Properties of the Nili Fossae Olivine-clay-carbonate lithology: orbital and in situ at Séítah
astro-ph.EP
/ Authors
Adrian J. Brown, Linda Kah, Lucia Mandon, Roger Wiens, Patrick Pinet, Elise Clavé, Stéphane Le Mouélic, Arya Udry, Patrick J. Gasda, Clément Royer
and 24 more authors
Keyron Hickman-Lewis11, Agnes Cousin, Justin I. Simon, Jade Comellas14, Edward Cloutis, Thierry Fouchet, Alberto G. Fairén, Stephanie Connell, David Flannery, Briony Horgan, Lisa Mayhew, Allan Treiman, Jorge I. Núñez, Brittan Wogsland, Karim Benzerara, Hans E. F. Amundsen, Cathy Quantin-Nataf, Kevin P. Hand, Vinciane Debaille, Ari Essunfeld, Pierre Beck, Nicholas J. Tosca
/ Abstract
We examine the observed properties of the Nili Fossae olivine-clay-carbonate lithology from orbital data and in situ by the Mars 2020 rover at the Séítah unit in Jezero crater, including: 1) composition (Liu, 2022) 2) grain size (Tice, 2022) 3) inferred viscosity (calculated based on geochemistry collected by SuperCam (Wiens, 2022)). Based on the low viscosity and distribution of the unit we postulate a flood lava origin for the olivine-clay-carbonate at Séítah. We include a new CRISM map of the clay 2.38 μm band and use in situ data to show that the clay in the olivine cumulate in the Séítah formation is consistent with talc or serpentine from Mars 2020 SuperCam LIBS and VISIR and MastCam-Z observations. We discuss two intertwining aspects of the history of the lithology: 1) the emplacement and properties of the cumulate layer within a lava lake, based on terrestrial analogs in the Pilbara, Western Australia, and using previously published models of flood lavas and lava lakes, and 2) the limited extent of post emplacement alteration, including clay and carbonate alteration (Clave, 2022; Mandon, 2022).