| 73438 |
Creator |
40460ef510a4d7308171cd187861768c |
| 73438 |
Creator |
9ce5cfe8f005abcb2055a68594deb0c9 |
| 73438 |
Creator |
ext-0310c83ef7d0ff5957ee04906fcfb285 |
| 73438 |
Creator |
ext-3d88a72b570fbcda0840f96e90f93785 |
| 73438 |
Creator |
ext-93597d28448523b224050a99bc940df8 |
| 73438 |
Creator |
ext-f7afe0bb3caeebaa37fd2dc89d8a3f55 |
| 73438 |
Date |
2018-09-15 |
| 73438 |
Is Part Of |
p0012821X |
| 73438 |
Is Part Of |
repository |
| 73438 |
abstract |
Silica-rich hydrothermal fluids that experience freezing temperatures precipitate
cryogenic opal-A (COA) within ice-bound brine channels. We investigated cryogenic
silicification as a novel preservation pathway for chemo- and photo-lithotrophic Bacteria
and Archaea. We find that the co-partitioning of microbial cells and silica into brine
channels causes microorganisms to become fossilised in COA. Rod- and coccoidal-form
Bacteria and Archaea produce numerous cell casts on COA particle surfaces, while Chloroflexus
filaments are preserved inside particle interiors. COA particles precipitated from
natural Icelandic hot spring fluids possess similar biomorphic casts, including those
containing intact microbial cells. Biomolecules and inorganic metabolic products are
also captured by COA precipitation, and are detectable with a combination of visible
- shortwave infrared reflectance, FTIR, and Raman spectroscopy. We identify cryogenic
silicification as a newly described mechanism by which microbial biosignatures can
be preserved within silica-rich hydrothermal environments. This work has implications
for the interpretation of biosignatures in relic hydrothermal settings, and for life-detection
on Mars and Enceladus, where opaline silica indicative of hydrothermal activity has
been detected, and freezing surface conditions predominate. |
| 73438 |
authorList |
authors |
| 73438 |
status |
peerReviewed |
| 73438 |
uri |
http://data.open.ac.uk/oro/document/1260673 |
| 73438 |
uri |
http://data.open.ac.uk/oro/document/1260674 |
| 73438 |
uri |
http://data.open.ac.uk/oro/document/1260681 |
| 73438 |
uri |
http://data.open.ac.uk/oro/document/1260682 |
| 73438 |
uri |
http://data.open.ac.uk/oro/document/1260683 |
| 73438 |
uri |
http://data.open.ac.uk/oro/document/1260684 |
| 73438 |
uri |
http://data.open.ac.uk/oro/document/1261161 |
| 73438 |
volume |
498 |
| 73438 |
type |
AcademicArticle |
| 73438 |
type |
Article |
| 73438 |
label |
Fox-Powell, Mark ; Channing, Alan; Applin, Daniel; Cloutis, Ed; Preston, Louisa and
Cousins, Claire (2018). Cryogenic silicification of microorganisms in hydrothermal
fluids. Earth and Planetary Science Letters, 498 pp. 1–8. |
| 73438 |
Title |
Cryogenic silicification of microorganisms in hydrothermal fluids |
| 73438 |
in dataset |
oro |