Is it time to rethink our approach to natural resources in Yorkshire?
What contribution to the energy transition is possible?
Nick Shaw, University of Leeds, School of Earth and Environment
Its over 200 years since William Smith and his nephew John Phillips started to document the lay of the land and publish geological maps. However, before
that the Romans and later the monks, miners , canal builders or railway entrepreneurs used their knowledge and experience to develop the natural
resources. In addition to this tacit understanding – gentleman geologists, university academics and industrial scientists have built-up and documented our
knowledge often accelerated at times of war.
The Yorkshire Geological Society published the classic “The geology and mineral resources of Yorkshire” edited by Rayner and Hemingway in 1974. Since then,
our coal mining industry has closed-down and onshore hydrocarbon exploration and production has had a limited success and even less social acceptance. In
the intervening period many new insights and understandings have been developed in geoscience – how the earth works – from inside the subsurface and
how human activity has influenced the planet’s climate, including recognition of the Anthropocene and impacts of the Industrial Revolution.
The geological history of Yorkshire is punctuated by three major unconformities and record major development phases. Despite the relatively gentle stratal
dips generally to the East or South-East there are underlying tectonic fabrics which control the basin development and sediment provenance, focus of heat
flow and thermal maturity, ore mineralization and fluid movements. Recent studies have indicated that the opening of the Atlantic and associated igneous
doming and dykes was significant in shaping the outcrop pattern including offshore.
Coal, iron, lead, zinc, salt and hydrocarbon deposits have long been developed as extractive industries perhaps now some of these legacy industrial assets
might be repurposed become managed natural resources. They might therefore contribute to the energy transition as sources of geothermal heat and/or storage, seasonal gas storage or sequestration of CO2 or nuclear waste repositories.
Nick Shaw has had a long career with Shell working on conventional and unconventional hydrocarbons around the world, deep and shallow geothermal energy and at the University of Leeds leading research on the ‘energy transition’.
He gave an initial exposition of the long history of the extraction and use of natural resources in Yorkshire and then the development of the geological understanding of the subsurface and how the earth works over the past two hundred years.
He remarked on how enduring was the classical view of the subsurface as found in the work of William Smith and John Phillips, especially in their ‘adopted’ county of Yorkshire.
He described how forensic geologists like to review boundaries and unconformities, making subtle adjustments and, more recently, offering insights into major local and global changes on land, in the seas and the atmosphere of the deep past.
The three unconformities in Yorkshire are the Upper Palaeozoic at Ingleton, the Carboniferous/Permian around Knaresborough and the Jurassic/Cretaceous at Market Weighton. Studying these and mineralisation within the North Pennines, the granite batholiths underneath and the later igneous dykes and sills has led to the descriptions of plate tectonic activity, mountain-building and cyclical changes in climate driven by precession of the earth’s rotation. The evolution of lignum produced the high levels of atmospheric oxygen that allowed tall vegetation cyclically swamped by sea level rises to produce the coal measures
His next section was on the most recent research on data from onshore and offshore seismic, boreholes and wells and Coal Authority. This shows the east/west stresses and faulting across the county, as the UK has rotated by 30 degrees, and the consequences for problems in the extraction of coal and fracking – especially in the east of the county.
This led to the main focus of the talk: the resulting man-made climate changes from the Industrial Revolution onwards and the possibilities within the county for transitioning to the cleaner use of energy. Several possible routes will require the collaboration of industry, universities and Government in the geological investigation of subsurface and integrated engineering schemes.
Nuclear energy needs a plan for the vast amounts of nuclear waste produced in the past as well as the future; a plan for deep geological burial of nuclear waste is in development. Abandoned coalfields, especially in North Selby and North Nottinghamshire are sources of geothermal warm water which could be tapped for direct use (eg greenhouses, swimming baths) or combined with heat pumps to produce electricity. Blue hydrogen production from methane (North Sea gas) would be clean to use, but the process produces CO2 which could be pumped back where oil and gas has been extracted in Triassic sandstones. CO2 from other sources or even the atmosphere can be stored in liquid form in the same way.
For all of these, reservoir quality, seal effectiveness and source rock maturity must be established to ensure the safety of aquifers and other drinking water. And all this requires a government willing to look much further than the next election.