A Caltech Library Service

Bagnold Dunes campaign Phase 2: Visible/near‐infrared reflectance spectroscopy of longitudinal ripple sands

Johnson, Jeffrey R. and Bell, James F., III and Bender, Steve and Cloutis, Edward and Ehlmann, Bethany and Fraeman, Abigail and Gasnault, Olivier and Maurice, Sylvestre and Pinet, Patrick and Thompson, Lucy and Wellington, Danika and Wiens, Roger C. (2018) Bagnold Dunes campaign Phase 2: Visible/near‐infrared reflectance spectroscopy of longitudinal ripple sands. Geophysical Research Letters, 45 (18). pp. 9480-9487. ISSN 0094-8276. doi:10.1029/2018GL079025.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Accepted Version
See Usage Policy.

[img] MS Word - Supplemental Material
See Usage Policy.


Use this Persistent URL to link to this item:


As part of the Phase 2 Bagnold Dune campaign at Gale Crater, Mars, constraints on the geochemistry, mineralogy, and oxidation state of pristine and disturbed linear sand ripples were made using visible/near‐infrared spectral observations for comparison to Phase 1 spectra of the barchan dunes to the north. Spectra acquired by the ChemCam and Mastcam instruments (400–1,000 nm) at four Phase 2 locations revealed similar overall spectral trends between the two regions, but most Phase 2 sands were redder in the visible wavelengths. The majority of targets exhibited lower red/infrared ratios, higher ~530‐nm band depths, and higher red/blue ratios than Phase 1 samples, suggesting a greater proportion of redder, fine‐grained, ferric sands in Phase 2 samples. This is consistent with the slightly greater proportion of hematite in Phase 2 samples as determined from CheMin analyses of the Ogunquit sands, which may reflect contamination from the surrounding hematite‐bearing Murray formation bedrock.

Item Type:Article
Related URLs:
URLURL TypeDescription
Johnson, Jeffrey R.0000-0002-5586-4901
Bell, James F., III0000-0002-2006-4074
Cloutis, Edward0000-0001-7301-0929
Ehlmann, Bethany0000-0002-2745-3240
Fraeman, Abigail0000-0003-4017-5158
Gasnault, Olivier0000-0002-6979-9012
Pinet, Patrick0000-0002-1933-5631
Thompson, Lucy0000-0002-5444-952X
Wiens, Roger C.0000-0002-3409-7344
Additional Information:© 2018 American Geophysical Union. Received 31 MAY 2018; Accepted 13 JUL 2018; Accepted article online 23 JUL 2018; Published online 27 SEP 2018. This work was funded by the NASA Mars Science Laboratory Participating Scientist program through the Jet Propulsion Laboratory (contracts 1350588 and 1546033). A portion of this research was carried out at JPL, under a contract with NASA. The U.S. portion of ChemCam and MSL rover operations was funded by NASA's Mars Exploration Program. The French contribution to MSL is supported by CNES. The authors thank the operations teams involved in acquiring these data sets and W. Farrand and an anonymous reviewer for their helpful comments. Original data that underlie the conclusions presented in this manuscript can be found on the NASA Planetary Data System and/or in the relevant references cited. The authors fondly recall the dedicated efforts toward the Bagnold Dune campaigns by our late colleague Nathan Bridges.
Group:Astronomy Department
Funding AgencyGrant Number
Centre National d'Études Spatiales (CNES)UNSPECIFIED
Issue or Number:18
Record Number:CaltechAUTHORS:20180724-081744906
Persistent URL:
Official Citation:Johnson, J. R., Bell, J. F., III, Bender, S., Cloutis, E., Ehlmann, B., Fraeman, A., et al. (2018). Bagnold Dunes campaign phase 2: Visible/near‐infrared reflectance spectroscopy of longitudinal ripple sands. Geophysical Research Letters, 45, 9480–9487.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:88152
Deposited By: Tony Diaz
Deposited On:24 Jul 2018 16:21
Last Modified:16 Nov 2021 00:24

Repository Staff Only: item control page