Quaternary Mass-Transport Deposits on the North-Eastern Alboran Seamounts (SW Mediterranean Sea)

Abstract

The Quaternary stratigraphic architecture of seamounts and surrounding deposits in the eastern Alboran Sea reveals at least 53 stacked MTDs in the Pollux Bank, Sabinar Bank (Sabinar Platform and Western Sabinar), Maimonides Ridge, and Adra Ridge. These MTDs are grouped into two types based on their size: small-scale MTDs (length <5 km and thickness <18 ms) and large-scale MTDs (length >5 km and thickness >18 ms). The study of these deposits has allowed us to define a close relationship between size (thickness-length) and source area gradients. The frequency of MTD events has varied between 40 and 373 kyr throughout the Quaternary (1.8 Ma to present). Correlation between individual MTDs is difficult but could be done for at least one local MTD event between Sabinar Platform and Western Sabinar (Sabinar Bank); in addition, one regional MTD event has been recognized around all of the studied seamounts. These failure events could have been triggered by tectonically controlled seismicity at both regional and local scale.