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Sample Sites
CHAPTER 4
RESULTS
A total of twenty-nine sites were investigated on St. Vincent Island. Of these twenty-nine
sites, eight were dated using Optically Stimulated Luminescence (OSL). Figure 4.1 shows the
location of the samples collected over the course of this investigation and indicates which were
vibracores and which were trenches. Each sampling site is briefly described below. Note: All
coordinates are UTM Zone 16 (NAD 83). Table 4.1 lists all sample site numbers and sample
locations.
Beach ridge type is related to environmental conditions. The identification of beach ridge
type is, therefore, important. Taylor and Stone (1996) and Tanner (1995) discuss the multiple
origins of beach ridges, noting that morphology alone does not distinguish swash-built ridges
from aeolian or storm-deposited ridges. However, internal structure is diagnostic. Beach ridge
internal structure is difficult to observe and measure. This problem is in large part solved by the
excavation of trenches. In this investigation, trenches enabled direct observation of the basal
deposits of former shoreline ridges, and, therefore, enabled sampling of only the wave-deposited
portions of complex beach ridges that include aeolian deposition on their surface. In the ridges
trenched, those that have visible bedding surfaces reveal a wave-built structure, with some
aeolian decoration and no evidence of storm influence (i.e., the ridges exhibit seaward-dipping
units throughout the ridge strata). This supports the swash-built hypothesis for beach ridge
formation, proposed by Stapor (1973, 1975), Stapor et al. (1991) and Tanner (1995), and serves
as good evidence that each ridge represents a former shoreline position. By collecting samples
from the exposed walls of trenches it was also possible to avoid collecting samples from areas
that had been affected by bioturbation. An example of a typical trench is shown in Figure 4.2. A
total of 18 trenches were excavated. Sample sites are described below. All information relevant
to each site is presented in Table 4.1.
SVI 001
This site, located within ridge set A, is referred to as the “Paradise Point Site”. It is the
location of the complex midden site described in chapter 3. This site was first visited on July 23,
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