HR: 0830h
AN: P21B-0047    [PDF]
TI: Investigations of Hematite Deposits in Valles Marineris
AU: * Knudson, A T
EM: aknudson@asu.edu
AF: Arizona State University, Geological Sciences Box 876305, Tempe, AZ 85287-6305 United States
AU: Christensen, P R
EM: Phil.Christensen@asu.edu
AF: Arizona State University, Geological Sciences Box 876305, Tempe, AZ 85287-6305 United States
AB: Gray, crystalline hematite deposits have been identified using Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) data at three areas of Mars: Meridiani Planum, Aram Chaos, and the Valles Marineris system. Detailed studies of the deposits in Meridiani Planum and Aram Chaos reveal that the hematite occurs in coherent, in-place stratigraphic units. In contrast, the Valles Marineris occurrences are small (5 - 35 km) and scattered throughout the canyon system. The largest hematite deposits are in Ophir and Candor Chasma, where hematite appears to be associated with dark materials near or within the interior layered deposits of the canyon and may represent erosional remnants or in-place units within the layered deposits. A variety of different formational processes have been proposed for these layered deposits, many of which involve liquid water. However, little work has been done to date on the context of the hematite in this locality and the relationship with the layered deposits. This study investigates the details of the hematite occurrences in Valles Marineris, re-mapping hematite occurrence at TES pixel resolution and incorporating multiple datasets to further investigate and interpret the formation, compositional relationships, and history of these deposits. Data from the Mars Odyssey Thermal Emission Imaging System (THEMIS), the MGS Mars Orbiter Camera (MOC), and the MGS Mars Orbiter Laser Altimeter (MOLA) are used along with TES data to map the compositional, thermophysical, and geomorphic context of the hematite deposits throughout the chasma system. Numerous small, isolated occurrences are investigated along with the larger deposits in Ophir and Candor Chasma in order to determine whether the deposits share common origins or represent distinct geologic events.
DE: 5410 Composition
DE: 5415 Erosion and weathering
DE: 5464 Remote sensing
DE: 5470 Surface materials and properties
SC: Planetary Sciences [P]
MN: 2003 Fall Meeting