Cobalt: The Geology

The Cobalt and Lake Timiskaming region is an "outlier" (an area of rocks surrounded by rock of older age) of 650 square kilometers located in northern Ontario and parts of Quebec, Canada. To the right, geology students are shown walking the shores of Lake Timiskaming. It includes part of the northern Ontario clay belt, a rich agricultural area. The younger rock is Ordovician (425 to 500 million years old) and Silurian (405 to 425 million years old) in age, and is sedimentary (A layered rock resulting from the consoldiation of sediments) in nature and lies well within the borders of the older Precambrian shield. The area is bounded by several normal faults, including the Lake Timiskaming West Shore Fault, The Mackenzie Fault and the Blanche River Fault. The sediments are approximately 230 meters deep, and can be seen in sporatic outcrops around the region. The disjointed nature of these outcrops is due in part to the faulting of the area. The preservation of the outlier is thought to be due to post-Silurian rifting, related to the separation of North America and Europe during the Cretaceous. The area boasts small patches of sandstone from the Guigues Formation(Ordovician), poorly exposed sections of the Bucke Formation(Ordovician), The well exposed Farr Formation(Ordovician), the Dawson Point Formation (Ordovician, borehole information only) the poorly exposed Wabi Formation (Silurian) and excellent outcrops of the Thornloe Formation (Silurian). While the entire area is interesting, The Farr and Thornloe Formations are the most interesting in terms of Paleoecology and Fossils, and thus will be presented to you in more detail. To the left, A view of the outlier, exposed along the shores of Lake Tamiskaming.

Formation Rock Types

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