Show simple item record

dc.contributor.authorPelletier, Jon D.
dc.date.accessioned2018-06-13T18:44:10Z
dc.date.available2018-06-13T18:44:10Z
dc.date.issued2018-04
dc.identifier.citationPelletier, J. D. (2018). Controls on yardang development and morphology: 2. Numerical modeling. Journal of Geophysical Research: Earth Surface, 123, 723–743. https://doi.org/10.1002/2017JF004462en_US
dc.identifier.issn2169-9003
dc.identifier.doi10.1002/2017JF004462
dc.identifier.urihttp://hdl.handle.net/10150/627959
dc.description.abstractHere I present a set of mathematical modeling results, constrained by the results of the companion paper, aimed at improving our understanding of yardang development and controls on yardang morphology. The classic model for yardang development posits that yardangs evolve to an aspect ratio of approximate to 4 in order to minimize aerodynamic drag. Computational fluid dynamics model results presented here, however, demonstrate that yardangs with an aspect ratio of 4 do not minimize drag. As an alternative, I propose that yardang aspect ratios are primarily controlled by the lateral downwind expansion of wind and wind-blown sediments focused into the troughs among yardangs, which can be quantified using previous studies of wall-bounded turbulent jets. This approach predicts yardangs with aspect ratios in the range of 5 to 10, that is, similar to those of natural yardangs. In addition to aerodynamics, yardang aspect ratios are influenced by the strikes and dips of strata, as demonstrated in the companion paper. To better understand the aerodynamic and bedrock structural controls on yardang morphology, I developed a landscape evolution model that combines the physics of boundary layer flow and abrasion by eolian sediment transport with a model for the erosion of the tops and lee sides of yardangs by water-driven erosional processes. Yardang formation in the model is enhanced in substrates with greater heterogeneity (i.e., alternating strong and weak strata). Yardang morphology is controlled by the strikes and dips of strata as well as the topographic diffusivity associated with water-driven erosional processes.en_US
dc.description.sponsorshipNSF [1323148]en_US
dc.language.isoenen_US
dc.publisherAMER GEOPHYSICAL UNIONen_US
dc.relation.urlhttps://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2017JF004462en_US
dc.rights©2018. American Geophysical Union. All Rights Reserved.en_US
dc.titleControls on Yardang Development and Morphology: 2. Numerical Modelingen_US
dc.typeArticleen_US
dc.contributor.departmentUniv Arizona, Dept Geoscien_US
dc.identifier.journalJOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACEen_US
dc.description.note6 month embargo; published online: 02 April 2018en_US
dc.description.collectioninformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.en_US
dc.eprint.versionFinal published versionen_US


Files in this item

Thumbnail
Name:
Pelletier-2018-Journal_of_Geop ...
Size:
5.501Mb
Format:
PDF
Description:
Final Published version

This item appears in the following Collection(s)

Show simple item record