Physical weathering by glaciers enhances silicon mobilisation and isotopic fractionation

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F21%3A10441903" target="_blank" >RIV/00216208:11310/21:10441903 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6bKeloNYQu" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6bKeloNYQu</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.7185/geochemlet.2126" target="_blank" >10.7185/geochemlet.2126</a>

Result language

angličtina

Original language name

Physical weathering by glaciers enhances silicon mobilisation and isotopic fractionation

Original language description

Glacial meltwaters export substantial quantities of dissolved and dissolvable amorphous silicon (DSi and ASi), providing an essential nutrient for downstream diatoms. Evidence suggests that glacially exported DSi is isotopically light compared to DSi in non-glaciated rivers. However, the isotopic fractionation mechanisms are not well constrained, indicating an important gap in our understanding of processes in the global Si cycle. We use rock crushing experiments to mimic subglacial physical erosion, to provide insight into subglacial isotope fractionation. Isotopically light DSi [δ(30)SiDSi] released following initial dissolution of freshly ground mineral surfaces (down to -2.12 +/- 0.02 promile) suggests mechanochemical reactions induce isotopic fractionation, explaining the low δ(30)SiDSi composition of subglacial runoff. ASi with a consistent isotopic composition is present in all mechanically weathered samples, but concentrations are elevated in samples that have undergone more intense physical grinding. These experiments illustrate the critical role of physical processes in driving isotopic fractionation and biogeochemical weathering in subglacial environments. Understanding perturbations in high latitude Si cycling under climatic change will likely depend on the response of mechanochemical weathering to increased glacial melt.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10505 - Geology

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2021

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Geochemical Perspectives Letters

ISSN

2410-339X

e-ISSN

—

Volume of the periodical

19

Issue of the periodical within the volume

October

Country of publishing house

FR - FRANCE

Number of pages

6

Pages from-to

7-12

UT code for WoS article

000770975400002

EID of the result in the Scopus database

2-s2.0-85126101477