A study of the luminescence properties of one of several pit features removed from the Ashkelon Marina EB1 (Early Bronze I) archaeological site during a 1998 excavation unequivocally determines their function in antiquity. The features are shallow (Ł 50 cm) cup-shaped pits preserved in the ground. A hardened and reddened layer of earth Ł 3cm thick forms the shape of each pit, and a thin layer of white calcite is observed to lie upon the hardened earth. The pit is filled with soft buff coloured, quartz-dominated sediments, indistinguishable from the sediments which underlie it. This feature, and several others at the site, are suspected to be putative fire pit installations, over which crucibles for the melting of copper had been placed. However, the lack of any direct association of copper residues or artifacts found at the site with any of the pit features leaves this hypothesis unproven. Previous investigations, which included X-ray diffraction, differential thermal analysis, optical mineralogy studies, and FT-IR spectral measurements, have been unable to confirm the association of the pit features with fire. Calibrated radiocarbon dates place the use of the site at 5500-5300 BP. We applied optical dating and thermoluminescence (TL) dating to the hardened red layer and the overlying fill sediments, in order to determine the last time of firing and/or exposure to sunlight of the two components of the feature. The premise driving our investigations is the fact that heated sediments will give the correct TL age. In contrast, unheated sediments will give an incorrect TL age far in excess of the depositional age, but will give a correct optical dating age. The TL analyses yielded ages of 5160 š380 years for the hardened rim and 24,600 š1600 years for the fill. Optical dating of the fill yielded an age of 5260 š380 years, which is in excellent agreement with the TL age on the rim. These results fulfil the hypothesized results precisely. On this basis, we conclude that the pit features at the Ashkelon Marina archaeological site were fire pits used in early copper smelting technology.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.