ROCK ISLAND, Ill. — A pair of researchers visited Watch Tower Plaza in Rock Island on Thursday, Jan. 12 as part of a study to determine how the Mississippi River's flow changes over time.
Eric Barefoot, a Geologist with the University of Minnesota Twin Cities and Jimmy Wood, a Master's student, are spearheading the project thanks to a grant given by the National Science Foundation.
"So this surface we're standing on is actually a terrace," Barefoot said. "So it's an elevated surface above the Mississippi River, but this isn't the Mississippi, it's currently several meters below our current location, elevation-wise."
According to Barefoot, the land that Watch Tower Plaza was built on used to be underneath the river around the time of the last ice age.
He and his partner want to know exactly when the Mississippi's water levels started to recede from what is now the Rock Island plaza.
"Rivers are responding to climate change. And they're also responding to all kinds of different factors like sand mining, and a number of other different things like that. And so one of the things that we need to understand about rivers and how they might respond to these future problems that we introduce into our environment is the fundamental processes that govern how rivers behave."
To do that, the researchers augured two 3-inch diameter holes into the ground using a hand drill about two meters deep in order to collect soil samples from different depths.
They'll then send those samples off to a lab and then, using a process called Optically Stimulated Luminescence, they can determine just how long ago that soil was exposed to sunlight and how fast the next layer of soil collected was exposed.
Barefoot says the results of this study can help future scientists and inventors design ways to combat the effect the climate change.
"It may not look like it happens on a day-to-day basis, but [rivers] change over years and decades. And so if we want to design a sustainable future, or we want to build a sustainable landscape and live with the river, we need to understand these processes as we plan for our future."