GYPSUM AS REPLACEMENT OF SILICIC TUFF (TEPHRA OR PUMICE) - BARDAWIL LAGOON, EASTERN MEDITERRANEAN

Gypsum has replaced a tuff (tephra) or pumice in Bardawil Lagoon, a hy persaline body of water in the eastern Mediterranean off the coast of the Sinai Peninsula. The gyprock is a vugular pure gypsum. This rock w as initially mistaken for pumice; its vesicular texture suggested larg e-scale degassing. It is composed of angular and worn gypsum clasts bo unded together by a gypsum cement. The texture is unlike that of any g ypsum rock yet described. The initial tuff (tephra) or pumice, now rep laced by gypsum, may be related to the most powerful eruption in recor ded history, the Thera/Santorini eruption which spread over much of th e eastern Mediterranean.