Loch Sguabain
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Condition (NatureScot)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| F1 | Tertiary Igneous | Favourable | — | 2013-01-18 |
Geology & landscape
Rock Type: Basalt, Gabbro
Landscape processes: Volcanic / Igneous
Description
Loch Sguabain Loch Sguabain Site of Special Scientific Interest lies on the north-western slopes of Beinn Fhada above Loch Sguabain in Glen More, on the Isle of Mull. The site is predominantly composed of basalt lava which erupted from a volcano centred on Glen More during the Tertiary period around 60 million years ago. Ovoid-shaped parcels of basalt rock known as “pillows” are scattered throughout the hillside while the site also includes part of the Glen More ring-dyke; a huge sheet-like intrusion comprised of quartz gabbro. Loch Sguabain encompasses the best exposures of pillow lavas in the area. Interesting boundary features of contact can be seen on the site between the basalt rocks and the quartz gabbro of the Glen More ring-dyke. The lavas of Loch Sguabain are important in piecing together the overall geological evolution, of not just the volcano centred on Glen More, but also the volcanoes of Mull as a whole. These volcanoes marked the initiation of the split between Scotland and Greenland with the opening of this particular arm of the Atlantic.