Lava Flows: The cliffs of The Storr contain an impressive sequence of around 24 individual lava flows, dating back approximately 1.6 million years. The thickness of these layers varies from 1 meter to over 30 meters.
Laterite Layers: Between the lava layers, thin red layers called laterite are found. These indicate enough time between eruptions for weathering and embryonic soils to develop.
Glacial Influence: During the ice ages, the entire area was repeatedly covered by glacial ice. Glacial ice moved north along the Sound of Raasay, modifying the escarpment on the eastern side of the Trotternish ridge.
Landslides: There have been a series of landslides identified at the Storr. Some are older than the last ice age and have been smoothed by the passage of ice. The more recent ones are jagged and include distinctive formations like the Old Man of Storr and Needle Rock.
The Old Man of Storr is one of the most prominent and recognisable pinnacles. It probably slid away from the main cliff in a single event about 6000 years ago. This formation, along with others like Needle Rock, adds a unique character to the landscape.
Coire Faoin is a large hollow left by the last landslide blocks moving downslope. It's noteworthy that this is not a true glacial corrie but rather a result of landslides.
The geology of the area around the Old Man of Storr reveals a rich and complex history, encompassing volcanic activity, glacial movements, and landslides. These geological processes have shaped an iconic landscape that draws geologists, hikers, and tourists alike. The interaction of lava flows, laterite layers, and glaciation provides a fascinating glimpse into the Earth's dynamic past in this remarkable part of Scotland.