1990–91 Alto Mayo earthquakes
UTC time | |
---|---|
1990-05-30 02:34:05 | |
1991-04-05 04:19:49 | |
ISC event | |
370748 | |
334433 | |
USGS-ANSS | |
ComCat | |
ComCat | |
Local date | |
29 May 1990 | |
5 April 1991 | |
Local time | |
21:34 | |
23:19 | |
Magnitude | |
Mw 6.6 | |
Mw 7.1 | |
Depth | |
24.2 km (15 mi) | |
19.8 km (12 mi) | |
Epicenter | 5°58′55″S 77°05′38″W / 5.982°S 77.094°W |
Areas affected | Peru |
Max. intensity | VII (Very strong) |
Foreshocks | Mw 6.5 |
Casualties | 189 dead |
Between the period of May 1990 to April 1991, an earthquake sequence occurred in the Department of San Martín, northern Peru. Three large earthquakes of magnitudes (Mw ) 6.6, 6.5 and 7.1 occurred in the same region, causing extensive damage. At least 189 people were killed in the earthquakes.
Tectonic setting
The coast of Peru lies a 7,000-km-long
Shallow inland crustal earthquakes within the overriding South American Plate are caused by internal deformation of the crust within the
Earthquakes
All three earthquakes corresponded to high-angle reverse faulting at a shallow depth within the South American Plate.[3][4][5] After the Mw 6.6 in May 1990, strong aftershocks were reported, with the strongest measuring Mw 5.7.
Impact
At least 6,000 homes were severely damaged by the earthquake of May 1990, and 135 people were killed. Majority of the structures that suffered damage were constructed from rammed earth and adobe. The town of Soritor was the most affected with 1,100 homes destroyed, or about 90% of the town. The collapse of homes killed many people living in them.[6] An Mw 5.5 aftershock on June 9, 1990, caused one death and destroyed 14 homes.[7] In April 1991, two more earthquakes separated by hours caused further damage in the region.[8] The largest shock measuring 7.1 killed approximately 53 people.[3] A maximum intensity of VII (Very strong) was assigned to the earthquakes.[9]
See also
References
- )
- S2CID 128926791.
- ^ U.S. Geological Survey. Retrieved 2 January 2022.
- U.S. Geological Survey. Retrieved 2 January 2022.
- U.S. Geological Survey. Retrieved 2 January 2022.
- ^ Maskrey, Andrew. "Disaster mitigation in a social vacuum the Alto Mayo earthquare, Peru, May 1990". cidbimena.desastres.hn.
- U.S. Geological Survey. Retrieved 2 January 2022.
- ^ Eduardo Franco; Andrew Maskrey. "Los Desastres del Alto Mayo, Perú, de 1990 y 1991". desenredando.org. Retrieved 2 January 2022.
- ^ Alva-Hurtado J.E.; Meneses J.F.; Chang L.; Lara J.L.; Nishimura T. (1992). "Ground effects caused by the Alto Mayo earthquakes in Peru" (PDF). Tenth World Conference in Earthquake Engineering: 141–145.