Barron, H F, Gillespie, M R and Merritt, J W 2011. Geodiversity of the Cairngorms National Park. British Geological Survey Open Report, OR/10/019
A PDF of this report is available from the NORA, the NERC archive
Site no.: B3
Site name: Benty Roads–Bousty Ley
Grid reference:
Locality: Watershed between Boustie Ley and Benty Roads on the north side of Glen Clova.
GCR Status: N/A
GCR No.: N/A
Type: Natural exposure
Description: The site contains the remains of a layer of ancient silcrete (a siliceous soil horizon), now fragmented and forming stratified blocks up to 30 cm across and rarely more than 15 cm thick. The matrix is commonly fine red chert or jasper. The silcrete probably formed in a semi-arid Devonian (c. 400 million year old) landscape, which is here coincident with the current topography.
Justification: Silcrete is rare in the geological record in Scotland, but the site is also important for what it represents - a relict of an ancient land surface. The silcrete's presence indicates that uplift of the crust in this region due to the Caledonian Orogeny had virtually ceased by the time it was deposited, and also that the Caledonian land surface had by that time eroded approximately to the level seen at the present day. The site, along with a few others in north-east Scotland, provides direct evidence that much of the present landscape in the Grampian Highlands may be largely as it was at the end of the Caledonian Orogeny.