TY - JOUR
T1 - The first X-ray diffraction measurements on Mars
AU - Bish, David
AU - Blake, David
AU - Vaniman, David
AU - Sarrazin, Philippe
AU - Bristow, Thomas
AU - Achilles, Cherie
AU - Dera, Przemyslaw
AU - Chipera, Steve
AU - Crisp, Joy
AU - Downs, R. T.
AU - Farmer, Jack
AU - Gailhanou, Marc
AU - Ming, Doug
AU - Morookian, John Michael
AU - Morris, Richard
AU - Morrison, Shaunna
AU - Rampe, Elizabeth
AU - Treiman, Allan
AU - Yen, Albert
PY - 2014/10/10
Y1 - 2014/10/10
N2 - The Mars Science Laboratory landed in Gale crater on Mars in August 2012, and the Curiosity rover then began field studies on its drive toward Mount Sharp, a central peak made of ancient sediments. CheMin is one of ten instruments on or inside the rover, all designed to provide detailed information on the rocks, soils and atmosphere in this region. CheMin is a miniaturized X-ray diffraction/X-ray fluorescence (XRD/XRF) instrument that uses transmission geometry with an energy-discriminating CCD detector. CheMin uses onboard standards for XRD and XRF calibration, and beryl:quartz mixtures constitute the primary XRD standards. Four samples have been analysed by CheMin, namely a soil sample, two samples drilled from mudstones and a sample drilled from a sandstone. Rietveld and full-pattern analysis of the XRD data reveal a complex mineralogy, with contributions from parent igneous rocks, amorphous components and several minerals relating to aqueous alteration. In particular, the mudstone samples all contain one or more phyllosilicates consistent with alteration in liquid water. In addition to quantitative mineralogy, Rietveld refinements also provide unit-cell parameters for the major phases, which can be used to infer the chemical compositions of individual minerals and, by difference, the composition of the amorphous component.
AB - The Mars Science Laboratory landed in Gale crater on Mars in August 2012, and the Curiosity rover then began field studies on its drive toward Mount Sharp, a central peak made of ancient sediments. CheMin is one of ten instruments on or inside the rover, all designed to provide detailed information on the rocks, soils and atmosphere in this region. CheMin is a miniaturized X-ray diffraction/X-ray fluorescence (XRD/XRF) instrument that uses transmission geometry with an energy-discriminating CCD detector. CheMin uses onboard standards for XRD and XRF calibration, and beryl:quartz mixtures constitute the primary XRD standards. Four samples have been analysed by CheMin, namely a soil sample, two samples drilled from mudstones and a sample drilled from a sandstone. Rietveld and full-pattern analysis of the XRD data reveal a complex mineralogy, with contributions from parent igneous rocks, amorphous components and several minerals relating to aqueous alteration. In particular, the mudstone samples all contain one or more phyllosilicates consistent with alteration in liquid water. In addition to quantitative mineralogy, Rietveld refinements also provide unit-cell parameters for the major phases, which can be used to infer the chemical compositions of individual minerals and, by difference, the composition of the amorphous component.
KW - Curiosity rover
KW - Mars
KW - X-ray diffraction
KW - extraterrestrial mineralogy
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U2 - 10.1107/S2052252514021150
DO - 10.1107/S2052252514021150
M3 - Article
AN - SCOPUS:84941357874
SN - 2052-2525
VL - 1
SP - 514
EP - 522
JO - IUCrJ
JF - IUCrJ
ER -