Introduction to special section: Stress transfer, earthquake triggering, and time‐dependent seismic hazard

Abstract

[1] In this introduction, we review much of the recent work related to stress transfer, earthquake triggering, and time-dependent seismic hazard in order to provide context for the special section on these subjects. Considerable advances have been made in the past decade, and we focus on our understanding of stress transfer at various temporal and spatial scales, review recent studies of the role of fluids in earthquake triggering, describe evidence for the connection between volcanism and earthquake triggering, examine observational evidence for triggering at all scales, and finally discuss the link between earthquake triggering and time-dependent seismic hazard. We conclude by speculating on future areas of research in the next decade.Citation: Steacy, S., J. Gomberg, and M. , Introduction to special section: Stress transfer, earthquake triggering, and time-dependent seismic hazard,

The role of fluid migration and static stress transfer in searching connections between the May 2012 Emilia earthquakes through a fully 3D finite element modeling

“…where Ds is the shear stress change (positive in the fault slip direction), Dr n is the normal stress change (positive for extension), l is the friction coefficient and DP indicates the pore pressure changes, representing the undrained response of the medium on a sufficiently short timescale so that fluid flow cannot occur; at longer timescales the drained response of the medium will modify the pore pressure evolution promoting fluid flow (Steacy et al 2005). A possible undrained pore pressure model is the constant apparent friction model, in which pore pressure is proportional to normal stress changes and Eq.…”

“…where the apparent friction coefficient l 0 is intended to include the effects of pore fluids as well as the material properties of the fault zone (Harris 1998;Cocco and Rice 2002;Steacy et al 2005). Positive or negative variations of the CFF indicate that the stress field is acting to promote or oppose the rupture, respectively.…”

Coulomb static stress changes before and after the 23 October 2011 Van, eastern Turkey, earthquake (<i>M</i><sub>W</sub>= 7.1): implications for the earthquake hazard mitigation

“…where τ and σ n represent the changes in the shear and the normal stresses over the target fault plane, respectively, while µ is the apparent coefficient of the friction (Harris, 1998;Steacy et al, 2005a), which includes the unknown effect of pore fluid pressure and has been postulated to vary in the range 0.2-0.8 (Stein, 1999). The selection of value of µ has been pointed out to be not crucial in affecting the pattern of change in Coulomb failure stress (King et al, 1994;Steacy et al, 2004).…”

“…King et al, 1994;Stein et al, 1997;Harris, 1998;Stein, 1999;Steacy et al, 2004, Steacy et al, 2005a. Because static stress changes caused by an earlier earthquake can promote or delay subsequent earthquakes along nearby faults, earthquake stress changes can be utilised in the interpretation of future seismic hazards or earthquake probabilities (Stein et al, 1997;Nalbant et al, 2002;Utkucu et al, 2003;Parsons, Fig.…”

Dynamics of a seismogenic fault subject to variable strain rate

“…Fault interaction is predicted on theoretical grounds (e.g. Steacy et al, 2005) and is found to be relevant to the long-term behaviour of fault systems (Marzocchi et al, 2003).…”