A new age model for the middle Eocene deep-marine Ainsa Basin, Spanish Pyrenees

作者：Scotchman J I^*; Bown P; Pickering K T; BouDagher Fadel M; Bayliss N J; Robinson S A

来源：Earth-Science Reviews, 2015, 144: 10-22.

DOI：10.1016/j.earscirev.2014.11.006

• Ainsa Basin
• Hecho Group
• Biostratigraphy
• Nannofossil
• Larger benthic foraminifera
• Eocene

The middle Eocene Ainsa Basin, Spanish Pyrenees, compries similar to 4 km of deep-marine sedimentary rocks belonging to the Hecho Group. Despite extensive study of these exemplary deep-marine clastic successions, there has been no comprehensive chronostratigraphic framework that provides primary ages for the submarine fan and related deposits. Here, we present a new composite basin stratigraphy based upon biostratigraphic analyses of the Upper Hecho Group submarine-fan and interfan deposits. Calcareous nannofossil data suggest that deposition of the Gerbe through to Guaso systems occurred during biozones NP14-16 (42.6 and 48.9 Ma based on our age model). Additional biostratigraphic ages from the Lower Hecho Group suggest that the entire Hecho Group no older than biozone NP13 (similar to 51 Ma). The improved chronostratigraphic control enables correlations between submarine canyons and submarine-fans of the Ainsa and Jaca basins to be assessed. Our new age model provides a means of comparison of stratigraphic events with regional sections allowing a better understanding of the lateral and temporal evolution of these depositional systems from source-to-sink.

• 出版日期2015-5