Carn Gorm

Site of Special Scientific Interest · 57.6293, -4.6101

Condition (NatureScot)

Favourable (1)
UnitFeatureConditionArea (ha)Assessed
F1 Moine Favourable 2014-01-31

Geology & landscape

Landscape processes: Volcanic / Igneous

Description

CARN GORM The Carn Gorm SSSI takes in the summit and eastern slopes of Carn Gorm, lying on the southern ridge of Little Wyvis, above the village of Garve. The rocks of Carn Gorm SSSI are mostly metamorphic rocks (rocks which have been altered under the action of heat and pressure) belonging to the Moine Supergroup (the major rock unit which underlies much of the northern Highlands). The special interest of the SSSI is the presence of a body of igneous rock (formed by the cooling and crystallisation of molten rock or magma) called pegmatite. The pegmatite at this site is largely composed of quartz and feldspar with muscovite mica up to 20 cm across and smaller crystals of garnet. The pegmatite has been dated at 800 million years old, providing some of the first evidence of an orogeny (mountain building event) affecting the rocks of Scotland at that time. Several pieces of evidence for the Knoydartian orogeny have now accumulated, but the Carn Gorm pegmatite remains a key piece in the jigsaw. The Carn Gorm SSSI is considered to be of international importance contributing to current research into Scottish geology.