Dominant fault plane orientations of intermediate-depth earthquakes beneath South America

A global survey of stress orientations in subducting slabs as revealed by intermediate-depth earthquakes

S U M M A R Y We examine a variety of mechanisms that have been proposed as contributors to the stress fields expressed as intermediate-depth seismicity in subducting slabs. To this end, we study principal stress orientations for a global data set of 1900 intermediate-depth focal solutions, determining the patterns of events characterized primarily by downdip compression, downdip tension, or ne...

Resolving Fault Plane Ambiguity for Small Earthquakes

Depth profile of the fractal dimension associated to earthquakes distribution in the NW South America

We have analyzed a seismological catalog of approximated 103.000 earthquakes with 0.1 ≤ mL ≤ 6.8 and depths ranging between 0 and 200 km. This catalog was estimated by the National Seismological Network of Colombia with 17 stations in the period 1993-2013. Data allowed calculate the spatial variations (dependence with depth) of the seismic regime (fractal dimension of the earthquakes distributi...

Intermediate-Depth Earthquakes in a Region of Continental Convergence: South Island, New Zealand

It is rare to find earthquakes with depths greater than 30 km in continent–continent collision zones because the mantle lithosphere is usually too hot to enable brittle failure. However, a handful of small, intermediate-depth earthquakes (30–97 km) have been recorded in the continental collision region in central South Island, New Zealand. The earthquakes are not associated with subduction but ...

Dehydration-driven stress transfer triggers intermediate-depth earthquakes

Intermediate-depth earthquakes (30-300 km) have been extensively documented within subducting oceanic slabs, but their mechanics remains enigmatic. Here we decipher the mechanism of these earthquakes by performing deformation experiments on dehydrating serpentinized peridotites (synthetic antigorite-olivine aggregates, minerals representative of subduction zones lithologies) at upper mantle con...