MULTIPLE REFLECTED WAVES 



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from thin layers (*). It is also found that in the case of reflection from a thin 

 layer the damping of multiple waves with distance decreases as the difference 

 between the wave resistance in the reflecting layer and the wave resistance 

 in the underlying medium increases. 



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£ 30 



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c. arad 



Fig. 10b. 



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The damping of reflected waves with distance from the source is in inverse 

 ratio to the number of multiples. Fig. 11 shows the results obtained from 

 modelling in the case of a thin reflecting layer. It can be seen that at short 

 distances from the source and when the reflecting boundary is at shallow 

 depths, the intensity of the multiple waves diminishes as the number of 

 multiples increases. Further away from the source double waves become more 

 intensive than single ones (Fig. 4). Still further away, triples are more intensive 



