A Cretaceous Time Scale

An emendation of published Cretaceous time scales is proposed on the basis of presently available age data. The standard geochronologic subdivision is combined with a linear numeric scale, biostratigraphic framework, and geomagnetic-reversal time scale. The biostratigraphic framework includes standard Tethyan and boreal pelagic macrofossil zonations and planktonic as well as benthic microfossil zones and biohorizons. Basement ages at some Deep Sea Drilling Project sites are evaluated and related to the geomagnetic-reversal scale.