The Boundary Between Two Chronostratigraphic Units, for Example, Ordovician and Silurian

question 15

Multiple Choice

The boundary between two chronostratigraphic units, for example, Ordovician and Silurian, is formally defined at a single locality known as a

• A) stratigraphic range.
• B) geochronologic unit.
• C) boundary stratotype.
• D) time-rock unit.

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