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Recent surface and subsurface geological investigations in Israel and Jordan provide new data for the re-examination of Dubertret’s (1932) hypothesis of the left-hand shear along the Dead Sea rift. It is found that while none of the pre-Tertiary sedimentary or igneous rock units extend right across the rift, all of them resume a reasonable palaeographical configuration once the east side of the rift is placed 105 km south of its present position. It is therefore concluded that the 105 km post-Cretaceous, left-hand shear along the Dead Sea rift is well established. The 40 to 45 km offset of Miocene rocks and smaller offsets of younger features indicate an average shear movement rate of 0.4 to 0.6 cm a -1 during the last 7 to 10 Ma. Unfortunately, the 60 km pre-Miocene movement cannot be dated yet. Along the Arava and Gulf of Aqaba and in Lebanon the shear is divided over a wide fault zone within and outside the rift.

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Mount Sedom is a salt diapir, on the southwestern shore of the Dead Sea, which has been rising above the local base level throughout the Holocene. Karst development within the salt body has kept pace with the rise forming subhorizontal cave passages with vertical shafts. Wood fragments found embedded in flood sediments that were deposited in the cave passages yielded 14C ages ranging from c. 7100 to 200 BP. A palaeoclimatic sequence was constructed, based on parameters that include: relative abundance of plant types or floral communities, the elevations of the corresponding cave passages and the ratio of their width to present passage width. The results were correlated to the Holocene sedimentary sequence of the Dead Sea Basin, and other features associated with shifting lake levels. Moister climatic stages are indicated by relatively abundant wood remains, by wide cave passages and by elevated outlets indicating high Dead Sea level. Arid periods are marked by a scarcity of wood remains, by narrow cave passages and by low-level outlets. The Holocene sequence of Mount Sedom is subdivided into 10 climatic stages: A moist stage in the early Holocene, older than 7000 BP, and nine subsequent stages of drier climate, fluctuating between conditions that are somewhat drier, up to somewhat moister than those of today. The Dead Sea level dropped from c. -300 MSL during the early moist period to -400 MSL or lower during the subsequent arid periods.