Long Duration of Ground Motion in the Paradigmatic Valley of Mexico

Abstract

Built-up on top of ancient lake deposits, Mexico City experiences some of the largest seismic site effects worldwide. Besides the extreme amplification of seismic waves, duration of intense ground motion from large subduction earthquakes exceeds three minutes in the lake-bed zone of the basin, where hundreds of buildings collapsed or were seriously damaged during the magnitude 8.0 Michoacán earthquake in 1985. Different mechanisms contribute to the long lasting motions, such as the regional dispersion and multiple-scattering of the incoming wavefield from the coast, more than 300 km away the city. By means of high performance computational modeling we show that, despite the highly dissipative basin deposits, seismic energy can propagate long distances in the deep structure of the valley, promoting also a large elongation of motion. Our simulations reveal that the seismic response of the basin is dominated by surface-waves overtones, and that this mechanism increases the duration of ground motion by more than 170% and 290% of the incoming wavefield duration at 0.5 and 0.3 Hz, respectively, which are two frequencies with the largest observed amplification. This conclusion contradicts what has been previously stated from observational and modeling investigations, where the basin itself has been discarded as a preponderant factor promoting long and devastating shaking in Mexico City.

Basin Resonance and Seismic Hazard in Jakarta, Indonesia

“…Earthquake-induced resonance is a phenomenon that occurs in deep sedimentary basins, as seen in Mexico City (Cruz-Atienza et al [1], Rial et al [2]) and Kathmandu (Galetzka et al [3]) due to the 1985 Michoacán and 2015 Nepal earthquakes, respectively. Greater Jakarta (including Jakarta as well as the adjacent cities of Bekasi, Bogor, Depok, Tangerang and Tangerang Selatan) is the world's 4th largest urban agglomeration with a population of 28.9 million (Brinkhoff [4]), and has experienced destructive earthquakes in 1699 (Nata & Witsen [5]), 1780 (Albini et al [6]) and 1834 (Musson [7]).…”

The Significance of Long‐Period Ground Motion at Regional to Teleseismic Distances From the 610‐km Deep Mw 8.3 Sea of Okhotsk Earthquake of 24 May 2013

“…Such large and lengthy shaking of tall buildings reminds us of long‐period (2–10 s) ground motions amplified by thick sedimentary basins during large earthquakes (e.g., Chen et al, ; Cruz‐Atienza et al, ; Denolle et al, ; Furumura & Hayakawa, ; Koketsu et al, ). The distant felt reports for the 2013 Sea of Okhotsk earthquake are concentrated in population centers, commonly situated on thick sedimentary basins, at epicentral distances of 5,000–8,000 km (Figure b).…”

Nucleation and Kinematic Rupture of the 2017 Mw 8.2 Tehuantepec Earthquake

“…This earthquake is ranked as the strongest intraplate event ever recorded in Mexico with a moment magnitude of M 8.2, and the third largest intraplate event known globally (Wiens et al, 1998;Yue et al, 2012). Eleven days after the event, another intraslab earthquake ruptured near Mexico City (e.g., Melgar, Pérez-Campos, et al, 2018) causing widespread damage in Mexico's capital, where nearly~300 people died and~45 building collapsed due to basin amplification (Çelebi et al, 2018;Cruz-Atienza et al, 2016;Galvis et al, 2017;Sahakian et al, 2018;Singh et al, 2018). The Mexican earthquake early warning system delivered an alert to major cities in central Mexico within a few seconds after the earthquake, sirens in Mexico City went off 92 s before the arrival of the surface waves which arrived near midnight 7 September 2017 local time (Suárez et al, 2018).…”

“…The Mexican earthquake early warning system delivered an alert to major cities in central Mexico within a few seconds after the earthquake, sirens in Mexico City went off 92 s before the arrival of the surface waves which arrived near midnight 7 September 2017 local time (Suárez et al, 2018). Eleven days after the event, another intraslab earthquake ruptured near Mexico City (e.g., Melgar, Pérez-Campos, et al, 2018) causing widespread damage in Mexico's capital, where nearly~300 people died and~45 building collapsed due to basin amplification (Çelebi et al, 2018;Cruz-Atienza et al, 2016;Galvis et al, 2017;Sahakian et al, 2018;Singh et al, 2018). This event coincidentally occurred on the 32nd anniversary of the great 1985 M 8.1 Michoacan earthquake, only 2 hr after the annual national earthquake drill.…”