Table 9 

 1980 Aerial Photography Inventory 



Dale 



Flight Line No. 1 



Flight Line No. 2 



Flight Line No. 3 



(Negatives) 

 Film Format 



16 Jan 



2 miles north to 2 miles 

 south (1:6,000) 



Color 







2 miles north to 2 miles 

 south (1:2,400) 





Color 



16 Jan 



Cape Henry to Cape 

 Hatteras (1:12,000) 



+2 miles north to the 

 pier (1:6,000) 



Currituck Sound to 

 Atlantic Ocean 

 (1:12,000) 



B/W 



15 Apr 





2 miles north to 2 miles 

 south (1:6,000) 



2 miles north to 2 miles 

 south (1:2,400) 





Color 

 Color 



15 Jul 



Corolla to Oregon 

 Inlet (1:12,000) 



2 miles north to 2 miles 

 south (1:6,000) 



Currituck Sound to 

 Atlantic Ocean 

 (1:12,000) 



B/W 



15 Oct 



Corolla to Kitty 

 Hawk (1:6,000) 







B/W 



from the seaward end of the pier to the 33-ni water depth. 



142. Between 4 January and 30 December, 130 surface sand samples were 

 taken from the upper swash zone of the foreshore, 500 m updrift from the pier. 

 Weekly samples were taken from January through June and during December, while 

 daily samples were taken from July through November. Table 10 presents sta- 

 tistical parameters of the sediment distribution for each sample, and Fig- 

 ure 35 shows the mean grain size as determined from CERC's Rapid Sediment 

 Analyzer (RSA) analysis. Considerable scatter is evident, but a trend for 

 smaller sizes during the relatively low wave conditions during July and larger 

 sizes in December and January (times of high wave conditions) can be seen. 

 Caution should be exercised when using the mean of a sample to infer typical 

 grain sizes found on the beach. Frequently, the mean may not be a true indi- 

 cator of a predominant size found in the sample, but simply an average based 

 on the distribution of sizes. This is particularly true as the sizes become 

 more coarse, since the analysis reports frequencies at 1/2-phi intervals and 

 increasingly larger intervals of sizes occur between classification limits as 

 shown in the tabulation on page 77. 



143. As an example, a sample taken on 20 November 1980 is described on 

 page 78. The frequency distribution, given in the tabulation, shows a 



73 



