stratigraphic intervals
   (System) †Cretaceous (145.0 - 66.0 Ma)
     (Series) †Lower (145.0 - 100.5 Ma)
       1 (Stage) †Albian (113.0 - 100.5 Ma)
       2 (Stage) †Aptian (125.0 - 113.0 Ma)
       3 (Stage) †Barremian (129.4 - 125.0 Ma)
       4 (Subseries) †Neocomian