Roca Formation  search
RTArgentina
 Council Grove Group
 Danian
 K-T boundary
 Kansas
 Maestrichtian
 Nebraska
 Oklahoma
 Wolfcampian
SNK-T age (Maestrichtian-Danian) or Paleocene of Argentina. Also a Wolfcampian member of the Council Grove Group in NE Kansas, SE Nebraska, and N Oklahoma. Indexed with age or ages as applicable.