Geodynamic implications derived from Numidian-like distal turbidites deposited along the Internal–External Domain Boundary of the Betic Cordillera (S Spain)

New data reveal Early Burdigalian ‘Numidian-like lithofacies’ in successions of the internal (southernmost) part of the South Iberian Margin (SIM) and the south-western margin of the Mesomediterranean Microplate (MM). The well-known Numidian Formation was deposited in the external (Massylian) sub-domain of the Maghrebian Flysch Basin (a south-western branch of the Tethys Ocean). The anomalous occurrence of ‘Numidian-like lithofacies’ is induced by the particular Early Miocene palaeogeographical and geodynamic complexity of the sector. This consisted of a ‘triple point’ with a dextral transform fault between the SIM and the MM-Maghrebian Flysch Basin system. In this framework, the ageing of Iberian reliefs and the MM collapse, coupled with an African Margin upbulging, and a shortening of the Maghrebian Flysch Basin (both related to the subduction), could have resulted in the arrival of the Numidian depositional system from so far away.

This research was supported by Urbino University ‘Carlo Bo’ grant (responsible F. Guerrera), Spanish CICYT Research Projects CGL2009-09249, CGL2011-30153-CO2-02, and CGL2012-32169, Portuguese FCT Research Project PTDC⁄CLI⁄72585⁄2006, Research Groups and projects of the Generalitat Valenciana from Alicante University (CTMA-IGA), and Research Group 146 of the Junta de Andalucía. The first author is also grateful to the Portuguese FCT ‘Ciência 2008’ Programme Contract C2008-IST⁄CVRM.1.