18
down the components of a device designed to recover long tubes of sediment (sand,
mud, etc.) from beneath the surface of the island. This is our vibracoring system.
Long aluminum tubes, some with discs on the bottom, and a platform on the top
(Fig. 2.2) are handed down. Others start pulling items from the back of the van –
tools and an engine with a long cable attached. Another student, who is using the
data for a thesis, consults with the professor (that would be me) on our location and
the anticipated geology. We record our position with a global positioning system
(GPS) unit and look at some geophysical data that show the layering beneath the
ground here where we stand, the results of a ground penetrating radar (GPR) survey
done earlier in the season. The GPR device shoots radio waves into the ground,
which are reflected back where changes occur in the sediments below the ground.
The reflection is recorded and reveals the layers and buried secrets of the island,
showing us what existed before today; inlets, beaches, marshes, dunes, etc.
We break out various wrenches and other tools and begin the construction of a
vibracore tripod on the sand flat, with which we intend to recover the layers and
expose the buried secrets. It’s another day in the office for these coastal geologists.
At 5 pm, everyone is tired, having been at it since 7 am, when the temperatures were
more inviting. But the challenge, if only for bragging rights, is to get the most and/
or the longest cores in a day. The students are up to the challenge.
The core pipe is lifted with the vibrating head clamped near the top (Fig. 2.3).
The engine is started and the vibrator roars to life in an ear-piercing rattle. The core
pipe rapidly sinks through the sand at first, then slows. Tourists driving by slow
down and point, as if we’re another novel variety of wildlife on these islands. We
wave and smile when we can. The geologists twist the vibrator and pipe, trying to
force the pipe to penetrate deeper into the island sands. The objective is to recover
sediments – sand, mud, shells, organic material, that occur beneath the surface and
record the history of this island.
Why do we expend our blood, sweat, and tears to recover a pipe full of sand? It’s
all about the lure of adventure and knowledge; the knowledge being critical to
Fig. 2.2 Photograph of
students unloading the
tripod for the vibracore on
the Outer Banks, NC
(Hatteras Island). (Image
by S.J. Culver)
D. J. Mallinson
down the components of a device designed to recover long tubes of sediment (sand,
mud, etc.) from beneath the surface of the island. This is our vibracoring system.
Long aluminum tubes, some with discs on the bottom, and a platform on the top
(Fig. 2.2) are handed down. Others start pulling items from the back of the van –
tools and an engine with a long cable attached. Another student, who is using the
data for a thesis, consults with the professor (that would be me) on our location and
the anticipated geology. We record our position with a global positioning system
(GPS) unit and look at some geophysical data that show the layering beneath the
ground here where we stand, the results of a ground penetrating radar (GPR) survey
done earlier in the season. The GPR device shoots radio waves into the ground,
which are reflected back where changes occur in the sediments below the ground.
The reflection is recorded and reveals the layers and buried secrets of the island,
showing us what existed before today; inlets, beaches, marshes, dunes, etc.
We break out various wrenches and other tools and begin the construction of a
vibracore tripod on the sand flat, with which we intend to recover the layers and
expose the buried secrets. It’s another day in the office for these coastal geologists.
At 5 pm, everyone is tired, having been at it since 7 am, when the temperatures were
more inviting. But the challenge, if only for bragging rights, is to get the most and/
or the longest cores in a day. The students are up to the challenge.
The core pipe is lifted with the vibrating head clamped near the top (Fig. 2.3).
The engine is started and the vibrator roars to life in an ear-piercing rattle. The core
pipe rapidly sinks through the sand at first, then slows. Tourists driving by slow
down and point, as if we’re another novel variety of wildlife on these islands. We
wave and smile when we can. The geologists twist the vibrator and pipe, trying to
force the pipe to penetrate deeper into the island sands. The objective is to recover
sediments – sand, mud, shells, organic material, that occur beneath the surface and
record the history of this island.
Why do we expend our blood, sweat, and tears to recover a pipe full of sand? It’s
all about the lure of adventure and knowledge; the knowledge being critical to
Fig. 2.2 Photograph of
students unloading the
tripod for the vibracore on
the Outer Banks, NC
(Hatteras Island). (Image
by S.J. Culver)
D. J. Mallinson