Two billion years of magmatism recorded from a single Mars meteorite ejection site
Thomas J. Lapen 1,*, Minako Righter 1, Rasmus Andreasen 1,2, Anthony J. Irving 3, Aaron M. Satkoski 4,5, Brian L. Beard 4,5, Kunihiko Nishiizumi 6, A. J. Timothy Jull 7 and Marc W. Caffee 8,9
- Author Affiliations
1Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204–5007, USA.
2Department of Geoscience, Aarhus University, Aarhus, Denmark.
3Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195–1310, USA.
4Department of Geoscience, University of Wisconsin–Madison, Madison, WI 53706–1692, USA.
5NASA Astrobiology Institute, University of Wisconsin–Madison, Madison, WI 53706, USA.
6Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA, USA.
7Department of Geosciences, University of Arizona, Tucson, AZ 85721, USA.
8Department of Physics, Purdue University, West Lafayette, IN 47907–2036, USA.
9Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN 47907–2051, USA.
↵*Corresponding author. Email: tjlapen@uh.edu
Science Advances 01 Feb 2017: Vol. 3, no. 2, e1600922
Source/Fonte: University of Houston, TX, USA
Abstract
The timing and nature of igneous activity recorded at a single Mars ejection site can be determined from the isotope analyses of Martian meteorites. Northwest Africa (NWA) 7635 has an Sm-Nd crystallization age of 2.403 ± 0.140 billion years, and isotope data indicate that it is derived from an incompatible trace element–depleted mantle source similar to that which produced a geochemically distinct group of 327- to 574-million-year-old “depleted” shergottites. Cosmogenic nuclide data demonstrate that NWA 7635 was ejected from Mars 1.1 million years ago (Ma), as were at least 10 other depleted shergottites. The shared ejection age is consistent with a common ejection site for these meteorites. The spatial association of 327- to 2403-Ma depleted shergottites indicates >2 billion years of magmatism from a long-lived and geochemically distinct volcanic center near the ejection site.
Keywords Mars Geochemistry Martian Meteorite Early Amazonian Magmatism Martian Mantle
Copyright © 2017, The Authors
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