Vibration damage of rock landforms: contribution of anthropogenic and natural energy sources to bedrock fracture and erosion

University Of Utah, Salt Lake City UT

Investigators

Abstract

This project investigates damage created by natural and anthropogenic vibration sources in freestanding rock landforms, such as arches, towers and fins. While the ability of earthquakes to trigger slope failure is well known, comparably little attention has been given to the role of human vibration sources in driving rock damage, as well as the cumulative effects of repeated exposure on the long-term stability of rock landforms. The investigators identify several sources able to excite resonance and generate damage: earthquakes, wind, trucks, trains, helicopters, and sonic booms. To achieve broader impacts, the investigators will work with National Park Service managers to share knowledge and materials for public dissemination, including animations and sound files, as well as conduct management briefings on potential effects of anthropogenic vibrations on the long-term stability of geologic features. They will train students at the bachelor's, master's, and doctoral levels, including groups underrepresented in STEM, and conduct outreach activities with Native American tribal organizations. They will develop a new science-art collaboration that will result in a publicly shared art piece communicating the dynamic nature of Earth surface landforms. The investigators will develop methodology to assess vibrational modes of geological features from ambient resonance sensing, compile vibration source energy characterizations from seismic and infrasound field data, generate important new data sets measuring resonance induced by select transit sources, and create new statistical analyses of monitoring data to contextualize individual events and sources. They will then use monitoring data to parameterize a broadly-applicable, conceptual fracture mechanics model generating quantitative comparison of the long-term cumulative impact of purely natural or added anthropogenic vibration energy in driving rock mass damage. The analysis creates a unique opportunity for quantitative comparison of anthropogenic and natural contributions to the mechanical degradation of geological features, including the cumulative effects of vibration events across a broad range of magnitudes. This study focuses on culturally valuable rock features in Utah, but the results will be broadly applicable across the world. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.