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This paper presents new findings that contribute to the understanding of the deformational style of the Wadi Shueib Structure (WSS) and the Amman-Halabat Structure (AHS) and their relationship with the regional tectonic regime of the Dead Sea Transform Fault (DSTF). Our research utilized Landsat-8 OLI imagery for the automatic extraction of lineaments, and our lineament mapping was facilitated by processing and digital image enhancement using principal component analysis (PCA). Our data revealed a relatively higher density of lineaments along the extension of the major faults of the WSS and AHS. However, a relatively lower density of lineaments was shown in areas covered by recent deposits. Two major lineament trends were observed (NNE-SSW and NW-SE) in addition to a minor one (NE-SW), and most of these lineaments are parallel to the orientation of the WSS and AHS. We offer the supposition that the DSTF has merged into the major faults of the WSS and AHS. We further suppose that these faults were reactivated as a restraining bend composed of active strike-slip fault branches that developed due to the NNW-SSE-trending Dead Sea transpressional stress field. Depending on the relationship between the direction of the WSF and AHF strands and the regional tectonic displacement along the DSTF, thrust components are present on faults with horsetail geometry, and these movements are accompanied by folding and uplifting. Thus, the major faults of the WSS and AHS represent a contractional horsetail geometry with associated folding and thrusting deformation.

The study area lies east of the northern segment of the Dead Sea Transform (DST), within the Jordan valley active strike-slip fault system. The exposed rocks in the study area consist of Upper Cretaceous to Cenozoic carbonates and cherts. This study concentrated on detailed field measurements of the various structural elements such as extensional fractures, normal faults, and strike-slip faults, with a total of 1,976 measurements. The predominant trends of all fractures (faults and joints) in the study area are N-S, NNW-SSE, and NW-SE with steep dips and characterized by sinistral and extensional modes of deformation. The NNW to NW trend has the same general trend of the water flow path in the study area. Normal and strike-slip conjugate and hybrid fracture sets with different acute dihedral angles and steep dips were observed in the study area. These fractures connect with the vertical extensional fractures in the same stratigraphic level. In addition, the interconnected orthogonal fracture systems with bedding parallel fractures play a major role conducting fluid movement and therefore, in initiation of karst development in the study area. These fractures network were enlarged by water dissolution forming small caverns.