Understanding the geological context of ancient submarine slope failure, mud diapirism and volcanism from the geological record: Olistostromes and Argille Scagliose of the Mediterranean Region

Olistostromes and sedimentary mélanges cropping out in the circum-Mediterranean orogens have been reconsidered as mass-transport deposits. They distribution in the sedimentary record is compared with the modern examples of mass-transport deposits present at the sea floor in different geodynamics settings. A different distribution of mass-transport deposits is still present comparing modern and ancient (fossil) examples, with the former predominating in the passive and extensional margins and the latter apparently characterizing the sedimentary records of ancient contactional margins. This paradox is probably related to the scarce recognition of mass-transport processes and deposits in the present day sea floor of contractional margins.