US4, Ravenscrag Butte flora (Paleocene of Canada)

Where: Saskatchewan, Canada (49.5° N, 109.0° W: paleocoordinates 55.6° N, 85.6° W)

• coordinate stated in text

When: Ravenscrag Formation, Paleocene (66.0 - 56.0 Ma)

• The stratigraphic position of the collection is given relative to the No. 1 coal zone, which is approximately at the base of the formation. The part of US4 that contains the Mesocyparis borealis specimen directly overlies the No. 1 coal zone (south face). The part of the locality that contains the rest of the collection lies directly over the first part.

Environment/lithology: terrestrial; shale

• During the early Tertiary, most of southern Saskatchewan was a broad alluvial plain dominated by meandering river systems. Locally, at the Ravenscrag Butte site, small lakes or ponds, sluggish streams, swamps and lowland forests successively dominated the area over a period of perhaps 2 million years.
• The Ravenscrag Formation consists of interbedded, nonmarine clays, silts, sands, and lignite. The measured section at the Ravenscrag Butte site is about 67 m thick, and lithologically, the formation in divided into two facies; the lower 38 metres comprises the grey facies, the upper 29 metres, the buff facies. At a distance, the two facies are easily distinguishable on the basis of colour. Commonly, the buff facies are less than 31 m thick in measured sections due to erosion or cover at the top. There are four conspicuous beds of coal or coaly shale in the sections at Ravenscrag Butte, including the No. 1 coal zone. The fourth coal zone marks the transition from grey to buff facies. Locality US4 has brown shales for the Mesocyparis borealis specimen. Everything else in the collection is from grey shales and sands directly overlying the brown shales.

Size class: macrofossils

Preservation: adpression

Collection methods: salvage, surface (in situ),

Primary reference: E. E. McIver and J. F. Basinger. 1993. Flora of the Ravenscrag Formation (Paleocene), Southwestern Saskatchewan, Canada. Palaeontographica Canadiana 10:1-85 [R. Lupia/B. Wilborn/B. Wilborn]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 34417: authorized by Rick Lupia, entered by Brooke Wilborn on 31.08.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

 Pinales - Taxodiaceae
Metasequoia occidentalis Chaney 1951 dawn redwood
 Polypodiales - Dryopteridaceae
Onoclea hesperia Hickey 1977
 Polypodiales - Blechnaceae
Woodwardia gravida Hickey 1977
"Trapago angulata" = Quereuxia, Dicotylophyllum anomalum
"Trapago angulata" = Quereuxia
Trapago angulata comb. nov.
 Rosales - Rosaceae
Amelanchites similis
Amelanchites similis comb. nov.
Prunites maclearnii
Prunites maclearnii comb. nov.
 Proteales - Nelumbonaceae
cf. Nelumbo sp. Adanson
Nelumbago montanum n. gen. Brown 1962
Nelumbago montanum comb. nov.
 Nymphaeales - Nymphaeaceae
Paranymphaea crassifolia McIver and Basinger 1993
Archeampelos acerifolia
Archeampelos acerifolia McIver and Basinger 1993
Archeampelos acerifolia comb. nov.