- 天同Lv 71 decade agoFavorite Answer
Ultrasonic waves are used due to their short wavelength. Since the frequency of ultrasound is very high, the ultrasound waves can be sent out in the form of a beam. It is thus possible to radiate out a large amount of energy to a distance point at the ocean bottom.
If ordinary sound waves are used, the sound waves would spread out. Because of the absorption of wave energy by the sea water, the waves weaken rapidly. The reflected waves from the bed of the ocean would become too weak to detect.
- 1 decade ago