School of GeoSciences

School of GeoSciences


In the first field season, a range of potential field sites were initially considered. We were looking for sites which contained lagoons of different sizes. We also wanted a range of sites lying on different geology.

Lagoons can be classified into two - open and closed systems. Small lakes with no out flow are classified as closed systems and provide very sensitive indications of localised climate change. Larger water bodies, which are drained by rivers are classed as open systems. These are often less sensitive indicators of change. They are still useful in palaeo-ecological studies such as this one, however, as their large size makes it likely that they will never have dried up during the time period studied.

With the exception of the granitic intrusion that forms the Maya Mountains, the geology of Belize is dominated by limestone. Sites were chosen in both limestone and non-limestone areas to provide a contrast in geochemistry.

The selected fieldsites

Four locations were finally selected for detailed investigation. Their positions are marked on the map of Belize shown to the right.

1. The first site is a small, close d lagoon at Honey Camp (also known as Laguna de On). Recent excavations at this site led by Dr Marilyn Masson (as part of the Belize Postclassic Project) reveal a complex history of settlement.

2. The second site at Lamanai lies on the edge of the New River Lagoon. This is the largest open water body in Belize. Another Maya site, it has a long history of continuous occupation. Excavations at Lamanai have been carried out by Dr David Pendergast and Dr Elizabeth Graham (formerely with the Royal Ontario Museum, now based at University College London).

3. The third site lies in the middle of the Booth's River wetland. The vegetation of this area was studied by a team from Edinburgh in 1996. This is an isolated area in which the remains of many small Maya settlements have been found.

4. The final site is located in the south of Belize at Aguacaliente Swamp, near Laguna village. This site lies on sands and gravels rather than limestone. It gets its name from a hot spring which feeds the lagoon.

Basemap derived from USGS GTOPO30 data. DEM created by Keith Morrison and Ross Purves using their Dynamic Landscapes Java Servlet. Used with permissio n

Map of the sample sites

A series of sediment cores were taken at each site, some at sites at the edge of the lagoon, some in the water. To provide information about the current condition of the lagoon, its water chemistry was measured and collections made of modern algae.

Upper section of the Honey Camp core This image shows the top section of a percussion core taken at the edge of Honey Camp Lagoon. It's dark colour and coarse texture reflects the high organic content of t he material (over 12% by dry weight).
Central section of the Honey Camp core Further down the core, the sediment becomes much finer - dominated by silt and clay-sized particles. A large snail shell can be seen in the left of the core. The fact that this shell is still complete suggests that the sediment was deposited in a low energy environment.
Basal section of the Honey Camp core This final image is from the base of the core. The sediment here is mostly clay. The distinct red and green mottling is indicative of conditions of very limited (or no) oxygen. The se bright colours are caused by the reduction of metal ions such as iron and manganese.

EEO Logo