Publication Date:
2024-01-25
Description:
A multidisciplinary approach including archaeological, geophysical, and geological/geomorphological surveys
provided pieces of evidence that allowed us to identify the Sibari fault zone (SFZ) in Northern Calabria (Italy).
The SFZ runs in a ~ NE-SW direction for a length of ~18 km from the Ionian coastline to Terranova da Sibari and
has an oblique normal-dextral kinematics. The envelope of the SFZ is derived from several direct and indirect
evidence resulting in subparallel and locally en-echelon fault traces over a maximum 500 m-wide band, running
at different elevations across hills and flat lands. The SFZ was active since at least the Middle-Upper Pleistocene,
producing faulting of alluvial deposits, marine terraces, drainage incisions, and the archaeological structures of
Sybaris. Given the fault length and assuming a seismogenic behavior, the SFZ is a primary earthquake source
possibly producing moderate to large earthquakes (M ≥ 6). We calculated the average slip rates along the SFZ
based on the ages and on the accumulated displacements of offset streams and marine terraces. The estimates are
of 0.05–0.18 mm/yr and 0.41–0.70 mm/yr for vertical and dextral slip, respectively. Based on both the measured
(min. 30 cm) and the expected value (av. 40 cm) of lateral slip per event, we infer an average recurrence for
surface faulting events on the SFZ of about 700–1000 yrs. The most recent surface faulting earthquake occurred
on the fault is dated 1300–1100 yrs. ago, highlighting that the elapsed time approaches the estimated average
recurrence. Considering these findings, the newly recognized SFZ should be included among the faults that
contain a potential seismic hazard in this poorly known portion of the Ionian sector of northern Calabria.
Description:
Published
Description:
230214
Description:
OST2 Deformazione e Hazard sismico e da maremoto
Description:
JCR Journal
Keywords:
Active faults of Italy
;
Seismic hazard
;
Offset streams
;
Displaced marine terraces
;
Sybaris archaeological site
;
04.04. Geology
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
