By Allison Dahl
From May 7, 2018
Six students and I were lucky enough to start our adventure in the Soufrière Bay collecting sediment samples with Dr. Gregg Brooks and Bekka Larson, geologists from Eckerd College. We learned how to collect core samples using special cylindrical gear that allowed us to examine the layers of sediment. Recently a large sand spill occurred in the area and researchers want to find out where the extra sediment has gone and how it is affecting the nearby reefs. Our four core samples will provide information on the elements and chemicals present in each layer and will give insight to the age of each layer. That afternoon the cores were extruded. Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed through the cylinder until the desired cross-section is exposed, like a push-pop. Two of our sediment samples were extruded 5 millimeters at a time and separated into plastic bags for further analysis. The other two were cut open to see if any visible changes or layers could be seen. With these results and other projects that will be conducted over the next two weeks we will be able to see the impact the city of Soufrière has on its local reefs.
By Cassidy Hinson
From May 7, 2018
Soufrière, the town we are staying in, resides on an island of volcanic origin. It is located in a caldera, a concave volcano that is also named Soufrière, or as the locals call it, Qualibou (‘Place of Death’). This collapse occurred after the volcano had a major eruption. The Pitons, the city, and the water in the bay around it are all part of this caldera. The chain of islands around St. Lucia was formed when the Atlantic plate was subducted under the Caribbean plate, causing land on the border to rise. This geological process continues to this day as the plates continue to converge. The islands started off as underwater volcanoes but continued to build up above ground into the islands we visit today.
Sulfur Springs Park houses a visitor’s information center, a walking tour, and mineral springs. First, we drove to the top of a mountain to the visitor’s center, where we learned about the island’s volcanic past and the original peoples of the island. We then drove to the touring section and our lovely guide Verna showed us around the sulfur springs. The springs spew sulfur into the air giving it a rotten egg smell. The sulfur boils mud and creates steam, with the hottest exit point being well over 350°F. There were French baths that were around 115°F, and a waterfall that led into a small mineral bath. We then went down to the base of the park and headed to the mineral springs, where things got interesting.
The mineral bath was a tub of gray water that felt silty. We had to sit in it for 10 minutes to open our pores. Then, we got out of the bath and headed to the base of a slow-flowing waterfall and slathered grey mud all over ourselves, some more than others. After drying, a local then decorated us with black mud that came from higher up near the volcano’s origin. We then went back into the original pool and tried our best to wash off the minerals, which left our skin feeling really soft. This was definitely a different experience, and one that I had not even dreamt about doing. We learned about the origin of the area that we are calling home for the next two weeks, and gained a new appreciation for this island and the ones around us.
The authors of this blog are students enrolled in Tropical Marine Ecology and Conservation, field courses run in the Caribbean by the University of South Florida. In 2019 and 2021, the course went to the Carmabi research station in Curaçao and dived around the island over a 10-day period, for training and to carry out research projects. In 2018, the group went to Soufriere, Saint Lucia, and took part in various projects in partnership with the Soufriere Marine Management Association. In this blog, students will document their activities and how they relate to course material.