subduction

Low-Frequency Earthquakes Downdip of Deep Slow Slip Beneath the North Island of New Zealand

We report the first catalog of low-frequency earthquakes in the Hikurangi subduction zone, located beneath the Kaimanawa Range of the North Island at 50 km depth, downdip of regularly recurring (every 4–5 years) deep M7 slow slip events. To …

Along-strike segmentation of seismic tremor and its relationship with the hydraulic structure of the subduction fault zone

Along the strike of subduction zones, tectonic tremor episodicity is segmented on a geologic scale. Here, we study how this segmentation reflects large-scale variations of the structure and conditions of the fault interface where tremor is generated. …

Imaging the Spatiotemporal Evolution of Plate Coupling With Interferometric Radar (InSAR) in the Hikurangi Subduction Zone

The coupling at the interface between tectonic plates is a key geophysical parameter to capture the frictional locking across plate boundaries and provides a means to estimate where tectonic strain is accumulating through time. Here, we use both …

What makes low-frequency earthquakes low frequency

Low-frequency earthquakes, atypical seismic events distinct from regular earthquakes, occur downdip of the seismogenic megathrust where an aseismic rheology dominates the subduction plate boundary. Well situated to provide clues on the slip regime of …

Subdaily slow fault slip dynamics captured by low-frequency earthquakes

Geodetic positioning is the geophysical record of reference for slow slip events, but typical daily solutions limit studies of the evolution of slow slip to its long-term dynamics. Accompanying seismic low-frequency earthquakes located precisely in …

Interseismic coupling along the Mexican subduction zone seen by InSAR and GNSS

Crust and upper-mantle seismic anisotropy variations from the coast to inland in central and Southern Mexico (2): Correlations with Tectonic Tremor

Seismic anisotropy in the flat slab region of Mexico is compared with tectonic tremor activity. The anisotropy is observed in three separate horizontal layers using a novel technique with receiver functions. Those layers are identified as the …

Moment-duration scaling of low-frequency earthquakes in Guerrero, Mexico

Low-frequency earthquakes (LFEs) are detected within tremor, as small, repetitive, impulsive low-frequency (1--8 Hz) signals. While the mechanism causing this depletion of the high-frequency content of their signal is still debated, this feature may …

Statistical evidence of a seismic quiescence before the M$_w$8.1 Iquique earthquake, Chile

The 2014 Iquique seismic crisis in Chile, culminating with a $M_w$ 8.1 earthquake on 1 April, highlights a complex unlocking of the Northern Chilean subduction that has been considered a seismic gap since 1877. During the year preceding this event, …

The transient and intermittent nature of slow slip

To first order, faults are locked while stress builds up to a devastating earthquake. However, we know that faults also slip slowly. After decades of geophysical observation, slow slip is now recognized as part of a continuum of transient deformation …