We develop a single-station tremor spectrum template detection method that we applied to continuous seismic data recorded by the Mexican National Seismological Service broadband stations. This allows for an unprecedented long-term analysis of tectonic tremor in Mexico over multiple slow slip events (SSEs). We only detect tremor that are within previously discovered tremor regions, thereby extending the catalog in time but not space. The resulting catalog demonstrates the strong correlation of bursts of tremor activity and aseismic slip over multiple slow slip cycles. The M~7 long-term SSEs in the states of Guerrero and Oaxaca are associated with the longest sequences of tremor bursts. Each of these tremor bursts are made up of a series of smaller bursts. In between the large M7 SSEs, there are shorter-duration, isolated tremor bursts. In Guerrero, these shorter bursts were found to accompany M~6 short-term SSEs. The occurrence of these short-duration tremor bursts in Oaxaca demonstrates that small short-term SSEs occur in both major slow slip regions in Mexico. The discrete range of tremor burst sizes and rates suggests that slow slip events in the Mexican subduction zone are organized into characteristic moment and moment rates. The catalog also reveals other aseismic transients, such as postseismic slip in Oaxaca after the 16 February 2018 M w 7.2 Pinotepa Nacional earthquake. We highlight that such long-term catalogs are a useful tool together with geodetic observations to monitor slow slip activity that potentially plays a role in the subduction megathrust cycle.

Either the triggering of large earthquakes on a fault hosting aseismic slip or the triggering of slow slip events (SSE) by passing seismic waves involve seismological questions with important hazard implications. Just a few observations plausibly suggest that such interactions actually happen in nature. In this study we show that three recent devastating earthquakes in Mexico are likely related to SSEs, describing a cascade of events interacting with each other on a regional scale via quasi-static and/or dynamic perturbations across the states of Guerrero and Oaxaca. Such interaction seems to be conditioned by the transient memory of Earth materials subject to the “traumatic” stress produced by seismic waves of the great 2017 (Mw8.2) Tehuantepec earthquake, which strongly disturbed the SSE cycles over a 650 km long segment of the subduction plate interface. Our results imply that seismic hazard in large populated areas is a short-term evolving function of seismotectonic processes that are often observable.

Separating different sources of signal in Interferometric Synthetic Aperture Radar (InSAR) studies over large areas is challenging, especially between the long‐wavelength changes of atmospheric conditions and tectonic deformations, both correlated to elevation. In this study, we focus on the 2017–2018 slow slip event (SSE) in the Guerrero state (Mexico) where (1) the permanent GPS network has a low spatial density (less than 30 stations in an area of 300  × 300 km) with uneven distribution; (2) the tropospheric phase delays can be as high as 20 cm of apparent ground displacements, with a complex temporal evolution; (3) the tested global weather models fail to correct interferograms with enough accuracy (with residual tropospheric signal higher than the tectonic signal); and (4) the surface displacement caused by the seismic cycle shows complex interactions between seismic sequences and aseismic events. To extract the SSE signal from Sentinel‐1 InSAR time series, we test two different approaches. The first (parametric method) consists of a least squares linear inversion, imposing a functional form for each deformation or atmospheric component. The second uses independent component analysis of the InSAR time series. We obtain time series maps of surface displacements along the radar line of sight associated with the SSE and validate these results with a comparison to GPS. Combining those two approaches, we propose a method to separate atmospheric delays and tectonic deformation on time series data not corrected from atmospheric delays. From the extracted ground deformation maps, we propose a first‐order slip inversion model at the subduction interface during this SSE.

Triggering of large earthquakes on a fault that hosts aseismic slip or, conversely, triggering of slow slip events (SSE) by passing seismic waves involves seismological questions with major hazard implications. Just a few observations plausibly suggest that such interactions actually happen in nature. In this study we show that three recent devastating earthquakes in Mexico are likely related to SSEs, describing a cascade of events interacting with each other on a regional scale via quasi-static and/or dynamic perturbations. Such interaction seems to be conditioned by the transient memory of Earth materials subject to the “traumatic” stressing produced by the seismic waves of the great Mw8.2 Tehuantepec earthquake, which strongly disturbed the aseismic beating over a 650 km long segment of the subduction plate interface. Our results imply that seismic hazard in large populated areas is a short-term evolving function of seismotectonic processes that are often observable.

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