A mountain walk up to pretty Corrie Fee uncovers hints of its Arctic glacial past, and great views out of the corrie from the path up to the waterfall
Corrie Fee National Nature Reserve (NNR) sits on the shoulder of the Cairngorms plateau at the head of Glen Clova in Angus, eastern Scotland. Corrie Fee is one of the best examples of a glacial corrie in the British Isles, with its magnificent natural amphitheatre of crags. It has long been famous for its rare, lime loving arctic-alpine plants, which we now know have survived a remarkable 11,000 years in this wild place.
Corrie Fee’s Dalradian geology is complex. There are outcrops of amphibolite (a dark rock, often with elongate, shiny crystals) on the west side of Corrie Sharroch and the south of Corrie Fee. These formed from volcanic rocks, mostly lava flows that appear to have erupted underwater and are rich in calcium. Cooled ‘sill’ intrusions of magma of a similar composition also occur both adjacent to the band of amphibolite, and in smaller patches elsewhere in the reserve. A band of crystalline limestone, and limestone interlayered with psammite, runs roughly north-south across the western slopes of Corrie Fee. With the exception of the hard sill intrusions, the calcium-rich, ‘basic’ rocks of the reserve are quite crumbly and erode readily to form strongly calcareous soils. This calcium-rich soil is able to support the lime-loving plants that make the reserve such a botanically interesting place.
The corrie itself was excavated by moving glacier ice during repeated glaciations over the last 2.5 million years. The last glacier flowed out from a plateau ice cap that covered Mayar and down the corrie into the woods of Glen Doll about 12,000 years ago. This last glacier left distinct moraine ridges, called flutes; these were formed from sediments deformed under the immense water pressure under the fast-flowing outlet glacier. These fluted moraines can be glimpsed from the path amongst the trees in the woods below Corrie Fee. Up the sides of the corrie are fragments of lateral moraines, which have been partly buried by rock falls and debris flows from the crags and gullies. This type of moraine is formed when rock debris is pushed out to the sides of a glacier as it moves downslope.
After the glacier retreated it left deep lochans in between the moraine mounds. Over the last 11,000 years these have infilled, first with fine sands and then meters of peat. Pollen from trees, shrubs and plants collected in the growing layers of peat over many summers. Scientists have cored the peat and have identified the different types of plants that used to grow here. From this we know that there were once areas of willow and juniper scrub, and patches of birch and hazel woodland with a few pine, oak, elm and alder. Alpine plants have been living here continuously since the last ice age. Many of these are now found only on ledges and gullies that grazing deer cannot reach.
Corrie Fee and its landforms are best viewed from the lovely Fee waterfalls path, which winds its way up the back of the corrie high up onto the plateau. Wet weather fills this burn quickly creating a spectacular series of waterfalls down the corrie back wall. From time to time, extremely wet weather also causes debris flows to flow like wet concrete down from the gullies into the corrie, forming large debris cones.
Text contributed by Shona Smith and Ness Kirkbride
Find out more
H.J.B. Berks 1993 Coire Fee in The Geological Conservation Review: Quaternary of Scotland Chapter 9: Eastern Grampian Mountains
Corrie Fee National Nature Reserve: https://www.nature.scot/enjoying-outdoors/scotlands-national-nature-reserves/corrie-fee-national-nature-reserve
Walk description and information https://www.walkhighlands.co.uk/angus/corrie-fee.shtml
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