Torridonian

Geological map of the Hebridean Terrane showing distribution of Torridonian sediments

The Torridonian is the informal name given to a sequence of Mesoproterozoic to Neoproterozoic sedimentary rocks that outcrop in a strip along the northwestern coast of Scotland and some parts of the Inner Hebrides from the Isle of Mull in the southwest to Cape Wrath in the northeast. They lie unconformably on the Archaean to Paleoproterozoic basement rocks of the Lewisian complex and unconformably beneath the Cambrian to Lower Ordovician rocks of the Ardvreck Group.