| Text Description: |
Flow overlying 94SJP94 on the west side of Goat Creek. Outcrop weathers into large plates and consists of a lower rubble zone that grades up into a 10-15’ thick massive zone with an overlying vesicular zone. Fine grained, vesicular, holocrystalline, seriate porphyritic with a matrix of mesostasis, opaque, plagioclase, clinopyroxene and olivine. An inclusion of plagioclase, mesostasis and pyroxene is present. Xenolithic quartz grains up to 0.6 mm are surrounded by a corona of small clinopyroxene crystals. Plagioclase phenocrysts (An36 - An61) are up to 2.5 mm and large grains have sieve textured zones with resorbed edges. Olivine phenocrysts are up to 0.6 mm and occasionally have thin dark rims and resorption embayments. Clinopyroxene phenocrysts are up to 0.25 mm. There may be some orthopyroxene? present. |