Publication: Reply to Comment by Azor et al. on “On the Rootless Nature of a Devonian Suture in SW Iberia (Ossa-Morena Complex, Variscan Orogen): Geometry and Kinematics of the Azuaga Fault”
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Advisors (or tutors)
American Geophysical Union
Geological mapping, structural data, and analytical modeling by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791 supported that the Central Unit belonged to a rootless Devonian suture zone contiguous to the SW of its exposure and under the upper section of the footwall to the Azuaga Fault. Late exhumation of the Central Unit was via extrusion from the upper-middle crust under inclined triclinic sinistral transpression, which favored upright folding of the suture zone. Azor and coworkers argue that the upright folds that affect the Central Unit are local, despite geological maps and structural data demonstrate they are km-scale and occur all across the Central Unit. Besides ignoring structural data regarding the kinematics of the Azuaga Fault, Azor et al. (2022), https://doi.org/10.1029/2021TC006982 fail to recognize the net upthrown movement of the NE side of the Azuaga Fault, as the Central Unit in that side is juxtaposed against syn-orogenic strata that rest unconformably onto other metamorphic units in the SW side of the fault. Seismic data that image the Central Unit as a NE-dipping rock package is used as an argument against the proposal by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791. However, the section of the Central Unit those data account for, are from a different part of the Central Unit, the real dip of some structures in the seismic image is not properly interpreted, and the model by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791 is compatible with a Central Unit that also dips to the NE. Overall, the model proposed by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791 remains valid.