Tracking spatial and temporal variations of terrestrial water storage in central Oklahoma using ambient seismic noise

Shuo Zhang, Bingxu Luo, Yehuda Ben-Zion, Yujie Zheng, David Lumley, & Hejun Zhu

Published September 10, 2023, SCEC Contribution #12946, 2023 SCEC Annual Meeting Poster #044

Significant imbalances in terrestrial water storage (TWS) and severe drought have been observed around the world as a consequence of climate change. Improving our ability to monitor TWS and drought is critical for water-resource management and water-deficit estimation. In this study, we utilize continuous seismic ambient noise to monitor the spatial and temporal evolution of near-surface seismic velocity (dv/v) in central Oklahoma from 2013 to 2022. The temporal variation of dv/v is found to be negatively correlated with gravitational measurements and groundwater levels, showing the impact of groundwater storage on seismic velocities over multi-year timescales, which can be potentially explained through changes of pore-pressure or bulk density near the Earth’s surface. In addition, the seasonal variation of measured dv/v can be explained by using the thermo-elastic response to atmospheric temperature changes. Furthermore, the occurrences of droughts appear coincidently with local peaks of dv/v, suggesting the potential of using near-surface velocity changes to monitor droughts. Leveraging recent progresses on calculating sensitivity kernel of coda wave interferometry, we project dt/t onto the spatial domain. Our result is consistent with Earth's surface deformation measured by InSAR. This observation further demonstrates the sensitivity of near-surface seismic velocity to the migration of groundwater in central Oklahoma. Considering numerous permanent seismometers deployed all around the world, continuous seismic recordings can potentially improve our capability on monitoring distributions and variations of water resources near the Earth’s surface.

Citation
Zhang, S., Luo, B., Ben-Zion, Y., Zheng, Y., Lumley, D., & Zhu, H. (2023, 09). Tracking spatial and temporal variations of terrestrial water storage in central Oklahoma using ambient seismic noise. Poster Presentation at 2023 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology