Today, a small group of us went back to El Lanchon in Puerto Viejo to take measurements of the structure. I finished up photography for the photogrammetry of the top of the barge structure while Wale and Scott ran a baseline along the structure and took measurements of significant features. These included spots of erosion, open hatches, remnants of I-beam and various other small details. Dr. Richards sketched a number of different views of El Lanchon and also took down measurements for some of the smaller features, such as the bitts and cleats.
The ocean was not as calm as it had been last week so we didn’t get a chance to snorkel around or inside of the structure, but the cloudy skies made it an ideal day for taking pictures of the erosion on top of the barge. We also measured each of the 36 major spots of erosion on the deck of the structure. We measured both their width and length and sketched the edge pattern of each section. This process took longer than expected, so we did not manage to complete all that Dr. Richards had planned, but we did finish the plan view of El Lanchon which will support the photogrammetric model.
As the weather began to grow more ominous, we decided to pack up and head back to Cahuita. However, as we were packing, we stumbled across an open hatch that had been overgrown with the weeds and other flora, which is interesting because the rest of the main platform looks like it is, or had been, covered in concrete. We know that there is another hatch that is concreted over somewhere under the flora growth, because during a previous excursion Dr. Richards and Devin came across a ladder that led to it. We took measurements of the hatch opening and used Dr. Richards’ dive knife to probe around the hole to see where the concrete ended and the dirt began. The concrete stops much farther back than we had previously thought. We assumed that the dirt where the flora was contained had been placed on the concrete layer, but instead it appears that the dirt was placed directly on the iron of the original structure. We’re still not sure if concrete was a part of the original structure or a later addition, but the information we gathered while investing the hidden open hatch may help to answer that question.
-Sydney