SONAR SURVEY

SN Active sonar systems are based on the behaviour of sound waves in water; acoustic energy is transmitted and the time for the returning echo is measured to allow submerged seabed features to be mapped. Use specific type where known.
CL NON INTRUSIVE EVENT
BT GEOPHYSICAL SURVEY
NT BATHYMETRIC SURVEY
MULTI BEAM ECHO SOUNDER SURVEY
SIDE SCAN SONAR SURVEY
SINGLE BEAM ECHO SOUNDER SURVEY
SUB BOTTOM PROFILING SURVEY