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

Abstract

Key Points The crustal model proposed by Pedrera et al. (2017) is not supported by the available deep seismic data set The gravity model is built upon inaccurately retrieved residual gravity anomalies and uses inappropriate density values The sequential restoration shows geometric‐structural inconsistencies, mechanical difficulties, and problematic isostatic and kinematic implications

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”

“…We completely agree with Pedreira et al () in that geophysical data do not provide a unique acceptable solution. However, it is well known that this limitation hampers not only potential field modeling but also the rest of geophysical methods, including seismic studies.…”

“… 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 …”

“…We do not concede that any of these main issues disprove our interpretation. Accordingly, we defend our model by addressing, in the same order as their comments, the questions raised by Pedreira et al ().…”

“…The peridotites, essentially paramagnetic, form magnetite during the transformation of olivine and pyroxene into serpentine. As Pedreira et al () highlight, the formation of magnetite is only significant at serpentinization levels higher than 75% (Oufi et al, ). The 2‐D magnetic models reveal magnetic susceptibilities of 0.12 SI in the shallowest part of the high‐density body (Figure ).…”

“…We face this reply as an opportunity to further clarify and update our approach, as well as to discuss the differences with other lithospheric scale models proposed for the North Iberian Margin. Pedreira et al () raise four major concerns about our paper: (i) gravity modeling procedure, (ii) interpretation of the high‐density body inferred from the positive gravity anomalies, (iii) cross‐section restoration, and (iv) geodynamic model. We do not concede that any of these main issues disprove our interpretation.…”