Rockfalls, rock slides and debris flows of
Hickory Nut Gorge, NC
We have secured in-kind support from local practitioners, consultants and academics to help develop and run the conference field trip. Rick Wooten, (Senior Geologist for Geohazards and Engineering Geology at N.C Geological Survey), Dr. Cheryl Waters-Tormey (Western Carolina University, United States) and Appalachian Landslide Consultants are actively working on landslides hazards resulting from PRF in the region of the proposed conference location, and all have confirmed commitment to leading the conference field excursions.
Our one-day field trip will examine a variety of mass wasting features in the Hickory Nut Gorge, a structurally controlled erosional landform incised into the Blue Ridge Escarpment in Rutherford County, western North Carolina. We will see the spectacular but challenging terrain of Chimney Rock State Park that poses hazards from rockfalls, rock slides and debris flows. Examples of these landslide events within the gorge, notably in 1916 and 2018, are well documented. Our field trip leaders will present work by the North Carolina Geological Survey, Western Carolina University, North Carolina State University, Appalachian Landslide Consultants, PLLC, and the U.S. Geological Survey in landslide hazard mapping and research on controls on mass wasting.
Hickory Nut Gorge is an excellent natural laboratory to advance our understanding of the connections between PRF, bedrock structures, landscape evolution, geomorphology, and mass wasting in order to improve public safety. Critically, our proposed field trip will demonstrate how PRF needs to be considered in a landscape with a long legacy of fracture-generating processes.
For example, we will consider the significance of PRF processes in reducing cohesional strength, and how this interacts with inherited fracture sets and brittle vs. ductile bedrock structures to affect the stability of rock masses. To what extent do fluctuations in ambient environmental conditions control PRF, and how and when do these processes cause hazardous failures? Are these distinguishable from those resulting from high-magnitude (seismic and meteorological) events? How can different causal mechanisms of rockfalls be prioritised and addressed in hazard management strategies? These questions will be considered during the field trip, contextualising the work presented throughout the conference and demonstrating the significance, and challenges, of understanding the role that PRF plays in landform and landscape evolution.
Preliminary field trip itinerary
Stop 1: Scenic overview of the Southern Blue Ridge terrain along the Blue Ridge Parkway.
Stop 2: Chimney Rock State Park, south side of Hickory Nut Gorge.
Overview of local geology and mass wasting features.
Walking tour to examine salient features of the Henderson Gneiss, detached exfoliation slabs, overhangs, ductile and brittle rock fabrics.
Hike along Hickory Nut Falls Trail to examine the 2014 rock fall, and large exfoliation faces and detached blocks on the way to Hickory Nut Falls (~2.2 km round trip).
Stop 3: Rumbling Bald Rock Climbing and Bouldering Access Area, Hickory Nut Gorge.
Walking tour of the debris deposits, block fields and cliffs (~2.4 km round trip).
Field Trip Leaders
Rick Wooten, P.G., NORTH CAROLINA GEOLOGICAL SURVEY (ret.)
Bart Cattanach, P.G., NORTH CAROLINA GEOLOGICAL SURVEY
David Korte, Ph.D., P.G., NORTH CAROLINA GEOLOGICAL SURVEY
Jennifer Bauer, P.G., Appalachian Landslide Consultants
Philip Prince, Ph.D., Appalachian Landslide Consultants
Cheryl Waters-Tormey, Ph.D., Western Carolina University
Karl Wegmann, Ph..D, L.G., L.E.G., North Carolina State University