Sediment Data 
131. The spatial variation of surface sediments along the beach and 
ocean bottom is discussed in this section. Since only two sediment surveys 
were performed during the year, temporal variations could not be defined. 
However, the effect of different wave and current conditions on the sediment 
characteristics (preceding each survey) is discussed. Variations of the sur- 
face sediments onshore were also observed during daily visits to the beach; 
there was a tendency for coarse material during the winter (high wave energy 
season) and fine sand during the calmer wave conditions. 
Shore-normal variation 
132. On 17 March and 26 October, surface sediment samples were taken 
along Profile 188, located 517 m south of the FRF pier. Sediment size was de- 
termined by sieving at 1/4-phi intervals. Figure 44 presents the size distri- 
butions for 17 March as a function of position on the profile. In Figure 45, 
size distributions are shown for some of the sediment samples taken on 
26 October. Consistencies between the samples are observed when the profile 
is divided into the following regimes: (a) dune and beach face, (b) swash 
zone and beach step, (c) nearshore bar and trough, and (d) offshore bar and 
seaward. 
133. Samples taken on the dune generally reflect aeolian (i.e. wind- 
blown) deposition. Therefore, the sediments are well sorted, lacking in both 
very fine sand (due to selective winnowing) and coarse materials. At the toe 
of the dune, however, mean sediment sizes vary from medium to coarse. In 
March, the sediment distribution was moderately well to well sorted using Folk 
(1974) sorting classification. In October, however, wave action placed 
coarser sediments on the dune toe, and fines were winnowed. 
134. Sediments at the beach step were indicative of the high energy 
regime due to waves breaking on the beach. In both March and October, the 
means were coarse (1.9 to 2.4 mm) and the size distributions were moderate to 
poorly sorted. 
135. Seaward of the crest of the nearshore bar, the mean grain size 
generally decreases with distance offshore, and the sediments are better 
sorted. However, after the October storms, the sediments on the inner bar 
(175 m) were coarsely skewed while being finely skewed in March. Figure 46 
shows the effect of the October storms (see paragraph 128 for a description of 
the bathymetry changes). 
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