The Internal Subbetic of the Velez Rubio area (SE Spain): Is it tectonically detached or not?

• The Internal Subbetic is not basally detached.
• The Internal Subbetic does not thrust over the Solana Formation.
• The Solana Fm., independently of its Palaeogeographic origin, is above the Subbetic.
• The Internal–External Zones contact here is a dextral strike-slip fault.
• In this area the Internal Zone does not overthrust the External Zone or vice versa.

The sierras of Maria and Maimon form part of the Internal Subbetic in the eastern part of the Betic Cordillera, in contact with the Internal Zone. Previous papers have interpreted the Internal Subbetic as being tectonically detached at its bottom, thrusting the Solana Fm., and moreover thrusting the Internal Zone. Nevertheless, the analysis of the structure of these sierras (with great development of folds), and that of the Sierra del Gigante, indicates that this detachment does not exist and, on the contrary, the structure is clearly rooted. Moreover, the general rectilinear trend of the contact between the Internal and External Zones leads to the interpretation that it in fact corresponds to a dextral transcurrent contact, this contention being supported by the analysis of minor faults. According to the age of the younger sediments involved (the Espejos and Solana Fms.), the main deformation processes occurred from the early Miocene and continued during the middle Miocene, at least in part. The structure and characteristics of the geologic evolution of this area are comparable to that of the Internal Subbetic (Penibetic) in the western part of the cordillera.