Cumbria and Northumberland

Regional summary

In Cumbria and Northumberland, 16 sites have been sampled for methane in a number of different aquifers. The two main aquifers are Permo-Triassic sandstone and the Fell Sandstone and Border Group.

Geology of Cumbria and Northumberland.

Permo-Triassic sandstone is the second most important aquifer in the UK. It has a high porosity, meaning groundwater flows through pore spaces in the rock. The majority of the Carlisle Basin is Triassic sandstone; this can be up to 600 m thick and is made up of sandstone, conglomerates and marls. The southern part of the Carlisle Basin is Permian sandstone consisting of sandstone, marls and breccias.
The Fell Sandstone and Border Group is an important aquifer for the very north east of England, stretching west to Carlisle where it reaches great depths. It can be up to 300 m thick and is made of quartz rich sandstones with silty or pebbly bands.

The shale units present in the Northumberland Trough are the Bowland Shale and other black shales of Visean to Tournaisian age that are typically interbedded with sandstone, siltstone and mudstone. These shales are thinner, shallower and not laterally extensive when compared to the Bowland Shale Formation in Lancashire and Yorkshire. Oil shale is present in the Tweed Basin, but at shallow depths. In the west of this region, the coal seams of the Pennine Coal Measures Group are reported to have potential for coal bed methane.

Methane in UK groundwater results

These summary results are from single sampling visits to each site as part of the methane baseline project. The data are summarised for the Cumbria and Northumberland region as a whole and also for individual aquifers, where enough data are available.

Methane samples and concentrations in Cumbria and Northumberland.

Methane concentrations chart for Cumbria and Northumberland.

Area	Concentration (mg/l)			Number of samples
Area	Minimum	Median	Maximum	Number of samples
Cumbria and Northumberland	0.0002	0.00065	1.434	16
Permo-Triassic sandstone	0.0002	0.0005	0.0296	7
Fell Sandstone and Border Group	0.0002	0.0002	0.0006	3

Methane samples and concentrations in Cumbria and Northumberland.
Note: values less than the analytical detection limit have been converted to half the detection limit for the purposes of this statistical summary and graph, but the relevant detection limit is quoted in the table above.