176. Figure 59 shows percentage of segments with orientations in speci- 

 fied degree categories. Shorelines in 64 percent of the segments are aligned 

 in a general northeast- southwest direction between 30 and 90 deg. 



177. Scatter plots showing shoreline orientation versus average annual 

 and maximum shoreline change for all segments were completed (Figure 60) . 

 These did not show a significant trend that might indicate a direct relation- 

 ship between shoreline orientation and shoreline movement. Separate plots 

 were made for each of the seven coastal reaches to see if trends occurred in 

 certain geomorphic areas. None of the reach plots indicated the existence of 

 significant correlation. Figure 61 showing data spread for reach 2 is 

 typical. 



178. Absence of trends indicating a relationship between shoreline 

 movement and shoreline orientation suggests that orientation to approaching 

 waves by itself does not have a substantial effect on shoreline changes. The 

 previous section indicated that orientation was a significant factor in recep- 

 tion of large period waves; however, no correlation was evident between wave 

 period and shoreline change. None the less, the east-west arcuate strand, 

 which has fewest T > 11 sec waves, has the most stable coastline, and north- 

 south oriented reaches 1, 2, and the segment of reach 7 north of Cape Fear 

 have widespread erosion. 



Bathymetry 



179. Nearshore bottom slopes and historical shoreline changes were com- 

 pared to determine if there was any correlation. For this purpose, distance 

 from the shoreline midpoint of each coastal segment to the 1.8-m, 5.5-m, and 

 9.1-m depth contours was measured on 1:80,000 scale NOS hydrographic charts. 

 Corresponding slopes were calculated. Average yearly shoreline change and 

 maximum shoreline change were compared with slope for each coastal segment. 



180. Scatter plots of nearshore slope angles versus average and maximum 

 shoreline changes in each segment were constructed (e.g. Figure 62). In gen- 

 eral, the scatter plots show that there is little apparent correlation between 

 nearshore slopes and either maximum or average annual shoreline change. To 

 further examine the data, scatter plots were made for each of the seven 

 reaches. However, there appeared to be little correlation between nearshore 

 slopes and shoreline change in any individual reaches. 



181. Figure 63 showing data for reach 6 indicates increasing shoreline 

 movement with gentler slopes; however, there are too few data points at 



129 



