LaGesse is using cores drilled by the U.S. Geological Survey (USGS) and the North Carolina Earth Sciences Coalition plus studies of outcrops to look at rock types from the Paleogene age, their stacking patterns, and how the rocks have changed over time. "We also want to know what happened to the rock -- whether it grew cements or became porous, for example," she says.
One surprise in the course of her research has been the core drilled at Kure Beach in the summer of 2000. "When you drill cores, there are often large missing intervals -- 10 to 20 feet where a section crumbles or, if it's muddy, just washes away," LaGesse explains. But the Kure Beach 1,200-foot long core had approximately 98 percent recovery.
She is looking at a 150-foot interval of the Kure Beach core, which is now at the USGS North Carolina Coastal Plain Office, and two earlier cores from the region that are at Virginia Tech. LaGesse is studying the cores in detail using microscope thin sections of the rocks as well as chemical and isotopic studies. To show how all the cores and outcrops are interconnected, she will present a regional cross section of the Paleogene coast. Some sections of the cores being studied are up to 350 feet in depth.
The long-range goal of the research is to produce models that would have world-wide applications in environments similar to the Paleogene of North Carolina, that is, an open shelf in a sub-tropical climate with a boundary current. The research plans to answer important questions about how the rocks manifested themselves in these environments, "so people in another part of the world can use it to compare to the same period in their area," LaGesse says.
The poster, "Facies, sequence stratigraphy, and diagenesis of Paleogene continental shelf facies, North Carolina, USA," will be presented from 8 a.m. until noon on Tuesday, Oct. 29, in the Exhibit Hall of the Colorado Convention Center.
Contact for more information: Jenny LaGesse, jlagesse@vt.edu, 540-231-4515
Jenny LaGesse's major professor is J. Fred Read, 540-231-5124, jread@vt.edu
PR Contact: Susan Trulove, strulove@vt.edu, 540-231-5646