Harmon Member

Unit Name: Harmon Member
Unit Type: Lithostratigraphic
Rank: Member
Status: Formal
Usage: Currently in use
Age Interval: middle Albian (108.8 - 106.4 ma)
Age Justification: The upper Harmon shale carries Gastroplites. The arenaceous microfauna of the Harmon has been described by Wickenden (1951). The palynology (Singh, 1971) records the introduction of the earliest reticulate monosulcate angiosperm pollen grains.
Province/Territory: Alberta; British Columbia

Originator: Alberta Study Group, 1954; first published by Badgley, 1952.

Type Locality:

East bank of Peace River, 6 km (3.75 mi) below the bridge at Peace River, Alberta, in Sec. 21, Twp. 84, Rge. 21W5M.

Distribution:

Thickness varies from 10 to 34 m (33 to 122 ft). Identification of the facies or time equivalent of the member is dependent on the recognition of the Cadotte, but equivalent beds in the Pine Pass area of British Columbia reach 135 m (443 ft) thickness. The Harmon can be recognized over most of the Peace River area of British Columbia and Alberta south of Twp. 88.

Lithology:

The Harmon consists of dark grey, noncalcareous firm, thin-bedded to fissile marine shale. Commonly it contains grey bentonitic shale interbeds and occasional thin beds of sandstone and siltstone.

Relationship:

The Harmon is transitionally and conformably overlain by the Cadotte Member of the Peace River Formation and conformably underlain by the Notikewin Member of the Spirit River Formation. It correlates with the Hulcross Member of the Commotion Formation of the Pine Pass area of British Columbia and with the middle shale member (Wildhorn Member, Stott, 1981) of the Scatter Formation of the Liard River area. The Harmon may be in part equivalent to part of the Mountain Park Formation in the central Alberta Foothills. A correlative relationship to the Joli Fou Formation of the Athabasca drainage has been suggested in the past, but microfaunal evidence clearly indicates the Harmon to be much older than the Joli Fou (Caldwell et al., 1978).

History:

This shale was originally called the middle shale member of the Peace River Formation (McLearn, 1918; Wickenden, 1951) . The Alberta Study Group (1954) equated it to the Joli Fou Formation, but Joli Fou equivalents lie above the Cadotte horizon, not below (Oliver, 1960).

Other Citations:

Alberta Study Group, 1954; Badgley, 1952; Caldwell et al., 1978; McLearn, 1918; Oliver, 1960; Singh, 1971; Stelck et al., 1956; Stott, 1981; Wickenden, 1951.

References:

Badgley, Peter C., 1952. Notes on the subsurface stratigraphy and oil and gas geology of the Lower Cretaceous series in central Alberta (Report and seven figures); Geological Survey of Canada, Paper No. 52-11, 12 p.

Source: CSPG Lexicon of Canadian Stratigraphy, Volume 4, western Canada, including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba; D.J. Glass (editor)
Contributor: C.R. Stelck
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 28 May 2008