Late pleistocene to holocene wetlands now covered by sand, along the Carmel coast, Israel, and their relation to human settlement: An example from Dor

Seismic cross-sections and drillings, which were carried out as part of a larger research program in the area of Dor on the southern Carmel coast of Israel, indicate that the young stratigraphic sequence consists of sand that unconformably overlies dark clays, with the dark clay unit becoming reddish-brown paleosol at the bottom. This sequence of sands, clays and paleosol overlies the irregular topography of the late Pleistocene calcareous sandstone (locally named kurkar). The topography of the kurkar consists of continuous, undulating areas. The dark clays in the study area were deposited in marshes that filled two different depressions. The sediments contain foraminifera, ostracodes, and mollusks (bivalves and gastropods). Most of the well-preserved species indicate low to brackish water salinity. The ages obtained for the dark clay unit in the Dor area, both by using ¹⁴C and infrared stimulated luminescence (IRSL), are given in thousands of years. At the northern depression, the oldest age obtained by ¹⁴C is 17,915 ± 185 BP, while IRSL obtained a date of 21,800 ± 1,900 yr. for the same sample. At the southern depression, the oldest age of the clay obtained by ¹⁴C is 16,680 ± 1200 BP, while IRSL obtained an age of 13,800 ± 1,000 yr. in one borehole and ¹⁴C age of 12,165 ± 100 BP in the second borehole. The top of the clay unit is dated by ¹⁴C to 8,770 ± 60 BP and 8,650 ± 75 BP in the southern depression, and to 9,520 ± 130 BP in the northern one. A low sea level is indicated during the entire period. At 8500 BP, which is the youngest date for the existence of coastal marshes at Dor, the sea level was probably around -20 m, but certainly not higher than -13 to -16 m, and the coast was at about 1.5-1.0 km off the present one. Shortly after the drying up of the marshes, human sedentary started at the Carmel coast on top of the dark clay unit, beginning at the Pre-Pottery Neolithic B period (that ends at about 8000 BP), and continued through the Pottery Neolithic and the Chalcolithic periods (up to ca 5100 BP). Only during the Middle Bronze IIA period, at about 4000 BP, when sea level rose to about -1m to -2 m, people started to settled on the kurkar hills along the coast and sands started to accumulate in the area. The sea reached its present level in the last 2000 years, carrying the sands that cover the coastal clays and the early settlements mentioned, and creating the relatively smooth present-day coastline.