Continental delamination: Insights from laboratory models

• DOI: 10.1029/2011gc003896
• Publication Date: 2012-01-23T08:54:06Z
• Authors: Flora Bajolet; Javier Galeano; Francesca Funiciello; Monica Moroni; Ana‐María Negredo; Claudio Faccenna
• Keywords: Asthenosphere; Delamination; Hotspot (geology)

One of the major issues evolution continental lithospheres is detachment lithospheric mantle that may occur under certain conditions and its impact on surface. In order to investigate dynamics delamination, we performed a parametric study using physically scaled laboratory models. The adopted setup composed three‐layers visco‐elastic body (analog for upper crust, lower mantle) locally thickened/thinned simulate density anomaly (lithospheric root) an adjacent weak zone, lying low viscosity material simulating asthenosphere. results emphasize interplay between flow, deformation, surface topography plate motion during three‐phases process: (1) slow initiation phase controlled by coupling bending associated with contraction dynamic subsidence, (2) lateral propagation delamination alongside extension complex topographic signal buoyancy, while poloidal flow develops around tip delaminating mantle, (3) late characterized counterflow triggers retroward whole model. A semiquantitative allows us determine empirically two parameters: parameter constrains propensity correlates duration first stage, buoyancy characterizing velocity stages therefore cease. Finally, point out similarities differences Sierra Nevada (California, USA) in terms topography, deformation timing delamination.