{"thcode":2,"term":{"code":464,"name":"geology","parent":291,"scope":"Study of the planet earth, its composition, structure, physical and chemical processes, and history since its origin."},"uf":[{"name":"subsurface 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."}}],"bt":[{"code":291,"name":"earth sciences","parent":1019,"scope":"Broad term for all science related to the study of the earth."},{"code":1019,"name":"sciences","parent":1,"scope":"Major educational fields, fields of study, and professional groupings within USGS."},{"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":312,"name":"economic geology","parent":464,"scope":"Scientific study of the formation, location, and use of marketable geologic materials including fuels, metals, minerals, and water."},{"code":438,"name":"geochronology","parent":464,"scope":"Study of the age of the earth by dating geological formations, rocks, and fossils."},{"code":468,"name":"geomorphology","parent":464,"scope":"Branch of geology dealing with surface land features and the processes that create and change them."},{"code":554,"name":"hydrogeology","parent":464,"scope":"Study of subsurface waters and geologic aspects of surface waters."},{"code":706,"name":"marine geology","parent":464,"scope":"Branch of geology concerned with the composition, geologic history, and earth processes of the ocean floor and the continental margin."},{"code":747,"name":"mineralogy","parent":464,"scope":"Branch of earth sciences concerned with the study of naturally occurring inorganic elements or compounds."},{"code":883,"name":"petrology","parent":464,"scope":"Branch of earth sciences concerned with the origin, structure, alteration, and composition of rocks."},{"code":1037,"name":"sedimentology","parent":464,"scope":"Branch of earth sciences concerned with the study of the origin, composition, transport, and changes of materials deposited by water, wind, or ice."},{"code":1104,"name":"stratigraphy","parent":464,"scope":"Branch of geology concerned with the study of the formation, composition, ordering in time, and arrangement in space of stratified rocks."},{"code":1117,"name":"structural geology","parent":464,"scope":"Branch of geology concerned with the distribution, position, shape, and internal structure of rocks."},{"code":1289,"name":"volcanology","parent":464,"scope":"The branch of geology that deals with volcanism and the processes involved in magma flow and eruption through a vent in the earth's surface."}],"rt":[{"code":281,"name":"drilling and coring","parent":379,"scope":"Cutting into the subsurface, for example into underground strata, ice, or a tree trunk, to remove material for examination. Intended for broad use wherever coring is done. The combination of this term with other terms will convey the context of the activity."},{"code":288,"name":"earth history","parent":455,"scope":"The structural and compositional changes that the earth has undergone from its formation. Use for discussions of the whole earth (or large sections of it) instead of regional studies."},{"code":337,"name":"engineering geology","parent":339,"scope":"Branch of geology involved in the application of soil and rock mechanics, natural hazards, and other geological studies to the practice of engineering and construction."},{"code":455,"name":"geologic history","parent":287,"scope":"Record (and inferred reconstruction) of the origin and development of the earth since its formation."},{"code":1748,"name":"geologic maps","parent":700,"scope":"Maps depicting geological characteristics of the earth's surface, including lithology, geologic structure, age, and the results of crustal processes. Used where the product includes a depiction of the map as a whole, not for data sets that could be used to create a map."},{"code":451,"name":"geologic processes","parent":101,"scope":"All types of processes involving geological structures."},{"code":727,"name":"metamorphism (geological)","parent":451,"scope":"Process by which rocks are altered in composition and texture by extreme heat, high pressure, or the action of chemicals."}]}