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Glossary · Stratigraphy

Formation

The basic unit of lithostratigraphy: a body of rock distinguished by its lithology, mappable at the surface, and named for a place (a type locality).

The basic unit of lithostratigraphy: a body of rock distinguished by its lithology, mappable at the surface, and named for a place (a type locality). A formation is defined by rock type, not by age, and can be diachronous.

Sources

Cite this article

Stratum Strata. "Formation" (Glossary). Stratum Strata pack 2026.09, as of 2026-09-16. https://stratum.black/strata/glossary/formation. Accessed 2026-09-21.

BibTeX · CSL-JSON

@misc{stratum-formation,
  title        = {Formation},
  author       = {{Stratum Strata}},
  howpublished = {\url{https://stratum.black/strata/glossary/formation}},
  year         = {2026},
  note         = {Glossary article, Stratum Strata pack 2026.09, as of 2026-09-16; sources: stratum. Accessed 2026-09-21.}
}

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