{"thcode":2,"term":{"code":1050,"name":"seismology","parent":470,"scope":"Branch of earth sciences concerned with the study of earthquakes and man-induced seismic waves."},"uf":[{"name":"earthquake seismology","usewith":{"code":299,"name":"earthquake occurrences","parent":304,"scope":"Time, location, severity, and mechanism of earthquake events, including the frequency and history of events in a given area."}},{"name":"engineering seismology","usewith":{"code":339,"name":"engineering sciences","parent":1019,"scope":"Sciences involved in the application of scientific and mathematical principles to construction, machinery, mechanical design, mining and manufacturing processes and other practical activities."}},{"name":"exploration seismology","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."}}],"bt":[{"code":470,"name":"geophysics","parent":291,"scope":"Branch of geology studying the physical characteristics and phenomena of the earth and its atmosphere."},{"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":862,"name":"paleoseismology","parent":1050,"scope":"Branch of seismology concerned with ancient earthquakes.  Clues which indicate seismic activities in the geologic past are used  to date and determine the effects of those earthquakes."}],"rt":[{"code":299,"name":"earthquake occurrences","parent":304,"scope":"Time, location, severity, and mechanism of earthquake events, including the frequency and history of events in a given area."},{"code":304,"name":"earthquakes","parent":451,"scope":"Ground shaking caused by the sudden release of accumulated strain by an abrupt shift of rock along a fracture in the earth or by volcanic or magmatic activity, or other sudden stress changes in the earth."},{"code":1042,"name":"seismic methods","parent":375,"scope":"Procedures used to record and study earthquakes or earth vibrations including those that are artificially induced."},{"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."},{"code":1145,"name":"tectonic processes","parent":451,"scope":"The structural forces affecting the deformation, uplift, and movement of the earth's crust."},{"code":1169,"name":"tiltmeter measurement","parent":375,"scope":"Determination of tiny changes in the slope angle or tilt of the ground in order to monitor deformation caused by moving magma. Instruments detect variations in a liquid level or in the position of a pendulum."},{"code":1195,"name":"tsunamis","parent":822,"scope":"Sea waves generated by submarine earthquakes, volcanic eruptions, or landslides, which are generally imperceptible in deep water but may be very destructive when striking the shoreline."},{"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."}]}