EAGER: Forecasting Subsequent Seismicity using Double-Difference Tomography

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

Imaging technologies are routinely used within the medical field yet have not been adapted for use in the study of the earth. Of particular consequence is the study of seismicity, either naturally occurring or triggered by human activity. The rock mechanics community lacks a well-founded tool for imaging and assessing the potential for seismicity within a rock mass. Seismicity is a result of unstable equilibrium due to increased depth of excavation and/or increased extraction ratio. Both of these phenomena result in high-stress concentrations. Double-difference tomography, a recently developed technology, has been used by the PI to image stress redistribution within a rock mass more clearly than ever before. It is hypothesized that by combining an understanding of expected stress redistribution (through lithologic mapping, lab testing, and numerical modeling) with observed stress redistribution (from double-difference tomography) a forecast of subsequent seismicity can be made. This project will test this hypothesis using data from a deep, underground nickel mine. Because this project is based upon a very novel hypothesis that has potential to transform existing abilities, the proposal is particularly well-suited for an NSF Early-concept Grant for Exploratory Research (EAGER). One graduate student will be supported by project funding and results will be disseminated through journal papers and conference proceedings.