Isotopic characterisation of methane and ethane within groundwater aquifers: assessing sources, flow pathways and the impact of shale gas exploration in the Vale of Pickering, UK.

Hydraulic fracturing (‘fracking’) is highly controversial with public concerns over environmental impacts, not least the risks to groundwater. Key among the concerns are the risks of stray gases from the deep subsurface entering aquifers via well casings or faults. With shale-gas exploration expected imminently at sites within northern England, it is of critical importance to understand sources and flow pathways associated with the gases methane (CH4) and ethane (C2H6). The key tracer tool for distinguishing sources and flow pathways is the combined stable isotope composition of both carbon (δ13C) and hydrogen (δ2H). This technique relies upon the distinct isotopic endmembers associated with thermogenic and biogenic CH4. This dual isotope approach can identify methane sources, evaluate integrity of geological structures, and discriminate any future gas migration as shale-gas exploration proceeds. This project focusses on a testbed site for shale-gas exploration in the UK – the Vale of Pickering, North Yorkshire. Here, baseline concentrations of methane in groundwater are high, by both national and international standards.

The project aims to: 1) Undertake a rigorous assessment of gas dynamics in groundwater aquifers to understand naturally high concentrations in the Vale of Pickering; 2) Identify and analyse natural gas endmembers; 3) Sample methane and ethane from different depths through the subsurface to identify flow pathways and gas interactions; and 4) Assess changes in gas flow routing and sources during fracking activities. We are looking for a highly motivated individual who is confident working in the field and laboratory. Experience in geoscience or engineering is beneficial for instrument development work. Training in field sampling, dissolved gas analysis, stable isotope analysis, hydrological modelling and data interpretation will be given. The successful candidate will be expected to present their findings at international conferences and contribute to the development of natural gas research at the stable isotope facility.

This project will have additional financial and student development support through BUFI (BGS University Funding Initiative):

https://www.bgs.ac.uk/research/bufi/home.html

A good science or engineering degree is required, preferably with some knowledge of geochemistry or groundwater science and laboratory experience.

Please contact Dr Andrew Smith via email andrews@bgs.ac.uk or phone 01159363541.