112 Geophysics in Investigating and Exploring for Mineral, Energy and Groundwater Resources (Posters)

Abstracts are requested for research that incorporates geophysics to investigate and explore for mineral, energy and groundwater resources.

Monday, 20 October 2025
8:00 AM - 5:30 PM
HBGCC, Hall 1

Characterization of Ambient Seismic Data to Define Topography of an Incised Bedrock Valley

Paper number: 112-9
Program: Technical Sessions
Time: 8:00 AM – 8:00 AM

Authors

Abstract

Ambient seismic data, using horizontal-to-vertical spectral ratio (HVSR) methods, have been collected to characterize bedrock depths and geometries in northern Illinois since 2021. Within the last year, we have collected over 300 points of HVSR data on a variety of instruments along a deeply incised bedrock valley and its tributaries. These HVSR soundings have been utilized to redefine interpretations of this valley with important implications for local and regional groundwater resources. In addition to HVSR data, other ground-based and geophysical measurements have been used to refine bedrock depth interpretations. As a part of this campaign, several HVSR soundings were acquired near locations where bedrock depth is known (e.g. boreholes) and were used to develop a highly localized equation to transform frequency data to bedrock depth. The density of soundings and the relationship developed from these localized calibration points has produced more accurate bedrock characterizations than those generated from regional calibration equations. This enables more accurate and higher quality interpretations of bedrock topography that account for local geology and lithology. Continued refinement of bedrock topography in this region using HVSR and other geophysical techniques can contribute to enhanced groundwater resource management in northern Illinois.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6

doi: 10.1130/abs/2025AM-414080

© Copyright 2025 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.