Toward Large-Scale Groundwater Monitoring with Seismic and Geodetic Data: Case Study and Future Directions

Session: Advances in Seismic Interferometry: Theory, Computation and Applications [Poster]
Type: Poster
Date: 4/30/2020
Time: 08:00 AM
Room: Ballroom
Description: 

Over 2 billion people worldwide suffer from water stress. Although groundwater in large aquifer systems is often relied upon as a water source, it is one of the least well-known components of the water cycle. Here, we document a relationship between subsurface seismic response and groundwater levels (GWLs) in two large aquifers of the U.S. (the Gulf Coast Aquifer System and the Florida Aquifer System). Auto- and cross-component correlation of ambient noise, as well as receiver functions computed at a single seismic station show consistent correlations with GWLs on long timescales. For example, we find that a ~15 m groundwater level rise at a well in the Gulf Coast Aquifer System produces a 1.2% increase in P-wave velocity (V_P) determined from autocorrelations and causes variations in power spectral density of teleseismic receiver functions. We present a simple physical model to relate aquifer properties, GWL changes and seismic velocities. We find that GWL changes affect V_P more strongly than S-wave (V_S) velocities and discuss how these differences manifest in correlation tensors. We assess the success of this approach using long-term recordings at seismic stations in aquifers elsewhere in the U.S. We discuss the potential for mapping key hydraulic parameters (e.g., porosity and hydraulic conductivity) using a joint analysis of seismic and geodetic data, which leverages different sensitivities to the distribution of water with depth.

Presenting Author: Doyeon Kim

Authors