TY - JOUR
T1 - Near-infrared spectroscopy of lacustrine sediments in the Great Salt Lake Desert
T2 - An analog study for Martian paleolake basins
AU - Lynch, Kennda L.
AU - Horgan, Briony H.
AU - Munakata-Marr, Junko
AU - Hanley, Jennifer
AU - Schneider, Robin J.
AU - Rey, Kevin A.
AU - Spear, John R.
AU - Jackson, W. Andrew
AU - Ritter, Scott M.
N1 - Publisher Copyright:
©2015. American Geophysical Union. All Rights Reserved.
PY - 2015/3/1
Y1 - 2015/3/1
N2 - The identification and characterization of aqueous minerals within ancient lacustrine environments on Mars are a high priority for determining the past habitability of the red planet. Terrestrial analog studies are useful both for understanding the mineralogy of lacustrine sediments, how the mineralogy varies with location in a lacustrine environment, and for validating the use of certain techniques such as visible-near-infrared (VNIR) spectroscopy. In this study, sediments from the Pilot Valley paleolake basin of the Great Salt Lake desert were characterized using VNIR as an analog for Martian paleolake basins. The spectra and subsequent interpretations were then compared to mineralogical characterization by ground truth methods, including X-ray diffraction, automated scanning electron microscopy, and several geochemical analysis techniques. In general, there is good agreement between VNIR and ground truth methods on the major classes of minerals present in the lake sediments and VNIR spectra can also easily discriminate between clay-dominated and salt-dominated lacustrine terrains within the paleolake basin. However, detection of more detailed mineralogy is difficult with VNIR spectra alone as some minerals can dominate the spectra even at very low abundances. At this site, the VNIR spectra are dominated by absorption bands that are most consistent with gypsum and smectites, though the ground truth methods reveal more diverse mineral assemblages that include a variety of sulfates, primary and secondary phyllosilicates, carbonates, and chlorides. This study provides insight into the limitations regarding the use of VNIR in characterizing complex mineral assemblages inherent in lacustrine settings.
AB - The identification and characterization of aqueous minerals within ancient lacustrine environments on Mars are a high priority for determining the past habitability of the red planet. Terrestrial analog studies are useful both for understanding the mineralogy of lacustrine sediments, how the mineralogy varies with location in a lacustrine environment, and for validating the use of certain techniques such as visible-near-infrared (VNIR) spectroscopy. In this study, sediments from the Pilot Valley paleolake basin of the Great Salt Lake desert were characterized using VNIR as an analog for Martian paleolake basins. The spectra and subsequent interpretations were then compared to mineralogical characterization by ground truth methods, including X-ray diffraction, automated scanning electron microscopy, and several geochemical analysis techniques. In general, there is good agreement between VNIR and ground truth methods on the major classes of minerals present in the lake sediments and VNIR spectra can also easily discriminate between clay-dominated and salt-dominated lacustrine terrains within the paleolake basin. However, detection of more detailed mineralogy is difficult with VNIR spectra alone as some minerals can dominate the spectra even at very low abundances. At this site, the VNIR spectra are dominated by absorption bands that are most consistent with gypsum and smectites, though the ground truth methods reveal more diverse mineral assemblages that include a variety of sulfates, primary and secondary phyllosilicates, carbonates, and chlorides. This study provides insight into the limitations regarding the use of VNIR in characterizing complex mineral assemblages inherent in lacustrine settings.
KW - Mars
KW - evaporites
KW - lacustrine sediments
KW - paleolakes
KW - phyllosilicates
KW - spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=84927603353&partnerID=8YFLogxK
U2 - 10.1002/2014JE004707
DO - 10.1002/2014JE004707
M3 - Article
AN - SCOPUS:84927603353
SN - 2169-9097
VL - 120
SP - 599
EP - 623
JO - Journal of Geophysical Research: Planets
JF - Journal of Geophysical Research: Planets
IS - 3
ER -