The Victoria, Mexico, Earthquake of June 9, 1980
Main Article Content
Abstract
The Victoria earthquake of June 9, 1980 (ML = 6.1 ), occurred in the Mexicali Valley near the trace of the Cerro Prieto fault with a focal mechanism consisting of a dextral strike-slip motion on a vertical fault. We present results from an analysis of local data concerning ground surface effects, epicenter locations, and focal mechanisms of the main shock and its aftershock activity. A field reconnaissance showed no clear ground surface displacement related to the main shock. The aftershocks occurred northwest of the main shock epicenter, in a few clusters at or near the northwest end of the Cerro Prieto fault. There was some aftershock activity north of the Cerro Prieto fault tip and towards the southeast end of the Imperial fault. Only a few aftershocks were located near the main shock; they occurred during the first few hours after the main event. The aftershock activity was mainly located between 3 and 8 km in depth, beneath the thick overlying sediments. The average depth of the aftershocks generally decreases to the northwest, away from the main epicenter which is at a depth of about 9 km. Composite focal mechanisms of the aftershocks show a right-lateral strike-slip motion on a vertical plane striking N45°W for the cluster near the main shock epicenter, and normal faulting for the cluster at the northwest end of the Cerro Prieto fault. Two small tightly clustered earthquake swarms occurred a few hours before the main shock.
Article Details

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
References
ALBORES, A., A. REYES, J. N. BRUNE, J. GONZALEZ, L. GARCILAZO and F. SUAREZ, 1980. Seismicity studies in the region of the Cerro Prieto geothermal field. Geothermics, 9, 65-77. DOI: https://doi.org/10.1016/0375-6505(80)90024-3
ANDERSON, J. G., J. PRINCE, J. N. BRUNE and R. S. SIMONS, 1982. Strong Motion Accelerograms. In: The Mexicali Valley Earthquake of June, 1980, edited by J. G. Anderson and R. S. Simons, Newsletter of the Earthquake Engineering Research Institute, 16, 79-83:
ARCHULETA, R. J., 1982. Analysis of near-source, static, and dynamic measurements from the 1979 Imperial Valley earthquake. Bull. Seism. Soc. Am., 72, 1927-1956. DOI: https://doi.org/10.1785/BSSA07206A1927
CHAVEZ, D., J. GONZALEZ, A. REYES, M. MEDINA, C. DUARTE, J. N. BRUNE, F. L. VERNON, R. SIMONS, L. K. HUTTON, P. T. GERMAN y C. E. JOHNSON, 1982. Main shock location and magnitude determination using combined U. S. and Mexican data. In: The Imperial Valley, California, Earthquake of October 15, 1979, Geol. Surv. Prof. Paper, 1254, Washington D. C., 51-54.
COBOS, J. M., 1980. Informe del levantamiento de manantiales y fracturas ocasionadas por el sismo del día 8 de junio de 1980. Technical Report, Coordinadora Ejecutiva de Cerro Prieto, Baja California, Mexico.
DARBY, D., E. NYLAND, F. SUAREZ, D. CHAVEZ, J. GONZALEZ, 1981. Strain and displacement measurements of the June 9, 1980, Victoria, Mexico Earthquake. Geophys. Res. Lett., 8, 549-511. DOI: https://doi.org/10.1029/GL008i006p00549
ELDERS, W. A., R. W. T. MELDAR, P. T. ROBINSON and S. BIEHLER, 1972. Crustal spreading in Southern California. Science, 178, 15-24. DOI: https://doi.org/10.1126/science.178.4056.15
FREZ, J., 1982. Main shock location and focal mechanism. In: The Mexicali Valley Earthquake of June, 1980, edited by J. G. Anderson and R. S. Simons, Newsletter of the Earthquake Engineering Research Institute, 16-3, 74-76.
FREZ, J., V. WONG and D. CHAVEZ, 1983. Interpretación de arribos secundarios en el Valle Mexicali-Imperial, Extended Abstract, Annual Meeting of the Unión Geofísica Mexicana, May 16-20, Mexico City, 1555-1558.
FREZ, J. and J. GONZALEZ, 1987. Sismicidad y mecanismos focales en el Valle Mexicali-Imperial, Geofísica Internacional, 28, 4, 643-691. DOI: https://doi.org/10.22201/igeof.00167169p.1989.28.4.1317
FREZ, J. and J. GONZALEZ, 1990. Crustal structure and seismotectonics of Northern Baja California, Chapter 15. In: The Gulf and Peninsular Province of the Californias, AAPG Memoir 47, edited by J. P. Dauphin and B. R. T. Simoneit, 261-283. DOI: https://doi.org/10.1306/M47542C15
FUIS, S. G., W. D. MOONEY, J. H. HEALEY, G. A. McMECHAN, W. J. LUTTER, 1982. Crustal structure of the Imperial Valley region. In: The Imperial Valley, California, Earthquake of October 15, 1979. U. S. Geol. Surv. Prof. Paper, 1254, Washington, D. C., 25-49.
GONZALEZ, J., J. FREZ and V. WONG, 1983. Mapeo de VpNs en Ia zona sísmica del Valle de Mexicali. In: Memorias VI Congreso Nacional de Ingenieria Sísmica, México, D. F., Soc. Nac. Ing. Sis., 133-149.
JOHNSON, C. E., 1979. Seismotectonics of the Imperial Valley of Southern California, Ph.D. Thesis, California Institute of Technology. Pasadena, California, 353 pp.
JOHNSON, C. E. and D. P. HILL, 1982. Seismicity of the Imperial Valley. In: The Imperial Valley, California, Earthquake of October 15, 1979. Geol. Surv. Prof. Paper, 1254, Washington, D.C., 15-24.
JOHNSON, C. E. and L. K. HUTTON, 1982. Aftershocks and prearthquake seismicity. In: The Imperial Valley, California, Earthquake of October 15, 1979, Geol. Surv. Prof. Paper, 1254, Washington, D. C., 59-76.
KISSLINGER, C. and L. JONES, 1991. Properties of aftershock sequences in Southern California. J. Geophys. Res., 96, 11947-11958. DOI: https://doi.org/10.1029/91JB01200
LEE, W. H. K. and J. C. LAHR, 1975. HYP0-71 (Revised): A computer program for determining hypocenter, magnitude and first motion pattern of local earthquakes. U. S. Geol. Surv. Open-File Rep. 75-311, 114 pp. DOI: https://doi.org/10.3133/ofr75311
LESAGE, P. and J. FREZ, 1990. Source parameters from body waveform data for the Victoria, Mexico, earthquake of June 9, 1980, Geofísica Internacional, 29, 149-169.
LISOWSKI, M. and W. H. PRESCOTT, 1982. Deformation near the epicenter of the 9 June 1980, ML=6.2, Victoria, Mexico, Earthquake. In: Proceeding Fourth Simposium on Cerro Prieto Geothermal Field, Baja California, Mexico, Guadalajara, Jal., Mexico, 285-291.
LOMNITZ, C., F. MOOSER, C. ALLEN, J. N. BRUNE and W. THATCHER, 1970. Seismicity and tectonics of the Northern Gulf of California region, Mexico. Preliminary results. Geofísica Internacional, 10, 37-48. DOI: https://doi.org/10.22201/igeof.00167169p.1970.10.2.1165
MORI, J., 1991. Estimates of velocity structure and source depth using multiple P waves from aftershocks of the 1987 Elmore Ranch and Supertition Hills, California earthquakes. Bull. Seism. Soc. Am., 81, 508-523. DOI: https://doi.org/10.1785/BSSA0810020508
MUNGUIA, L. and J. N. BRUNE, 1984. Local magnitude and sediment amplification observations from earthquakes in the northern Baja California-southern California region. Bull. Seism. Soc. Am., 74, 107-119.
NAKANISHI, I. and H. KANAMORI, 1982. Effects of lateral heterogeneity and source process time on the linear moment tensor inversion of long-period Ray-leigh waves. Bull. Seism. Soc. Am., 72, 2063-2080. DOI: https://doi.org/10.1785/BSSA07206A2063
NICHOLSON, C. and D. W. SIMPONS, 1985. Changes in Vp/Ns with depth: implications for appropiate velocity models, improved earthquake locations, and material properties of the upper crust. Bull. Seism. Soc. Am., 75, 1105-1123.
SIMONS, R. S., 1982. The strong motion record from station Victoria. In: The Mexicali Valley Earthquake of June 9, 1980, edited by J. G. Anderson and R. S. Simons, Newsletter of the Earthquake Engineering Research Institute, 16-3, 83-87.
SUAREZ, F., K. E. SIEH and W. E. ELDERS, 1982. A review of geological effects and damage distribution of the June 9, 1980, Mexicali Valley earthquake. In: The Mexicali Valley Earthquake of June 9, 1980 edited by J.G. Anderson and R. S. Simons, Newsletter of the Earthquake Engineering Research Institute, 16-3, 99-105.
WALD, L. A., S. PERRY-HANSTON and D. D. GIVEN, 1994. The Southern California Network Bulletin: January-December 1983, Open-file Report 94-199, U. S. Geological Survey, California, U.S.A., 16 pp. and apendixes. DOI: https://doi.org/10.3133/ofr94199
WEAVER, C. S. and D. P. HILL, 1978/1979. Earthquake swarms and local crustal spreading along major strike-slip faults in California. Pageoph., 117, 51-64. DOI: https://doi.org/10.1007/978-3-0348-6525-8_4
WONG, V. and J. FREZ, 1982. Aftershock location and fault mechanisms. In: The Mexicali Valley Earthquake of June 9, 1980, edited by J. G. Anderson and R. S. Simons, Newsletter of the Earthquake Engineering Research Institute, 16-3,76-79.
ZELWER, R. and R. B. GRANNELL, 1982. Correlation between precision gravity and subsidence measurements at Cerro Prieto. In: Proceedings of Fourth Symposium on Cerro Prieto Geothermal Field, Baja California, Mexico, Guadalajara, Jal., Mexico, 233-241.