acrylic on canvas,
66cm x 45cm,
Iain White 1984,
Meall nan Cra’ and Meall an Fheadain (Lewisian), the more northerly peaks of the quartzite ridge which rises to Spionnaidh (Spionnich) and Grann Stacach (Cranstackie) to the south, are seen here across the Kyle of Durness. Along the eastern shore of the Kyle the Durness Group, or Durness Limestone outcrops. It represents an accumulation of hundreds of metres of calcium-magnesium carbonate called dolomite. The majority of this group of strata are bio-chemical precipitates deposited at a time when the input of mineral detritus which had formed the earlier quartzites and grits in this part of the Cambrian sea had largely stopped.
There are several different groups of strata within the Durness Group. The oldest is the dark grey Ghrudaidh Formation, a few tens of metres thick. These carbonates are overlain by the paler Eilean Dubh Formation. Both units contain rare body fossils but in general the alteration of these sediments into dolomite after deposition has destroyed most of the macro fossil content.
Between the ‘limestone and the quartzite ridge the middle distance consists of inliers of Lewisian gneiss