Trine Edvardsen defends her Ph.D. at Geological Museum

Candidate

Trine Edvardsen

Title

Upper Cretaceous and Danian foraminiferal stratigraphy and ecology recorded in the Dalbyover-1 core and Quarry, Denmark

Thesis summary

The chalk and other associated carbonate rocks deposited during the Maastrichtian and Danian, 72 – 61 million years ago, have been studied in great detail from numerous outcrops and shallow boreholes throughout Denmark. The majority of these studies, however, have focused primarily on the more proximal deposits exposed in eastern and northern Denmark, and less attention has been given to those more distal and deeper in the central parts of the Danish Basin. This thesis presents the first data from a newly drilled shallow core, Dalbyover-1, from the central parts of the Danish Basin in eastern Jylland, Denmark, and the first macrofauna analysis of the mid Danian succession in the nearby Dalbyover Quarry.

The aim of this thesis is to document the biotic changes recorded in samples from the Dalbyover core and quarry, with special emphasis on the microfossil assemblages (foraminifera). The study is based on detailed sedimentological and micropalaeontological analysis of two specific time intervals recorded in the material: the time leading up to and during deposition of the uppermost Maastrichtian Kjølby Gaard Marl, a distinct lithological shift in the succession interpreted to represent a brief warming period in the latest Maastrichtian; and the Paleogene succession spanning the Cretaceous-Paleogene boundary to the mid Danian. The foraminiferal observations are integrated with nannofossil stratigraphy, and isotopic- and gamma-ray data, enabling detailed correlation of the studied succession with outcrops and boreholes throughout the Danish Basin.

Supervisor

Professor Lars Stemmerik, Natural History Museum of Denmark, University of Copenhagen

Co-supervisor

Researcher Jan Audun Rasmussen, Museum Mors, Nykøbing Mors

Assessment committee

Associate professor Arne Thorshøj Nielsen (chairman), Department of Geosciences and Natural Resource Management, University of Copenhagen

Professor Marit-Solveig Seidenkrantz, Department of Geoscience, Aarhus University

Associate professor Caterina Morigi, Department of Earth Sciences, University of Pisa