Sella Formation

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Sella Formation
Stratigraphic range: Dapingian-Darriwilian
~478–450  Ma
Type Geological formation
Lithology
Primary Siltstone, sandstone
Other Shale, limestone, coquina
Location
Coordinates 21°24′S64°36′W / 21.4°S 64.6°W / -21.4; -64.6 Coordinates: 21°24′S64°36′W / 21.4°S 64.6°W / -21.4; -64.6
Approximate paleocoordinates 42°48′S131°36′W / 42.8°S 131.6°W / -42.8; -131.6
Region Tarija Department
CountryBolivia
Bolivia physical map.svg
Dark Green 004040 pog.svg
Dark Green 004040 pog.svg
Sella Formation (Bolivia)

The Sella Formation is a Dapingian to Darriwilian geologic formation of southern Bolivia. The grey to green bioturbated siltstones interbedded with thin sandstone layers bear lenticular shell beds. Other parts of the formation contain yellow-green limy shales and grey sandy limestones. Coquinas often fill gutter casts and included brachiopods, trilobites, bivalves and nautiloids. The sediments were deposited in an open marine environment. [1] [2] [3] [4] [5] The species Coxiconchia sellaensis was named after the formation.

Contents

Fossil content

The formation has provided the following fossils:

See also

Related Research Articles

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