Atanekerdluk (1850s collections) (Paleocene of Greenland)

Where: Greenland (70.1° N, 52.2° W: paleocoordinates 62.3° N, 22.8° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Naujat Member (Atanikerluk Formation), Selandian (61.6 - 59.2 Ma)

• Koch identified the Upper Atanikerdluk A flora and the Upper Atanikerdluk B flora of Heer (1883a, b) in the basal part of the formation (lowermost Naujât Member). A maximum age for the Atanikerluk Formation is obtained from the NP4 – possibly early NP5 marine dinocysts in the underlying Eqalulik Formation (Nøhr-Hansen et al. 2002). Samples from the volcanic Ordlingassoq and Rinks Dal Members give radiometric ages of 60.7–61.1 ± 0.5–1.0 Ma, recalculated from Storey et al. (1998). This indicates an early to mid-Paleocene (possibly Selandian) age for the Atanikerluk Formation.

Environment/lithology: lacustrine; lithified, black, gray mudstone

• The mudstones are interpreted as lacustrine deposits on the basis of the high C/S ratios, the absence of pyrite, the presence of terrestrial fossils (macrofossil plants, spores and pollen) and the general absence of marine dinocysts.

•As a result of the opening of the Labrador Sea in Late Mesozoic to Early Cenozoic times, a complex of linked rift basins stretching from the Labrador Sea to northern Baffin Bay developed along West Greenland. Two main episodes of regional rifting and basin development during this time have been documented in the area: an episode of Early Cretaceous rifting, and a Late Cretaceous – Early Paleocene rift episode prior to the start of sea-floor spreading in mid-Paleocene time.

• The Naujât Member comprises dark grey to black mudstones with thin, discontinuous layers of sandstones and thin tuff beds.

Size class: macrofossils

Preservation: mold/impression

Collected by Inglefield, Colomb, Olrik, M'Clintock in 1854, 1859

• Captain Inglefield and Lieutenant Colomb visited Atanekerdluk in summer 1854. Inglefield's specimens were given to the Geological Survey in London; Colomb's to the Royal Museum in Dublin. Mr. Olrik collected specimens from the same place in August 1859 and gave them to Sir Leopold MacClintock, who later brought them to Dublin. Olrik made additional collections that are in Copenhagen.

Primary reference: O. Heer. 1868. Fossile Insecten von Nordgrönland. Flora Fossilis Arctica: Die Fossile Flora der Polarländer 1:129-130 [M. Clapham/M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 152291: authorized by Matthew Clapham, entered by Matthew Clapham on 16.11.2013

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Insecta
 Blattodea - Mesoblattinidae
Blattidium fragile n. sp.
Blattidium fragile n. sp. Heer 1868 cockroach
 Coleoptera - Trogossitidae
Trogosita insignis n. sp.
Trogosita insignis n. sp. Heer 1868 bark gnawing beetle
coll. Olrik
 Coleoptera - Chrysomelidae
Chrysomelites fabricii n. sp.
Chrysomelites fabricii n. sp. Heer 1868 leaf beetle
 Hemiptera - Pentatomidae
Pentatoma boreale n. sp.
Pentatoma boreale n. sp. Heer 1868 stink bug