During the Paleozoic, eustatic transgressions and regressions of sea level resulted in
the formation of Epeiric seas. This was also the case in North America,
known as Laurentia at the time. The Ottawa area was covered by the
Epeiric seas and this resulted in the sedimentary formations visible
today. According to the theory of continental drift and plate tectonics,
Laurentia was equatorial during the Cambrian to Ordovician.
The environment generated in the Ottawa area during the Ordovician
caused habitats that only certain organisms could survive. The paleoclimate of the Ottawa area
consisted of shallow, warm, somewhat saline waters that were excellent conditions for some creatures and detrimental for
others. The many organisms that could survive the environment included the
phylum Arthropoda, specifically the class Trilobita, and the phylum
Brachiopoda, specifically the classes Inarticulata and Articulata.
consists of Precambrian basement rocks that are overlain by Ordovician sediment. Several formations occurred during this time. The
here was variation in the distribution of the organisms in different stratigraphic layers.