¹L. M. Thompson,¹J. G. Spray,¹C. O’Connell-Cooper,²J. A. Berger,³A. Yen,⁴R. Gellert,⁴N. Boyd,⁴M. A. McCraig,⁵S. J. VanBommel
Journal of Geophysical Research (Planets) (in Press) Link to Article [https://doi.org/10.1029/2021JE007178]
¹Planetary and Space Science Centre, University of New Brunswick, Fredericton, Canada
²NASA Johnson Space Center, Houston, USA
³Jet Propulsion Laboratory, California Institute of Technology, Pasadena, USA
⁴Department of Physics, University of Guelph, Ontario, Canada
⁵Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, USA
Published by arrangement with John Wiley & Sons

Chemical data acquired by Curiosity’s Alpha Particle X-ray Spectrometer (APXS) during examination of the contact between the upper Mount Sharp group and overlying Stimson formation sandstones at the Greenheugh pediment reveal compositional similarities to rocks encountered earlier in the mission. Mount Sharp group strata encountered below the Basal Siccar Point group unconformity at the base and top of the section, separated by >300 m in elevation, have distinct and related compositions. This indicates enhanced post-depositional fluid flow and alteration focused along this contact. Sandstone targets exposed immediately above the unconformity have basaltic compositions consistent with previously encountered eolian Stimson formation sandstones, except at the contact, where they show the addition of S. Resistant sandstone outcrops above the contact have higher K, Mn and Na and lower Ni concentrations that primarily reflect changes in provenance. They are compositionally related to cap rock float blocks encountered as Curiosity climbed through the Mount Sharp group, and Bradbury group sandstone outcrops. The higher K, pediment sandstones are interpreted to have a similar provenance to some Bradbury group sandstones, further evidence for widespread, alkaline source rock within and/or in the vicinity of Gale crater. The Bradbury and Siccar Point groups may both be younger than the Mount Sharp group. Alternatively, an alkaline source area in and around Gale crater has been eroded by both water and wind at different times (both before and after deposition of the Mount Sharp group), during the evolution of the crater and its infill.

¹Levent Karacasulu,²David Karl,²Aleksander Gurlo,¹Cekdar Vakifahmetoglu
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2022.115270]
¹Department of Materials Science and Engineering, Izmir Institute of Technology, Urla, 35430 Izmir, Turkey
²Technische Universitaet Berlin, Institute of Materials Science and Technology, Chair of Advanced Ceramic Materials, Straße des 17. Juni 135, 10623 Berlin, Germany
Copyright Elsevier

Mars regolith simulant (MGS-1) was densified for the first time via a cold sintering process (CSP) as a novel in-situ resource utilization (ISRU) concept. The technique comprises the utilization of NaOH solution as a liquid media during the densification of simulant powder with <100 μm particle size. In as short as 30 min, with the increase in the NaOH concentration (from 3 M to 10 M) and processing temperature (from 150 °C to 250 °C), the relative densities of the regolith compacts and the mechanical properties were enhanced. The artifacts produced with Mars regolith simulant powder at 250 °C using 10 M NaOH solution yielded a relative density of around 88% and compressive strength reaching ~45 MPa.