Subduction of oceanic lithosphere occurs through two modes: subducting plate motion and trench migration. Using a global subduction zone data set and three-dimensional numerical subduction models, we show that slab width (W) controls these modes and the partitioning of subduction between them. Subducting plate velocity scales with W(2/3), whereas trench velocity scales with 1/W. These findings ...

[1] To investigate the possible physical mechanisms of recently observed aseismic slip events in the Cascadia, Japan and Mexico subduction zones, we apply a Dieterich-Ruina rate and state friction law to a three dimensional model of a shallow subduction fault. That is loaded by imposed steady plate slip rate far downdip along the thrust interface. Friction properties are temperature and hence d...

Recent observations of an association between forearc basins and slip during subduction thrust earthquakes suggest a link between processes controlling upper plate structure and seismic coupling on the subduction-zone thrust fault. We present a mechanism for the formation of these basins where sedimentation occurs on landward-dipping segments of the subduction wedge, which itself is actively gr...

Geophysical data from the offshore Cascadia forearc reveal many Quaternary upper-plate faults and folds. Most active structures are within the accretionary wedge, but significant deformation is also found on the continental shelf. Several faults and synclines project into adjacent coastal bays where deformation of Pleistocene marine terraces is reported. Rapidly buried marsh deposits and drowne...

baft ophiolitic – mélange belt is a part of the ophiolite melange belt of central iran whose genesis is considered as an environment related to tethys subduction at upper cretaceous. major part of intrusive masses of baft ophiolitic – melange form gabbros with the inequigranular texture fine to coarse and pegmatitic, plagiogranites also with inequigranular general texture have been developed wi...

Atarbolana makranensis sp. n. is described from the intertidal zone of Makran along the Iranian coast of the Gulf of Oman. Atarbolana makranensis sp. n. can be recognized by the presence of a tuft of long setae on the antennal flagellum of males, elongate pleotelson with 12 robust marginal setae, pleotelson with narrowly rounded apex extending well beyond the uropodal endopod, uropodal endopod ...

The October, 1995 Mw 8.0 Jalisco subduction earthquake has provided a thorough geodetic observation of the coseismic subduction process. An 11 station regional GPS network located directly onshore of the rupture demonstrates consistent vertical subsidence verified by tide gauge data and southwest-directed extension, with measured displacements reaching I meter. Unusually shallow and non-uniform...

The Laramide orogeny is the Late Cretaceous to Palaeocene (80^55 Ma) orogenic event that gave rise to the Rocky Mountain fold and thrust belt in Canada, the Laramide block uplifts in the USA, and the Sierra Madre Oriental fold and thrust belt in Mexico. The leading model for driving Laramide orogenesis in the USA is flat-slab subduction, whereby stress coupling of a subhorizontal oceanic slab t...

[1] Dynamic pore pressure changes in the overriding wedge above a shallow-dipping plate interface significantly affect the rupture dynamics of shallow subduction zone earthquakes and their tsunamigenesis. For a wedge on the verge of Coulomb failure everywhere including the basal fault, the dynamic pore pressure increase due to up-dip rupture propagation leads to widespread yielding within the w...