A = scaling parameter dependent on sediment characteristics 

 y = distance offshore 



The findings of this study are complemented by several laboratory studies 

 including Rector (1954); Eagleson, Glenne, and Dracup (1963); Swart 

 (1974); and Vellinga (1983). 



A model concerning shoreline change in response to rising sea level 

 (known as the Bruun Rule) was introduced by Bruun (1962). In this 

 study, Bruun stated that the equilibrium profile described by Equation 1 

 would translate landward and upward while maintaining the original shape 

 of the profile (Figure 2). Additional inner shelf equilibrium profile model 

 studies include Inman and Bagnold (1963), Bailard (1981), and Bowen 

 (1980). These models assume that the oscillatory motion of waves is the 

 most important criterion in the development of the inner shelf equilibrium 

 profile. 



Dean (1977) stated that the equilibrium profile occurs when bed shear 

 stress and the energy flux dissipation rate (function of wave energy den- 

 sity and group velocity) become equal everywhere over the profile. Dean 

 (1983) further defined the equilibrium profile as "an idealization of condi- 

 tions which occur in nature for particular sediment characteristics and 

 steady wave conditions." 



In proposing a model of destructive forces acting in the surf zone that 

 would affect the equilibrium profile, Dean (1977) also reconsidered the 

 equilibrium profile relationship by analyzing 504 beach profiles along the 

 U.S. Atlantic and gulf shores (taken from Hayden et al. (1975)). Dean 

 developed the following relationship: 



w 



k 



MSL t=2 



Wk 







t=1 

 --.^^^^ V, =V2 



Figure 2. Translation of the original equilibrium profile in response to a rising sea level 

 (after Bruun (1962)) 



Chapter 2 Inner Shelf Concepts 



