Ultrasound can also be used to: 

i) detect flaws in metal sheets; and

ii) image marine depths. 

iii) searching for metals beneath the earth's surface

 iv) measuring distance v. earthquake detection
 

Ultrasound is used to detect flaws in metal sheets, to image marine depths, and to determine distances. 

The reflected sound waves will not be uniform if the metal sheets have flaws such as cracks or deformity. 

SONAR and RADAR are distance detectors that use the ultrasound principle.