{"thcode":4,"term":{"code":"4","name":"Plutonic rock","parent":"0","scope":"A rock formed at considerable depth by crystallization of magma and\/or by chemical alteration.  It is characteristically medium- to coarse-grained, of granitoid texture."},"uf":[],"bt":[{"code":"0","name":"Earth material","parent":null,"scope":"Geologic map unit classification (Bruce R. Johnson) version 6.2: A hierarchical classification of earth materials for digital geologic maps."}],"nt":[{"code":"4.6","name":"Alkalic intrusive rock","parent":"4","scope":"A plutonic rock that contains more sodium and\/or potassium than is required to form feldspar with the available silica."},{"code":"4.1","name":"Aplite","parent":"4","scope":"A light-colored igneous rock characterized by a fine-grained allotriomorphic-granular (i.e. aplitic) texture."},{"code":"4.5","name":"Gabbroid","parent":"4","scope":"A plutonic rock with Q < 20% or F < 10%, P\/(A+P) > 65%, and pl\/(pl+px+ol) between 10 and 90%."},{"code":"4.4","name":"Granitoid","parent":"4","scope":"A general term for all phaneritic igneous rocks dominated by quartz and feldspars."},{"code":"4.8","name":"Intrusive carbonatite","parent":"4","scope":"A plutonic rock composed of at least 50% carbonate minerals."},{"code":"4.3","name":"Pegmatite","parent":"4","scope":"An exceptionally coarse-grained igneous rock, with interlocking crystals, usually found as irregular dikes, lenses, or veins, esp. at the margins of batholiths."},{"code":"4.2","name":"Porphyry","parent":"4","scope":"An igneous rock of any composition that contains conspicuous phenocrysts in a fine-grained groundmass."},{"code":"4.7","name":"Ultramafic intrusive rock","parent":"4","scope":"A general name for plutonic rock with color index (M) greater than or equal to 90..."}],"rt":[]}