Az Eszterházy Károly Tanárképző Főiskola Tudományos Közleményei. 1994. Sectio Geographiae.(Acta Academiae Paedagogicae Agriensis : Nova series ; Tom. 21)

Dávid Árpád: Palaeo-occological and palaeo-pathological observations on upper oligocene molluscs (Eger, Hungary)

DÁVID ÁRPÁD PALAEO-OECOLOGICAL AND PALAEOPATHOLOGICAL OBSERVATIONS ON UPPER OLIGOCENE MOLLUSCS (EGER, HUNGARY) ABSTRACT: The most noteworthy geological exposure in NorthHungary can be found in Eger (Hungary). The Upper-Oligocene beds in the claypit of the former "Wind" brickworks have an abundant fossil content. On the basis of scientific investigations of remains of molluscs, the author has made a series of palaeoecological and palaeopathological observations. The quantity and preservation of the shells, the various forms of symbiosis, the bio-erosive activity of caustic sponges, the presence of Bryozoan-colonies, the traces of boring-bivalves, the perforation-marks of predatory snails, cicactries caused by crabs all refer to a former shallow-water marine environment. INTRODUCTION A famous geological outcrop in North-Hungary can be found in Eger, in a brickyard's clay-pit situated at the south-east part of the town. The 120 m thick deposits are mentioned as the "Wind factory" beds in the special literature. Four stratigraphic units can be distinquished in this section: 1. Glauconitic-tufiltic sandstone and marl. 2. The glauconitic-tuffitic series is overlain by Molluscan Clay. 3. Alternating beds of sandstone and clay of shallow-sublittoral origin. 4. Series of littoral and lagoonal coarse sand and clay. 33