1997 Umbria and Marche earthquake

1997 Umbria and Marche earthquake

Photo of the partially collapsed ceiling vault of the Basilica of Saint Francis of Assisi after the earthquake
UTC time	1997-09-26 09:40:26
ISC event	1043512
USGS-ANSS	ComCat
Local date	26 September 1997 (1997-09-26)
Local time	11:40
Magnitude	6.0 Mw
Depth	10 km (6.2 mi)
Epicenter	43.084°N 12.812°E / 43.084; 12.812
Areas affected	Italy (Umbria, Marche)
Max. intensity	MMI X (Extreme)[1]
Casualties	11 dead 100 injured

Shake map

The 1997 Umbria and Marche earthquake occurred in the regions of Umbria and Marche, central Italy on the morning of 26 September. It was preceded by a foreshock almost as strong as the main quake. The foreshock occurred at 02:33 CEST (00:33 UTC), rated M_w5.7, and the second – the main shock – occurred at 11:40 CEST (09:40 UTC), rated M_w 6.0. Their epicentre was in Annifo. The mainshock was assigned X (Extreme) and foreshock VIII (Severe) on the Mercalli intensity scale.^[2]

There were several thousands of foreshocks and aftershocks from May 1997 to April 1998, more than thirty of which had a magnitude more than 3.5. Eleven people are known to have died following the shocks.

List of foreshocks and aftershocks

Only shocks (both foreshocks and aftershocks) with magnitude 5.0 or higher are listed.^[3]

Date (YYYY-MM-DD)	Time (UTC)	Latitude	Longitude	Depth	Magnitude
1997-09-26	00:33:12	43.048° N	12.879° E	10 km (6 mi)	5.7 (Mw )
1997-09-26	09:40:26	43.084° N	12.812° E	10 km (6 mi)	6.0 (Mw )
1997-09-26	09:47:38	43.163° N	12.752° E	10 km (6 mi)	4.7 (Mw )
1997-10-03	08:55:21	43.075° N	12.794° E	10 km (6 mi)	5.3 (Mw )
1997-10-06	23:24:52	43.045° N	12.835° E	10 km (6 mi)	5.5 (Mw )
1997-10-12	11:08:36	42.901° N	12.897° E	10 km (6 mi)	5.3 (Mw )
1997-10-14	15:23:10	42.962° N	12.892° E	10 km (6 mi)	5.6 (Mw )
1997-11-09	19:07:33	42.903° N	12.948° E	10 km (6 mi)	5.0 (Mw )
1998-03-26	16:26:11	43.255° N	12.969° E	10 km (6 mi)	5.4 (Mw )
1998-04-03	07:26:36	43.164° N	12.701° E	10 km (6 mi)	5.2 (Mw )
1998-04-05	15:52:20	43.185° N	12.719° E	10 km (6 mi)	5.0 (Mw )

See also

• List of earthquakes in 1997
• List of earthquakes in Italy
• Earthquake engineering

Notes

1. "M 6.0 – 3 km SSE of Nocera Umbra, Italy". United States Geological Survey. Retrieved 3 July 2021.
2. "M 5.7 – 6 km WSW of Serravalle di Chienti, Italy". United States Geological Survey. Retrieved 3 July 2021.
3. "NEIC: Earthquake Search Results". United States Geological Survey. 2009-10-01. Archived from the original on 2012-05-25. Retrieved 2009-10-01.

Further reading

• Amato, A.; Azzara, R.; Chiarabba, C.; Cimini, G. B.; Cocco, M.; Di Bona, M.; Margheriti, L.; Mazza, S.; Mele, F.; Selvaggi, G.; Basili, A.; Boschi, E.; Courboulex, F.; Deschamps, A.; Gaffet, S.; Bittarelli, G.; Chiaraluce, L.; Piccinini, D.; Ripepe, M. (1998), "The 1997 Umbria-Marche, Italy, Earthquake Sequence: A first look at the main shocks and aftershocks" (PDF), Geophysical Research Letters, 25 (15): 2861–2864, Bibcode:1998GeoRL..25.2861A, doi:10.1029/98GL51842, S2CID 140166678
• Cattaneo, M.; Augliera, P.; De Luca, G.; Gorini, A.; Govoni, A.; Marcucci, S.; Michelini, A.; Monachesi, G.; Spallarossa, D.; Trojani, L.; Xgums (2000), "The 1997 Umbria-Marche (Italy) earthquake sequence: Analysis of the data recorded by the local and temporary networks", Journal of Seismology, 4 (4): 401–414, Bibcode:2000JSeis...4..401C, doi:10.1023/A:1026511209166, S2CID 129453544
• Cinti, F. R. (2009), "The 1997-1998 Umbria-Marche post-earthquakes investigation: Perspective from a decade of analyses and debates on the surface fractures", Annals of Geophysics, 51 (2–3), CiteSeerX 10.1.1.611.4395, doi:10.4401/ag-4450
• Dolce, M.; Masi, A.; Goretti, A. (2018), "Damage to buildings due to 1997 Umbria-Marche earthquake", Seismic Damage to Masonry Buildings, pp. 71–80, doi:10.1201/9780203740040-6, ISBN 9780203740040, S2CID 135235868
• Ripepe, M.; Piccinini, D.; Chiaraluce, L. (2000), "Foreshock sequence of September 26th, 1997 Umbria-Marche earthquakes", Journal of Seismology, 4 (4): 387–399, Bibcode:2000JSeis...4..387R, doi:10.1023/A:1026508425230, S2CID 126729602
• Spence, Robin; d'Ayala, Dina (1999), "Damage Assessment and Analysis of the 1997 Umbria-Marche Earthquakes", Structural Engineering International, 9 (3): 229–233, doi:10.2749/101686699780482014

External links

• CFTI4med Archived 2011-07-22 at the Wayback Machine
• Earthquake Assisi, Italy – Terremoto Assisi, Italia 1997 – The only existing video footage of the quake, showing the moment it destroyed the Basilica of Saint Francis of Assisi.
• The International Seismological Centre has a bibliography and/or authoritative data for this event.