Academic
Publications
Evolutionary model of the Himalaya–Tibet system: geopoem

Evolutionary model of the Himalaya–Tibet system: geopoem,10.1016/S0012-821X(99)00277-0,Earth and Planetary Science Letters,Alexander I. Chemenda,Jean-

Evolutionary model of the Himalaya–Tibet system: geopoem   (Citations: 47)
BibTex | RIS | RefWorks Download
A two-dimensional thermo-mechanical laboratory modelling of continental subduction was performed. The subducting continental lithosphere includes a strong brittle upper crust, a weak ductile lower crust, and a strong upper mantle. The lithosphere is underlain by a low viscosity asthenosphere. Subduction is produced by a piston (push force) and the pull force from the mantle lithospheric layer, which is denser than the asthenosphere. The lithospheric layers are composed of material whose strength is sensitive to and inversely proportional to temperature. Throughout the experiment the model surface was maintained under relatively low temperature and the model base at higher temperature. The subduction rate satisfied the Péclet criterion. Modelling confirms that the continental crust can be deeply subducted and shows that slab break-off, delamination and tectonic underplating are fundamental events with drastic consequences on the subsequent evolution of the convergent system. Combining these results with previous, purely mechanical modelling, we elaborate a new evolutionary model for the Himalaya–Tibet convergent system. The principal successive stages are: (1) subduction of the Indian continental lithosphere to 200–250 km depth following subduction of the Tethys oceanic lithosphere; (2) failure and rapid buoyancy-driven uplift of the subducted continental crust from ca. 100 km depth to some depth that varies along the mountain belt (20–30 km on average); (3) break-off of the Indian subducted lithospheric mantle with the attached oceanic lithosphere; (4) subduction/underplating of the Indian lithosphere under Asia over a few to several hundred kilometers; (5) delamination, roll-back, and break-off of the Indian lithospheric mantle; (6) failure of the Indian crust in front of the mountain belt (formation of the main central thrust) and underthrusting of the next portion of Indian lithosphere beneath Tibet for a few hundred kilometers. At the beginning of stage (6), the crustal slice corresponding to the Crystalline Himalayas undergoes ‘erosion-activated’ uplift and exhumation.
Journal: Earth and Planetary Science Letters - EARTH PLANET SCI LETT , vol. 174, no. 3, pp. 397-409, 2000
Cumulative Annual
View Publication
The following links allow you to view full publications. These links are maintained by other sources not affiliated with Microsoft Academic Search.
    • ...Many studies have correlated observations of temporal and/or spatial changes in magmatism, metamorphism, and horizontal or vertical crustal motion and stress states with the occurrence of slab detachment, based on petrologic and geochemical studies (Astis et al., 2006; Calmus et al., 2003; Ferrari, 2004), gravity modeling (Sperner et al., 2004) and laboratory experiments (Chemenda et al., 2000; Faccenna et al., 2006)...

    Erin R. Andrewset al. Rheologic controls on the dynamics of slab detachment

    • ...After HP–LT metamorphism estimated at c. 55 Ma (De Sigoyer et al. 2000), and probably because of buoyancy forces (Chemenda et al. 1995, 2000), the Tso Morari nappe migrated Table 1. Synthesis of previous geochronological data related to the units studied in this work...
    • ...During early Eocene time, the Tso Morari slab was sheared off the subducted Indian crust and transported by buoyancy forces (Chemenda et al. 1995, 2000) toward the Earth’s surface at a vertical exhumation rate of at least 5 mm a� 1 (De Sigoyer et al. 2000)...

    M. Schlupet al. Exhumation history of eastern Ladakh revealed by 40Ar/39Ar and fission...

    • ...The stresses supporting the strong non-isostatic signatures in the Himalayan region are created by the underthrusting of the Indian crust beneath Asia, replacing the Asian lithosphere, which is sinking into the mantle (Chemenda et al. 2000)...

    Ludìk Vecseyet al. Multiresolution tectonic features over the Earth inferred from a wavel...

    • ...Ultimately, the subduction of buoyant felsic crust could not be sustained and mechanical failure occurred (Chemenda et al., 2000)...
    • ...Even though alternative scenarios exist (Henk et al., 2000), a slab break-off model is favoured here (Davies & von Blanckenburg, 1995; Chemenda et al., 2000; Atherton & Ghani, 2002) – one that would trigger overturn of a hot crustal root and rapid exhumation of the Gföhl Assemblage, including granulites, accompanied by mantle peridotites, eclogites and pyroxenites (Brueckner & Medaris, 2000; O’Brien, 2000; Medaris et al., ...
    • ...Based on Brueckner & Medaris (2000), Chemenda et al. (2000), O’Brien (2000) and Medaris et al. (2005)...

    V. Holub. The causal link between HP-HT metamorphism and ultrapotassic magmatism...

Sort by: