Publication Date:
2022-08-25
Description:
We examine the tectonic evolution and structural characteristics of the Quaternary
intermontane Mugello, Casentino, and Sansepolcro basins, in the Northern Apennines fold-andthrust
belt. These basins have been classically interpreted to have developed under an extensional
regime, and to mark the extension-compression transition. The results of our study have instead
allowed framing the formation of these basins into a compressive setting tied to the activity of
backthrust faults at their northeastern margin. Syndepositional activity of these structures is
manifested by consistent architecture of sediments and outcrop-scale deformation. After this
phase, the Mugello and Sansepolcro basins experienced a phase of normal faulting extending from
the middle Pleistocene until Present. Basin evolution can be thus basically framed into a two-phase
history, with extensional tectonics superposed onto compressional structures. Analysis of
morphologic features has revealed the occurrence of fresh fault scarps and interaction of faulting
with drainage systems, which have been interpreted as evidence for potential ongoing activity of
normal faults. Extensional tectonics is also manifested by recent seismicity, and likely caused the
strong historical earthquakes affecting the Mugello and Sansepolcro basins. Qualitative comparison
of surface information with depth-converted seismic data suggests the basins to represent discrete
subsiding areas within the seismic belt extending along the axial zone of the Apennines. The
inferred chronology of deformation and the timing of activity of normal faults have an obvious
impact on the elaboration of seismic hazard models.
Description:
Published
Description:
336-356
Description:
2T. Deformazione crostale attiva
Description:
JCR Journal
Description:
open
Keywords:
Northern Apennines
;
Basin evolution
;
structural analysis
;
active tectonics
;
04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
Permalink
