- Copyright © 1988, by the Seismological Society of America
The coda Q method has been applied to a set of earthquakes recorded by the short-period vertical component of the seismograph station OXM in southern Mexico. A frequency independent Q0 value of 489 for the Lg phase has been found for southern Mexico. This value is similar to the values found for central Rocky Mountains, and higher than those obtained for the Western United States.
Assuming that Pg, Pn, Sg, and Sn phases behave as wave trains, attenuation coefficients have been found for periods close to 1 sec. The attenuation coefficient values for the Pg, Sn, and Sg phases are almost equal to that of the Lg phase. The Pn wave shows a slightly higher γ value than the corresponding Lg wave. This could be due to scattered Pn data. This study indicates that the 1 Hz Lg attenuation in southern Mexico is about three times lower than in California.