airborne methods  search
NTAVHRR
 AVIRIS
RTaeromagnetic maps
 aircraft
 geophysical methods
 geophysical surveys
 ground methods
 magnetic methods
 multispectral scanner
 photogeology
 remote sensing
 SAR
 SLAR
 thematic mapper
 total-field methods
 vertical-gradient methods
SNBefore 1978, also search airborne.