Springhill Mines Formation

Unit Name: Springhill Mines Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Langsettian (318.5 - 317.7 ma)
Age Justification: On the basis of palynology, Dolby (1991) assigned the strata of the MacCarrons River Member at the coast an earliest Westphalian B (Duckmantian) age. Utting et al. (2010) assigned these same strata to their Raistrickia fulva spore zone, which they interpreted to be Langsettian. The absence of mairne index fossils and the possible ecological exclusion of index palynomorphs contributes to the disparate biostratigraphic interpretations.
Province/Territory: Nova Scotia

Originator: Ryan et al., 1991; revised by Rygel et al., 2014

Type Locality:

Springhill area, Cumberland County, Nova Scotia. The few outcrops include along Coal Mine Brook, immediately to the west of Springhill. Because of the paucity of outcrops, Ryan et al. (1991) based much of their data on a composite section compiled from diamond-drill holes in the Springhill area (NTS 11 F/16). Reference locality (designated by Ryan et al., 1991): along the shore of Chignecto Bay from 400 m north of MacCarron River south to a point 500 m north of Ragged Reef, Joggins, Cumberland County, Nova Scotia (NTS 21 H/9).

Distribution:

In the Springhill area, the formation is 660 m thick; in the coastal section at Joggins it is 610 m. Seismic data indicate a thickening of the Springhill Mines towards the centre of the Athol Syncline. The main thicknesses appear to be in the western part of the Cumberland Basin. In the eastern part of the basin, the formation is not exposed but it appears to have been encountered in four drill holes in the Wallace Syncline.

Locality Data:

Thickness(m): Minimum 610, Maximum 697.

Lithology:

The main lithologies are interstratified, grey, sublitharenitic sandstones, commonly medium-grained, grey, sideritic mudstones, with numerous, thin coal seams, which may be up to 4.3 m thick in the type locality, and rare limestones, commonly cone-in-cone. The Joggins section shows rhythmic sequences of poorly developed coals, abundant red mudstone that increases up section, and numerous, thin (up to 2 m) sandstones. Fine to coarse ratios vary from 1:4 at Joggins to 4:3 at Springhill. When they form multistoried sequences, the sandstones can be up to 22 m thick; when they are single sheets, they are about a metre.

Fossils:

Spores: Raistrickia fulva zone

Paleo Environment:

terrestrial, fluvial

Paleo Climate:

humid

Relationship:

The Springhill Mines Formation is one of eight formations of the Cumberland Group (Davies et al., 2005). In the type area, the Springhill Mines Formation is laterally transitional to the upper part of the Polly Brook Formation. At the southern margin of the Cumberland Basin, the formation conformably overlies and interfingers with the Polly Brook. In the Joggins section, where the Polly Brook is absent, the Springhill Mines conformably overlies the Joggins Formation. The formation is conformably overlain by the Ragged Reef Formation. Across this upper boundary there is an increase in red mudstones and a decrease in the number of coal seams.

History:

Logan (1845) included the strata of the Springhill Mines Formation in his Division 3 in his interpretation of the Joggins section. Bell (1914) regarded them as part of his proposed Joggins Formation. Bell (1938a) included the same rocks in his informal unit 6c. Shaw (1951) considered the strata to be part of his "Fine Coal-bearing Facies". Copeland (1959) introduced the term Cumberland "fine facies", also used by Calder (1984) and Ryan (1985). Ryan et al. (1991) formalized the name Springhill Mines Formation. Rygel et al. (2014) reassigned a 16.9 m thick interval of dark laminated mudrocks and sharp-based sandstones to the underlying Joggins Formation.

References:

Bell, W.A., 1914. Joggins Carboniferous section, Nova Scotia; Geological Survey of Canada, Summary Report for 1912, pp. 360-371.

Bell, W.A., 1938a. Springhill sheet, Cumberland and Colchester counties, Nova Scotia; Geological Survey of Canada, "A" Series Map 337A, Scale: 1:63 360 or 1 Inch to 1 Mile.

Calder, J.H., 1984. Sedimentology studies within the Springhill coalfield, Cumberland County, Nova Scotia, pp. 1-6: in J. Szostak and K.A. Mills (eds.), Report of Activities, 1983; Nova Scotia Depart-ment of Mines and Energy, Mineral Development Division, Report 84-1, 341 p.

Copeland, M.J., 1959. "Coalfields, west half Cumberland County, Nova Scotia"; Geological Survey of Canada, Memoir 298, 89 p.

Davies, S.J., Gibling, M.R., Rygel, M.C., Calder, J.H. and Skilliter, D.M., 2005. The Pennsylvanian Joggins Formation of Nova Scotia: sedimentological log and stratigraphic framework of the historic fossil cliffs; Atlantic Geology, vol. 41, pp. 115-142.

Dolby, G. 1991: The palynology of the western Cumberland Basin, Nova Scotia. Nova Scotia Department of Mines and Energy, Open File Report 91-006, 39 p.

Logan, W.E., 1845. Section of the Nova Scotia Coal Measures, as developed at the Joggins on the Bay of Fundy, in descending order, from the neighbourhood of the West Ragged Reef to Minudie, reduced to vertical thickness; Geological Survey of Canada, Report of Progress for 1843, pp. 92- 159.

Ryan, R.J., 1985. Upper Carboniferous strata of the Tatamagouche Syncline, Cumberland Basin, Nova Scotia; In: Geological Survey of Canada, Current Research Part B, Paper 85-1B, pp. 481-490.

Ryan, R.J., Boehner, R.C. and Calder, J.H. 1991. Lithostratigraphic revisions of the upper Carboniferous to lower Permian strata in the Cumberland Basin, Nova Scotia and the regional implications for the Maritimes Basin in Atlantic Canada; Bulletin of Canadian Petroleum Geology, vol. 39, No. 4, pages 289-314.

Rygel, M.C., Sheldon, E.P., Stimson, M.R.,Calder, J.H., Ashley, K.T. and Salg, J.L. 2014. The Pannsylvanian Springhill Mines Formation: sedimentological framework of a portion of the Joggins Fossil Cliffs UNESCO World Heritage Site; Atlantic Geology, volume 50, pp. 249-289.

Utting, J., Giles, P.S. and Dolby, G. 2010. Palynostratigraphy of Mississippian and Pennsylvanian rocks, Joggins area, Nova Scotia and New Brunswick, Canada. Palynology volume 34, no. 1, pages 43-89.

Source: GEOLOGICAL SURVEY OF CANADA
Contributor: R.J. Ryan; G.L. Williams; P.H. Davenport
Entry Reviewed: No
Name Set: Lithostratigraphic Lexicon
LastChange: 27 Feb 2015