Paleontology and geology

In the Early Silurian, warm, tropical seas continued to cover the southern half of Saskatchewan, while the northern part was exposed to erosion. Over time, the seas drained away, and by the Late Silurian, only the southern edge of the province was covered by very shallow waters. Most of the rocks from this period are buried far below the surface under younger rocks, but a few exposures can be found in the east. These mudstones and dolostones, some of which contain stromatolite fossils, were deposited in lagoons and mudflats near the coastline.