World-class facilities and expertise is available for elemental and isotopic micro- and macro-analyses of a wide range of geochemical samples.
Continuous development of cutting-edge instrumentation and measurement methods, make it possible to analyse small samples with high levels of precision that are not normally available.
The department has a range of custom designed laboratories including analogue modelling and computer laboratories for our collaborative research programmes.
The facilities are available for commercial analysis, collaborative research, internal projects and training courses.
Mineral separation laboratory
The Southeast Asia Research Group (SEARG) manages a mineral separation laboratory for heavy/light mineral studies for sedimentary provenance work, as well as to obtain minerals for geochronology and geochemistry.
The Department of Earth Sciences has all of the facilities required for processing rock and sediment samples for mineral separation. A jaw crusher is typically used to break down rock samples into smaller aggregate before being processed in a tungsten-carbide or steel swing/ring mill or our newly purchased Fritsch Pulverisette 13 Premium Line tungsten-carbide disk mill.
The milled ‘sediment’ is then sieved using disposable nylon meshes and a Retsch vibratory sieve shaker, before being deslimed. Ovens and heat lamps are available to dry any slurries before further processing using a Wilfley (‘shaker’) table, heavy density liquids (LST and DIM) and/or Frantz isodynamic magnetic separator.
We use the following techniques for mineral separation.
- Rock crushing (available in our adjoining facility)
- Rock milling/pulverizing
- Heavy density liquids (LST and DIM)
- Magnetic separation
- Transmitted and reflected light microscopy
Light stable isotope laboratories
The laboratories house 4 mass spectrometers and a range of preparation systems.
A newly refurbished laboratory houses 3 IsoPrime mass spectrometers.
Continuous He-flow to analyse:
δ13C and δ18O of DIC in waters by multiflow
δ18O by equilibration of the water itself by multiflow
δ13C and δ15N of rocks, minerals, soil and vegetation by Elementar MicroCube EA
Continuous He-flow to analyse:
δ13C and δ18O of carbonates by multiflow
dD of waters by Cr-reduction
Dual inlet mass spectrometry to analyse:
δ13C and δ18O of small sample carbonates (20-200µg)
multicollector capabilities to measure masses 47 and 48 in carbonates
A second lab houses our oldest mass spectrometer a 1994 Optima dual inlet mass spectrometer. This has the following preparation systems attached to it:
- LaserPrep, designed and built at RHUL for laser heating of minerals in an atmosphere of BrF5 to release oxygen for the measurement of 18O/16O and 17O/16O ratios.
- Fisons NCS1500 elemental analyser for flash combustion of rocks, soils and vegetation in an oxygen atmosphere to release CO2, N2 or SO2 for isotopic analysis.
Dr. D. Lowry
Dr. N. Grassineau
Prof. D. Mattey
Find out more
The current understanding of climatic influences of cloud formation has been described by the intergovernmental panel on climate change, IPCC, to be 'very low' and an examination of these processes is clearly required.
All cloud droplets form on atmospheric aerosol by taking up water vapour in atmospheric updrafts. The chemical composition of the aerosol determines whether it will activate to become a cloud droplet or not.
Cloud formation is of climatic importance since clouds reflect sunlight back into space and are thus responsible for cooling of the atmosphere. Cloud chemistry also determines the cloud water content and thus controls if a cloud will rain.
Atmospheric aerosol is often coated in organic films that may be one molecule thick. Such monolayers have the ability to lower the surface tension of the droplet and enhance cloud formation (Köhler theory). The atmosphere is oxidising and oxidative degradation of these organic films may increase the surface tension of the organic film and thus prevent cloud formation.
The lab tests whether the atmospheric oxidation is fast enough to compete with the lifetime of aerosol or cloud droplets. Aerosol films are generates on a Langmuir trough and oxidised with gas-phase and liquid phase atmospheric oxidants.
We use the following techniques to study the effect of atmospheric oxidation on aerosol. Principally to investigate the potential for atmospheric oxidation to lower the critical saturation point for cloud formation of an individual aerosol.
Neutron Scattering. (www.isis.stfc.ac.uk)
Optical trapping and Raman analysis of single aerosol. (www.clf.rl.ac.uk)
Filter analysis of Black Carbon
Dr Martin D. King
Greenhouse gas laboratory
The laboratory was set up in 1994 as part of a European methane project drawing on existing expertise in the measurement of stable isotopes. Since then the focus of the laboratory work has been on the carbon isotope measurement of methane and carbon dioxide. The RHUL site provides an important location for atmospheric monitoring as it picks up relatively clean air from the SW and air with London emissions from the E.
The laboratory has been developed as a long-term monitoring site for the atmospheric gases CH4, CO2, CO, H2, N2O and radon. Recent NERC and EC grants have seen the laboratory widen its remit, extending its greenhouse gas monitoring network to the islands of Ascension and East Falkland in the South Atlantic Ocean and Barra in the Hebrides of Scotland, with ongoing investigation of the isotopic signatures of methane sources in the Arctic. Since 2013 a mobile laboratory has been used to measure and identify methane source plumes.
- Dr. D. Lowry
- Dr. R. Fisher
- Mr. M. Lanoisellé
- Ms. B. Whiite
- Prof. E.G. Nisbet
Meth-MonitEUr Final Report
Meth-MonitEUr was a European Union Project from 2002-2005, to monitor Methane emissions in the European Union and Russia (total project €519,812). The scientific work of the project is described in Section 6 of the Final Report. This report was not externally peer-reviewed but did have rigorous internal scrutiny. It was externally assessed and accepted by the Commission. The reference is as follows:
Nisbet, E. G. (Ed.) (2005), Meth-MonitEUr: Methane monitoring in the European Union and Russia, Final Rep., Sect. 6, EC contract EVK2-CT-2002-00175. European Commission, Brussels.
The LA-ICPMS laboratory is used for direct in-situ elemental and isotope-ratio analysis of solid samples. We utilise a custom-designed/built deep-UV 193 nm excimer laser-ablation system coupled to an Agilent 7500ce/cs quadrupole ICPMS (or a GV Instruments IsoProbe MC-ICPMS).
The laser-ablation system was designed in close collaboration with Mike Shelley (Laurin Technic P/L, Canberra, Australia) and Resonetics LLC (Nashua, NH, USA) and is the prototype of the system now marketed as RESOlution M-50 (http://www.resonetics.com/la/). At its core, it features a Laurin two-volume laser-ablation cell characterized by both fast signal washout and uniform signal characteristics anywhere in the cell.
The system is extremely versatile, fully computer-controlled and easy to use even for beginners, since all is controlled by an intuitive image-directed software (Geostar). The large primary excimer laser beam in conjunction with aperture-imaging optics and a long working distance lens allows the use of a large range of round spot sizes from ~7 – 300 µm. Moreover, this includes a rotating adjustable rectangular slit that is especially useful for layered samples where the highest-spatial resolution along a growth axis has to be maintained without loss of element detection capability. X Y stage travel is 50 x 50 mm.
Dr Christina Manning
Scanning electron microscopy laboratory
Scanning electron microscopy (SEM) is a technique which enables the observation of solid materials at magnifications of up to X100,000. In addition to producing an image of the sample surface, it is also possible to obtain a chemical analysis (typically qualitative or semi-quantitative) of the material being observed.
The method is used for examining a wide range of geological materials (e.g. microfossils, fossil wood, minerals, tephra, sediment pore spaces), but has also been used to study other, non-geological materials (e.g. paint pigments, asbestos, semiconductors, modern plants and insects, archaeological materials).
Most samples can be examined uncoated but in some cases coating may be required (with carbon or gold).
We currently use a Hitachi S3000 SEM with an associated Link Isis energy-dispersive X-ray detection system for chemical analysis.
School seismology laboratory
Royal Holloway works in association with the British Geological Survey to provide financial, logistical and educational support for earthquake detectors in schools in our area. We currently have 18 school’s involved and have plans to install 6 more instruments over the next year. As part of this network, we have run our own school’s instrument since early 2008 and record several medium or large earthquakes per month from locations around the world. We provide training in the assembly and operation of the instruments either in schools or using our own facilities.
The strongest and earliest evidence of climate change (and previous climate change via ice cores) is forecast to occur in the polar regions of the planet. Polar surface are simulated in two large shipping container style cold rooms on a concrete stand. Each container has a different role.
Sea-ice has a strong modern climatic role in cooling the planet via the ice-albedo feedback. Small amounts of soot/black carbon (nanogram per gram of ice) allow ice to absorb solar radiation and melt. The optics of natural sea-ice are little understood let alone anthropogenically forced sea-ice, mainly owing to the logistical costs (danger and money) in studying sea-ice.
The effect of soot on snow and sea-ice has been listed in the latest IPCC climate change report as an important and little understood driver for modern climate change.
Sea-ice can be made fairly easily and safely in cold rooms. Large tanks of synthetic sea-salt are maintained at around 0°C and the air in the chamber cooled to lower temperatures. This produces a realistic sea-ice complete with brine channels and the correct depth structure to study the optics (albedo/ transmission/ energy uptake) of abiotic and biotic sea-ice.
The Sea Ice Simulator uses the following techniques to analyse the optical properties of sea-ice:
- Nadir reflectance spectroscopy
- Multiple depth spectroscopy
- Long-path spectroscopy
Dr Martin D. King
Wet geochemistry laboratory
In the wet geochemistry laboratory we are using the ICP-AES and ICP-MS technologies to analyse major and trace elements in geological and archaeological related materials.
- Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES)
ICP-AES is often the first method applied to quantitative analyses of solutions and solid samples. It can be used to determine major, minor, trace and rare earth multi-element compositions with a wide range of standard sample preparation procedures. Non-standard procedures and novel applications can also be accommodated.
- Inductively Coupled Plasma-Mass Spectrometry (ICP–MS)
ICP-MS is often the first method applied to quantitative analyses of solutions and solid samples. It can be used to determine minor, metal and trace multi-element compositions with a wide range of standard sample preparation procedures, including laser ablation. Non-standard procedures and novel applications can also be accommodated.
Analysis of Solutions
Ground- and surface-waters, landfill leachates, effluents and brines may be routinely analysed for: Ca, Na, K, Mg, Fe, Al, B, Ba, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, Sr, Ti, V, Y, and Zn, and in some cases, Si, S and P.
Analysis of Solids
Dissolution using a mixture of HF and HClO4 permits analysis of rocks, minerals, soils, sediments, glass, and ceramics for: Al2O3, Fe2O3, MgO, CaO, K2O, Na2O, MnO, P2O5, TiO2, Ba, Co, Cr, Cu, Li, Ni, Sc, Sr, V, Y, Zn and Zr. Semi-quantitative rare earth element data may also be obtainedFusion with LiBO2 provides complete analyses to determine SiO2, Al2O3, Fe2O3, MgO, CaO, K2O, Na2O, MnO, P2O5, TiO2, Ba, Sr, Y and Zr. Rare earth elements; La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb and Lu.
- River, lake and water borehole samples for heavy metals to assess water quality within former military and landfill sites.
- Arsenic in boreholes in Bangladesh.
For costs and information, please contact
Lab Manager: Dr Nathalie Grassineau
Lab Technician: James Brakely
Tel no. 01784 443633.
X-ray fluorescence laboratory
The laboratory houses a 2010 PANalytical Axios sequential X-ray fluorescence spectrometer with 4kW Rh-anode X-ray tube and a wide range of diffraction crystals. There is also a preparation laboratory for pellet-making and fusions. It is primarily focussed on deriving high-accuracy high-reproducibility major and trace element analyses on igneous, metamorphic and sedimentary rocks, of silicate, carbonate, phosphate or sulphate bulk composition. However, a wide variety of other materials may be analysed qualitatively, semi-quantitatively, or quantitatively if standards are available or provided by the user.
Elements analysed depend on the application and sample type. For example, our standard analyses for rock samples include:
Major elements (on fused glass discs using ~0.7g sample): SiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, K2O, TiO2, MnO, P2O5, Cr2O3, SO3, Cl, F (note that S and Cl may be volatilized during fusion)
Trace elements (on ~10g pressed pellets, requires major element analysis as well): Mo, Nb, Zr, Y, Sr, U, Rb, Th, Pb, Ga, Zn, W, Ta, Hf, Cu, Ni, Yb, Co, Sm, Cr, Ce, Nd, V, La, Ba, Cs, Sc, Sn, Cl, S, F. In addition, Fe2O3, CaO and TiO2 are analysed as cross-checks to the major element data.
We also provide scan-based semi-quantitative analysis of unknown samples using the PANalytical application Omnian, and trace element analysis of samples with no major element data using the PANalytical application ProTrace.
The laboratory is available for in-house, collaborative and commercial use, and costs depend on the type of analysis, the degree to which the user wants to be involved, and whether the work is collaborative or commercial.
Calibration ranges, typical precision and accuracy data
- Example calibration graphs
- Accuracy judged by comparison between XRF and isotope dilution data
- Example pellet and fusion reproducibility:
- Prof Matthew Thirlwall
- Dr Christina Manning
X-ray diffraction laboratory
There are several methods that can be used to identify a material, but one of the most common is that of X-ray diffraction (XRD). In this method, a small amount of the powdered material is placed on a glass slide, and exposed to a beam of X-rays. The resulting reflections and reinforcements of the X-rays at characteristic angles are then used to identify the unknown substance.
This method is especially useful for the characterisation of clay minerals, as various treatments (glycol, heat) change the XRD pattern and these changes can provide further information on the nature of the clay phase.
We use a Philips PW1830/3020 spectrometer and copper Kα X-rays. Mineral peaks can be identified manually or automatically from the ICDD Powder Diffraction File (PDF) database.
Quantitative analysis of mixtures to determine the exact proportions of different phases can be carried out using Rietveld analysis.