The Canadian, either as a series or as an Epoch is the name that has been given to the Lower, or Early, Ordovician in North America and has been applied worldwide.
Rocks of Cassinian age are found in the Champlain Valley and among other places in North America in the Great Basin of Western Utah and Nevada, and in the uppermost El Paso Group in southern New Mexico and west Texas.
[3] which may be short, looking at the El Paso section and Early Ordovician cephalopod evolution [1][4] In worldwide terms the Cassinian is upper, or late Arenigian which is exactly equivalent to the newly proposed Floian, both spanning the same 6.8 million years.
However the Ibexian, named for the Ibex region in western Utah, extends 2.7 .m.y.
[3] The Cassinian is followed in North America by the Whiterockian and by the newer ICS Dapingian, given respective durations of 9.8 and 3.7 m.y.