Permanent scatterers and seismic motion estimation in the Gargano Peninsula
Silvia Scirpoli(1) and Fabio Rocca(1)
Piazza Leonardo da Vinci 32,
The long series of interferometric SAR data available on the Gargano peninsula allows to establish some experimental relation between the motion before small earthquakes and the coseismic motion.
First, we gather the information on the temblors in this area in the time interval covered by ERS1 and ERS2; the analyzed data set comprehends about 60 events with magnitudes ranging from 1.5 to 4.4 in the Richter scale, each involving at least about 10 – 20 permanent scatterers. We identify, for each location, the fault position, based on the ground motion of the points and tracing the line that optimally separates the local data set in points with antipodal motion. Then, we find an approximate connection between ground motion (coseismic) and earthquake magnitude. Furthermore, we compare the ground motion before the earthquake and the coseismic motion, in order to assess its predictability, based on the ensemble covariance of the temporal data sequences. As expected, coseismic motion is anticorrelated to preseismic motion.
(*) Work done in part for the Laurea in Ingegneria delle Telecomunicazioni