Pakowki Formation
The Pakowki Formation is a stratigraphical unit of Campanian age in the Western Canadian Sedimentary Basin.
Pakowki Formation Stratigraphic range: Campanian | |
---|---|
Type | Geological formation |
Underlies | Foremost Formation, Judith River Formation |
Overlies | Milk River Formation |
Thickness | up to 200 metres (660 ft)[1] |
Lithology | |
Primary | Shale |
Other | Siltstone, sandstone |
Location | |
Coordinates | 49.19251°N 111.06669°W |
Region | WCSB |
Country | |
Type section | |
Named for | Pakowki Lake |
Named by | D.B. Dowling, 1916 |
It takes the name from Pakowki Lake, and was first described in outcrop along the Pakowki Coulee by D.B. Dowling in 1916.[2]
Lithology
The Formation is composed of grey mudstone. [1] Olive siltstone and very fine grained sandstone can occur locally. A thin pebble conglomerate marks the base.
Distribution
The Pakowki Formation reaches a maximum thickness of 200 metres (660 ft) in central Saskatchewan.[1] It reaches into southern Alberta, thinning out as it progresses westwards towards the Canadian Rockies foothills.
Relationship to other units
The Pakowki Formation is abruptly overlain by the Milk River Formation and gradationally overlays the Judith River Formation or Foremost Formation.[1]
It is equivalent to the upper part of the Lea Park Formation in central Alberta. It is not differentiated from the Riding Mountain Formation to the east into eastern Saskatchewan and Manitoba.
References
- Lexicon of Canadian Geologic Units. "Pakowki Formation". Retrieved 2010-01-01.
- Dowling, D.B., 1916. Water Supply, Southeastern Alberta (Contains Geological Map 1604); Geological Survey of Canada, Summary Report 1915, pp. 102-110.