Figure F16. Photomicrographs showing plagioclase phenocrysts. A. Plagioclase megacryst with inclusion of olivine (Sample 197-1205A-15R-2, 138-140 cm) (cross-polarized light; field of view = 5 mm; photomicrograph 1205A-211). B. Rounded plagioclase phenocryst with resorption rim (Sample 197-1205A-13R-3, 27-29 cm) (cross-polarized light; field of view = 1.25 mm; photomicrograph 1205A-206).