Marine Notches and Sea-Cave Bioerosional Grooves in Microtidal Areas: Examples from the Tyrrhenian and Ligurian Coasts—Italy

Abstract

ABSTRACT Carobene, L., 2015. Marine notches and sea-cave bioerosional grooves in microtidal areas: Examples from the Tyrrhenian and Ligurian coasts—Italy. Modern and ancient marine notches are present along the cliffs and inside the sea caves of the Gulf of Orosei in Sardinia, the Gulf of Gaeta in Lazio, and in Western Liguria. A morphological quantitative study was undertaken to define the shape and size of notches and their altimetric correlation with the sea-level highstands that created them. The geometrical aspects of the notches along cliffs and the relationship between the mean sea level and the shape of the notch have allowed us to deduce that the main erosion process giving rise to the marine notches is wave action. Conversely, the bioerosive process is the most important cause leading to notch formation inside sea caves. These two types of notch differ in terms of their shape and size and while the former mainly develops above mean sea level, the latter extends below the mean high tide level. Fo...