Drumadoon - Tormore
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Condition (NatureScot)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| F1 | Permian - Triassic (red beds) | Favourable | — | 2009-02-20 |
| F2 | Tertiary Igneous | Favourable | — | 2015-03-17 |
Climate exposure
This is about exposure to a nationwide pressure this habitat type carries — not a verdict on this site's own management.
Coastal habitats are exposed to sea-level rise and storm erosion. Where hard sea defences sit behind them, there's nowhere landward to retreat to — a squeeze that keeps compressing the habitat no matter how well it's managed.
Geology & landscape
Geological Feature: Cave / Cavern, Raised Beach · Geological Period: Paleogene, Triassic · Rock Type: Mudstone
Landscape processes: Coastal, Karst, Volcanic / Igneous
Description
DRUMADOON - TORMORE The coast and adjoining raised beach cliffs from Drumadoon to Tormore, less than 1km north west of Blackwaterfoot on the west coast of Arran, provide an unrivalled opportunity to study an exceptionally varied range of the minor intrusions characteristic of the Palaeogene Volcanic Province, which formed around 60 million years ago. The site includes the celebrated dykes and sheets of volcanic glass (“Judd’s Dykes”) south of Tormore, associated composite dykes whose members are basaltic and granitic in composition, intrusions of flow banded, devitrified volcanic glass at Cleiteadh nan Sgarbh and the thick composite sill forming Drumadoon, which shows contamination and mixing of granitic and basaltic magmas. In addition the Auchenhew Mudstone Formation of Anisian-Ladinian age (Triassic) is well represented by the coastal exposures between King’s Cave and Drumadoon. The sequence contains water-lain red mudstones, siltstones and thin sandstones with sedimentary structures such as symmetrical and asymmetrical ripples, wavy, lenticular and flaser bedding, and also halite pseudomorphs. These rocks usually show rock units which coarsen upwards, and frequently evidence of bimodal (two-directional) palaeocurrents. These features, and the occurrence of trace fossils (Siphonites and Cylindricum) indicate a marine inter-tidal environment and make this an important site in the elucidation of environments and palaeogeography in Triassic times, which occurred around 240 million years ago.