No demonstrated link between sea-level and eruption history at Santorini

Abstract

Previous studies have suggested a link between rates of sea-level variation and eruptions globally [McGuire et al., 1997], with Satow and coauthors [2021] presenting the first detailed comparison between sea-level change and eruptive history for a single island-volcano. They use robust, high-resolution ages for volcanic deposits at Santorini, combined with a 2D numerical model to correlate sea-level reduction with volcanism. Lowering sea level reduces overburden pressure and is predicted to increase tensile stress in the magma chamber roof, leading to diking and eventually eruption. Having independently reproduced their results, we disagree with the numerical model for three main reasons: (1) predictions of stress distribution and magnitudes caused by sea level change are solely dependent on the size and boundary conditions of the 2D model; (2) minor changes to the model dimensions, dimensionality (2D to 3D), and/or addition of a mantle analogue, removes correlation between sea level and eruptions; and (3) crustal loading conditions at the volcano absent from the model are more significant than sea level change.