Observations of seismic anisotropy can offer relatively direct constraints on patterns of mantle deformation, but most studies have focused on the upper mantle. While much of the lower mantle is thought to be isotropic, several recent studies have found evidence for anisotropy in the transition zone and uppermost lower mantle (the mid-mantle), particularly in the vicinity of subducting slabs. H...

Sandbox modeling is used to study the deformation of accretionary wedges caused by the subduction of oceanic ridges. The first experiment incorporates a massive ridge within a sand wedge. The wedge thickens and shortens when the forward propagation f the basal decollement ceases. The wedge thickening results in taper change, reactivation of preexisting thrusts, and retreat of the frontal part o...

In this paper we investigate the notion of developing generic aspects in Hyper/J and compare it with other approaches.

the iranian plateau is characterized by diverse tectonic domains, including the continental collisions (e.g. the zagros and alborz mountains) and oceanic plate subduction (e.g. makransubduction zone). to derive a detailed image of the crust–mantle (moho) and lithosphere–asthenosphere (lab) boundaries in some tectonically units of the iranian plateau, we used a large number of s receiver functio...

Subduction zones generate voluminous magma and mediate global element cycling. Fluids are essential to this activity, yet their behavior is perhaps the most poorly understood aspect of the subduction process. Though many volatile components are subducted, H2O is the most abundant, is preferentially fractionated into the fluid phase, and, among terrestrial volatiles, is by far the most effective...

Central Mexico is the site of an enigmatic zone of flat subduction. The general geometry of the subducting slab has been known for some time and is characterized by a horizontal zone bounded on either side by two moderately dipping sections. We systematically evaluate proposed hypotheses for shallow subduction in Mexico based on the spatial and temporal evidence, and we find no simple or obviou...

Thin oceanic crust is formed by decompression melting of the upper mantle at mid-ocean ridges, but the origin of the thick and buoyant continental crust is enigmatic. Juvenile continental crust may form from magmas erupted above intraoceanic subduction zones, where oceanic lithosphere subducts beneath other oceanic lithosphere. However, it is unclear why the subduction of dominantly basaltic oc...

The Upper Cretaceous was a period when reefs and reef mounds were abundant in many parts of the world (JAMES, 1983). One of the most remarkable features of the Cretaceous carbonate platforms in tropical and subtropical environments of the Tethyan realm, was the development of facies complexes dominated by rudists, with or without associated corals (MASSE & PHILIP, 1981; ROSS & SKELTON, 1993; GI...