High flow capacity and low viscosity of the Séítah formation, at Jezero Crater, Mars
Abstract
Abstract The unexpected discovery of olivine cumulate at the Séítah Formation within Jezero Crater was one of the most compelling findings of the Mars2020 Perseverance rover mission thus far. Compared to Earth, Mars is a basaltic world and differences in gravity, atmosphere and volatile content imply commensurate changes in lava flow dynamics that need to be better understood. We use rover geochemistry data to calculate the viscosity and relative flow distance of the Séítah unit and its parental lava. We suggest the olivine cumulate discovered by the rover was related to a ponded lava flow, based on the low viscosity and distribution of the unit. We estimate an approximate relative depth for the cumulate layer of the lava pond using a convective lava magma model. We also compare the Noachian Jezero olivine rich viscosities to Hesperian basalts analysed by Spirit, and find the Noachian samples to have a greater propensity to flow than their younger cousins. Future observations of the olivine rich unit and laboratory studies of the samples collected by Mars2020 will provide a deep window into the flow dynamics and evolution of Martian lava flows.
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Authors: Adrian Jon Brown, Linda C. Kah, R. C. Wiens, P. Pinet, P. J. Gasda, Clément Royer, C. Royer, A. Cousin, Justin I. Simon, Jade Comellas, E. A. Cloutis, Thierry Fouchet, Alberto G. Fairén, Stephanie Connell, David Timothy Flannery, Jorge I. Núñez, Brittan Wogsland, Hans E. F. Amundsen, Kevin Hand, Vinciane Debaille, Ari Essenfeld, Pierre Beck, Nicholas J. Tosca, Juan Manuel Madariaga, Mitchell D. Schulte, C. D. K. Herd, M. E. Schmidt, O. Forni
Institutions: University of Alberta, Cornell University, University of the Basque Country, Université Grenoble Alpes, Université Paris Cité, Sorbonne Université, University of Cambridge, Centre National de la Recherche Scientifique, Queensland University of Technology, University of Tennessee at Knoxville, The University of Winnipeg, Purdue University West Lafayette, University of London, Université Paris Sciences et Lettres, Brock University, Los Alamos National Laboratory, Centro de Astrobiología, Université Libre de Bruxelles, Observatoire de Paris, Johns Hopkins University Applied Physics Laboratory, Jet Propulsion Laboratory, National Aeronautics and Space Administration, Johnson Space Center, Birkbeck, University of London, Université Paris Dauphine-PSL, Institut de Recherche en Astrophysique et Planétologie, Institut de Planétologie et d'Astrophysique de Grenoble, Observatoire Midi-Pyrénées, Université de Toulouse, Laboratoire d’études spatiales et d’instrumentation en astrophysique