Evidence of low Q below Popocatépetl Volcano, and its implication to seismic hazard in Mexico City

• Published in: Geophysical research letters Vol. 27; no. 17; pp. 2753 - 2756
• Main Authors: Shapiro, N. M., Singh, S. K., Iglesias-Mendoza, A., Cruz-Atienza, V. M., Pacheco, J. F.
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01-09-2000; American Geophysical Union
• Subjects: Attenuation; Crystalline rocks; Earth sciences; Earth, ocean, space; Earthquakes; Earthquakes, seismology; Engineering and environment geology. Geothermics; Exact sciences and technology; Igneous and metamorphic rocks petrology, volcanic processes, magmas; Internal geophysics; Melting; Natural hazards: prediction, damages, etc; Rocks; Seismic hazard; Seismic waves; Seismograms; Volcanoes; Mexico State; Mexico; Popocatepetl; Q; amplitude; attenuation; S-waves; magmas; North America; seismograms; frequency; seismic waves; seismic risk
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/1999GL011232

Seismograms recorded in Mexico City reveal that the amplitudes of seismic waves whose wavepaths pass below Popocatépetl, presently an volcano, before reaching the city are diminished by a factor of about one‐third at frequencies greater than 1 Hz as compared to those which do not cross the volcano. The high attenuation of seismic waves below the volcano may be attributed to the presence of magma and partial melting of rocks. Q of shear waves below the volcano is roughly estimated as 60. A consequence of the large attenuation of high‐frequency seismic waves is a decrease in the seismic hazard to low‐rise buildings in Mexico City from intraplate earthquakes whose wavepaths cross the volcano.