Sedimentary and stratigraphic observations at the Jezero western delta front using Perseverance cameras: initial constraints on palaeoenvironments

Sanjeev Gupta (1) , Jim F. Bell (2) , Oak Kanine (3) , Christian Tate , Gwénaël Caravaca (4) , Jorge Núñez (5) , Nicolas Mangold (6) , Gilles Dromart (7) , Stéphane Le Mouélic (6) , Andrew Annex , Gerhard Paar (8) , Sanna Holm-Alwmark , Melissa S. Rice , Jim Rice (2) , Briony Horgan (9) , John Grotzinger (3) , Justin Maki (10) , Keyron Hickman Lewis (11) , Lindah C. Kah (12) , David L. Shuster (13) , Justin I. Simon (14) , Olivier Gasnault (4) , Roger C Wiens (15) , Sylvestre Maurice (4) , Kathryn Stack (10) , Kenneth A. Farley (16)

1 Department of Earth Science and Engineering [Imperial College London]
2 ASU - Arizona State University [Tempe]
3 Division of Geological and Planetary Sciences [Pasadena]
4 IRAP - Institut de recherche en astrophysique et planétologie
5 APL - Johns Hopkins University Applied Physics Laboratory [Laurel, MD]
6 LPG - Laboratoire de Planétologie et Géosciences [UMR_C 6112]
7 LGL-TPE - Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement
8 Joanneum Research Forschungsgesellschaft mbH
9 Department of Earth, Atmospheric, and Planetary Sciences, Purdue University
10 JPL - Jet Propulsion Laboratory
11 CBM - Centre de biophysique moléculaire
12 The University of Tennessee [Knoxville]
13 BGC - Berkeley Geochronology Center
14 JSC - NASA Johnson Space Center
15 EAPS - Department of Earth, Atmospheric, and Planetary Sciences [West Lafayette]
16 CALTECH - California Institute of Technology

NASA’s Mars 2020 Perseverance rover mission is seeking signs of ancient life in Jezero crater and is collecting a cache of Martian rock and soil samples for planned return to Earth by a future mission. A key exploration target for the mission is a prominent sedimentary fan deposit at the western margin of Jezero crater that has been interpretated to be a river delta that built into an ancient lake basin during the Late Noachian-Early Hesperian epochs on Mars (~3.6-3.8 Ga) [1, 2]. Long distance observations of a remnant butte (informally named Kodiak) related to the western fan demonstrated that it comprised two distinct Gilbert-type delta units [2, 3]. In her approach to the western fan, Perseverance drove alongside the east-facing scarp of the western fan and arrived at a key location called Three Forks - a setting off point for delta exploration - in April 2022. Images from the Mastcam-Z and SuperCam Remote Micro-Imager instruments provide new views of the stratigraphy exposed in the erosional front of the western Jezero delta; in particular, showing sections of the delta previously not visible from long distance observations and at much higher resolution. These observations provide the first direct evidence of delta geometries in the main western fan deposit. Here, we report its stratigraphy and sedimentology, which provide new constraints on the nature of the fan deposits, and therefore paleoenvironmental implications.

Domaines: Planète et Univers [physics]; Stratigraphie; Sciences de la Terre; Planétologie

Sanjeev Gupta, Jim F. Bell, Oak Kanine, Christian Tate, Gwénaël Caravaca, et al.. Sedimentary and stratigraphic observations at the Jezero western delta front using Perseverance cameras: initial constraints on palaeoenvironments. Europlanet Science Congress 2022, Europlanet, Sep 2022, Granada, Spain. pp.EPSC2022-1098, ⟨10.5194/epsc2022-1098⟩. ⟨hal-03842508⟩