The Age Relationship of the Granophyre and Basalt of Orval, Isle of Rhum

On Orval, in the Isle of Rhum, Tertiary plateau lavas directly overlie the granophyre of the ring-complex. Judd considered that the Orval basalts rest unconformably upon an old land surface cut in the granophyre; but on the supposed existence of veining and metamorphism later workers, in particular Geikie and Harker, concluded that the granophyre had intruded the volcanic pile. The author's re-examination of the Orval rocks supports Judd's early interpretation.