Extracting Coseismic Signals from Groundwater Level

David S. Harte, Mark Bebbington, & Ting Wang

Published September 20, 2011, SCEC Contribution #6142

There has been no statistical examination of the possible link between earthquakes and the transient hydrological response of a well with potentially hundreds of responses. We propose an algorithm for automatically detecting anomalous transient changes in groundwater level (signals) based on a moving average of the variance of the first differences in water level. This is tested on 4 years of groundwater level data sampled at 1-minute intervals (approximately 2 million data) from the Tangshan Well, ∼100 km southeast of Beijing, using the global catalog of earthquakes of minimum magnitude 6.0 during the same period (600 events). We investigate the relationship between the extracted signals and the arrival times of various seismic waves, in particular, the earliest P phase, S phase, Love wave, and Rayleigh wave arrivals. The detection probability is estimated as a function of the earthquake characteristics magnitude, well-epicenter distance, depth, and azimuth from the well.

Citation
Harte, D. S., Bebbington, M., & Wang, T. (2011). Extracting Coseismic Signals from Groundwater Level. Mathematical Geosciences, 43(7), 799-817. doi: 10.1007/s11004-011-9356-3.