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Spectral, mineralogical, and geochemical variations across Home Plate, Gusev Crater, Mars indicate high and low temperature alteration
journal contribution
posted on 2023-05-17, 11:39 authored by Schmidt, ME, Farrand, WH, Johnson, JR, Schroder, C, Hurowitz, JA, McCoy, TJ, Ruff, SW, Arvidson, RE, Marais, DJ, Lewis, KW, Ming, DW, Squyres, SW, de Souza Jr, PAOver the last ~3 years in Gusev Crater, Mars, the Spirit rover observed coherent variations in color, mineralogy, and geochemistry across Home Plate, an ~80 m-diameter outcrop of basaltic tephra. Observations of Home Plate from orbit and from the summit of Husband Hill reveal clear differences in visible/near-infrared (VNIR) colors between its eastern and western regions that are consistent with mineralogical compositions indicated by Mössbauer spectrometer (MB) and by Miniature Thermal Emission Spectrometer (Mini-TES). Pyroxene and magnetite dominate the east side, while olivine, nanophase Fe oxide (npOx) and glass are more abundant on the western side. Alpha Particle X-Ray Spectrometer (APXS) observations reveal that eastern Home Plate has higher Si/Mg, Al, Zn, Ni, and K, while Cl and Br are higher in the west. We propose that these variations are the result of two distinct alteration regimes that may or may not be temporally related: a localized, higher temperature recrystallization and alteration of the east side of Home Plate and lower temperature alteration of the western side that produced npOx.
History
Publication title
Earth and Planetary Science LettersVolume
281Issue
3-4Pagination
258-266ISSN
0012-821XDepartment/School
School of Information and Communication TechnologyPublisher
Elsevier Science BvPlace of publication
Po Box 211, Amsterdam, Netherlands, 1000 AeRights statement
Copyright 2009 ElsevierRepository Status
- Restricted