The Sedimentology of Palaeontology: How to Accumulate Highly Fossiliferous Deposits

Presented by Jon Noad of the University of Adelaide, March 10, 2022. Macrofossils can be found in almost every sedimentary environment, but the relative abundance and distribution of these fossils varies widely. Many factors are at work to concentrate fossil deposits, falling into two categories: how the fossils accumulate within any setting; and how fossils are later exposed in outcrop. Accumulation rates depend on five key factors: the fecundity of the setting; winnowing; low deposition rates; episodic or periodic events; and catastrophic events. Depositional settings ranging from fluvial to deep marine will be examined to see which of these factors is prevalent in preserving exceptional fossil deposits, with a variety of case studies including Dinosaur Provincial Park and North America as a whole. This presentation also explores the impact of factors like the robustness of the organism, cementation, and weathering profiles on preservation.