International audienceThe continuous record of large surface-rupturing earthquakes along the Dead Sea fault brings unprecedented insights for paleoseismic and archaeoseismic research. In most recent studies, paleoseismic trenching documents the late Holocene faulting activity, while tectonic geomorphology addresses the long-term behavior (> 10 ka), with a tendency to smooth the effect of individual earthquake rupture events (M w > 7). Here, we combine historical, archaeological, and paleoseismic investigations to build a consolidated catalog of destructive surface-rupturing earthquakes for the last 14 ka along the left-lateral Jordan Valley fault segment. The 120-km-long fault segment limited to the north and the south by major pull-apart basins (the Hula and the Dead Sea, respectively) is mapped in detail and shows five subseg-ments with narrow stepovers (width < 3 km). We conducted quantitative geomor-phology along the fault, measured more than 20 offset drainages, excavated four trenches at two sites, and investigated archaeological sites with seismic damage in the Jordan Valley. Our results in paleoseismic trenching with 28 radiocarbon datings and the archaeoseismology at Tell Saydiyeh, supplemented with a rich historical seismic record, document 12 surface-rupturing events along the fault segment with a mean interval of ∼1160 yr and an average 5 mm=yr slip rate for the last 25 ka. The most complete part of the catalog indicates recurrence intervals that vary from 280 yr to 1500 yr, with a median value of 790 yr, and suggests an episodic behavior for the Jordan Valley fault. Our study allows a better constraint of the seismic cycle and related short-term variations (late Holocene) versus long-term behavior (Holocene and late Pleistocene) of a major continental transform fault

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.

Subsurface formations with low compaction, often, due to the presence of underlying cavities, are potential sources of hazards. Thus, understanding the occurrence, properties, and extension of these weak zones poses a major concern in engineering geophysics. In this study, we examine the ability of geophysical methods to map weak areas over carbonates in Northern Oman. The weak zones are known to cause surface depression in many areas. The geophysical methods examined involve Ground-Penetrating Radar (GPR), Seismic Refraction Tomography (SRT), and Electrical Resistivity Tomography (ERT). This integrated geophysical survey was conducted near the Bimmah sinkhole, in the Quriya area, Northern Oman. The survey covers both an area with ground truth (low compaction sediments overlaying a cave) and a part with unknown subsurface properties. GPR velocity analysis using selected diffraction’s fitting helped to identify high-velocity anomalies that were attributed to the cavity. The GPR interpretation was calibrated with SRT and ERT. The former showed a clear drop in P-wave velocity and low ray coverage at the cavity zone, while the latter demonstrated high resistivity anomalies caused by the air filling the cavity. The scope was to examine the geophysical methods response, especially the GPR, and utilize the results of this preliminary approach for a wider exploration investigation in the area. The results from the study indicated that the GPR is capable to serve as a pioneer method in detecting the cavities. Hence, the GPR will cover large area in the site and the other two methods will be used as complementary for the final subsurface conditions’ evaluation.