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Monday, November 8, 2004
Dave Conlin studied
anthropology and archeology as an undergraduate at Reed College in
Portland Oregon and continued his graduate studies in archeology at
Oxford University in England and at Brown University in Providence, Rhode
Island. He was the field director for the recovery of the Confederate submarine
H. L. Hunley in 2000, the
Ellis Island Ferry in 2002 and the
Lake Mead B-29 in 2002 and 2003. |
Day of Density
Yesterday evening at
the end of our day off we bid farewell to our new favorite materials
engineer, Sheryl Johnson. Sheryl had generously decided to spend some
vacation time to see what her uncle. Dr. Don Johnson, has been doing
these past five years and to bring some of her analytical skills to bear
on the science the team is doing on the wreck. Sheryl, a materials and
testing engineer at Seagate Technologies in Boulder Colorado, took all
day on Saturday to assist Don with density calculations on the
concretion.
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Dr. Don and Sheryl Johnson analyze the
concretion samples in our makeshift lab. Photo by Brett Seymour,
NPS. |
Today, not
completely sure about the completeness of the data, Don and Matt Russell
re-ran density calculations for the samples of concretion we had
recovered with our hole saw prior to ultrasonic thickness testing. The
concretion, a layer of living and dead marine organisms cemented with
corrosion product, may offer an indirect and minimally invasive method
of determining the amount of corrosion that has taken place at a
particular location on
Arizona. One of the reasons we're collecting density data for the concretion is
to see if we can correlate it with either the measured thickness of the
hull as determined by the UT probe, with the Ecorr
measurements, or with both. If we can determine this, we can maybe say
how much metal remains - this is crucial data for refining the finite
element model and getting an accurate idea of how the wreck is holding
up.
At noon, the
Arizona project lost the second half of its brain trust as Don and
his wife Dorothy left the project to head back to Sun City West. Matt
spent the remainder of the afternoon working with the SonTek wave and
current meter, downloading environmental data for the waves and currents
that affect the wreck. Art Ireland, our one-man logistics empire,
helped Don and Matt, ran tanks, made an airport run and still had some
time for a few salty comments about the quality of Dave Conlin's and
Brett's photo frame.
Dave and Brett spent the day putting
together an AMAZING machine from PVC pipe, a section of fiberglass
angle, some mooring balls and a very expensive underwater housing for
the project digital camera. The photo frame will hold our digital
camera a fixed height off the deck of the wreck and allow us to make a
detailed photomosaic (a composite image from many smaller images) of the
bow of Arizona. With lights from Hydroflex Inc. we should be
able to control the contrast and exposure. We'll manipulate the image
with Photoshop to get something we can use both as a management and
interpretive tool. And so far we've only had to go to Home Depot three
times. . . .
Art Ireland (standing) supervises as Brett Seymour and Dave Conlin
engineer the photomosaic frame for this
week's operation. Photo by Matt Russell, NPS.
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