120 Lecture 6 
Niveaux sonores 
(1 db par carreau) 
HHH 
+ 
26y=5 =4" =3) =2) = 1 Oma 2 EN SY PON? 
1 
(0.5 m) (Im) Distance en db: re: 1m xe) 
clest a dire 20 log (rmatres) 
Fig. 6.18. Acoustic field at different frequencies. 
6.4.2. General Description 
The artificial lake of Castillon was created by a dam erected across the 
valley of the Gorges de Verdon, 6 kmto the north of Castellane and at a distance 
of 146 km by road from Toulon. 
The lake depth varies with the seasons, attaining a maximum of 80 m during 
December and January and again during June and July, while the lowest depth 
of 40 m occurs in April and September. The crest of the dam has a height of 
85 m. 
The test-and-calibration barge is moored in the middle of the lake nearly 
400 m from the dam in an area measuring 200 by 400 m and corresponding to 
the lowest bottom level. 
