Geological investigations on sediment core Lz1120 from Lake Ohrid

Magnetic susceptibility investigations show rather high magnetic values throughout the core, with peaks unrelated to the occurrence of tephra layers but instead to the relative abundance of detrital magnetic minerals in the sediment. Naked-eye inspection of the core allowed us to identify of two tephra layers, at 896-897 cm and 1070-1075 cm.

Laboratory inspection of the grain-size fraction >125 µm allowed for the identification of a third cryptotephra at 310-315 cm. Major element analyses on glass shards of the tephra layers at 896-897 cm and 1070-1075 cm show a trachytic composition, and indicate a correlation with the regionally dispersed Y-3 and Y-5 tephra layers, dated at ca 30 and 39 cal ka BP. The cryptotephra at 310-315 cm has a mugearitic- benmoreitic composition, and was correlated with the FL eruption of Mt.