This large block, about 4 m³ in size, was expelled by phreatomagmatic explosions accompanying the formation of Petrel Crater maar. The eruption, which formed a low relief 300-m-wide crater in about 1905 CE, marked the most recent recorded activity on Penguin Island. The growth rate of the reddish-orange lichens mantling the upper part of the ejected block was used to estimate the date of the eruption.

Photo by Oscar González-Ferrán (University of Chile).

This image is made available under the Creative Commons BY-NC 4.0 license terms.

Keywords: ejecta | block

Penguin Island