Evolution of H2O content in deforming quartz aggregates: An experimental study

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F24%3A10486750" target="_blank" >RIV/00216208:11310/24:10486750 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=7CXveyPDfj" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=7CXveyPDfj</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jsg.2023.105029" target="_blank" >10.1016/j.jsg.2023.105029</a>

Result language

angličtina

Original language name

Evolution of H2O content in deforming quartz aggregates: An experimental study

Original language description

Deformation experiments were carried out on pure quartzite samples (&gt;99% quartz) with a grain size of similar to 200 um from Tana, Northern Norway. Deformation conditions were 900 °C, 0.1 wt% H2O added, strain rate ~1 x 10(-6) s(-1) at variable confining pressures from 600 to 2000 MPa. Detailed FTIR measurements of H2O indicate that the H2O content in the grain boundary region is higher than that inside quartz grains. Hydrostatic treatment and deformation at the chosen temperature and pressure conditions lead to further H2O loss from grain interiors and H2O increase in the grain boundary region. Varying the confining pressure does not have an observable effect on the H2O transfer from grains to the grain boundary region. The 3585 cm(-1) absorption band increases systematically with increasing confining pressure. As this band is associated with OH in dislocations, the increase may indicate an increased dislocation density with increasing pressure. The triplet of 3317, 3375 and 3438 cm(-1) associated with Al-content in quartz increases in the grain boundary region indicating an exchange of H+ together with Al(3+) for Si(4+). The Al and H exchange suggest dissolution-precipitation processes in the grain boundary region facilitating the movement of the quartz grain boundaries (grain boundary migration). The H2O in the grain boundary region will be important for enhancing grain boundary migration and thus recrystallization processes during deformation.

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

—

OECD FORD branch

10505 - Geology

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2024

Confidentiality

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

Name of the periodical

Journal of Structural Geology

ISSN

0191-8141

e-ISSN

1873-1201

Volume of the periodical

178

Issue of the periodical within the volume

January

Country of publishing house

GB - UNITED KINGDOM

Number of pages

19

Pages from-to

105029

UT code for WoS article

001164230500001

EID of the result in the Scopus database

2-s2.0-85180478386