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Two stalagmites from B7-Cave in northwest Germany, which is part of the same cave system as the intensively studied Bunker Cave, were re-dated by multi collector inductively coupled plasma mass spectrometry (MC-ICPMS) 230Th/U-dating. Furthermore, the concentration of Mg, Sr, Ba, P, Y, Zn, and Al were determined at high-resolution by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Stalagmite B7-1 grew from 10.8 to 5.8 ka BP. Stalagmite B7-7 grew during three growth phases from 11.0 to 6.2, 3.13 to 2.86 (late Bronze Age), and 1.27 to 1.15 ka BP (early Medieval Period). Aluminium is a proxy for detrital material and corresponds very well with the visible detrital layers in stalagmite B7-1 and the oldest growth phase of stalagmite B7-7. The two younger growth phases of stalagmite B7-7 are very clean and show very low Al concentrations. Phosphorus, Y, and Zn show positive correlations in both stalagmites and all growth phases, but do not show a relationship to temperature or precipitation. This may be related to the elevated detrital content in both stalagmites. Barium and Sr also show a positive correlation in both stalagmites and all growth phases, which is related to their dependency on growth rate. Magnesium is most probably influenced by prior calcite precipitation and therefore a proxy for past precipitation/infiltration. The Mg records of stalagmite B7-1 and of the oldest growth phase of stalagmite B7-7 show decreasing Mg concentration with time reflecting decreasing prior calcite precipitation and therefore increasing precipitation during the Early to Mid-Holocene. This is consistent with other climate reconstructions from Central Europe. [ABSTRACT FROM AUTHOR]

Homogeneity, mass fractions of about forty trace elements and Sr isotope composition of Ca carbonate reference materials (RMs) between original and nano‐powdered pellets are compared. Our results using nanosecond and femtosecond LA‐(MC)‐ICP‐MS show that the nano‐pellets of the RMs MACS‐3NP, JCp‐1NP and JCt‐1NP are about a factor of 2–3 more homogeneous than the original samples MACS‐3, JCp‐1 and JCt‐1, and are therefore much more suitable for microanalytical purposes. With the exception of Si, the mass fractions of the synthetic RM MACS‐3 agree with its fine‐grained analogue MACS‐3NP. Very small, but significant, differences between original and nano‐pellets are observed in the RMs JCp‐1 and JCt‐1 for some trace elements with very low contents, indicating the need for re‐certification. Strontium mass fractions in the analysed RMs are high (1500–7000 mg kg−1), and their isotope compositions determined by LA‐MC‐ICP‐MS in the original and the nano‐pellets agree within uncertainty limits. [ABSTRACT FROM AUTHOR]

We investigated rock varnish formed on sandstone and petroglyphs in the Hima area, southwestern Saudi Arabia. To characterize the rock varnish, we made in-situ measurements by portable x-ray fluorescence (pXRF) and analyzed samples by femtosecond laser-ablation inductively coupled–plasma mass spectrometry (fs LA-ICP-MS). Detailed chemical analysis of the rock varnish samples and adjacent soil or aeolian dust yielded information about the varnish's geochemical context and formation mechanism. Untypically low positive Ce anomalies in the rock varnish samples correlated with negative Ce anomalies in the dust, supporting the hypothesis that the dust is the source of the varnish material. To study the varnish development, we made use of the fact that engraving the petroglyphs exposes a fresh bare sandstone surface without varnish, on which varnish regrows subsequently. We determined by pXRF the areal density of manganese (Mn) and iron (Fe) that had been deposited as rock varnish since the creation of the rock art. The rates of Mn deposition in the newly formed varnish were then estimated by correlating the areal density of Mn in Ancient Arabian and Old Arabic inscriptions with their known age ranges. The observed deposition rates showed substantial variability resulting from differences in exposure conditions of the rock surface, but were in a range comparable with that of our previous measurements in northwestern Arabia. This variability could be reduced significantly by referencing the measurements to the intact varnish adjacent to the individual petroglyphs. This normalization provided a much clearer relationship between varnish deposition and age, and enabled tentative ages to be assigned to rock art motifs without previously known ages. These tentative ages spanned most of the Holocene period and were consistent with the culturally or ecologically derived ages of the animal and human figures depicted in the rock art and the styles of scripts used in different periods. [ABSTRACT FROM AUTHOR]

Precise and accurate determination of major components in alkali silicate glasses provides critical information concerning element distribution, petrogenesis and magmatic evolution. However, as one of the most important in situ microanalytical technologies, the application of electron probe microanalysis (EPMA) was limited by the time-dependent loss of X-ray intensity of alkali ions (especially Na) during electron beam bombardment on alkali silicate glasses. In this study, an optimized analytical method was developed using a JEOL JXA 8100 EPMA, aiming to get a long enough incubation duration suitable for accurate analysis of major element mass fractions. The optimal analytical conditions were determined as follows: 15 kV accelerating voltage, 2 nA beam current, 20 μm beam diameter, 40 s peak counting time, Na and K analyzed with top priority, time-saving mode with no additional detector movement and no peak search functioned. The availability of this low beam current density condition (6.37 × 10−3 nA μm−2) to 24 anhydrous reference glasses, with their compositions covering the entire spectrum from the ultramafic to highly siliceous range, was verified by the good agreement of the EPMA measured data with their GeoReM preferred values. Similarly, the methodology presented here is also suitable for analysis of hydrous glasses with H2O contents up to approximately 9 wt%, accompanied by no obvious Na loss found and no complicated mathematical corrections needed, and therefore can be used for the estimation of H2O contents in H2O-rich (>1 wt%) geological glasses by the difference method. Despite its analytical accuracy and precision (>0.5 wt%) not better than those of SIMS and FTIR, EPMA can be used as a substitute technique for H2O determination with its main advantages of excellent spatial resolution (down to 5–10 μm) and analytical convenience, especially for small melt inclusions or tiny experimental quench products, and the case with no appropriate calibration standards or no reported extinction coefficients available for those compositions of interest. In daily application, our optimized method is low cost and easy to implement and can achieve comparable precision and detection limits with acceptable efficiency (∼4–5 min/point for ten major elements) relative to routine analysis conditions. [ABSTRACT FROM AUTHOR]

Manganese- and iron-rich materials are of major geoscientific and economic interest, many of which contain microscopic features that provide valuable information. To obtain accurate results, a homogeneous microanalytical reference material for calibration is needed. Several researchers have used the Mn- and Fe-rich RMs, JMn-1, NOD-A-1, NOD-P-1 and FeMn-1, for this purpose; therefore, they were tested in this study to determine their suitability for microanalysis. Their homogeneity was investigated by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) with two different types of lasers (nano- and femtosecond), with spot and line scan analyses and with different operating parameters, such as spot size, pulse repetition rate and fluence. As the established manganese nodule RMs revealed inhomogeneities for picogram to microgram test portions, we also investigated the new synthetic Fe- and Mn-rich RM, FeMnOx-1. FeMnOx-1 was found to be homogeneous for large (ø 40 μm: 2% RSD repeatability) and small (ø 8-10 μm: 10% RSD repeatability) spot sizes. This homogeneity is in the range of the homogeneous NIST SRM 610 and GSE-1G reference glasses. Furthermore, FeMnOx-1 revealed a large-scale homogeneity within uncertainties of a few per cent, using test portions in the ng range, when measuring four individual mounts of this material. [ABSTRACT FROM AUTHOR]

We present new reference values for nineteen USGS, GSJ and GIT-IWG rock reference materials that belong to the most accessed samples of the GeoReM database. The determination of the reference values and their uncertainties at the 95% confidence level follows as closely as possible ISO guidelines and the Certification Protocol of the International Association of Geoanalysts. We used analytical data obtained by the state-of-the-art techniques published mainly in the last 20 years and available in GeoReM. The data are grouped into four categories of different levels of metrological confidence, starting with isotope dilution mass spectrometry as a primary method. Data quality was checked by careful investigation of analytical procedures and by the application of the Horwitz function. As a result, we assign a new and more reliable set of reference values and respective uncertainties for major, minor and a large group of trace elements of the nineteen investigated rock reference materials. [ABSTRACT FROM AUTHOR]

We applied three different LA systems (213 nm nanosecond solid state, 193 nm nanosecond excimer, and 200 nm femtosecond laser) coupled to a quadrupole ICP-MS or a sector field ICP-MS, respectively, for the analysis of different sulfide minerals (pyrrhotite, chalcopyrite, and sphalerite). Ablation craters were investigated via back-scattered electron (BSE) images to compare the amounts of melt produced, and fractionation factors were calculated to determine the degree of down-hole fractionation. Our results show significant differences in melting between the three LA systems. While samples show massive melting when using the ns systems, no melting has been observed utilizing the fs laser. Fractionation factors for a variety of elemental pairs indicate the absence of down-hole fractionation even at the highest melt production. The extent of melting of different sulfide specimens is independent of melting temperatures of these materials. Although no down-hole fractionation has been observed, Fe/S fractionation as calculated from sensitivities deviate among pyrrhotite and chalcopyrite when applying the 193 nm ns and 200 nm fs systems. Analyses of synthetic pyrrhotite with known PGE concentrations using the 200 nm fs LA system yielded moderately precise and accurate concentration data (3–4%; 4–14% 2SD) utilizing sulfide as the external reference material. Application of NIST610 as the reference material improved the precision to 1.4–2.4% 2SD and the deviation from reference values to 5–7%. [ABSTRACT FROM AUTHOR]

Diagenetic alternation of apatite building vertebrate bioclasts is a complex process. It is influenced by numerous factors, but the impact of diagenetic processes affecting the host rock is commonly underestimated. The present study aims at identifying the causes of different concentration levels and distribution patterns of REE, and at examining the significance of the material chosen for normalisation. We measured REE and other trace element concentrations in three bone assemblages of Triassic marine reptiles using LA-ICP-MS, and in the host rocks using ICP-MS. Two groups of hard parts reveal clearly different trace element contents and distribution patterns. The remains from Gogolin show a distinct MREE N enrichment, which must have been caused by replacement involving numerous substitutions, that was possible due to a relatively high porosity of the host rocks, and the presence of pore water. The MREE N enrichment and low concentrations of Mg and Sr, combined with a relatively high content of U in these bones, indicate solutions derived from meteoric water as the source of the incorporated ions. The reductive dissolution of Fe oxyhydroxides that are abundant in the host rock matrix and that likely were an important source of REE, may have influenced and controlled the REE uptake. The significant HREE N enrichment over LREE N , as revealed in the rust-coloured bones from Raciborowice Górne, is likely connected with local acidification of the pore water, resulting from aqueous oxidation of pyrite, infilling the pore spaces in the bones. The material selected for normalisation of the chemical composition of apatite can have a significant impact on values of the normalised data used further for interpretations, particularly when vertebrate bioclasts from carbonate host rocks are involved. The carbonate rocks have element ratios that differ from those characterising the commonly used PAAS and NASC normalisation materials. In particular, Ce anomaly values can distinctly vary depending on the applied normalisation procedure. Vertebrate hard parts, that definitely spent more time in a host rock than in an animal body, must be rigidly handled as a constituent of a specific rock, never as a separate item. [ABSTRACT FROM AUTHOR]

Atmospheric dust has a substantial impact on climate, and climate in turn affects the dust flux and origin. Knowing its composition helps to determine dust sources and climate processes. We have therefore determined 46 major and trace elements in dust samples, using in-situ 200 nm-femtosecond laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Very small test portions of 4–7 μg were enough to enable analyses down to detection limits of femtograms and ng g − 1 , respectively. The data agree within 40 to 15% with the reference values for test portions of 1 to 100 μg, respectively. The femtosecond laser results are compared to those obtained using a 213 nm nanosecond laser, which show the advantages of the femtosecond laser, such as the ability to use non-matrix-matched calibration, reliable measurements of volatile elements, and smaller quantities of material ablation with similar results for the repeatability. The technique is especially useful for measurements of small amounts of dust on filters, and for 2D-distribution maps of selected elements to identify minerals or contamination. To demonstrate the applicability, five dust samples from Niger and Chad, in the Sahara zone, were analyzed. The samples are characterized by enrichment in light REEs and a distinct Eu anomaly, with surface soils as their source. [ABSTRACT FROM AUTHOR]

LA- ICP- MS is one of the most promising techniques for in situ analysis of geological and environmental samples. However, there are some limitations with respect to measurement accuracy, in particular for volatile and siderophile/chalcophile elements, when using non-matrix-matched calibration. We therefore investigated matrix-related effects with a new 200 nm femtosecond (fs) laser ablation system ( NWRFemto200) using reference materials with different matrices and spot sizes from 10 to 55 μm. We also performed similar experiments with two nanosecond (ns) lasers, a 193 nm excimer ( ESI NWR 193) and a 213 nm Nd: YAG ( NWR UP-213) laser. The ion intensity of the 200 nm fs laser ablation was much lower than that of the 213 nm Nd: YAG laser, because the ablation rate was a factor of about 30 lower. Our experiments did not show significant matrix dependency with the 200 nm fs laser. Therefore, a non-matrix-matched calibration for the multi-element analysis of quite different matrices could be performed. This is demonstrated with analytical results from twenty-two international synthetic silicate glass, geological glass, mineral, phosphate and carbonate reference materials. Calibration was performed with the certified NIST SRM 610 glass, exclusively. Within overall analytical uncertainties, the 200 nm fs LA- ICP- MS data agreed with available reference values. [ABSTRACT FROM AUTHOR]

Abstract: Ostracod shells, belonging to three taxa (Leucocytherella sinensis Huang, 1982, ?Leucocythere dorsotuberosa Huang, 1982 and ?L. dorsotuberosa f. postilirata sensu Pang, 1985), were collected from two sediment cores from Lake Nam Co, on the central Tibetan Plateau. Two variants of LA–ICP–MS (laser ablation–inductively coupled plasma–mass spectrometry), spot and line-scan analyses, were used to investigate trace element concentrations (Mg, Sr, Ba, U and rare earth elements [REEs]) in single ostracod shells. The results suggest that the line-scan method can provide better precision than the spot analysis and is therefore preferred. No significant difference in trace element composition between taxa was detected in our study. Fluctuations of Mg/Ca and Sr/Ca in the shells show good agreement with the reported lake level changes during the Holocene, indicating that ostracod Mg and Sr can be related to palaeohydrochemical processes in this area. A high correlation between Ba/Ca and Sr/Ca was detected in our study, perhaps implying that both metals were controlled by the same mechanisms. A possible relationship between ostracod U/Ca and the past redox conditions on the lake bottom is discussed. Relatively low and constant La/Ca was observed, which could be due to the REE characteristics in the lake water, or ostracod biological processes, or even the associated Fe–Mn and/or organic contaminants. Future studies on more specimens from this area, especially shells from living ostracods, are essential to investigate the potential of ostracod Ba, U and REEs for use as palaeoenvironmental indicators. [Copyright &y& Elsevier]

Abstract: The rare earth elements (REE) contained in fossil bones are widely used for provenance and palaeoenvironmental studies. Earlier works suggested that the REE uptake is limited to early diagenesis, but more recent research provided evidence of long-term open-system diffusion in fossil bones. We analysed thin-walled reptile bones, all collected from the same Middle Triassic (~245Ma) marine bonebed, comprising vertebrate remains of likely different ages, to check the influence of the long-term diagenesis on the concentrations of REE, in terms of impact of pore water; the upper parts of the bones are contained in a low-permeability crinoidal limestone, whereas their lower parts have been affected by diagenetic fluids for a long time. We measured REE and other trace element contents in 29 bones using LA-ICP-MS (totally 660 spots in 45 depth profiles). Neither the absolute concentrations of the REE and the REE intra-bone PAAS-normalised patterns, nor the inter-element ratios and the La, Ce and Eu anomalies appear useful to distinguish between the likely older and younger bones in the bonebed. The MREEN enrichment combined with the flat intra-bone distributions of the REE lead to conclusion that REE fractionation and substitution for Ca were the most important processes responsible for the selective uptake. The low-permeability host rock and diagenetic fluids had a significant impact on the trace element uptake and their intra-bone distribution patterns. The lower parts of the bones that likely had a long-lasting contact with the diagenetic fluids reveal a relative enrichment in the REE and their easier diffusion into the bone centres. The ability of fossil bones to incorporate trace elements over a long time-span strongly limits the usage of particularly the older samples for provenance and palaeoenvironmental reconstructions. Additionally, the presented new analyses fill the gap between the available databases of trace element concentrations in fossil bones with regard to Middle Triassic samples. [Copyright &y& Elsevier]

To test whether the silicate reference glasses BAM-S005-A and BAM-S005-B from BAM (The Federal Institute for Materials Research and Testing, Germany) are suitable materials for microanalysis, we investigated the homogeneity of these reference glasses using the microanalytical techniques EPMA, LA-ICP-MS and SIMS. Our study indicated that all major and most trace elements are homogeneously distributed at micrometre sampling scale in both types of glass. However, some trace elements (e.g., Cs, Cl, Cr, Mo and Ni) seem to be inhomogeneously distributed. We also determined the composition of BAM-S005-A and BAM-S005-B. The EPMA data of major elements confirmed the information values specified by the certificate. With the exception of Sr, Ba, Ce and Pb, our trace element data by LA-ICP-MS were also in agreement with the certified values within the stated uncertainty limits. The reasons for the discrepancy in these four elements are still unclear. In addition, we report new data for twenty-two further trace elements, for which the concentrations were not certified. Based on our investigation, we suggest that both of these materials are suitable for many microanalytical applications. [ABSTRACT FROM AUTHOR]

Abstract: The high spatial resolution of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) microanalysis of speleothems and biogenic calcium carbonates makes it possible to improve our understanding of past climatic conditions. However, there are analytical problems associated with this method, such as molecular interferences, elemental fractionation, and mass-load-dependent matrix effects, when using NIST silicate reference glasses for calibration. Our study with a sector-field ICP-MS shows that many masses are affected by interferences, such as 24Mg+ by 48Ca++ or 31P+ by 15N16O+. Elemental fractionation and mass-load-dependent matrix effects have been detected for both 213 and 193nm Nd:YAG lasers. They are small for refractory lithophile elements, in particular for the 193nm laser (<5%). For chalcophile/siderophile trace elements with low boiling points, however, these effects are large (up to 40% and 20% for the 213 and 193nm lasers, respectively), and variable for the NIST glasses and carbonates. In this paper, a protocol for precise and accurate LA-ICP-MS analysis of calcium carbonates is established. Isotopes for interference-free measurements at low (M/ΔM ~300) and medium (M/ΔM ~4000) mass resolution have been identified. The NIST glasses are suitable for calibration of refractory lithophile element concentrations. However, matrix-matched calibration with carbonate reference materials, such as USGS MACS-1 or MACS-3, is necessary for accurate analysis of chalcophile/siderophile elements with low boiling points. Analytical reproducibility (RSD) is a factor of ~2 better using the 193nm laser than the 213nm laser. As shown by the analysis of MACS-1 and MACS-3, LA-ICP-MS analyses yield results that agree with the reference values within relative uncertainties of ca. 5–10% at the 95% confidence level. We have applied LA-ICP-MS for the determination of trace element concentrations in calcite and aragonite layers of a stalagmite and found large variations for Mg, Zn, Sr, and U. In ostracod shells, the concentrations of some trace elements (e.g., Sr and Ba) vary significantly, indicating the potential for paleoclimate research. [Copyright &y& Elsevier]

Abstract: The deep-sea sponge Monorhaphis chuni forms giant basal spicules, which can reach lengths of 3m; they represent the largest biogenic silica structures on Earth that is formed from an individual metazoan. The spicules offer a unique opportunity to record environmental change of past oceanic and climatic conditions. A giant spicule collected in the East China Sea in a depth of 1110m was investigated. The oxygen isotopic composition and Mg/Ca ratios determined along center-to-surface segments are used as geochemical proxies for the assessment of seawater paleotemperatures. Calculations are based on the assumption that the calculated temperature near the surface of the spicule is identical with the average ambient temperature of 4°C. A seawater temperature of 1.9°C is inferred for the beginning of the lifespan of the Monorhaphis specimen. The temperature increases smoothly to 2.3°C, to be followed by sharply increased and variable temperatures up to 6–10°C. In the outer part of the spicule, the inferred seawater temperature is about 4°C. The lifespan of the spicule can be estimated to 11,000±3000years using the long-term trend of the inferred temperatures fitted to the seawater temperature–age relationships since the Last Glacial Maximum. Specimens of Monorhaphis therefore represents one the oldest living animals on Earth. The remarkable temperature spikes of the ambient seawater occurring 9500–3100yearsB.P. are explained by discharges of hydrothermal fluids in the neighborhood of the spicule. The irregular lamellar organization of the spicule and the elevated Mn concentrations during the high-temperature growth are consistent with a hydrothermal fluid input. [Copyright &y& Elsevier]

We present new reference values for the NIST SRM 610-617 glasses following ISO guidelines and the International Association of Geoanalysts' protocol. Uncertainties at the 95% confidence level (CL) have been determined for bulk- and micro-analytical purposes. In contrast to former compilation procedures, this approach delivers data that consider present-day requirements of data quality. New analytical data and the nearly complete data set of the GeoReM database were used for this study. Data quality was checked by the application of the Horwitz function and by a careful investigation of analytical procedures. We have determined quantitatively possible element inhomogeneities using different test portion masses of 1, 0.1 and 0.02 μg. Although avoiding the rim region of the glass wafers, we found moderate inhomogeneities of several chalcophile/siderophile elements and gross inhomogeneities of Ni, Se, Pd and Pt at small test portion masses. The extent of inhomogeneity was included in the determination of uncertainties. While the new reference values agree with the NIST certified values with the one exception of Mn in SRM 610, they typically differ by as much as 10% from the values in current use. In a few cases (P, S, Cl, Ta, Re) the discrepancies are even higher. [ABSTRACT FROM AUTHOR]

This paper contains the results of an extensive isotopic study of United States Geological Survey GSD-1G and MPI-DING reference glasses. Thirteen different laboratories were involved using high-precision bulk (TIMS, MC-ICP-MS) and microanalytical (LA-MC-ICP-MS, LA-ICP-MS) techniques. Detailed studies were performed to demonstrate the large-scale and small-scale homogeneity of the reference glasses. Together with previously published isotopic data from ten other laboratories, preliminary reference and information values as well as their uncertainties at the 95% confidence level were determined for H, O, Li, B, Si, Ca, Sr, Nd, Hf, Pb, Th and U isotopes using the recommendations of the International Association of Geoanalysts for certification of reference materials. Our results indicate that GSD-1G and the MPI-DING glasses are suitable reference materials for microanalytical and bulk analytical purposes. [ABSTRACT FROM AUTHOR]

This review gives an overview of the literature on reference materials of geochemical and environmental interest for the two-year period 2008-2009. Reference materials play an increasingly important role in all fields of geoanalytical research. This is demonstrated by the large number of publications containing data on reference materials. Although many reference materials exist, there is still a great need for certified samples, so-called delta zero materials for stable isotopic work and homogeneous microanalytical reference materials. This review focuses on six topics: developments of certification processes of reference materials mainly postulated in ISO guidelines and the IAG protocol, new developments of the GeoReM database, investigations of powdered rock reference materials, Chinese reference materials published in Chinese journals, microanalytical reference materials and isotopic reference materials. [ABSTRACT FROM AUTHOR]

The article focuses on the bibliographic review of "Geostandards and Geoanalytical Research."

The article offers information on the 2008 bibliographic review on geology-related topics. The review contains 710 papers from the 2007 issues of different periodicals including "Analytical Sciences," "Geological Magazine" and "Journal of African Earth Sciences." Each paper was evaluated with respect to their application. Results of the review are presented in the GeoReM database.

This review surveys the literature on reference materials for geological and environmental research for the two year period 2006–2007. In this time ca. 1200 publications appeared containing analytical data on reference materials, indicating that their importance for analytical work has been recognised by geochemists and environmental scientists. Although many reference materials exist, there remains a pressing need for further samples, especially for certified rock reference materials, homogeneous reference glasses, mineral reference materials and so-called delta-zero materials for normalisation purposes of stable isotopes. This review focuses on six topics: rock reference materials, reference materials for platinum-group elements, reference glasses, mineral reference materials, environmental reference materials (seawater, soil) and isotopic reference materials (radiogenic, stable isotopes). In addition, a short description is given of the GeoReM database for reference materials of geological and environmental interest, which contains analytical data from the publications discussed in this review. [ABSTRACT FROM AUTHOR]

Abstract: In all fields of geochemical and environmental sample analysis, reference materials play an increasingly important role. Although the provider of an analytical result must document the measurement process used to establish traceability links, most publications do not contain data of reference materials. Therefore, the focus of this paper is to clarify the role and use of reference materials and certified reference materials, to discuss the importance of reference materials for geoanalytical work and to present the GeoReM database for reference materials of geological and environmental interest. The GeoReM database contains published analytical data, compiled data and metadata for about 1800 geochemical and environmental reference materials, provides geoanalysts with details of those samples of particular relevance to applications. Preferred values and their uncertainties are also provided in this database. Although most of the GeoReM preferred values are not ISO compliant, they have a high level of confidence and are therefore useful for calibration purposes and quality control. [Copyright &y& Elsevier]

In this paper we describe a flux-free fusion technique for the highly precise LA-ICP-MS bulk analysis of geological samples. For this purpose we have developed an automated iridium-strip heater with temperature and melt time control. To optimise the homogeneity of the fused glasses and to reduce possible depletion of volatile elements during melting, we undertook experiments with basaltic rock and glass powders using different melting temperatures (1300–1700 °C) and melting times (5-80 s). Major and trace element microanalysis was performed using EPMA and LA-ICP-MS. Homogeneous glasses were obtained for temperatures ≥ 1500 °C and melting times ≥ 10 s. High loss (20-90%) of highly volatile elements (e.g., Cs, Ge, Sn, Pb) was observed for high melting temperatures (≥ 1600 °C) and long melting times (80 s). Standard melting conditions (1600 °C, 10 s) represent a compromise, as the glasses were homogeneous with respect to major and trace elements and, at the same time, were not depleted in elements with condensation temperatures (at a pressure of 10−4 bar) higher than about 900 K (e.g., Zr, Hf, Ba, Sr, REE, U, Mo, Ni, Rb, Ga). Several international geological reference materials with SiO2 ranging between 47% m/m and 59% m/m were prepared using our standard melting conditions (1600 °C, 10 s) and subsequently analysed by LA-ICP-MS. These samples also include the new Brazilian basaltic reference material BRP-1. Matrix-matched calibration of the LA-ICP-MS data was performed using the basaltic reference glasses KL2-G, ML3B-G, BCR-2G and BHVO-2G. Most analytical data agreed within uncertainty at the 95% confidence level with the GeoReM preferred values published in the GeoReM database for reference materials of geological and environmental interest. To demonstrate routine bulk LA-ICP-MS analyses of geochemical and cosmochemical samples using the whole rock fusion technique, we also present trace element data for ocean island basalts from Lanai (Hawaii) and of Martian meteorites. [ABSTRACT FROM AUTHOR]

This sections presents a bibliographic review of several papers focusing on geosciences and other related topics. This review contains two kinds of publications including papers in which analytical data for reference materials of geological and environmental interest have been published in 2006 and papers having data from isotopic standard solutions so-called delta-zero materials and synthetic reference glasses, which are important for calibration and normalisation procedures in geochemical and environmental analysis.

Three natural geological glasses (andesitic glass OJY‐1, and rhyolitic obsidians OH‐1 and OA‐1) of specimen sizes 50–150 g were characterised as reference materials for in situ microanalysis of major and trace elements, and Pb isotope ratios. Utilised techniques include isotope‐dilution analyses by TIMS and MC‐ICP‐MS, bulk analyses by XRF, ICP‐OES, ICP‐MS, and microanalysis (10–120 μm spot size) by electron probe microanalyser, LA‐ICP‐MS and LA‐MC‐ICP‐MS. Microanalyses (10–120 μm) indicate that all three glasses are homogeneous with respect to fifty‐four out of fifty‐eight determined elements and Pb isotope ratios, except for Ni in OJY‐1, and Cu, Zr and Ce in OH‐1. The determination of reference values as well as their uncertainties at the 95% confidence level closely followed International Organization for Standardization (ISO) guidelines and the certification protocol of the International Association of Geoanalysts (IAG). These three glasses are fully natural without any subsequent heat treatment, and they represent useful additions to the widely distributed MPI‐DING, USGS and CGSG reference glasses for microanalytical techniques such as electron probe microanalysis, μ‐XRF, LA‐ICP‐MS and SIMS. [ABSTRACT FROM AUTHOR]

• Ultramafic and mafic igneous rocks from a 570 Ma Paleo-island arc. • Petrogenetic processes during lower and middle arc crust formation. • Origin of wehrlites and pyroxenites from individual picritic to boninitic melt batches. • Gabbroic rocks from differentiated magmas crystallized in a single intrusive body. The Agardagh Tes-Chem complex (ATCC) in Tuva, Central Asia (50.5°N, 95°E) exposes a rare mafic to ultramafic crust-mantle fragment that developed within a late Neoproterozoic (~570 Ma) intra-oceanic island arc system that was accreted to the Tuva-Mongolian microcontinent during the formation of the Central Asian Orogenic Belt. Residual mantle rocks (harzburgites and dunites) are highly refractory with high Cr# (0.59–0.83) and intermediate Mg# (0.46–0.52) in spinel and experienced high degrees of total melt extraction (up to 25%). In ultramafic cumulate rocks (wehrlites and pyroxenites), Cr# and Mg# in spinel are distinctly lower (0.22–0.45 and 0.34–0.37), and rare earth element (REE) abundances of clinopyroxenes range between 0.1 and 1-times chondritic with chondrite normalized La/Yb of ~0.04. Trace element abundances in wehrlite clinopyroxene are lower than in pyroxenite clinopyroxene, whereas all have positive Sr but pronounced negative Zr anomalies. Calculated equilibrium melts of wehrlites and clinopyroxenites suggest strongly depleted hydrous high-MgO high-SiO 2 primary magmas (picrites to boninites) from which these rocks have evolved. Incompatible trace element concentrations in mafic (i.e. gabbroic to dioritic) rocks vary strongly with REE contents between ~0.7 and 20-times chondritic, and chondrite normalized La/Yb between 0.25 and 0.98. Initial ε Nd varies between +4.8 and +7.1. These features, along with the broad textural and modal variations indicate that the mafic rocks developed from a single intrusive body that underwent substantial crustal assimilation. Cr and Ni contents in the mafic rocks are low and indicate their formation from already differentiated magmas. The evolution of the ATCC prior to amalgamation is explained by a two stage magmatic process. During the initial stages of melting low degree magmas evolved from a refractory mantle wedge fluxed by hydrous fluids and sediments or sediment derived melts to form enriched upper crustal shallow level intrusive and extrusive rocks. Later stage melting from a less hydrous and more depleted but SiO 2 -enriched source produced the parental picrites/boninites from which the lower and middle arc crustal rocks formed. These magmas differentiated within at least two distinct magma reservoirs at lowermost crustal levels, where cumulate wehrlites formed mostly independently from cumulate pyroxenites. This is evident from distinctly different trace-element compositions of these two rock types. The wehrlite derivative magmas subsequently intruded to mid-crustal levels where they crystallized the mafic rocks within a single intrusion, but accompanied by assimilation of preexisting enriched arc crust. [ABSTRACT FROM AUTHOR]

To expand the newly developed ARM glasses as reference materials for in situ microanalysis of isotope ratios and iron oxidation state by a variety of techniques such as SIMS, LA‐MC‐ICP‐MS and EPMA, we report Li‐B‐Si‐O‐Mg‐Sr‐Nd‐Hf‐Pb isotope data and Fe2+/ΣFe ratios for these glasses. The data were mainly obtained by TIMS, MC‐ICP‐MS, IR‐MS and wet‐chemistry colorimetric techniques. The quality of these data was cross‐checked by comparing different techniques or by comparing the results from different laboratories using the same technique. All three glasses appear to be homogeneous with respect to the investigated isotope ratios (except for B in ARM‐3) and Fe2+/ΣFe ratios at the scale of sampling volume and level of the analytical precision of each technique. The homogeneity of Li‐B‐O‐Nd‐Pb isotope ratios at the microscale (30–120 μm) was estimated using LA‐MC‐ICP‐MS and SIMS techniques. We also present new EPMA major element data obtained using three different instruments for the glasses. The determination of reference values for the major elements and their uncertainties at the 95% confidence level closely followed ISO guidelines and the Certification Protocol of the International Association of Geoanalysts. The ARM glasses may be particularly useful as reference materials for in situ isotope ratio analysis. [ABSTRACT FROM AUTHOR]

Two small stalagmites from Zoolithencave (southern Germany) show annual lamination and are dated to AD 1821 to 1970 (Zoo-rez-1) and AD 1835 to 1970 (Zoo-rez-2). Chronologies of the two stalagmites were conducted by 14C bomb peak detection at the top of both stalagmites, 14C-dating of a piece of charcoal from the consolidated base part of Zoo-rez-2, lamina counting, and cross-dating of the laminae (Riechelmann et al., in review). The concentration of Mg, Ba, Sr, Al, P, and Y of both stalagmites was measured by LA-ICP-MS. Samples for d18O and d13C analyses were micro milled with a resolution of 50 µm in Zoo-rez-1 and 130 µm in Zoo-rez-2, which corresponds to a resolution of three samples per year for Zoo-rez-1 and an annual resolution for Zoo-rez-2. Soil and host rock samples were analysed by XRD and their Ca, Mg, Sr, and Ba concentrations determined via ICP-OES. Meteorological and GNIP station data were used for comparison with the proxy data, calculating the infiltration, and modelling the d18O values of the calcite precipitating in the cave using the model of Wackerbarth et al. (2010). Modelled and the measured d18O values of the two stalagmites show similar patterns. This can be explained by the transfer of the rainwater d18O signal into speleothem calcite. The d18O values of the rainwater reflect local temperatures. Therefore, the d18O of the stalagmites can be used as a temperature proxy and provide the opportunity to calibrate the proxy in the time interval overlapping with meteorological data. The studied element concentrations show two groups in the principal component analysis, one with Mg, Ba, and Sr and the other with Y, P, and Al, respectively. The second group is influenced by detrital material in the stalagmites. Prior calcite precipitation does not have an influence on the Mg, Ba, and Sr concentrations. Mg shows a correlation with d18O which suggests an influence of temperature on the leaching of Mg from the soil and the dolomitic host rock. Especially, Ba shows a strong leaching from the soil because the Ba concentration in the stalagmites is higher than in the host rock.Riechelmann, D.F.C., Fohlmeister, J., Kluge, T., Jochum, K.P., Richter, D.K., Deininger, M., Friedrich, R., Frank, N., Scholz, D., in review. Evaluating the potential of tree-ring methodology for cross-dating of annually laminated stalagmites. Quaternary Geochronology.Wackerbarth, A., Scholz, D., Fohlmeister, J., Mangini, A., 2010. Modelling the d18O value of cave drip water and speleothem calcite. Earth and Planetary Science Letters 299, 387-397. [ABSTRACT FROM AUTHOR]

To assess the homogeneity of and provide the first Sr‐Nd‐Hf‐Pb isotopic reference values for the Chinese Geological Standard Glasses CGSG‐1, CGSG‐2, CGSG‐4 and CGSG‐5, we measured these isotopes in several measurement sessions over the course of nearly 3 years. The results were obtained by high‐precision MC‐ICP‐MS and TIMS. Our investigation indicates that these CGSG glass reference materials are homogenous with regard to Sr‐Nd‐Hf‐Pb isotopic distribution and are therefore suitable geochemical materials for Sr‐Nd‐Hf‐Pb isotope measurements. Clear differences in Sr‐Nd‐Hf‐Pb isotopic composition were observed between the glasses and the original powdered rock reference materials (CGSG‐2 and GSR‐7, and especially CGSG‐5 and GSR‐2) because of flux addition during preparation of the glasses. The new Sr‐Nd‐Hf‐Pb isotope data provided here might be useful to the geochemical community for in situ and bulk analysis. [ABSTRACT FROM AUTHOR]

Three synthetic reference glasses were prepared by directly fusing and stirring 3.8 kg of high‐purity oxide powders to provide reference materials for microanalytical work. These glasses have andesitic major compositions and are doped with fifty‐four trace elements in nearly identical abundance (500, 50, 5 µg g−1) using oxide powders or element solutions, and are named ARM‐1, 2 and 3, respectively. We further document that sector‐field (SF) ICP‐MS (Element 2 or Element XR) is capable of sweeping seventy‐seven isotopes (from 7Li to 238U, a total of sixty‐eight elements) in 1 s and, thus, is able to quantify up to sixty‐eight elements by laser sampling. Micro‐ and bulk analyses indicate that the glasses are homogeneous with respect to major and trace elements. This paper provides preliminary data for the ARM glasses using a variety of analytical techniques (EPMA, XRF, ICP‐OES, ICP‐MS, LA‐Q‐ICP‐MS and LA‐SF‐ICP‐MS) performed in ten laboratories. Discrepancies in the data of V, Cr, Ni and Tl exist, mainly caused by analytical limitations. Preliminary reference and information values for fifty‐six elements were calculated with uncertainties [2 relative standard error (RSE)] estimated in the range of 1–20%. [ABSTRACT FROM AUTHOR]

This Geostandards and Geoanalytical Research Bibliographic Review 2022 presents an overview of a wide range of publications in 2022 focusing on the characterisation of new geoanalytical reference materials (RMs) as well as studies which published measurement results for established RMs. The development of highly accurate new methods and techniques leads to large new analytical data sets for RMs with improved accuracy and precision, which we present in this review. [ABSTRACT FROM AUTHOR]

Understanding supra-regional climate variability such as the changes in the North Atlantic realm is important to identify the drivers of the climate system. In this study maar lake sediments from the Eifel (western Germany) were analysed with a multi-proxy approach and compared to central and western European speleothem growth phases. C org (chlorins) and the pollen assemblage were analysed from two sediment cores of the Hoher List infilled maar lake. To generate C org (chlorins) and pollen records covering the entire last 130,000 yr b2k (years before year 2000 CE), the data from this study were stacked with published data from other Eifel maar lake sediment cores (Sirocko et al., 2013, 2021, 2022). The sediment cores from Hoher List infilled maar lake were dated by marker tephra layers giving chronological anchor points and the precise dating of the sediment cores was performed by the tuning of the C org (chlorins) records to the NGRIP δ18O record (Rasmussen et al., 2014). The speleothems, whose growth phases are compared to the lake sediment proxy records, were compiled from the literature as well as speleothems from Dechencave (western Germany) dated by the 230Th/U-method in this study. The C org (chlorins) variability shows the bioproductivity in the maar lake, which is related to water temperature and corresponds to the Greenland Interstadials (GIs) in the NGRIP δ18O record indicates its dependence on supra-regional climate variations in the North Atlantic. The pollen record shows three periods of forest with temperate forest species, during the Eemian, early Marine Isotope Stage (MIS) 3, and the Holocene. Speleothem growth in four caves in central and western Europe (Dechencave, Spannagel Cave, Hölloch Cave, Villars Cave) is predominantly sensitive to cold periods with glaciers and/or permafrost conditions above the caves inhibiting speleothem growth. The forested phases and phases of high bioproductivity in the Eifel correspond well with phases of speleothem growth indicating three warm phases in central Europe during the last glacial cycle. [ABSTRACT FROM AUTHOR]

Ba/Cashell, Mo/Cashell, and Li/Cashell chronologies of Pecten maximus can provide information on past phytoplankton dynamics. Distinct Ba, Mo, and Li peaks in the shells are associated with algal blooms. This study evaluated the underlying hypothesis that respective element profiles reliably record variations in phytoplankton dynamics occurring within the water column. Therefore, the chemical content of scallops from the Bay of Brest, France, that lived on the sediment surface was compared to conspecific specimens living in a cage above the seafloor and compared with the phytoplankton abundance and the physicochemical properties of the water column. As demonstrated, Ba/Cashell and Mo/Cashell peaks occurred contemporaneously in specimens within the cage and on the sediment, but were higher in the latter. Furthermore, element/Ca peaks agreed with the timing of particulate Ba and Mo enrichments in the seawater. These data support the assumption of a dietary uptake of both elements. Differences in peak heights between shells living in a cage and on the seafloor were controlled by rates of filtration and biomineralization. While the timing and magnitude of Ba/Cashell peaks were linked to Ba‐containing diatoms, Mo/Cashell peaks were related to blooms of Mo‐enriched dinoflagellate and diatom aggregation events. Two episodes of slight Li enrichment occurred synchronously in cage and sediment shells. Although the exact mechanism causing such Li increases remains unresolved, the findings suggest a link to large diatom blooms or the presence of a specific diatom taxon. This study refines previously hypothesized relationships between trace element enrichments in scallop shells and phytoplankton dynamics. [ABSTRACT FROM AUTHOR]

As part of the HIPPO (HIgh-resolution Primary Production multi-prOxy archives) project, environmental monitoring was carried out between March and October 2021 in the Bay of Brest. The aim of this survey was to better understand the processes which drive the incorporation of chemical elements into scallop shells and their links with phytoplankton dynamics. For this purpose, biological samples (scallops and phytoplankton) as well as water samples were collected in order to analyze various environmental parameters (element chemical properties, nutrients, chlorophyll a , etc.). Given the large number of parameters that were measured, only the major results are presented and discussed here. However, the whole dataset, which has been made available, is much larger and can potentially be very useful for other scientists performing sclerochronological investigations, studying biogeochemical cycles or conducting various ecological research projects. The dataset is available at 10.17882/92043 (Siebert et al., 2023). [ABSTRACT FROM AUTHOR]

In situ laser ablation analyses rely on the microanalytical homogeneity of reference materials (RMs) and a similar matrix and mass fraction between unknown samples and RMs to obtain reliable results. Suitable carbonate and phosphate RMs for determination of Sr isotope ratios in such materials are limited. Thus, we determined 87Sr/86Sr ratios of several carbonate (JCt‐1, JCp‐1, MACS‐1, MACS‐3) and phosphate (MAPS‐4, MAPS‐5, NIST SRM 1400, NIST SRM 1486) international RMs using dissolved samples and two different multi‐collector inductively coupled plasma‐mass spectrometers (MC‐ICP‐MS). Our Sr isotope data are in agreement with published data and have an improved measurement precision for some RMs. For MACS‐1, we present the first 87Sr/86Sr value. We tested the suitability of these materials for microanalytical analyses by LA‐MC‐ICP‐MS, with two different laser ablation systems: a conventional nanosecond laser and a state‐of‐the‐art femtosecond laser. We investigated the RMs micro‐homogeneity and compared the data with our solution data. Both laser ablation systems yielded identical 87Sr/86Sr ratios within uncertainty to the solution data for RMs with low interferences of REEs. Therefore, these carbonate and phosphate RMs can be used to achieve accurate and precise results for in situ Sr isotope investigations by LA‐MC‐ICP‐MS of similar materials. [ABSTRACT FROM AUTHOR]

Black manganese-rich crusts are found worldwide on the façades of historical buildings. In this study, they were studied exemplarily on the façade of the Freiburger Münster (Freiburg Minster), Germany, and measured in-situ by portable X-ray fluorescence (XRF). The XRF was calibrated to allow the conversion from apparent mass fractions to Mn surface density (Mn mass per area), to compensate for the fact that portable XRF mass fraction measurements from thin layers violate the assumption of a homogeneous measurement volume. Additionally, 200-nm femtosecond laser ablation-inductively coupled plasma-mass spectrometry (fs LA-ICP-MS) measurements, scanning transmission X-ray microscopy-near edge X-ray absorption fine structure spectroscopy (STXM-NEXAFS), Raman spectroscopy, and imaging by light microscopy were conducted to obtain further insight into the crust material, such as potential biogenic contributions, element distributions, trace element compositions, and organic functional groups. While black crusts of various types are present at many places on the minster's facade, crusts rich in Mn (with a Mn surface density >150 μg cm −2 ) are restricted to a maximum height of about 7 m. The only exceptions are those developed on the Renaissance-Vorhalle (Renaissance Portico) at a height of about 8 m. This part of the façade had been cleaned and treated with a silicon resin as recently as 2003. These crusts thus accumulated over a period of only 12 years. Yet, they are exceptionally Mn-rich with a surface density of 1200 μg cm −2 , and therefore require an accumulation rate of about 100 μg cm −2 Mn per year. Trace element analyses support the theory that vehicle emissions are responsible for most of the Mn supply. Lead, barium, and zinc correlate with manganese, indicating that tire material, brake pads, and resuspended road dust are likely to be the element sources. Microscopic investigations show no organisms on or in the Mn-rich crusts. In contrast, Mn-free black crusts sampled at greater heights (>8 m) exhibited fungal and cyanobacterial encrustation. Carbon-rich spots were found by STXM-NEXAFS underneath one of the Mn-rich crusts. However, these carbon occurrences originate from soot and polycyclic aromatic hydrocarbons (PAHs) deposited on top of the crust, rather than from organisms responsible for the crust's formation, as shown by STXM-NEXAFS and Raman spectroscopic measurements. Our results suggest that the crusts develop abiogenically, with vehicle emissions as dominant element sources. [ABSTRACT FROM AUTHOR]

Speleothems are well established climate archives. A wide array of geochemical proxies, including stable isotopes and trace elements are present within speleothems to reconstruct past climate variability. However, each proxy is influenced by multiple factors, often hampering robust interpretation. Sr isotope ratios ( 87 Sr/ 86 Sr) can provide useful information about water residence time and water mixing in the host rock, as they are not fractionated during calcite precipitation. Laser ablation multi-collector-inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) has rarely been used for determination of Sr isotope signatures in speleothems, as speleothems often do not possess appropriately high concentrations of Sr to facilitate this analysis. Yet the advantages of this approach include rapid data acquisition, higher spatial resolution, larger sample throughput and the absence of chemical treatment prior to analysis. We present LA-MC-ICP-MS Sr isotope data from two speleothems from Morocco (Grotte de Piste) and India (Mawmluh Cave), and we compare linescan and spot analysis ablation techniques along speleothem growth axes. The analytical uncertainty of our LA-MC-ICP-MS Sr data is comparable to studies conducted on other carbonate materials. The results of both ablation techniques are reproducible within analytical error, implying that this technique yields robust results when applied to speleothems. In addition, several comparative measurements of different carbonate reference materials (i.e. MACS-3, JCt-1, JCp-1), including tests with standard bracketing and comparison of the 87 Sr/ 86 Sr ratios with a nanosecond laser ablation system and a state-of-the-art femtosecond laser ablation system, highlight the robustness of the method. [ABSTRACT FROM AUTHOR]

RATIONALE: High spatial resolution Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS) determination of trace element concentrations is of great interest for geological and environmental studies. Data reduction is a very important aspect of LA-ICP-MS, and several commercial programs for handling LA-ICPMS trace element data are available. Each of these software packages has its specific advantages and disadvantages. METHODS: Here we present TERMITE, an R script for the reduction of LA-ICPMS data, which can reduce both spot and line scan measurements. Several parameters can be adjusted by the user, who does not necessarily need prior knowledge in R. Currently, ten reference materials with different matrices for calibration of LA-ICPMS data are implemented, and additional reference materials can be added by the user. TERMITE also provides an optional outlier test, and the results are provided graphically (as a pdf file) as well as numerically (as a csv file). RESULTS: As an example, we apply TERMITE to a speleothem sample and compare the results with those obtained using the commercial software GLITTER. The two programs give similar results. TERMITE is particularly useful for samples that are homogeneous with respect to their major element composition (in particular for the element used as an internal standard) and when many measurements are performed using the same analytical parameters. In this case, data evaluation using TERMITE is much faster than with all other available software, and the concentrations of more than 100 single spot measurements can be calculated in less than a minute. CONCLUSIONS: TERMITE is an open-source software for the reduction of LA-ICPMS data, which is particularly useful for the fast, reproducible evaluation of large datasets of samples that are homogeneous with respect to their major element composition. [ABSTRACT FROM AUTHOR]

As part of the HIPPO (HIgh-resolution Primary Production multi-prOxy archives) project, an environmental monitoring was carried out between March and October 2021 in the Bay of Brest. The aim of this survey was to better understand the processes which drive the incorporation of chemical elements into scallop shells and their links with phytoplankton dynamics. For this purpose, biological samples (scallops and phytoplankton) as well as water samples were collected in order to analyse various environmental parameters (element chemical properties, nutrients, chlorophyll, etc.). Here, some of the monitoring data 5 are presented and discussed. The whole dataset is much larger and can potentially be very useful for other scientists performing sclerochronological investigations, studying biogeochemical cycles or conducting various ecological research projects. [ABSTRACT FROM AUTHOR]

This GGR Bibliographic Review is a survey of approximately 5200 geoanalytical publications for the year 2021. Selected articles, numbering over 340, containing measurement results for relevant geological and environmental reference materials are listed with individual summaries of target analytes, relevant reference materials and producers. A brief summary of a selection of these publications is included that highlights notable developments in geoanalytical studies, newly developed or characterised RMs, and new datasets of established reference materials that have been re‐analysed using improved or state‐of‐the‐art measurement techniques. [ABSTRACT FROM AUTHOR]

We studied an aragonitic section of ca. 6 cm length of stalagmite HBSH-1 from the Hüttenbläserschachthöhle, western Germany. 230 Th/U-dating revealed that this section grew between ~ 210 and ~ 190 ka, with a relatively uniform growth rate of 3.1 μm a − 1 . For the first time, we determined Pb isotope ratios ( 207 Pb/ 206 Pb and 208 Pb/ 206 Pb) in a stalagmite by laser ablation (LA)-ICP-MS. In addition, we analyzed various trace element (Mg, Al, Si, P, Mn, Sr, Pb and Th) concentrations. The results indicate that Pb in HBSH-1 originated from two external sources: (i) the regional galena (PbS) mineralization with high Pb content as well as isotope ratios, and (ii) the carbonate fraction in the host rock with low Pb content as well as isotope ratios. Except for Sr, all trace elements show similar variations, probably driven by the amount of infiltration into the cave system. This is probably the result of the similar transport and incorporation mechanisms of these elements as colloids and/or particles. The Pb isotope ratios also show a strong correlation with trace element variability strongly suggesting that the Pb isotope variability in HBSH-1 has the potential to be used as a promising new proxy for hydrological change. Based on the observed variability, we identify two phases (from ~ 204.9 to ~ 201.5 and from ~ 198.4 to ~ 195.9 ka) with enhanced water infiltration in the cave region. Between ~ 210.0 and ~ 204.9, ~ 201.5 and ~ 198.4 as well as ~ 195.9 and ~ 190.0 ka less infiltration occurred. [ABSTRACT FROM AUTHOR]

Hadean zircons, from the Jack Hills (Western Australia) and other localities, are currently the only window into the earliest terrestrial felsic crust, the formation of which remains enigmatic. Based upon new experimental results, generation of such early crust has been hypothesized to involve the partial melting of hydrated peridotite interacting with basaltic melt at low pressure (<10 km), but it has yet to be demonstrated that such liquids can indeed crystallize zircons comparable to Jack Hills zircon. We used thermodynamic and geochemical modeling to test this hypothesis. The predicted zircon saturation temperatures of <750 °C, together with the model zircon Th, U, Nb, Hf, Y, and rare earth element (REE) contents at 700 °C, δ18OVSMOW (Vienna standard mean ocean water) signatures, and co-crystallizing mineral assemblage were compared to those of the Jack Hills zircon. This comparison was favorable with respect to crystallization temperature, most trace-element contents, and mineral inclusions in zircon. The discrepancy in δ18OVSMOW signatures may be explained by hotter conditions of Hadean protocrust hydration. Our work supports the idea that felsic magma generation at shallow depths involving a primordial weathered ultramafic protocrust and local basaltic intrusions is indeed a viable mechanism for the formation of felsic crust on early Earth. [ABSTRACT FROM AUTHOR]

Phytoplankton dynamics in coastal ecosystems is increasingly altered by land‐based human activities. Yet, this global vision conceals major disparities, among sites and through time. As conventional monitoring time series are quite sparse and relatively short, biological records of environmental variability appear as relevant tools to gain insights into phytoplankton dynamics over larger temporal and spatial scales. Here, we present results of an interdisciplinary project dealing with chemical information archived in shells of Pecten maximus (Bivalvia; Pectinidae), known to form daily growth striae on its shell surface. Several individuals were collected in the Bay of Brest (France) in 2011 and 2012, and analyzed for the molybdenum and lithium concentrations in their soft tissues and the element‐to‐calcium ratios (Mo : Ca and Li : Ca) in their calcitic striae. All shells revealed high synchrony and reproducibility in their Mo : Ca and Li : Ca profiles, characterized with a major peak at the end of May and in mid‐June 2011, respectively. Detailed analysis of physical, chemical, and biological variables measured in seawater during an extensive 9‐month environmental survey enabled a meticulous description of phytoplankton dynamics in 2011 and its impact on shell geochemistry. Main findings strongly suggest that (1) the timing of Mo : Ca peaks reflects the occurrence of silicon limitation and diatom aggregation periods, (2) the height of these peaks relates to the amplitude of the first spring diatom bloom, and (3) Li : Ca serves as a proxy for the temporal dynamics of diatom biovolume and of biogenic silica recycling at the sediment–water interface. [ABSTRACT FROM AUTHOR]