Monday, July 5, 2010

Week 7: June 28 - July 2: By Rebecca Booker and Hallie Johnson

June 28-30, 2010
By: Rebecca Booker

After a rainy weekend Monday was no better. However we did take advantage of the situation in order to learn some very good skills.  The morning started out with a lecture by Greg Cook. He talked about the three different types of remote sensing that is used in maritime archaeology: side scan sonar, magnetometer, and sub-bottom profiler.  In the afternoon we headed back to MSC and we all took a class in O2 certification.

On Tuesday it was another rain day. We headed to Baptist hospital to look at their recompression chambers. There were a lot of interesting stories told about what the chamber has been used for and all the different type of chambers that are out there. After a quick lunch it was off to campus to hear lectures from both Jake Shidner and Sarah Linden.

Wednesday! The first day back in the water since the oil hit last Thursday. We traveled to the Blackwater River. There were two dive teams and one survey team in the Shield's Point area.  The two dive teams dove on three known ships-the Dinty Moore, the Geo. (George) T. Locke, and the Guana Cast. The survey team used side scan sonar to look for any other ships in the general area.  At the end of the day one of the boats had to be towed back to the dock. This gave us a good chance to practice our knots.

(A friendly tow from one of the other field school boat.)

July 1-2, 2010
By: Hallie Johnson

Thursday: Today we looked at the results of Wednesday's side scan sonar survey at Shield's Point in the Blackwater River, as well as the data from a previous survey off Dead Man's Island. Greg Cook gave a lecture on what constitutes a real hit from the sonar and other things in the water, like schools of fish and boat wakes that can create noise in the image. A hard return, which is normally the bright area, with a shadow means there is a definite object. While looking at the data we identified anomalies that might be potential sites to dive on. We were also able to see the side scan images of wreck 6 at Shield's Point and what might possibly be a new wreck. The data from Dead Man's Island was very different form Shield's point because the water was much rougher, which created a different kind of noise than the relatively calm waters at Shield's Point.

(Debrief at the end of the day after our dive operations.)
Friday: The weather held out for us today and we were able to get boats out on the water. We returned to the Blackwater River, diving on some of the potentials from yesterday's lab work. The circle searches did not yield any new wrecks, but there are more targets for further research. Today we also dove on some known wrecks in the area, documenting how much of the vessels were exposed, measuring the dimension of the wrecks and mapping out interesting components of the vessels. The visibility at Shield's Point made this a little difficult, but we were still able get good information.

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(Field school student Capri Wright and Graduate Supervisor Aleks Adams after a dive in the Blackwater River.)

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