Geochemical self-organization of olivine-grade contact metamorphosed chert nodules in dolomite marble, Kilchrist, Skye

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Authors:Holness, M. B.
Author Affiliations:Primary:
University of Edinburgh, Department of Geology and Geophysics, Edinburgh, United Kingdom
Volume Title:Journal of Metamorphic Geology
Source:Journal of Metamorphic Geology, 15(6), p.765-775. Publisher: Blackwell, Oxford, United Kingdom. ISSN: 0263-4929
Publication Date:1997
Note:In English. 27 refs.; illus., incl. 2 plates
Summary:Chert nodules in dolostones in the aureole of the Tertiary Beinn an Dubhaich granite have developed mm-scale concentric monomineralic bands of alternating calcite and olivine during breakdown of a diopside core by the reaction 3 Dol + Di = 4 Cal + 2Fo + 2CO2. A simple textural progression from thin (<<<[dollar]I> 1 cm) homogeneous olivine-calcite rims close to the olivine-in isograd, to total replacement of the diopside core by a up to 10 cm thick well-banded rim close to the carbonate-granite contact demonstrates the developmental stages of the texture. Correlation of olivine grain size with band spacing, and a greater olivine grain size in banded compared to homogeneous rims, support pattern development by post-nucleation geochemical self-organization. [P.J.T.]
Subjects:Banded structures; Calcite; Carbonates; Chemical reactions; Chemically precipitated rocks; Chert; Concretions; Contact metamorphism; Dolomite; Geochemistry; Grain size; Marbles; Metamorphic rocks; Metamorphism; Models; Nesosilicates; Olivine; Olivine group; Orthosilicates; Secondary structures; Sedimentary rocks; Sedimentary structures; Self-organization; Silicates; Textures; Thermal history; Europe; Great Britain; Hebrides; Highland region Scotland; Inner Hebrides; Inverness-shire Scotland; Isle of Skye; Scotland; United Kingdom; Western Europe
Coordinates:N570000 N574000 W0054000 W0064500
Abstract Numbers:98M/3202
Record ID:1998001576
Copyright Information:GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Mineralogical Abstracts, United Kingdom, Twickenham, United Kingdom
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