Kukpowruk River 96-21 (Cretaceous of the United States)

Also known as Kukpowruk River/Cape Lisburne floras

Where: western North Slope County, Alaska (69.3° N, 163.6° W: paleocoordinates 80.2° N, 93.4° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Kukpowruk Formation, Albian (113.0 - 100.5 Ma)

• lower to middle Albian

• group of beds-level stratigraphic resolution

Environment/lithology: "floodplain"; brown, gray siltstone and coal

• Description. These are the first non-marine deposits overlying

•extensive marine units on the south limb of Howard Syncline.

•Grey/brown siltstones approximately 1 m thick overlie thin

•carbonaceous grey/black shales which in turn overlie brown, finegrained

•sandstones (marine?). The grey/brown siltstones contain

•abundant Ginkgo leaves. Above these there is a layer of grey/brown

•siltstone with abundant Pityophyllum succeeded by a coal consisting

•almost entirely of Podozamites leaves capped by lumpy sheets of

•ironstone rich in Pityophyllum and Podozamites. Podozamites predominates.

•This is capped by a 10-cm-thick grey siltstone with

•abundant Podozamites. This passes into a 0.5-m-thick poor quality,

•iron-stained coal. The coal passes up into a 3-m-thick grey siltstone

•and then a light grey, weathering to yellow, fine-grained sandstone.

•Sample 96 RAS 113 is a portion of wood from the ironstone

•overlying the first coal, 96 RAS 114 is a sample from the top of the

•first Podozamites-rich coal, and 96 RAS 115 is a sample of the

•ironstone capping the first coal.

•Interpretation. Near-marine floodplain environment supporting

•wooded mires rich in Podozamites. Podozamites was apparently a

•major coal-forming plant.

Size class: macrofossils

Collection methods: quarrying,

• Material stored at the Earth Sciences Department, The Open University, collection # 96 RAS.

Primary reference: R. A. Spicer and A. B. Herman. 2001. The Albian-Cenomanian flora of the Kukpowruk River, western North Slope, Alaska: stratigraphy, palaeofloristics, and plant communities. Cretaceous Research 22:1-40 [D. Royer/D. Royer/D. Royer]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 34369: authorized by Dana Royer, entered by Dana Royer on 28.08.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

Pityophyllum sp. Seward 1919
occurs in ironstone capping coal
 Pinales - Podocarpaceae
Podozamites spp. Braun 1843
occurs in coal and ironstone capping coal
 Equisetales - Equisetaceae