Home > Research > Publications & Outputs > Controls of Sluggish, CO2-promoted, Hematite an...
View graph of relations

Controls of Sluggish, CO2-promoted, Hematite and K-feldspar dissolution kinetics in sandstones

Research output: Contribution to Journal/MagazineJournal articlepeer-review

Published

Standard

Controls of Sluggish, CO2-promoted, Hematite and K-feldspar dissolution kinetics in sandstones. / Wigley, Max; Dubacq, Benoit; Kampman, Niko et al.
In: Earth and Planetary Science Letters, Vol. 362, 15.01.2013, p. 76–87.

Research output: Contribution to Journal/MagazineJournal articlepeer-review

Harvard

Wigley, M, Dubacq, B, Kampman, N & Bickle, M 2013, 'Controls of Sluggish, CO2-promoted, Hematite and K-feldspar dissolution kinetics in sandstones', Earth and Planetary Science Letters, vol. 362, pp. 76–87. https://doi.org/10.1016/j.epsl.2012.11.045

APA

Vancouver

Wigley M, Dubacq B, Kampman N, Bickle M. Controls of Sluggish, CO2-promoted, Hematite and K-feldspar dissolution kinetics in sandstones. Earth and Planetary Science Letters. 2013 Jan 15;362:76–87. doi: 10.1016/j.epsl.2012.11.045

Author

Wigley, Max ; Dubacq, Benoit ; Kampman, Niko et al. / Controls of Sluggish, CO2-promoted, Hematite and K-feldspar dissolution kinetics in sandstones. In: Earth and Planetary Science Letters. 2013 ; Vol. 362. pp. 76–87.

Bibtex

@article{9dafc74ce65b4334a4709e080f2dbb04,
title = "Controls of Sluggish, CO2-promoted, Hematite and K-feldspar dissolution kinetics in sandstones",
abstract = "CO2 sequestration is regarded as an important strategy for reducing anthropogenic CO2 emissions. Both the nature and rate of fluid–mineral reactions in CO2–water–rock systems are crucial, yet poorly constrained, parameters in understanding the fate of CO2 injected in geological formations. This study models reactions and reaction rates in an exhumed CO2-charged aquifer where CO2-rich brines have bleached red sandstones by dissolution of hematite grain coatings. We show that the vertical movement of the reaction front is dominated by diffusion and this allows calculation of reaction rates for the dissolution of hematite grain coatings and K-feldspar. Using mineral surface areas calculated from BET measurements, we estimate K-feldspar dissolution rates of View the MathML source; and hematite reaction rates of View the MathML source. The rates for K-feldspar are lower than previous, experimentally derived, estimates of K-feldspar dissolution rates by 1–2 orders of magnitude, likely explained by the proximity of the natural system to equilibrium. The inferred hematite reaction rates are 5–6 orders of magnitude slower than laboratory experiments and appear to be controlled by the chemical gradients imposed by the more sluggish K-feldspar dissolution. As the majority of potentially mobile trace metals are hosted in iron-oxide grain coatings, we argue that the rate of contaminant mobilization by CO2-charged brines will be lower than suggested by laboratory experiments.",
keywords = "CO2, kinetics, hematite, K-feldspar, Green River, Trace metals",
author = "Max Wigley and Benoit Dubacq and Niko Kampman and Mike Bickle",
year = "2013",
month = jan,
day = "15",
doi = "10.1016/j.epsl.2012.11.045",
language = "English",
volume = "362",
pages = "76–87",
journal = "Earth and Planetary Science Letters",
issn = "0012-821X",
publisher = "Elsevier Science B.V.",

}

RIS

TY - JOUR

T1 - Controls of Sluggish, CO2-promoted, Hematite and K-feldspar dissolution kinetics in sandstones

AU - Wigley, Max

AU - Dubacq, Benoit

AU - Kampman, Niko

AU - Bickle, Mike

PY - 2013/1/15

Y1 - 2013/1/15

N2 - CO2 sequestration is regarded as an important strategy for reducing anthropogenic CO2 emissions. Both the nature and rate of fluid–mineral reactions in CO2–water–rock systems are crucial, yet poorly constrained, parameters in understanding the fate of CO2 injected in geological formations. This study models reactions and reaction rates in an exhumed CO2-charged aquifer where CO2-rich brines have bleached red sandstones by dissolution of hematite grain coatings. We show that the vertical movement of the reaction front is dominated by diffusion and this allows calculation of reaction rates for the dissolution of hematite grain coatings and K-feldspar. Using mineral surface areas calculated from BET measurements, we estimate K-feldspar dissolution rates of View the MathML source; and hematite reaction rates of View the MathML source. The rates for K-feldspar are lower than previous, experimentally derived, estimates of K-feldspar dissolution rates by 1–2 orders of magnitude, likely explained by the proximity of the natural system to equilibrium. The inferred hematite reaction rates are 5–6 orders of magnitude slower than laboratory experiments and appear to be controlled by the chemical gradients imposed by the more sluggish K-feldspar dissolution. As the majority of potentially mobile trace metals are hosted in iron-oxide grain coatings, we argue that the rate of contaminant mobilization by CO2-charged brines will be lower than suggested by laboratory experiments.

AB - CO2 sequestration is regarded as an important strategy for reducing anthropogenic CO2 emissions. Both the nature and rate of fluid–mineral reactions in CO2–water–rock systems are crucial, yet poorly constrained, parameters in understanding the fate of CO2 injected in geological formations. This study models reactions and reaction rates in an exhumed CO2-charged aquifer where CO2-rich brines have bleached red sandstones by dissolution of hematite grain coatings. We show that the vertical movement of the reaction front is dominated by diffusion and this allows calculation of reaction rates for the dissolution of hematite grain coatings and K-feldspar. Using mineral surface areas calculated from BET measurements, we estimate K-feldspar dissolution rates of View the MathML source; and hematite reaction rates of View the MathML source. The rates for K-feldspar are lower than previous, experimentally derived, estimates of K-feldspar dissolution rates by 1–2 orders of magnitude, likely explained by the proximity of the natural system to equilibrium. The inferred hematite reaction rates are 5–6 orders of magnitude slower than laboratory experiments and appear to be controlled by the chemical gradients imposed by the more sluggish K-feldspar dissolution. As the majority of potentially mobile trace metals are hosted in iron-oxide grain coatings, we argue that the rate of contaminant mobilization by CO2-charged brines will be lower than suggested by laboratory experiments.

KW - CO2

KW - kinetics

KW - hematite

KW - K-feldspar

KW - Green River

KW - Trace metals

UR - http://www.scopus.com/inward/record.url?scp=84871777152&partnerID=8YFLogxK

U2 - 10.1016/j.epsl.2012.11.045

DO - 10.1016/j.epsl.2012.11.045

M3 - Journal article

AN - SCOPUS:84871777152

VL - 362

SP - 76

EP - 87

JO - Earth and Planetary Science Letters

JF - Earth and Planetary Science Letters

SN - 0012-821X

ER -