Calcium, Na, K and Mg Concentrations in Seawater by Inductively Coupled Plasma‐Atomic Emission Spectrometry: Applications to IAPSO Seawater Reference Material, Hydrothermal Fluids and Synthetic Seawater Solutions

Abstract

We report a measurement procedure to determine simultaneously the major cation concentrations (Na, Ca, K and Mg) of seawater-derived solutions by inductively coupled plasma-atomic emission spectrometry. The best results were obtained when the IAPSO ('standard') seawater reference material was diluted by thirty times with Milli-Q â water. We obtained an average reference value r K (the ratio of the mass fraction of potassium to that of chlorine, i.e., (g kg -1 )/(g kg -1 )) for IAPSO seawater of 0.0205 ± 0.0006 (2.9% RSD), not significantly different from 0.0206 ± 0.0005 (2.4% RSD) for seawater composition reported in the literature. The measured Na, Ca and Mg concentrations correspond to r Na , r Ca and r Mg values of 0.5406 ± 0.0026 (0.5% RSD), 0.02192 ± 0.00048 (2.2% RSD) and 0.06830 ± 0.00047 (0.7% RSD), respectively, in line with previous values measured by wet-chemistry and atomic absorption spectrophotometry or wet-chemical titration. Our measurement procedure was used successfully on synthetic seawater solutions and high-temperature hydrothermal fluids.Keywords: ICP-AES, IAPSO, reference material, major elements, seawater, hydrothermal fluids.Nous proposons une m ethode d'analyse par spectrom etrie d' emission coupl ee a un plasma induit pour mesurer simultan ement les concentrations en cation (Sodium, Calcium, Potassium et Magn esium) de solution d'eau de mer. Les meilleurs r esultats ont et e obtenus lorsque la solution de r ef erence d'eau de mer IAPSO etait dilu ee trente fois avec de l'eau Milli-Q â . Pour la solution de r ef erence IAPSO, nous obtenons une valeur moyenne pour r k (le rapport de la fraction massique de potassium sur celle de chlore, c. a.d. (g kg -1 )/(g kg -1 )) egale a 0.0205 ± 0.0006 (2.9% RSD). Cette valeur est similaire a 0.0205 ± 0.0005 (2.4% RSD) de la composition de l'eau de mer mentionn ee dans la litt erature. Les concentrations mesur ees pour le Na, Ca et Mg correspondent a un r Na de 0.5406 ± 0.0026 (0.5% RSD), un r Ca de 0.02192 ± 0.00048 (2.2% RSD) et un r Mg de 0.06830 ± 0.00047 (0.7% RSD). Ces valeurs sont en ad equation avec celles mesur ees au pr ealable par chimie humide et spectrophotom etrie d'absorption atomique ou par titrage chimique par voie humide. Nous avons utilis e notre m ethode d'analyse pour d eterminer la composition chimique d'eau de mer synth etique et de fluides hydrothermaux de haute temp erature.Mots-clés : ICP-AES, IAPSO, mat eriaux de r ef erence, el ements principaux, eau de mer, fluides hydrothermaux.

Sulfate minerals control dissolved rare earth element flux and Nd isotope signature of buoyant hydrothermal plume (EMSO-Azores, 37°N Mid-Atlantic Ridge)

“…The analytical methods used for major and trace element concentrations in hydrothermal fluid and plume were described in details in previous publications (Besson et al, 2014;Cotte et al, 2015;Leleu, 2017;Waeles et al, 2017).…”

On the early fate of hydrothermal iron at deep‐sea vents: A reassessment after in situ filtration

“…Chemical analyses were conducted at the Geosciences Environment Toulouse laboratory with an inductively coupled plasma-atomic emission spectrometer (ICP-AES; Horiba Ultima2) [Besson et al, 2014]. At each dive, four gas-tight titanium syringes were triggered per smoker, and time delay between each sampling replicate did not exceed 20 min.…”

“…H 2 S concentrations were measured in the solution with an amperometric microsensor (AquaMS, France). Chemical analyses were conducted at the Geosciences Environment Toulouse laboratory with an inductively coupled plasma-atomic emission spectrometer (ICP-AES; Horiba Ultima2) [Besson et al, 2014]. The instrument is calibrated using monoelemental solutions, multielemental solution, and International Association for the Physical Sciences of the Oceans standard solution.…”

Prokaryote Communities at Active Chimney andIn SituColonization Devices After a Magmatic Degassing Event (37°N MAR, EMSO‐Azores Deep‐Sea Observatory)

“…The major and trace elements concentrations (Si, Ca, Na, K, Mg, Sr, Fe, and Mn) were measured by inductively coupled plasma optical emission spectrometry (Horiba Jobin Yvon Ultima 2), which was calibrated using seawater IAPSO standard (OISIL Limited, UK) a synthetic matrix-match standards following the measurement protocol of Besson et al (2014). All the hydrothermal fluid samples were clear, void of visible particles, and not acidified during storage.…”