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We spent half the day bringing the seismic equipment aboard the US Army Corps of Engineers
M/V Strong. Once aboard and secure, we left the Ensley shipyard near President’s Island in
southeast Shelby County toward Memphis. We were to start in Helena, but we wanted
to deploy the equipment into the Mississippi River to run tests. It would be better
to be close to Memphis in case we needed some parts or needed to build some equipment
infrastructure.
The equipment tests worked out fine except for the Chirp, a high-frequency seismic
source emitter that would enable us to see high detail at shallow depths (<50 ft.).
The other seismic source consisted of an energy source and hydrophones (listening
devices), both suspended in the water with a buoy. This equipment would allow us
to see stratigraphic changes and faulting to depths of nearly 0.5 miles beneath the
river bottom. Naming the project “Huck Finn” after Mark Twain’s classic tale of
adventure on the Mississippi River, we named the hydrophone buoy Huck and the seismic
source buoy Jim. This naming had an important purpose because we watch Huck and Jim
very closely to make sure all was well with the equipment.
As it turned out, we did need to modify the deployment equipment for Jim. The equipment
was extremely heavy and we needed a way to hoist the equipment back onto the boat
each day. A winch was used to send out and bring in the source to the M/V Strong,
but it was below deck level. Thankfully the Corps had a welder on board. We developed
a block cable system that would cantilever from an overhead steel I-beam. This was
welded in place and we were set.
Shortly after our testing and modifications, we headed south toward Helena, AR where
we would begin our long, 200 mile journey up river to Caruthersville, MO. Needless
to say, the Mississippi River gave everyone an idea of why it is called the “Mighty
Mississippi”…and not just because it’s the fifth largest river in the world.
We hit a storm. A really big storm. With winds topping 70 mph, swells formed in
the river between 3-4 feet. Safe on the M/V Strong and with the Corps crew looking
after us, we made it through the storm unscathed and the equipment intact.
We arrived safely at Helena.
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