Decoding the interplay between tidal notch geometry and sea-level
variability during the Last Interglacial (Marine Isotopic Stage 5e) high
stand
Abstract
Relic coastal landforms (fossil corals, cemented intertidal deposits, or
erosive features carved onto rock coasts) serve as sea-level index
points (SLIPs) widely used to reconstruct past sea-level changes.
Traditional SLIP-based sea-level reconstructions face challenges in
capturing continuous sea-level variability and dating erosional
outcrops, such as ubiquitous tidal notches, carved around tidal level on
carbonate cliffs. We propose a novel approach to such challenges by
using a numerical cliff erosion model embedded within a Monte-Carlo
simulation to investigate the most likely sea-level scenarios
responsible for shaping one of the best-preserved tidal notches of the
Last Interglacial age in Sardinia, Italy. Results align with Glacial
Isostatic Adjustment model predictions, indicating that synchronized or
out-of-sync ice-volume shifts in Antarctic and Greenland ice sheets can
reproduce the notch morphology, with sea level confidently peaking at
6m. This new approach yields continuous sea-level insights, bridging
gaps in traditional methods and illuminating past Interglacial sea-level
dynamics.