Calibrating geologic strata, dinosaurs, and other fossils at Dinosaur Provincial Park (Alberta, Canada) using a new CA-ID-TIMS U–Pb geochronology

A new U–Pb geochronology study reveals that the 100-meter-thick stratigraphic section at Dinosaur Provincial Park spans approximately 2.43 million years, with rock accumulation rates of around 3.65 cm per thousand years. This high-resolution chronostratigraphy updates long-standing K–Ar and 40 Ar/39 Ar dating, providing precise temporal constraints on bentonites, formational contacts, and biozones. The study also identifies a regional increase in accommodation at ~76.3 million years ago, aligning with patterns observed across Alberta and Montana. Dinosaur assemblage zones show durations of ~700–600 thousand years, shorter than those in the overlying Horseshoe Canyon Formation, suggesting potential ecological shifts linked to the withdrawal of the Western Interior Seaway.

Eberth, D. A., Evans, D. C., Ramezani, J., Kamo, S. L., Brown, C. M., Currie, P. J., & Braman, D. R. (2023). Calibrating geologic strata, dinosaurs, and other fossils at Dinosaur Provincial Park (Alberta, Canada) using a new CA-ID-TIMS U–Pb geochronology. Canadian Journal of Earth Sciences, 60(12), 1627–1646. https://doi.org/10.1139/cjes-2023-0037