Upper Jurassic-Lower Cretaceous palynostratigraphy of the Aklavik Range, Northwest Territories, Arctic Canada

• Main Author: Nguyen, Anne Van
• Other Authors: Beauchamp, Benoît, Galloway, Jennifer M., Dutchak, Alex, Henderson, Charles M.
• Format: Master Thesis
• Language: English
• Published: Science 2019
• Subjects: biostratigraphy; Ecology; Geology; Paleobotany; Paleoecology; Paleontology; Palynology; Aklavik; Aklavik Range; Arctic; Canada; Northwest Territories
• Online Access: http://hdl.handle.net/1880/110242; https://doi.org/10.11575/PRISM/36424

Quantitative palynostratigraphy of Lower Cretaceous rocks from the Aklavik Range, Northwest Territories, is used to provide insight into paleoenvironmental conditions in the Boreal Realm during the Jurassic-Cretaceous transition. Paleoenvironmental reconstruction of this time interval is based on palynoassemblages preserved in the Husky Formation (upper Tithonian – lower Berriasian). Relative abundance of ecologically-important spore and pollen taxa such as Cupressaceae-Taxaceae and Classopollis classoides pollen reveal increasing humid conditions with a seasonally arid phase during the early Berriasian. Dinoflagellate cyst assemblages preserved in the purported Martin Creek Formation (lower Berriasian) include potential biostratigraphically significant species Oligosphaeridium cf. tenuiprocessum. A revised late Albian age is proposed for the succession, which may be stratigraphically attributed to the Arctic Red Formation. High relative abundance and diversity of fern spores indicate that high moisture conditions prevailed. Trends in the relative abundance of gymnosperm pollen suggest a transition from cool to warm temperatures during this time period.