{"thcode":2,"term":{"code":2091,"name":"lakebed acoustic reflectivity","parent":2090,"scope":"Acoustic energy received by a sonar system, providing a measure of the roughness of the lakebed."},"uf":[{"name":"backscatter (lakebed)","usewith":false}],"bt":[{"code":2090,"name":"lakebed characteristics","parent":287,"scope":"Characteristics of the bottom of inland bodies of water."},{"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":2037,"name":"interferometric sonar","parent":1083,"scope":"Acoustic technique for determining depths or creating backscatter imagery in a wide swath of seafloor or lakebed centered below the instrument platform."},{"code":2036,"name":"multibeam sonar","parent":1083,"scope":"Acoustic technique for determining depths or creating backscatter imagery in a wide swath of seafloor or lakebed centered below the instrument platform."},{"code":2038,"name":"sidescan sonar","parent":1083,"scope":"Acoustic technique for creating oblique backscatter imagery of the seafloor or lakebed."}]}