The Forbes Shale is a

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

in the

Sacramento Valley , photo =Sacramento Riverfront.jpg , photo_caption= Sacramento , map_image=Map california central valley.jpg , map_caption= The Central Valley of California , location = California, United States , coordinates = , boundaries = Sierra Nevada (ea ...

of northern

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. It is found in the

Sutter Buttes The Sutter Buttes (Maidu: ''Histum Yani'' or ''Esto Yamani'', Wintun: ''Olonai-Tol'', Nisenan: ''Estom Yanim'') are a small circular complex of eroded volcanic lava domes which rise as buttes above the flat plains of the Sacramento Valley in Sut ...

area of

Sutter County, California Sutter County is a county located in the U.S. state of California. As of the 2020 census, the population was 99,633. The county seat is Yuba City. Sutter County is included in the Yuba City, CA Metropolitan Statistical Area as well as the Sacra ...

. It preserves

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...

dating back to the

Coniacian The Coniacian is an age or stage in the geologic timescale. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series and spans the time between 89.8 ± 1 Ma and 86.3 ± 0.7 Ma (million years ago). The Coniacian is preceded by t ...

stage of the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (or rhetorical period), a concept ...

.Forbes Shale
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 ...

.org

Fossil content

The following fossils were reported from the formation:Anderson, 1958 ;Bivalves * ''

Cladoceramus undulatoplicatus ''Cladoceramus'' is an extinct genus of fossil Marine (ocean), marine pteriomorphian bivalves that superficially resembled the related winged pearly oysters of the Extant taxon, extant genus ''Pteria (bivalve), Pteria''. They lived in the Santoni ...

'' * ''Glycymerita veatchii'' * '' Inoceramus subundatus'' * '' I. Inoceramus vancouverensis'' * '' I. aff. chicoensis'' * '' I. aff. klamathensis'' * '' I. aff. whitneyi'' * ''Parallelodon, Parallelodon (Nanonavis) brewerlanus'' * '' Pseudomelania colusaensis'' ;Gastropods * '' Bernaya (Protocypraea) kayei'' * ''Biplica obliqua'' * '' Dentalium (Entalis) whiteavesi'' * '' Pseudomelania colusaensis'' * '' Tessarolax distorta'' * ''Volutoderma californica'' ;Ammonites * '' Baculites chicoensis'' * '' B. inornatus'' * '' Desmophyllites diphylloides'' * '' Eupachydiscus arbucklensis'' * '' E. willgreeni'' * ''

Eutrephoceras campbelli ''Eutrephoceras'' is an extinct genus of nautilus from the Late Jurassic to the Miocene (around 161 to 5 million years ago). They are characterized by a highly rounded involute shell with slightly sinuous suture patterns. Description ''Eutrep ...

'' * '' Lytoceras (Gaudryceras) alamedense'' * ''Nowakites dobbinsi'' * ''N. rumseyensis'' * ''Oxybeloceras petrolense'' * ''Parapachydiscus cortinaensis'' * '' Puzosia (Holcodiscoides) gorrilli'' * '' Puzosia (Parapuzosia) arenaica'' * '' Baculites sp.'' * ''Canadoceras sp.'' * '' Hauericeras sp.''

References

Bibliography

* {{cite LSA , last=Anderson , first=F. M , year=1958 , title=Upper Cretaceous of the Pacific Coast , journal=Geological Society of America Memoir , volume=71 , pages=1–378

Fossil content

See also

References

Bibliography

Further reading