Modeling the effect of convex upward sediment deformation and horizontal core sectioning on paleolimnological data

Abstract

We analyzed photos of convex upward deformation in split sediment cores to obtain reasonable parameters with which to model the effect of convex upward deformation on paleolimnological data. Using a 3-dimensional raster model, we modeled the effect of this deformation on a hypothetical dataset. Model results indicated that convex upward sediment deformation integrates samples from an increasingly broader range of stratigraphic layers with an increasing degree of deformation. After applying deformation, extruded concentration profiles were nearly identical, despite varying the extrusion interval between 0.1 and 1 cm, suggesting there is a limit to the resolution that can be attained by horizontal sectioning if deformation occurred during sampling. Our data suggest that it is essential to determine the degree of sediment deformation caused by coring prior to conducting high-resolution analyses on horizontally sectioned samples.