Geologic time: The age of the Earth

Abstract

Sample, recovered from bed of ash near Crater Lake, Oregon, is from a tree burned in the violent eruption of Mount Mazama which created Crater Lake. This eruption blanketed several States with ash, providing geologists with an excellent time zone. Charcoal. _____________________ _______ _______ ___ ___-__-_ _10,130 Sample collected from the "Marmes Man" site in southeastern Washington. This rock shelter is believed to be among the oldest known inhabited sites in North America.

The Geologic Story of Colorado National Monument

“…Of most concern to this report, the boundary between the Pliocene and Pleistocene Epochs has been changed from 3 million to 2 million years. Drawn by John R. Stacy originally for inclusion in a report by Newman (1976). (Fig.…”