Cosmogenic 14C in carbonate rocks

The rate of in situ production of cosmogenic 14CO in limestone is 18±3 atom/g-CaCO3/year corrected to high latitude and sea level, based on measurements of 14CO in limestone associated with the Bonneville–Provo shoreline complex in Utah. In situ cosmogenic 14CO was separated cryogenically from CO2 using 14C−`deadʹ CO as a carrier for in situ cosmogenic 14CO. This rate of production was used to estimate an age of 4360±1220 cal. year B.P. for the last movement on the South Oquirrh Mountain Fault Zone in northern Utah, and an age of at least 10,600±900 years for the penultimate event of the Pleasant Valley fault in northern Nevada.