| Text Description: |
Approximately 3’ thick dike, trending N65°E, that forms a wall-like outcrop on the top of Site 2. This dike cross-cuts dike 93SJP32 and intrudes silicic material of Dome A. Fine-grained, hypocrystalline, intersertal, intergranular, seriate porphyritic with a matrix of brown glass, opaque, plagioclase, clinopyroxene and red alteration patches. Plagioclase phenocrysts (An33 - An60) are up to 3.4 mm and have sieve textured cores, rare resorption embayments, complex zoning with prussian blue extinction, melt inclusions, and a few have orthopyroxene inclusions. Orthopyroxene phenocrysts are 0.9-0.15 mm and some have clinopyroxene rims and large melt inclusions. Clinopyroxene phenocrysts are up to 0.8 mm and some are twinned. |