{"thcode":2,"term":{"code":1042,"name":"seismic methods","parent":375,"scope":"Procedures used to record and study earthquakes or earth vibrations including those that are artificially induced."},"uf":[{"name":"seismic exploration","usewith":{"code":774,"name":"natural resource exploration","parent":1174,"scope":"Techniques for locating deposits or stocks of useful minerals, water, and other resources using reconnaissance or instrumental methods."}},{"name":"seismic imaging","usewith":false},{"name":"seismic profiles","usewith":false},{"name":"seismograms","usewith":false},{"name":"seismometry","usewith":false}],"bt":[{"code":375,"name":"field inventory and monitoring","parent":376,"scope":"Repeated observation or sampling at a site, on a scheduled or event basis, for study and analysis.  In general, this category excludes sampling programs in which materials are obtained in the field and brought back to a laboratory for study and analysis."},{"code":376,"name":"field methods","parent":734,"scope":"Research procedures and instrumental means to measure, collect data and samples, and observe in the natural areas where the materials, phenomena, structures, or species being studied occur."},{"code":734,"name":"methods","parent":1,"scope":"Techniques, methods, procedures, or strategies for research, management, collection, or analysis of scientific information in 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":1043,"name":"seismic networking","parent":1042,"scope":"Deploying, operating, and maintaining groups and arrays of instruments for detecting and describing local movements of the earth."},{"code":1045,"name":"seismic reflection methods","parent":1042,"scope":"Geophysical technique to study the subsurface of the earth using sound waves induced by explosives, vibrating devices, or percussive equipment.  The reflections of the sound waves from the boundaries of different rocks are measured."},{"code":1047,"name":"seismic refraction methods","parent":1042,"scope":"Geophysical technique to study the subsurface of the earth by generating compressional waves by means of hammering or explosive methods. The variations in velocity of the waves traveling through rocks or geological layers are measured."}],"rt":[{"code":981,"name":"remote sensing","parent":734,"scope":"Acquiring information about a natural feature or phenomenon, such as the Earth's surface, without actually being in contact with it. USGS remote sensing is usually carried out with airborne or spaceborne sensors or cameras."},{"code":1050,"name":"seismology","parent":470,"scope":"Branch of earth sciences concerned with the study of earthquakes and man-induced seismic waves."}]}