{"thcode":2,"term":{"code":590,"name":"inner core (earth)","parent":211,"scope":"The solid interior part of the earth's core, presumed to be composed principally of iron with an alloy of about 10 percent oxygen, sulfur, or nickel, or perhaps some combination of these three elements.  The inner core is about 1221 kilometers thick."},"uf":[],"bt":[{"code":211,"name":"core (earth)","parent":292,"scope":"The superdense center of the earth composed of two layers: a liquid outer layer and a solid inner core of metallic iron-nickel alloy."},{"code":292,"name":"earth structure","parent":287,"scope":"Major interior structural features of the planet earth."},{"code":287,"name":"earth characteristics","parent":1174,"scope":"The measurable, definable properties and features of the earth."},{"code":1174,"name":"topics","parent":1,"scope":"Themes, subjects, and concerns for which USGS information resources are relevant."},{"code":1,"name":"Categories","parent":null,"scope":"Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."}],"nt":[],"rt":[{"code":470,"name":"geophysics","parent":291,"scope":"Branch of geology studying the physical characteristics and phenomena of the earth and its atmosphere."}]}