BOLIVIA           
                             PARAGUAY            BRASIL                                       URUGUAY
    NORTE                                                                       BRASIL                                        URUGUAY
        DE               ARGENTINA        ARGENTINA                                 ARGENTINA
ARGENTINA                                 
___________      ___________       ___________          ______           ___________         _________
                                                 Basaltos de Serra Geral y equivalentes
         Gr.                      Fm.                       Fm.                    Fm.                      Fm.                       Fm.
                                                             Botucatú            Botucatú                                             Rivera
                                                                                
                                                                
                                                                 Fm.             Gr. Rosario                                              Fm.
      Tacurú               Misiones               Piramboia            do Sul              Tacuarembó         Tacuarembó
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                                                                                                                           Fm.  Buena Vista
                                                                                                                 
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