Manley, K., Mehnert, H.H. (1981). New K-Ar ages for Miocene and Pliocene volcanic rocks in the northwestern Espanola Basin and their relationships to the history of the Rio Grande Rif. Isochron/West Bulletin of Isotopic Geochronology, vol. 30, p. 5-8. Edited by: Schilling, John H. Keywords: Miocene, Pliocene Espanola Basin, Rio Grande Rift, northcentral NM