Geological and structural map of the southeastern Pag Island, Croatia: field constraints on the Cretaceous - Eocene evolution of the Dinarides foreland

Silvia Mittempergher,Marco Meda,Andrea Succo,Pierre Olivier Bruna,Andrea Bistacchi,Fabrizio Storti

doi:10.3301/gft.2019.06

Abstract

The sedimentary succession exposed in the Northern Dalmatia Islands mainly consists of Cretaceous to Neogene shallow water carbonates, folded and imbricated within the External Dinarides thrust belt. During Cretaceous times, carbonate sediments were deposed on a heterogeneous, tectonically-influenced carbonate platform, which was then uplifted and eroded, as evidenced by a regional unconformity embracing the Late Cretaceous and Paleocene. Sedimentation resumed during the Eocene, when the area was part of the foreland basin of the Dinaric belt. With our geological and structural map of the southeastern Pag Island at the 1:25,000 scale, we refined the stratigraphic and structural setting and the tectono- sedimentary evolution of the area.

Highlights

The hanging wall of the outermost Dinaric thrust is an imbricated belt of deformed Cretaceous to Neogene sediments (Figure 1; External Dinarides after Pamić et al, 1998), which recorded the transition from a long-lasting carbonate platform to a laterally heterogeneous Eocene – Oligocene foreland basin (e.g., Tari, 2001; Korbar, 2009; Vlahović et al, 2012)
The Santonian - Ypresian sedimentary hiatus registered at the Pag Island is among the longest in the Dalmatian Islands (Jelaska et al, 1994; Korbar, 2009), it is difficult to constrain the age and geodynamic context of the preunconformity faults. iii) Dinaric foreland basin (Ypresian - Lutetian): the erosive surface truncating the Gornji Humac Formation constitutes the bedrock of the Eocene to Oligocene foreland basin of the Dinaric belt
Since the Ypresian, the study area underwent a marine transgression leading to the deposition of the ramp carbonates of the foraminiferal limestone in a shallow foredeep setting, with a paleobathimetry controlled by the retreating forebulge (Babić and Zupanič, 2016)

Summary

Methods and techniques

The sedimentary succession exposed in the Northern Dalmatia Islands mainly consists of Cretaceous to Neogene shallow water carbonates, folded and imbricated within the External Dinarides thrust belt. During Cretaceous times, carbonate sediments were deposed on a heterogeneous, tectonically-influenced carbonate platform, which was uplifted and eroded, as evidenced by a regional unconformity embracing the Late Cretaceous and Paleocene. Sedimentation resumed during the Eocene, when the area was part of the foreland basin of the Dinaric belt. With our geological and structural map of the southeastern Pag Island at the 1:25,000 scale, we refined the stratigraphic and structural setting and the tectonosedimentary evolution of the area

Introduction

Discussion