Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 2. 1970-71. (Budapest, 1971)

As judged from the benthonic and planktonic foramlnifers present, this biofacies is identifiable with the assemblage living between 100 and 220 m depth in the Adriatic Sea. The most probable value is about 150 m. Accordingly, one can assume the existence of a NW-SE oriented, 20 km long, 6 km wide, graben-like depression between Andornaktálya and Kacs. Relying upon drilling record, it can be well delimited towards North; the southern margin,however

, is rather uncertain. No Upper Eocene is known to occur in the vicinity of Tard; near Mezőkeresztes, the limestone facies has developed. So it may be assumed that the southern boundary of the graben is situated to the North from Tard. At the Eocene/Oligocene boundary, crustal movements occurred in the Bükk Mountains region. A vigorous uplift started East of the Egerszalók-Bükkszék line, restulting most probably in the emergence of the territory lying between Egerszalók and Noszvaj. (The Tard facies is poorly developed and the horizon of small Globigerinae is missing.

) The graben between Andornaktálya and Kacs began to emerge; the poorly developed facies of small Globigerinae is overlain by the Tard facies devoid of foramlnifers (deposited in shallow, stagnant, poorly oxygenated water). West of the Egerszalók-Bükkszék line, the geological evolution took a rather different course, as it could be deciphered even from the unfortunately very scarce data. The Late Eocene water depth remained unchanged here; sediments with small Globigerinidae were deposited even then,when farther to the East already the Tard facies has become characteristic. This assumption is supported by the fact that the latter facies reveals a consequent variation in thickness: 40 to 70 m at Demjén, 586 m at Tard itself, 427 m at Mezőkeresztes, and over I50 m at Szomolya.