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Surface and Subsurface Morphology of the Beach Ridge Plain
A summary of the characteristics of each beach ridge set, including average ridge crest
elevation, average swale elevation, ridge orientation, direction of ridge splay and width of each
beach ridge set at its widest point, is shown in Table 4.2.
Topographic Survey Results
A leveling profile was conducted along a north-south transect across the island, following
Road 4. This line crossed the trend of most of the beach ridge sets. The goal of the survey was
to accurately measure the elevations of individual beach ridge crests and swales and the mean
elevation of ridge sets. The location of the topographic survey line conducted across St. Vincent
Island is shown in Figure 4.23. As discussed in Chapter 3, a benchmark was set at each sample
location. The elevations of these benchmarks were measured as part of the topographic survey.
Figure 4.24 shows the result of the topographic survey. Table 4.3 shows the measured elevations
of each benchmark. The blue line represents the survey conducted by Stapor as part of his
dissertation work in 1973. The red line represents the survey conducted Stapor and Tanner
(1977). The red line represents the survey conducted during this investigation. The two
independent surveys are in reasonably good agreement. The green line represents the elevation
of the road, which was also determined as part of this investigation. Since the road cuts through
the high ridges, it mutes the natural topography. The boundaries between the ridge sets
intersected by this transect have been superimposed on Figure 4.24, in addition to the locations
of all samples that were collected along Road 4.
Several features are apparent in Figure 4.24:
1) The profile obtained during this study closely agrees with the profile obtained by
Stapor and Tanner (1977). However, one beach ridge within set K has been eroded in
the time elapsed between the current study and the Stapor and Tanner (1977) study.
2) Set K has one ridge with an elevation of 3.8 m.
3) The average elevation of the ridges in ridge set G is 2.4 m. Within this set there are
two high ridges (containing sample sites SVI 009 and SVI 023) with elevations of 4.4
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