Joint 56th Annual North-Central/ 71st Annual Southeastern Section Meeting - 2022

Paper No. 9-49
Presentation Time: 8:00 AM-12:00 PM


BAXTER, Andrew, Department of Geology, Augustana College, 639 38th St., Rock Island, IL 61201 and WOLF, Michael, Department of Geology, Augustana College, 639 38th Street, Rock Island, IL 61201

Meteorite impacts are regarded as significant megascopic events that can alter the Earth. In addition to obvious crater features, shatter cones are utilized as one of the primary macroscopic indicators of impact events. These conical deformations form within rock through intense pressure produced only by large impact events or nuclear explosions. The Wells Creek crater – located at Cumberland City, Tennessee – provides an excellent location to observe the precise deformation of local Mississippian limestone by an impact event. Shatter cone samples were cut by saw into slices perpendicular to the shatter cone’s c-axis. Each slice was ground and polished on every saw face. A point cloud and 3-D model were created to efficiently visualize the fracture patterns within Wells Creek shatter cones. Samples were photographed within Pix4DCatch on an iPad Pro, and the data imported onto the Pix4D cloud. Sample images were processed within Pix4DCapture to construct a point cloud of the shatter cones. Creation of a point cloud allows for the modeling of the fracture features throughout the rock. The fracture patterns of each slice face were isolated within individual project layers, and then joined to create a single project. Preliminary point cloud models suggest deformation of rock within shatter cone formation is focused within 2 mm of the shatter cone surface. Further observations will be collected upon completion of additional modeling. Ideally, additional samples would be collected and modeled to gain a large-scale view of the pressure waves that radiated outward from the location of impact.