Assessing vertical bioturbation intensity from bedding planes

Bedding planes hold significant value in ichnological analyses as they improve the recognition of ichnotaxa and yield important insights into the distribution and morphology of trace fossils. However, a significant limitation lies in the challenge of accurately estimating bioturbation intensity from bedding planes. This is in part because current approaches do not establish a connection between bioturbation intensity as seen on bedding planes (plan view) and in cross-section (elevation view). This disconnect complicates the integration of bedding plane assessments into more conventional datasets collected from elevation view. Seventy-seven million Monte Carlo simulations were performed on 11 non-palimpsest Skolithos assemblages, each with varying constraints on burrow length and diameter. These simulations were used to investigate the range and frequency of cross-sectional bioturbation intensities across a spectrum of bedding plane intensities (2–50%). The results show that elevation view bioturbation intensity can be reliably approximated by multiplying plan view bioturbation intensity by the average burrow length relative to the bed thickness, independent of burrow diameter. These findings improve the ichnological analysis of bedding planes for vertical trace fossil assemblages and offer a framework for future research into more complex assemblages.