1 / 25

Himalayan foreland

Himalayan foreland. Foreland basins. www.geos.ed.ac.uk/homes/mnaylor/Links.html. Huge potential for erosion in modifying stresses is nowhere better illustrated than Himalaya; however critical taper theory only approximates outer edge of system. Collisional mountain belt. Pinchout point.

sileas
Download Presentation

Himalayan foreland

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Himalayanforeland Foreland basins www.geos.ed.ac.uk/homes/mnaylor/Links.html

  2. Huge potential for erosion in modifying stresses is nowhere better illustrated than Himalaya; however critical taper theory only approximates outer edge of system

  3. Collisional mountain belt

  4. Pinchout point Forebulge Accommodation space (Hole) Flexure of beams Semi-infinite Infinite

  5. Amount of flexure Flexural parameter Flexural rigidity M0 Flexure of the lithosphere

  6. Basin types – Ocean-arc boundary

  7. Basin types – Orogenic belts

  8. Taiwan

  9. dxtopo/dt Vthrust Topographic load (Ltopo) Vonlap Vplate Subsurface load (Lsub) Vplate is key determinant of foreland basin metrics f(Ltopo + Lsub + f(Vplate) Vthrust = f(dxtopo/dt) Vonlap = dxtopo/dt + f(Vplate) Mountain belt/foreland basin coupling Initial recognition of dependence of foreland basin on thrust geometry and growth (Beaumont, 1981; Jordan, 1981) Sea-level Subsidence = ,Te) + f(Vplate)

  10. Early analyses System simulated by a tapered wedge overthrusting an elastic beam with surface redistribution by diffusion(Flemings & Jordan 1989; Sinclair et al., 1991)

  11. Retro-peripheral foreland basin Pro-peripheral foreland basin Geometry Chronostratigraphy Steady-state time time growth Onset of orogenesis distance distance Onset of orogenesis Onset of orogenesis Steady-state Steady-state growth growth Tectonic subsidence depth depth Naylor & Sinclair, submitted to Basin Research

  12. Taiwan

  13. Taiwan

  14. time time Steady-state growth Onset of orogenesis distance distance Chronostratigraphy

  15. The Pyrenees Topography Topographic cross-section Aquitaine Basin Ebro Basin N S Geodynamic model

  16. Thrust propagation consumes foreland basin (D. Garcia-Castellanoset al, 1997)

  17. Flexure Foreland basin Thrusting Flexural Basin Concept Price 1973 Pinchout point

  18. Pro-peripheral basin (Over subducting slab lots of thrusting)

  19. - Ebro Basin (Pro-peripheral) from Verges et al., 1995. - Aquitaine Basin (Retro-peripheral) from Desegaulx and Brunet 1990. time time orogenesis distance distance Ebro Basin Aquitaine Basin (Pro) (Retro) Upper Senonian Oligocene 0 50km Lower Cretaceous Upper Eocene Foreland basin succession basement Lower Eocene (sandst.) Lower Eocene (carbonates) Palaeocene

  20. Foreland Basin Summary • Foreland basins are elongate basins located at ocean-continent and continent-continent collision zones • They form in flexural depressions • The flexural depression can be modelled using an elastic beam • The growth of topography loads the beam • The basin is bound by the thrust front and the stable craton • The advection of the basin fill towards the mountain belt creates accommodation space • The basin is consumed as the thrust front propagates out

  21. www.geos.ed.ac.uk/homes/mnaylor/Links.html

More Related