Farallon slab detachment and deformation of the Magdalena Shelf, southern Baja California

Citation:
Brothers, D, Harding A, Gonzalez-Fernandez A, Holbrook WS, Kent G, Driscoll N, Fletcher J, Lizarralde D, Umhoefer P, Axen G.  2012.  Farallon slab detachment and deformation of the Magdalena Shelf, southern Baja California. Geophysical Research Letters. 39

Date Published:

May

Keywords:

geochronology, gulf-of-california, insights, ma, mexico, motion, pacific plate, sur, tectonic evolution, uplift

Abstract:

Subduction of the Farallon plate beneath northwestern Mexico stalled by similar to 12 Ma when the Pacific-Farallon spreading-ridge approached the subduction zone. Coupling between remnant slab and the overriding North American plate played an important role in the capture of the Baja California (BC) microplate by the Pacific Plate. Active-source seismic reflection and wide-angle seismic refraction profiles across southwestern BC (similar to 24.5 degrees N) are used to image the extent of remnant slab and study its impact on the overriding plate. We infer that the hot, buoyant slab detached similar to 40 km landward of the fossil trench. Isostatic rebound following slab detachment uplifted the margin and exposed the Magdalena Shelf to wave-base erosion. Subsequent cooling, subsidence and transtensional opening along the shelf (starting similar to 8 Ma) starved the fossil trench of terrigenous sediment input. Slab detachment and the resultant rebound of the margin provide a mechanism for rapid uplift and exhumation of forearc subduction complexes. Citation: Brothers, D., A. Harding, A. Gonzalez-Fernandez, W. S. Holbrook, G. Kent, N. Driscoll, J. Fletcher, D. Lizarralde, P. Umhoefer, and G. Axen (2012), Farallon slab detachment and deformation of the Magdalena Shelf, southern Baja California, Geophys. Res. Lett., 39, L09307, doi:10.1029/2011GL050828.

Notes:

n/a

Website

DOI:

10.1029/2011gl050828

Scripps Publication ID:

L09307