| Text Description: |
Approximately 15' thick flow from near the base of the second andesite package at Site 1 in the Boyden Hills. Fine-grained, vesicular, diktytaxitic, holocrystalline, intergranular, seriate porphyritic with a matrix of mesostasis, opaque, plagioclase, and minor alteration around vesicles. Plagioclase phenocrysts (An27-An56) are up to 1.1 mm, and have occasional sieve textured zones, commonly display normal zoning with occasionally oscillatory zoning. Olivine phenocrysts are up to 0.8 mm with occasionally opaque inclusions, and some alteration. Orthopyroxene phenocrysts are up to 0.5 mm and some have clinopyroxene rims and occasionally opaque inclusions. Clinopyroxene phenocrysts are up to 0.1 mm. |