SERPENTINITE WEATHERING AND IMPLICATIONS FOR MARS. V. Tu, J. Baumeister, R. Metcalf , A. Olsen , E. Hausrath
I. INTRODUCTION IV. RESULTS V. DISCUSSION
In the search for life on Mars near-surface soil envi- SEM/EDS XRD ronments may be important habitats for life accessible Calculation of Serpentinite Dissolution Rate to future missions. Serpentinite rocks have been docu- mented on Mars, as well as other clay minerals includ- ing smectite and kaolinites . Previous studies of soils formed on serpentinites on Earth have documented the formation of extensive clays. Serpentinites are ad- ditionally of interest as habitats for life such as metha- Al-RICH RIND surface-area normalized weathering rate nogens . Here we examine weathering of serpentinites from bedrock to soil surface, as a potential route for density of the weathered material the formation of clay minerals on Mars from abundant ultrama c minerals. We additionally test for the pres- reactive surface-area Concentration vs. Depth: stochiometric coe cient ence of Fe-oxidizing bacteria in weathered serpenti- SEM images of polished weath- XRD- Preliminary results suggest the Rates have been calculated from the nite rocks. Fe-oxidizing bacteria have been previously ered rock suggest the formation presence of lizardite in parent material weathering velocity and the weath- weathering advance rate of AL-bearing secondary miner- and smectites, and Fe oxides in weath- demonstrated to aect dissolution rates of ultra-ma c ering gradient using the method of weathering gradient als on the surface. ered soils. minerals , and may produce important biosignatures. (White, 2002).
XRF
II. FIELD AREA & SAMPLE VI. CONCLUSIONS COLLECTION