Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 5. 1974. (Budapest, 1974)
The five species (Turborotalia opima opima , T. obesa , Globigerina ouachitaensis ciperoensis, G. angulisuturalis and Globigerinoides primordius) appearing in the Oligocène of Hungary are illustrated in Fig. 3. The appearance data are based on the works of BLOW (1969), BOLLI (1956b, 1966), BERGGREN (1969b), CICHA et al. (1971) and on my own observations, taking the absolute age data of BERGGREN (1971) into consideration. Only the Oligocène/Miocene boundary has been lowered, because in the light of the data derived from Central Europe, the 22, 5 m.y. of BERGGREN seems to be a little exaggerated. It is clear from Fig. 3. that the earliest appearance data of the subspecies Globigerina ouachitaensis ciperoensis fall within tropical regions (the data of BLOW and BOLLI coincide), then appears in the Apennines somewhat later, and in Northern Europe in the lower part of the Rupelian, i.e. in the equivalent of P 20. The species migrated into Hungary from the North, because it appears even later. Globigerina angulisuturalis is a good index species in the tropical and Mediterranean regions: Its appearance agrees both in Italy and Trinidad. However, at that time in the Carpathian basin only transitional forms from Globigerina anguliofficinalis can be found. According to CICHA et al. (1971) the typical forms can be recognized only from the middle part of the Upper Oligocène onwards . In Northern Europe the transitions appear in the upper part of the Late Oligocène, and the typical forms are unknown from the Oligocène . The earliest appearance of the subspecies Turborotalia opima opima is in the Apenniras, it reached tropical regions within 1 m. y., but it needed 2 1/2 m. y. to migrate nto the Carpathian basin (where it appears only from the Rupelian/Egerian boundary onwards), and invaded Northern Europe as late as the middle Late Oligocène. These great differences can be explained by climatic barriers. According to BOLLI (1957b), the appearance of- Turborotalia obesa on Trinidad fall s within the Catapsydrax dissimilis Zone of the Miocene . In all Central European Inner-Carpathian basins the earliest typical specimens appear at the Rupelian/Egerian boundary (CICHA et al. 1971). BUTT (1966) recorded this species from the Upper Oligocène of the Aquitanian Basin. According to some authors, the Globigerinoides datum marks the Oliocene/Miocene boundary. On the other hand there are-some records suggesting the Late Oligocène existence of this genus (BUTT 1966, Aquitanian Basin; CICHA et al,1971, Inner-Carpathian basins). These latter authors recognized the first Globigerinoides forms at the basal Egerian, and the abundance of this genus in the Upper Egerian. The Hungarian basal Egerian also yielded some specimens. Similar differences result from the comparison of the planktonic zones with the nannoplankton horizons. MÜLLER (1970) found that on Trinidad the Globigerina ampliapertura and Globorotalia opima opima planktonic foraminiferal zones correspond to the Sphenolithuspredistentus and Sphenolithus distentus nannoplankton zones, respectively. The former nannoplankton zones correspond to the Lower and Upper Rupelian of Northern Europe, respectively. It is generally admitted and is supported also by the evolutional grade of the fauna,
