HR: 0830h
AN: P11B-1043    [PDF]
TI: Mapping Hydrothermal Alteration Zones on Mauna Kea Using AVIRIS Data: An Analog for Mars
AU: * Guinness, E A
EM: guinness@wunder.wustl.edu
AF: Washington University, Dept. of Earth and Planetary Sci., St Louis, MO 63130 United States
AU: Arvidson, R E
AF: Washington University, Dept. of Earth and Planetary Sci., St Louis, MO 63130 United States
AU: Jolliff, B L
AF: Washington University, Dept. of Earth and Planetary Sci., St Louis, MO 63130 United States
AU: Deal, K S
AF: Washington University, Dept. of Earth and Planetary Sci., St Louis, MO 63130 United States
AU: Seelos, F P
AF: Washington University, Dept. of Earth and Planetary Sci., St Louis, MO 63130 United States
AU: Morris, R V
AF: NASA-Johnson Space Center, Code SN, Houston, TX 77058 United States
AU: Ming, D W
AF: NASA-Johnson Space Center, Code SN, Houston, TX 77058 United States
AU: Graff, T G
AF: Arizona State University, Dept. of Geological Sci., Tempe, AZ 85287 United States
AB: Identifying and mapping areas of hydrothermal alteration on Mars are important parts of understanding the water cycle on that planet. The summit of Mauna Kea, Hawaii, provides an environment that exhibits hydrothermal alteration within a volcanic terrain that may be analogous to Mars. Hydrothermal alteration zones exposed on Mauna Kea cinder cones have been mapped using AVIRIS hyperspectral imaging data, which has 10-nm spectral band widths between 0.4 and 2.5 micrometers and a ground resolution of about 15 m. Mapped alteration minerals on Mauna Kea include kaolinite, montmorillonite, saponite, hematite, and jarosite. These altered areas have been observed on cinder cones with basal diameters from 500 m to about 1 km, with exposures of altered material being between 50 to 400 m. As a test of the likelihood that similar alteration zones will be detectable on Mars by the OMEGA spectrometer on Mars Express or the CRISM imaging spectrometer on Mars Reconnaissance Orbiter, AVIRIS data of Mauna Kea have been resampled to match spatial resolutions of these instruments and then analyzed to search for the same alteration minerals found in the full-resolution data. At the resolution of the CRISM multispectral mapping mode (200 m/pixel), most of the Mauna Kea altered zones are still identifiable even though the strength of absorption features are somewhat reduced. Even at the 300-500 m/pixel resolution expected for OMEGA observations, the larger altered zones on Mauna Kea are still discernible. Several researchers have identified regions throughout the northern and southern plains on Mars containing numerous km-sized cones that are thought to be volcanic in origin. Thus, regions on Mars containing km-sized cones would be ideal places to target with OMEGA and CRISM observations to search for hydrothermal alteration zones where fractures and mass wasting might have exposed and dispersed any altered materials, making them more detectable by OMEGA and CRISM.
DE: 5400 PLANETOLOGY: SOLID SURFACE PLANETS
DE: 5464 Remote sensing
DE: 5470 Surface materials and properties
DE: 6225 Mars
SC: Planetary Sciences [P]
MN: 2003 Fall Meeting