Tor Formation

{{Short description|Geological formation of Danian (lowermost Paleocene) age}}

{{Infobox rockunit

| name = Tor Formation

| period = Maastrichtian

| age = Late Cretaceous Late {{fossilrange|Campanian|Maastrichtian}}

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| type = Geological formation

| prilithology = Chalk

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| unitof = Chalk Group

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| underlies = Ekofisk Formation

| overlies = Hod Formation

| thickness = up to {{Convert|472|m|ft|-1}}

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| region = North Sea

| country = Denmark, Norway & United Kingdom

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| namedfor = Tor field

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| location_ts = Well 1/3-1. Norwegian sector

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The Tor Formation is a geological formation of late Campanian to Maastrichtian (uppermost Cretaceous) age. It forms the part of the Chalk Group in the North Sea. It is an important reservoir for oil and gas in fields such as Valhall. It overlies the Hod Formation. It underlies the Ekofisk Formation with local evidence of unconformity.{{Cite web |last=NPD |title=Tor Formation |url=https://nhm2.uio.no/norges/litho/tor.php |website=NORLEX|access-date=25 August 2022 }}{{Cite web |last=British Geological Survey |title=Tor Formation |url=https://webapps.bgs.ac.uk/lexicon/lexicon.cfm?pub=TOR |access-date=26 August 2022 |website=The BGS Lexicon of Named Rock Units}}{{Cite journal |last=Blinkenberg |first=K.H. |last2=Anderskouv |first2=K. |last3=Sheldon |first3=E. |last4=Bjerrum |first4=C.J. |last5=Stemmerik |first5=L. |date=2020 |title=Stratigraphically controlled silicification in Danian chalk and its implications for reservoir properties, southern Danish Central Graben |journal=Marine and Petroleum Geology |volume=115 |doi=10.1016/j.marpetgeo.2019.104134}}