undifferentiated rock units

Paleontology and geology

Throughout the Carboniferous, mainland Nunavut was above sea level and covered with forests and swamps of cycads, conifers, seed ferns, and gnetophytes. Pollen and spores from these plants were carried out to the seas that covered the northern part of the territory. In the Early Carboniferous, mountain-building continued as a continental collision in the north folded, faulted, and pushed up rocks. By the Middle Carboniferous, the collision ended and a basin developed over some of the islands. As the basin got deeper over time, shallow coastal evaporites, sandstones, and limestones gave way to deeper water shales. Bryozoans, brachiopods, and crinoids lived in these waters, and their fossils are found in some small exposures of rocks from this period. Some Carboniferous rocks may be included in the undifferentiated Paleozoic rocks on this map, and they may appear on other more detailed maps.