%0 Journal Article %1 amato_etal:1998 %A Amato, A. %A Azzara, R. %A Chiarabba, C. %A Cimini, G. B. %A Cocco, M. %A Di Bona, M. %A Margheriti, L. %A Mazza, S. %A Mele, F. %A Selvaggi, G. %A Basili, A. %A Boschi, E. %A Courboulex, F. %A Deschamps, A. %A Gaffet, S. %A Bittarelli, G. %A Chiaraluce, L. %A Piccinini, D. %A Ripepe, M. %D 1998 %J Geophysical Research Letters %K geophysics seismology %N 15 %P 1861--1864 %R 10.1029/98GL51842 %T The 1997 Umbria-Marche, Italy, earthquake sequence: A first look at the main shocks and aftershocks %U http://dx.doi.org/10.1029/98GL51842 %V 25 %X A long sequence of earthquakes, six with magnitudes between 5 and 6, struck Central Italy starting on September 26, 1997, causing severe damages and loss of human lives. The seismogenic structure consists of a NW-SE elongated fault zone extending for about 40 km. The focal mechanisms of the largest shocks reveal normal faulting with NE-SW extension perpendicular to the trend of the Apennines, consistently with the Quaternary tectonic setting of the internal sector of the belt and with previous earthquakes in adjacent regions. Preliminary data on the main shocks and aftershocks show that extension in this region of the Apennines is accomplished by normal faults dipping at low angle (\~40 deg) to the southwest, and confined in the upper \~8 km of the crust. These normal faults might have reactivated thrust planes of the Pliocene compressional tectonics. The aftershock distribution and the damage patterns also suggest that the three main shocks ruptured distinct 5 to 15 km-long fault segments, adjacent and slightly offset from one another.

@article{amato_etal:1998, abstract = {A long sequence of earthquakes, six with magnitudes between 5 and 6, struck Central Italy starting on September 26, 1997, causing severe damages and loss of human lives. The seismogenic structure consists of a NW-SE elongated fault zone extending for about 40 km. The focal mechanisms of the largest shocks reveal normal faulting with NE-SW extension perpendicular to the trend of the Apennines, consistently with the Quaternary tectonic setting of the internal sector of the belt and with previous earthquakes in adjacent regions. Preliminary data on the main shocks and aftershocks show that extension in this region of the Apennines is accomplished by normal faults dipping at low angle (\~{}40 deg) to the southwest, and confined in the upper \~{}8 km of the crust. These normal faults might have reactivated thrust planes of the Pliocene compressional tectonics. The aftershock distribution and the damage patterns also suggest that the three main shocks ruptured distinct 5 to 15 km-long fault segments, adjacent and slightly offset from one another.}, added-at = {2012-09-01T13:08:21.000+0200}, author = {Amato, A. and Azzara, R. and Chiarabba, C. and Cimini, G. B. and Cocco, M. and Di Bona, M. and Margheriti, L. and Mazza, S. and Mele, F. and Selvaggi, G. and Basili, A. and Boschi, E. and Courboulex, F. and Deschamps, A. and Gaffet, S. and Bittarelli, G. and Chiaraluce, L. and Piccinini, D. and Ripepe, M.}, biburl = {https://www.bibsonomy.org/bibtex/256208fbae6302d9c0672eed862d2bf8b/nilsma}, doi = {10.1029/98GL51842}, interhash = {3a6ed5e77889563126afd0da23bbc991}, intrahash = {56208fbae6302d9c0672eed862d2bf8b}, issn = {0094-8276}, journal = {Geophysical Research Letters}, keywords = {geophysics seismology}, number = 15, pages = {1861--1864}, timestamp = {2021-02-09T13:25:06.000+0100}, title = {The 1997 Umbria-Marche, Italy, earthquake sequence: A first look at the main shocks and aftershocks}, url = {http://dx.doi.org/10.1029/98GL51842}, volume = 25, year = 1998 }