Fig. S4: Biotite Mg/Mg+Fe+Mn vs Mn diagram of P2 ash layers. Chemical and petrographic fingerprinting of volcanic ashes as a tool for high-resolution stratigraphy of the upper Miocene Pisco Formation (Peru) BosioGiulia GioncadaAnna MalinvernoElisa Di CelmaClaudio VillaIgor M. CataldiGiuseppe GariboldiKaren CollaretaAlberto UrbinaMario BianucciGiovanni 2018 Fig. S4: Biotite Mg/Mg+Fe+Mn vs Mn diagram of P2 ash layers.