Collaboration
Between USC’s Department of Geological Sciences and the Maritime Research
Division
By Christopher Amer and
Jeffery Morin
I was nestled tightly between a
coring frame and a life raft two decks above the roiling sea pondering the
meaning of life when the wave hit drenching me out of my existential reverie (Figures
1a an 1b). The ship Jeff Morin, of USC’s Department of Geological Sciences,
and I were on was the 185-foot research vessel Endeavor, a National
Science Foundation vessel operated by the University of Rhode Island (Figure 2).
The occasion was the return trip to Charleston around Frying Pan Shoal off Cape
Fear where myself along with MRD staffers Lora Holland, Carl Naylor, and Jim
Spirek had recovered three underwater instruments, nicknamed “Bigfoot 1 and 2”
and “Mini-me.” The project was part of an ongoing collaboration between
SCIAA’s MRD and USC’s Department of Geology that has spanned some five years.
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In
December of 2002, USC’S Department of Geological Sciences and SCIAA
signed an
Agreement of Cooperation designed to enable the two groups to assist
each other
on applied marine research projects that would be mutually beneficial
to the
university, research, and scholarship in general. The collaboration
makes
perfect sense as many of our research interests overlap and much of our
equipment can be shared. For example, a shipwreck site in the context
of a
barrier island may become alternately buried and exposed as the shore
accretes
and erodes due to natural physical forces like waves, currents and
storms.
Understanding the causes and effects of these forces can greatly aid
archaeologists in investigating and interpreting shipwreck sites, as
well as
planning strategies for long-term management of the sites. Already,
partnerships
with geologists and sedimentologists from both USC and Coastal Carolina
University have helped archaeologists interpret the post depositional
history of the H.
L. Hunley site, prioritize areas to survey for the remains of Lucas Vazquez
de Ayllon’s lost Capitana, and survey for Confederate cannons in the waters of
Charleston Harbor (Figure 3).
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This cooperation
between
SCIAA’s MRD and USC's Department of Geological Sciences is having a
much
broader impact on the coastal regions of the state and the nation.
Erosion of
the coastlines of the continental United States is a serious national
problem
that poses a significant threat to human lives, property, and the
environment.
Locally, this is felt acutely in the rapidly developing coastal regions
of South Carolina, which are plagued by severe ongoing erosion.
The
Coastal Processes and Sediment Dynamics Lab (CPSD) at USC, under the direction
of Dr. George Voulgaris, is currently involved in a number of investigations
designed to determine the physical forces (e.g. waves, currents) influencing
the transport of sediment in coastal environments through continuous data
collection at sites along the South Carolina and North Carolina coasts. These
projects include the South Carolina Coastal Erosion Study (SCCES) supported by
the United States Geological Survey (USGS, Department of the Interior),
monitoring associated with the South East U.S. Coastal Ocean Observing System
(SEACOOS) funded through the Office of Naval Research (ONR), and a National
Science Foundation (NSF) study designed to describe the movement of sediments
on the North Carolina shelf and how this transport defines the shape and
structure of the bed forms observed. One way of visualizing sediment transport
in coastal areas is through placement of instruments designed to measure concentration
and particle velocity in the path of transfer. These instruments include a wide
variety of acoustic devices deployed autonomously on observation platforms
(SCCES, and the North Carolina bedform study) and current measuring acoustic
systems connected to pier communication systems supplying real time
measurements of wave features and current profile characteristics (SEACOOS).
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The
research projects require placement of instrumentation underwater in
the
regions of interest. To accomplish the goals of the projects, staff of
SCIAA’s
MRD perform multiple invaluable tasks insuring proper placement of
observation
platforms and continuous measurement systems. The coastal erosion and
North Carolina bedform projects involve placement of sonar imaging and
particle measuring
instruments on observation tripods in specific types of sediment
(Figure 4).
The divers assist in these efforts by conducting pre-deployment surveys
of the
intended sites, establishing the exact positions where the platforms
will be
placed for periods of months. When the platforms are recovered MRD
staff enters
the waters where the platforms are collecting data to locate them. A
signaling
device assists in the location of the platform by sending an acoustic
ping to a
diver operated receiver. Once the platforms are located the divers use
recovery lines to attach the platforms to large inflatable buoys on the
surface
of the water
(Figure 5).
The continuous
monitoring
associated with the SEACOOS program requires placement of acoustic
Doppler
current profilers (ADCPs) in the vicinity of recreational piers on the
coast of South Carolina (Figure 6). These ADCPs are housed in large
anti-trawl
devices manually lowered to the seafloor through diver assistance
(Figure 7).
They are attached to computers on the pier, via cabling running on the
seafloor, where wave and current data is sent to the CPSD lab in
Columbia to be processed, archived, and posted on various web sites.
Maintenance of the
monitoring systems involves locating the ADCPs, disconnecting them and
raising
them to the surface for replacement. MRD staff rapidly locates and
recovers
the acoustic systems so that they can be maintained to insure
continuous data
collection. Data from the two ADCP units located off Springmaid and
Folly
piers can be accessed at
http://www.geol.sc.edu/gvoulgar/waves.html.
Collaboration is the bedrock upon
which successful research is built. While the coast of our state may be as
unstable as the pluff mud in its marshes and the sand of its barrier islands
the collaborative research of these two USC groups sits upon solid firmament.
