Tubul Formation (Spanish: Formación Tubul) is an Early Pleistocene (formerly described as Middle Pliocene in 1968 and Late Pliocene in 1976)[1] sedimentary formation located in Arauco Province in south–central Chile. Its sediments were deposited in marine conditions. It overlies unconformably the folded sedimentary formations of Ranquil (Miocene–Pliocene), Quiriquina (Late Cretaceous) and the Lebu Group (Paleocene-Eocene).[2]

Tubul Formation
Stratigraphic range: Early Pleistocene
TypeGeological formation
UnderliesQuaternary sediments
OverliesRanquil Formation
Thickness>100 m (330 ft)
Lithology
PrimaryClay-rich sandstone and silt
Location
Coordinates37°48′S 73°18′W / 37.8°S 73.3°W / -37.8; -73.3
Approximate paleocoordinates37°54′S 72°48′W / 37.9°S 72.8°W / -37.9; -72.8
RegionBío Bío Region
Country Chile
Type section
Named forCaleta Tubul
Named byEgidio Feruglio
Year defined1949
Tubul Formation is located in Chile
Tubul Formation
Tubul Formation (Chile)

Mollusc fossils found in the formation derives from soft-bed environments (contrary to rocky coasts). Evidence from the fossil mollusc fauna of the Tubul Formation seem to indicate that local water temperatures were lower in the Pliocene than today. Waters and mollusc faunas of Magallanes Region are modern-day equivalents of Tubul Formation.[3]

The formation was first defined by Egidio Feruglio in 1949.[3]

See also

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References

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  1. ^ Las Peñas (Tubul Fm) at Fossilworks.org
  2. ^ García A., Floreal (1968). Ceccioni, Giovanni (ed.). El Terciario de Chile Zona Central (in Spanish). Santiago de Chile: Ediorial Andrés Bello. pp. 25–57.
  3. ^ a b Valdovinos, Claudio; Nielsen, Sven N. (2006). "Mollusks of the Tubul Formation (South-Central Chile): Implications for the Early Pleistocene climate of the Southeastern Pacific" (PDF). XI Congreso Geológico Chileno. Vol. II. pp. 135–138. Archived from the original (PDF) on August 18, 2016.

Further reading

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  • S. N. Nielson and C. Valdovinos. 2008. Early Pleistocene mollusks of the Tubul Formation, south-central Chile. The Nautilus 122(4):201-216