1887 Sonora earthquake

1887 Sonora earthquake
Date 3 May 1887 (1887-05-03)
Magnitude 7.6 Mw[1]
Depth 80 km
Countries or regions Mexico, USA
Casualties 51

The 1887 Sonora earthquake occurred at 22:13 UCT on 3 May in the Teras mountain range of northwestern Mexico. It was widely felt, with some damage being recorded up to 200 km from the epicenter in both Mexico and the United States. The earthquake had an estimated magnitude of 7.6 and caused 42 casualties in the town of Bavispe and 51 overall.[2] It was the only historical earthquake to cause considerable damage in Arizona.[3] The 1887 Tombstone Arizona newspapers mentioned lesser quakes (aftershocks) on August 27, 1887 and November 11, 1887.

Contents

Tectonic setting

The earthquake was located near the southern end of the extensional Basin and Range Province. The western margin of the Sierra Madre Occidental plateau is formed by a series of west-dipping normal faults, over a distance of at least 300 km. The earthquake occurred within this zone.[4]

Damage

Towns near the epicenter suffered significant damage, particularly in Bavispe, where most houses were destroyed and 42 of the town's 700 inhabitants were killed. Houses of adobe construction were also destroyed in Tepic and Moctezuma. The houses were roofed with heavy log rafters that were untied to the adobe walls and fell in when the walls collapsed.[5] The earthquake triggered many rockfalls and landslides and caused ground fissures. Moderate to severe damage occurred in northeastern Sonora, northwestern Chihuahua, southwestern New Mexico, southeastern Arizona and the westernmost part of Texas.[1]

Characteristics

The earthquake was associated with a surface rupture consisting of three segments with a combined length of 101.8 km, the longest normal fault rupture recorded for an earthquake in historic times.[6] The three faults that ruptured were the Pitáycachi, Teras, and Otates faults from north to south.[7] The magnitude of the event has been estimated as 7.6 on the moment magnitude scale from an analysis of an isoseismal map drawn up for this event, following a re-evaluation of earlier estimates of felt intensity.[1]

There was a prolonged sequence of aftershocks that are interpreted to continue to the present. Particularly large aftershocks (about magnitude 5) occurred on 26 May 1907, 17 May 1913 and 18 and 19 December 1923.[8]

References

  1. ^ a b c Suárez, G.; Hough S.E. (4 November 2008). "Reevaluation of the Macroseismic Effects of the 1887 Sonora, Mexico Earthquake and its Magnitude Estimation". http://usuarios.geofisica.unam.mx/cruz/Sismociones_Libres/Biblio_Sismocion/Sonora_v5.pdf. Retrieved 3 August 2010. 
  2. ^ Wong, I.G. (2009). "Earthquakes in New Mexico". New Mexico Earth Matters (New Mexico Bureau of Geology and Mineral Resources). http://geoinfo.nmt.edu/publications/periodicals/earthmatters/9/EMv9n1_09.pdf. Retrieved 1 November 2010. 
  3. ^ McGarvin, T.G. (1987). "The 1887 Sonoran earthquake". Arizona Bureau of Geology and Mineral Technology Fieldnotes 17 (2). http://www.azgs.az.gov/Hazards_ocr/earthquakes/1887%20Sonoran%20Earthquake-%20Not%20Our%20Fault.pdf. 
  4. ^ Suter, M.; Contreras J. (2002). "Active Tectonics of Northeastern Sonora, Mexico (Southern Basin and Range Province) and the 3 May 1887 Mw 7.4 Earthquake". Bulletin of the Seismological Society of America 92 (2): 581–589. doi:10.1785/0120000220. http://www.bssaonline.org/cgi/content/abstract/92/2/581. Retrieved 11 August 2010. 
  5. ^ Kovach, R.L. (2004). Early earthquakes of the Americas. Cambridge University Press. pp. 160-€“164. ISBN 978-0-521-82489-7. http://books.google.co.uk/books?id=FzmyiyI3_wIC&pg=PA164&dq=1887+sonora+earthquake&hl=en&ei=SB9jTIb4LaKT4gbkxbzACg&sa=X&oi=book_result&ct=result&resnum=4&ved=0CEAQ6AEwAw#v=onepage&q=1887%20sonora%20earthquake&f=false. Retrieved 11 August 2010. 
  6. ^ Suter, M. (2006). "Contemporary Studies of the 3 May 1887 Mw 7.5 Sonora, Mexico (Basin and Range Province) Earthquake". Seismological Research Letters 77 (2): 134–147. doi:10.1785/gssrl.77.2.134. http://srl.geoscienceworld.org/cgi/content/extract/77/2/134. 
  7. ^ Suter, M. (2008). "Structural confi guration of the Teras fault (southern Basin and Range Province) and its rupture in the 3 May 1887 MW 7.5 Sonora, Mexico earthquake". Revista Mexicana de Ciencias Geológicas 25 (1): 179–195. http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.112.830. Retrieved 3 August 2010. 
  8. ^ Castro, R.R.; Shearer P.M., Astiz L., Suter M,, Jacques-Ayala & Vernon F. (2010). "The Long-Lasting Aftershock Series of the 3 May 1887 Mw 7.5 Sonora Earthquake in the Mexican Basin and Range Province". Bulletin of the Seismological Society of America 100 (3): 1153–1164. doi:10.1785/0120090180. http://www.geo.arizona.edu/gsat/1887eq/scientific/Castro_etal_2010_BSSA.pdf. Retrieved 5 May 2011.