{"thcode":2,"term":{"code":1005,"name":"rocks and deposits","parent":287,"scope":"Solid masses that make up the earth's crust as well as accumulations of materials. Use for major rock types and unconsolidated deposits. For deposits of economic value, see related terms."},"uf":[{"name":"crystals","usewith":false},{"name":"lithologic maps","usewith":{"code":700,"name":"maps and atlases","parent":808,"scope":"Representation, usually on a flat surface, of a part or whole of the Earth or other parts of the universe.  Collections of maps linked digitally or bound together in a book are called atlases."}},{"name":"lithology","usewith":false},{"name":"rock composition","usewith":false}],"bt":[{"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":[{"code":414,"name":"fossils","parent":1005,"scope":"Recognizable remains such as bones, shells, leaves, burrows, impressions, or tracks of past life on the earth."},{"code":572,"name":"igneous rocks","parent":1005,"scope":"Rocks formed from melted rock that has cooled and solidified."},{"code":725,"name":"metamorphic rocks","parent":1005,"scope":"Sedimentary or igneous rocks which have undergone such intense changes in temperature, pressure, structural stress, or chemical environment that they are transformed into denser rocks."},{"code":2043,"name":"mineral deposits","parent":1005,"scope":"Deposits in which particular minerals are concentrated, typically noticed and studied if the minerals have economic value."},{"code":1370,"name":"permafrost","parent":1005,"scope":"Rocks and deposits in which the interstitial waters remain perennially frozen."},{"code":1804,"name":"petroleum","parent":1005,"scope":"Naturally occurring hydrocarbons, typically fluid or gas, often of economic use.  Includes oil, natural gas, and asphaltic compounds found in tar sands and oil shales."},{"code":1035,"name":"sedimentary rocks","parent":1005,"scope":"Rocks formed by the consolidation of loose, uncemented pieces of sediments."},{"code":1199,"name":"unconsolidated deposits","parent":1005,"scope":"Loosely bound sediments such as sand, gravel, and silt which tend to accumulate in low areas or valleys."}],"rt":[{"code":132,"name":"building stone resources","parent":798,"scope":"Deposits of rocks used in construction, including crushed stone and dimension stone. Dimension stone includes limestone and granite, quarried in large blocks, and shaped in cubes, panels and other forms."},{"code":667,"name":"lithosphere","parent":219,"scope":"The solid outer zone of the earth comprising the crust and the upper layer of the mantle."},{"code":730,"name":"meteorites","parent":900,"scope":"Masses of rock or metal from space that reach the earth's surface without burning up.  Use for 'meteors' or 'meteoroids' as well as 'meteorites'. USGS is more likely to have information about 'meteorites' since these are objects found on the earth."},{"code":880,"name":"petrography","parent":619,"scope":"Use of optical microscopy for the description and classification of rocks."},{"code":883,"name":"petrology","parent":464,"scope":"Branch of earth sciences concerned with the origin, structure, alteration, and composition of rocks."}]}