Bishops and Clerks

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For the Australian islets, see Bishop and Clerk Islets.
View northwest from Ramsey Island showing some of the islets around Carreg Rhoson

The Bishops and Clerks are a group of rocks and islets situated in St George's Channel 1 to 2 miles west of Ramsey Island, Pembrokeshire, Wales.

Geography[edit]

There are four distinct groups of islets. From the north these are:

  • North Bishop (44 metres, 144 feet)
  • Carreg Rhoson (44 metres, 144 feet)
  • Carreg Rhoson E Island (30 metres, 98 feet)
    • Maen Rhoson
  • Daufraich
    • Maen Daufraich
    • Moelyn
    • Cribog
  • Emsger or South Bishop (37 metres, 121 feet)

In addition, the three small wave-washed rocks of Carreg-trai, Llechau-isaf and Llechau-uchaf sit in the waters between the Bishops and Clerks and Ramsey Island and the Welsh mainland.

Lighthouse[edit]

The South Bishop Lighthouse is built upon Emsger or South Bishop. Thirteen or so shipwrecks are recorded in the waters immediately surrounding the islands, notably North Bishop.[1]

Geology[edit]

The two northerly islet groups are formed from gabbro, a hard-wearing rock of igneous origin whilst those of the Daufraich group to their south (and indeed Llechau-isaf) are formed from microtonalite, another intrusive igneous rock. The most southerly, Emsger is formed from rhyolite. All these are of probable lower Palaeozoic origin. Llechau-uchaf is formed from the late Cambrian 'Lingula Flags' whilst Carreg-trai is formed from Ordovician acid tuffs of the Llanrian Volcanic Formation.[2] The submarine geology between the main groups is formed by sandstones and mudstones of Cambro-Ordovician age, though the bedrock is partly covered by sand and gravel.[1]

References[edit]

  1. ^ a b "Pembrokeshire Coast National Park planning document" (PDF). 
  2. ^ British Geological Survey 1992 1:50,000 scale provisional geological map sheet 209 (England and Wales) St David's

External links[edit]

Coordinates: 51°52′12″N 5°23′42″W / 51.87°N 5.395°W / 51.87; -5.395