scholarly journals Lower Cretaceous calcareous nannofossil biostratigraphy in the Danish Central Trough

1987 ◽  
Vol 20 ◽  
pp. 1-89
Author(s):  
Erik Thomsen
Keyword(s):  
North Sea ◽  
Lower Cretaceous ◽  
Calcareous Nannofossils ◽  
Northern Germany ◽  
The North ◽  
Lower Aptian ◽  
Upper Hauterivian ◽  
Central Trough ◽  
The North Sea ◽  
Calcareous Nannofossil Biostratigraphy

Calcareous nannofossils are described from Lower Cretaceous strata of four borings in the Central Trough of the Danish North Sea sector, and from three Aptian units on Helgoland and at Sarstedt, northern Germany. The assemblages range in age from Upper Hauterivian to Albian-?Cenomanian. Abundances of calcareous nannofossils varied considerably throughout the investigated sequences. They were rock-forming in several Lower Barremian - Aptian sediments, but rare or lacking in many of the Hauterivian and Albian strata. The Middle Barremian - Lower Aptian assemblages were often dominated by nannoconids. Preservation was generally bad in chalk and good in marl deposits. Some finely laminated black sediments yielded extremely well-preserved assemblages. One hundred and sixteen species were recognized. Eighteen species were selected as biostratigraphically particularly useful and their chronostratigraphic ranges are shown and discussed. The ages of the investigated sequences were determined on the basis of the selected nannofossil events. Some distinct sedimentary units in the North Sea could be correlated with time-equivalent formations in eastern England and northern Germany.

Late Palaeozoic to Early Cenozoic geological evolution of the northwestern German North Sea (Entenschnabel): New results and insights

2014 ◽  
Vol 93 (4) ◽  
pp. 147-174 ◽  
Author(s):  
Jashar Arfai ◽  
Fabian Jähne ◽  
Rüdiger Lutz ◽  
Dieter Franke ◽  
Christoph Gaedicke ◽  
...  
Keyword(s):  
North Sea ◽  
Lower Cretaceous ◽  
Late Jurassic ◽  
Structural Element ◽  
The North ◽  
Sedimentary Evolution ◽  
Basin Subsidence ◽  
The North Sea ◽  
Thickness Variations ◽  
Zechstein Salt

AbstractThe results of a detailed seismic mapping campaign of 13 horizons in the northwestern German North Sea, covering Late Permian to Palaeogene sedimentary successions, are presented. Based on the interpretation of four 3D and two 2D seismic surveys, thickness and depth maps of prominent stratigraphic units were constructed. These maps provide an overview of key structural elements, the sedimentation and erosion, and give insights into the evolution of the German Central Graben. The base of the Zechstein Group reaches a maximum depth of 7800 m within the German Central Graben. Lateral thickness variations in the Zechstein reflect the extensive mobilisation of Zechstein salt. Complex rift-related structures, with the Central Graben as the main structural element, were found not later than the Early Triassic. Up to 3000-m thick Triassic sediments are preserved in the eastern German Central Graben of which 1800 m consist of Keuper sediments. The Lower Buntsandstein unit shows increasing thicknesses towards the southeastern study area, likely related to distinct lateral subsidence. As a consequence of uplift of the North Sea Dome, Middle Jurassic sediments were eroded in large parts of the northwestern German North Sea and are only preserved in the German Central Graben. The NNW–SSE oriented John Basin is another important structural element, which shows maximum subsidence during the Late Jurassic. In most parts of the study area Lower Cretaceous sediments are absent due to either erosion or non-deposition. Lower Cretaceous deposits are preserved in the Outer Rough Basin in the northwest and within the German Central Graben. Upper Cretaceous sediments are found at depths between 1500 and 3600 m, reaching a maximum thickness of approximately 1600 m on the Schillgrund High. Contraction and inversion of pre-existing Mesozoic faults during the Late Cretaceous is distinct at the Schillgrund Fault, i.e. the eastern border fault of the Central Graben. The Palaeogene is predominantly a period of strong basin subsidence. Within 37 Myrs, up to 1400 m of Palaeogene sediments were deposited in the northwesternmost part of the study area. Detailed mapping of salt structures enables a reconstruction of halokinetic movements over time and a deciphering of the influence of the Zechstein salt on the sedimentary evolution during the Mesozoic and Cenozoic. Increasing sediment thicknesses in rim-synclines indicate that most of the salt structures in the German Central Graben had their main growth phase during the Late Jurassic.

Calcareous nannoplankton and the age of the Globigerina silts of the western approaches of the English Channel

1974 ◽  
Vol 111 (4) ◽  
pp. 303-306 ◽  
Author(s):  
E. Martini
Keyword(s):  
Atlantic Ocean ◽  
North Sea ◽  
English Channel ◽  
Calcareous Nannoplankton ◽  
Northern Germany ◽  
Lower Miocene ◽  
The North ◽  
The North Sea

SummaryCalcareous nannoplankton from the Globigerina silts of the western approaches of the English Channel indicate the presence of standard nannoplankton zones NN2, NN 4 and NN 5, part of which can be correlated with Neogene beds in Belgium and Northern Germany. The calcareous nannoplankton support the possibility of a connexion between the North Sea Basin and the Atlantic Ocean through the English Channel during part of the Lower Miocene.

Carboniferous-Permian rifting and magmatism in southern Scandinavia, the North Sea and northern Germany: a review

2004 ◽  
Vol 223 (1) ◽  
pp. 11-40 ◽  
Author(s):  
Else-Ragnhild Neumann ◽  
Marjorie Wilson ◽  
Michel Heeremans ◽  
Elizabeth Ann Spencer ◽  
Karsten Obst ◽  
...  
Keyword(s):  
North Sea ◽  
Northern Germany ◽  
The North ◽  
Southern Scandinavia ◽  
The North Sea

scholarly journals Mid-Paleocene palaeogeography of the Danish area

2002 ◽  
Vol 49 ◽  
pp. 171-186
Author(s):  
Ole R. Clausen ◽  
Mads Huuse
Keyword(s):  
North Sea ◽  
Upper Cretaceous ◽  
Marked Change ◽  
Tectonic Uplift ◽  
The North ◽  
Central Trough ◽  
Regional Tectonic ◽  
The North Sea

At the Danian/Selandian transition the North Sea Basin experienced a marked change, from deposition of almost pure carbonate during the Upper Cretaceous and Danian to deposition of greensand, marl and clay during the Selandian. Erosional features at the Top Chalk surface and the occurrence of an overlying conglomerate (transgressive lag deposit) indicates that large parts of the Danish area were subaerially exposed at the Danian/Selandian transition, probably due to regional tectonic uplift. Tectonically induced inversion of fault trends in the Central Trough and the Sorgenfrei- Tornquist Zone and differential relative subsidence between the Ringkøbing-Fyn High and the Norwegian-Danish Basin strongly affected the distribution of the lower Selandian sediments. Three palaeogeographic maps are presented to illustrate the various stages of the early Selandian transgression in order to demonstrate the mid-Paleocene evolution of the Danish area.

scholarly journals The Innes Field, Block 30/24, UK North Sea

2020 ◽  
Vol 52 (1) ◽  
pp. 488-497 ◽  
Author(s):  
J. G. Gluyas ◽  
P. Arkley
Keyword(s):  
North Sea ◽  
Oil And Gas ◽  
Upper Jurassic ◽  
The North ◽  
Start Up ◽  
Central Trough ◽  
The North Sea ◽  
Water Cut ◽  
The Uk ◽  
Oil Company

AbstractThe abandoned Innes Field was within Block 30/24 on the western margin of the Central Trough in the UK sector of the North Sea. Hamilton Brothers Oil Company operated the licence, and Innes was the third commercially viable oil discovery in the block after Argyll and Duncan. It was discovered in 1983 with well 30/24-24. Three appraisal wells were drilled, one of which was successful. Oil occurs in the Early Permian Rotliegend Group sandstones sealed by Zechstein Group dolomites and Upper Jurassic shale.The discovery well and successful appraisal well were used for production. Export of light, gas-rich crude was via a 15 km pipeline to Argyll. Innes was produced using pressure decline. It was abandoned in 1992 having produced 5.8 MMbbl of oil and possibly 9.8 bcf of gas. Water cut was a few percent.Innes was re-examined between 2001 and 2003 by the Tuscan Energy/Acorn Oil and Gas partnership with a view to tying the field back to the newly redeveloped Argyll (Ardmore) Field but marginal economics and financial constraints for the two start-up companies prevented any further activity. Enquest currently owns the licence and the company has redeveloped Argyll/Ardmore, as Alma. There are no plans to redevelop Innes.

scholarly journals Preface

1991 ◽  
Vol 16 ◽  
pp. 5-5
Author(s):  
Nils Frandsen
Keyword(s):  
North Sea ◽  
Working Group ◽  
Geological Survey ◽  
The North ◽  
Central Trough ◽  
Southern Central ◽  
The North Sea ◽  
Lithostratigraphic Correlation

In June 1989, Dansk Olie- og Gasproduktion A/S (DOPAS) sponsored a well-attended symposium on the Jurassic in the Southern Central Trough held at the DOPAS premises in Hørsholm, Denmark. The background for the symposium was a desire among geologists working in the Dutch, German and Danish sectors of the North Sea to establish a forum to discuss problems of lithostratigraphic correlation across the sector boundaries and eventually arrive at a common nomenclature. A number of lectures were held at the symposium and an informal working group was established to deal with the details of lithostratigraphic correlation. The present publication, sponsored partly by DOPAS and partly by the Geological Survey of Denmark (DGU), contains extended abstracts of the lectures.

Sign in / Sign up

Export Citation Format

Share Document