Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 5. 1974. (Budapest, 1974)

Definition: From the extinction of the Turborotalia cerroazulensis cocoaensis up to the first Globigerina tapuriensis . Remarks: By its original designation this zone comprises the topmost Upper Eocene and the basal Oligocène. According to the modified definition of BLOW (1969) Globigerina gortanii gortanii/ Globorotalia /T./ centralis Zone) this zone includes only the topmost Eocene, because the Globigerina tapuriensis, a species characterizing the upper boun­dary of the new zone, appears in the designation area at the Eocene/Oligocene boundary. The present modification is due to the fact that Crib rohan tkenina inflata (HOWE) which marks by BLOW and BANNER with its extinction the lower boundary of the zone, does not occur in Hungary. On the other hand the disappearance of the Turborotalia cerroa­ zulensis group used by BAUMANN (1970) to replace Cribrohantkenina inflata, occurs ­according to BLOW (1969) - after that of this latter species. On the other hand it is pro­ved, that the Globigerina tapuriensis datum falls within the Eocene in Northern and Central Europe. The study of the temporary excavation site at the Hunyadi Stairs of Buda Castle Hill has revealed that Turborotalia aff . centralis appears in the lower part of the zone.Common species in this zone are Subbotina linaperta , S. eocaena, Globigerina tripartita , Turbo­rotalia increbescens. Transitional forms between Turborotalia increbescens and Glo­bigerina ampliapertura, as well as typical G. ampliapertura also occur. In the upper­most part of the zone the typical form o f Globigerina ouachitaensis gnaucki appears. The total thickness of the zone is unknown for lacking a complete profile so far. Turborotalia increbescens Zone Author : SZTRÁKOS, 1974c. Definition: From the first Globigerina tapuriensis up to the disappearance of the bulk of the Mediterranean species. Remarks : On the basis of the definition the upper boundary of the zone is difficult to draw. The mentioned Mediterranean species are Turborotalia increbescens, Subbotina eocae­ na group and Globigerina tripartita . On the basis of Borehole Rózsadomb-8/3. these forms, owing to their different ecological requirements, disappear at different parts of the profile. The most sensitive species is Turborotalia increbescens , a species of gre­ater frequency in the lower part of the zone, with a gradual decrease upwards and dis­appearing at 7 m below the upper boundary of the zone . This zone yields the other spe­cies with great quantity, but some specimens regularly occur also in the lower part of the overlying, Globigerina postcretacea Zone. The frequency distribution of the species is variable along the profile. In the lowest part the dominant species are Subbotina eocaena , Globigerina tripartita an d Turborotalia in­ crebescens ; these are followed by an assemblage with dominant Subbotina angiporoides and with associated S. eocaena , but in certain beds Turborotalia liverovskae and the Chiloguembelina species are also common. In the uppermost part of the zone the com­monest and second-commonest forms are Globigerina angustiumbilicata and Turborota-

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