^1,2T. J. Barrett,^1,3A. J. King,¹G. Degli-Alessandrini,⁴S. J. Hammond,³E. Humphreys-Williams,³B. Schmidt,¹R. C. Greenwood,¹F. A. J. Abernethy,^1,3M. Anand,⁵E. Rudnickaitė
Meteoritics & Planetary Science (in Press) Open Access Link to Article [https://doi.org/10.1111/maps.14229]
¹School of Physical Sciences, The Open University, Milton Keynes, UK
²Center for Lunar Science and Exploration, Lunar and Planetary Institute, Houston, Texas, USA
³Planetary Materials Group, Natural History Museum, London, UK
⁴School of Environment, Earth, and Ecosystem Sciences, The Open University, Milton Keynes, UK
⁵Department of Geology and Mineralogy, Museum of Geology of Vilnius University, Vilnius, Lithuania
Published by arrangement with John Wiley & Sons

The Padvarninkai meteorite is a relatively understudied eucrite, initially misclassified as a shergottite given its strong shock characteristics. In this study, a comprehensive examination of the petrology; mineral composition; major, minor, and trace element abundances; and isotopic composition (C, O) is presented. Padvarninkai is a monomict eucrite consisting of a fine to coarse-grained lithology and impact melt veins. Pyroxene grains are typically severely fractured and mosaicked whilst plagioclase is either partially or totally converted to maskelynite. Based on shock features observed in pyroxene, plagioclase, and apatite, Padvarninkai can be given a shock classification of M-S4/5. Despite the high shock experienced by this sample, some of the original igneous textures remain. Compositionally, Padvarninkai is a main group eucrite with a flat REE pattern (~10–12 × CI) and elevated Ni abundances. Whilst both new and literature oxygen isotopes are similar to other eucrites, however, Padvarninkai displays an anomalously high δ13C value. To reconcile the high Ni and δ13C value, impact contamination modeling was conducted. These models could not reconcile both the high Ni and δ13C value with the eucritic δ18O values, arguing against impact as a source for these anomalies.