Exploring rock-regolith interfaces in Jezero crater with Mars 2020 SHERLOC
Abstract
The Perseverance rover successfully landed in Jezero crater, Mars in February 2021 at the Octavia E. Butler landing site and began its mission to explore and sample an ancient crater lake basin. Principal goals of the Mars 2020 mission are to characterize the geology and seeking signs of ancient microbial life on Mars. The Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument is a deep UV Raman spectrometer that utilizes a 248.6 nm pulsed laser. Part of SHERLOC is a color camera known as the Wide Angle Topographic Sensor for Operations and eNgineering (WATSON). The SHERLOC suite provides coordinated spectroscopic and imaging capabilities at high spatial resolution (~100 m), to detect minerals and organic molecules in microtextural context via resonance Raman and native fluorescence spectroscopy. SHERLOC enables texture-specific molecular composition measurements of rock and regolith targets on Mars. Coordinated rock-regolith observations illuminate insights into weathering processes and primary properties of rocks in Jezero crater. We describe the potential of rock-regolith interfaces to preserve unique records of geological processes in Jezero crater that supplement observations of the general rock record on Mars. Linking observations of local rock texture with associated regolith reveals lithologic information based on the interrelationship between differential weathering behavior and mineralogy, grain size, and cement chemistry. Preliminary observations indicate that the polygonally fractured lithotype common near the landing site may weather by granular disintegration and/or surface creep, a relation that can be explored at the rock-regolith interface. SHERLOC specific observations of textural and elemental composition transitions presented here trace rock-regolith boundaries at multiple indurated surfaces adjacent to regolith. At these locales, grain-scale based examinations suggest chemical weathering could be related to a variably distributed coating or rind on rock targets that may be mafic in composition. Granule deposits overlying widely distributed fine-grained material are also observed. Mineral identifications of each phase are presented, with cross-scale comparisons to the remote findings gained by SuperCam.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.P22B..03C