Oaxaca earthquake



Our paper entitled ‘Seismicity Gap Near Oaxaca, Southern Mexico as a Probable Precursor to a Large Earthquake,’ published in Pure and Applied Geophysics (volume 115, 1977), predicted the large Mexico earthquake that occurred on November 29. I quote in part from the summary: ‘An area of significant seismic quiescence is found near Oaxaca, southern Mexico. The anomalous area may be the site of a future large earthquake as many cases so far reported were… The most probable estimates are: 7½ ± ¼ for the magnitude and ϕ = 16.5° ± 0.5 North, λ = 96.5° ± 0.5 West for the epicenter location. A firm prediction of the occurrence time is not attempted…' According to the Preliminary Determination of Earthquakes from the U.S. Geological Survey, the parameters of the Oaxaca earthquake are Ms = 7.8, ϕ = 16.072°N and λ = 96.487°W.