Chemical variations in Yellowknife Bay formation sedimentary rocks analyzed by ChemCam on board the Curiosity rover on Mars

Chemical variations in Yellowknife Bay formation sedimentary rocks analyzed by ChemCam on board the Curiosity rover on Mars. Mangold, N., Forni, O., Dromart, G., Stack, K., Wiens, R. C., Gasnault, O., Sumner, D. Y., Nachon, M., Meslin, P., Anderson, R. B., Barraclough, B., Bell, J. F., Berger, G., Blaney, D. L., Bridges, J. C., Calef, F., Clark, B., Clegg, S. M., Cousin, A., Edgar, L., Edgett, K., Ehlmann, B., Fabre, C., Fisk, M., Grotzinger, J., Gupta, S., Herkenhoff, K. E., Hurowitz, J., Johnson, J. R., Kah, L. C., Lanza, N., Lasue, J., Le Mouélic, S., Léveillé, R., Lewin, E., Malin, M., McLennan, S., Maurice, S., Melikechi, N., Mezzacappa, A., Milliken, R., Newsom, H., Ollila, A., Rowland, S. K., Sautter, V., Schmidt, M., Schröder, S., d'Uston , C., Vaniman, D., & Williams, R. Journal of Geophysical Research: Planets, 120(3):2014JE004681, March, 2015.

Paper doi abstract bibtex

The Yellowknife Bay formation represents a \textasciitilde5 m thick stratigraphic section of lithified fluvial and lacustrine sediments analyzed by the Curiosity rover in Gale crater, Mars. Previous works have mainly focused on the mudstones that were drilled by the rover at two locations. The present study focuses on the sedimentary rocks stratigraphically above the mudstones by studying their chemical variations in parallel with rock textures. Results show that differences in composition correlate with textures and both manifest subtle but significant variations through the stratigraphic column. Though the chemistry of the sediments does not vary much in the lower part of the stratigraphy, the variations in alkali elements indicate variations in the source material and/or physical sorting, as shown by the identification of alkali feldspars. The sandstones contain similar relative proportions of hydrogen to the mudstones below, suggesting the presence of hydrous minerals that may have contributed to their cementation. Slight variations in magnesium correlate with changes in textures suggesting that diagenesis through cementation and dissolution modified the initial rock composition and texture simultaneously. The upper part of the stratigraphy (\textasciitilde1 m thick) displays rocks with different compositions suggesting a strong change in the depositional system. The presence of float rocks with similar compositions found along the rover traverse suggests that some of these outcrops extend further away in the nearby hummocky plains.

@article{mangold_chemical_2015,
	title = {Chemical variations in {Yellowknife} {Bay} formation sedimentary rocks analyzed by {ChemCam} on board the {Curiosity} rover on {Mars}},
	volume = {120},
	issn = {2169-9100},
	url = {http://onlinelibrary.wiley.com/doi/10.1002/2014JE004681/abstract},
	doi = {10.1002/2014JE004681},
	abstract = {The Yellowknife Bay formation represents a {\textasciitilde}5 m thick stratigraphic section of lithified fluvial and lacustrine sediments analyzed by the Curiosity rover in Gale crater, Mars. Previous works have mainly focused on the mudstones that were drilled by the rover at two locations. The present study focuses on the sedimentary rocks stratigraphically above the mudstones by studying their chemical variations in parallel with rock textures. Results show that differences in composition correlate with textures and both manifest subtle but significant variations through the stratigraphic column. Though the chemistry of the sediments does not vary much in the lower part of the stratigraphy, the variations in alkali elements indicate variations in the source material and/or physical sorting, as shown by the identification of alkali feldspars. The sandstones contain similar relative proportions of hydrogen to the mudstones below, suggesting the presence of hydrous minerals that may have contributed to their cementation. Slight variations in magnesium correlate with changes in textures suggesting that diagenesis through cementation and dissolution modified the initial rock composition and texture simultaneously. The upper part of the stratigraphy ({\textasciitilde}1 m thick) displays rocks with different compositions suggesting a strong change in the depositional system. The presence of float rocks with similar compositions found along the rover traverse suggests that some of these outcrops extend further away in the nearby hummocky plains.},
	language = {en},
	number = {3},
	urldate = {2017-03-30TZ},
	journal = {Journal of Geophysical Research: Planets},
	author = {Mangold, N. and Forni, O. and Dromart, G. and Stack, K. and Wiens, R. C. and Gasnault, O. and Sumner, D. Y. and Nachon, M. and Meslin, P.-Y. and Anderson, R. B. and Barraclough, B. and Bell, J. F. and Berger, G. and Blaney, D. L. and Bridges, J. C. and Calef, F. and Clark, B. and Clegg, S. M. and Cousin, A. and Edgar, L. and Edgett, K. and Ehlmann, B. and Fabre, C. and Fisk, M. and Grotzinger, J. and Gupta, S. and Herkenhoff, K. E. and Hurowitz, J. and Johnson, J. R. and Kah, L. C. and Lanza, N. and Lasue, J. and Le Mouélic, S. and Léveillé, R. and Lewin, E. and Malin, M. and McLennan, S. and Maurice, S. and Melikechi, N. and Mezzacappa, A. and Milliken, R. and Newsom, H. and Ollila, A. and Rowland, S. K. and Sautter, V. and Schmidt, M. and Schröder, S. and d'Uston, C. and Vaniman, D. and Williams, R.},
	month = mar,
	year = {2015},
	keywords = {5410 Composition, 5415 Erosion and weathering, 5419 Hydrology and fluvial processes, 6225 Mars, 8045 Role of fluids, ChemCam, Gale crater, LIBS, Mars, sediments},
	pages = {2014JE004681}
}

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