The BGS Hydrothermal Laboratory enables the study of chemical reactions between fluids and rocks under conditions found in the top few kilometres of the Earth's crust. In its 30+ years, it has been at the centre of numerous investigations that require well-controlled conditions to study reaction processes under in-situ conditions (i.e. elevated temperatures and pressures). The lab contains a variety of equipment capable of maintaining controlled conditions for timescales of up to many years. Reactions are followed by various means, including: visual observations, monitoring fluid chemical changes over time, and detailed mineralogical analysis of the reaction products. The experimental reaction products are characterised using a wide range of fluid chemical and mineralogical analytical techniques that are available within other dedicated laboratories at the BGS.
The hydrothermal laboratory is the leading laboratory within Europe for the study of the chemical and mineralogical changes caused by stored CO2, (including other acidic impurities in the CO2), on reservoir rocks (e.g. sandstones and limestones) and caprocks (e.g. clays and evaporites), the impact of stored CO2 on borehole infrastructure (i.e. borehole steel and cement), and how these contribute to long-term safe storage.
Static (batch) and flow-through equipment are available in the laboratory, with useable volumes ranging from less than one ml to over ten litres, although they have variable pressure and temperature limitations up to 600°C and 1500 bar.
Various arrangements of reactors are available, and include:
More extreme conditions can be simulated with minor modifications. Most of the equipment in use in the laboratory has been custom designed to suit our specific needs, with much of it manufactured within the BGS workshops. It is possible therefore, to construct specialised equipment to address the needs of specific studies. Many of the experiments conducted are ‘one offs’, and are individually tailored to the needs of the project concerned. The Hydrothermal Laboratory is unique (within the UK at least) in the wide range of techniques and equipment it has available. Reactions are tracked by fluid chemical changes and detailed mineralogical analysis of the reacted solids. Additionally, the lab can derive the fundamental data on reaction processes and rates that underpin predictive geochemical modelling of how the rocks will react on a longer timescale.
The BGS Hydrothermal Laboratory has a long track-record of involvement in many national (NERC, EPSRC, UK government) and international projects, working with academics and operators across Europe, and worldwide (e.g. NDA, SKB, Nagra, JAEA, Statoil). The laboratory regularly attracts researchers from universities (MScs, PhDs and Post Docs) who have found the facilities and supervision very beneficial to their investigations. For example, the laboratory is a key part of the GeoEnergy Research Centre (GERC) a pioneering joint venture co-established by the British Geological Survey (BGS) and the University of Nottingham, and 3 GERC PhD students are currently linked to the lab. The laboratory personnel have a widereaching scientific impact, coordinating large-scale projects and publishing widely as a result.