NASA Astrobiology Institute (NAI)

1. Characterization of Aqueous Processes on Mars Through Spectral Remote Sensing

   Project Investigators: Janice Bishop

   Summary

   We are analyzing spectral data of Mars including i) CRISM images for the presence of phyllosilicates and sulfates and ii) MER Gusev crater Pancam data of the bright salty soils. This also involves characterizing the spectral properties of i) phyllosilicates and sulfates having a variety of mineral structures, and ii) altered volcanic material containing phyllosilicates and sulfates.

   Work this year on the bright salty soils found at Paso Robles and other sites in Gusev crater showed that this material is composed of the ferric minerals ferricopiapite, fibroferrite and/or ferristrunzite (Lane et al., 2008, Parente et al., 2008). Pancam multispectral visible/near-infrared (VNIR) images of Mars from Gusev crater are shown in Figures 2 and 3. Analysis of these Pancam data together with the mini-TES and Mössbauer data collected by MER enabled characterization of the minerals in the bright salty soils.

   Our work analyzing the clay minerals at Mawrth Vallis, Mars, has shown the presence of a large clay deposit that suggests long-standing water on Mars (Bishop et al., 2008). The stratigraphy of the phyllosilicates indicates a complex and interesting aqueous chemistry.

   During this year we also completed a study on alteration near Kilauea, Hawaii, where solfataric alteration of ash deposits is taking place and where orange-colored Fe-Ti-S-Si-bearing coatings are forming near vent sites on lava. We are in the process of preparing a manuscript for publication on this study.

   Astrobiology Roadmap Objectives:

   • Objective 2.1: Mars exploration

   Project Progress

   We are analyzing spectral data of Mars including i) CRISM images for the presence of phyllosilicates and sulfates and ii) MER Gusev crater Pancam data of the bright salty soils. This also involves characterizing the spectral properties of i) phyllosilicates and sulfates having a variety of mineral structures, and ii) altered volcanic material containing phyllosilicates and sulfates.

   Work this year on the bright salty soils found at Paso Robles and other sites in Gusev crater showed that this material is composed of the ferric minerals ferricopiapite, fibroferrite and/or ferristrunzite (Lane et al., 2008, Parente et al., 2008). Pancam multispectral visible/near-infrared (VNIR) images of Mars from Gusev crater are shown in Figures 2 and 3. Analysis of these Pancam data together with the mini-TES and Mössbauer data collected by MER enabled characterization of the minerals in the bright salty soils.

   Our work analyzing the clay minerals at Mawrth Vallis, Mars, has shown the presence of a large clay deposit that suggests long-standing water on Mars (Bishop et al., 2008). The stratigraphy of the phyllosilicates indicates a complex and interesting aqueous chemistry.

   During this year we also completed a study on alteration near Kilauea, Hawaii, where solfataric alteration of ash deposits is taking place and where orange-colored Fe-Ti-S-Si-bearing coatings are forming near vent sites on lava. We are in the process of preparing a manuscript for publication on this study.

   
   

   CRISM spectra from Mawrth Vallis image HRL000043EC (and the overlapping image FRT0000863E) compared to lab spectra of phyllosilicates and hydrated silica-bearing materials.

   
   

   Map of clay minerals in CRISM image draped over MOLA terrain with 20X vertical enhancement showing Fe/Mg-smectite (orange/red), Al-phyllosilicate and hydrated silica (blue) and Fe2+-bearing phases (yellow/green).

   Mission Involvement

   MRO

   CRISM data analysis: Identification of minerals associated with aqueous processes in CRISM images of Mars. Specifically, phyllosilicates are under study at Mawrth Vallis and Libya Montes, and sulfates are under study at Juventae Chasma.

   MER

   Pancam data analysis: Identification of sulfate and phosphate minerals in the bright region salty soils at Paso Robles, Arad and Tyrone.

Publications

Bishop, J.L., Noe Dobrea, E.Z., McKeown, N.K., Parente, M., Ehlmann, B.L., Michalski, J.R., Milliken, R.E., Poulet, F., Swayze, G.A., Mustard, J.F., Murchie, S.L. & Bibring, J.-.  (2008).  Phyllosilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars.  Science:in press.

Lane, M.D., Bishop, J.L., Dyar, M.D., King, P.L., Parente, M. & Hyde, B.C.  (2008).  Mineralogy of the Paso Robles Soils on Mars.  American Mineralogist, 93:728-739.

Parente, M., Bishop, J.L. & Bell, J.F.  (2008).  Spectral unmixing and anomaly detection for mineral identification in Pancam images of Gusev soils.  Icarus:in review.