Springwater continuous monitoring in the L'Aquila area in concomitance with the April 2009 seismic swarm in central Italy: Constraining factors to possible deep-seated fluid emissions

A ML = 5.8 earthquake rocked the L'Aquila area on April 6, 2009. Several aftershocks characterized by 5 < ML < 4 followed the main seismic event. The depth of mainshock was about 9 km and the same region has been hit by strong earthquakes during the past centuries. Possible phenomena related to underground fluid dynamics due to the seismic sequence were reported. Sensors capable of monitoring water level variations and temperatures in selected spring sources of Central Italy were placed in the studied area and their data processed. Fluid sensors located at different distances from the epicentral area were differently affected by the seismic sequence. Collected data during the seismic swarm are discussed and compared to contemporary data recorded by satellite-based techniques.

► Groundwaters were monitored during the April 2009 central Italy seismic swarm.
► The existence of postseismic, coseismic and preseismic signals is discussed.
► The signals pattern strongly influence the interpretation of local fluid related phenomena.
► Eventual preseismic crustal deformative processes could be happened far from epicenters.