The Geological Evolution of the Quaternary in the Central-Northern Jordan Graben, Israel

Abstract
During the Quaternary the Jordan rift valley, 10 km wide, constituted a main accumulative basin for river deposits and lavas derived from the adjacent uplifted mountains of East Galilee and Hauran-Golan. The Quaternary clastic and volcanic fills interfingered with sediments of graben lakes in at least three major cycles. The thickness of the Quaternary fluvial-limnic-volcanic fill attains many hundred meters. Still unknown is the Lower Villafranchian stage that followed the Proto-Pleistocene breakdown of the graben. It is safe to assume that gravels were washed into the graben and formed basal conglomerates; then an initial lake formed in which the fluviatile and limnic sediments of the Middle and Upper Villafranchian (including Abbevillian) Ubeidiya formation were deposited. These cycles occur again in the Middle Pleistocene as Naharayim formation and Lower Lacustrine beds of the Hula formation, as well as in the Upper Pleistocene Lisan formation. Unconformities and disconformities resulting from graben movements enable us to discern better the different Quaternary subdivisions. A clear stratigraphic distinction was also provided by the youngest lavas of the Middle Pleistocene Yarmuk, Korazim, and Hasbani basalt where overlain by Upper Pleistocene sediments. Thus it is to the tectonic catastrophes that one may attribute the disappearance, if not the total extinction, of the Villafranchian land mammals such as Archidiskon, Hipparion, Machairodus, Leptobos, etc., or their migration to Africa, via the Suez isthmus, such as was the case with Giraffa and Rhinoceros. The most decisive crisis during or after the inter-Pleistocene “revolution” occurred among the Hominidae. Sinanthropus or Pithecanthropus of the Villafranchian Ubeidiya formation is replaced in the Middle-Upper Pleistocene by Neanderthaloid and finally by the Homo sapiens types discovered in many caves in Galilee and in the Carmel. It was principally Paleolithic man who populated the caves. Men of the Villafranchian pebble culture, however, lived in the open air, as did (after the Palaeolithic) the first agricultural settlers of the Natufian-Neolithic.