The end of limestone deposition in the Isle of Man was marked by the explosive eruption of a volcano which formed the basaltic rocks now exposed between Scarlett and Poyllvaaish.
Vents and fissures along which magma flowed to surface can be seen in the area around Scarlett Point.
|Basalt lava and ash are
erupted from a volcano
which form the Scarlett
volcanics at Castletown
|Lava erupted under water
can form pillow-shaped structures,
rather like toothpaste being
squeezed out of a tube
Dykes are fissures in which magma solidifies
before reaching the surface
This photograph shows volcanic rocks at Poyllvaaish