Biomolecules from fossilized hot spring sinters

implications for the search for life on mars

Bronwyn L. Teece, Simon C. George, Tara Djokic, Kathleen A. Campbell, Steven W. Ruff, Martin J. Van Kranendonk

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Hot spring environments are commonly dominated by silica sinters that precipitate by the rapid cooling of silica-saturated fluids and the activity of microbial communities. However, the potential for preservation of organic traces of life in silica sinters back through time is not well understood. This is important for the exploration of early life on Earth and possibly Mars. Most previous studies have focused on physical preservation in samples <900 years old, with only a few focused on organic biomarkers. In this study, we investigate the organic geochemistry of hot spring samples from El Tatio, Chile and the Taupo Volcanic Zone, with ages varying from modern to ∼9.4 ka. Results show that all samples contain opaline silica and contain hydrocarbons that are indicative of a cyanobacterial origin. A ∼3 ka recrystallized, quartz-bearing sample also contains traces of cyanobacterial biomarkers. No aromatic compounds were detected in a ∼9.4 ka opal-A sample or in a modern sinter breccia sample. All other samples contain naphthalene, with one sample also containing other polyaromatic hydrocarbons. These aromatic hydrocarbons have a thermally mature distribution that is perhaps reflective of geothermal fluids migrating from deep, rather than surface, reservoirs. These data show that hot spring sinters can preserve biomolecules from the local microbial community, and that crystallinity rather than age may be the determining factor in their preservation. This research provides support for the exploration for biomolecules in opaline silica deposits on Mars.

Original languageEnglish
Pages (from-to)537-551
Number of pages15
JournalAstrobiology
Volume20
Issue number4
DOIs
Publication statusPublished - Apr 2020

Keywords

  • Hot springs
  • Sinter
  • Biomarkers
  • Cyanobacteria

Fingerprint Dive into the research topics of 'Biomolecules from fossilized hot spring sinters: implications for the search for life on mars'. Together they form a unique fingerprint.

  • Cite this

    Teece, B. L., George, S. C., Djokic, T., Campbell, K. A., Ruff, S. W., & Van Kranendonk, M. J. (2020). Biomolecules from fossilized hot spring sinters: implications for the search for life on mars. Astrobiology, 20(4), 537-551. https://doi.org/10.1089/ast.2018.2018