The history of the Tissint meteorite, from its crystallization on Mars to its exposure in space: New geochemical, isotopic, and cosmogenic nuclide data

1,2Toni Schulz,3Pavel P. Povinec,4Ludovic Ferrière,5,6A. J. Timothy Jull,3Andrej Kováčik,3Ivan Sýkora,2Jonas Tusch,2Carsten Münker,4Dan Topa,1,4Christian Koeberl
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.13435]
1Department of Lithospheric Research, University Vienna, Althanstrasse 14, 1090 Vienna, Austria
2Institut für Geologie und Mineralogie, Universität zu Köln, Zülpicher Strasse 49b, 50674 Köln, Germany
3Faculty of Mathematics, Physics and Informatics, Department of Nuclear Physics and Biophysics, Comenius University, SK‐84248 Bratislava, Slovakia
4Natural History Museum, Burgring 7, 1010 Vienna, Austria
5Department of Geosciences, University of Arizona, Tucson, Arizona, 85721 USA
6Hungarian Academy of Sciences, Institute for Nuclear Research, ICER, 4026 Debrecen, Hungary
7MicroStep‐MIS, 84104 Bratislava, Slovakia
Published by arrangement with John Wiley & Sons

The Tissint meteorite fell on July 18, 2011 in Morocco and was quickly recovered, allowing the investigation of a new unaltered sample from Mars. We report new high‐field strength and highly siderophile element (HSE) data, Sr‐Nd‐Hf‐W‐Os isotope analyses, and data for cosmogenic nuclides in order to examine the history of the Tissint meteorite, from its source composition and crystallization to its irradiation history. We present high‐field strength element compositions that are typical for depleted Martian basalts (0.174 ppm Nb, 17.4 ppm Zr, 0.7352 ppm Hf, and 0.0444 ppm W), and, together with an extended literature data set for shergottites, help to reevaluate Mars’ tectonic evolution in comparison to that of the early Earth. HSE contents (0.07 ppb Re, 0.92 ppb Os, 2.55 ppb Ir, and 7.87 ppb Pt) vary significantly in comparison to literature data, reflecting significant sample inhomogeneity. Isotope data for Os and W (187Os/188Os = 0.1289 ± 15 and an ε182W = +1.41 ± 0.46) are both indistinguishable from literature data. An internal Lu‐Hf isochron for Tissint defines a crystallization age of 665 ± 74 Ma. Considering only Sm‐Nd and Lu‐Hf chronometry, we obtain, using our and literature values, a best estimate for the age of Tissint of 582 ± 18 Ma (MSWD = 3.2). Cosmogenic radionuclides analyzed in the Tissint meteorite are typical for a recent fall. Tissint’s pre‐atmospheric radius was estimated to be 22 ± 2 cm, resulting in an estimated total mass of 130 ± 40 kg. Our cosmic‐ray exposure age of 0.9 ± 0.2 Ma is consistent with earlier estimations and exposure ages for other shergottites in general.

Discuss

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s