ChemCam results from the Shaler Outcrop in Gale Crater, Mars

Ryan Bradley Anderson; L. Edgar; J.C. Bridges; A. Williams; J. Williams; A. Ollila; O. Forni; N. Mangold; N. Lanza; V. Sautter; S. Gupta; D. Blaney; B. Clark; G. Clegg; G. Dromart; O. Gasnault; J. Lasue; S. Le Mouélic; Richard Léveillé; E. Lewin; K. Lewis; S. Maurice; Marion Nachon; H. Newsom; D. Vaniman; R. C. Wiens

USGS · 70093641

ChemCam results from the Shaler Outcrop in Gale Crater, Mars

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Abstract

The "Shaler" outcrop in Gale crater is approximately 0.7 m thick and >20 m long, and exhibits multiple well-exposed platy and cross-stratified facies [1] interpreted to be primarily fluvial sandstone deposits. The outcrop is a part of the upper Glenelg member in the Yellowknife Bay (YKB) stratigraphic section [2]. Curiosity first encountered the "Shaler" outcrop on sol 121 of the mission, and returned to the outcrop on sols 309- 324. The rugged nature of the outcrop and short time available for analysis limited opportunities for contact science, but ChemCam’s ability to remotely collect compositional and textural observations resulted in a large data set from Shaler. ChemCam conducted analyses of 29 non-soil targets at Shaler, 26 of which used laser-induced breakdown spectroscopy (LIBS) for a total of 9,180 spectra. Three observations used only the remote micro-imager (RMI). Each of the 26 LIBS targets were analyzed at between 5 and 25 points, providing a measure of the target homogeneity and in some cases transecting fine strata.

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Ryan Bradley Anderson, L. Edgar, J.C. Bridges, A. Williams, J. Williams, A. Ollila, O. Forni, N. Mangold, N. Lanza, V. Sautter, S. Gupta, D. Blaney, B. Clark, G. Clegg, G. Dromart, O. Gasnault, J. Lasue, S. Le Mouélic, Richard Léveillé, E. Lewin, K. Lewis, S. Maurice, Marion Nachon, H. Newsom, D. Vaniman, R. C. Wiens. 2014. ChemCam results from the Shaler Outcrop in Gale Crater, Mars. https://pubs.usgs.gov/publication/70093641

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