-In this study, surface and subsurface geological data are integrated with seismological data in order to reconstruct a structural model for the September-October 1997 Colfiorito earthquakes. The seismic sequence is mainly controlled by two major SW-dipping normal faults outcropping in the area (M. Pennino-M. Prefoglio and M.Civitella-Preci faults). The activated faults detach, at depth, on a common east-dipping low-angle normal fault, the Altotiberina Fault (AF). The AF is interpreted as the base of an active hangingwall block which is stretching toward NE. The decrease in maximum depth of the earthquake foci from the Colfiorito area (about 8 km) to the Sellano area (about 6 km), suggested by the available seismological data, could be related to the eastward-deepening geometry of the AF detachment. The seismic fault planes, inferred from focal mechanisms and aftershock distributions, are characterised by a moderate dip (average 40◦) toward SW, which appears to be independent from the presence of pre-existing thrust planes.

A geological model for the Colfiorito earthquakes (September-October 1997, Central Italy)

BONCIO, Paolo
;
LAVECCHIA, Giuseppina
2000-01-01

Abstract

-In this study, surface and subsurface geological data are integrated with seismological data in order to reconstruct a structural model for the September-October 1997 Colfiorito earthquakes. The seismic sequence is mainly controlled by two major SW-dipping normal faults outcropping in the area (M. Pennino-M. Prefoglio and M.Civitella-Preci faults). The activated faults detach, at depth, on a common east-dipping low-angle normal fault, the Altotiberina Fault (AF). The AF is interpreted as the base of an active hangingwall block which is stretching toward NE. The decrease in maximum depth of the earthquake foci from the Colfiorito area (about 8 km) to the Sellano area (about 6 km), suggested by the available seismological data, could be related to the eastward-deepening geometry of the AF detachment. The seismic fault planes, inferred from focal mechanisms and aftershock distributions, are characterised by a moderate dip (average 40◦) toward SW, which appears to be independent from the presence of pre-existing thrust planes.
File in questo prodotto:
File Dimensione Formato  
Boncio-Lavecchia2000_Article_AGeologicalModelForTheColfiori.pdf

Solo gestori archivio

Tipologia: PDF editoriale
Dimensione 1.37 MB
Formato Adobe PDF
1.37 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11564/122449
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 53
  • ???jsp.display-item.citation.isi??? 50
social impact