| Text Description: |
Highest point on the wall-like capping andesite at Site 7. Fine grained, holocrystalline, intergranular, seriate porphyritic with a matrix of mesostasis, opaque, clinopyroxene and alteration. Plagioclase phenocrysts (An37-An61) are up to 0.75 mm and some display sieve textured zones, oscillatory zoning, or have pyroxene inclusions. Orthopyroxene phenocrysts are up to 0.9 mm and frequently have clinopyroxene rims. Clinopyroxene phenocrysts are up to 0.4 mm. An altered phase, up to 0.25 mm, is present. Mode: 39.9% matrix, 47.2% plagioclase, 1.6% clinopyroxene, 4.9% orthopyroxene, 5.8% alteration, 0.6% vesicles. |