undifferentiated rock units

Paleontology and geology

Through the Triassic, most of Nunavut was above sea level. Forests of ferns, seed ferns, conifers, cycads, and cycadeoids covered the land. Pollen and spores from these plants, as well as sediment eroding from the land, traveled down rivers, through deltas, and out into a basin that covered several Arctic islands. The shallow to deep waters of the basin were home to crinoids, brachiopods, bivalves, and other invertebrates that left their traces in the sand. While some of the sandstones, shales, limestones, and coals from this period have been eroded away or buried under younger rocks, a few exposures can be found in the northern islands.