Stratotype

In geology, a stratotype or type section is the physical location or outcrop of a particular reference exposure of a stratigraphic sequence or stratigraphic boundary.

If the stratigraphic unit is layered, it is called a stratotype, whereas the standard of reference for unlayered rocks is the type locality.

[1] Also it can be defined as "The particular sequence of strata chosen as standard of reference of a layered stratigraphic unit.

"[This quote needs a citation] When a stratigraphic unit is nowhere fully exposed, the original type section may be supplemented with reference sections covering the full thickness of the unit.

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