Remotely triggered subsidence acceleration in Mexico City induced by the September 2017 <i>M</i><sub>w</sub> 7.1 Puebla and the <i>M</i><sub>w</sub> 8.2 Tehuantepec September 2017 earthquakes

Abstract

Mexico City, a large megacity with over 21 million inhabitants, is exposed to several hazards, including land subsidence, earthquakes, and flooding. Hazard assessments for each hazard type is typically treated separately and usually do not include considerations for any relations among the hazards. Our data makes it plausible for an earthquake triggering case that temporarily accelerated the subsidence rate in the metropolitan area as a result of the M w 8.2 Tehuantepec and the M w 7.1 Puebla, September 2017 earthquakes that affected Mexico City. Furthermore, the triggering effect induced rapid slip along previously developed shallow faults associated with subsidence. These results indicate that any future scenario of land subsidence should consider a potential triggering effect by large earthquakes. Similarly, earthquake hazard assessments should also consider potential impact on shallow faulting and fracturing associated with land subsidence.

Over a Century of Sinking in Mexico City: No Hope for Significant Elevation and Storage Capacity Recovery

“…Greater subsidence after this earthquake, also detected by Solano‐Rojas, Cabral‐Cano, et al. (2020), suggests a decrease in near‐surface rigidity due to grain rearrangement allowing sediments to stretch more easily. Similar observations of the effect of strong ground motion on near‐surface rigidity were made by Viens et al.…”

“…Finally, Solano‐Rojas, Cabral‐Cano, et al. (2020), documented subsidence acceleration in the ZMVM following the September 2017 Puebla and Tehuantepec earthquakes. In this work, we combine all the freely available InSAR data (1996–2020) with continuous GPS data (cGPS), leveling data, water data (well locations, pumping rates, water levels through time), sediments thicknesses data (upper aquitard and aquifer), land use data, and population density data, to reconstruct the subsidence history of the past century in the ZMVM and improve our understanding of (1) the processes controlling the land subsidence rates and spatial extent, and (2) how subsidence relates to the socioeconomic landscape.…”