Srednjoeocenska starost navodnih oligocenskih sedimenata u flišu Pazinskoga bazena (Istra, Vanjski Dinaridi)

• Main Authors: Babić, Lj., Hernitz-Kučenjak, M., Ćorić, S., Zupanič, J.
• Format: Text
• Language: English
• Published: Croatian Natural History Museum 2007
• Subjects: Eocen; Oligocen; planktonske foraminifere; nanoplankton; fliš; Pazinski bazen; Istra; Hrvatska; Eocene; Oligocene; planktonic foraminifera; nannoplankton; flysch; Pazin Basin; Istria; Croatia; Planktonic foraminifera
• Online Access: http://hrcak.srce.hr/18758; http://hrcak.srce.hr/file/29206

Dosadašnja istraživanja i shvaćanja, kako o starosti, tako i karakteru slijeda sedimenata fliša Pazinskoga bazena u Istri, upućivala su na ukupnu starost fliša od kasnoga lutecija do starijega priabonija. Međutim, nedavno su prikazani podaci, prema kojima jedan dio tih sedimenata odgovara kasnom oligocenu, što je bitna novost za razmatranje razvitka toga bazena, kao i orogena Dinarida. Ovaj rad odgovara na potrebu dodatne provjere starosti tih sedimenata zbog važnosti odnosnoga datiranja. Prikazani rezultati temelje se na usporedbi karaktera i slijeda sedimenata iz predjela odakle potječu nedavni podaci o oligocenu sa sedimentima drugih dijelova Pazinskoga bazena, te na biostratigrafskom datiranju pomoću planktonskih foraminifera i nanoplanktona. Ustanovljene biozone odgovaraju gornjem luteciju i donjem bartoniju, dakle, donjemu dijelu ukupnoga raspona starosti Pazinskoga fliša. The dating of the flysch sediments of the coastal Dinarides is critical for considering the evolution of the Dinaric chain. The flysch of the Pazin Basin, Istria has been considered to be Late Lutetian to Late Eocene in age by many workers. The recently reported Late Oligocene age of a part of this flysch (ŠPARICA et al., 2005) is highly relevant when considering the sedimentary and tectonic evolution of the area, as well as the western Dinarides in general. The importance of the Late Oligocene dating, and the character of the succession of the area in question, which shows similarities with Middle Eocene sediments in other parts of the basin, provoked the need for a reevaluation of the dating of these specific sediments. The results presented here support the Middle Eocene age of these sediments, which is consistent with the dating proposed by previous workers, and agrees with the character of the relevant sedimentary succession.