{"thcode":2,"term":{"code":248,"name":"diagenesis","parent":451,"scope":"Chemical, physical, and biological changes in sediment during and after its conversion to rock (lithification)."},"uf":[],"bt":[{"code":451,"name":"geologic processes","parent":101,"scope":"All types of processes involving geological structures."},{"code":101,"name":"biological and physical processes","parent":1174,"scope":"All continuing activities, functions, and phenomena associated with organisms and non-living matter."},{"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":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."}]}