The Early Triassic is the first of three epochs of the TriassicPeriod of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic, which is a unit in chronostratigraphy. The Early Triassic is the oldest epoch of the MesozoicEra and is divided into the Induan and Olenekianages.