Assessing Seismic monitoring for Shale gas exploration (ASeiS)

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This NERC Innovation Placement will embed the required expertise in the Environment Agency (EA) to efficiently and appropriately regulate hydraulic fracturing (HF) activities for the exploitation of shale gas/oil reserves in the UK. This is crucial for the short- and long-term success of the industry, which has significant potential worth to the UK's economy. The EA's remit includes the requirement to protect groundwater from pollution as a result of high pressure and volume HF and operators of shale exploration sites must submit a Hydraulic Fracturing Plan (HFP) to the EA for approval. This should include how the company will monitor the movement of HF fluids to verify they do not transgress the permitted boundary for exploration. Passive seismic monitoring (PSM) is currently considered the most appropriate method to achieve this because seismic event locations can indicate the extent of fluid migration. However, this type of monitoring is not a perfect solution and there remain uncertainties in the reported results. This project will embed geophysical knowledge in the organisation so the EA will be equipped to1. Evaluate proposed PSM and other geophysical methods for their suitability for the task;2. Assess the probability of a leaking wellbore in the event of a seismic event close to an active exploration site;3. Understand developing technologies and assess when they become acceptable monitoring solutions. To achieve these objectives, I will work with key EA staff in the Oil and Gas Programme, notably Simon Dawson (Technical Specialist in Geophysics) and Marion Maloney (Senior Advisor in Energy and Emerging Issues), to transfer scientific knowledge and the latest research in PSM. I will collaboratively develop and deliver two versions of a one-day workshop for EA staff to provide them with knowledge in basic earthquake source parameter estimation (e.g., location and magnitude) and current (e.g., geophone) and developing (e.g., fibre-optic) technology. With these staff, I will also build assessment criteria for proposed monitoring set-ups to improve the efficiency of HFP assessment. Additionally, I will develop a tool for the EA to assess the likelihood and extent of damage to a wellbore if seismicity is recorded. This tool will make use of available seismic event locations, magnitudes and fault plane solutions to model the probability that a wellbore has experienced deformation of a given displacement, thereby allowing an assessment of the risk of groundwater pollution.The key challenge faced by the EA is that there are knowledge gaps in geophysical monitoring amongst its staff. The Agency's regulation of the conventional oil and gas industry in the UK does not require any seismic monitoring plans. In the past, there has therefore been no need for specialised geophysical knowledge, in particular in PSM, at the EA. With shale gas exploration due to restart in the UK in 2017 the EA expects to receive HFPs from several exploration companies in the coming year. It is vital that this nascent industry, which has been and will be subject to significant public scrutiny, monitors projects appropriately and proportionately. Furthermore, the EA must be able to provide an expert assessment of HFPs to ensure safe operations and to avoid undue financial burdens on companies caused by excessive monitoring requirements. This project will put in place an efficient process to assess HFPs by well-trained EA staff.With over 10 years' experience and more than 10 international, peer-reviewed publications on seismic monitoring and estimating source parameters for seismic events, I am well placed to deliver this project. My background includes over 5 years working on microseismic monitoring of industrial fluid injection projects (carbon sequestration and hydraulic fracturing). This research has significant implications for the regulation of hydraulic fracturing in the UK and I am in an excellent position to communicate this to the EA.