studies were concerned with the restoration potential of the Terrebonne Parish 

 barrier islands. At the present time several of these proposed projects are 

 being initiated (Meyer-Arendt and Wicker 1982). 



20. Models for the development of barrier islands have been proposed by 

 Hoyt (1967, 1970), Fisher (1968), and Otvos (1970). Using characteristics of 

 the barriers of the Atlantic as typified by those of the Georgia coast, Hoyt 

 (1967) proposed that barrier islands are initiated when wind or water- 

 deposited sediments are built into a ridge immediately landward of the shore- 

 line. Slow submergence, as during the late Holocene, floods the area behind 

 the ridge producing the barrier island (Hoyt 1970). 



21. Fisher (1968) proposes that barrier islands form as complex chains 

 of spits on a shoreline of submergence. This hypothesis has some merit be- 

 cause we see spit growth occurring today, but it probably is not the major 

 cause of barrier island development. Otvos (1970) proposed that barrier is- 

 lands form by the upward aggradation of submerged shoals. Recent studies by 

 Schwartz (1973) and Swift (1975) have also focused on barrier island origin 

 and development, but these works have generally reiterated the earlier views 

 presented by Hoyt, Fisher, and Otvos. Field and Duane (1976) have presented 

 an alternative model for the origin of barrier islands. They propose that a 

 barrier coast is one that alternately erodes and progrades, but ultimately re- 

 treats in concert with a fluctuating (but steadily rising) Holocene sea. The 

 shape and nature of both the surface and subsurface deposits of the inner 

 shelf, orientation of shelf features, and association of continental shelf 

 shoals with capes, inlets, and barrier spits on the east coast support the ob- 

 servation that barriers may originate on the shelf and retreat landward. The 

 controversy over the origin of barrier islands remains largely unresolved, be- 

 cause most of the evidence pertaining to their origin has usually been de- 

 stroyed by subsequent reworking. Most authors generally agree that barrier 

 islands can be formed by several processes. 



22. Isles Dernieres have been called barrier islands by previous au- 

 thors, but it should be understood that the use of the term "barrier island" 

 does not imply an origin similar to that of barrier islands found along other 

 coasts. Although the processes controlling the migration of Isles Dernieres 

 are similar to those proposed as causes for the origin of other barrier is- 

 lands, these processes cannot be used to explain the origin of Isles Dernieres. 

 The origin of Isles Dernieres has been best described by an evolutionary model 



14 



