Imagine that Ohio is located south of the equator in a tropical climate with a saltwater sea extending from central Ohio to eastern Pennsylvania and another sea covering northwestern Ohio and Michigan.
That is what scientists think it was like here 395,000,000 years ago—long before dinosaurs roamed the earth. Then, Ohio was part of a land mass named Euroamerica that included North America, Greenland, Scandinavia, Europe, and Eastern Russia. Limestone formed in these warm, shallow seas. Later, the geological record was partially destroyed when much of this rock was eroded—leaving behind limestone in northern Ohio, a small patch near Bellefontaine, and a band running through central Ohio.
Today, Ohio Wesleyan professor and paleontologist Keith Mann, Ph.D., and student Jen Schmitt are using modern research methods in combination with previous research findings from the paleontological community to answer old questions about the ancient seas that covered Ohio. The technique is known as High-Resolution Conodont Biostratigraphy. This is an independent student research project, and Schmitt’s senior project.
“We are trying to determine when—and how quickly—the sea-level changes occurred in Ohio,” Mann says. “Understanding precisely when this limestone was deposited will help elucidate rates and the extent of global sea-level change, which will ultimately aid in our understanding of present-day sea-level changes.”
Mann and Schmitt received funding through an OWU Theory-to-Practice grant for laboratory equipment and to travel to northwest Ohio in May for a week to obtain limestone samples from the Dundee Limestone exposed in the Whitehouse Quarry.
They chose to work on the Dundee Limestone because geologists thought it was deposited at about the same time as other limestones near Bellefontaine and central Ohio. They are comparing the fossils they extracted from the rock with fossils from other areas of Ohio to determine whether the rocks from the Whitehouse Quarry are the same vintage as those near Bellefontaine and central Ohio.
The limestone samples are dissolved in an acid bath (a new research technique), and the leftover silt-sized residue is picked through to find tiny fossils of teeth-like structures from primitive vertebrates related to the lamprey. These long-extinct vertebrates were up to several inches in length, and their tooth-like fossils are called conodonts. They are so tiny that several conodonts can fit on the head of a pin. So far, Schmitt has processed half the limestone rock samples and is already finding diagnostic conodonts.
“As we knit the history of these three areas back together, our research will aid in our understanding of past global sea-level changes,” Mann says.
Schmitt says, “This research allows me to achieve the theory-into-practice principle. You get hands-on experience getting into the depth of the science.
“I will be writing a research paper based on our procedure and findings,” continues Schmitt, a junior from Spring, Texas. “Usually you don’t get to write such a paper until graduate school.” She is majoring in geology and accounting, and earning minors in women’s and gender studies and in economics management.
“Actually, the critical thinking between geology and accounting (my other major) is very similar,” Schmitt says. “Both have foundational units, both tell a story, and ultimately you put the pieces together to form a new picture. I have an extreme love for paleontology, and Dr. Mann’s enthusiasm is so contagious!”
Mann hopes that Schmitt will present the results of their research in a joint paper in fall 2011 at the national meeting of the Geological Society of America.
Samples and information obtained for this project also will provide support for student research in Mann’s “Sedimentology and Stratigraphy” class, taught during fall semester in even-numbered years. The conodonts will enhance OWU’s paleontological laboratory, and the research will continue on an ongoing basis.