The indicators of earthquakes are in the rocks more than in the earthquakes that precede them - Earth and Poles. This is indicated by Italian research published in the Journal of Geophysical Research.
The research sought to answer very common questions, such as understanding whether precursor signals of earthquakes exist or whether or not many low-energy earthquakes can be considered predictive of strong earthquakes. The researchers' hypothesis is that rock volumes under stress progressively begin to destabilize each other over more or less extended periods and areas, generating small events.