Type Locality:

None designated. A composite lectostratotype was designated by Bell (1929), including sections on the east bank of the Avon River, Hants County, at Windsor (NTS 21 A/16); Maxner Point, the mouth of the Kennetcook River (NTS 21 H/1); and the mouth of the Avon River at Cheverie (NTS 21 H/1). Much of the composite lectostratotype is no longer exposed due to drainage and causeway construction at Windsor. A good reference section, however, occurs between Avondale and the mouth of the Kennetcook River, on the cast bank of the Avon River, Hants County, Nova Scotia (NTS 21 A/16; 21 H/1).

Distribution:

The Windsor Group is about 920 m thick in the type area (if the Tennycape Formation is not equivalent to part of subzone B). It thickens to the northeast and appears to be thickest in central Cape Breton (Moore, pers. comm.). The sediments were deposited in a seaway or large basin which extended from Newfoundland through the Magdalen Islands to Cape Breton, mainland Nova Scotia and southern New Brunswick. The outcrop belt of the Windsor is about 600 km long and up to 150 km wide.

Lithology:

Dawson (1873) defined the Windsor as a "marine formation holding characteristic shells and corals of the Lower Carboniferous Period, and containing in addition to the limestones thick beds of sandstone, marl and clay, usually red, and of gypsum". In the type area, the Windsor Group consists of, in ascending order, a lower part (subzone A, Bell, 1929) of thin basal carbonates (Macumber Formation, Gays River Formation), overlain by massive evaporites (White Quarry (Vinland) formation); a middle part of interbedded evaporites and minor red clastics, chiefly siltstones and thin carbonates (subzone B, Bell, 1929); an upper part (subzones C to E) of interbedded clastics and carbonates with minor evaporites. The clastics of the "Upper Windsor" are coarse-grained near highland source areas, but elsewhere are fine-grained. The carbonates contain diversified marine faunas and the clastics are mainly continental and poorly fossiliferous. Giles (1981) included in the Windsor Group of Nova Scotia, in ascending order, the Macumber, Pembroke, Gays River, Carrolls Corner, Meaghers Grant, Stewiacke, Tennycape, MacDonald Road, and Green Oaks formations. Giles (1981) considered the Watering Brook Formation (grey and red siltstone with evaporates) in the Shubenacadie Subbasin to be in the Canso Group. In the Windsor area, similar rocks are considered to be an upper part of the Murphy Road formation of the Windsor Group (Moore, pers. comm. in Giles, 1981). In New Brunswick the Windsor Group includes, in ascending order, the Macumber/Gays River formations, the Parleeville, Upperton, and Cassidy Lake formations. The Gays River Formation is thought to represent a marginal bank facies and may be equivalent to the Macumber, Upperton, and Cassidy Lake.

Relationship:

The Windsor Group unconformably overlies the Cambrian to Ordovician Meguma Group, Acadian granites, and the ?Upper Devonian to Lower Carboniferous Horton Group on mainland Nova Scotia. The Windsor Group is generally unconformably overlain by the Upper Carboniferous Scotch Village Formation of the Pictou Group. The Lower Carboniferous Codroy Group of Newfoundland is similar in age and lithologies. The Upper Windsor Group (subzones C, D, E) is absent in New Brunswick, where correlative strata are continental.

History:

Brown and Smith (in Haliburton, 1829) were the first to indicate a Carboniferous age for the "Gypsiferous Series" of Cumberland County, Nova Scotia, but did not correlate these strata with the subsequently designated type area in the western part of the Minas subbasin. Lyell (1843) gave the first description of the Windsor and correctly determined that the Gypsiferous Series in the province was pre-Coal Measure and Early Carboniferous in age, on both faunal and stratigraphic grounds. Subsequently, Dawson (1847) subdivided the "gypsiferous formations" into a lower estuarine or lacustrine plant-bearing formation and an upper marine formation. In 1873, he applied the term Windsor Series to the former and Horton Series to the latter. In 1867, Hartt published the first detailed lithologic and faunal description of what became Bell's (1927a) type section of the Windsor Group at Windsor. Hartt also assigned specific names to some of the major fossiliferous carbonate units of the group. These were believed to lie in the following ascending order, separated by fine-grained clastics: Avon Limestone, Oolitic Fossiliferous Limestone, Kennetcook Limestone, Windsor Limestone, and Stewiacke Limestone. Dawson (1868) grouped Hartt's units into a lower and upper series and modified some of the names as follows: Lower Series - Crinoidal Limestone (Oolitic Fossiliferous); Spirifer Limestone (Avon); Upper Series - Productus Limestone (Stewiacke); Aviculopecten Limestone (Windsor); Zaphrentis or Phillipsia Limestone (Kennetcook).Bell (1927a) divided the Windsor into two "sub-epochs" termed Lower Windsor (Zone of Composita dawsoni) and Upper Windsor (Zone of Martinia galataea), which subsequently were termed zones (Bell, 1929). The Lower Windsor was further subdivided into Subzone A, typical lithological members being designated as the "Limestone at Cheverie and the Gypsum at Cheverie", and Subzone B characterized by Diodoceras avonensis (Dawson). Typical lithological members from the base upwards were termed: Maxner limestone, Gypsum below Miller limestone, Miller limestone, and Gypsum. The Maxner is equivalent to the Stewiacke and the Miller to the Windsor of Hartt (1867). The Upper Windsor was subdivided into subzones: C, characterized by Dibunophyllum lambii (Bell) and Nodosinella priscilla (Dawson); D, characterized by Productus semicubiculus (Bell); and E, characterized by Caninia dawsoni (Lambe) and Chonetes politus. In 1929, Bell provided a composite type section for the Windsor Group which included some 61 rock units. The previously designated members of Hartt (1867) were placed in their correct stratigraphic position. Weeks (1948) introduced the terms Macumber and Pembroke, the Lower Sulphate bed, and Tennycape Formation for the sequence of units forming the base of the Windsor Group in the Londonderry and Bass River map areas of Colchester and Hants counties. Only the first and last of these units are considered valid formations (Moore, pers. comm.). Bell (1958) added subzone F to the Windsor sequence but this has subsequently been shown to be incorrect and equivalent to subzone C (Moore and Austin, 1979). Moore (1967) recognized the distinctive faunal and lithologic nature of seven major lithologic units in the upper part (subzones C to E) of the Windsor Group, which he traced throughout most of the Minas subhasin. Newly named members, formally designated, were the Herbert River, Brooklyn Station, Meander River, and Wallace Point limestones. Giles and Boehner (1979) dropped the lithological designation, i.e. limestone member, from all member names of the Windsor Group, although they were not in contravention of Article 30f of the North American Stratigraphic Code, 1983. Another member, the Avon, was previously designated by Bell (1929). Subsequently, Moore (Moore and Ryan, 1976; Keppie, 1979) introduced the formational names Vinland, Miller Creek, Wentworth, and Murphy Road. Giles (1982) and Giles and Boehner (1982a, 1982b) have introduced the following names for formations in the Eureka (NTS 11 E/7) area, Pictou County: Holmes Brook, Bridgeville, Forbes Lake, and Churchville (all informal); for the Shubenacadie area: Gays River, Meaghers Grant, Carrolls Corner, Stewiacke, Elderbank, MacDonald Road, and Green Oaks; for the Antigonish area: Bridgeville (informal), Hartshorn, Lakevale, Wallace Brook, Addington, and Hood Island. Kirkham (1985) compiled a report on the base metals in the oolitic and stromatolitic limestones of the upper Windsor (Codroy) Group in the Atlantic Provinces.

Other Citations:

Brown and Smith, 1829.

References:

Bell, W.A., 1927a. Outline of Carboniferous stratigraphy and geologic history of the Maritime Provinces of Canada: Proceedings and Transactions of the Royal Society of Canada, Third Series, vol. 21, section 4, pp. 75-108.

Bell, W.A., 1929. Horton-Windsor district, Nova Scotia; Geological Survey of Canada. Memoir 155, 268 p.

Bell, W.A., 1944b. Carboniferous rocks and fossil floras of northern Nova Scotia; Geological Survey of Canada, Memoir 238, 277 p.

Bell, W.A., 1958. Possibilities for occurrence of petroleum reservoirs in Nova Scotia; Province of Nova Scotia, Department of Mines, Miscellaneous Publication 58-2, 177 p.

Brown, R. and Smith, R., 1829. Geology and mineralogy of Nova Scotia, pp. 414-453: in T.C. Halibur-ton (ed.), An Historical and Statistical Account of Nova Scotia, vol. 2.

Dawson, J.W., 1847. The Gypsum of Nova Scotia: Academy of Natural Science, Philadelphia, Proceedings, vol. 3, pp. 270-274.

Dawson, J.W., 1868. Acadian geology (second edition); MacMillan and Company, London, 694 p.

Dawson, J.W., 1873. Report on the fossil plants of the Lower Carboniferous and Millstone Grit formations of Canada; Geological Survey of Canada, Separate Report 430, 47 p.

Giles, P.S. and Boehner, R.C., 1979. Carboniferous stratigraphy of the Shubenacadie and Musquodoboit basins, central Nova Scotia; Nova Scotia Department of Mines and Energy, Open File Report ME 410, 28 p. + single 1:100 000 scale map sheet.

Giles, P.S. and Boehner, R.C., 1982a. Geological map of the Shubenacadie and Musquodoboit basins, central Nova Scotia, parts of NTS 11D/13, 11D/14, 11D/15 11E/02, 11E/03, 11E/04, 11E/05, 11E/06 and 11E/07; Nova Scotia Department of Mines and Energy, Map ME 1982-4, Scale: 1:50 000.

Giles, P.S. and Boehner, R.C., 1982b. Subdivision and regional correlation of strata of the upper Windsor Group, Cape Breton lsland and central Nova Scotia, pp. 69-78: in K.A. Mills (ed.), Report of Activities, 1981; Nova Scotia Department of Mines and Energy, Mineral Resources Division, Report 82- 1,139 p.

Giles, P.S., 1981. Major transgressive-regressive cycles in Middle to Late Visean rocks of Nova Scotia: Nova Scotia Department of Mines and Energy, Mineral Development Division, Paper 81-2, 27 p.

Giles, P.S., 1982. Eureka area: Nova Scotia Department of Mines and Energy, Mineral Resources Division, Map 82-3.

Haliburton, T.C., 1829. An historical and statistical account of Nova Scotia, in two volumes, illustrated by a map of the Province and several engravings: Section III, Geology and Mineralogy, vol. II, Halifax, pp. 414-453.

Hartt, C.F., and Dawson, J.W., 1867. On a subdivision of the Acadian Carboniferous limestones, with a description of a section across these rocks at Windsor, N. S.; The Canadian Naturalist and Geologist, vol. 3, no. 3, pp. 212-224.

Keppie, J.D., 1979. Geological map of the province of Nova Scotia: Nova Scotia Department of Mines and Energy, Map 79-1, scale 1:500 000.

Kirkham, R.V., 1985. Base metals in upper Windsor (Codroy) Group oolitic and stromatolitic limestones in the Atlantic Provinces, Project 700059, in, Current Research, Part A, Economic Geology, Blackadar, R.G., Morgan, W.C., Dumych, H., Griffin, P.J., Ollerenshaw, N.C., Dufour, M.-F., and Vincent, L.E. (Eds.); Geological Survey of Canada, Paper 85-1A, pp. 573-585.

Lyell, C., 1843. On the coat formation of Nova Scotia and the age and relative position of the gyp-sum and accompanying marine limestones: Proceedings, Geological Society of London, vol. 4, pp. 184-186; also American Journal of Science, vol. 45, pp. 356-359.

Mamet, B.L., 1970. Carbonate microfacies of the Windsor Group (Carboniferous), Nova Scotia and New Brunswick; Geological Survey of Canada, Paper 70-21, 121 p.

Moore, R.G. and Austin, J.A., 1979. The Herbert River and Musquodoboit limestone members, keys to the reconstruction of the Fundy Depositional Trough in upper Windsor, Late Mississipian time in the Atlantic area of Canada: Abstracts of Papers, Ninth International Congress on Carboniferous Stratigraphy and Geology, Urbana, Illinois, pp. 141-142.

Moore, R.G. and Ryan, R.J., 1976. Guide to the invertebrate fauna of the Windsor Group in Atlantic Canada; Nova Scotia Department of Mines and Energy, Paper 76-5, 57 p.

Moore, R.G., 1967. Lithostratigraphic units in the upper part of the Windsor Group, Minas Sub-basin, Nova Scotia, pp. 245-266: in E.R.W. Neale and H. Williams (eds.), Collected Papers on Geology of the Atlantic Region - Hugh Lilly Memorial Volume; Geological Association of Canada, Special Paper 4, 292 p.

Utting, J., 1978. Palynological investigation of the Windsor Group (Mississippian) of Port Hood lsland and other localities on Cape Breton lsland, Nova Scotia, in, Current Research, Part A, Blackadar, R.G., Griffin, P.J., Dumych, H., and Irish, E.J.W. (Eds. and Compilers); Geological Survey of Canada, Paper 78-1A, pp. 205-207.

Weeks, L.J., 1948. Londonderry and Bass River map-areas, Colchester and Hants counties, Nova Scotia: Geological Survey of Canada, Memoir 245, 86 p.