The Urca de Lima is the only known surviving example of an urca. Although most of a sunken ship's wood is carried away by waves or eaten by shipworms over time, some important elements survive. The Urca's remains include frames, planking, and a ballast pile 100 ft. long and 50 ft. wide. The layer of ballast stones, sand, and sediment cover up and help protect other ship timbers. Five replica concrete cannons replaced the originals that had been removed by treasure hunters, and an iron anchor from another 1715 wreck has been added. An underwater plaque identifies the site and its status as an Underwater Archaeological Preserve.Questions for Diagram 1
1. What is ballast? (Refer to Reading 4 if necessary.) Why do you think ballast piles are so prevalent on Spanish wreck sites today?
2. What happens to most of a sunken ship's wood over time? What can help protect the wood?
3. Study the diagram carefully and then list and describe the components of the wreck site.
4. What information might archaeologists learn from recording, documenting, and studying the remains of the Urca de Lima?
* The image on this screen has a resolution of 72 dots per inch (dpi), and therefore will print poorly. You can obtain a larger version of Diagram 1, but be aware that the file will take as much as 40 seconds to load with a 28.8K modem.