title: Morphology and composition of the surface of Mars: Mars Odyssey THEMIS results.
abstract: The Thermal Emission Imaging System (THEMIS) on Mars Odyssey has produced infrared to visible wavelength images of the martian surface that show lithologically distinct layers with variable thickness, implying temporal changes in the processes or environments during or after their formation. Kilometer-scale exposures of bedrock are observed; elsewhere airfall dust completely mantles the surface over thousands of square kilometers. Mars has compositional variations at 100-meter scales, for example, an exposure of olivine-rich basalt in the walls of Ganges Chasma. Thermally distinct ejecta facies occur around some craters with variations associated with crater age. Polar observations have identified temporal patches of water frost in the north polar cap. No thermal signatures associated with endogenic heat sources have been identified.
authors.affiliation: Department of Geological Sciences, Arizona State University, Tempe, AZ 85287-6305, USA. phil.christensen@asu.edu
authors.forename: Philip R
authors.initials: PR
authors.lastname: Christensen
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Bandfield
authors.forename: James F
authors.initials: JF
authors.lastname: Bell
authors.forename: Noel
authors.initials: N
authors.lastname: Gorelick
authors.forename: Victoria E
authors.initials: VE
authors.lastname: Hamilton
authors.forename: Anton
authors.initials: A
authors.lastname: Ivanov
authors.forename: Bruce M
authors.initials: BM
authors.lastname: Jakosky
authors.forename: Hugh H
authors.initials: HH
authors.lastname: Kieffer
authors.forename: Melissa D
authors.initials: MD
authors.lastname: Lane
authors.forename: Michael C
authors.initials: MC
authors.lastname: Malin
authors.forename: Timothy
authors.initials: T
authors.lastname: McConnochie
authors.forename: Alfred S
authors.initials: AS
authors.lastname: McEwen
authors.forename: Harry Y
authors.initials: HY
authors.lastname: McSween
authors.forename: Greg L
authors.initials: GL
authors.lastname: Mehall
authors.forename: Jeffery E
authors.initials: JE
authors.lastname: Moersch
authors.forename: Kenneth H
authors.initials: KH
authors.lastname: Nealson
authors.forename: James W
authors.initials: JW
authors.lastname: Rice
authors.forename: Mark I
authors.initials: MI
authors.lastname: Richardson
authors.forename: Steven W
authors.initials: SW
authors.lastname: Ruff
authors.forename: Michael D
authors.initials: MD
authors.lastname: Smith
authors.forename: Timothy N
authors.initials: TN
authors.lastname: Titus
authors.forename: Michael B
authors.initials: MB
authors.lastname: Wyatt
mesh_terms: D002245:Carbon Dioxide; D005118:Extraterrestrial Environment; D019015:Geologic Sediments; D055593:Geological Phenomena; D005844:Geology; D018535:Mars; D012621:Seasons; D013696:Temperature; D014867:Water
chemical_list: D014867:Water; D002245:Carbon Dioxide