Rajko PAVLOVEC

Oddelek za geologijo, Naravoslovnotehniška fakulteta, SI-1000 Ljubljana, Aškerčeva 2

IZVLEČEK

Pri Fiesi nedaleč od Pirana ob slovenski obali so v delu srednjelutecijskega apnenčevega turbidita številni numuliti. Večina pripada vrsti Nummulites millecaput, nekateri so tej vrsti podobni in bi jih ob boljšem materialu kazalo opisati kot novo vrsto ali podvrsto. Podane so pripombe k opisom numulitov iz različnih dežel.

Ključne besede: foraminifere, fliš, eocen, Slovenija

SINTESI

Nella torbidite calcarea medio-eocenica della località di Fiesso, situata sulla costa slovena, sono stati trovati numerosi nummuliti. La maggioranza di questi appartiene alla specie Nummulites millecaput. L'autore suppone che, avendo a disposizione materiale migliore, altri esemplari assomiglianti a tale specie potrebbero venir descritti come nuova specie o sottospecie. Nell'articolo vengono commentate le descrizioni di nummuliti provenienti da varie nazioni.

Parole chiave: foraminiferi, flysch, eocene, Slovenia

Rajko PAVLOVEC

Department of Geology, Faculty of Natural Sciences, SI-1000 Ljubljana, Aškerčeva 2

SUMMARY

In the calcareous turbidite between Fiesa, Strunjan and Izola along the Slovenian Adriatic coast (Fig. 1) occurs, especially in its lower part, an abundance of test of species Nummulites millecaput (Fig. 2). Megalospheric forms are prevalent. Along with them few discocyclinas occur, as well as rare assilinas and spicules of sea urchins, many lithothamnian fragments, several dentalia and nondeterminable fossils. In the lower 10 to 15 cm, the tests of nummulitids lie mostly at an angle of 45° to the stratification, whereas elsewhere they are almost paralell to it. Above this horizon lies a 10 to 15 cm thick bed consisting mainly of broken tests. Upwards the sediment are finer grained, limestone parts alternate with thin sandy intercalations. This is an indication of sorting of particles by size during transport by currents of smaller slumps. The profusion of nummulitid tests suggests that the material was supplied into the flysch sea especially from the part of the carbonate platform, on which many nummulites of the mentioned species lived. However, transport of this material occurred only sporadically.

Age of the beds is Middle Eocene. Pavšič and Peckmann (1996) attributed them close to the centre of biozone NP 16.

Numeric data for the species Nummulites millecaput are given in table 1. Most nummulits from Fiesa belong to this species (Pl. 1, Figs. 1-7). Table 2 contains data for similar forms (Nummulites aff. millecaput; Pl. 1, Figs. 8-9). These have a somewhat thinner marginal cord and somewhat higher whorls. Septa are more regular, a little less drawn backwards, and the protoconch is somewhat smaller. This is perhaps a new species or subspecies, but certain characteristics of the two forms overlap.

Since taxonomic marks of Lutetian representatives of the group Nummulites millecaput overlap, or they are very similar, we listed a few remarks to previous descriptions. Among others, a 19 cm large nummulite (Nummulites ? maximus) from the locality Kalo Chorio southeast of Iraklion on Crete is also mentioned. Unfortunately a single axial section was found that could not get isolated.

Key words: foraminifers, flysch, Eocene, Slovenia