| Text Description: |
Approximately 2 m thick, subvertical dike trending N45E and cutting through Dome A at Site 2. Fine-grained, seriate, pilotaxitic, very altered, intergranular, hypocrystalline with a matrix of alteration, opaque, plagioclase, lath shaped clinopyroxene, mesostasis, and a very small amount of brown glass. Plagioclase phenocrysts (An28-An58) are 1.35-0.05 mm, sieve textured cores are common; most have normal zoning; some have oscillatory zoning. Clinopyroxene phenocrysts have two populations, 0.6 -0.2 mm and 0.15-0.5 (lath shaped). Olivine phenocrysts are 1.9 - 0.15 mm; most are completely altered, with only a few cores remaining; some have opaque inclusions. |