{"thcode":4,"term":{"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..."},"uf":[],"bt":[{"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."},{"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":"4.7.3","name":"Hornblendite","parent":"4.7","scope":"A plutonic rock with M equal to or greater than 90 and hbl\/(hbl+px+ol) greater than 90%."},{"code":"4.7.1","name":"Peridotite","parent":"4.7","scope":"A plutonic rock with M equal to or greater than 90 and ol\/(ol+opx+cpx) greater than 40%"},{"code":"4.7.2","name":"Pyroxenite","parent":"4.7","scope":"A plutonic rock with M equal to or greater than 90 and ol\/(ol+opx+cpx) less than 40%."}],"rt":[]}