Journal Article

Deposition, exhumation, and paleoclimate of an ancient lake deposit, Gale crater, Mars

McLennan, S. M., Gupta, S., Sumner, D. Y., Dietrich, W. E., Schieber, J., Calef, F., Rice, M., Kocurek, G., Blaney, D., Conrad, P., Ming, D., Yingst, R. A., Wiens, R. C., Wilson, S. A., Williams, R. M. E., Palucis, M., Hurowitz, J. A., Ewing, R. C., Newsom, H., McBride, M. J., Gellert, R., Rubin, D. M., Arvidson, R. E., Edgar, L., Edgett, K. S., Stack, K. M., Mischna, M., Vaniman, D., Grant, J. A., Parker, T. J., Griffes, J., Dromart, G., Grotzinger, J. P., Lewis, K. W., Lamb, M. P., Fischer, W. F., Blake, D., Vasavada, A. R., Crisp, J., Siebach, K., Minitti, M. E., Mahaffy, P., Oehler, D., Malin, M. C., Kah, L. C., Mangold, N., Milliken, R.

2015

Overview

Since 2012, the Curiosity rover has been diligently studying rocky outcrops on Mars, looking for clues about past water, climate, and habitability. Grotzinger et al. describe the analysis of a huge section of sedimentary rocks near Gale crater, where Mount Sharp now stands (see the Perspective by Chan). The features within these sediments are reminiscent of delta, stream, and lake deposits on Earth. Although individual lakes were probably transient, it is likely that there was enough water to fill in low-lying depressions such as impact craters for up to 10,000 years. Wind-driven erosion removed many of these deposits, creating Mount Sharp. Science , this issue p. 10.1126/science.aac7575 , see also p. 167 Mount Sharp now stands where there was once a large intercrater lake system. [Also see Perspective by Chan ] The landforms of northern Gale crater on Mars expose thick sequences of sedimentary rocks. Based on images obtained by the Curiosity rover, we interpret these outcrops as evidence for past fluvial, deltaic, and lacustrine environments. Degradation of the crater wall and rim probably supplied these sediments, which advanced inward from the wall, infilling both the crater and an internal lake basin to a thickness of at least 75 meters. This intracrater lake system probably existed intermittently for thousands to millions of years, implying a relatively wet climate that supplied moisture to the crater rim and transported sediment via streams into the lake basin. The deposits in Gale crater were then exhumed, probably by wind-driven erosion, creating Aeolis Mons (Mount Sharp).

• Publisher: American Association for the Advancement of Science,The American Association for the Advancement of Science,American Association for the Advancement of Science (AAAS)
• Subject: Climate / Craters / Curiosity (Mars rover) / Deltas / Deposits / Diagenesis / Evaporation / Exhumation / Gravel / Lake basins / Lakes / Landforms / Mars / Mars craters / Mars surface / Mesas / Paleoclimate / Paleoclimate science / Paleontology / Personality Traits / RESEARCH ARTICLE SUMMARY / Sand / Science Laboratories / Sciences of the Universe / Sedimentary geology / Sedimentary rocks / Sediments / Stratigraphy / Water / Water availability / Water table / Wet climates / Wind