Dos Bocas Formation

Dos Bocas Formation Stratigraphic range: Chattian (Deseadan) ~26–24 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of
Underlies
Overlies
Lithology
Primary	Sandstone
Location
Coordinates	1°48′S 80°48′W / 1.8°S 80.8°W / -1.8; -80.8Coordinates: 1°48′S 80°48′W / 1.8°S 80.8°W / -1.8; -80.8
Approximate paleocoordinates	3°36′S 75°30′W / 3.6°S 75.5°W / -3.6; -75.5
Region	Santa Elena Province
Country	Ecuador
Extent
Dos Bocas Formation (Ecuador)

The Dos Bocas Formation is a Chattian, about 26 to 24 Ma,^[1] (Deseadan in the SALMA classification) geologic formation of the in southwestern Ecuador.

Description[]

The formation comprises moderately-sorted, fine to medium sandstones with angular quartz-feldspathic clasts. Conspicuous rounded green grains are probably glauconite, but berthierine cannot be dismissed. The matrix is micritic and volcanogenic, possibly bentonitic. The formation was deposited in an estuarine to mid shelf environment. Fossils of sharks, turtles and the tropical Urkudelphis were recovered from the formation.^[1]

Fossil content[]

The formation has provided fossils of:

• Carcharocles angustidens
• Urkudelphis chawpipacha^[2]
• Chelonioidea indet.

See also[]

• List of fossiliferous stratigraphic units in Ecuador

References[]

Bibliography[]

• Tanaka, Y; J. Abella; Gl Aguirre Fernández; M. Gregori, and R.E. Fordyce. 2017. A new tropical Oligocene dolphin from Montañita/Olón, Santa Elena, Ecuador. PLoS One 12. e0188380. Accessed 2019-02-09.

Further reading[]

• Lorenzo, Erica; Wladimir Andrés Roca Beltrán; Manuel Martínez; Antonio Morato; Paulo César Escandón Panchana, and Cristian Paul Álvarez Domínguez. 2018. Correlación geoquímica entre crudos y rocas del sistema petrolero de la península de Santa Elena y el golfo de Guayaquil. Boletín de Geología 40. 31–42. Accessed 2018-10-01.