Eighteen rain samples from Israel have been analyzed for their chemical composition and 87Sr 86Sr ratios. The Sr-isotopic ratios lie in the range 0.7078 and 0.7092, and the Sr concentrations vary from 1 × 10-4 to 9 × 10-4 meq Sr/l. Soluble salts in rainwater are inherited from three major natural sources, seaspray, Recent marine minerals and mineral dust eroded from rock outcrops and soil. A mixing model is formulated to apply the chemical composition of rain (Cl- and Sr2+) and its isotopic 87Sr 86Sr ratio, for the identification and estimation of the Sr sources. All the samples fall within the mixing space predicted by the model for the three end members mentioned above. The data indicate that the most important non-seaspray source contributing dissolved salts to the rains in Israel comprises a mixture of Senonian to Eocene chalk (and its weathering products) and Recent marine minerals, from local and imported sources. Most of the samples (67%) contain 50% or more non-seaspray Sr (i.e., Sr dissolved from dust or Recent marine minerals), whereas 56% of the samples display 87Sr 86Sr ratios lower than 0.7090. The rest represent mixtures of seaspray and Recent marine minerals.
Bibliographical noteFunding Information:
We wish to thank Mrs. Tikva Brown for her technicaal ssistancein the Sr separationfo r the isotopica nalysisa, nd Mr. Zvi Tirosh for his help in samplingt he rain. We have greatlyb enefited from the excellent reviewing work of W.C. Graustein(Y ale) and of Ph. Negrel and G. Man-hes (Paris).T he help of an anonymourse vieweirs also acknowledgedP.a rtial funding of the study was provided by the joint German-Israelrie - searchf und(BMFT/MOST, projectD ISUM-20).
ASJC Scopus subject areas
- Geochemistry and Petrology
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science