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| Titel |
Grain growth kinetics of carbonates: Implications for rheology and closure temperature |
| VerfasserIn |
J. Newman, A. K. Kronenberg, W. Lamb, N. E. Davis, P. Wheelock |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250019901
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| Zusammenfassung |
| Grain sizes of rocks influence the rates at which deformation, diffusional exchange, and
reaction occur. In turn, grain growth kinetics depend on grain boundary mobilities that are
affected by composition, solute segregation, porosity and secondary phases at grain
boundaries. In this study, we explore the rates of grain growth of stoichiometric dolomite
(CaMg(CO3)2), calcite (CaCO3), and magnesite (MgCO3) at temperatures T = 700 - 800oC
and confining pressure Pc = 300 MPa (effective Pe = Pc - PCO2 = 170 - 270 MPa). Dry,
fine-grained aggregates of the three carbonates were synthesized from high purity powders by
hot isostatic pressing (T = 600oC, Pc = 300 MPa, for 9 hours to 5 days). Initial mean grain
sizes of the three hot isostatically pressed carbonates were 1.4, 17, and 1.1 μm,
respectively, for CaMg(CO3)2, CaCO3, and MgCO3, with porosities of 2, |
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