Detection of Silica-Rich Deposits on Mars
S. W. Squyres,1*
R. E. Arvidson,2
S. Ruff,3
R. Gellert,4
R. V. Morris,5
D. W. Ming,5
L. Crumpler,6
J. D. Farmer,3
D. J. Des Marais,7
A. Yen,8
S. M. McLennan,9
W. Calvin,10
J. F. Bell, III,1
B. C. Clark,11
A. Wang,2
T. J. McCoy,12
M. E. Schmidt,12
P. A. de Souza, Jr.13
Mineral deposits on the martian surface can elucidate ancient environmental conditions on the planet. Opaline silica deposits (as much as 91 weight percent SiO2) have been found in association with volcanic materials by the Mars rover Spirit. The deposits are present both as light-toned soils and as bedrock. We interpret these materials to have formed under hydrothermal conditions and therefore to be strong indicators of a former aqueous environment. This discovery is important for understanding the past habitability of Mars because hydrothermal environments on Earth support thriving microbial ecosystems.
1 Department of Astronomy, Space Sciences Building, Cornell University, Ithaca, NY 14853, USA.
2 Department of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130, USA.
3 School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287, USA.
4 Department of Physics, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
5 NASA Johnson Space Center, Houston, TX 77058, USA.
6 New Mexico Museum of Natural History and Science, Albuquerque, NM 87104, USA.
7 NASA Ames Research Center, Moffett Field, CA 94035, USA.
8 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
9 Department of Geosciences, State University of New York, Stony Brook, NY 11794, USA.
10 Department of Geological Sciences, University of Nevada, Reno, NV 89557, USA.
11 Lockheed Martin Corporation, Littleton, CO80127, USA.
12 Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, USA.
13 Tasmanian Information and Communication Technology Centre, Commonwealth Scientific and Industrial Research Organisation, Castray Esplanade, Hobart, TAS 7000, Australia.
* To whom correspondence should be addressed. E-mail: squyres{at}astro.cornell.edu
