sentences:  A later northwest-southeast aligned swarm of dykes of Palaeogene age intrude these rocks whilst several geological faults run generally NW-SE.There are limited outcrops of sedimentary rock in the east, these being of the Eileans Sandstone assigned to the Clyde Sandstone Formation of the Carboniferous age Inverclyde Group.A raised beach is developed along the lower-lying east coast of the island on which have accumulated marine deposits and blown sand.