A new shergottite martian meteorite analog system (SAS) for alteration experiments

Abstract

Martian rocky material available on Earth has been so far composed of meteorites and is limited in terms of mass and number. This restricted amount directly impairs the possibility to perform destructive analyses and experiments requiring large mass of sample, such as alteration and hydrothermal experiments. One of the main intents of the current Mars Sample Return (MSR) mission is to bring rock samples from Mars to Earth in the next 10 years. While we will have a geological context for the samples, the total mass that will be collected will also be limited. It is thus crucial to seek analogs of martian rocks, not suffering from this limitation while bearing specific martian properties required by the planned experiments.

To overcome this problem in the frame of alteration and hydrothermal experiments, we have built a flexible powder analog system to mimic a typical non-altered shergottite from a chemical and mineralogical perspective. To do so, we have selected the six main mineral phases in weight percentage present in shergottites. For each phase we selected multiple pure terrestrial mineral powders chosen for their chemistry close to their shergottite counterparts. As these mineral phases come from only three different relatively easy access locations, the assemblage is virtually unlimited.

From the Shergottite Analog System (SAS), the Shergottite Sample Powder (SSP)-1 analog has been created to focus on serpentinization and abiotic methane formation experiments under martian conditions. The SAS could also be used to create analogs of Oxia Planum, Gale Crater, or Jezero Crater, and to test possible detection interferences and to determine the sensitivity of multiple analytic techniques by varying the selected phases and their proportions.