@misc{10481/64913,
year = {2020},
month = {10},
url = {http://hdl.handle.net/10481/64913},
abstract = {Lithospheric tearing at slab edges is common in scenarios where retreating slabs face
continental margins. Such tearing is often accommodated via subvertical STEP (Subduction-
Transform Edge Propagator) faults that cut across the entire lithosphere and can result in
sharp lateral thermal and rheological variations across the juxtaposed lithospheres. This
setting favors the occurrence of continental delamination, i.e., the detachment between the
crust and the lithosphericmantle. In order to evaluate this hypothesis, we have chosen a wellstudied
natural example recently imaged with unprecedented seismic resolution: the STEP
fault under the central Betic orogen, at the northern edge of the Gibraltar Arc subduction
system (westernmost Mediterranean Sea). The Gibraltar Arc subduction is the result of the
fast westward roll-back of the Alboran slab and it is in its last evolutionary stage, where the
oceanic lithosphere has been fully consumed and the continental lithosphere attached to it
collides with the overriding plate. In this study we investigate bymeans of thermo-mechanical
modeling the conditions for, and consequences of, delamination post-dating slab tearing in
the central Betics.We consider a setup based on a STEP fault separating the orogenic Betic
lithosphere and the adjacent thinned lithosphere of the overriding Alboran domain. Our model
analysis indicates that delamination is very sensitive to the initial thermal and rheological
conditions, transitioning from a stable to a very unstable and rapidly evolving regime. We find
two clearly differentiated regimes according to the time at which the process becomes
unstable: fast and slow delamination. Although the final state reached in both the fast and
slow regimes is similar, the dynamic surface topography evolution is dramatically different.We
suggest that given a weak enough Iberian lower crust the delaminating lithospheric mantle
peels off the crust and adopts a geometry consistent with the imaged southward dipping
Iberian lithosphere in the central Betics. The lack of spatial correspondence between the
highest topography and the thickest crust, as well as the observed pattern of uplift/
subsidence are properly reproduced by a model where relatively fast delamination
(Reference Model) develops after slab tearing.},
organization = {Spanish Government

PGC2018-095154-B-I00
PID2019-109608GB-I00},
organization = {Atraccion Talento senior fellowship - Comunidad Autonoma de Madrid (Spain) 	
2018-T1/AMB/11493},
organization = {National Science Foundation (NSF)

EAR-0949446
EAR-1550901},
publisher = {Frontiers Media SA},
keywords = {Subduction-transform edge propagator fault},
keywords = {Slab tearing},
keywords = {Continental delamination},
keywords = {Topography evolution},
keywords = {Gibraltar Arc subduction system},
title = {Geodynamic Modeling of Edge-Delamination Driven by Subduction-Transform Edge Propagator Faults: The Westernmost Mediterranean Margin (Central Betic Orogen) Case Study},
doi = {10.3389/feart.2020.533392},
author = {Negredo, A. M. and Mancilla Pérez, Flor de Lis and Clemente, C. and Morales Soto, José and Fullea, J.},
}