Middle Paleozoic Rocks
Middle Paleozoic belts are recognized across the Canadian Appalachian region from Quebec to Nova Scotia, and across the island of Newfoundland. Middle Paleozoic rocks are most extensive along the Quebec-Nova Scotia transect and from northwest to southeast they define the Gaspé, Fredericton, Mascarene, Arisaig, Cape Breton, and Annapolis belts. Middle Paleozoic rocks are less abundant in Newfoundland. From west to east they define the Clam Bank, Springdale, Cape Ray, Badger, Botwood, La Poile, and Fortune belts (Map 2).
Rocks of the middle Paleozoic belts do not express the early Paleozoic zonation of the orogen, except in a few cases where middle Paleozoic rocks occur within the confines of a particular zone.
The middle Paleozoic belts are less continuous than early Paleozoic zones and there have been few attempts to correlate middle Paleozoic rocks and interpret their significance for the entire Canadian Appalachian region. This is because (a) there are few complete sections with fossiliferous rocks so that the record is fragmentary, (b) occurrences in some places are small and of unknown age, thus precluding broad correlations and linkages across the orogen, (c) there are no middle Paleozoic ophiolite suites, few mélanges, and other rocks that can be related to píate boundaries, (d) contrasts among middle Paleozoic faunas are less pronounced than those among early Paleozoic faunas, and (e) many middle Paleozoic rocks are terrestrial redbeds and associated volcanic rocks that are post accretionary cover sequences, some of which overstep the early Paleozoic elements of the orogen.
Stratigraphic sections of most
Figures & Tables
This volume focuses on the highly populated Canadian Appalachian region. The chapter on the East Greenland Caledonides stands alone and there is no attempt to integrate the geological accounts of the two far removed regions. Rocks of the Canadian Appalachian region are described under four broad temporal divisions: lower Paleozoic and older, middle Paleozoic, upper Paleozoic, and Mesozoic. The rocks of these temporal divisions define geographic zones, belts, basins, and graben, respectively. The area is of special interest because so many modern concepts of mountain building are based on Appalachian rocks and structures.