Folding of lithosphere in the Piemonte-Ligurian ocean

Abstract

Basin development in the Jurassic-Cretaceous Piemonte-Ligurian ocean as inferred from geological data is compared with a model for folding of oceanic lithosphere and subsequent flexuring due to sediment loading. According to the model, basins with a width between 130 and 160 kilometres and a relative depth ranging from 2000 to 2500 metres will develop on oceanic lithosphere with a cooling age between 35 and 55 My. These results are in good agreement with the dimensions of the Internal and External Ligurian basins, calculated from geological reconstructions. Furthermore, the model provides an explanation for the occurrence of slumps and olistostromes observed in the sedimentary record from the Aptian onwards, and for the extensive erosion on the 'Bracco Ridge', a submarine high which separated the Internal from the External Ligurian basin.