The origin of alteration “orangettes” in Dhofar 019: Implications for the age and aqueous history of the shergottites.OPEN ACCESS 

· by · in , , , , ,

Hallis, L. J., Kemppinen, L., Lee, M. R. and Taylor, L. A.

Meteorit Planet Sci. doi:10.1111/maps.12987

LINK (OPEN ACCESS)
PDF (OPEN ACCESS)

“The shergottites are the largest group of Martian meteorites, and the only group that has not been found to contain definitive evidence of Martian aqueous alteration. Given recent reports of current liquid water at the surface of Mars, this study aimed to investigate in detail the possibility of Martian phyllosilicate within shergottite Dhofar 019. Optical and scanning electron microscopy, followed by transmission electron microscopy, confirmed the presence of alteration orangettes, with a layered structure consisting of poorly ordered Mg-phyllosilicate and calcite. These investigations identified maskelynite dissolution, followed by Mg-phyllosilicate and calcite deposition within the dissolution pits, as the method of orangette production. The presence of celestine within the orangette layers, the absence of shock dislocation features within calcite, and the Mg-rich nature of the phyllosilicate, all indicate a terrestrial origin for these features on Dhofar 019.”

Related posts (automatically generated):

  1. Crystallization history of enriched shergottites from Fe and Mg isotope fractionation in olivine megacrysts
  2. The Northwest Africa (NWA) 5790 meteorite: A mesostasis-rich nakhlite with little or no Martian aqueous alteration (OPEN ACCESS)
  3. Hapke mixture modeling applied to VNIR spectra of mafic mineral mixtures and shergottites: Implications for quantitative analysis of satellite dataOPEN ACCESS 
  4. Terrestrial Alteration Mineral Assemblages in the NWA 10416 Olivine Phyric Shergottite
  5. Petrology and geochemistry of olivine‐phyric shergottites LAR 12095 and LAR 12240: Implications for their petrogenetic history on MarsOPEN ACCESS 
  6. Bright carbonate veins on asteroid (101955) Bennu: Implications for aqueous alteration history
  7. Siderophile and chalcophile element abundances in shergottites: Implications for Martian core formation
  8. Petrographic controls on baddeleyite occurrence in a suite of eight basaltic shergottites
  9. Indigenous Carbon-rich Matter Associated with Unusual Aqueous Alteration Features in Nakhla: Complex Formation and Preservation HistoryOPEN ACCESS 
  10. Petrogenesis of basaltic shergottite Northwest Africa 8657: Implications for fO2 correlations and element redistribution during shock melting in shergottites
Tags: , , , , , , , ,