In the transform boundaries, also called conservative boundaries, the adjacent plates move alongside past each other. This movement is called strike-slip motion. There are many examples, which represent transform faults around the world such as: The San Andreas Fault in California, the Alpian Fault in Newzeland, the North Anatolian Fault System in Turkey and the Dead Sea Transform in the Middle East.
The Dead Sea transform fault System (DSTFS) extends from Aqaba Gulf in the south to the Taurus Mountains in the north with a length of 1100km, and a varying width of five to 30 km. It is a part of the East African-Syrian Rift System.
The Dead Sea Transform Fault System (DSTFS) is often considered as a standard case for a pull-apart basin, it is one of the tectonic features with much importance in the world, and it is linking the Red Sea spreading center with the Neo- Tethyan collision in Turkey. The northeastern corner of the Dead Seashore is the focus of this thesis. In fact, the structures and many of the structural features in the Dead Sea area have been studied in detail on both: the eastern and western areas of the Dead Sea. The retreat of the Dead Sea has exposed new lands and geologic features including geologic structures indicating the active faulting in the recent sediments and traces of movements along fault planes.
The problems of, sinkholes, land subsidence, and landslides of the shores of the Dead Sea have been studied from their pure structural, geophysical and hydro geological points of view, in addition to activities caused by humans. Previous studies comprised ancient exposed areas, where as this thesis will cover the recent exposed areas that emerged because of retreating DS during the last few decades. Moreover, this thesis includes detailed information about the effect of faults on the recent sediments and the evidence of fault activity as portrayed in the sedimentary structures linked to tectonic activities.
This study deals with recently exposed structures in the sub-recent sediments and the movements along Sweimeh-Hallabat Structure, Dead Sea Transform Fault and Shueib-Suweileh Reverse Flexure from a structural aspect with a focus on the recent sediments, which show a variety of structural features, those accompany the movements, such as flextures, faults, folds, seismites, undulations and turbulence in sediments.
1.2 The Study Area
The study focuses on the area at the NE edge of the Dead Sea (Figure 1.1) but it also deals with other areas to link the recent structures with the different ancient structural features as indicator on the activity of the ancient structures caused by recent tectonic movements.
In this study, outcrops showing the activity of faults in Sweimeh and other areas along the northeastern side of the Dead Sea and the distinct evidence pieces that hint on the continuous movements in the recent sediments and along older structures will be investigated. The thesis will try to investigate by field mapping the recently exposed features, which have affected the NE, edge of the Dead Sea, document them and correlate them with the three major structures of Sweimeh-Hallabat striking ENE- WSW and Shueib-Suweilih system striking NNE-SSW and the Dead Sea Structure striking N-S. The thesis is expected to answer the following questions:
1- Is the relationship between the old flexures of Sweimeh-Hallabat and the Dead Sea structure and the recent structures present in the near-shore sediments?
2- What evidence pieces are imprinted in the recent sediments, which have been recently exposed due to the retreat of the Dead Sea that proves the activities along the Dead Sea Transform and Sweimeh-Hallabat and shueib-suweileh structures?
1.3 The Structures and Unique Features in the Study Area
In the study area three structural systems intersect:
1- The main fault system: Dead Sea Transform Fault (DSTF)
2- Shueib-Suweilih structure (SSS)
3-Sweimeh-Hallabat structure (SHS)
In this study, it will be also tried to study the relationships between these three systems. On the other hand, the study represents some special features in the study area such as seismites, flexures and sub aquatic sliding. It has been recognized that the Dead Sea faulting activity has started in the Miocene and has been accompanied by earthquakes.
It is remarkable to find of traces seismites portrayed in sediments. Sweimeh-Hallabat Structure (SHS) also called Amman- Hallabat Structure(AHS) is one of the main structures in the study area extending for about 80km in an ENE direction from the most north eastern corner of the Dead Sea passing through Wadi Kafrain to Amman and finally it disappears in Qasr Al Hallabat area below the basalt flows. Shueib- Suweilih Structure (SSS) also called Suweilih Structure (Bender, 1968; Salameh 1980) also extends for about 55km in a NNE direction, 1-4 km in width, and it contains many structural features such as: faults (thrust fault), synclines and anticlines that difference in wavelengths. This structure starts at the northeastern edge of the Dead Sea and continues toward NNE to Zarqa River where it terminates.