Grennan Bay
Also within
Condition (NatureScot)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| F1 | Caledonian Structures of the Southern Uplands | Favourable | — | 2014-07-17 |
Geology & landscape
Rock Type: Shale
Description
GRENNAN BAY Grennan Bay lies approximately 12km southeast of Portpatrick on the west side of The Rhins. The site provides outstanding exposures of a Moffat Shale inlier, of great importance in understanding the geological history and structure of the Southern Uplands. Almost continuous exposures illustrate a transitional contact of Moffat Shale with greywackes of the Central Belt as well as across both margins of an inlier. The Moffat Shale inliers have played a central role in the debate over the structure and history of the Southern Uplands for more than a century. Recent interpretations have placed great emphasis on the role of faults (crustal dislocations) in modifying the structure of the inliers. These faults are now thought to have a greater cumulative effect on the geological structure of the region than the folds responsible for the inliers. This re-interpretation reflects new theories of global mountain building processes (plate tectonics) which have led to a fresh insight into the geological evolution of the Southern Uplands. Grennan Bay provides clear exposures of both folds and faults and demonstrates the relationship between these structures as well as related minor structures. Although not fully studied, this site offers great potential for future research into this key aspect of the geology of the Southern Uplands.