Cuadrilla is currently exploring the Bowland shale rock in Lancashire for natural gas. The gas trapped within this rock is no different to the natural gas which we all use every day in our homes, businesses and communities.
Cuadrilla retained Anderson Thompson, a team of reservoir engineers, geoscientists and hydraulic fracturing specialists, to undertake analytical research on likely gas recovery volumes from horizontal wells to be drilled in the Lancashire Bowland shale. Anderson Thompson has broad international basin experience and specialist knowledge of the Permian, Eagle Ford, Bakken, Marcellus and Montney shale plays in North America.
Using input data from the Lancashire Bowland exploration wells that Cuadrilla has drilled to date, including the Preese Hall well, which was hydraulically fractured and flow tested in 2011, Anderson Thompson modelled potential gas recoveries from a 2.5km horizontal well. The results of this modelling forecast that, over a 30 year period, a most likely volume of 6.5 billion cubic feet (Bcf) of gas would be produced from a 2.5km horizontal Bowland shale well.
Expected Gas Production For a 2.5km Horizontal Well Over a 30 Year Period
The mineralogy of the Lancashire Bowland shale has been analysed in detail using X-ray diffraction of shale core samples and cuttings taken from the Preese Hall well. This analysis has confirmed that both the Upper and Lower Bowland shales are very well suited to hydraulic fracturing as they are formed from a highly siliceous matrix with consistently low overall clay content and not reactive clays.
Hydraulic fracturing – or fracking as it is sometimes called – is the long established process of creating fractures in rock formations to release the natural gas trapped inside. It has taken place for decades in the UK, with the first treatment thought to have taken place in the mid-1970s. Our site in Elswick was fractured in 1993 and generated around 1MW of electricity seven days a week in its early life. Hydraulic fracturing is common in the North Sea, where it has been performed thousands of times.
The hydraulic fracturing operations carried out by Cuadrilla in the Bowland Basin in Lancashire takes place at depths generally greater than 6,000 feet – that is almost 13 times the height of Blackpool tower!
In advance of performing hydraulic fracturing, our engineers and geologists analyse all available technical data, including rock properties and wellbore mechanics, to ensure that the process is undertaken safely.
Fracturing fluid – 99.95% water and sand – is released at high pressure into the rock formation to create millimetre-sized cracks. These cracks are held open by sand grains contained within the fluid, allowing the gas to flow into the wellbore and be collected at the surface.
Watch our “What’s Fracturing” video here.