Publication Date:
2022-06-09
Description:
Young and tectonically active chains like the Central Apennines (Italy) are featured by high structural complexity
as a result of the overprint of subsequent deformational stages, making interpretation of seismotectonics
challenging.
The Central Apennines are characterized by the stacking of tectono-sedimentary units organized in thrust
sheets. However, extensional tectonics is currently affecting the axial sector of the thrust belt, mostly expressing
in extensional earthquakes.
Using a large subsurface dataset acquired for hydrocarbon exploration in the region struck by the 2016–2017
Central Italy seismic sequence, we built a comprehensive 3D geological model and compared it with the
seismicity.
The model primarily shows a series of thrusts developed during the Miocene-Pliocene Apennines orogenesis
and inherited normal faults developed during the Mesozoic extensional phase and the Miocene foreland flexural
process. These normal faults were segmented and transported within the thrust sheets, and sometimes they still
show a clear surface expression.
The succession of tectonic stages resulted in a widespread reactivation of inherited structures, sometimes
inverting their kinematics with different styles and rates, and disarticulating pre-existing configurations.
Such evolution has a strong impact on the seismicity observed in the area, as demonstrated by some examples
that show how the seismicity is aligned on segments of inherited faults, both compressional and extensional.
Their reactivation can be explained by their favorable orientation within the current extensional stress field.
Results feed the debate about the seismogenic potential of faults identified both at depth and surface, which
can impact the seismic hazard of the Apennines.
Description:
Published
Description:
228861
Description:
1T. Struttura della Terra
Description:
2T. Deformazione crostale attiva
Description:
4T. Sismicità dell'Italia
Description:
JCR Journal
Keywords:
Normal faults
;
Thrust sheets
;
Inherited faults
;
Earthquakes
;
Central Apennines
;
3D geological model
;
04.07. Tectonophysics
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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