CaltechAUTHORS
Published December 2017 | Version Published
Journal Article Open

Chemistry, Mineralogy, and Grain Properties at Namib and High Dunes, Bagnold Dune Field, Gale Crater, Mars: A Synthesis of Curiosity Rover Observations

Creators

  • 1. ROR icon California Institute of Technology
  • 2. ROR icon Jet Propulsion Lab
  • 3. ROR icon Malin Space Science Systems (United States)
  • 4. ROR icon Johnson Space Center
  • 5. ROR icon University of Arizona
  • 6. ROR icon Space Research Institute
  • 7. ROR icon Cornell University
  • 8. ROR icon Washington University in St. Louis
  • 9. ROR icon Ames Research Center
  • 10. ROR icon Johns Hopkins University Applied Physics Laboratory
  • 11. ROR icon Goddard Space Flight Center
  • 12. ROR icon Research Institute in Astrophysics and Planetology
  • 13. ROR icon Arizona State University
  • 14. ROR icon University of Guelph
  • 15. ROR icon Southwest Research Institute
  • 16. ROR icon Observatoire Midi-Pyrénées
  • 17. ROR icon University of New Brunswick
  • 18. ROR icon University of Hawaii at Manoa
  • 19. ROR icon German Aerospace Center
  • 20. ROR icon Stony Brook University
  • 21. ROR icon Planetary Science Institute
  • 22. ROR icon Los Alamos National Laboratory

Abstract

The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45–500 μm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion. Nevertheless, Bagnold mineralogy and Rocknest mineralogy are similar with plagioclase, olivine, and pyroxenes in similar proportions comprising >90% of crystalline phases, along with a substantial amorphous component (35% ± 15%). Yet Bagnold and Rocknest bulk chemistry differ. Bagnold sands are Si enriched relative to other soils at Gale crater, and H₂O, S, and Cl are lower relative to all previously measured Martian soils and most Gale crater rocks. Mg, Ni, Fe, and Mn are enriched in the coarse-sieved fraction of Bagnold sands, corroborated by visible/near-infrared spectra that suggest enrichment of olivine. Collectively, patterns in major element chemistry and volatile release data indicate two distinctive volatile reservoirs in Martian soils: (1) amorphous components in the sand-sized fraction (represented by Bagnold) that are Si-enriched, hydroxylated alteration products and/or H₂O- or OH-bearing impact or volcanic glasses and (2) amorphous components in the fine fraction (<40 μm; represented by Rocknest and other bright soils) that are Fe, S, and Cl enriched with low Si and adsorbed and structural H₂O.

Additional Information

© 2017 The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. Received 16 JAN 2017; Accepted 19 MAY 2017; Accepted article online 12 JUN 2017; Published online 7 DEC 2017. We thank the MSL science, operations, engineering, and management teams for the strategic and tactical planning, execution, and data archiving for the Bagnold dune campaign. We especially thank members, past and present, of the aeolian group for their work to collect this coordinated data set. Special acknowledgement goes to Deirdra Fey and Michael Ravine for assistance with MAHLI image product tracking, processing, and analysis and Jason Van Beek and the Mastcam team at Malin Space Science Systems for their work to acquire images free of shadows and for mosaic production. Thanks to Bob Deen and the JPL OPGS staff for creation of Navcam mosaics. Thanks to Mikki Osterloo and an anonymous reviewer for their comments, which helped us improve this manuscript. B.L.E., A.A.F., R.E.A., V.E.H., and J.R.J. acknowledge the MSL Participating Scientist Program for support. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. All data used in this study are available online at the NASA Planetary Data System Geosciences Node and can be readily accessed by sol using the Analyst's Notebook tool.

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Additional details

Identifiers

PMCID
PMC5815393
Eprint ID
78119
DOI
10.1002/2017JE005267
Resolver ID
CaltechAUTHORS:20170612-135954084

Funding

NASA/JPL/Caltech

Dates

Created
2017-06-19
Created from EPrint's datestamp field
Updated
2022-11-29
Created from EPrint's last_modified field

Caltech Custom Metadata

Caltech groups
Division of Geological and Planetary Sciences (GPS)