Article history: Subduction of the Indian lit Received 8 August 2007 Received in revised form 7 July 2008 Accepted 10 July 2008 Available online 20 July 2008 Editor: C.P. Jaupart

The formation of new subduction zones is a key element plate tectonics and the Wilson cycle, many different controlling mechanisms have been proposed to initiate subduction. Here, we provide brief overview known scenarios initiation in intra-oceanic ocean-continent tectonic settings. Intra-oceanic most commonly associated with mechanical heterogeneities within oceanic lithosphere, such as pre-e...

[1] Subduction zones alter the upper plate in a variety of ways, including metasomatism via slab-derived fluids and accretion of exotic terranes. These processes should produce distinctive seismic signatures, as seismic velocities are sensitive to compositional variations. A new method is developed to estimates depths to interfaces and Poisson’s ratio (Vp/Vs ratio) for dipping layered structure...

It is widely accepted that water-rich serpentinite domains are commonly present in the mantle above shallow subducting slabs and play key roles in controlling the geochemical cycling and physical properties of subduction zones. Thermal and petrological models show the dominant serpentine mineral is antigorite. However, there is no good consensus on the amount, distribution and alignment of this...

A new analytic model is presented for the thermal structure of subduction zones. It applies to the deeper regions of a subduction zone, where the overriding mantle is no longer rigid but flows parallel to the slab surface. The model captures the development of one thermal boundary layer out into the mantle wedge, and another into the subducting slab. By combining this model with the analytic mo...

Double seismic zones are two-layered distributions of intermediate-depth earthquakes that provide insight into the thermomechanical state of subducting slabs. We present new precise hypocenters of intermediate-depth earthquakes in the Tonga subduction zone obtained using data from local island-based, ocean-bottom, and global seismographs. The results show a downdip compressional upper plane and...

We investigate upper plate stressing during the earthquake cycle in a subduction segment, using three-dimensional (3-D) elastic models to address the effects of strongly heterogeneous coupling along strike of the interplate interface. We show how heterogeneity controls the locations and mechanisms of seismicity in the upper plate. Oblique subduction segments, two from the Aleutians (Andreanof I...

The fault geometry, depth, and slip distribution of the Kurile earthquake of Oct. 4, 1994 are estimated using seismic waveforms, aftershock distribution, geodetic measurements, and tsunami waveforms. Previous large earthquakes in the Kurile arc had typical underthrusting focal mechanisms due to the local subduction. Seismic wave inversions of the 1994 event indicate a thrust type mechanism with...

Probabilistic seismic hazard maps are widely used for engineering design, land use planning, and disaster mitigation etc. This study conducted a review of readily available information on tectonic setting, geology, and seismicity, and the attenuation of peak ground acceleration (PGA) of Taiwan for completing the revised probabilistic seismic hazard maps by the state-of-the-art probabilistic sei...

[1] Changes of plate motion may have induced subduction initiation (SI), but the tectonic history of SI is different from one subduction zone to another. Izu-Bonin-Mariana (IBM) SI, accompanied by strong backarc spreading and voluminous eruption of Boninites, contrasts with the Aleutians which shows neither. Using finite element models, we explore visco-elasto-plastic parameters and driving bou...