Journal cover Journal topic
Solid Earth An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 2.921
IF2.921
IF 5-year value: 3.087
IF 5-year
3.087
CiteScore value: 4.8
CiteScore
4.8
SNIP value: 1.314
SNIP1.314
IPP value: 2.87
IPP2.87
SJR value: 0.993
SJR0.993
Scimago H <br class='widget-line-break'>index value: 38
Scimago H
index
38
h5-index value: 36
h5-index36
Preprints
https://doi.org/10.5194/se-2020-34
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-2020-34
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

  31 Mar 2020

31 Mar 2020

Review status
A revised version of this preprint is currently under review for the journal SE.

Quartz dissolution associated with magnesium silicate hydrate cement precipitation

Lisa de Ruiter1, Anette Eleonora Gunnæs2, Dag Kristian Dysthe1, and Håkon Austrheim1 Lisa de Ruiter et al.
  • 1Physics of Geological Processes (PGP), The Njord Centre, Department of Geosciences and Department of Physics, University of Oslo, PO Box 1048, Blindern, 0136 Oslo, Norway
  • 2Centre for Materials Science and Nanotechnology, Department of Physics, University of Oslo, PO Box 1048, Blindern, 0136 Oslo, Norway

Abstract. Quartz has been replaced by magnesium silicate hydrate cement at the Feragen ultramafic body in south-east Norway. This occurs in deformed and recrystallized quartz grains deposited as glacial till covering part of the ultramafic body. Where the ultramafic body is exposed, weathering leads to high pH (~10), Mg-rich fluids. The dissolution rate of the quartz is about 3 orders of magnitude higher than experimentally derived rate equations suggest under the prevailing conditions. Quartz dissolution and cement precipitation starts at intergranular grain boundaries that act as fluid pathways through the recrystallized quartz. Etch pits are also extensively present at the quartz surfaces as result of preferential dissolution at dislocation sites. Transmission electron microscopy revealed an amorphous silica layer with a thickness of 100–200 nm around weathered quartz grains. We suggest that the amorphous silica is a product of interface-coupled dissolution-precipitation and that the amorphous silica subsequently reacts with the Mg-rich, high pH bulk fluid to precipitate magnesium silicate hydrate cement, allowing for further quartz dissolution and locally a complete replacement of quartz by cement. The cement is the natural equivalent of magnesium silicate hydrate cement (M-S-H), which is currently of interest for nuclear waste encapsulation or for environmentally friendly building cement, but not yet developed for commercial use. This study provides new insights that could potentially contribute in the further development of M-S-H cement.

Lisa de Ruiter et al.

Interactive discussion

Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Topical Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Lisa de Ruiter et al.

Lisa de Ruiter et al.

Viewed

Total article views: 441 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
271 128 42 441 37 41
  • HTML: 271
  • PDF: 128
  • XML: 42
  • Total: 441
  • BibTeX: 37
  • EndNote: 41
Views and downloads (calculated since 31 Mar 2020)
Cumulative views and downloads (calculated since 31 Mar 2020)

Viewed (geographical distribution)

Total article views: 299 (including HTML, PDF, and XML) Thereof 298 with geography defined and 1 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Saved

No saved metrics found.

Discussed

No discussed metrics found.
Latest update: 01 Dec 2020
Publications Copernicus
Download
Short summary
In this work, the formation of natural magnesium silicate hydrate cement has been studied. It forms by the extraordinary fast dissolution of quartz under high pH, Mg-rich conditions that occur in south-east Norway where an ultramafic body is exposed. We studied the cemented rocks and the processes that led to the formation of the cement at the nanoscale. Magnesium silicate hydrate cement might be a low-CO2 alternative for Portland cement.
In this work, the formation of natural magnesium silicate hydrate cement has been studied. It...
Citation