High spatial resolution U-Pb geochronology and Pb isotope geochemistry of magnetite-apatite ore from the Pea Ridge iron oxide-apatite deposit, St. Francois Mountains, southeast Missouri, USA - Neymark, Leonid A.; Holm-Denoma, Christopher; Pietruszka, Aaron; Aleinikoff, John; Fanning, C.; Pillers, Renee; Moscati, Richard (Economic Geology, 2016)