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Tracing the Source of the Elephant And Hippopotamus Ivory from ...

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Israel<br />

Published strontium isotope data <strong>from</strong> Israel are available, but <strong>the</strong> geological<br />

coverage is less than ideal. The coastal areas are <strong>of</strong> primary interest for Israel, since <strong>the</strong>se<br />

regions are where hippopotami would have once dwelled. However, <strong>the</strong> rest <strong>of</strong> Israel<br />

will be considered as well.<br />

Ayalon et al. (1999) sought to reconstruct <strong>the</strong> palaeoclimate <strong>of</strong> <strong>the</strong> eastern<br />

Mediterranean region based on δ 18 O and δ 13 C variations in speleo<strong>the</strong>ms <strong>from</strong> Soreq Cave<br />

in Israel, about 40 km inland <strong>from</strong> <strong>the</strong> coast. They noticed an increase in isotopic ratios<br />

during colder and drier periods, and established that strontium isotopes, like oxygen<br />

isotopes, can be influenced by climatic factors (Ayalon et al. 1999: 715, 719). More<br />

important for <strong>the</strong> purposes <strong>of</strong> this <strong>the</strong>sis, however, <strong>the</strong>y found <strong>the</strong> local dolomite host<br />

rock to have a 87 Sr/ 86 Sr ratio <strong>of</strong> 0.70745, and <strong>the</strong> Holocene values <strong>from</strong> <strong>the</strong> speleo<strong>the</strong>ms<br />

to range <strong>from</strong> 0.7079 to 0.70825, with <strong>the</strong> majority around 0.70822. These values are<br />

reproduced in Figure 47 (solid yellow triangles). The disparity between <strong>the</strong> dolomite host<br />

rock and <strong>the</strong> speleo<strong>the</strong>ms is attributed to exogenic sources to <strong>the</strong> speleo<strong>the</strong>m such as sea<br />

spray and aeolian dust (Ayalon et al. 1999: 720). Ano<strong>the</strong>r article by <strong>the</strong> same group <strong>of</strong><br />

researchers sees <strong>the</strong> strontium isotope ratios as influenced by “major changes in <strong>the</strong><br />

temperature, <strong>the</strong> mean annual rainfall and its isotopic composition, <strong>the</strong> isotopic<br />

composition <strong>of</strong> <strong>the</strong> Mediterranean vapor source, <strong>the</strong> soil moisture conditions, and in <strong>the</strong><br />

mixing proportions <strong>of</strong> sources with different 87 Sr/ 86 Sr ratios (sea spray, dust particles and<br />

dolomitic host rock)” (Bar-Mat<strong>the</strong>ws et al. 1999: 85). However, a correlation between<br />

strontium isotope ratios and climate may only be encountered in special geological<br />

situations like that <strong>of</strong> speleo<strong>the</strong>ms.<br />

135

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