noun
porphyritic structure
Technical term in geology referring to a rock texture with large crystals (phenocrysts) in a fine-grained matrix.
この岩石は斑状組織を示している。
This rock shows a porphyritic structure.
Compound of 斑状 (はんじょう, 'spotted' or 'mottled') and 組織 (そしき, 'structure' or 'texture'). The exact historical derivation is uncertain; the term is used in modern geology.