West Cornwall - Geology
Sheeted Veins - Porth Chapel (S18)
At Porth Chapel numerous veins of Quartz and Tourmaline ...can be found in the cliffs and across the rocky foreshore.
When the Granite Mass was in the process of Crystallising cracks developed allowing pressurised fluids
to further fracture the Granite forming parallel cracks perpendicular to the direction of least stress.
Hot silica-laden hydrous fluids separating out from the crystallising granite circulated along these
parallel cracks to form sheeted vein systems.
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Porth Chapel is to the west of Porthcurno in Gallery 18
Ref: 5435
Date: 07/12/2017
Location: SW 3815 2191