The Italian CMT dataset from 1977 to present

The INGV-Harvard European-Mediterranean Regional Centroid Moment Tensor (RCMT) Catalog collects solutions routinely
computed since 1997 for earthquakes with moderate magnitude (4.5 ≤ M ≤ 5.5) in the Mediterranean region. The database represents
an extension to smaller magnitudes of the Harvard global CMT catalog, based on analysis of seismograms recorded at
regional distance, and modeling of intermediate period surface waves. The catalog includes about 600 events, 200 of which in the
Italian region. This study extends the catalog back in time, for the Italian region, as long as made possible by available digital
data – i.e. since 1977 – with the same analysis and inversion method used for current seismicity. As a result, we present here 65
new moment tensors, for years between 1977 and 1997. These solutions represent 45% of the total number of events analyzed,
the existing seismograms being often too scarce to allow a stable solution. The new dataset includes events in many seismic zones
where moderate seismicity had previously been scarcely documented, e.g., the Po Plain, the Central to Southern Apennines and the
Adriatic Sea. The complete dataset, including previously determined RCMTs and CMTs, represents the seismic deformation in the
Italian area during the last 25 years.

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