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The geodynamic evolution of the Dead Sea Transform (DST) remains one of the most contentious issues of the eastern Mediterranean tectonics. Therefore, wide-ranging geophysical surveys have been carried out over five decades to fill the gap of geological information existing in the region. The collected data sets allowed new models to be constructed, improving the knowledge of the crustal and lithospheric structure of the DST, and the reformulation of its complex tectonic history. In this context, the contribution of gravity and magnetic investigations deserves, with no doubt, a review on both large and small scales. The potential data were employed to interpret the evolution of the Dead Sea basin, delineating the crustal and upper mantle structure and modelling the density distribution of the sediments. The crystalline basement structure and magmatic intrusions were investigated, and underground structures of salt diapirs were explained and sinkhole hazards were detected along the Dead Sea coast. In order to produce the first comprehensive compilation of gravity and magnetic studies in the Jordan DST zone, all available potential field data were combined and revised. The main features of the potential fields resulting from these surveys were described, and the qualitative and quantitative interpretations proposed by several authors were abridged. The information presented by this paper will help interested geoscientists, in different geological fields, with their regional and local studies in the Jordan DST zone region. The compilation of geophysical observations presented here may also facilitate the understanding of similar transform systems elsewhere. [ABSTRACT FROM AUTHOR]

Groundwater is the main source of fresh water for domestic and agricultural uses in Palestine. Increased dependence on groundwater demonstrates the dire need to improve aquifer management in terms of understanding and controlling recharge and discharge issues. An artificial groundwater recharge feasibility study was proposed as one of the viable options to halt the decline of groundwater storage in Wadi Abu Al-Qamrah (WAAQ) area located in Hebron, south of the West Bank. Artificial recharge provides natural storage with minimum surface area requirements. It also minimizes evaporation loss, improves water quality, and utilizes surplus surface water runoff. The geology, soil, land cover, and natural streams were mapped using GIS and spatial analysis techniques. Geologic, hydrologic, and piezometric analyses were performed to support the decision. The geological investigation shows that there are two dominant geological formations in the study area: The Cenomanian formation at the foothills east and west, and the lower Cenomanian formation down in the valley. The hydrological analysis using the SCS-CN method indicates that the annual runoff generation in the catchment is estimated at about 0.33 MCM, among which, 70% comes from the upper urbanized part. The piezometric analysis obtained from monitoring the water level in thirty-three dug wells showed that in a short period of time, three months after the end of the rainy season, water table elevation was being declined at about 8 meters. This can be attributed to excessive abstraction. Based on the results of these analyses, several artificial recharge methods were proposed to check their suitability for the study area. The injection wells method was found to be the most suitable for WAAQ. This will enhance the sustainable groundwater management in the West Bank. To achieve this objective, a design well for the injection process is proposed. The potential locations the injection wells have been suggested based on the hydrological and geological analyses. [ABSTRACT FROM AUTHOR]

Finding suitable sites for landfills is one of the most difficult tasks in solid waste management. The sanitary landfill site selection must address social, environmental and technical concerns. This work aims at assessing the geospatial implications posed by the current Zahrat Al Finjan (ZF) landfill disposal site, located in the north of the West Bank in Jenin districts. GIS-based assessment was employed for different criteria including geology, soil, slope, land use, and stream network. This paper focuses on the assessment of ZF landfill potential environmental impacts on groundwater, sensitive ecosystems, rural areas and land use. The existing soil mantle at the landfill site consisting of clay and marly clay is influenced natural attenuation of the leachate infiltration. Nevertheless, uncontrolled accumulation of the leachate and the absence of a properly treated collection system pose potential contamination risk to shallow groundwater aquifer in the future. Also, gas produced from the landfill is not vented and so leaves from the cover and poses fire risk, and as dissolved in the leachate causes unpleasant odors. Spread of flies, mosquitoes, bird droppings, rodents and spread of stray dogs are other negative impacts of the poorly operated landfill. Monitoring systems and recommendations are proposed in this paper. [ABSTRACT FROM AUTHOR]

The Dead Sea Transform (DST) in the Middle East is a fault zone of about 1000 km length, with a total of ca. 107 km of left-lateral transform motion since early Miocene (~20 My). It shows uplifted flanks and several deep pull-apart basins, most prominently the Dead Sea Basin (DSB). This study focuses on the DSB and the southern part of the DST, the Arava/Araba Valley with its dominant fault, the Arava/Araba Fault (AF), using a multi-disciplinary approach combining seismics, seismology, gravity, and modelling. Central questions addressed are: (1) What is the crustal structure of the DSB and the Arava/Araba Valley? (2) Is it possible to reconstruct the crustal structure prior to the formation of the DST? (3) What is the interplay between structure and kinematics?Main results of this study are that several faults, manifested in strong lateral velocity gradients, exist in the upper crust in a 40-km-wide zone centered on the AF. The crustal thickness under the southern part of the DST increases smoothly from west to east from 26 to 39 km, with only a small asymmetric topography of the Mohorovičić Discontinuity (Moho) beneath the DST. The massive reworking of the upper crust in the DSB is manifested in deep sedimentary basins interspersed with slivers of high velocity material, most likely associated with the boundary faults. The DSB has a sedimentary fill of more than 8 km and contains three large salt diapirs, under the northern basin, the Lisan peninsula, and Mount Sedom, respectively. In contrast to the shallow structure, the interfaces below about 20 km depth show less than 3 km variation under the DSB.By removing the ca. 107 km of strike-slip motion along the DST and the subsidence associated with the various basins along the structure, a composite section of the crustal structure 20 My ago can be constructed. At deeper level there is strong evidence that the DST formed at the point where the crust starts to thin toward the Mediterranean Sea, with perhaps a pre-existent small depression in the Moho along the western flank of the DST.Thermo-mechanical modelling corroborates most of these findings. Shear deformation in the upper crust is localized along one or two major faults. For the DSB, it is found that N-S extension is the main cause for the thinning of the upper crust, and E-W extension is only a very minor component. The Dead Sea pull-apart basin is most likely an upper crustal feature, with the boundary between the upper and lower crust at about 20 km depth most probably acting as a decoupling zone. [ABSTRACT FROM AUTHOR]