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Alkaline vents and steep Na+ gradients from ridge-flank basalts—Implications for the origin and evolution of life

2017; Geological Society of America; Volume: 45; Issue: 12 Linguagem: Inglês

10.1130/g39474.1

1943-2682

R.E. Price, Eric S. Boyd, Tori M. Hoehler, Laura M. Wehrmann, Erlendur Bogason, Hreiðar Þór Valtýsson, Jóhann Örlygsson, Bjarni Gautason, Jan P. Amend,

Microbial Community Ecology and Physiology

Research Article| October 19, 2017 Alkaline vents and steep Na+ gradients from ridge-flank basalts—Implications for the origin and evolution of life Roy Price; Roy Price 1Stony Brook University, SoMAS, Stony Brook, New York 11794, USA Search for other works by this author on: GSW Google Scholar Eric S. Boyd; Eric S. Boyd 2Montana State University, Department of Microbiology and Immunology, Bozeman, Montana 59717, USA Search for other works by this author on: GSW Google Scholar Tori M. Hoehler; Tori M. Hoehler 3NASA Ames Research Center, Moffett Field, California 94035, USA Search for other works by this author on: GSW Google Scholar Laura M. Wehrmann; Laura M. Wehrmann 1Stony Brook University, SoMAS, Stony Brook, New York 11794, USA Search for other works by this author on: GSW Google Scholar Erlendur Bogason; Erlendur Bogason 4Strytan Divecenter, 601 Hjalteyri, Iceland Search for other works by this author on: GSW Google Scholar Hreiðar Þór Valtýsson; Hreiðar Þór Valtýsson 5University of Akureyri, 600 Akureyri, Iceland Search for other works by this author on: GSW Google Scholar Jóhann Örlygsson; Jóhann Örlygsson 5University of Akureyri, 600 Akureyri, Iceland Search for other works by this author on: GSW Google Scholar Bjarni Gautason; Bjarni Gautason 6Iceland Geosurvey, Rangarvellir, 603 Akureyri, Iceland Search for other works by this author on: GSW Google Scholar Jan P. Amend Jan P. Amend 7University of Southern California, Department of Biological Science and Department of Earth Science, Los Angeles, California 90007, USA Search for other works by this author on: GSW Google Scholar Geology (2017) 45 (12): 1135–1138. https://doi.org/10.1130/G39474.1 Article history received: 02 Jul 2017 rev-recd: 22 Sep 2017 accepted: 25 Sep 2017 first online: 19 Oct 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Search Site Citation Roy Price, Eric S. Boyd, Tori M. Hoehler, Laura M. Wehrmann, Erlendur Bogason, Hreiðar Þór Valtýsson, Jóhann Örlygsson, Bjarni Gautason, Jan P. Amend; Alkaline vents and steep Na+ gradients from ridge-flank basalts—Implications for the origin and evolution of life. Geology 2017;; 45 (12): 1135–1138. doi: https://doi.org/10.1130/G39474.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGeology Search Advanced Search Abstract Life may have emerged on early Earth in serpentinizing systems, where ultramafic rocks react with aqueous solutions to generate high levels of dissolved H2 and CH4 and, on meeting seawater, steep redox, ionic, and pH gradients. Most extant life harnesses energy as ion (e.g., H+, Na+) gradients across membranes, and it seems reasonable to suggest that environments with steep ion gradients would have also been important for early life forms. The Strytan Hydrothermal Field (SHF) is a mid-ocean ridge–flank submarine hydrothermal (∼70 °C) vent in Iceland that produces steep Na+ (<3–468 mM) and pH (8.1–10.2) gradients, concomitant with enrichments in methane (0.5–1.4 μM) and hydrogen (0.1–5.2 μM), relative to seawater. Large (up to 55 m) saponite towers create ideal "incubators" similar to other proposed origin-of-life analogs (e.g., Lost City hydrothermal field in the mid-Atlantic). However, the SHF is basalt hosted. We suggest that the observed conditions are generated by (1) plagioclase hydrolysis, coupled with calcite precipitation, and (2) hydration of Mg in pyroxene and olivine in basalt. Along with microbial activity, aqueous reactions of Fe in olivine and pyroxene are possible sources of the observed H2. Although the δ13C-CH4 values were highly variable (−53‰ to −8‰), isotopically heavy CH4 suggests possible abiotic formation or the imprint of methane oxidation. If environments similar to SHF occurred on the early Earth, they should be considered as potential origin-of-life environments. You do not currently have access to this article.