Composition, Stratigraphy, and Geological History of the Noachian Basement Surrounding the Isidis Impact Basin

The western part of the Isidis basin structure hosts a well‐characterized Early Noachian to Amazonian stratigraphy. The Noachian Basement comprises its oldest exposed rocks (Early to Mid‐Noachian) and was previously considered a single low‐Ca pyroxenes (LCP)‐ and Fe/Mg‐smectite‐bearing unit. Here, we divide the Noachian Basement Group into five distinct geological units (Stratified Basement Unit, Blue Fractured Unit, Mixed Lithology Plains Unit, LCP‐bearing Plateaus Unit, and Fe/Mg‐smectite‐bearing Mounds Unit), two geomorphological features (megabreccia and ridges), and a mineral deposit (kaolinite‐bearing bright materials), based on geomorphology, spectral characteristics, and stratigraphic relationships. Megabreccia contain four different pre‐Isidis lithologies, possibly including deeper crust or mantle materials, formed through mass wasting associated with transient crater collapse during Isidis basin formation. The Fe/Mg‐smectite‐bearing Stratified Basement Unit and LCP‐bearing Blue Fractured Unit likewise represent pre‐Isidis units within the Noachian Basement Group. Multiple Fe/Mg‐smectite‐bearing geological units with different stratigraphic positions and younger kaolinite‐bearing bright materials indicate several aqueous alteration episodes of different ages and styles. Units with slight changes in pyroxene spectral properties suggest a transition from low‐Ca pyroxene‐containing materials to those with higher proportions of pyroxenes higher in Ca and/or glass that could be related to different impact and/or igneous processes, or provenance. This long history of Noachian and potentially Pre‐Noachian geological processes, including impact basin formation, aqueous alteration, and multiple igneous and sedimentary petrogeneses, records changing ancient Mars environmental conditions. All units defined by this study are available 20 km outside of Jezero crater for in situ analysis and sampling during a potential extended mission scenario for the Mars 2020 rover

Aqueous alteration processes in Jezero crater, Mars—implications for organic geochemistry

The Perseverance rover landed in Jezero crater, Mars, in February 2021. We used the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument to perform deep-ultraviolet Raman and fluorescence spectroscopy of three rocks within the crater. We identify evidence for two distinct ancient aqueous environments at different times. Reactions with liquid water formed carbonates in an olivine-rich igneous rock. A sulfate-perchlorate mixture is present in the rocks, which probably formed by later modifications of the rocks by brine. Fluorescence signatures consistent with aromatic organic compounds occur throughout these rocks and are preserved in minerals related to both aqueous environments

Mars D/H model and KINETICS data files

Please find 2 zip folders: (1) Mars_DH_Model contains a scientific python script used to explore Martian water loss and history in Scheller et al. (2021); Science. (2) Mars_KINETICS_Model contains all files that include input, output, equations, and a data exploration script used for modelling past hydrogen escape rates in Scheller et al. (2021); Science through an adaptation of KINETICS (original software from Allen et al., 1981 and Nair et al., 1994). Read the readme and comments to learn how to use any of the scripts and to understand data formats.Related Publication: Long-term Drying of Mars Caused by Sequestration of Ocean-scale Volumes of Water in the Crust Eva L. Scheller Caltech Science en

Formation of Magnesium Carbonates on Earth and Implications for Mars - Fig. 6 dataset

This is the data set used to create Fig. 6 in the paper "Formation of Magnesium Carbonates on Earth and Implications for Mars" by Scheller et al., published in JGR: Planets. The data set was created through a literature review. The associated references are listed for all data entries

Supplementary data tables for Composition, Stratigraphy, and Geological History of the Noachian Basement Surrounding the Isidis Impact Basin

Three supplementary data tables: Supplement 1 contains the texture and HiRISE color properties evaluated for all mapped megabreccia outcrops. Megabreccia outcrop positions are given as X,Y,elevation-locations in the global MOLA mosaic with projection of SimpleCylindrical_Mars. Supplement 2 contains all measured megabreccia block sizes and their locations in the same format as supplement 1. Supplement 3 contains all orientation measurements (strike, dip, and rake errors) from layers and contact segments of Stratified Basement within 2 different HiRISE DEMs

THE PETROGENETIC HISTORY OF THE JEZERO CRATER DELTA FRONT FROM MICROSCALE OBSERVATIONS BY THE MARS 2020 PIXL INSTRUMENT

International audienceOn ~sol 370 of the Perseverance rover mission, the Mars 2020 Science Team completed its investigation of igneous units of the Jezero crater floor [1] and directed Perseverance to drive towards the topographic scarp that marks the interface between the crater floor and Jezero’s western delta. The “Delta Front Campaign” consisted of close-up investigation and sampling of lithologies located there.Here, we report on the major findings relevant to the provenance and diagenetic history of these lithologies deduced from measurements made by the Planetary Instrument for X-ray Lithochemistry (PIXL), a micro-focus X-ray fluorescence (XRF) microscope [2]. Data were collected from two sections at Cape Nukshak and Hawksbill Gap; outcrop and member names are from [3]. Lithologies are described here in order from base to top of each section

THE PETROGENETIC HISTORY OF THE JEZERO CRATER DELTA FRONT FROM MICROSCALE OBSERVATIONS BY THE MARS 2020 PIXL INSTRUMENT

International audienceOn ~sol 370 of the Perseverance rover mission, the Mars 2020 Science Team completed its investigation of igneous units of the Jezero crater floor [1] and directed Perseverance to drive towards the topographic scarp that marks the interface between the crater floor and Jezero’s western delta. The “Delta Front Campaign” consisted of close-up investigation and sampling of lithologies located there.Here, we report on the major findings relevant to the provenance and diagenetic history of these lithologies deduced from measurements made by the Planetary Instrument for X-ray Lithochemistry (PIXL), a micro-focus X-ray fluorescence (XRF) microscope [2]. Data were collected from two sections at Cape Nukshak and Hawksbill Gap; outcrop and member names are from [3]. Lithologies are described here in order from base to top of each section