3D Modelling of Late Quaternary coastal evolution between Albenga and Loano (Western Liguria, Italy)

Abstract

ABSTRACTSeismic lines and sediment cores collected along the shelf between Albenga and Loano (Liguria, NW Italy) allowed an unprecedented reconstruction of the characters and distribution of late Quaternary transgressive littoral deposits. Multiple seismic lines datasets and stratigraphic logs were managed within a single, GIS-based software. This approach allowed the merging, analysis, and interpretation of multimethodological datasets, greatly increasing the understanding of the study area. On seismic reflection lines, the identification of high-amplitude acoustic facies (i.e. coarse-grained deposits), coupled with the analyses of the identified paleo-morphologies, allowed the mapping of (at least) five paleo shorelines along the continental shelf at 30–40 40–60, 60–80, 80–90 and 90–100 m below sea level. Their retrogradiational geometry and terraced distribution likely indicate episodic, stepwise retreats of Late Quaternary coastal system (last 18–11 Ky), compatible with phases of fast sea level rise interspersed by long periods of sea level stillstand.

Keywords

• Marine terraces
• eustatic sea level change
• seismostratigraphy
• Ligurian sea
• Late-Quaternary
• transgressive deposits