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3.10 · Grain Boundary Area Reduction (GBAR) 55
Box 3.9 Continued
Fig. B.3.1. Schematic presentation of fabric nomenclature for the shape of grains and grain aggregates. (After Moore 1970)
1961; Evans et al. 2001). If grains of different size are sur- ones increase. The theory of Ostwald ripening is mostly
rounded by a fluid, small grains with a highly curved sur- applied in igneous petrology for development of
face tend to dissolve while large grains with a smaller phenocrysts (Park and Hanson 1999), but also for growth
curvature of the surface grow (×Videos 11.6c–e, 11.10f). of porphyroblasts in metamorphic rocks (Miyazaki 1991;
In this way, smaller grains tend to disappear while larger Carlson 1989).
