"The Permian section exposed at Apillapampa is divided into two formations: the Yaurichambi sandstone (92 feet) and the overlying Copacabana formation (850 feet). The Copacabana formation is itself divided into (1) a basal limestone member (574 feet) carrying abundant megafossils and fusulinids that permit a more concise age determination than was previously possible and (2) a coal member (276 feet) which also carriesfossil plants. Both members of the Copacabana formation are assigned a Wolfcampian-Leonardian age based on abundant fusulinid data."