A global Mars dust composition refined by the Alpha‐Particle X‐ray Spectrometer in Gale Crater. Issue 1 (9th January 2016)

• Record Type: Journal Article
• Authors: Berger, Jeff A.; Schmidt, Mariek E.; Gellert, Ralf; Campbell, John L.; King, Penelope L.; Flemming, Roberta L.; Ming, Douglas W.; Clark, Benton C.; Pradler, Irina; VanBommel, Scott J. V.; Minitti, Michelle E.; Fairén, Alberto G.; Boyd, Nicholas I.; Thompson, Lucy M.; Perrett, Glynis M.; Elliott, Beverley E.; Desouza, Elstan
• Is Part Of: Geophysical research letters. Volume 43:Issue 1(2016)
• Page Start: 67
• Page End: 75
• Publication Date: 2016-01-09
• Subjects: Mars dust -- Mars surface S/Cl -- MSL APXS -- Mars soil; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL066675
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Modern Martian dust is similar in composition to the global soil unit and bulk basaltic Mars crust, but it is enriched in S and Cl. The Alpha Particle X‐ray Spectrometer (APXS) on the Mars Science Laboratory Curiosity rover analyzed air fall dust on the science observation tray (o‐tray) in Gale Crater to determine dust oxide compositions. The o‐tray dust has the highest concentrations of SO3 and Cl measured in Mars dust (SO3 8.3%; Cl 1.1 wt %). The molar S/Cl in the dust (3.35 ± 0.34) is consistent with previous studies of Martian dust and soils (S/Cl = 3.7 ± 0.7). Fe is also elevated ~25% over average Mars soils and the bulk crust. These enrichments link air fall dust with the S‐, Cl‐, and Fe‐rich X‐ray amorphous component of Gale Crater soil. Dust and soil have the same S/Cl, constraining the surface concentrations of S and Cl on a global scale. Key Points: The composition of freshly deposited dust was determined on Mars Dust lofted on Mars today has higher S and Cl but the same S/Cl as average soil Air fall dust on Mars is compositionally similar across the planet