"Cartersville is actually one of the toughest areas in the Southeast I think to do geologic mapping," said Julian Gray, curator for Tellus, a 120,000 square feet Cartersville museum that is comprised of four main galleries -- The Weinman Mineral Gallery, The Fossil Gallery, Science in Motion and The Collins Family My Big Backyard -- a 120-seat digital planetarium and an observatory equipped with a 20-inch telescope. "This is an area where three physiographic provinces come together. We've got the Valley and Ridge to the Northwest, the Piedmont and the Blue Ridge all come together in the Cartersville/Emerson area and it makes it very interesting for geologists.
"There's actually a team of three or four geologists that have been working on these maps for decades and this is the culmination of really their life's work in this area. It's the current state of scientific thinking. It's the highest scientific thinking about geology in this area," Gray said.
Along with revealing an area's rock placement, Gray said the vibrant maps also show if a rock layer is parallel to or "plunging" into the ground.
"What geologic maps are in general is it shows the distribution of the different rocks, just like a road map shows the roads, and we colorize the geologies," said Randy Kath, professor of geology at the University of West Georgia. "For instance, the unit over there that's mined so much in the Cartersville district is a blue color so everywhere on the map you see a blue color that's where the Shady dolomite is.
"So really it shows the surface geology in plan view and then we make cross sections where it's kind of like cutting a slice into the Earth so we can try to see what's happening in the sub-surface geology. Because east of Cartersville, when you get up near Lake Allatoona those are some of the oldest rocks in the state. So there's a major fault boundary between those old rocks and the rocks you have in the Cartersville area."
Spearheaded by Kath in 2008, the project received a boost from the assistance of Stan Bearden with New Riverside Ochre Co. Inc.
"Stan Bearden has provided just unprecedented access to New Riverside Ochre's mines," Gray said, adding the information gained was integral to the Cartersville map. "In fact I've heard this firsthand from Stan that as they're mining if they come across anything unique, he would immediately call either Randy Kath or John Costello and get them to come out to the mines and see these exposures firsthand before they remove them through mining.
"As a geologist, this is a great opportunity. I mean, Stan [understands] it. When you see something cool, something of scientific importance, you've got to get the scientists in there, the people that are doing the work so they can look at it and document it."
For Kath, one of the most unique aspects of their project was discovering the complexity of the Cartersville quadrangle.
"I think the description that my colleagues and I all came up with was that the Cartersville district is like a geologic train wreck, where there's just these train cars scattered everywhere and pieces of the geology just all chopped up and scattered all over the place. A lot of that is [because] we've got that fault just to the east of [Cartersville].
"Of course these are very, very old faults so none of them are active any more and have not been active for a long, long time," he said, adding the faults are 250 million years old. "... Now when these faults came in the rocks that were in front of them, imagine like a bulldozer pushing the rocks in front of it, and those big boulders are just tumbling around, so the rocks that are in the area are so mangled up and broken and faulted. At any given time, you can find any given rock. It's just a big mess in there."
Compared to the USGS's Bartow County maps in the 1950s and 1970s, Kath believes the current findings present a truer depiction of the area's geology. In addition to the maps being more detailed than the earlier versions, he credits this to receiving access to New Riverside's property and drilling records.
Although conducted in an era of increased technology, Kath said some of their research techniques still are fundamental in their approach.
"Basically, you walk through the woods and you identify the rocks and you plot spatially where all these outcrops are and with your compass, you measure the angle that they're dipping into the earth and that gives us constraints when we draw our cross sections. So it's really just a lot of walking, driving, visiting old mines -- just leather on the ground."