Reply to Comment by Pedreira et al. on “Reconstruction of the Exhumed Mantle Across the North Iberian Margin by Crustal‐Scale 3‐D Gravity Inversion and Geological Cross Section”

Abstract

Key Points A continuous high‐density body is regarded as exhumed mantle rocks beneath the Basque‐Cantabrian Basin extending along the Northern Pyrenees Pedreira et al. () doubts our 3‐D gravity model, the view of the high‐density body as exhumed mantle, and the proposed geodynamic model We defend point by point our model that offers important keys to understand the extension and inversion of the North Iberian Margin

Reactivation of a hyperextended rift system: The Basque–Cantabrian Pyrenees case

“…The SW-NE-oriented Central section runs from the Duero foreland basin in the south to the offshore Landes High in the north (Figure 3). The interpretation of this section generated long-lasting debates regarding the rift architecture, the nature of high magnetic and gravimetric anomalies flooring the Bilbao Anticlinorium, and the reactivation of the area (e.g., Pedreira et al, 2018Pedreira et al, , 2021Pedrera et al, 2017Pedrera et al, , 2018Quintana et al, 2015; for discussion see previous section).…”

Basement and cover architecture in the Central Pyrenees constrained by gravity data

“…Goleby et al 1989;Ayala et al 2019). Since Torné et al (1989), several works including potential field modelling have been published trying to image the deep structure of the Pyrenees down to the lithospheric mantle (e.g., Adam 1993;Casas et al 1997;Ledo et al 2000;Vacher and Souriau 2001;Jammes et al 2010;Pedrera et al 2017Pedrera et al , 2018Chevrot et al 2018;Wehr et al 2018;García-Senz et al 2019) or focusing on the upper crustal structures covering more specific zones in the southern Pyrenees (e.g. Santolaria et al 2016;Calvín et al 2018).…”

Regional Crustal Imaging by Inversion of Multimode Rayleigh Wave Dispersion Curves Measured From Seismic Noise: Application to the Basque‐Cantabrian Zone (N Spain)

“…The blue lines show the initial models derived from the magnetic susceptibilities reported by Pedrera et al. (2018) (“magnetic” model, left, see Table S1 in the supporting information) and from the gravity model of García‐Senz et al. (2019) (“gravity” model, right, see Table S2 in the supporting information) and their associated dispersion curves.…”

“…The S-wave velocities of the exhumed mantle rocks can be estimated either from their magnetic properties, which are dependent upon their degree of serpentinization (e.g., Maffione et al, 2014;Oufi et al, 2002), or from their densities (e.g., Christensen, 1996Christensen, , 2004Carlson & Miller, 2003). However, there are some inconsistences between the magnetic properties and the densities employed by the authors of the exhumed mantle model (see the comment by Pedreira et al, 2018), so we derived two 1D shear velocity models to use as starting models: one from the magnetic model by (Pedrera et al, 2017(Pedrera et al, , 2018 S1 and S2 in the supporting information). We then used these models as initial solutions in a nonlinear inversion of the phase velocities compiled at node 1575, which is located above the mantle uplift zone proposed by these authors.…”

“…Comparison of the "exhumed mantle" models with the observed phase velocities (black dots) at node 1575 (Eastern Basque-Cantabrian Zone). The blue lines show the initial models derived from the magnetic susceptibilities reported byPedrera et al (2018) ("magnetic" model, left, see…”