Apón Formation

The Apón Formation is a geological formation in northwestern Venezuela (Maracaibo Basin) and northern Colombia (La Guajira),[1] whose thick-bedded limestone interbedded with subordinate amounts of dark gray calcareous shale and sandy shale strata date back to the Early Cretaceous (Late Aptian epoch).[2] Pterosaur remains of Ornithocheiridae indet. (=?Anhangueridae indet.) are among the fossils that have been recovered from the formation.[3]

Apón Formation Stratigraphic range: Early Cretaceous (Late Aptian)
Type	Geological formation
Sub-units	Machiques Member
Underlies	Aguardiente Formation
Overlies	Río Negro Formation
Lithology
Primary	Limestone, marl
Other	Calcareous and sandy shales
Location
Coordinates	10°57′30″N 71°38′50″W
Approximate paleocoordinates	7.7°N 41.1°W
Region	La Guajira, Maracaibo Basin
Country	Colombia  Venezuela
Type section
Named for	Apón River
Apón Formation (Venezuela)

Fossil content

The following fossils, among others, have been found in the Apón Formation at Toas island: Spiroculina sp., Orbitolina concava, Gryphaeostrea, Amphidonte (Ceratostreon) boussingaulti, Ostrea sp., Amphitriscoelus waringi, Requienia sp., Parahoplites sp., Cheloniceras sp., Quinqueloculina sp., Triloculina sp.,[2] and Panopea (Myopsis) plicata in Río Negro.[4]

See also

• List of pterosaur-bearing stratigraphic units

References

1. García González et al., 2010
2. Apón Formation (Toas Island) at Fossilworks.org
3. Barrett et al., 2008, p.84
4. Apón Formation (Río Negro) at Fossilworks.org

Bibliography

• Barrett, P.M.; R.J. Butler; N.P. Edwards, and A.R. Milner. 2008. Pterosaur distribution in time and space: an atlas. pp.61-107. in Flugsaurier: Pterosaur papers in honour of Peter Wellnhofer. Hone, D.W.E., and Buffetaut, E. (eds), 1–264. 28; Zitteliana B. Accessed 2017-03-31.
• García González, Mario; Ricardo Mier Umaña, and Luis Enrique Cruz Guevara. 2010. Reconstrucción de la historia paleotermal de la subcuenca de la Baja Guajira, Colombia. Boletín de Geología 32. . Accessed 2017-03-31.