Lower Bashkirian conodonts from the Nevado-Filábride complex (Betic Cordilleras, Spain): tectonic and palaeogeographic implications
Abstract
The Nevado-Filábride Complex is a fragment of the Variscan-Alleghanian belt that was recycled during the Alpine Orogeny. This makes difficult the interpretation of its pre-Mesozoic tectonic provenance and of general palaeogeographic meaning. However, it is a key terrain to understand the geometry and the evolution of the Betic Orogen. Here, we report for the first time the presence of lower Bashkirian conodonts (Declinognathodus bernesgae, D. inaequalis, D. praenoduliferous and Idioprioniodus sp. elements) in black limestones at the base of the Aulago Fm in the lowest tectonic unit of the Nevado-Filábride Complex (Bodurria Unit). The samples come from graphite-rich thin fine detrital marble horizons between fine-grained low-grade slates with some rippled quartzite horizons. These metasediments were deposited in moderately deep and calm anoxic marine environments, only sporadically affected by bottom currents. This finding supports a correlation of the Nevado-Filábride terrains to the Cantabrian and the West Asturian Leonese tectono-palaeogeographic realms of the Variscan Iberian Massif. This correlation indicates that, below the Betic deformational front, the Iberian palaeogeographic realms continued towards the SE to connect with the continental margin related to the westernmost Palaeotethys.
- Publication:
-
EGU General Assembly Conference Abstracts
- Pub Date:
- April 2017
- Bibcode:
- 2017EGUGA..1913925R