Meaning of tephrochronology

teph•ro•chro•nol•o•gy

Pronunciation: (tef"rō-kru-nol'u-jē), [key]
— n. Geol.
  1. a geochronologic technique based on the dating of layers of volcanic ash. Cf.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.