OR/17/048 Foreword

Fellgett, M W, Kingdon, A, Williams, J D O, and Gent, C M A. 2017. State of stress across UK regions. British Geological Survey Internal Report, OR/17/048.

New and emerging subsurface energy technologies and the extent to which they might make a major contribution to the energy security of the UK, the UK economy and to jobs is a subject of close debate. The complexity of geological conditions in the UK means that there is a need to better understand the impacts of energy technologies on the subsurface environment. Our vision is that the research facilities at the UK Geoenergy Observatories will allow us to carry out ground-breaking scientific monitoring, observation and experimentation to gather critical evidence on the impact on the environment (primarily in terms of the sub-surface and linking to the wider environment) of a range of geoenergy technologies.

The Natural Environment Research Council (NERC) through the British Geological Survey, the UK environmental science base and in collaboration with industry, will deliver the UK Geoenergy Observatories project comprised of two new world-class subsurface research facilities. These facilities will enable rigorous, transparent and replicable observations of subsurface processes, framed by the Energy Security Innovation and Observing System for the sub surface Science Plan. The two facilities will form the heart of a wider distributed network of sensors and instrumented boreholes for monitoring the subsurface across the UK. Scientific research will generate knowledge applicable to a wide range of energy technologies including: shallow geothermal energy, shale gas, underground gas storage, coal bed methane, underground coal gasification, and carbon capture and storage.

The UK Geoenergy Observatories project will create a first-of-its-kind set of national infrastructure research and testing facilities capable of investigating the feasibility of innovative unconventional and emerging energy technologies. Specifically, the project will allow us to:

• deploy sensors and monitoring equipment to enable world-class science and understanding of subsurface processes and interactions
• develop real-time, independent data capable of providing independent evidence to better inform decisions relating to unconventional, emerging and innovative energy technologies policy, regulatory practice and business operations in these technology areas.

This report is a published product of the UK Geoenergy Observatories project (formerly known as the ESIOS project), by the British Geological Survey (BGS) and forms part of the geological characterisation of the Cheshire site. The report describes the data available to characterise the onshore in-situ stress field near Cheshire and two other UK regions. This report also compiles all of the available data on the maximum horizontal stress. Key outputs include estimates of vertical, stress pore pressure and minimum horizontal stress in the Cheshire and Lancashire region.

This report is based on data as compiled by 31-Jan-2016, additional Hydraulic Fracture data from the Coal Authority may be available. It does not include any data from the World stress Map database (Heidbach et al., 2016) which could not be independently verified at the time of writing. Some data may since have been collected.