Category:Volcanism by geochronology


 * Volcanism grouped or listed by geochronology — when they were active. Volcanoes have been erupting in some form throughout Earth's history.


 * 1) Tertiary and Quaternary used to be considered the two periods of the Cenozoic in their own right, but this is no longer formal. Some split the large Tertiary into the lower Paleogene and established the Neogene to include the last two epochs (Miocene and Pliocene) of the Tertiary.  Some include both epochs of the Quaternary in the Neogene as well, while others consider the Quaternary to be the period after the Neogene.  As of 2006 the disagreement remains.  See Neogene for details.
 * 2) Pre-Holocene is a broad and vague term for all time before the Holocene epoch today.
 * 3) Precambrian originated as the vague term for all time before the Cambrian period. As this time became better understood, the Hadean, Archean and Proterozoic eons were established and the Precambrian elevated to a "supereon" before today's Phanerozoic.  However, "supereon" in terrestrial time refers almost exclusively to Precambrian time.