Island narrowing south of Oregon Inlet (Figure 47) generally 

 occurred as a result of combined ocean and sound shore retreat 

 (Figures 28 and 34). 



Island width changes varied greatly in time in both magnitude 

 and direction (Figure 48). The period 1852-1917 was one of 

 slightly greater island widening; between 1917 and 1980, 

 island narrowing predominated. 



Island axis migration rates (Figure 49) may be positive 

 (seaward-moving) in Back Bay but, because island narrowing 

 along both shorelines predominated here (Figure 47), to con- 

 sider this axis migration as island migration is misleading. 

 It is best thought of as island narrowing, with retreat of the 

 sound shoreline greater than the ocean shoreline. 



Changes directly north and south or Oregon Inlet are the result 

 of inlet processes: the ocean shoreline has retreated and the 

 sound shoreline has prograded (Figures 28 and 34). Processes 

 associated with Oregon Inlet and New Inlet (Figure 9) are 

 responsible. 



Island migration was similar in direction for the 1852-1917 and 

 1917-1980 survey periods, with one exception (Figure 50): the 

 island axis in the region centered on Avon, North Carolina, 

 moved seaward in the former period and toward the mainland in 

 the latter period. This change in direction is primarily the 

 result of a shifting ocean shoreline (Figure 28). 



91 



