The Upper Triassic - Lower Jurassic Vinding and Gassum Formations of the Norwegian-Danish Basin

Abstract

The late Triassic-early Jurassic Vinding and Gassum Formations are redefined and mapped within the Norwegian-Danish Basin. The Vinding Formation is a brackish marine shallow water deposit restricted to the Danish Subbasin. It is of late Norian-Rhaetian age. The Gassum Formation is a fluvio-deltaic to near-shore marine, arenaceous deposit carried from north and east into the basin. Its upper part is diachronous, ranging in age from Rhaetian in the basin center to late Sinemurian in the northern margin. It is proposed that the Ullerslev Formation is repealed. The parallelism between the course of sedimentation in the Norwegian-Danish Basin, the North German Basin and the Polish Basin indicates eustatic sea level changes to be of greater importance than local tectonic events.

A Geothermal Plant from a Time-Scale Perspective

“…Therefore, it constitutes an updated zonation of the Gassum formation in the Sønderborg area. It is important to highlight that the zonation presented in Table 1 is similar to the one presented by Bertelsen [10]. In other words, USd corresponds to G-1 member, Sh to G-2 member, and LSd to G-3 member.…”

“…Larsen [9] interpreted the depositional environment of the Gassum formation as deltaic. Subsequent, Bertelsen [10] subdivided the Gassum formation into three members based on a re-evaluation of existing wire-line logs, lithological and biostratigraphical reports. The lower G-1 member is an upwards coarsening unit of claystone, siltstone, and relatively well-sorted, fine-to coarse-grained sand with angular to sub-angular grain forms.…”

Evaluation of the quality, thermal maturity and distribution of potential source rocks in the Danish part of the Norwegian–Danish Basin

“…In Early Triassic times, the depositional environment changed to more continental conditions. Similarity in depositional facies in the North German and Norwegian-Danish Basins indicates that the two basins were connected, at least periodically (Bertelsen 1978;Michelsen & Clausen 2002). The facies encountered in the Jelling-1 and Grindsted-1 wells located on the northern flank of the Ringkøbing-Fyn High belong to the Bunter Shale, Bunter Sandstone, Ørslev, Falster and Tønder Formations; these formations may be traced farther northwards to the Mors-1 The SBs bound the named sequences (e.g.…”

“…Jelling-1 This study focuses on an evaluation of source rocks in the Danish part of the Norwegian-Danish Basin, which is largely equivalent to the Danish Embayment and the Danish Subbasin of earlier workers (Figs 1, 2; Sorgenfrei & Buch 1964;Larsen 1966;Michelsen 1975Michelsen , 1978Michelsen , 1989aBertelsen 1978). The Danish part of the Norwegian-Danish Basin (referred to hereafter as 'the study area') covers onshore Denmark and Danish offshore territory extending as far west as the eastern margin of the Danish Central Graben in the North Sea.…”

“…A gradual change to more humid conditions took place in Late Triassic times, associated with an Early Norian marine transgression that probably came from the south and resulted in the formation of a large epicontinental sea. The transgression led to deposition of oolitic limestones succeeded by marlstones and fossiliferous claystones of the Vinding Formation, which is typically 40-100 m thick over most of the basin (Figs 8-10;Bertelsen 1978Bertelsen , 1980Nielsen 2003). At its maximum extent in Late Norian times, the shallow sea covered most of the central basin and the Ringkøbing-Fyn High, whereas deposition of fluvial arkosic sands and lacustrine muds of the Skagerrak Formation continued in the Sorgenfrei-Tornquist Zone and on the Skagerrak-Kattegat Platform.…”