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Patterned Ground Tinto Hill
Tinto Hill is composed entirely of felsite, a fine grained but not glassy volcanic rock. It is high in silica or felsic, typically consisting of the minerals quartz, plagioclase feldspar and alkali feldspar. Felsite is usually called the extrusive equivalent of granite. It is very prone to frost shattering and felsite hills often produce active scree slopes. A maritime periglacial climate prevails in Scotland above about 600 metres resulting in sorted patterned ground on loose scree material.
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Editor's Notes
- #3 Tinto Hill is composed entirely of felsite, a fine grained but not glassy volcanic rock. It is high in silica or felsic, typically consisting of the minerals quartz, plagioclase feldspar and alkali feldspar. Felsite is usually called the extrusive equivalent of granite. As can be seen here, it is very prone to frost shattering and felsite hills often produce active scree slopes.
- #4 Location map.
- #5 During the summer months the pattern of stripes is degraded by the tracks of animals and hill walkers. Low oblique light is the best for picking out the stripes. If you turn the image into black and white in the stamp filter in photoshop....
- #6 ....the stripes show up very clearly.
- #9 The fine grained stripes contain a black soil which aids colonisation by wind blown grass seeds. Grazing by sheep probably helps to keep the scree slopes clear.
- #10 A maritime periglacial climate prevails in Scotland above about 600 metres resulting in sorted patterned ground on loose scree material.