Ekofisk Formation

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Ekofisk Formation
Stratigraphic range: Danian
O
S
D
C
P
T
J
K
Pg
N
Type Geological formation
Unit of Chalk Group
Underlies Våle Formation
Overlies Tor Formation
Thicknessup to 150 metres (490 ft)
Lithology
Primary Chalk
Other Marl
Location
Region North Sea
Country Denmark, Netherlands, Norway & United Kingdom
Type section
Named for Ekofisk field
LocationWell 2/4-5. Norwegian sector

The Ekofisk Formation is a geological formation of Danian (lowermost Paleocene) age. It forms the uppermost part of the Chalk Group in the North Sea. It is an important reservoir for oil and gas in fields such as Ekofisk. It overlies the Maastrichtian Tor Formation with local evidence of unconformity. It underlies the Våle Formation. [1] [2] [3] [4]

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References

  1. NPD. "Ekofisk Fm". Norwegian Petroleum Directorate Fact Pages. Retrieved 25 August 2022.
  2. British Geological Survey. "Ekofisk Formation". The BGS Lexicon of Named Rock Units. Retrieved 26 August 2022.
  3. DINOloket. "Ekofisk Formation". Stratigraphic nomenclature. Retrieved 26 August 2022.
  4. Blinkenberg, K.H.; Anderskouv, K.; Sheldon, E.; Bjerrum, C.J.; Stemmerik, L. (2020). "Stratigraphically controlled silicification in Danian chalk and its implications for reservoir properties, southern Danish Central Graben". Marine and Petroleum Geology. 115. doi:10.1016/j.marpetgeo.2019.104134.