Cargando…

Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile

The Mars rover Spirit encountered outcrops and regolith composed of opaline silica (amorphous SiO(2)·nH(2)O) in an ancient volcanic hydrothermal setting in Gusev crater. An origin via either fumarole-related acid-sulfate leaching or precipitation from hot spring fluids was suggested previously. Howe...

Descripción completa

Detalles Bibliográficos
Autores principales: Ruff, Steven W., Farmer, Jack D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5473637/
https://www.ncbi.nlm.nih.gov/pubmed/27853166
http://dx.doi.org/10.1038/ncomms13554
_version_ 1783244321408942080
author Ruff, Steven W.
Farmer, Jack D.
author_facet Ruff, Steven W.
Farmer, Jack D.
author_sort Ruff, Steven W.
collection PubMed
description The Mars rover Spirit encountered outcrops and regolith composed of opaline silica (amorphous SiO(2)·nH(2)O) in an ancient volcanic hydrothermal setting in Gusev crater. An origin via either fumarole-related acid-sulfate leaching or precipitation from hot spring fluids was suggested previously. However, the potential significance of the characteristic nodular and mm-scale digitate opaline silica structures was not recognized. Here we report remarkably similar features within active hot spring/geyser discharge channels at El Tatio in northern Chile, where halite-encrusted silica yields infrared spectra that are the best match yet to spectra from Spirit. Furthermore, we show that the nodular and digitate silica structures at El Tatio that most closely resemble those on Mars include complex sedimentary structures produced by a combination of biotic and abiotic processes. Although fully abiotic processes are not ruled out for the Martian silica structures, they satisfy an a priori definition of potential biosignatures.
format Online
Article
Text
id pubmed-5473637
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher Nature Publishing Group
record_format MEDLINE/PubMed
spelling pubmed-54736372017-06-28 Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile Ruff, Steven W. Farmer, Jack D. Nat Commun Article The Mars rover Spirit encountered outcrops and regolith composed of opaline silica (amorphous SiO(2)·nH(2)O) in an ancient volcanic hydrothermal setting in Gusev crater. An origin via either fumarole-related acid-sulfate leaching or precipitation from hot spring fluids was suggested previously. However, the potential significance of the characteristic nodular and mm-scale digitate opaline silica structures was not recognized. Here we report remarkably similar features within active hot spring/geyser discharge channels at El Tatio in northern Chile, where halite-encrusted silica yields infrared spectra that are the best match yet to spectra from Spirit. Furthermore, we show that the nodular and digitate silica structures at El Tatio that most closely resemble those on Mars include complex sedimentary structures produced by a combination of biotic and abiotic processes. Although fully abiotic processes are not ruled out for the Martian silica structures, they satisfy an a priori definition of potential biosignatures. Nature Publishing Group 2016-11-17 /pmc/articles/PMC5473637/ /pubmed/27853166 http://dx.doi.org/10.1038/ncomms13554 Text en Copyright © 2016, The Author(s) http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
spellingShingle Article
Ruff, Steven W.
Farmer, Jack D.
Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile
title Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile
title_full Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile
title_fullStr Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile
title_full_unstemmed Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile
title_short Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile
title_sort silica deposits on mars with features resembling hot spring biosignatures at el tatio in chile
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5473637/
https://www.ncbi.nlm.nih.gov/pubmed/27853166
http://dx.doi.org/10.1038/ncomms13554
work_keys_str_mv AT ruffstevenw silicadepositsonmarswithfeaturesresemblinghotspringbiosignaturesateltatioinchile
AT farmerjackd silicadepositsonmarswithfeaturesresemblinghotspringbiosignaturesateltatioinchile