A faithful record of channel mouth bifurcation angles in river delta stratigraphy on Earth and Mars

This is a Preprint and has not been peer reviewed.

Downloads

Download Preprint

Supplementary Files
Authors

Robert Clyde Mahon , John B Shaw

Abstract

Which geomorphologic features of sedimentary systems persist into the stratigraphic record? In modern river deltas, channel mouth bifurcation angles have been shown to be consistent with network growth in a Laplacian flow field proximal to the channel margins. This results in a characteristic bifurcation angle of 72 . However, the persistence of this formative angle through channel evolution and preservation into the stratigraphic record remains untested. Stratigraphic river delta channel mouth bifurcations were measured using stratal slices from 3D seismic as well as Mars HiRISE orbital imagery. We find that channel mouth bifurcations interpreted from terrestrial strata exhibit a mean angle of 72.8 ± 4.1 (95% confidence interval) and those from martian strata exhibit a mean angle of 73.9 ± 6.0 . This is both consistent with theory and with observations from modern river deltas, implying the persistence of this geometry throughout network evolution and preservation, and may therefore be used as a predictive tool. The consistency between terrestrial and martian bifurcation geometry shows the generality of process between planetary systems, independent of differences in gravitational acceleration.

DOI

https://doi.org/10.31223/osf.io/9r64a

Subjects

Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy

Keywords

stratigraphy, Delta, Mars, geomorphology, surface processes

Dates

Published: 2018-03-02 07:42

Older Versions
License

CC BY Attribution 4.0 International

Add a Comment

You must log in to post a comment.


Comments

There are no comments or no comments have been made public for this article.