thumbnail

Evaluation of the horizontal-to-vertical spectral ratio (HVSR) seismic method to determine sediment thickness in the vicinity of the south well field, Franklin county, OH

Ohio Journal of Science

By:
, ,

Links

  • The Publications Warehouse does not have links to digital versions of this publication at this time
  • Download citation as: RIS

Abstract

The horizontal-to-vertical spectral ratio (HVSR) seismic method involves analyzing measurements of ambient seismic noise in three dimensions to determine the fundamental site resonance frequency. Resonance is excited by the interaction of surface waves (Rayleigh and Love) and body waves (vertically incident shear) with the high-contrast acoustic impedance boundary at the bedrock-sediment interface. Measurements were made to determine the method's utility for estimating thickness of unconsolidated glacial sediments at 18 locations at the South Well Field, Franklin County, OH, and at six locations in Pickaway County where sediment thickness was already known. Measurements also were made near a high-capacity production well (with pumping on and off ) and near a highway and a limestone quarry to examine changes in resonance frequencies over a 20-hour period. Although the regression relation for resonance frequency and sediment thickness had a relatively low r 2(0.322), estimates of sediment thickness were, on average, within 14 percent of known thicknesses. Resonance frequencies for pumping on and pumping off were identical, although the amplitude of the peak was nearly double under pumping conditions. Resonance frequency for the 20-hour period did not change, but the amplitude of the peak changed considerably, with a maximum amplitude in the early afternoon and minimum in the very early morning hours. Clay layers within unconsolidated sediments may influence resonance frequency and the resulting regression equation, resulting in underestimation of sediment thickness; however, despite this and other complicating factors, hydrogeologists should consider this method when thickness data are needed for unconsolidated sediments. ?? 2011 by The Ohio Academy of Science. All Rights Reserved.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Evaluation of the horizontal-to-vertical spectral ratio (HVSR) seismic method to determine sediment thickness in the vicinity of the south well field, Franklin county, OH
Series title:
Ohio Journal of Science
Volume
110
Issue:
4
Year Published:
2010
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Ohio Journal of Science
First page:
77
Last page:
85
Number of Pages:
9