geologic time
Where the Holocene begins
The epoch we live in has a formally defined base — and the way that boundary is defined says a great deal about how geological time is standardised.
About: Holocene · International Chronostratigraphic Chart
A boundary with a number
On the International Chronostratigraphic Chart (v2024/12), the base of the Holocene — the epoch spanning roughly the last eleven and a half thousand years — is placed at 0.0117 million years before present.[1]
Why the number is not the definition
The chart itself is careful about what defines a unit: numerical ages are subject to ongoing revision and do not define units — physical reference points (GSSPs) do. Lithoen preserves that nuance by recording the age with the chart version it comes from, so a future revision supersedes rather than silently overwrites it.[1]
Bracketed references link to the structured entity records whose claims support each paragraph. Last updated 2026-09-06.