Mapping and characterization of small-scale aeolian structures on Mars: An example from the MSL landing site in Gale Crater

Abstract

A new set of methodologies, which allow a simple and fast mapping and characterization of small-scale aeolian structures on Mars is introduced in this work. We follow an object-based approach in which the bedform crestlines are automatically mapped and characterized.From the methodology validation, we conclude that the quality of the obtained results is comparable with human-produced photointerpretations. We show that the accuracy associated with the measurement of mean trends from the automatically mapped patterns is less than 10º.Through the analysis of two areas located near the MSL landing site in Gale Crater, we explore some of the possibilities that the automatic mapping technique enables. Namely, for multitemporal surveys and ripple pattern analysis.We demonstrate how the mapped ripple patterns can be used to assess local wind orientations, and we analyze some examples that illustrate the diversity of wavelength spatial distributions that can be found on Mars. We try to relate these pattern wavelength variations with the possible local influence of granulometry and wind shear velocity. HighlightsWe introduce a set of new tools for analyzing small-scale aeolian bedforms on MarsWe evaluate the accuracy of the new mapping methodologies Several examples of possible applications are given Contrasting ripple wavelength spatial distributions are described in Gale Crater

Large wind ripples on Mars: A record of atmospheric evolution

“…S4). It was shown that, in places, the wavelength of the large martian ripples may weakly increase or decrease upslope due to local variations in grain size or wind speed (57), although no consistent increase in height and wavelength upslope is observed, contrary to terrestrial compound dunes (43). Thus, the large martian ripples are distinct from compound dunes.…”

Dune‐like dynamic of Martian Aeolian large ripples

“…The COSI-Corr displacement maps are further improved by removing jitter artifacts ( Figure S2). We then used the Object-based Ripple Analysis technique [Vaz and Silvestro, 2014] to characterize the directional distribution of the LRs, evaluate their spatial distribution and correlate bed form pattern characteristics with migration rates and morphometric settings [Vaz and Silvestro, 2014;Vaz et al, 2015] ( Figure S3).…”

Introduction to the Planetary Dunes special issue, and the aeolian career of Ronald Greeley

“…Yizhaq et al (2014) analyzed sand ripples at Eagle crater imaged by the Opportunity rover, and by coupling a numerical model for saltation with a dynamic ripple model, they conclude that the fine-grained ripples developed below the fluid threshold, consistent with the presence of substantial hysteresis in martian saltation. Finally, Vaz and Silvestro (2014) use a new set of analysis tools to characterize small-scale aeolian structures in the vicinity of the Curiosity landing site in Gale crater.…”