National Geological Screening for a GDF - Northern England Region
Our work shows that we may find a suitable geological setting for a GDF in some parts of this subregion.
Rock can be seen at the surface at some places in this subregion such as the inland cliffs in the Pennines and in man-made excavations such as quarries or road cuttings. Combined with some deep boreholes and geophysical investigations, this gives us an understanding of the rocks present and their distribution.
There are granites, volcanic lavas and similar strong rocks under the centre of the subregion centred on Weardale, in which we may be able to site a GDF. There are also layers of rock salt around Hartlepool and Teesside, in which we may be able to site a facility. We would need to do more work to find out whether these rocks have suitable properties and thicknesses in the depth range of interest for a GDF.
Some of the sub-region has been mined to depths below 100m for coal resources, in the major Northumberland and Durham Coalfield and to the west near Hexham, Haltwhistle and Alston, and lead, fluorite and zinc, around Alston and Weardale. 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.
A small part of the south-east of this subregion has 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.
Parts of this area, and much of the near inshore in particular, are Coal Authority Licence Areas allowing companies to explore for coal. It is not known if coal in these licence areas will be exploited. RWM will also continue to monitor how this exploration programme progresses.
Parts of the subregion which have been mined for anhydrite, rock salt and potash, in the vicinity of Teesside, would also need to be taken into account in the siting of a GDF, although the nature of mining in evaporites does not affect the movement of groundwater in the surrounding rocks in the same way as other mining.
For further information, read the report below.
We have also produced a summary of the geological attributes of the Northern England Region.