What Controls the Seismogenic Plate Interface in Subduction Zones?

Ruff, Larry J.; Tichelaar, Bart W.

doi:10.1029/gm096p0105

Cited by 62 publications

(51 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Unfortunately, the location of the fore‐arc mantle corner has not yet been well defined on most margins. Ruff and Tichelaar [] concluded that for the South American subduction zone, the downdip limit of great earthquake rupture approximately coincides with the fore‐arc mantle corner which in turn is approximately at the coast for much of that margin. Heuret et al .…”

Section: Fore‐arc Mantle Corner: Aseismic Serpentinite and Talc On Thmentioning

confidence: 99%

“…There is a common correlation between offshore fore‐arc basins, defined mainly by gravity, and the regions of seismic rupture in past great events globally [ Wells et al ., ; Song and Simons , ]. In a related observation, Ruff and Tichelaar [] found that the landward limit of great earthquake rupture is often beneath the coast. The coast often defines the landward limit of the basins.…”

Section: Geological Associations Of Rupture With Offshore Basinsmentioning

confidence: 99%

“…For hot subduction zones where young lithosphere is being underthrust like Cascadia, there appears to be a maximum temperature limit for seismic behavior [e.g., Hyndman and Wang , ; Oleskevich et al ., ]. For the more common cool subduction zones, aseismic serpentinite and talc downdip in the fore‐arc mantle corner may limit the downdip rupture [e.g., Ruff and Tichelaar , ; Hyndman et al ., ; Oleskevich et al ., ; Peacock and Hyndman , ; Hyndman and Peacock , ]. Ruff and Tichelaar [] noted that the downdip limit is often near the coast.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Downdip landward limit of Cascadia great earthquake rupture

Hyndman

2013

JGR Solid Earth

View full text Add to dashboard Cite

[1] This paper examines the constraints to the downdip landward limit of rupture for the Cascadia great earthquakes off western North America. This limit is a primary control for ground motion hazard at near-coastal cities. The studies also provide information on the physical controls of subduction thrust rupture globally. The constraints are (1) "locked/ transition" zones from geodetic deformation (GPS, repeated leveling, tide gauges); (2) rupture zone from paleoseismic coastal marsh subsidence, "paleogeodesy"; (3) temperature on the thrust for the seismic-aseismic transition; (4) change in thrust seismic reflection character downdip from thin seismic to thick ductile; (5) fore-arc mantle corner aseismic serpentinite and talc overlying the thrust; (6) updip limit of episodic tremor and slip (ETS) slow slip; (7) rupture area associations with shelf-slope basins; (8) depth limit for small events on the thrust; and (9) landward limit of earthquakes on the Nootka transform fault zone. The most reliable constraints for the limit of large rupture displacement, >10 m, are generally just offshore in agreement with thermal control for this hot subduction zone, but well-offshore central Oregon and near the coast of northern Washington. The limit for 1-2 m rupture that can still provide strong shaking is less well estimated 25-50 km farther landward. The fore-arc mantle corner and the updip extent of ETS slow slip are significantly landward from the other constraints. Surprisingly, there is a downdip gap between the best other estimates for the great earthquake rupture zone and the ETS slow slip. In this gap, plate convergence may occur as continuous slow creep.

show abstract

Section: Fore‐arc Mantle Corner: Aseismic Serpentinite and Talc On Thmentioning

confidence: 99%

Section: Geological Associations Of Rupture With Offshore Basinsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Downdip landward limit of Cascadia great earthquake rupture

Hyndman

2013

JGR Solid Earth

View full text Add to dashboard Cite

show abstract

“…Some authors consider that elastic strain can accumulate only between the crystalline basement of the upper plate and the downgoing plate [Byrne et al, 1988;Ruff and Tichelaar, 1996], primarily because the mantle wedge beneath the upper plate is likely to be serpentinized [Hyndman et al, 1997;Oleskevich et al, 1999;Hilairet et al, 2007] and will thus exhibit stable sliding behavior. Some authors consider that elastic strain can accumulate only between the crystalline basement of the upper plate and the downgoing plate [Byrne et al, 1988;Ruff and Tichelaar, 1996], primarily because the mantle wedge beneath the upper plate is likely to be serpentinized [Hyndman et al, 1997;Oleskevich et al, 1999;Hilairet et al, 2007] and will thus exhibit stable sliding behavior.…”

Section: The Seismogenic Zonementioning

confidence: 99%

“…The updip limit is considered by most authors to be related to clay mineral dehydration reactions as high porosity deep-sea sediments are slowly transformed to low-grade metamorphic rocks that exhibit stick-slip behavior Ruff and Tichelaar, 1996;Moore and Saffer, 2001]. These dehydration reactions (illite to smectite and opal to quartz) begin at temperatures of 60-100 o C and continue to about 150 o C [Moore and Saffer, 2001].…”

Section: The Seismogenic Zonementioning

confidence: 99%

How wide is the seismogenic zone of the Lesser Antilles forearc?

Gutscher¹,

Westbrook

Marcaillou³

et al. 2013

Bulletin De La Société Géologique De France

View full text Add to dashboard Cite

The Lesser Antilles subduction zone has produced no recent strong thrust earthquakes, making it difficult to quantify the seismic hazard from such events. The Lesser Antilles arc has a low subduction rate and an accretionary wedge that is very wide at its southern end. To investigate the effect of the wedge on seismogenesis, numerical models of forearc thermal structure were constructed along six transects perpendicular to the arc in order to determine the thermally predicted width of the seismogenic zone. The geometry of each section is constrained by published seismic profiles and crustal models derived from gravity and seismic data and by earthquake hypocenters at depth. A major constraint on the deep part of the model is that mantle temperature beneath the volcanic arc should achieve a temperature of 1,100 o C to generate partial melts. Predicted surface heat flow is compared to the available heat flow observations. Thermal modeling results indicate a systematic southward increase in the width of the seismogenic zone, more than doubling in width from north to south and corresponding to a dramatic southward increase in forearc width (distance from the arc to the deformation front of the accretionary wedge). The minimum width of the seismogenic zone (distance between the intersections of the subduction interface with the 150 o C and 350 o C isotherms) increases from about 80 km, north of 16 o N, to 230 km, at 13 o N. The maximum width (between the 100 o C and 450 o C isotherms) ranges from about 150 km in the north to up to 320 km in the south. This large variation in the width of the seismogenic zone is a consequence of the increasing width of the accretionary wedge to the south, caused by the increased thickness of sediment on the subducting plate. There is good agreement between the thermally predicted seismogenic limits and the sparse distribution of recorded thrust earthquakes, which are observed only in the northern portion of the arc. Possible scenarios for mega-thrust earthquakes are discussed. Depending on the segment length (along-strike) of the rupture plane, the occurrence of an event of magnitude 8-9 cannot be excluded.Résumé. -L'absence de grands séismes récents à mécanismes chevauchants dans la zone de subduction des Petites Antilles rend difficile l'évaluation de l'aléa sismique lié à de tels événements. L'arc des Petites Antilles est caractérisé par une faible vitesse de subduction et par la présence d'un prisme d'accrétion très développé à son extrémité méridionale. Afin d'évaluer les effets de la largeur de ce prisme sur la genèse des séismes, nous avons étudié six sections perpendiculaires à l'arc, du nord au sud de celui-ci, pour déterminer la largeur de la zone sismogène prédite par les modèles thermiques appliqués à chacune de ces coupes. La géométrie de ces dernières est contrainte par les profils sismiques publiés, par les modèles de structure crustale déduits des données gravitaires et sismiques, et enfin par la distribution des hypocentres des séismes. Un contrôle important permettant...

show abstract

The seismic cycle at subduction thrusts: Insights from seismo‐thermo‐mechanical models

et al. 2013

View full text Add to dashboard Cite

[1] The underestimation of the size of recent megathrust earthquakes illustrates our limited understanding of their spatiotemporal occurrence and governing physics. To unravel their relation to associated subduction dynamics and long-term deformation, we developed a 2-D continuum viscoelastoplastic model that uses an Eulerian-Lagrangian finite difference framework with similar on-and off-fault physics. We extend the validation of this numerical tool to a realistic subduction zone setting that resembles Southern Chile. The resulting quasi-periodic pattern of quasi-characteristic M8-M9 megathrust events compares quantitatively with observed recurrence and earthquake source parameters, albeit at very slow coseismic speeds. Without any data fitting, surface displacements agree with GPS data recorded before and during the 2010 M8.8 Maule earthquake, including the presence of a second-order flexural bulge. These surface displacements show cycle-to-cycle variations of slip deficits, which overall accommodate 5% of permanent internal shortening. We find that thermally (and stress) driven creep governs a spontaneous conditionally stable downdip transition zone between temperatures of 350 ı C and 450 ı C. Ruptures initiate above it (and below the forearc Moho), propagate within it, interspersed by small intermittent events, and arrest below it as ductile shearing relaxes stresses. Ruptures typically propagate upward along lithological boundaries and widen as pressures drop. The main thrust is constrained to be weak due to fluid-induced weakening required to sustain regular subduction and to generate events with natural characteristics (fluid pressures of 75-99% of solid pressures). The agreement with a range of seismological, geodetic, and geological observations demonstrates the validity and strength of this physically consistent seismo-thermo-mechanical approach.

show abstract

What Controls the Seismogenic Plate Interface in Subduction Zones?

Cited by 62 publications

References 20 publications

Downdip landward limit of Cascadia great earthquake rupture

Downdip landward limit of Cascadia great earthquake rupture

How wide is the seismogenic zone of the Lesser Antilles forearc?

The seismic cycle at subduction thrusts: Insights from seismo‐thermo‐mechanical models

Contact Info

Product

Resources

About