Ambergris Caye Belize Resort Development - Department of ...

2.5.3 Geomorphology
The beaches of the project site are linear with no discernible embayments. This configuration is
consistent with the orientation of the crest of the barrier reef which lies 0.8 miles from the
beach.
The sand grains are angular and moderate in size. The sand is biogeneic in origin and are
derived from the bio-erosional processes of corals shells, calcareous algae, and other
calcareous materials.
The beach is approximately 1 m in elevation and is gently sloping with a vegetated berm that is
about 1.5m in height, as measured from the low tide line. The property is defined by a number
of ridges running parallel with the beach and which begins about 100 m from the beach: These
are in effect relic beach berms that are a function of the rise and fall of sea level over geologic
time-frames.
The leeward side of the property is characterized by lowland mangrove which merges with the
Laguna de Cantena.
2.5.3 Local Area Geology
The depositional processes of the area are wholly influenced by marine processes. The net
long-shore drift along the beach is from north to south, which is co-incident with the net
current flow in the area.
The major beach sediments were Halimeda sand.
The topography of the development site is generally flat, punctuated intermittently by the relic
beach berms cited earlier. The caye slopes gently upwards to about 3/5 th the distance from the
sea to the lagoon [See Figs. 2.5A & 2.5B]. After the highest point of the project site is reached,
the elevation then gently falls until it reaches the low-land mangroves [See Fig. 2.5A & 2.5B].
The surficial sediments consists of a thin layers of humus interspersed with sand followed by a
pure layer of sand. The layer of humus is especially apparent in the midreaches of the littoral
forest and on the leeward side of the caye leading to the approaches of the lowland mangroves.
The mid 2/5 th portion of the caye is characterized by a fair amount of small to medium sized
rocks, which are probably intermittently deposited by catastrophic storm events [Pers. comm..,
G. Myvett].
The major component of unconsolidated sediments is fairly fine-grained calcareous sand. The
depth of unconsolidated sediments, relative to the bedrock layer, varies from 3 to 7 meters [See
Fig. 2.5]. The thickest layers occur at the highest elevation, with the thinnest layers being at the
beach on the windward side, and at the shores of the lagoon on the leeward side [See Fig. 2.5].
The bedrock was consolidated limestone [See Fig. 2.5].
The Water Table varied from 0.5 to 4.5 meters [See Figs. 2.5]
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