Paleoenvironmental conditions and evolution of a muddy turbidite system: an integrated sedimentological and ichnological analysis

Abstract

Recent advances in characterization of turbidite-fans have been achieved through various methodologies, including flume-tank experiments, numerical modeling, seismic analysis, and integrated core and outcrop studies. Ichnology has proven valuable for understanding turbidite systems by providing insights into paleoenvironmental conditions such as oxygen levels, nutrient availability, hydrodynamic energy, and sedimentation rates. Since the 1960s, the Nereites ichnofacies has been linked to flysch deposits, characterized by features such as graphoglyptids, shallow-tier ichnotaxa, complex grazing trails, and diverse, but low density, trace fossils. The aim of this study is to combine ichnological and sedimentological data to improve recognition of subenvironments in turbidite systems. Analysis of five sections in a late Miocene, muddy turbidite system in the Tabernas Basin (SE Spain) shows that: 1) the distal fan lobes are characterized by a high diversity and abundance of predepositional trace fossils linked to the Paleodictyon ichnosubfacies, indicating stable and oligotrophic conditions, and 2) the proximal fan lobes by a low diversity and abundance of postdepositional trace fossils with abundant Ophiomorpha rudis ichnosubfacies in areas close to the feeder channel.