Himalayan tectonics explained by extrusion of a low-viscosity crustal channel coupled to focused surface denudation

Recent interpretations of Himalayan–Tibetan tectonics have proposed that channel flow in the middle to lower crust can explain outward growth of the Tibetan plateau, and that ductile extrusion of high-grade metamorphic rocks between coeval normal- and thrust-sense shear zones can explain exhumation of the Greater Himalayan sequence. Here we use coupled thermal–mechanical numerical models to show that these two processes—channel flow and ductile extrusion—may be dynamically linked through the effects of surface denudation focused at the edge of a plateau that is underlain by low-viscosity material. Our models provide an internally self-consistent explanation for many observed features of the Himalayan–Tibetan system.

[1]  J. Borel,et al.  Thermodynamical Size Effect in Small Particles of Silver , 1972, November 16.

[2]  G. Whitesides,et al.  Molecular self-assembly and nanochemistry: a chemical strategy for the synthesis of nanostructures. , 1991, Science.

[3]  N. Harris,et al.  Tectonothermal evolution of the High Himalayan Crystalline Sequence, Langtang Valley, northern Nepal , 1992 .

[4]  B. Burchfiel,et al.  The South Tibetan Detachment System, Himalayan Orogen: Extension Contemporaneous With and Parallel to Shortening in a Collisional Mountain Belt , 1992 .

[5]  L. Derry,et al.  Evolution of the Himalaya since Miocene time: isotopic and sedimentological evidence from the Bengal Fan , 1993, Geological Society, London, Special Publications.

[6]  Sean D. Willett,et al.  Mechanical model for the tectonics of doubly vergent compressional orogens , 1993 .

[7]  J. Tullis,et al.  A flow law for dislocation creep of quartz aggregates determined with the molten salt cell , 1995 .

[8]  A. Macfarlane.  An evaluation of the inverted metamorphic gradient at Langtang National Park, Central Nepal Himalaya , 1995 .

[9]  L. Royden.  Coupling and decoupling of crust and mantle in convergent orogens: Implications for strain partitioning in the crust , 1996 .

[10]  R. Parrish,et al.  Isotopic constraints on the age and provenance of the Lesser and Greater Himalayan sequences, Nepalese Himalaya , 1996 .

[11]  K. Hodges,et al.  Tectonic evolution of the central Annapurna Range, Nepalese Himalayas , 1996 .

[12]  C. Davidson,et al.  Ductile extrusion of the Higher Himalayan Crystalline in Bhutan: evidence from quartz microfabrics , 1996 .

[13]  Handong Tan,et al.  Partially Molten Middle Crust Beneath Southern Tibet: Synthesis of Project INDEPTH Results , 1996, Science.

[14]  Christopher Harrison,et al.  Block copolymer lithography: Periodic arrays of ~1011 holes in 1 square centimeter , 1997 .

[15]  T. Harrison,et al.  Express Letter A Late Miocene-Pliocene origin for the Central Himalayan inverted metamorphism , 1997 .

[16]  K. Shull,et al.  Metal-Polymer Interactions in a Polymer/Metal Nanocomposite , 1997 .

[17]  K. Hodges,et al.  Shisha Pangma Leucogranite, South Tibetan Himalaya: Field Relations, Geochemistry, Age, Origin, and Emplacement , 1997, The Journal of Geology.

[18]  Thomas J. Owens,et al.  Implications of crustal property variations for models of Tibetan plateau evolution , 1997, nature.

[19]  D. Kohlstedt,et al.  High‐temperature deformation of dry diabase with application to tectonics on Venus , 1998 .

[20]  Larry D. Brown,et al.  Crustal structure of the Himalayan orogen at ∼90° east longitude from Project INDEPTH deep reflection profiles , 1998 .

[21]  W. Kidd,et al.  Yadong cross structure and South Tibetan Detachment in the east central Himalaya (89°–90°E) , 1998 .

[22]  Heinrich M. Jaeger,et al.  Silicon nitride membrane substrates for the investigation of local structure in polymer thin films , 1998 .

[23]  Lenz,et al.  Liquid morphologies on structured surfaces: from microchannels to microchips , 1999, Science.

[24]  A. Balazs.  Interactions of nanoscopic particles with phase-separating polymeric mixtures , 1999 .

[25]  Control of Coulomb blockade characteristics with dot size and density in planar metallic multiple tunnel junctions , 1999 .

[26]  M. Sandiford,et al.  High‐precision geothermobarometry across the High Himalayan metamorphic sequence, Langtang Valley, Nepal , 2000 .

[27]  G. Gehrels,et al.  Tectonic implications of U-Pb zircon ages of the himalayan orogenic belt in nepal , 2000, Science.

[28]  Jinglin Wan,et al.  Evolution of the Kangmar Dome, southern Tibet: Structural, petrologic, and thermochronologic constraints , 2000 .

[29]  R L Sandstrom,et al.  Spin-dependent tunneling in self-assembled cobalt-nanocrystal superlattices. , 2000, Science.

[30]  Leigh H. Royden,et al.  Topographic ooze: Building the eastern margin of Tibet by lower crustal flow , 2000 .

[31]  C. Vieu,et al.  Temperature behavior of multiple tunnel junction devices based on disordered dot arrays , 2000 .

[32]  D. Huse,et al.  Mechanisms of ordering in striped patterns. , 2000, Science.

[33]  K. Hodges.  Tectonics of the Himalaya and southern Tibet from two perspectives , 2000 .

[34]  B. Grasemann,et al.  Himalayan inverted metamorphism and syn-convergence extension as a consequence of a general shear extrusion , 2001, Geological Magazine.

[35]  A. Mayes,et al.  Block copolymer thin films : Physics and applications , 2001 .

[36]  B. Burchfiel,et al.  Large-scale crustal deformation of the Tibetan Plateau , 2001 .

[37]  B. N. Upreti,et al.  Stratigraphy, structure, and tectonic evolution of the Himalayan fold‐thrust belt in western Nepal , 2001 .

[38]  Michael P. Bishop,et al.  Crustal reworking at Nanga Parbat, Pakistan: Metamorphic consequences of thermal‐mechanical coupling facilitated by erosion , 2001 .

[39]  B. Lebeau,et al.  Design and Properties of Hybrid Organic–Inorganic Nanocomposites for Photonics , 2001 .

[40]  M. Bickle,et al.  Constraints on the exhumation and erosion of the High Himalayan Slab, NW India, from foreland basin deposits , 2002 .

[41]  Randall R. Parrish,et al.  Himalayan metamorphic sequence as an orogenic channel: Insight from Bhutan , 2002 .

[42]  G. Clarke,et al.  Metamorphic processes: a celebration of the career contribution of Ron Vernon , 2002 .

[43]  W A Lopes,et al.  Nonequilibrium self-assembly of metals on diblock copolymer templates. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[44]  C. Beaumont,et al.  Interaction of metamorphism, deformation and exhumation in large convergent orogens , 2002 .