Tertiary 4 : Period of geologic time from about 65 million years ago until 1.8 million years ago. It contains the Paleocene, Eocene, Oligocene, Miocene, and Pliocene epochs. (GSA 1999 Geologic Timescale)
U.S. Department of the Interior, U.S. Geological Survey, US Geological Society (USGS), Glossary of Volcano and Related Terminology, USGS/Cascades Volcano Observatory, Vancouver, Washington, USA 2006. http://vulcan.wr.usgs.gov/Glossary/volcano_termino logy.html, (ND/ Volc Sci - Amer) {493}