Editing North Sea (section)

== Geology ==
{{main|Geology of the North Sea|Geology of southern North Sea}}

Shallow [[epicontinental]] seas like the current North Sea have since long existed on the European [[continental shelf]]. The [[rift]]ing that formed the northern part of the Atlantic Ocean during the [[Jurassic]] and [[Cretaceous]] periods, from about {{ma|150}}, caused [[tectonic uplift]] in the British Isles.<ref name="Ziegler">{{cite journal
|last = Ziegler
|first = P. A.
|title =Geologic Evolution of North Sea and Its Tectonic Framework
|journal=AAPG Bulletin|volume =59 |year=1975
|doi = 10.1306/83D91F2E-16C7-11D7-8645000102C1865D }}
</ref> Since then, a shallow sea has almost continuously existed between the uplands of the [[Fennoscandian Shield]] and the British Isles.<ref>See Ziegler (1990) or Glennie (1998) for the development of the paleogeography around the North Sea area from the Jurassic onwards</ref> This precursor of the current North Sea has grown and shrunk with the rise and fall of the [[eustacy|eustatic]] sea level during geologic time. Sometimes it was connected with other shallow seas, such as the sea above the [[Seine|Paris Basin]] to the south-west, the [[Paratethys|Paratethys Sea]] to the south-east, or the [[Tethys Ocean]] to the south.<ref name="Torsvik">{{cite web
 |last         = Torsvik
 |first        = Trond H.
 |author2      = Daniel Carlos
 |author3      = Jon L. Mosar
 |author4      = Robin M. Cocks
 |author5      = Tarjei N. Malme
 |title        = Global reconstructions and North Atlantic paleogeography 440 Ma to Recen
 |date         = November 2004
 |url          = http://www.earthdynamics.org/torsvik/torsvik-papers/2002/2002-Torsvik-etal-BATLAS.pdf
 |access-date  = 19 November 2008
 |archive-date = 22 June 2015
 |archive-url  = https://web.archive.org/web/20150622010928/http://www.earthdynamics.org/torsvik/torsvik-papers/2002/2002-Torsvik-etal-BATLAS.pdf
 |url-status   = live
}}</ref>

During the Late Cretaceous, about {{ma|85}}, all of modern mainland Europe except for Scandinavia was a scattering of islands.<ref name="Glennie"/> By the Early [[Oligocene]], {{ma|34|28}}, the emergence of Western and Central Europe had almost completely separated the North Sea from the Tethys Ocean, which gradually shrank to become the Mediterranean as Southern Europe and South West Asia became dry land.<ref>{{cite book
 |last         = Smith
 |first        = A. G.
 |title        = Atlas of Mesozoic and Cenozoic Coastlines
 |publisher    = Cambridge University Press
 |year         = 2004
 |isbn         = 978-0-521-60287-7
 |pages        = 27–38
 |url          = https://books.google.com/books?id=ZSuuvlMuQaEC&pg=PA66
 |access-date  = 1 July 2020
 |archive-date = 17 April 2023
 |archive-url  = https://web.archive.org/web/20230417083625/https://books.google.com/books?id=ZSuuvlMuQaEC&pg=PA66
 |url-status   = live
 }}</ref> The North Sea was cut off from the English Channel by a narrow [[land bridge]] until that was breached by at least two catastrophic floods between 450,000 and 180,000 years ago.<ref>{{cite journal
|last=Gibbard |first= P.|s2cid= 4400105| title=Palaeogeography: Europe cut adrift
|journal=Nature | volume=448| pages=259–60| date=19 July 2007 | doi=10.1038/448259a
|pmid=17637645
|issue=7151
|bibcode = 2007Natur.448..259G |doi-access=free}} (Registration is required)</ref><ref>{{Cite journal
|last1=Gupta
|first1=Sanjeev
|last2=Collier
|first2=Jenny S.
|last3=Palmer-Felgate
|first3=Andy
|last4=Potter
|first4=Graeme
|s2cid=4408290
|title=Catastrophic flooding origin of shelf valley systems in the English Channel
|journal=Nature
|volume=448
|year=2007
|pages=342–5
|doi=10.1038/nature06018
|pmid=17637667
|issue=7151
|bibcode=2007Natur.448..342G
}}</ref> Since the start of the [[Quaternary]] period about {{ma|2.6}}, the eustatic sea level has fallen during each glacial period and then risen again. Every time the [[ice sheet]] reached its greatest extent, the North Sea became almost completely dry, the dry landmass being known as [[Doggerland]], whose northern regions were themselves known to have been glaciated.<ref>{{cite journal |last1=Bradwell |first1=Tom |last2=Stoker |first2=Martyn S. |last3=Golledge |first3=Nicholas R. |last4=Wilson |first4=Christian K. |last5=Merritt |first5=Jon W. |last6=Long |first6=David |last7=Everest |first7=Jeremy D. |last8=Hestvik |first8=Ole B. |last9=Stevenson |first9=Alan G. |last10=Hubbard |first10=Alun L. |last11=Finlayson |first11=Andrew G. |last12=Mathers |first12=Hannah E. |date=June 2008 |title=The northern sector of the last British Ice Sheet: Maximum extent and demise |url=https://www.sciencedirect.com/science/article/abs/pii/S0012825208000160 |journal=[[Earth-Science Reviews]] |volume=8 |issue=3–4 |pages=207–226 |doi=10.1016/j.earscirev.2008.01.008 |bibcode=2008ESRv...88..207B |s2cid=129790365 |access-date=25 November 2022 |archive-date=25 November 2022 |archive-url=https://web.archive.org/web/20221125175719/https://www.sciencedirect.com/science/article/abs/pii/S0012825208000160 |url-status=live }}</ref> The present-day coastline formed after the [[Last Glacial Maximum]] when the sea began to flood the European continental shelf.<ref name="Plant">{{cite book
|last = Sola
|first = M. A.
|author2 = D. Worsley
|author3 = Muʼassasah al-Waṭanīyah lil-Nafṭ
|title = Geological Exploration in Murzuq Basin
|series = A contribution to IUGS/IAGC Global Geochemical Baselines
|publisher = Elsevier Science B.V.
|year = 2000
|isbn = 9780080532462
|url = https://books.google.com/books?id=WX2iJQmKTvcC&pg=PA18
|access-date = 17 February 2020
|archive-date = 17 April 2023
|archive-url = https://web.archive.org/web/20230417083626/https://books.google.com/books?id=WX2iJQmKTvcC&pg=PA18
|url-status = live
}}</ref>

In 2006 a bone fragment was found while drilling for oil in the North Sea. Analysis indicated that it was a [[Plateosaurus]] from 199 to 216&nbsp;million years ago. This was the deepest dinosaur fossil ever found and the first find for Norway.<ref>{{cite web |url=http://palaeosbios.blogspot.co.uk/2006/04/dinosaur-of-deep.html |title=Dinosaur of the Deep |author=Lindsey, Kyle |date=25 April 2006 |work=Paleontology Blog |access-date=23 June 2013 |archive-date=2 May 2014 |archive-url=https://web.archive.org/web/20140502194031/http://palaeosbios.blogspot.co.uk/2006/04/dinosaur-of-deep.html |url-status=live }}</ref>

<gallery widths="200px" heights="200px">
File:Doggerland.svg|Map showing hypothetical extent of [[Doggerland]] (c. 8,000 BC), which provided a land bridge between Great Britain and continental Europe
File:North Sea -.jpg|North Sea from De Koog, Texel island
File:Mediterranean Rupelian.jpg|The North Sea between {{ma|34}} and {{ma|28}}, as Central Europe became dry land
</gallery>