DOI: 10.5061/dryad.r2280gbmd
title: Controls on Preservation of Fluvial Cross Strata in the Deposition-dominated Regime

description: Migrating bedforms (ripples, dunes) in rivers are preserved as
 cross-stratified sedimentary structures—fluvial cross strata— that are
 abundant in the rock record on Earth and Mars. Our understanding of
 bedform preservation is largely based on steady-state flow conditions,
 which rarely occur in rivers. In natural rivers, multiple scales of
 bedforms evolve simultaneously (e.g., dunes, bars) leading to
 spatially-varying flow conditions; however, our understanding of the
 influence of co-evolution of multiple bedform scales on preservation of
 cross strata is limited. To address this, we simulated multi-scale bedform
 evolution in an experimental channel and characterized the controls on
 cross-strata preservation under deposition-dominated conditions.
   The data herein accompanies the manuscript “Controls on
 Preservation of Fluvial Cross-strata in the Deposition-dominated Regime ”
 by Debsmita Das, Vamsi Ganti, and Arjan Reesink. In this manuscript, we
 conducted a physical flume experiment of superimposed bedform evolution on
 a large host bedform, analogous to a bar, under constant flow discharge
 rates. We collected high resolution bathymetric data of bedform evolution
 for 300 hours, attached herein, and used it to quantify superimposed
 bedform geometry as well as set thickness statistics from constructed
 stratigraphy. Additionally, we quantified aggradation rates over the host
 bedform. We show that superimposed bedform dimensions and celerity decline
 along the host-bedform lee slope due to spatial gradients in sediment
 transport. This leads to localized bed aggradation, creating a
 deposition-dominated regime with high sedimentation rates. We
 find that the preservation ratio of cross sets is primarily controlled by
 the local bedform climb angle and that the coefficient of variation of set
 thickness is consistently low in a deposition-dominated regime. Our
 results demonstrate that fluvial morphodynamic hierarchy is a fundamental
 determinant of sedimentary strata.
description: # Controls on Preservation of Fluvial Cross Strata in the
 Deposition-dominated Regime
 [https://doi.org/10.5061/dryad.r2280gbmd](https://doi.org/10.5061/dryad.r2280gbmd) The data folder consists of 800 scans of bed topography, raw and filtered, over the study section collected over 300 hours as .mat files. ## Description of the data and file structure ### `Scan.mat` This mat file contains three variables: * *X* -vector representing coordinates in the longitudinal or downstream direction along the study section going from 1 to 4501 mm. * *Y* -vector representing coordinates in the lateral or cross-stream direction along the study section going from 1 to 751 mm. * *Z* - 2-dimensional matrix containing bed elevation scans used for computing bedform geometry and kinematics, and constructing cross-strata. Within Z, the first and second dimensions indicate represent bed elevation in longitudinal and lateral directions, respectively. All those .mat files have been zipped together into the `Scan.zip` archive. ### `ScanFiltered.mat` This mat file contains three variables: * *X* -vector representing coordinates in the longitudinal or downstream direction along the study section going from 1 to 4501 mm. * *Y*-vector representing coordinates in the lateral or cross-stream direction along the study section going from 1 to 751 mm. * *ZClean* - 2-dimensional matrix containing processed bed elevation scans used for computing bedform geometry and kinematics, and constructing cross-strata. Within Zclean, the first and second dimensions indicate represent bed elevation in longitudinal and lateral directions, respectively. All those .mat files have been zipped together into the `ScanFiltered.zip` archive.