out from the latest beach, converting the latter into a marsh bar, or "chenier. " 

 The cause of variations in supply of sediment was shifting of positions of the 

 Lower Mississippi River outlets, along the coast to the east. Here, as in 

 several other parts of the world, a "chenier plain" has developed, in which 

 more or less parallel strips of marsh alternate with tree -covered, higher 

 strips of abandoned beach. 



DISCUSSION 



Redfield: I would like to call your attention to the marshes which were 



just discussed (marshes occurring behind beach ridges). I 

 think this afternoon we are going across the island to the out- 

 er beach. You will be impressed there, I think, by the fact 

 that there are several ridges perhaps analagous to this form- 

 ation with marshes in between. When we go to Blackbeard 

 Island I think you will see a series of beach ridges in parallel 

 with no marshes between them; they are too high. 



31 



