Side-scan Sonar

A side-scan sonar is an acoustic system used to efficiently image large areas of the seabed. This type of equipment, when soundproofing the marine soil acoustically, then measures the intensity of sound reflection.

Hard areas such as rock will reflect the sound more causing a stronger impulse return than less hard areas such as sand or sediment. Objects that rise above the ground form shadows in the sonar image, which correspond to areas not affected by the acoustic impulse and as such do not generate reflection. The size of the shadow can be used to estimate the size of that object.

Figure 1 - Images obtained in an EMEPC survey of the Pegasus and Ville Victoire wreck

It can be used to detect objects or structures on the seabed, for the purpose of search and rescue or directed to underwater archeology. Another purpose is related to the fact that, associating the acoustic survey with the point sampling, it is possible to carry out a mapping of the type of soil and the various textures associated with them. Other applications are related to dredging, studies associated with the environment or military applications such as mine detection.

 

General characteristics of the EMEPC side scan sonar - Sonar Digital 2094:

 

 

 

 

 

 

 

 

This equipment simultaneously acquires data on two different frequencies, 114 and 440 kHz. The system includes the model 159D towable unit, the processing unit and a winch with 1000m of cable.

Brand

Geoacoustics

Model

Sonar 2094 Digital

 

Frequency

114 and 410 kHz simultaneously

 

Prof. Max.

1000m

 

Dimensions

11.4 cm diameter

128.5 cm long

 

Weight

16.3 kg

Comp. Wave

114 kHz - 50º by 1st

410 kHz - 40º by 0.3º

 

Max Reach

114 kHz: 600m

410 kHz: 150m

 

Resolution in the direction of travel

(min)

114 kHz

0.9m with 50m range

1.8m with 100m range

3.5m with 200m range

8.7m with 500m range

 

Resolution in the direction of travel

(max)

410 kHz

0.1m with 20m range

0.3m with 50m range

0.5m with 100m range

0.8m with 150m range

 

Perpendicular resolution

to displacement

114 kHz: 6cm

410 kHz: 2cm

 

 

 

Consult detailed information on technical characteristics click here .