Late Ordovician brachiopods from east-central Alaska, northwestern margin of Laurentia

• Main Authors: Jin, Jisuo, Blodgett, Robert
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2020
• Subjects: Late Ordovician; Alaska; Mackenzie mountains; Siberia
• Online Access: https://doi.org/10.5061/dryad.31zcrjdh2

A Late Ordovician brachiopod fauna from the Black River quadrangle (D-1 1:63,360 scale) of east-central Alaska comprises taxa typical of the Late Ordovician brachiopod fauna in the pericratonic epeiric seas of Laurentia, including Hesperorthis pyramidalis, Plaesiomys occidentalis, Eoplectodonta sp., Holtehdalina sp., Leptaena sp., Brevilamnulella minuta n. sp., Tcherskidium tenuicostatum n. sp., Rhynchotrema iowense, and Whitfieldella sp. The presence of Plaesiomys occidentalis and Tcherskidium tenuicostata n. sp. indicates a latest Katian age by correlation with similar species in the Mackenzie Mountains, southern Manitoba, Anticosti Island, the American mid-continent, Kolyma, and Siberia. Cluster analysis based on 20 well-studied late Katian brachiopod faunas from various regions within Laurentia and elsewhere in other tectonic plates suggests that the small brachiopod faunule from Alaska has the strongest paleobiogeographic affinity with Laurentia, confirming that the Black River quadrangle of Alaska was part of Laurentia during the Late Ordovician. The dataset is binary: present = 1, absent = 0 Funding provided by: Natural Sciences and Engineering Research Council of Canada Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100000038 Award Number: Discovery Grant