J or are confined to it.

The structural expression of E4 is therefore weak and equivocal. While the presence of cracks indicates brittle deformation consistent with surface rupture, the absence of clearly defined offset layers or consistent fracture terminations reduces confidence in the precise definition of the event horizon. As in other fault-perpendicular trench exposures, lateral motion is not directly observable, and the recorded deformation reflects only the vertical component of a dominantly strike-slip system. From a tectonic perspective, E4 represents a phase of activity that is difficult to resolve within the stratigraphic record. The limited expression of deformation may indicate a moderate-magnitude event or one whose surface effects were only partially preserved. Alternatively, the apparent weakness of the signal may result from the coarse and discontinuous nature of the overlying sediments, which obscure or remove evidence of displacement. From a depositional standpoint, E4 occurs at a stratigraphic level where fine laminated sands are overlain by discontinuous gravel layers. This transition complicates the preservation of paleoseismic features, as deformation within the fine unit may not be transmitted clearly into the coarser overlying deposits. The resulting stratigraphic ambiguity makes it difficult to distinguish whether observed cracks represent a distinct event or are related to deformation associated with adjacent ruptures.

Chronologically, E4 is fairly well-constrained. Based on Bayesian modeling of radiocarbon dating of detrital charcoal samples from surrounding units, Lefevre et al. (2018) place the event between approximately 80 and 142 CE ( 2σ) which makes the early 2nd century CE Incense Road Earthquake a plausible candidate.

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)