Lead Doc - An integrated assessment of UK Shale resource distribution based on fundamental analyses of shale mechanical & fluid properties.

Lead Research Organisation: Imperial College London
Department Name: Earth Science and Engineering

Abstract

Shale gas has the potential to transform the UK's future energy security. With imports currently accounting for 50% of its domestic gas requirements, projected to rise to roughly 80% by 2035, the big question is 'Are there enough shale gas resources to effectively replace the declining North Sea and Irish Sea gas production, and for how long?' The largest unknown is the potential gas reserves (i.e. recoverable resources) that would be commercially viable to be produced in the UK. There have been a number of differing in-place estimates for the Upper Bowland Shale in the northern England Carboniferous, ranging from 164-447 tcf suggested by Andrews (2013), to 8-19 tcf quoted by Uguna et al. (2017). In the absence of flow test data, reliable recoverable reserves estimates could not have been published. There has been a single well test carried out by Cuadrilla in Lancashire, the results of which have not yet been made public. The industry, the scientific community, the government, and environmental scientists, have been starved of modern borehole electric log, core and well test data with which to assess both resource potential and the associated environmental impact. This is about to change, with drilling planned to take place during the course of the proposed study in Cheshire, Lancashire, North Yorkshire, and North Nottinghamshire.
This research project will focus on the Carboniferous (Bowland Shale) basins of the East Midlands, Lancashire, Cheshire, and Yorkshire. The vision is of a multidisciplinary approach to solving problems in the main research focus areas set out in Challenge 2 of the NERC call. We will bring together key researchers from several institutions around the UK, working on UK shale science from the micro-pore (<10 nm) to the basin scale. Key aspects of shale mineralogy, petrology, geochemistry, stratigraphy, rock mechanics, gas generation and adsorption and fluid flow in low porosity rocks will be combined into a holistic basin-scale model to generate a better scientifically-grounded set of estimates. Key sensitivities related to input parameters will be tested, and more importantly, compared/contrasted with available production data from the planned wells .
The outcome of this 4-year project will be a more scientifically defendable assessment of the location and magnitude of UK shale resources, guided by an improved understanding of the shale properties and fluid flow through the shale, before, during and following hydraulic fracturing to ascertain whether shale gas has the potential to have a marked impact on energy security in the UK for several decades into the future. This project will critically inform the key stakeholders (Government, Industry, Academia, and the general public) of UK shale potential, and will provide input to discussions on future UK energy strategy. Collaboration with those projects funded within the other Challenges in this programme will allow us to assess whether or not this resource can be accessed in a commercially viable and environmentally responsible way.

References
Andrews, I.J. 2013. The Carboniferous Bowland Shale: Geology and resource estimate. British Geological Survey for the Department of Energy and Climate Change, London, UK.
Uguna, C., Snape, C., Vane, C., V. Moss-Hayes, V., Whitelaw, P., Stevens, L., Meredith, W. and Carr, A. 2017. Convergence of shale gas reserve estimates from a high pressure water pyrolysis procedure and gas adsorption measurements. 28th International Meeting on Organic Geochemistry, 17-22 September 2017, Florence, Italy.

Planned Impact

The research carried out in the proposed project will address to fundamental questions related to UK Shale gas. Namely: How much gas and where is it located? Stakeholder interest in accessing new, scientifically calibrated estimates of resources and reserves will be of immense scientific, industry and public interest. Government will also use these outcomes to inform energy policy in the UK for potentially the next 20 years. Regular communication with the other Challenges in this call and industrial partners will take place at a minimum of 6 month intervals. There will also be formal reporting requirements to the funding bodies.

Beneficiaries

Industry
Depending on which current shale gas resource estimates we take (BGS: Andrews 2014) or Urgano (2017) and the recovery factor applied (nominally 10%) the UK would appear to have between 10 and 50 years of potential gas supply from the northern England Carboniferous basins. Assuming UK gas consumption continues at the current rate of approximately 2.7tcf/year. The value of narrowing the range on this estimate cannot be understated. Working with industry partners we can critically test current and evolving academic models of pore and fracture systems in shales against new data acquired by industry. The models will be re-calibrated with real well bore and test data to provide revised models of pore and fracture behaviour. The key to industry and the country is more efficient exploration and exploitation activities. Fewer wells, fewer pads equals less disruption, less emissions and consequently minimised environmental impact.

Government
Having a scientifically supported range of resource estimates for UK shale gas and its location is of immense value to government in terms of framing UK energy policy going forward. CO2 emission commitments require a cleaner energy policy based on gas rather than coal and oil and a resource that is indigenous from either the North and Irish seas and potentially onshore UK. This mitigates emissions related to transportation and the valid criticism that imported gas is just shifting the problem onto someone else.

General Public
One of the key roles we have to play as an informed group is in explaining to the general public from a scientific expert point of view the key pluses and minuses associated with shale gas and the impact of fracking and a potentially large resource might have on industrialisation and environment in the areas we identify that may contain the gas resources.

Publications

10 25 50
 
Description Bowland shale - why it won't work

Roughly 12 years ago, industry and academia enthusiastically embarked on UK shale gas research with the premise that the organic rich Bowland Shale and equivalents in northern England would provide UK shale gas resources that could fill an ever-widening gas supply gap from the rapidly declining North Sea production. Initial in-place estimates published by the BGS (Andrews 2013) based on a possibly over optimistic interpretation of the organic content of the deeper basin fill (Bowland, Hodder and equivalents), appeared to support the general optimism. However, having completed research involving geochemical, mineralogical and petrological analysis of over 100 core samples for this study and complimentary sampling for other studies e.g., Hennissen et al this volume; Sims et al, this volume suggests a markedly different and more pessimistic resource outlook. To summarise the key negative factors are the wrong type of basins (rift rather than foreland) and post depositional structural complexity.

In summary, technical support for the resumption of on fracking in the UK is not supported by the research reported here. We conclude some gas could be produced from the Bowland Basin which has the required maturity levels for dry gas but feel that resources are unlikely to justify further activity. Some oil and gas could also be produced from the less structured Gainsborough Trough but the most prospective area is small (in the area of the existing Beckingham-Gainsborough Field) and of marginal maturity for gas (Palci et al. 2020). Oil is probably a more likely product here.

Our main conclusion is that the Bowland Shale and equivalents in the UK do not represent a technically significant resource and in hindsight did not merit the considerable industry and media attention that has been associated with it. A key learning is that fundamental research based on heritage data and modern analytical and modelling techniques could usefully have preceded drilling and fracking operations in northern England.

In 2010, when Cuadrilla drilled the Preese Hall-1 shale gas exploration well in Lancashire, the UK was in an excellent position to develop a sound technical shale gas resource evaluation and investment strategy. This would build on a 50-year history of North Sea oil exploration and production, an academic community with recognised expertise in petroleum related teaching and research, and a world class archive of heritage core, seismic and well data hosted by the British Geological Survey at Keyworth in Nottinghamshire.

Several factors contributed to shale gas operations commencing before the fundamental research was in place. The major North Sea operators such as Shell & BP with access to critical expertise and data, declined to take up exploration licences for UK shale gas. This left the field open to a dominance of underfunded and technically inexperienced exploration companies whose business objectives didn't necessarily align with the public interest, and who were slow to fund the necessary research in UK universities. It was not until 2014 that the government, through NERC and ESRC actively funded research into UK shale gas resources. Prior to this, the void was largely filled by an underfunded geological survey that was slow to identify and respond to the issues and out of its depth when it was allocated the shale gas resource evaluation task.
Exploitation Route Government, public and industry. Recent calls for lifting of fracking ban not supported
Providing an understanding of the link between hydraulic fracturing and induced seismicity. This has direct relevance to resource estimation in that without artificial stimulation of the Bowland Shale Formation there are effectively no resources.
Faster response times recommended by research funding bodies to provide scientific basis for conscious issues such as Shale Gas in the UK
Sectors Energy

Environment

URL http://www.ukuh.org/events/annualsciencemeeting1
 
Description Results of observed and modelled impact of induced seismicity during fracking operations used by UK Shale operators Cuadrilla and IGas. Recent assessment of reduced Shale Gas reserves in UK now being communicated to both industry, academic and public communities. Results will be published as a set of 3 peer reviewed papers to be included in a major Geological Society volume later this year.
First Year Of Impact 2000
Sector Energy
Impact Types Societal

Economic