Water and carbon dioxide sorption properties of natural zeolites and clay minerals at martian surface temperature and pressure conditions

摘要

The verified presence of smectites, natural zeolites, sulfates and other water-bearing minerals on the martian surface have encouraged us to study their water and CO_2 adsorption behaviour under conditions close to martian equatorial surface temperature and pressure. The results for smectites and zeolites show about 2.5-25 wt% of (partially mobile) water at low temperatures and a very low partial pressure of 0.001 mbar. Mars relevant minerals such as nontronite, montmorillonite, clinoptilolite and chabazite can adsorb water even in a more than thousandfold surplus (6 mbar) of carbon dioxide. The presence of water in equatorial latitudes might be of importance for water involved chemistry and hypothetical exobiological activity on Mars.