Martian Chlorine Chemistry: A Study of Perchlorate on the Martian Surface, Evidence of an Ongoing Formation Mechanism and Implications of a Complex Chlorine Cycle.
Abstract: The research presented herein addresses the detection of perchlorate
on Mars, evidence of perchlorate in Mars meteorite EETA 79001, determination of the
perchlorate parent salts at the Phoenix landing site, and the ongoing formation of
perchlorate from chloride minerals as well as from other oxychlorine species. The detection
of perchlorate in three samples by the Phoenix Wet Chemistry ... read moreLaboratory and the implication
of these results are discussed. The further detection of perchlorate in Mars meteorite EETA
79001 by ion chromatography and the determination of the parent salts of the perchlorate
detected at the Phoenix landing site by electrochemical analyses and ion chromatography are
detailed and the implications of the identity of the parent salts are discussed. The
possible formation pathways for martian perchlorate are then explored and a possible
mechanism for ongoing perchlorate formation on the martian surface is detailed. Perchlorate
is shown to be formed upon exposure of chloride minerals, as well as of chlorite and
chlorate salts, to current Mars relevant conditions including temperature, pressure,
ultraviolet radiation and atmospheric composition. The implications of this ongoing
perchlorate formation for the survival and detection of organics, the oxidizing nature of
the soil, formation of liquid brines and recurring slope lineae are discussed. Further
preliminary experiments have been conducted to investigate the effects of perchlorate
formation on the survival and degradation of organic compounds.
Thesis (Ph.D.)--Tufts University, 2015.
Submitted to the Dept. of Chemistry.
Advisor: Samuel Kounaves.
Committee: Arthur Utz, Jonathan Kenny, and Michael Hecht.
Keywords: Chemistry, and Planetology.read less