The river cut through a series of rises then plateaux forming wide plains covered with shells and shingle, and Darwin discussed with FitzRoy his interpretation that these terraces had been shores that had gradually raised in accordance with Lyell's theories.
O río cortaba unha serie de elevacións e despois mesetas que formaban amplas chairas cubertas de cunchas e croios, e Darwin discutiu con FitzRoy a súa interpretación que estas terrazas foran ribeiras que se elevaran gradualmente de acordo coas teorías de Lyell.