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GEOSITE

ARC VOLCANISM AT FINNY

One of the few places in Ireland where pillow basalts can be seen in both 2D and 3D

Finny’s pillow basalts are the remains of underwater eruptions of lava on the sea floor during a period of arc volcanism. The small holes seen in the pillow basalt, called vesicles, were left behind by gasses escaping the magma.

This 3d model shows one of the famous outcrops with the shape of the pillows clearly standing out. This outcrop was ground down by moving ice during the Quaternary and so displays the pillows in 2d. The 3d aspect is due to the space in between the pillows having weathered faster since the end of the ice age.

This model was gratefully shared by Dr Sadhbh Baxter of NUI Galway.

ES