EARLY HOLOCENE TEPHRA IN THE BOTTOM SEDIMENTS OF THE LATAKIA BASIN

Abstract

This work was aimed to study the bedding of Early Holocene sapropel and a thin (0.2-4 cm) layer of tephra enclosed in it at a distance of 5-8 to 13 cm above its bottom. The tephra consists of poorly rounded particles of volcanic material containing 18.9-35.3% of sand-, 54.0-70.4% of silt-, 10.7-15.9% of clay-size fractions, the amount of the sand-size fraction decreasing southward from the Midis Bank. The amount of volcanic glass in the tephra increases, and that of hornblende decreases, in the same direction. The tephra mineral composition is dominated by crystal-vitric tuff. The volcanic glass is vesicular, angular, of fanciful shapes. The accessory minerals are medium-silicic plagioclase (andesine), quartz, hornblende, and pigeonite. There are scarce fragments of silicate rocks. As follows from the petrographic, mineral, and chemical composition of the tephra, this material could not have been produced by volcanic eruptions that had occurred in the Aegean Sea or on the East-Mediterranean Ridge. Its presumable source had been a volcano located in the Cyrenia-Midis structural zone.