COMMENTS

The Sulmona basin is one of the less studied areas of the central Apennines.  Debate 
about the present activity of the Mt. Morrone Fault is open. Sylos-Labini  et al. (1993) 
argue that this fault has had no significant activity  after  Late Pleistocene. In contrast, 
Vittori et al. (1995) contend the fault is active on the  basis of the observation of 
several exposures of offset Late  Pleistocene and Holocene alluvial-fan deposits. 
Unfortunately, better constraints for the timing of faulting are not available. Hence, 
the slip rate of 0.1 mm/y proposed by Vittori et al. (1995) for the Mt. Morrone fault is 
largely uncertain.

Both historical and instrumental seismicity are very limited in the area. The only  
important earthquakes that may have some relation with the Sulmona Source 
occurred on 3 November 1706 and 26 September 1933. The source obtained from 
intensity data of the 1706 earthquake has the same strike as the geologic Sulmona 
Source but is located over 15 km to the east of the Sulmona basin. The 1933 event lies 
even farther to the east. If the 1706 earthquake was not generated by this source and 
the present activity of the Morrone Fault is confirmed, this source could be regarded 
as a potential source for an earthquake that has not taken place at least in the past 
seven centuries.


OPEN QUESTIONS

1) Is the Mt. Morrone fault presently active and is it a potential source for large 
earthquakes?

2) If this is the case, what is its seismic behaviour?

3) Can the controversy between Sylos-Labini et al. (1993), Vittori et al. (1995) and 
Galadini and Galli (2000) be addressed on the basis of more detailed geological and 
paleoseismological  studies?
