geologic timescale, Berriasian is a stage of the Early Cretaceousepoch, and the first of the entire Cretaceousperiod. It spanned between 145.5 ± 4.0 Ma and 140.2 ± 3.0 Ma (million years ago). The Berriasian stage succeeds the Tithonianstage of the Late Jurassicepoch and precedes the Valanginianstage of the Early Cretaceous epoch.
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