As recent as Monday, a group of colleagues and myself published a paper in Nature Geoscience, showing proof of a positive correlation between the slip distribution occurred during the 2011 Lorca earthquake and the mid-term (50-years) stress changes due to a crustal unloading groundwater mass removal process. This finding is quite exciting, hitting the media and apparently causing lot of discussion. However, I regret to see some news reports highlighting the word “caused”, something we didn’t say nor endorse in our study. The long-term tectonic stresses accumulated by the Alhama de Murcia Fault were much larger (0.5-2 MPa) than the simulated stress change due to the unloading process (0.01 MPa). So, it is incorrect to say that the groundwater extraction caused the event. The Alhama de Murcia fault was late in its earthquake cycle, something that perhaps could helped to increase its susceptibility to external forcing. But, our data modelling suggests correlation and therefore we proposed that the unloading stress changes were sufficient to control the way in which the tectonic stress released.
I hope that in the future, we could find other examples of such relationship, as it could have profound implications. In that regard, J.-P. Avouac commented our paper and expose possible future implications of our discovery link here.