Landscape Evolution of the Central Negev

This chapter presents the main features composing the Central Negev landscape and discusses their origin and evolution. The present landscape contains a mosaic of morphotectonic elements developed during the last 90 Ma through several geologic events. The Syrian Arc fold structures, expressed by the Ramon and Arif-Badad monoclines and their adjacent synclines, Avedat and Loz-Neqarot, developed at 90–50 Ma and still dominate the present-day landscape. The regional truncation surface (RTS) that originated during the Oligocene and Early Miocene (30–20 Ma) controls the contemporary skyline, while large fault lines, tectonic depressions and dome structures that locally deformed the general flat relief testify to the Early Miocene to Early Pleistocene (18–1.5 Ma) tectonic activity. This activity terminated the evolution of the Sinai-Israel microplate and generated the development of the cliff systems and the deeply incised canyons and valleys. Although the present-day landscape is under ongoing development, in most cases, it is possible to link the young geomorphic features to older structures that were rejuvenated. This pattern is best demonstrated by the deeply incised valleys developed within the core of the Syrian Arc anticlines (Makhteshim). Although their development was initiated in the Late Cretaceous, their near-present dimensions were controlled by the Oligocene truncation event, while their development towards the oval-incised valleys was caused by younger tectonic events occurring during the Miocene. Most of the time, the landscape evolutionary processes were active under arid climates, contributing to good preservation of morphotectonic and geomorphologic features. These environmental conditions promoted the human occupation of this desert region, located at the crossroad between Africa and Asia, over the past 1.5 Ma.