Early radioisotopic age constraints on the Campanian formations of the WIB consisted of K–Ar analyses of biotite and feldspar from interbedded bentonites115,116, with assumed uncertainties on the get of ± five%, and these analyses are usually not discussed additional right here. Biotite ages, in particular, are regarded as of questionable https://bookmarkcitizen.com/story13241280/the-fact-about-fossil-record-that-no-one-is-suggesting