Publication Date:
2017-04-04
Description:
Northern Apulia is an emerged portion of the Adriatic microplate, representing the foreland–foredeep area of a stretch of the
Apennine chain in southern Italy. The interaction between the relatively rigid microplate and the contiguous more deformable
domains is responsible for the intense seismicity affecting the chain area. However strong, sometimes even disastrous, earthquakes
have also hit northern Apulia on several occasions. The identification of the causative faults of such events is still unclear and
different hypotheses have been reported in literature. In order to provide guidelines and constraints in the search for these
structures, a comprehensive re-examination and reprocessing of all the available seismic data has been carried out taking into
consideration 1) the characteristics of historical events, 2) the accurate relocation of events instrumentally recorded in the last
20 years, 3) the determination of focal mechanisms and of the regional stress tensor.
The results obtained bring to light a distinction between the foreland and foredeep areas. In the first region there is evidence of a
regional stress combining NWcompression and NE extension, thus structures responsible for major earthquakes should be searched for
among strike–slip faults, possibly with a slight transpressive character. These structures could be either approximately N–S oriented
sinistral or E–Wdextral faults. In the foredeep region there is a transition toward transtensive mechanisms,with strikes similar to those of
the previous zone, or maybe also towardsNWoriented normal faults,more similar to those prevailing in the southern Apennine chain in
relation to a dominant NE extension; this appears to be the effect of a reduction of the NW compression, probably due to a decrease in
efficiency of stress transmission along the more tectonised border of the Adriatic microplate.
Description:
Published
Description:
9 - 35
Description:
3.2. Tettonica attiva
Description:
JCR Journal
Description:
reserved
Keywords:
Northern Apulia
;
Historical earthquakes
;
04. Solid Earth::04.06. Seismology::04.06.03. Earthquake source and dynamics
;
04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
