The Gamoneda Formation is an Emsian geologic

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondar ...

of southern Bolivia. The approximately thick formation comprises marine

mica Micas ( ) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into extremely thin elastic plates. This characteristic is described as perfect basal cleavage. Mica is ...

ceous grey

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, p ...

s and burrowed grey sandstones and

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especial ...

s.Scaphiocoelia Zone trilobites, Gamoneda Fm
at

Fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...

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Fossil content

The formation has provided the following fossils: * '' Acastoides gamonedensis'' * '' Australocoelia palmata'' * '' Australospirifer hawkinsi'' * '' Australostrophia mesembria'' * '' Bainella (Belenops) insolita'' * '' Cryptonella baini'' * '' Deltacephalaspis (Deltacephalaspis) comis'' * '' Deltacephalaspis (Deltacephalaspis) retrospina'' * '' Deltacephalaspis (Prestalia) tumida'' * '' Derbyina jamesiana'' * '' Gamonedaspis scutata'' * '' Kozlowskiaspis (Romanops) australis'' * '' Notiochonetes falklandica'' * '' Phacopina convexa'' * '' Plicoplasia planoconvexa'' * '' Protoleptostrophia concinna'' * '' Pustulatia curupira'' * '' Schizostylus (Curuyella) granulata'' * '' Tarijactinoides jarcasensis'' * '' Burmeisteria sp.'' * '' cf. Francovichia sp.'' * Calmoniidae indet. * Eurypterida indet.

References

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Fossil content

See also

References

Further reading