| Abstract | Since the discovery of extensive earthquake triggering occurring in response to the 1992 Mw (moment magnitude)
7.3 Landers earthquake, it is now well established that seismic waves from earthquakes can trigger
other earthquakes, tremor, slow slip, and pore pressure changes. Our contention is that earthquake triggering
is one manifestation of a more widespread elastic disturbance that reveals information about Earth’s stress
state. Earth’s stress state is central to our understanding of both natural and anthropogenic-induced crustal
processes. We show that seismic waves from distant earthquakes may perturb stresses and frictional properties
on faults and elastic moduli of the crust in cascading fashion. Transient dynamic stresses place crustal material
into a metastable state during which the material recovers through a process termed slow dynamics. This observation
of widespread, dynamically induced elastic perturbation, including systematic migration of offshore
seismicity, strain transients, and velocity transients, presents a new characterization of Earth’s elastic system
that will advance our understanding of plate tectonics, seismicity, and seismic hazards. |
