ground-penetrating radar  search
BTradar methods
 .ground-penetrating radar
UFground penetrating radar
 ground probing radar
RTgeophysical surveys
 reflection methods
 ground methods
 high-resolution methods
 radio-wave methods
 microwave methods
SNTime-domain impulse radar which transmits broad bandwidth pulses into geologic media and acts as a sounding device. Before 1993, also search radar methods and ground methods, GPR. For surveys, also index geophysical surveys. Added to Thesaurus in 1993.