A scene from the earliest part of this story can be glimpsed in the sandstones and mudstones of the Camstane Quarry. Some of these rocks illustrate the wave patterns in sand and mud cracks formed by the changing water levels of that time, others may show the weathering associated with exposure to tropical conditions. These sedimentary rocks were pushed aside by the rising volcano.

The volcano itself was able to erupt due to a thinning of the earths crust in the area, allowing the emergence of igneous rock of basaltic composition.