PMID- 33282614
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20240330
IS  - 2169-9097 (Print)
IS  - 2169-9100 (Electronic)
IS  - 2169-9097 (Linking)
VI  - 125
IP  - 11
DP  - 2020 Nov
TI  - Diagenesis of Vera Rubin Ridge, Gale Crater, Mars, From Mastcam Multispectral 
      Images.
PG  - e2019JE006322
LID - 10.1029/2019JE006322 [doi]
LID - e2019JE006322
AB  - Images from the Mars Science Laboratory (MSL) mission of lacustrine sedimentary 
      rocks of Vera Rubin ridge on "Mt. Sharp" in Gale crater, Mars, have shown stark 
      color variations from red to purple to gray. These color differences crosscut 
      stratigraphy and are likely due to diagenetic alteration of the sediments after 
      deposition. However, the chemistry and timing of these fluid interactions is 
      unclear. Determining how diagenetic processes may have modified chemical and 
      mineralogical signatures of ancient Martian environments is critical for 
      understanding the past habitability of Mars and achieving the goals of the MSL 
      mission. Here we use visible/near-infrared spectra from Mastcam and ChemCam to 
      determine the mineralogical origins of color variations in the ridge. Color 
      variations are consistent with changes in spectral properties related to the 
      crystallinity, grain size, and texture of hematite. Coarse-grained gray hematite 
      spectrally dominates in the gray patches and is present in the purple areas, 
      while nanophase and fine-grained red crystalline hematite are present and 
      spectrally dominate in the red and purple areas. We hypothesize that these 
      differences were caused by grain-size coarsening of hematite by diagenetic 
      fluids, as observed in terrestrial analogs. In this model, early primary 
      reddening by oxidizing fluids near the surface was followed during or after 
      burial by bleaching to form the gray patches, possibly with limited secondary 
      reddening after exhumation. Diagenetic alteration may have diminished the 
      preservation of biosignatures and changed the composition of the sediments, 
      making it more difficult to interpret how conditions evolved in the paleolake 
      over time.
CI  - (c)2020. The Authors.
FAU - Horgan, Briony H N
AU  - Horgan BHN
AUID- ORCID: 0000-0001-6314-9724
AD  - Department of Earth, Atmospheric, and Planetary Sciences Purdue University West 
      Lafayette IN USA.
FAU - Johnson, Jeffrey R
AU  - Johnson JR
AUID- ORCID: 0000-0002-5586-4901
AD  - Johns Hopkins University Applied Physics Laboratory Laurel MD USA.
FAU - Fraeman, Abigail A
AU  - Fraeman AA
AUID- ORCID: 0000-0003-4017-5158
AD  - Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA.
FAU - Rice, Melissa S
AU  - Rice MS
AUID- ORCID: 0000-0002-8370-4139
AD  - Geology Department, Physics and Astronomy Department Western Washington 
      University Bellingham WA USA.
FAU - Seeger, Christina
AU  - Seeger C
AUID- ORCID: 0000-0003-4993-9724
AD  - Geology Department, Physics and Astronomy Department Western Washington 
      University Bellingham WA USA.
AD  - Division of Geological and Planetary Sciences California Institute of Technology 
      Pasadena CA USA.
FAU - Bell, James F 3rd
AU  - Bell JF 3rd
AUID- ORCID: 0000-0002-2006-4074
AD  - School of Earth and Space Exploration Arizona State University Tempe AZ USA.
FAU - Bennett, Kristen A
AU  - Bennett KA
AUID- ORCID: 0000-0001-8105-7129
AD  - U.S. Geological Survey Astrogeology Science Center Flagstaff AZ.
FAU - Cloutis, Edward A
AU  - Cloutis EA
AUID- ORCID: 0000-0001-7301-0929
AD  - Department of Geography University of Winnipeg Winnipeg Manitoba Canada.
FAU - Edgar, Lauren A
AU  - Edgar LA
AUID- ORCID: 0000-0001-7512-7813
AD  - U.S. Geological Survey Astrogeology Science Center Flagstaff AZ.
FAU - Frydenvang, Jens
AU  - Frydenvang J
AUID- ORCID: 0000-0001-9294-1227
AD  - Globe Institute University of Copenhagen Copenhagen Denmark.
FAU - Grotzinger, John P
AU  - Grotzinger JP
AD  - Division of Geological and Planetary Sciences California Institute of Technology 
      Pasadena CA USA.
FAU - L'Haridon, Jonas
AU  - L'Haridon J
AUID- ORCID: 0000-0002-9323-1603
AD  - Laboratoire de Planetologie et Geodynamique CNRS, Univ Nantes, Univ Angers Nantes 
      France.
FAU - Jacob, Samantha R
AU  - Jacob SR
AUID- ORCID: 0000-0001-9950-1486
AD  - School of Earth and Space Exploration Arizona State University Tempe AZ USA.
FAU - Mangold, Nicolas
AU  - Mangold N
AUID- ORCID: 0000-0002-0022-0631
AD  - Laboratoire de Planetologie et Geodynamique CNRS, Univ Nantes, Univ Angers Nantes 
      France.
FAU - Rampe, Elizabeth B
AU  - Rampe EB
AUID- ORCID: 0000-0002-6999-0028
AD  - NASA Johnson Space Center Houston TX USA.
FAU - Rivera-Hernandez, Frances
AU  - Rivera-Hernandez F
AUID- ORCID: 0000-0003-1401-2259
AD  - Department of Earth Sciences Dartmouth College Hanover NH USA.
FAU - Sun, Vivian Z
AU  - Sun VZ
AUID- ORCID: 0000-0003-1480-7369
AD  - Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA.
FAU - Thompson, Lucy M
AU  - Thompson LM
AUID- ORCID: 0000-0002-5444-952X
AD  - Planetary and Space Science Centre University of New Brunswick Fredericton New 
      Brunswick Canada.
FAU - Wellington, Danika
AU  - Wellington D
AD  - School of Earth and Space Exploration Arizona State University Tempe AZ USA.
LA  - eng
PT  - Journal Article
DEP - 20201031
PL  - United States
TA  - J Geophys Res Planets
JT  - Journal of geophysical research. Planets
JID - 101661797
PMC - PMC7685111
OTO - NOTNLM
OT  - Mars
OT  - diagenesis
OT  - mineralogy
OT  - spectroscopy
EDAT- 2020/12/08 06:00
MHDA- 2020/12/08 06:01
PMCR- 2020/11/24
CRDT- 2020/12/07 05:34
PHST- 2019/12/10 00:00 [received]
PHST- 2020/09/03 00:00 [revised]
PHST- 2020/09/19 00:00 [accepted]
PHST- 2020/12/07 05:34 [entrez]
PHST- 2020/12/08 06:00 [pubmed]
PHST- 2020/12/08 06:01 [medline]
PHST- 2020/11/24 00:00 [pmc-release]
AID - JGRE21485 [pii]
AID - 10.1029/2019JE006322 [doi]
PST - ppublish
SO  - J Geophys Res Planets. 2020 Nov;125(11):e2019JE006322. doi: 10.1029/2019JE006322. 
      Epub 2020 Oct 31.