{"thcode":2,"term":{"code":2291,"name":"gravity gradient","parent":501,"scope":"Lateral variation of the three-dimensional vector components of gravity, typically measured using airborne sensors."},"uf":[{"name":"gravity gradiometry","usewith":false}],"bt":[{"code":501,"name":"gravitational field (earth)","parent":287,"scope":"Region or space around earth's mass which exerts a force that mutually attracts other masses in proportion to the product of the two masses and the distance between them."},{"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":[],"rt":[{"code":470,"name":"geophysics","parent":291,"scope":"Branch of geology studying the physical characteristics and phenomena of the earth and its atmosphere."},{"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."}]}