Harlech Dome

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The Harlech Dome is a geological dome in southern Snowdonia in north Wales. It extends approximately from Blaenau Ffestiniog in the north to Tywyn in the south, and includes Harlech, The Rhinogydd, [1] Barmouth and Cadair Idris. [2]

The geological layer structure comprises Cambrian sedimentary, volcanic and intrusive rocks from the lower Paleozoic age [2] approximately 4.5 km thick. [3] The geology contains the Harlech Grits Group, Mawddach Group, Rhobell Volcanic Group and Aran Volcanic Group. [2]

The area contains a wide range of metallic minerals and has been mined for (copper, [4] silver, [4] zinc, [4] manganese, [5] gold [4] [6] [7] ) in the past. [2]

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References

  1. "Rhinogydd". The Snowdonial. Archived from the original on 29 November 2014. Retrieved 16 November 2014.
  2. 1 2 3 4 "Mineral Reconnaissance Programme Report No 74 - "A reconnaissance geochemical drainage survey of the Harlech Dome, North Wales" (1985 PDF - mineralogical report, 113pp)]". British Geological Survey, Natural Environment Research Council. Retrieved 14 November 2014.
  3. "Cambrian rocks in Wales". Countryside Council for Wales. Archived from the original on 29 November 2014. Retrieved 14 November 2014.
  4. 1 2 3 4 "Mineral exploration in the Harlech Dome, North Wales". NERC Open Resesarch Archive. Retrieved 16 November 2014.
  5. "Geology - Harlech Dome". Merioneth Manganese. Retrieved 16 November 2014.
  6. "The Geology of the Barmouth and Arthog area". Bernard O’Connor. Retrieved 16 November 2014.
  7. "Chasing ancient microcontinents in North Wales - the Megumia project". Geology Wales. Retrieved 16 November 2014.

52°52′N3°55′W / 52.86°N 3.91°W / 52.86; -3.91