Potential early indication of tectonic ground movements by water-well monitoring datasets, with short-term forward modeling

Abstract

Tectonic ground movements in the form ot earthquakes can devastate infrastructure and cause significant casualties once their magnitude is 6 and above. This study investigated early indications of such seismic activity through the correlations with temporal variations in groundwater properties. An automated real-time monitoring network was deployed along the Jordan Rift Valley system, utilizing non-operational wells with confined aquifer conditions near major active faults. Wells were equipped with sensors that monitored water levels, conductivity, and temperature, transmitting the data to a central server. Seismic data from the Geophysical Institute of Israel were correlated with hydrogeochemical measurements to establish mathematical relationships between groundwater properties and earthquake magnitude. Most earthquakes (Mw < 5) showed post-event groundwater reactions or sporadic early indications. However, a Mw 5.5 earthquake with an epicenter 400 km south of monitoring sites produced anomalies several hours before its occurrence. Forward trajectory modeling detected precursory signals in two of four wells, affecting both water level and conductivity. Four independent observations generated an earthquake alert more than an hour before the event, demonstrating the potential of groundwater monitoring for early indication of seismic events.