Pupilla muscorum

Vertigo alpestris

 

Tufa

The Inchrory tufa has been described in detail by Preece et al. (1984). The source of the calcium carbonate is a spring within the Dalradian metamorphic limestones that form the eastern flank of Glen Avon at this locality. The tufa has been cut into by the estate road.

The deposit is 6 m thick, with white, brown and grey layers that represent pure tufa and tufa with varying admixtures of organic material, silt and soil. The tufa locally contains charcoal and rock fragments.

Organic remains occur abundantly within the tufa, including molluscs, ostracods, pollen and leaf impressions. The changes in vegetation appear to mirror those in other parts of the Cairngorms, with an early dominance of birch, its replacement by hazel before 7360 14C yr BP and the eventual dominance of Scots Pine. The changes in ground cover impacted on the snail populations, with open-ground species replaced by more shade tolerant molluscs. The mollusc remains include some unusual species. Pupilla muscorum is confined today to coastal dune systems in Scotland and Vertigo alpestris is known from only two other sites in Scotland. The biostratigraphy indicates that the tufa accumulated mainly in the early part of the Holocene.