A 2006 Colima Rift Earthquakes Series and Its Relationship to the Rivera-Cocos Plate Boundary
Volume 4, Issue 1, February 2015, Pages: 21-30
Received: Dec. 2, 2014;
Accepted: Jan. 5, 2015;
Published: Jan. 19, 2015
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Jaime Yamamoto, Instituto de Geofisica, Universidad Nacional Autónoma de México, México, D.F.
Zenón Jiménez, Instituto de Geofisica, Universidad Nacional Autónoma de México, México, D.F.
From 31 July through 13 August 2006 a series of fourteen earthquakes (M 3.9 to 6.1) occurred in the western end of the Central Mexican Volcanic Belt (CMVB) in a twenty-five days period. The most prominent earthquake (Mw 6.1) occurred on 11 August 2006 at 14:30 UTC (9:30 local time) approximately at 18.37° N, 101.25° W and 81 km depth. The epicenter was less than 40 km from Huetamo, Michoacan a 41,250-inhabitant city and 60 km from the El Infiernillo dam embayment the third largest hydroelectric plant in Mexico. This earthquake was widely felt with minor to moderate reported damage. In Mexico City 250 km away from the epicenter the earthquake produced alarm among the population and several buildings were evacuated. The earthquakes series developed into two activity clusters one centered in the coast and separated about 300 km from a second inland cluster. The initial coastal cluster consisted of a nearly linear activity distribution, which includes shallow-depth earthquakes of reverse and normal faulting mechanisms. The inland cluster shows more compact and deeper hypocenters distribution. Earthquakes first-motion polarities indicate that ruptures occurred as a normal faulting, which is a characteristic of the CMVB earthquakes. The overall trend of earthquakes distribution shows two branches, one, along the El Gordo-Colima graben system direction (~N45°E) nearly perpendicular to the coast and another along an east-west direction parallel to the southern border of the CMVB. Our results indicate that these two branches might constitute part of the continental extension of the Rivera-Cocos plate boundary.
A 2006 Colima Rift Earthquakes Series and Its Relationship to the Rivera-Cocos Plate Boundary, Earth Sciences.
Vol. 4, No. 1,
2015, pp. 21-30.
Bandy, W.L., 1992. Geological and geophysical investigation of the Rivera-Cocos plate boundary: Implications for plate fragmentation. Ph.D. dissertation. Texas A & M Univ. College Station.
Bandy, W., C. Mortera-Gutierrez, J. Urrutia-Fucugauchi, and T. W. Hilde, 1995. The subducted Rivera-Cocos plate boundary: Where is it, what is it, and what is its relationship to the Colima rift?. Geophys. Res. Letters, 22, 3075-3078.
Bourgois, J. and F. Michaud, 1991. Active fragmentation of the North America plate at the Mexican triple junction area of Manzanillo. Geo-Marine Letters, 11, 59-65.
DeMets, C., R. Gordon and S. Stein. 1994. Effect of recent revisions of the geomagnetic reversal time scale on estimates of current plate motions. Geophys. Res. Lett., 21, 2191-2194
DeMets, C. and D.S. Wilson, 1997. Relative motions of the Pacific, Rivera, North American, and Cocos plates since 0.78 Ma. J. Geophys. Res., 102, 2789-2806.
Eissler H. K., and K.C. McNally, 1984. Seismicity and tectonics of the Rivera plate and implications for the 1932 Jalisco, Mexico earthquake. J. Geophys. Res., 89, 4520-4530.
Global Centroid Moment Tensor Project. (2014). http://www.globalcmt.org/CMTsearch.html
Gomberg, J., and P. Bodin, 1994. Triggering of the Ms=5.4 Little Skull Mountain, Nevada earthquake with dynamic strain. Bull. Seism. Soc. Am., 84, 844-853.
Havskov, J., and L..Ottemöller, 1999. Seisan earthquake analysis software. Seism. Res. Letters, 70, 532-534.
Kim, Y., R.W. Clayton, and J.M. Jackson, 2010. Geometry and seismic properties of the subducting Cocos plate in central Mexico. J. Geophys. Res., 115, B06310, doi:10.1029/2009JB006942, 2010.
Nuñez-Cornú, F. J., G. A. Reyes-Dávila, M. Rutz Lopez, E. Trejo Gómez, M. A. Camarena-García, and C. Ariel Ramirez-Vazquez. 2004. The 2003 Armería, México Earthquake (Mw 7.4): Mainshock and early Aftershocks. Seism. Res. Lett., 75, 734-743.
Pardo, M. and G. Suarez. 1993. Steep sbduction geometry of the Rivera Plate beneath the Jalisco Block in western Mexico. Geophysical Research Letters, 20, 2391-2394.
Pardo, M. and G. Suarez, 1995. Shape of the subducted Rivera and Cocos plates in southern Mexico: Seismic and tectonic implications. J. Geophys. Res., 100, 12357-73.
Santoyo, M. A., T. Mikumo and L. Quintanar. 2006. Faulting process and coseismic stress change during the 30 January, 1973, Colima, México, eartquake (Mw=7.6). Geofisica Internacional, 45, 163-178.
Singh, S.K., L. Ponce and S.P. Nishenko. 1985. The great Jalisco, Mexico earthquakes of 1932: Subduction of the Rivera plate. Bull. Seism. Soc. Am.. 75, 1301-1313.
Suarez, G., D. Escobedo, W. Bandy, and F. Pacheco, 1999. The 11 December, 1995 earthquake (Mw=6.4): Implications for the present-day relative motion on the Rivera-Cocos plate. Geophys. Res. Letters, 26, 1957-1960.
Yang, T., S.P. Grand, D. Wilson, M. Guzman-Speziale, J.M. Gomez-Gonzalez, T. Dominguez-Reyes, and J. Ni. 2009. Seismic structure beneath the Rivera subduction zone from finite-frequency seismic tomography. J. Geophys. Res., 114, B01302, doi: 10,1029/2008JB005830.