Investigating Spectral Characteristics of Mining-Induced Seismicity

Details

• Personal Author:
  Kyeremeh BD
• Description:
  A broader understanding of mining-induced seismicity (MIS) has the potential to help improve strategies for risk reduction and mine ground control safety. To improve understanding of MIS, seismic source discrimination can be used to identify the probable mechanism of failure. One approach to seismic source discrimination is through spectral analysis, the evaluation of seismic waves in the frequency domain. In this study, the spectral characteristics of 27 seismic events that occurred between 2017 through 2020 in the Green River Basin study region (GRB) in southwest Wyoming and 265 seismic events occurring between 2017 through 2019 in the Book Cliffs study region (BC) in east-central Utah were investigated. In each region, waveforms recorded on broadband stations within a search radius of 100 km of each event were analyzed. While requiring the ratio of the pre-event noise to the signal of interest was greater than (or equal to) two for each waveform, a P-wave (signal) window was defined and transformed into frequency. These spectra were fit to a model which accounts for source and path effects. The source term of the model assumes a double-couple mechanism, which is typical for natural tectonic earthquakes. The model is minimized to the spectra using three parameters: the long period spectral plateau, corner frequency, and attenuation operator. A basic statistical analysis was conducted on the model parameters to evaluate the potential to discriminate among different seismic sources, including tectonic seismicity and MIS, in each study region. In the GRB, events with depths less than 0 km are better fit by spectral models with lower corner frequencies and higher attenuation compared to events with depths greater than 0 km. This observation might imply that there are at least two dominant source types recorded from the GRB during the time covered by this study. Based on the same spectral modeling approach as performed on the GRB data, distinguishing more than one source type is ambiguous in the BC. However, in the BC, some events with depths less than 0 km have relatively large corner frequencies. Overall, based on depths, there was a distinction in the spectral models in the GRB; however, no distinct separation was observed in the spectral models in the BC. [Description provided by NIOSH]
• Subjects:
  Occupational Health Safety
• Keywords:
  Earthquakes Failure Analysis Geotechnical Engineering Ground Stability Mining Engineering Rock Mechanics
• Publisher:
  University of Utah
• Document Type:
  Text
• Funding:
  Contract
• Genre:
  Thesis
• Place as Subject:
  OSHA Region 8 ; Utah ; Wyoming
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-110
• NIOSHTIC Number:
  nn:20068886
• Citation:
  Salt Lake City, UT: University of Utah, 2021 Dec; :1-110
• Federal Fiscal Year:
  2022
• Performing Organization:
  University of Utah
• Peer Reviewed:
  False
• Start Date:
  20160901
• Source Full Name:
  Investigating spectral characteristics of mining-induced seismicity
• End Date:
  20200831
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:7f71b8b880187d04a4bac1c660f3db43c99f44d53cd50ae6e5c97d6884794e8708f440608d88abce29155a8f4f4af438b2c92b77ab4fd7e9fec0ac72feef6c64
• Download URL:
  https://stacks.cdc.gov/view/cdc/207451/cdc_207451_DS1.pdf
• File Type:
  [PDF - 1.16 MB ]