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Local Geology
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Mica Schist
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Hornblende Schist
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| Slates
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From Mottershead (1971)
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The southern coast of the South Hams between Bolt tail and Start point,
sticks out 5-6miles from the rest of Devon. This is due to the hard
weather resistant schists this area is made up of, which protect the
weaker slates to the north. The boundary between the two goes from slightly north of Hope Cove to Marble Rocks in Hallsands. The schists fall into two types: Mica schists - These are grey rocks with a shiny surface caused
by sheets of mica forming there. They are cut through by numerous veins of
quartz.
Hornblende schists - These are green schists with a sandy
texture. The green colour comes from the green mineral Hornblende.
Interesting features caused by wind errosion can be seen on prawle point
itself to the SW of the lookout.
The Hornblende Schist is on top of the mica schist, although at the
border to the east of Langerstone point, there appears to be a region
where layers of one are inside teh other. On the large scale there appears
to be an anticline Schists are metamorphic rocks and these have undergone several
deformations. The first and probably most extreme phase has formed a
cleavage, and this has subsequently been folded to a great extent.
Mica Schist at Peartree Point |
Horneblende Schist |
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