Water-table and discharge changes associated with the 2016-2017 seismic sequence in central Italy: hydrogeological data and a conceptual model for fractured carbonate aquifers

作者:Petitta Marco; Mastrorillo Lucia; Preziosi Elisabetta*; Banzato Francesca; Barberio Marino Domenico; Billi Andrea; Cambi Costanza; De Luca Gaetano; Di Carlo Giuseppe; Di Curzio Diego; Di Salvo Cristina; Nanni Torquato; Palpacelli Stefano; Rusi Sergio; Saroli Michele; Tallini Marco; Tazioli Alberto; Valigi Daniela; Vivalda Paola; Doglioni Carlo
来源:Hydrogeology Journal, 2018, 26(4): 1009-1026.
DOI:10.1007/s10040-017-1717-7

摘要

A seismic sequence in central Italy from August 2016 to January 2017 affected groundwater dynamics in fractured carbonate aquifers. Changes in spring discharge, water-table position, and streamflow were recorded for several months following nine Mw 5.0-6.5 seismic events. Data from 22 measurement sites, located within 100 km of the epicentral zones, were analyzed. The intensity of the induced changes were correlated with seismic magnitude and distance to epicenters. The additional post-seismic discharge from rivers and springs was found to be higher than 9 m(3)/s, totaling more than 0.1 km(3) of groundwater release over 6 months. This huge and unexpected contribution increased streamflow in narrow mountainous valleys to previously unmeasured peak values. Analogously to the L'Aquila 2009 post-earthquake phenomenon, these hydrogeological changes might reflect an increase of bulk hydraulic conductivity at the aquifer scale, which would increase hydraulic heads in the discharge zones and lower them in some recharge areas. The observed changes may also be partly due to other mechanisms, such as shaking and/or squeezing effects related to intense subsidence in the core of the affected area, where effects had maximum extent, or breaching of hydraulic barriers.

  • 出版日期2018-6