Wales - Subregion 5

National Geological Screening for a GDF - Wales region


Wales, subregion 5

Our work shows that we may find a suitable geological setting for a GDF in most of this subregion, but the lack of information at depth makes it difficult to know where the potential host rocks have suitable thicknesses and properties.

Although rock can be seen at the surface over much of this subregion in sea cliffs, mountainous areas and man-made excavations such as quarries and road cuttings, there are very few deep boreholes and geophysical investigations, to give us an understanding of the geology at depth.

There are various types of gaps in our understanding of geology and we deal with these gaps in a number of ways.

There are slates and similar strong rocks under most of the subregion in which we may be able to site a GDF. They can be seen at the surface in Snowdonia and quarries such as Dinorwig near Llanberis and Penrhyn near Bethesda.

These rocks are varied, folded and faulted and we would need to do more work to find out whether they have suitable properties and thicknesses.

Some of the subregion has been mined to depths below 100m for metal resources such as copper, lead and zinc, such as north of Dolgellau and Anglesey. In these areas the mining is likely to have affected the way in which water moves through the rock. Also possible exploration in the future in these areas means that it is more likely that future generations may disturb a facility.

Two areas in the inshore part of the subregion have Petroleum Exploration & Development Licences to allow companies to explore for oil and gas. This exploration is currently at an early stage and it is not known whether oil or gas in these licence areas will be exploited. RWM will continue to monitor how this exploration programme progresses.

For further information, read the report below.

Wales Subregion 5

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We have also produced a summary of the geological attributes of Wales.

Go to National Geological Screening for a GDF

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Published 19 December 2018
Last updated 16 January 2019 + show all updates
  1. Added translation in Welsh
  2. First published.