An Evaluation of Uranium-Series Dating of Fossil Echinoids from Southern California Pleistocene Marine Terraces

Authors

Daniel R. Muhs, U.S. Geological SurveyFollow
Los Angeles County Museum of Natural History, Los Angeles, CA, Los Angeles County Museum of Natural History, Los Angeles, CA

Date of this Version

1985

Citation

Mulls, D.R. and Kennedy, G.L., 1985. An evaluation of uranium-series dating of fossil echinoids from southern California Pleistocene marine terraces. Mar. Geol., 69: 187-- 193.

Comments

U.S. government work

Abstract

Fossil sea urchins (Strongylocentrotus) from Pleistocene marine terraces on the southern California Channel Islands have been dated by the uranium-series method in order to test the suitability of echinoids for dating marine terraces. Results indicate that urchin plates and spines do not behave as closed systems with respect to both uranium and thorium. Calculated ages based on these data do not agree with uranium-series ages (120,000 and 127,000 yrs) obtained previously from corals from the same localities. Thus, fossil sea urchins (Strongylocentrotus) are not considered suitable for uranium-series dating of Pleistocene marine terrace deposits.