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.: B21

Site name: Pollagach Burn

Grid reference: [NO 40816 94740]

Locality: Pollagach Burn, c. 4 km ESE of Ballater.

GCR Status: Former

GCR No.: 2666

Type: Natural exposures

Description: Exposures in and around the burn display distinctive mineral assemblages produced by thermal metamorphism when the Ballater Granite Pluton was emplaced into metapelite, calcsilicate- rock and amphibolite of the Tayvallich Subgroup (Argyll Group, Dalradian Supergroup). The minerals wollastonite, diopside, idocrase and grossularite occur in hornfelsed calcsilicate rocks, while andalusite, cordierite and, more rarely, sillimanite and corundum occur in hornfelsed pelitic rocks.

Justification: A good example of the distinct and unusual mineral assemblages that result in contrasting metasedimentary rock types due to thermal metamorphism

References