Geological Timeline - Durness
Oldest to most recent (Ma = million years)
- 2700 Ma - Molten bodies cool to form granite-like rocks within the lower levels of the Earth's crust. High pressure and temperature conditions at depth then recrystallise the rock which results in the formation of bands to create (Lewisian) gneiss.
- 1600 Ma - A 'Laxfordian' tectonic event deforms the Lewisian Gneiss further with intrusion of pegmatite veins / sheets.
- 1000 Ma - Deposition of the Moine sequence several tens of kilometres to the east (upon a basement of Lewisian-like gneiss)
- 600 Ma - Opening of the Iapetus Ocean which eventually creates a flat, extensive marine platform through erosion.
- 520 Ma - Quartzite laid down on erosion surface as quartz-rich, shallow-marine sandstones during the Cambrian period.
- 510 Ma - Area located within a tropical to semi-arid latitude within the Southern Hemisphere. Deposition of Durness Limestone as carbonate production takes over during late Cambrian and Ordovician times.
- 430 Ma - Closure of the Iapetus Ocean and start of Caledonian mountain building, resulting in deformation of the Moine rocks to form schist and the formation of the Moine Thrust.
- 430 Ma - The Moine Thrust carries the Moine Schist and part of it's Lewisian-type basement westwards over younger foreland rocks, creating a 'Moine Thrust Zone' of deformation below the main thrust plane. Some Lewisian Gneiss is heavily stretched by shear forces to form 'Oystershell Rock'.
- 250 Ma - Tectonic extension & faulting during Permo-Triassic times which creates the Durness (half) graben. The area would have been desert-like highlands during these times.
- 2>Ma - Repeated phases of glaciation and cave formation during the Quaternary period. Thick covering of glacial till and peat.