Type Formation Country Canada, United States Year defined 1939 Overlies Shadow Lake Formation Regions Ontario, New York | Other Shale, sandstone Named by V. J. Okulitch Named for Gull River Underlies Bobcaygeon Formation Primary Limestone, Dolostone | |
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Unit of Simcoe Group
Black River Group | ||
The Gull River Formation is a geological formation of Middle Ordovician age (Caradoc Stage), which outcrops in Ontario, Canada. Lithologically, the formation is dominated by light grey to brown limestones and greenish gray dolostones with thin shale and sandstone interlayers.
References
Gull River Formation Wikipedia(Text) CC BY-SA