NEW MODEL FOR THE EMPLACEMENT, BIOTURBATION, AND PRESERVATION OF FINE-SCALED SEDIMENTARY STRATA

Abstract

We present a new quantitative model for the formation and preservation of sedimentary fabric based on interacting sedimentation and bioturbation. The model is one-dimensional and is forced by fluctuation of the sedimentation rate, which affects deposition of sediment possessing primary (depositional) fabric. Primary fabric is modified by bioturbation, which is represented as a depth-limited reaction term. Model output includes depth in seabed and preservation quotient, a measure of relative preservation of primary versus biogenic fabric at each depth. The required parameters (sedimentation rate and bioturbation rate) can be derived from studies of seabed processes; model output can be compared directly to observations of both modern and ancient sedimentary strata. [PUBLICATION ABSTRACT]