A deep search for the release of volcanic gases on Mars using ground-based high-resolution infrared and submillimeter spectroscopy: Sensitive upper limits for OCS and SO2

摘要

Highlights ? We searched for SO2 and OCS in the atmosphere of Mars for two successive Mars years. ? No active release of such volcanic gases was found. ? We placed upper limits of 1.8?ppbv and 3.1?ppbv for OCS and SO2, respectively. ? Our upper limit on SO2 yields an outgassing rate of less than 156?tons/day, corresponding to a magma rate that is able to degas the SO2 of 104?kilotons/day. Abstract Recent volcanic activity has long been considered a distinct possibility that would place major constraints on the evolution of Mars’ interior. Volcanic activity would result in the outgassing of sulfur-bearing species. As part of our multi-band search for active release of volcanic gases on Mars, we looked for carbonyl sulfide (OCS) at its combination band ( ν 1 + ν 3 ) at 3.42?μ?m (2924?cm ? 1 ), and sulfur dioxide (SO2) at 346.652?GHz, in two successive Mars years during its late Northern spring and mid Northern summer seasons (Ls= 43°–144°). The targeted volcanic districts, Tharsis and Syrtis Major, were observed during the two intervals, 15?Dec.?2011 to 6?Jan.?2012 in the first year, and 23?May?2014 to 12?June?2014 in the second year using the high resolution infrared spectrometer CSHELL on the NASA Infrared Telescope Facility, and the high resolution heterodyne receiver HARP at the James C