Natura Croatica Issue number: Natura Croatica, Vol. 25 No.1

Najmlađi stadij u razvitku Dinarske karbonatne platforme: Gornji Numulitni Vapnenci u predgornom bazenu sjeverne Dalmacije, srednji Eocen, Hrvatska

Authors: Ljubomir Babić, Jožica Zupanič

Authors and affiliation

  • Ljubomir Babić Rokov perivoj 5, 10000 Zagreb, Croatia
  • Jožica Zupanič Rokov perivoj 5, 10000 Zagreb, Croatia

Abstract

The paper provides a description of the poorly known Upper Nummulitic Limestones exposed in the North Dalmatian foreland basin of the Outer Dinarides in Croatia. This formation originated on a land-attached ramp-type platform with a temperate sediment production. It transgressively overlies older platform limestones and includes limestones deposited in very shallow, restricted settings, which subsequently evolved into carbonate platform environments typified by diversified biota. The succession terminated at a drowning unconformity, which is intra-Bartonian (Middle Eocene) in age based on biostratigraphic interpretations of the larger foraminifera present. This study demonstrates that the history of the carbonate platform of the Outer Dinarides extends into the Bartonian and that the studied limestones document the youngest, hitherto unknown stage in the platform development. The SW margin of the Upper Nummulitic platform was dissected by faults and prone to collapse, which represented the source for megabreccias deposited in an adjacent basin. This platform-basin system represents a new element in the sedimentary and tectonic evolution of the Dinaric foreland.

Keywords

carbonate platform, drowning unconformity, foreland basin, megabreccias, Eocene, Outer Dinarides