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LITHOEN

Geological time unit

Paleogene

The first period of the Cenozoic, beginning at the boundary that closes the Mesozoic and comprising the Paleocene, Eocene and Oligocene epochs.

Classification

rank
period

How this record is known

1
Settled consensus
Cited as the accepted position of the discipline.

1 of 1 claims on this page cite at least one registered source. Counts describe how each statement is known, not how likely it is to be true.

What Lithoen records

Each claim states how it is known and cites its evidence.

Established66–23.04 Ma before present

On the International Chronostratigraphic Chart (v2024/12), the Paleogene spans 66.0 to 23.04 million years before present.

Not stated verbatim by the source — derived: base of the unit x base of the next younger unit -> span

A span is not stated anywhere on the chart: the chart gives boundary ages, and the span between two of them is composed from the two lines the premises cite.

  • definition basis: International Chronostratigraphic Chart v2024/12; the chronostratigraphic counterpart of the Paleogene is the Paleogene System.
  • precision note: The chart states that numerical ages are subject to ongoing revision and do not define units; GSSPs do.

Evidence support: Derived from the cited evidence one source

Evidence: Cohen 2024 Primary authority

In the knowledge graph

Record last updated 2026-09-06. Corrections follow the published corrections policy; superseded claims are retained, never silently edited.