Cost-effective Groundwater Monitoring Using Nodal Geophones: Updates From a Case Study in the Upper Mississippi Embayment
Description:
The aquifer system of the Upper Mississippi Embayment (UME) supports the water needs of agriculture, industry, and an increasing population in a large five-state region of the central United States. However, increasing demand coupled with unregulated use may threaten the long-term sustainability of this vital resource, highlighting the need for reliable groundwater monitoring across this region. Seismic interferometry offers a promising solution to meet this need by measuring spatiotemporal variations in seismic wave speeds from which changes in groundwater storage can be inferred. We are undertaking a multi-year interferometric investigation of a ~2,000 km2 area in the Kentucky part of the UME, which hosts multiple aquifers from the surface to depths up to ~600 m. Based on previous studies and preliminary work in the larger UME, the necessary resolution requires both a relatively dense array of seismometers (~10 km spacing or less) and recordings of ambient noise at frequencies ≤0.2 Hz. To satisfy these requirements in our study area, we plan to deploy a dense array of cost-effective nodal instruments (nodes) that can reliably record weak, low-frequency seismic waves. We evaluated the performances of three types of nodal instruments through temporary deployments at two sites in the project area with differing depths to the basal bedrock confining layer (~200 m and ~500 m). Comparisons of waveforms and power spectral densities from the nodal recordings against those from co-located traditional broadband seismometers revealed that two types of nodes record ambient vibrations at frequencies ≤0.2 Hz, establishing that low-cost nodes are suitable for this project. We have also retrieved preliminary inter-station reference Green’s Functions from stacked cross-correlograms calculated from station pairs near a deep (>100 m) groundwater monitoring well. We will present an overview of the multi-year project, and results from the nodal geophone assessment and the retrieved Green’s Functions.
Session: Geophysics in a Changing World: Monitoring Applications from Seismology and Beyond [Poster]
Type: Poster
Date: 4/15/2025
Presentation Time: 08:00 AM (local time)
Presenting Author: Seth
Student Presenter: No
Invited Presentation:
Poster Number: 44
Authors
Seth Carpenter Presenting Author Corresponding Author seth.carpenter@uky.edu University of Kentucky |
Felix Rodriguez Cardozo felixr1@usf.edu University of South Florida |
Jonathan Schmidt jon.schmidt@uky.edu University of Kentucky |
Jochen Braunmiller jbraunmiller@usf.edu University of South Florida |
Edward Woolery ewoolery@uky.edu University of Kentucky |
Zhenming Wang zmwang@uky.edu University of Kentucky |
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Cost-effective Groundwater Monitoring Using Nodal Geophones: Updates From a Case Study in the Upper Mississippi Embayment
Category
Geophysics in a Changing World: Monitoring Applications from Seismology and Beyond