Other
Scientific paper
Jul 1998
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998icar..134....1m&link_type=abstract
Icarus, Volume 134, Issue 1, pp. 1-10.
Other
22
Scientific paper
The spectral properties of the Olympus-Amazonis region of Mars were reproduced using laboratory mixtures of palagonitic tephra and goldenrod pigments, which are blends of well-crystalline hematite and goethite. Laboratory spectra for pure pigments and mixtures were obtained at ~140 and ~305 K to bracket the temperature range of the martian surface. The best fit to the martian surface spectrum was obtained with a mixture of palagonitic tephra and 2.5% BLS12, a goldenrod pigment with 44% of its iron atoms associated with hematite and 56% with goethite (determined from Mossbauer spectroscopy). Although goethite is the major phase, the positions of reflectivity maximum and minimum near 750 and 860 nm, respectively, are determined by the hematite component at both temperatures. Spectrally, the presence of goethite is recognized by increased reflectivity between ~400 and 550 nm and, particularly at low temperatures, lowered reflectivity between ~1000 and 1300 nm compared to spectra of mixtures containing only hematite. Although the presence of goethite is consistent with the martian spectrum, the presence of the mineralogy is equivocal because other ferric-bearing phases (e.g., maghemite, lepidocrocite, akaganeite, schwertmannite, jarosite, and nontronite) have similar spectral characteristics, making definitive identification difficult. Thus, our results show that spectral data for Olympus-Amazonis, which are hematitic based on positions of spectral features, permit the presence of comparable proportions of other ferric-bearing phases. Weathering products in addition to hematite, such as goethite from oxidative and hydrolytic weathering or jarosite and/or schwertmannite from acid-sulfate weathering, may be present but spectrally masked by hematite.
Golden D. C.
Morris Richard V.
No associations
LandOfFree
Goldenrod Pigments and the Occurrence of Hematite and Possibly Goethite in the Olympus-Amazonis Region of Mars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Goldenrod Pigments and the Occurrence of Hematite and Possibly Goethite in the Olympus-Amazonis Region of Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Goldenrod Pigments and the Occurrence of Hematite and Possibly Goethite in the Olympus-Amazonis Region of Mars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1267363