Rafowe utwory miocenu z Roztocza zachodniego

Abstract

MIOCENE REEF DEPOSITS OF THE WESTERN ROZTOCZE Summary Three genetically different types of Miocene reefs are described from the western Roztocze. Algal-vermetid reefs with rich micro- and macrofaunal assemblages are mainly built by calcareous algae of the genus Lithophyllum and sessile gastropods Vermetidae. These reefs are characterized by strong synsedimentary cementation and a large contribution of “internal sediments”. Oyster reef from Zdziechowice is built of representatives of the species Ostrea “cochlera” (Poli). The two reef types originated in very shallow normal marine environment. Cryptoalgal-serpulid reefs, built of strongly porous pelletal-micritic limestones, represent products of multilateral activity of blue-green algae. Reefs of this type originated in marine environment with physico-chemical parameters markedly diverging from the normal. They are accompanied by monotonous assemblage of micro- and macrofauna.