The 1996 Chimbote earthquake occurred on February 21 at 07:51 local time about 130 km off the coast of northern Peru, near the Peru–Chile Trench. The earthquake had a moment magnitude (Mw) of 7.5 and occurred at 25.0 km (15.5 mi) depth.[2]
  | |
| UTC time | 1996-02-21 12:51:01 |
|---|---|
| ISC event | 949313 |
| USGS-ANSS | ComCat |
| Local date | 21 February 1996 |
| Local time | 07:51 |
| Magnitude | 7.5 Mw |
| Depth | 25.0 km (16 mi) |
| Epicenter | 9°35′35″S 79°35′13″W / 9.593°S 79.587°W |
| Type | Thrust |
| Max. intensity | MMI IV (Light)[1] |
| Tsunami | Yes |
| Casualties | 12 |
Geology
editThe mechanism inferred from data is a low-angle thrust of the Nazca plate, which is subducting beneath the South American plate.[3] This earthquake occurred in an area where the Peru–Chile subduction zone is relatively quiet.[4]
Tsunami
editThis earthquake was special in that it generated a disproportionally large tsunami. Earthquakes with slow rupture velocities are the most efficient tsunami generators, and the rupture velocity of this earthquake was classified as moderately slow (Newman and Okal, 1996). The tsunami affected the Peruvian coastal area from Pacasmayo, La Libertad to Callao. The straight-line distance between the two areas is about 590 km.[5][6] The greatest runup value of the tsunami was 5.14 m, recorded at the port of Chimbote, located on the north side of Chimbote Bay. Twelve people were killed by the tsunami, all in remote areas, likely due to lack of information. In more populated areas, such as Chimbote, people were aware of the approaching tsunami and were able to evacuate the coast in time.[7] A 60 cm tsunami was recorded in Easter Island and 25 cm in Hilo.
Aftershocks
editThe aftershock pattern of this earthquake ranged from 120 to 180 km off the coast and seemed to parallel the Peru–Chile Trench and the Peruvian coastline.[8] Of the mechanisms of two of the larger aftershocks, one was a shallow thrust, and the other one was normal faulting.[9]
See also
editReferences
edit- ^ ANSS, "M 7.5 – 123 km WSW of Puerto Santa, Peru 1996", Comprehensive Catalog, U.S. Geological Survey
- ^ ISC (27 June 2022), ISC-GEM Global Instrumental Earthquake Catalogue (1900–2009), Version 9.1, International Seismological Centre
- ^ Bourgeois, J.; Petroff, C.; Yeh, H.; Titov, V.; Synolakis, C. E.; Benson, B.; Kuroiwa, J.; Lander, J.; Norabuena, E. (1999). "Geologic Setting, Field Survey and Modeling of the Chimbote, Northern Peru, Tsunami of 21 February 1996". Pure and Applied Geophysics. 154 (3–4): 513–540. Bibcode:1999PApGe.154..513B. doi:10.1007/s000240050242. S2CID 129854200.
- ^ "AGU – American Geophysical Union". AGU.
- ^ "Archived copy" (PDF). Archived from the original (PDF) on 2011-07-26. Retrieved 2010-08-21.
{{cite web}}: CS1 maint: archived copy as title (link) - ^ "Tsunami! – Tsunamis – past and present". ess.washington.edu. Archived from the original on 2022-02-15. Retrieved 2010-08-21.
- ^ "A description of the 1996 tsunami that stuck Chimbote and other costal cities in the north-central region of Peru". Archived from the original on 2010-01-18. Retrieved 2010-08-21.
- ^ Petroff, Catherine; Bourgeois, Jody; Yeh, Harry. "The February 21, 1996 Chimbote Tsunamis in Peru, EERI Special Earthquake Report – May 1996" (PDF). Earthquake Engineering Research Institute. University of Washington.
- ^ Polet, J.; Kanamori, H. (2000). "2000GeoJI.142..684P Page 692". Geophysical Journal International. 142 (3): 684. Bibcode:2000GeoJI.142..684P. doi:10.1046/j.1365-246X.2000.00205.x.
External links
edit- The International Seismological Centre has a bibliography and/or authoritative data for this event.