GSA Connects 2021 in Portland, Oregon

Paper No. 14-13
Presentation Time: 11:15 AM


HORGAN, Briony1, RICE, Melissa2, KAH, Linda3, GUPTA, Sanjeev4, MANGOLD, Nicolas5, BELL III, James6, KINCH, Kjartan7, JOHNSON, Jeffrey8, MILLION, Chase9, NÚÑEZ, Jorge8, PAAR, Gerhard10, ST. CLAIR, Michael9, TATE, Christian11, VAUGHAN, Alicia12, RAVANIS, Eleni13, FAGENTS, Sarah A.13 and BROWN, Adrian14, (1)550 Stadium Mall Dr.Earth, Atmospheric, and Planetary Sci, 516 High St, Bellingham, WA 98225, (2)Geology, Western Washington University, 516 High St, Bellingham, WA 98225, (3)Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, (4)Imperial College London, London, SW7 2AZ, United Kingdom, (5)Laboratoire De Planétologie Et Géodynamique, U. Nantes, Nantes, 44322, France, (6)School of Earth & Space Exploration, Arizona State University, Tempe, AZ 85287, (7)Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark, (8)Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, MP3-E169, Laurel, MD 20723, (9)Million Concepts, Louisville, KY 40203, (10)Joanneum Research, Steyrergasse 17, Graz, 8010, Austria, (11)Cornell University, Ithaca, NY 14853, (12)USGS, Astrogeology Science Center, Flagstaff, AZ 86001, (13)Hawai'i Institute of Geophysics & Planetology, University of Hawai'i, Honolulu, HI 96822, (14)Plancius Research, 1106 BELLEVISTA CT, SEVERNA PARK, MD 21146

Jezero crater exhibits significant spectral diversity in orbital short wave-infrared (SWIR; 1000-2600 nm) images, including a variety of primary minerals, carbonates, silica, and phyllosilicates. These minerals are detected in the crater rim, delta, marginal deposits, and crater floor, and have been variously interpreted as indicating fluvial or aeolian sediments, tephra, lake precipitates, and lavas. In this study, we link interpretations of depositional processes from Perseverance rover data to regional mineral detections, which is critical for placing returned samples in context, establishing sediment provenance, and informing rover strategic path planning.

The Mastcam-Z cameras on Perseverance have acquired spectacular images of the landing site in Jezero, in standard color and through 14 multispectral filters in the visible/near-infrared (VNIR; 440-1100 nm), both in 3D from stereo images. Here we compare spectral diversity observed by Mastcam-Z in the vicinity of the rover and in long-distance observations to orbital spectra from the CRISM imaging spectrometer as well as HiRISE images and DTMs.

We find that the orbital spectra can be tied to specific rock and regolith units in Jezero, but that additional spectral diversity is present at outcrop scales. Deltaic deposits exhibit spectral diversity that corresponds to sedimentological facies, suggesting variations in sediment sources, grain size sorting, or post-depositional alteration. Crater floor units encountered by Perseverance so far are consistent with clastic rocks, and based on spectral similarities to the Jezero rim and delta, we hypothesize that some crater floor units are sourced from fluvial or aeolian erosion of these areas, potentially representing the last phase of sedimentation in Jezero. However, we are also evaluating other origin scenarios, for example, volcanic tephra deposited directly into the crater or reworked by aeolian or fluviolacstrine processes, which would be a valuable sampling target for geochronology.