Unit Name: Prince Edward Island redbeds
Unit Type: Lithostratigraphic
Rank: Group
Status: Formal
Usage: Abandoned
Age Interval: Late Carboniferous - Early Permian (318.1 - 270.6 ma)
Age Justification: The age is based on paleontology and its conformable relationship with the slightly older Pictou Group. Vertebrate fossils and spores and pollen support a Stephanian to Early Permian age (Langston, 1963; Barss et al., 1979; Hacquebard, 1972).
Province/Territory: New Brunswick; Prince Edward Island
Originator: van de Poll, 1983.
Type Locality:
All of Prince Edward Island.
Distribution:
Exposed throughout Prince Edward Island, the redbeds range in thickness from about 250 m in the western part to 1,000 m in the central part of the island. Each megacyclic sequence is at least 300 m thick; subcyclic sequences are up to 100 m thick. The base of megacyclic sequence I and top of megacyclic sequence IV are not exposed.
Lithology:
Four major fining-upward megacyclic sequences and two subcyclic sequences, each comprising a spectrum of lithologies ranging from greyish-red pebble and cobble conglomerate (quartzite, quartz, rhyolite clasts) near the base, through reddish-brown, coarse- to fine-grained, arkosic wacke in the middle, to very fine-grained arkosic wacke, silt, and claystone at the top. Provenance was from the southwest and south.
Relationship:
The Prince Edward Island (PEI) Redbeds gradationally and apparently conformably overlie the coal-bearing grey and red strata of the Upper Carboniferous to Permian Pictou Group of New Brunswick and Nova Scotia. The Pictou Group occurs in four regions of the Maritimes: (1) the Cumberland Subbasin of northwestern Nova Scotia, which extends under the Northumberland Strait to Prince Edward Island, (2) the New Brunswick Platform; (3) the Minas Subbasin of Nova Scotia; and (4) the Ainslie area of southeastern Cape Breton Island, Nova Scotia (Gibling pers. comm. in 1984).
History:
Rocks of the PEI Redbeds were first described by Dawson (1842) and comprehensively reviewed by Milligan (1949). Howie and Cumming (1963) interpreted the Pictou Group as exceeding 3,000 m in eastern Prince Edward Island. Bedrock studies in the southeastern and central part of Prince Edward Island, undertaken by the Geological Survey of Canada, resulted in the first attempts to subdivide the redbeds on lithological criteria (Frankel, 1966; Frankel and Crowl, 1970). The most recent comprehensive work involving the bedrock geology of Prince Edward Island was by van de Poll (1983).
Other Citations:
Barss et al., 1979; Dawson, 1842; Frankel, 1966; Frankel and Crowl, 1970; Hacquebard, 1972; Howie and Cumming, 1963; Langston. 1963; Milligan, 1949; van de Poll, 1983.
Source: LEXICON_NB
Entry Reviewed: No
Name Set: Lithostratigraphic Lexicon
LastChange: 24 May 2007