Friday, June 8, 2012

Cape Henlopen Shipwreck X -by Danielle Ferraro

On June 4th, 2012, a survey team conducted a side-scan sonar and ROV investigation of an unknown shipwreck off Cape Henlopen in Lewes, Delaware. The team consisted of CHSEL lab director Dr. Art Trembanis, ROV surveyor Jeff Snyder, state archeologist Craig Lukezic, graduate students Trevor Metz and Carter DuVal, and undergraduate intern Danielle Ferraro. This was the first time the wreck had been investigated in depth since its discovery in 2010. 

Using an EdgeTech 4125 600/1600 side-scan sonar, we were able to make several passes over the shipwreck site. Amazingly, the wreck was only 175 meters from the Lewes shoreline and five meters submerged. While it seems unlikely that the wreck had not been previously detected, it may have been covered in sediment and eventually exposed by strong wind-driven currents during a relatively recent storm.


Once we captured strong sonar data of the wreck, our research vessel was anchored and the VideoRay ROV was prepared for deployment. (Watch the deployment of the ROV here.) The ROV had a BlueView 900 130° multibeam bathymetry sonar as well as a video capture. The BlueView sonar enabled Jeff to establish a proper heading and provided us with a better look at the entirety of the wreck. It seemed that the ship had suffered damage in the presumed bow section. On the presumed stern side, some ribbing, a mast beam, and possibly a hatch may have still been intact, though no definite identification of features have been made thus far through the multibeam returns. The video taken by the ROV was streamed onto a topside computer for real time viewing. Much of the wreck was encrusted with mussels, and other invertebrates such as anemones colonized some sides. 


As the day progressed, the winds increased and caused the currents to pick up. It was increasingly difficult to control the ROV's movements in the turbulent shallow water. Despite this, much was learned about this unknown shipwreck. It seems likely that the ship was steel or iron, due to the hard sonar returns and large amount of wreck that was still structurally intact. Given the amount of time the ship was submerged based on the magnitude of invertebrate colonization, a wooden ship would have mostly deteriorated by this point. We will investigate further to try to identify the wreck by comparing our findings to state and local records. Stay tuned!

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