Tourmaline B-isotopes as tracers of fluid sources in silicified Palaeoarchaean oceanic crust of the Mendon Formation, Barberton greenstone belt, South Africa

Farber, Katja; Dziggel, Annika; Trumbull, Robert B.; Meyer, Franz Michael; Wiedenbeck, Michael

doi:10.1016/j.chemgeo.2015.10.009

Cited by 18 publications

(9 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5), consistent with, but not exclusive to, modern filamentous microorganisms forming biofilms. The excellent preservation of these features is thought to be due to a combination of very early silicification, low tectonic strain, and the low temperature of post-depositional hydrothermal overprinting (<150°C) in the interior part of the Barberton Greenstone Belt 19,25 . Raman microspectroscopy demonstrates that the carbonaceous laminae of both the terrestrial and marine mats 19 are composed of organic carbon that has experienced similar peak temperatures of ~365°C (see Methods), consistent with the metamorphic grade of lower greenschist facies established by mineralogical indicators 26 and previous Raman-based estimates of regional peak metamorphic temperatures for the central part of the BGB 27 (Fig.…”

Section: Terrestrial Microbial Mats In Fluvial Sandstonesmentioning

confidence: 99%

Microbial life and biogeochemical cycling on land 3,220 million years ago

et al. 2018

View full text Add to dashboard Cite

The colonization of emergent continental landmass by microbial life was an evolutionary step of paramount importance in Earth history. Here we report direct fossil evidence for life on land 3,220 Myr ago in the form of terrestrial microbial mats draping fluvial conglomerates and gravelly sandstones of the Moodies Group, South Africa. Combined field, petrographic, carbon isotope, and Raman spectroscopic analyses confirm the synsedimentary origin and biogenicity of these unique fossil mats as well as their fluvial habitat. The carbon isotope composition of organic matter (d 13 Corg) from these mats define a narrow range centered on -21‰, in contrast to fossil mats of marine origin from nearby tidal deposits that show d 13 Corg values as low as -34‰. Bulk nitrogen isotope compositions (2

show abstract

Section: Terrestrial Microbial Mats In Fluvial Sandstonesmentioning

confidence: 99%

Microbial life and biogeochemical cycling on land 3,220 million years ago

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Also supporting the possible presence of lüneburgite on the early Earth, borate-containing tourmaline crystals [40] are found in a hot spring deposit in which the oldest stromatolites are found, the 3.5 Ga Dresser Formation. [41] More generally, borate is concentrated in residual igneous melts, comes to the surface of igneous formations, is easily weathered, and is likely concentrated in the hydrosphere, all processes likely on dry land on early Earth.…”

Section: +mentioning

confidence: 96%

Evaporite Borate‐Containing Mineral Ensembles Make Phosphate Available and Regiospecifically Phosphorylate Ribonucleosides: Borate as a Multifaceted Problem Solver in Prebiotic Chemistry

et al. 2016

View full text Add to dashboard Cite

RNA is currently thought to have been the first biopolymer to support Darwinian natural selection on Earth. However, the phosphate esters in RNA and its precursors, and the many sites at which phosphorylation might occur in ribonucleosides under conditions that make it possible, challenge prebiotic chemists. Moreover, free inorganic phosphate may have been scarce on early Earth owing to its sequestration by calcium in the unreactive mineral hydroxyapatite. Herein, it is shown that these problems can be mitigated by a particular geological environment that contains borate, magnesium, sulfate, calcium, and phosphate in evaporite deposits. Actual geological environments, reproduced here, show that Mg and borate sequester phosphate from calcium to form the mineral lüneburgite. Ribonucleosides stabilized by borate mobilize borate and phosphate from lüneburgite, and are then regiospecifically phosphorylated by the mineral. Thus, in addition to guiding carbohydrate pre-metabolism, borate minerals in evaporite geoorganic contexts offer a solution to the phosphate problem in the "RNA first" model for the origins of life.

show abstract

“…Also supporting the possible presence of lüneburgite on the early Earth, borate-containing tourmaline crystals [40] are found in ahot spring deposit in which the oldest stromatolites are found, the 3.5 Ga Dresser Formation. [41] More generally, borate is concentrated in residual igneous melts,comes to the surface of igneous formations,i se asily weathered, and is likely concentrated in the hydrosphere,all processes likely on dry land on early Earth.…”

mentioning

confidence: 99%

Evaporite Borate‐Containing Mineral Ensembles Make Phosphate Available and Regiospecifically Phosphorylate Ribonucleosides: Borate as a Multifaceted Problem Solver in Prebiotic Chemistry

et al. 2016

View full text Add to dashboard Cite

RNAi sc urrently thought to have been the first biopolymer to support Darwinian natural selection on Earth. However,the phosphate esters in RNAand its precursors,and the many sites at which phosphorylation might occur in ribonucleosides under conditions that make it possible,c hallenge prebiotic chemists.M oreover,f ree inorganic phosphate may have been scarce on early Earth owing to its sequestration by calcium in the unreactive mineral hydroxyapatite.Herein, it is shown that these problems can be mitigated by ap articular geological environment that contains borate,m agnesium, sulfate,c alcium, and phosphate in evaporite deposits.A ctual geological environments,reproduced here,show that Mg 2+ and borate sequester phosphate from calcium to form the mineral lüneburgite.R ibonucleosides stabilized by borate mobilize borate and phosphate from lüneburgite,a nd are then regiospecifically phosphorylated by the mineral. Thus,inaddition to guiding carbohydrate pre-metabolism, borate minerals in evaporite geoorganic contexts offer asolution to the phosphate problem in the "RNAfirst" model for the origins of life.

show abstract

Tourmaline B-isotopes as tracers of fluid sources in silicified Palaeoarchaean oceanic crust of the Mendon Formation, Barberton greenstone belt, South Africa

Cited by 18 publications

References 75 publications

Microbial life and biogeochemical cycling on land 3,220 million years ago

Microbial life and biogeochemical cycling on land 3,220 million years ago

Evaporite Borate‐Containing Mineral Ensembles Make Phosphate Available and Regiospecifically Phosphorylate Ribonucleosides: Borate as a Multifaceted Problem Solver in Prebiotic Chemistry

Evaporite Borate‐Containing Mineral Ensembles Make Phosphate Available and Regiospecifically Phosphorylate Ribonucleosides: Borate as a Multifaceted Problem Solver in Prebiotic Chemistry

Contact Info

Product

Resources

About