Volatile, Isotope, and Organic Analysis of Martian Fines with the Mars Curiosity Rover

Leshin, L. A.; Mahaffy, P. R.; Webster, C. R.; Cabane, M.; Coll, P.; Conrad, P. G.; Archer, P. D., Jr.; Atreya, S. K.; Brunner, A. E.; Buch, A.; Eigenbrode, J. L.; Flesch, G. J.; Franz, H. B.; Freissinet, C.; Glavin, D. P.; McAdam, A. C.; Miller, K. E.; Ming, D. W.; Morris, R. V.; Navarro-Gonzalez, R.; Niles, P. B.; Owen, T.; Pepin, R. O.; Squyres, S.; Steele, A.; Stern, J. C.; Summons, R. E.; Sumner, D. Y.; Sutter, B.; Szopa, C.; Teinturier, S.; Trainer, M. G.; Wray, J. J.; Grotzinger, J. P.; MSL Sci Team
2013
SCIENCE
DOI
10.1126/science.1238937
Samples from the Rocknest aeolian deposit were heated to similar to 835 degrees C under helium flow and evolved gases analyzed by Curiosity's Sample Analysis at Mars instrument suite. H2O, SO2, CO2, and O-2 were the major gases released. Water abundance (1.5 to 3 weight percent) and release temperature suggest that H2O is bound within an amorphous component of the sample. Decomposition of fine-grained Fe or Mg carbonate is the likely source of much of the evolved CO2. Evolved O-2 is coincident with the release of Cl, suggesting that oxygen is produced from thermal decomposition of an oxychloride compound. Elevated delta D values are consistent with recent atmospheric exchange. Carbon isotopes indicate multiple carbon sources in the fines. Several simple organic compounds were detected, but they are not definitively martian in origin.