Recent models support the view that the Pyrenees were formed after the inversion of a previously highly extended continental crust that included exhumed upper mantle rocks. Mantle rocks remain near to the surface after compression and mountain building, covered by the latest Cretaceous to Paleogene sequences. 3‐D lithospheric‐scale gravity inversion demands the presence of a high‐density mantle body placed within the crust in order to justify the observed anomalies. Exhumed mantle, having ~50 km of maximum width, continuously extends beneath the Basque‐Cantabrian Basin and along the northern side of the Pyrenees. The association of this body with rift, postrift, and inversion structural geometries is tested in a balanced cross section across the Basque‐Cantabrian Basin that incorporates a major south‐dipping ramp‐flat‐ramp extensional detachment active between Valanginian and early Cenomanian times. Results indicate that horizontal extension progressed ~48 km at variable strain rates that increased from 1 to ~4 mm/yr in middle Albian times. Low‐strength Triassic Keuper evaporites and mudstones above the basement favor the decoupling of the cover with formation of minibasins, expulsion rollovers, and diapirs. The inversion of the extensional system is accommodated by doubly verging basement thrusts due to the reactivation of the former basin bounding faults in Eocene‐Oligocene times. Total shortening is estimated in ~34 km and produced the partial subduction of the continental lithosphere beneath the two sides of the exhumed mantle. Obtained results help to pinpoint the original architecture of the North Iberian Margin and the evolution of the hyperextended aborted intracontinental basins.

The shape and alignment of silver nanoparticles embedded in a glass matrix is controlled using silicon ion irradiation. Symmetric silver nanoparticles are transformed into anisotropic particles whose larger axis is along the ion beam. Upon irradiation, the surface plasmon resonance of symmetric particles splits into two resonances whose separation depends on the fluence of the ion irradiation. Simulations of the optical absorbance show that the anisotropy is caused by the deformation and alignment of the nanoparticles, and that both properties are controlled with the irradiation fluence. *

The geometrical configuration of Au:Ag nanoparticle heterodimers can be optimized to produce prominent Fano resonance (FR) signals, strong enough to be detectable by standard spectroscopic techniques. The highest intensity of the FR in these bimetallic dimers is reached when the size ratio of the nanoparticles (R Au :R Ag ) is close to 3:1. Moreover, the FR can be induced only by the longitudinal component of the dimer surface plasmon resonance (SPR). Finally, it is found that the sensitivity of the dimer FR signal to the variation in the refractive index of the surrounding medium (n m ) is 2 times larger than that of the associated SPR for the region where n m < 1.5, which opens up the possibility of utilizing the FR band for more efficient optical sensing applications.

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