Perseverance rover reveals ancient delta-lake system and flood deposits at Jezero crater, Mars

N. Mangold (1) , S Gupta , O Gasnault , G Dromart (2) , J D Tarnas , S F Sholes , B Horgan , C Quantin- Nataf (2) , A J Brown , S. Le Mouélic (1) , R A Yingst , J F Bell , O Beyssac (3) , T Bosak , F Calef , B L Ehlmann , K A Farley , J P Grotzinger , K Hickman-Lewis , S Holm-Alwmark , L C Kah , J Martinez-Frias , S M Mclennan , S Maurice (4) , J I Nuñez , A M Ollila , P Pilleri (4) , J W Rice , M Rice , J I Simon , D L Shuster , K M Stack , V Z Sun , A H Treiman , B P Weiss , R C Wiens , A J Williams , N R Williams , K H Williford

1 LPG - Laboratoire de Planétologie et Géodynamique [UMR 6112]
2 LGL-TPE - Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement
3 IMPMC - Institut de minéralogie, de physique des matériaux et de cosmochimie
4 IRAP - Institut de recherche en astrophysique et planétologie

Observations from orbital spacecraft have shown that Jezero crater, Mars, contains a prominent fan-shaped body of sedimentary rock deposited at its western margin. The Perseverance rover landed in Jezero crater in February 2021. We analyze images taken by the rover early in the mission, finding that the fan has outcrop faces that were invisible from orbit, which record the hydrological evolution of Jezero crater. We interpret the presence of inclined strata in these outcrops as evidence for deltas that advanced into a lake. By contrast, the uppermost fan strata are composed of boulder conglomerates, which imply deposition by episodic high-energy floods. This sedimentary succession indicates a transition from a sustained hydrologic activity in a persistent lake environment to highly energetic, short-duration fluvial flows.

Mots clés: Mars; Jezero crater; Hydrology Geomorphology fluvial 1625; Sedimentology

Domaines: Planétologie et astrophysique de la terre [astro-ph.EP]; Planétologie

N. Mangold, S Gupta, O Gasnault, G Dromart, J D Tarnas, et al.. Perseverance rover reveals ancient delta-lake system and flood deposits at Jezero crater, Mars. Science, inPress, ⟨10.1126/science.abl4051⟩. ⟨hal-03375854⟩