Ameki Formation

Last updated
Ameki Formation
Stratigraphic range: Lutetian-Bartonian
Type Geological formation
Unit of Bende-Ameki Group
Lithology
Primary Shale
Other Sandstone, siltstone
Location
Coordinates 6°00′N7°00′E / 6.0°N 7.0°E / 6.0; 7.0
Approximate paleocoordinates 1°36′N1°30′E / 1.6°N 1.5°E / 1.6; 1.5
CountryFlag of Nigeria.svg  Nigeria
Extent Niger Delta Basin
Type section
Named for Ameki
Nigeria relief location map.jpg
Orange pog.svg
Ameki Formation (Nigeria)

The Ameki Formation is a Lutetian to Bartonian geological formation located in Nigeria. It belongs to the Bende-Ameki Group, which also consists of two formations namely Nanka Formation, Nsugbe Formation. [1] [2]

Contents

Fossil content

Among others, the following fossils have been reported in the formation: [3] [4]

Mammals

Mammals reported from the Ameki Formation
GenusSpeciesPresenceMaterialNotesImages
Pappocetus P. lugardiOmbialla District. [5] Mandibles. [5] [6] A protocetid.

Reptiles

Birds

Birds reported from the Ameki Formation
GenusSpeciesPresenceMaterialNotesImages
Gigantornis G. eaglesomeiA pelagornithid.

Squamates

Squamates reported from the Ameki Formation
GenusSpeciesPresenceMaterialNotesImages
Pterosphenus Trunk vertebra. [7] A palaeophiid.

Turtles

Turtles reported from the Ameki Formation
GenusSpeciesPresenceMaterialNotesImages
Cosmochelys C. dolloiOmbialla District. [5] Portions of carapace. [5] A dermochelyid.

Invertebrates

Cephalopods

Cephalopods reported from the Ameki Formation
GenusSpeciesPresenceMaterialNotesImages
Deltoidonautilus D. nwajideiMultiple specimens. [2] A nautiloid.

See also

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References

  1. Ogbe, Ovie B.; Osokpor, Jerry (2021-01-01). "Depositional facies, sequence stratigraphy and reservoir potential of the Eocene Nanka Formation of the Ameki Group in Agu-Awka and Umunya, southeast Nigeria". Heliyon. 7 (1): e05846. Bibcode:2021Heliy...705846O. doi: 10.1016/j.heliyon.2020.e05846 . ISSN   2405-8440. PMC   7820494 . PMID   33521344.
  2. 1 2 Odumodu, Chukwuemeka; Nfor, Bruno (January 2012). "A New Paratype of an Eocene Nautiloid From the Ameki Formation, Southeastern Nigeria: Implications for Age and Paleoenvironmental Interpretation". Stratigraphy and Sedimentology of Oil-Gas Basins.
  3. Ameki at Fossilworks.org
  4. Port Harcourt at Fossilworks.org
  5. 1 2 3 4 Andrews, C. W. (December 1919). "A Description of New Species of Zeuglodont and of Leathery Turtle from the Eocene of Southern Nigeria". Proceedings of the Zoological Society of London. 89 (3–4): 309–319. doi:10.1111/j.1096-3642.1919.tb02124.x. ISSN   0370-2774.
  6. McLeod, Samuel A.; Barnes, Lawrence G. (January 1996). "The Systematic Position of Pappocetus Lugardi and a New Taxon From North America (Archaeoceti: Protocetidae)". The Paleontological Society Special Publications. 8: 270. doi: 10.1017/S2475262200002720 . ISSN   2475-2622.
  7. Georgalis, Georgios L. (2023-06-19). "First potential occurrence of the large aquatic snake Pterosphenus (Serpentes, Palaeophiidae) from Nigeria, with further documentation of Pterosphenus schweinfurthi from Egypt". Alcheringa: An Australasian Journal of Palaeontology. 47 (3): 327–335. Bibcode:2023Alch...47..327G. doi:10.1080/03115518.2023.2217874. ISSN   0311-5518. S2CID   259422068.

Further reading