Nyker Group

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Nyker Group
Stratigraphic range: Latest Jurassic to Early Cretaceous, 146–140  Ma
Type Geological unit
Sub-units Rabekke Formation, Robbedale Formation, Jydegaard Formation
Underlies Arnager Greensand Formation
Overlies Bagå Formation
Lithology
Primary Claystone and Sandstone
Location
Region Bornholm
CountryFlag of Denmark.svg  Denmark

The Nyker Group is a group of geological formations from the Early Cretaceous, about 146 to 140 million years ago. It is on the island of Bornholm, Denmark. It includes the Rabekke, Robbedale and Jydegaard Formations. [1]

Contents

Rabekke Formation

The Rabekke Formation is the lowermost formation of the Nyker Group. It dates to about 146 to 145 million years ago, at the Jurassic-Cretaceous boundary. The formation has the significance of having the first Scandinavian mammal, Sunnyodon notleyi, uncovered from it. Many crocodilomorphs and other vertebrates have been recovered from it. [2]

Robbedale Formation

The Robbedale Formation is the middle formation of the Nyker Group. It dates to about 145 million years ago. No vertebrate fossils have been recovered from the formation. [1]

Jydegaard Formation

The Jydegaard Formation is the uppermost formation of the Nyker Group. It dates to around 145 to 140 million years ago. The first dinosaur found on Denmark, Dromaeosauroides bornholmensis, was discovered in this formation. [1] Many vertebrates have been recovered from it. [2]

See also

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Rabekke Formation

The Rabekke Formation is a geological formation dating to the latest Jurassic or earliest Cretaceous, around 146 to 145 million years ago. The formation crops out on the island of Bornholm, Denmark. Vertebrate fossils have been found in the formation.

Robbedale Formation

The Robbedale Formation is a geological formation dating to the Berriasian stage of the Early Cretaceous, about 142 million years ago. It is on the island of Bornholm, Denmark.

Bagå Formation

The Bagå Formation is a geological formation dating to around 199 to 170 million years ago, in the Early and Late Jurassic. It is located on the island of Bornholm, Denmark.

References

  1. 1 2 3 Bonde, N.; Christiansen, P. (2003). "New dinosaurs from Denmark". Comptes Rendus Palevol. 2: 13. doi:10.1016/S1631-0683(03)00009-5.
  2. 1 2 Milàn, J.; Rasmussen, B.W.; Bonde, N. (2012) "Coprolites with prey remains from coprophagous organisms from the Lower Cretaceous (Late Berriasian) Jydegaard Formation of Bornholm, Denmark". New Mexico Museum of Natural History and Science. Bulletin57: 235-240