Flame or Graphite Furnace Atomic Absorption Spectrometer to analyze cation concentrations (Al, As, Ba, Ca, Cr, Co, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Pt, Sb, Sn, Sr, Zn)

Description of the instrument

The Atomic Absorption Spectrometer (Agilent Technologies AAS 240 FS and GTA 120) can measure the concentrations of many elements. Depending on the concentrations of the solutions, it can be used in flame mode or in graphite furnace mode. It is equipped with automatic diluters (flame/oven) and autosamplers (flame/oven).

Principle of analysis

A liquid sample is injected as a mist into a flame (in flame mode) or a drop is placed in a graphite furnace (in graphite furnace mode). The heat vaporizes the elements contained in the sample and excites their atoms. These disrupt a light signal by reducing its intensity (absorption) or by emitting photons (emission). The light emitted by a hollow cathode lamp(s) or by the electrons of the excited atoms is sent via a set of mirrors and a crystal lattice to a detector which performs an optical measurement of the signal compared to a signal of undisturbed reference. The difference in light intensity is proportional to the concentration of the element in the solution. Calibration is done by injecting a standard solution to obtain the appropriate range. See principle of measurement here: http://spin.mines-stetienne.fr/sites/default/files/specatom.pdf

Analyzes carried out on the instrument

• Major cations (Ca, Mg, Na and K) between 0.05 and 100 ppm in flame with an accuracy of +/- 5%;
• Metals (Al, As, Ba, Cr, Co, Cu, Fe, Li, Mn, Mo, Ni, Pb, Pt, Sb, Sn, Sr, Zn) between 0.01 and 1000 ppm in flame depending on the elements and a few tens of ppt to a few tens of ppb in graphite furnace mode for some elements with an accuracy of +/- 5%;
• Only liquid solutions (filtered and acidified) are analyzed but it is possible to measure solutions of acid attack on rocks, sediments or other solid samples.

Contacts

Gaël Monvoisin : + 33 (0)1.69.15.71.74 / gael.monvoisin@universite-paris-saclay.fr

Fundings

CNRS – INSU / University Paris-Sud : AAS flame Year 2010 – AAS graphite furnace Year 2012

Description of the instrument:

Nier source mass spectrometer equipped with a Faraday double-cup detector enabling the simultaneous collection of ⁴⁰Ar and ³⁶Ar. The mass spectrometer is designed for high-precision measurements of Argon isotopes in terrestrial and extraterrestrial samples. The mass-spectrometer is coupled to an automated gas purification line and equipped with GP10 and GP50 getters, a titanium sublimator pump, ensuring gas purification and low procedural blanks. The extraction of the gases from the samples is achieved by an induction furnace This spectrometer and the connected extraction line are dedicated to the exclusive measurement of the isotopes of the Argon.

Principle of analysis:

https://w3.lsce.ipsl.fr/Phocea/Vie_des_labos/Ast/ast_sstechnique.php?id_ast=55

Analysis achieved by the instrument:

⁴⁰K/⁴⁰Ar datings on groundmass (lavas) and Illites.

Contacts:

H.Guillou (herve.guillou[a]lsce.ipsl.fr)

V. Scao (vincent.scao[a]lsce.ipsl.fr)

S. Nomade (sébastien.nomade[a]lsce.ipsl.fr)

Description of the instrument:

Nier source mass-spectrometer equipped with a Faraday cup-type detector and an electron multiplier and ion counter for high-sensitivity measurements of all noble gases (He, Ne, Ar, Kr and Xe). It is designed for high-precision measurements of rare gases in terrestrial and extraterrestrial samples. The mass-spectrometer is coupled to an automated gas extraction and purification line and equipped with 4 getters (2 GP10 and 2 GP50 operating at hot) to ensure that the gas introduced into the spectrometer is clean and free of active gas. The extraction of the gases from the samples is done either with a double-walled furnace cooled with water or with a C02 laser. This mass spectrometer and the preparation line are dedicated to the exclusive measurement of Argon isotopes.

Principle of Analysis:

https://w3.lsce.ipsl.fr/Phocea/Vie_des_labos/Ast/ast_sstechnique.php?id_ast=55

Analysis achieved by the instrument:

⁴⁰Ar / ³⁹Ar dating of groundmass splits (Lavas)via step-heating experiments and 40Ar / 39Ar laser dating on single crystal (Potassic Feldspar, Micas, Amphiboles).

Contacts:

S. Nomade (sébastien.nomade[a]lsce.ipsl.fr)

V. Scao (vincent.scao[a]lsce.ipsl.fr)

H.Guillou (herve.guillou[a]lsce.ipsl.fr)

Description of the instrument:

180° Mass Spectrometer and its line for extraction (HF furnas and CO2 laser) and purification of Argon for 40Ar/39Ar dating by simultaneous collection.

Principle of analysis:

http://geochrono.free.fr/fr/tech/chronk/arar/principe/ararprin.html

Analyses achieved on the instrument:

Mesurement of the isotopic composition of Argon (masses 36, 37, 38, 39 et 40) through step-heating approach (HF furnace) or laser fusion for 40Ar/39Ar dating on mineral populations.

More details in : Coulié, E., X. Quidelleur, J.C. Lefèvre and P.Y. Gillot, 2004. Exploring the multicollection approach for the 40Ar/39Ar dating technique. Geochem. Geophys. Geosyst., 5 (11) : 2004GC000773.

Contacts:

Anthony Hildenbrand : 01.69.15.67.42 - anthony.hildenbrand[a]universite-paris-saclay.fr

Xavier Quidelleur : 01.69.15.48.87 - xavier.quidelleur[a]universite-paris-saclay.fr

Description of the instrument:

180 ° Mass spectrometer 180° and its line for argon extraction (HF furnace) and purification for K/Ar dating with the Cassignol-Gillot technique

Principle of the analysis:

http://geochrono.free.fr/fr/tech/chronk/KAr/principe/karprin.html

Type of analyses achieved with the instrument:

Measurement of the Argon isotopic composition (masses 36 and 40), determination of the radiogenic argon yield for dating with the K/Ar Cassignol-Gillot technique.

More details in: Gillot, P.Y., Hildenbrand, A., Lefèvre, J.C., and C. Albore-Livadie, 2006. The K/Ar dating method : principle, analytical techniques, and application to Holocene volcanic eruptions in Southern Italy. Acta Vulcanologica, 18 : 55-66.

Contacts:

Anthony Hildenbrand : 01.69.15.67.42 - anthony.hildenbrand@universite-paris-saclay.fr

Xavier Quidelleur : 01.69.15.48.87 - xavier.quidelleur[a]universite-paris-saclay.frxavier.quidelleur[a]universite-paris-saclay.fr

Description of the instrument:

Spectrophotometer to measure potassium concentration by atomic absorption for K/Ar dating with the Cassignol-Gillot technique

Principle of analysis:

Measurement of the K-content in rocks and natural minerals (after acid attack) by flame spectrophotometry.

http://geochrono.free.fr/fr/tech/chronk/KAr/principe/karprin.html

Analyses achieved on the instrument:

Measurement of the K content for K/Ar dating with the Cassignol-Gillot technique.

Contacts:

Anthony Hildenbrand : 01.69.15.67.42 - anthony.hildenbrand[a]universite-paris-saclay.fr

Xavier Quidelleur : 01.69.15.48.87 - xavier.quidelleur[a]universite-paris-saclay.fr

MC-ICPMS Neptune^Plus Thermofisher Scientific

MC-ICPMS Neptune Plus (2010)		Laser ESI –NWR 193 nm (2011)

Characteristics of Instrumentation:

The MC-ICPMS Neptune^Plus is a mass spectrometer (MS) with a source of Argon plasma (ICP), a dual focusing (electrostatic field + magnetic field) and a multi-collection (MC). This mass spectrometer allows the precise measurement of stable, radiogenic or radioactive isotopes for many chemical elements of the Periodic Table in natural archives (waters, carbonates, apatites, sediments, soils, rocks, etc.). The high ionization efficiency of the Plasma source gives it a great sensitivity. Its dual focusing ensures good transmission of the ion beam and offers us the ability to work at low, medium or high resolution (suppression of some isobaric interferences). Finally, the high stability of multi-collection provides an excellent analytical accuracy on isotopic ratios (external reproducibility ranging from a few tens of ppm to sub- ‰). Another advantage is that the plasma source, opened to the atmosphere, allows us to introduce and analyze samples in liquid form after chemistry (micro-nebulizers, desolvating systems) or directly on solids (Ablation Laser coupling). Main fields of application are geochronology (U-Th dating), marine geochemistry and paleoceanography (Pa, Th, U, Ra, Nd isotopes), carbon cycle in ocean and the impact of ocean acidification (B, Th, Si isotopes), isotopic characterization of volcanic or sedimentary rocks or some developments in archeology (Nd, Sr, Pb or even Cu, Zn, Fe Isotopes).

Principle of Measurement:

In solution, the sample is aspirated and injected by a spray nebulizer into a "Plasma" source of argon at 6000-8000°K and atmospheric pressure. At this high temperature, the elements are ionized. Transferred by an interface (sampler and skimmer cones), the ions are accelerated under primary and then secondary vacuum to form an ion beam with a final energy of up to 10 keV. The beam is filtered in energy (electrostatic sector), then in mass (magnetic sector) according to the ratio m/z. The isotopes are detected by a multi-collector system with 15 detectors (9 Faraday cages, 1 SEM and 5 CDD). The isotopes and ratios are then measured and calculated at high precision simultaneously on several detectors. Obtained external reproducibilities are of a few tens of ppm for the isotopes of Sr, Nd, from 0.05 to a few 0.1 ‰ for Li, B isotopes or of the order of 1 ‰ for systems with low isotopic ratios (U and Th isotopes). The central cage ion beam can switch over to the central ion counter (SEM) if the signal is too low, making it possible, for example, to measure the isotopes ²³⁰Th and ²³⁴U, isotopes essential for U-Th dating. For few isotopic systems (Si, Fe or more generally transition metals), measurements are carried out in medium or high resolution in order to separate the analyzed isotopes from potential isobaric interferences. In such configuration, signal intensity is decreased but resolving power can be increased by 10-fold.

MC-ICPMS isotopic measurements are relative and require laboratory or international standards or reference materials whose isotopic values ​​are known and / or certified (NIST). The “bracketing” protocol is generally used to characterize precisely the isotopic composition of a studied element and to take into account the instrumental drifts. It is possible to introduce into the plasma source solutions previously purified in a clean room but also a flow of helium gas which entails aerosols. Thus, isotopic measurements of some elements such as Sr, B or U in carbonates are performed after coupling with the laser ablation system Excimer NWR193 nm.

Others information

• Nebulizers PFA 20, 50 ou 100 µL/min & micro-cyclonic chamber (solutions)
  
• Desolvating inlet system APEX Omega and Omega HF & ARIDUS II + QuickWash (2 to 10 -fold sensitivity increase, solutions)
  
• Jet-Interface installed in 2014 (reinforced sensitivity: from 2 to 5-fold, solutions)
  
• Ablation laser Excimer ESI – NWR 193 nm (in-situ analysis, aerosols from solid materials)

Isotopic measurements performed by MC-ICPMS:

Solutions (after chemistry)

• U, Th, Pa, Ra: U-series Geochronology, marine or continental Geochemistry ;
• Sr, Nd and recently Pb for various natural materials: source determination, erosion, ocean circulation and dynamics, archeological studies ;
• B and Li for carbonates or waters: paleo-pH and ocean acidification (carbon cycle), marine biogeochemistry ;
• Other systems: Si, Fe, Cu, Zn, etc.

Solid matrix per Ablation laser (development in progress)

• B (δ¹¹B), of Sr (⁸⁷Sr/⁸⁶Sr) and U (δ²³⁴U) in carbonates or silicates.

Contacts:

Instrumental responsible

Arnaud Dapoigny arnaud.dapoigny[a]lsce.ipsl.fr 01 69 08 04 70

Main Scientist responsible

Dr Eric Douville (B, Li, Sr) eric.douville[a]lsce.ipsl.fr 01 69 08 22 57

Other GEOPS-LSCE scientists involved:

Dr Christophe Colin (Nd, Sr), Dr Edwige Pons-Branchu (U, Th, Ra, Sr, Pb), Claire Rollion-Bard & François Thil (Laser), William Gray (B), Damien Guinoiseau (Pb).

Inductively Coupled Plasma – Quadrupole Mass Spectrometer - ICP-QMS X-series^II CCT

Characteristics of Instrumentation:

The Inductively Coupled Plasma – Quadrupole Mass Spectrometer (ICP-QMS) X-series II CCT Thermo Fisher Scientific is dedicated to quantitative multi-element analysis. This instrument allows rapid (~ minute), precise (~ percent) and quasi-simultaneous determination of the content of many chemical elements of the Periodic Table from the majors to those present in trace amounts in natural samples (freshwater, seawater, plants, soils, carbonates, apatites, rocks, etc.) or for any other type of materials or solutions. In its basic configuration, this mass spectrometer offers detection limits lower than μg / L (ppb) for many elements in solution and can reach several 100 pg / L (ppq) for heavy elements such as Rare Earth Elements or Uranium. Two options improve its performance: i- the CCT collision cell eliminates polyatomic interferences, typically for elementary analysis with atomic mass between 40 and 80 (transition metals, metalloids such as As, Se) ; ii- an additional pumping called “option S” at the interface lowering the detection limit for some heavy elements (uranium) to a few pg / L.

Three major application domains are currently being developed at the LSCE: i- elementary or isotopic (Pb) characterization of samples dissolved in solution to trace erosion processes, study of particle mobility as well as determine their origins, and quantitatively monitor the dissemination of some heavy or toxic metals in the environment, particularly in urban environments ; ii- elementary characterization of marine or continental carbonates/apatite archives (corals, foraminifera, speleothems, teeth, etc.) for paleoceanography, climatology or archeological studies (marine geochemistry, ocean temperature, carbon cycle and ocean acidification, precipitation, etc.) ; and iii- U-series Geochronology and U-Th dating of carbonates (corals) or apatites (teeth).

Principle of Measurement:

The principle is based on dissociation of molecules, atomization and ionization of the elements present in a solution and injected into a "Plasma" source of argon at 6000-8000 °K and atmospheric pressure. After the formation of an ion beam via the interface (sampler and skimmer cones) during a progressive transition to a secondary vacuum, a Quadrupole separates the isotopes or ions at low resolution according the m/z ratio. The ions/isotopes are then detected by a discrete-dynode electron multiplier. The precise quantification of the contents of major and / or trace elements is obtained after calibration of the instrumentation (standard solutions known or certified). Depending on the matrix or nature of the samples analyzed, the elements studied and the degree of precision sought, different calibration methods are used (standard calibration curves, standard addition or matrix recomposition methods, “bracketing” approach).

Other informations

• Nebulizers : PFA 20, 50 or 100 µL/min ; quartz 1 mL/mn (solutions);
• Quartz micro-cyclonic spray chamber or conic chamber with impact bead (solutions);
• Desolvating systems APEX HF (2 à 10-fold more sensitive, solutions) ;
• Ablation laser Excimer ESI – NWR 193 nm (in-situ analysis, aerosols from solid materials).

Measurements performed by ICP-QMS:

• Quantification of major and/or trace elements in waters, soils, rocks, carbonates (erosion / transfer of particles) ;

• Relative measurement of Pb isotopes (source tracing) ;

• Quantification of majors (Sr/Ca, Mg/Ca) and trace elements (Li/Mg; B/Ca; Ba/Ca, U/Ca, REE, etc.) present in carbonates like corals or speleothems (paleoceanography / climatology / carbon cycle) ;

• Quantification of rare earths and other elements present as ultra-traces in seawater or sediments (characterization of materials or processes) ;

• Relative measurement of U and Th isotopes for U-Th dating of corals, speleothems, teeth.

Contacts:

Delphine Thomas : delphine.thomas[a]lsce.ipsl.fr    01 69 08 33 77

Sophie Ayrault : sophie.ayrault[a]lsce.ipsl.fr   01 69 08 40 71

Eric Douville : eric.douville[a]lsce.ipsl.fr       01 69 08 22 57

Instrument description:

Cryogenic magnetometer equiped with three high homogeneity pick-up coils. The magnetometer is placed within the µmetal shielded room.

Principle of the analysis:

Cryogenic magnetometer measuring at once the three components X, Y and Z of the remanent magnetization (Natural Remanent Magnetization (NRM), Anhysteretic Remanent Magnetization (ARM), Isothermal Remanent Magnetization (IRM)) carried by standard size sample (25 mm x max 22 mm for cylinders, 22 mm side for cubes). The magnetometer is placed within the µmetal shielded room. See the description of zero-field furnaces and of alternating field demagnetization for the associated demagnetization modes.

Analyses performed with the instrument:

All remanent magnetizations (natural, anhysteretic, isothermal) on standard sedimen, archaeological baked clays and lava samples.

Contacts:

Gwenaël Hervé : 01.69.08.02.48 / gwenael.herve[a]lsce.ipsl.fr

Instrument description:

Bartington coil MS2C (22mm diameter; spatial resolution: 4.5 cm)

Analyses performed with the instrument:

Low-field magnetic susceptibility

Adapted for sediments sampled with u-channels

Contact:

Gwenaël Hervé : 01.69.08.02.48 / gwenael.herve[a]lsce.ipsl.fr