Unit Name: Huntingdon Member
Unit Type: Lithostratigraphic
Rank: Member
Status: Formal
Usage: Currently in use
Age Interval: Ibexian (491 - 473 ma)
Age Justification: Conodont faunas provide age controls (Salad-Hersi et. al., 2003).
Province/Territory: Ontario; Quebec

Originator: Clark, 1966; amended by Bernstein, 1992

Type Locality:
The type locality described by Clark (1966) lies in the Chateauguay area, Quebec.

Distribution:
The Beekmantown Group (which contains the Huntingdon Member) thins westward from the Montréal region of southwestern Quèbec into eastern Ontario (Salad-Hersi et al., 2003).

Lithology:
The Huntingdon Member consists of medium to thickly bedded, light to medium grey, pervasively burrow-mottled, fine to coarse crystalline dolomudstone with light to dark brownish grey, thinly bedded to microbially laminated, mudcracked, fine crystalline dolomudstone interbeds in its lower two thirds. Thick beds of bioclastic dolopackstone to rudstone that are also moderately to well burrowed are present in this lower part of the member (Salad-Hersi et al, 2003).

Fossils:
Fossils are rare; crinoid columnals and trilobite fragments (Clark, 1966).

Relationship:
The Huntingdon Member belongs to the Beauharnois Formation (Beekmantown Group) in southwestern Quèbec. It lies conformably above the Ogdensburg Member and below the Carillon Formation.

History:
Efforts to divide the Beekmantown Group into workable stratigraphic units have been numerous over the last century (Logan 1863; Raymond 1913; Belyea 1952; Byrne 1958; Clark 1966, 1972; Clark and Globensky 1976; Globensky 1981a, 1981b, 1982, 1986, 1987) and have resulted in a wide variety of stratigraphic nomenclature using mixed biostratigraphic, chronostratigraphic, and lithostratigraphic approaches. Clark (1966) first defines the Huntingdon Member in his report on the Chateauguay area. Bernstein (1992) has documented the historical evolution of the stratigraphic nomenclature applied to the Beekmantown Group, and he further subdivided the Beauharnois Formation into the lower Ogdensburg Member and the upper Huntingdon Member (Salad-Hersi, et. al., 2003).

References:
Belyea, H.R., 1952. Notes on the Devonian System or the north-central plains of Alberta; Geological Survey of Canada, Paper 52-27, 65 p.
Bernstein, L., 1992. A revised lithostratigraphy of the Lower-Middle Ordovician Beekmantown Group., St.. Lawrence Lowlands, Quebec and Ontario. Canadian Journal of Earth Sciences, 29: 2677-2694.
Clark, T.H., 1966. Châteauguay Area, Québec Department of Natural Resources, Geological Report 122, 63 p.
Clark, T.H., 1972. Montreal Area. Ministère des richesses naturelles du Québec, Geological Report, 152, 244p.
Globensky, Y., et.al., 1993. Lexique stratigraphique Canadien, vol. V-B, Région des Appalaches, des Basses Terres Saint Laurent et des Iles des Madeleine, Ministère de l'Énergie et des Ressources du Québec, DV 91-23.
Logan, W.E. 1863. Geological Survey of Canada Report of Progress for 1863.
Raymond, P.E., 1913, Excursions in Eastern Quebec and the Maritimes Provinces, Quebec and vicinity. International Geological Congress XII, Canada, Guidebook I, p. 25-48
Salad-Hersi, O., Lavoie, D., Nowlan, G.S., Reappraisal of the Beekmantown Group sedimentology and stratigraphy, Montrèal area, southwestern Quèbec: Implications for understanding the depositional evolution of the Lower-Middle Ordovician Laurentian passive margin of eastern Canada; Canadian Journal of Earth Sciences; 40, 2: pages 149-176.

Source: GSC file of geological names; T.E. Bolton and J. Dougherty (compiler)
Contributor: A.A. Coyne; G.E. McCune
Entry Reviewed: No
Name Set: Lithostratigraphic Lexicon
LastChange: 01 Apr 2008