Absence of evidence of climate-driven cycles in Carboniferous deposits of Joggins, Nova Scotia, Canada: influence of salt withdrawal tectonics on deposition and pedogenesis

A new analysis of Carboniferous deposits at Joggins Fossil Cliffs, Nova Scotia, challenges the long-held assumption that glacio-eustatic cycles drove sedimentation during the Late Paleozoic Ice Age. By applying threshold autoregressive modeling to 474 fluvial aggradational cycles and analyzing lithological variations across 1,655 beds, researchers found no statistically significant cyclicity in sediment thickness, paleosol development, or sandstone content. Instead, the study attributes rapid subsidence and sediment accumulation to halokinetic tectonics—ductile deformation of deep salt deposits—rather than climate-driven processes. This finding suggests that tectonic activity, not glacial cycles, was the primary driver of fluvial sedimentation in the Cumberland Basin, explaining the preservation of coal-rich units and fossil forests along the cliffs.

Letourmy, Y., Driese, S. G., & Sims, J. R. (2021). Absence of evidence of climate-driven cycles in Carboniferous deposits of Joggins, Nova Scotia, Canada: influence of salt withdrawal tectonics on deposition and pedogenesis. Journal of Sedimentary Research, 91(2), 167–185. https://doi.org/10.2110/jsr.2020.78