Provenance Identification Research Articles

Sulfur K-edge XANES of lazurite: Toward determining the provenance of lapis lazuli

Lazurite, the blue mineral found in lapis lazuli, may be a marker for the identification of provenance. Sulfur K-edge X-ray absorption near edge structure spectroscopy (XANES) of lazurite from lapis lazuli of various locations, such as Afghanistan, Russia, Chile, the USA, Iran, Tajikistan, and Myanmar, is described. The XANES spectra reveal that several different sulfur chemistries exist within lazurite, attributed to contributions from multiple sulfur species. A peak at 2482.5eV is attributed to sulfate; an envelope of peaks between 2470 and 2475eV is attributed to polysulfide radicals, polysulfide dianions, neutral sulfur, and/or thiosulfate; and a peak at 2469.1eV is attributed to the trisulfur and/or disulfur radical(s). Also, a peak of unknown origin arises at 2466.3eV in several spectra. The spectral profile for the envelope of peaks (2470 to 2475eV) varies between samples and in some instances, within a sample. Most notably, the studied samples from Chile display two distinct peaks near 2471.7 and 2473.5eV with a local minimum at 2472.5eV, unlike the most commonly observed pattern—that typically observed for samples from Afghanistan—with a single maximum intensity near 2472.5eV. Other more subtle variations in this energy range also correlate with provenance at varying degrees.

First Investigations of In Situ Electrical Properties of Limestone Blocks of Ancient Monuments

In situ rapid electrostatic investigations on calcareous stones of monuments provide information that strongly correlates with the geological characteristics of the stone and proves to be efficient for provenance identification and successive restoration. With a portable device, it is now possible to scan several thousand blocks on a face of a monument in a few hours. The evolution of the religious building construction practices between the 13th and the 17th centuries is studied. From the petrophysics point of view, the results clearly indicate a marked linear correlation between electrical conductivity and dielectric permittivity. This fact, which agrees with Maxwell–Wagner polarization modelling, confirms the part played by the clay content in the electric properties of the dry carbonate rocks constituting the monument stones. A first test using X‐ray scattering analysis shows the part played by the relative content of illite, which is correlated with a decrease of the resistivity.

Evidence for stable Sr isotope fractionation by silicate weathering in a small sedimentary watershed in southwestern Taiwan

Radiogenic Sr isotopes (87Sr/86Sr) are robust for provenance identification in hydrology, affected mainly by the age of background lithologies and the degree of chemical weathering. However, there is limited knowledge concerning the fractionation mechanism of stable Sr isotopes (88Sr/86Sr) in rivers. In this study, river water was collected on a weekly to monthly basis throughout dry and wet seasons. Furthermore, to study the variations of radiogenic and stable Sr isotopes during intense weathering, a major flooding event (2000mm precipitation in three days, Typhoon Morakot), water was captured within a small drainage catchment system (161km2) along the Hou-ku River in southwestern Taiwan. For a better constraint on the end member compositions, bedload sediments, suspended particles, and several host rocks were sampled for a systematic investigation. The carbonate and silicate phases of these solids were chemically separated. Dissolved major elements indicate that the watersheds were predominated by silicate weathering. Stable Sr isotopes show no significant variation (δ88Sr=0.24–0.31‰) temporally and spatially with an average of 0.28‰. Additionally, all solids showed lower δ88Sr values than the river water while the host rocks had higher δ88Sr values (δ88Sr=0.20–0.26‰) than the residual weathering products (δ88Sr=0.08–0.22‰), indicating preferential leaching of heavy Sr into the hydrosphere and leaving light Sr in the residual solids. Results of laboratory acid leaching experiments reveal that dissolution of high δ88Sr value minerals occurred at an early stage of weathering. The variation of weathering intensity does not alter stable Sr isotopes in silicate weathering dominated river water, which contains higher stable Sr isotopes than the associated sediments. The silicatic sedimentary rocks preferentially released higher stable Sr isotopes into the hydrosphere during chemical weathering, thus leaving lower stable Sr isotopes in the residual solids.

Archaeological and archaeometric study of the glass finds from the ancient harbour of Classe (Ravenna- Italy): new evidence

The present study focuses on Late-Roman/Early Medieval glass found in the productive area within the ancient harbour of Classe near Ravenna, one of the most important trade centres between the 5th and 8th centuries AD of the Northern Adriatic area. Aims of the study were the identification of the main glass compositions and their contextualisation in Late-Antique groups; the identification of provenance of raw glass, and, consequently, of commercial routes; the extent, if any, of recycling glass cullet, as an alternative to the import of fresh raw glass; the identification of possible connections between archaeological typology and glass chemical composition. 32 glassworking wastes and 25 drinking vessel fragments for a total amount of 57 fragments were devoted to chemical analysis in XRF and EPMA. All the analysed fragments are silica-soda lime glasses, produced with natron as a flux, and are compositionally similar to Late-Antique groups HIMT, Serie 3.2 and Levantine1. Raw glass chunks, glassworking wastes and objects of comparable compositions are identified into HIMT and Serie 3.2 groups, while the Levantine 1 group includes only objects and glassworking wastes. Systematic comparisons between Classe and Aquileia, the two most important Late-Antique archaeological sites of North-Eastern Italy, were also carried out, and the same compositional groups were identified, although Serie 3.2 in the Classe assemblage is more represented. Sr and Nd isotopic analysis confirmed that the composition of the three glasses derive from coastal sands of the Syro-Palestinian and Egyptian shore, with a slight shift in comparison to the published data. Little evidence of recycling was identified in the assemblage. In the 5th century, a secondary glass workshop devoted to the shaping of glass vessels starting from raw glass chunks and, possibly, glass cullet, was active in the area of the harbour. Raw glass of HIMT and Serie 3.2 was imported from the Levant and Egypt. Comparisons between Classe and Aquileia show that during the Late Antiquity these sites seem to be supplied of raw glass by the same trade routes. In addition, some connections between types and chemical compositions were highlighted.

The role of U-Pb ages of detrital zircons in sedimentology—An alarming case study for the impact of sampling for provenance interpretation

U-Pb ages on detrital zircons are often utilised for stratigraphic and paleogeographic interpretations and correlation. Sampling is carried out in such a way that the samples are representative for a formation, and then used for provenance identification and/or defining a maximum time limit for deposition. Is it possible that sedimentological factors and sampling would influence the results? This is perhaps an obvious consideration for sedimentologists, but is in many studies treated as asecondary concern or even not mentioned.U-Pb LA-ICP-MS analysis on detrital zircons from two samples of Cambrian age (Herrería Formation, Cantabrian Mountains, Spain) revealed very different provenance signatures at the base and top of the formation. Both successions have been deposited in a shallow marine environment, are lithologically comparable (arenites, feldspathic arenites, siltstone, shales intercalated with marls and dolomite) and differ only slightly in age. Nearly 80% of all detrital zircons (n=152; discordance≤10) at the base of the formation are younger than 650Ma. Detrital zircons older than 1.0Ga amount to only 10% (n=16) of the entire population. In contrast, only around 32% of all detrital zircons from the top of the formation (n=123; discordance ≤10) are younger than 650Ma while more than 16% are Archean and nearly 50% Paleoproterozoic. This implies a fundamental change in provenance, with a shift from Neoproterozoic to Paleoproterozoic (1.9–2.2Ga) aged sediment sources. Consequently, changes of sediment transport systems have had an extremely profound impact on the provenance of the formation. Therefore, when correlating sedimentary rocks, interpreting source rocks and modelling paleogeography from U-Pb ages of detrital zircons, sedimentological parameters are possibly paramount and these need to be at least discussed before any interpretation is made.

CFD simulation on the generation of turbidites in deepwater areas: a case study of turbidity current processes in Qiongdongnan Basin, northern South China Sea

Turbidity currents represent a major agent for sediment transport in lakes, seas and oceans. In particular, they formulate the most significant clastic accumulations in the deep sea, which become many of the world’s most important hydrocarbon reservoirs. Several boreholes in the Qiongdongnan Basin, the northwestern South China Sea, have recently revealed turbidity current deposits as significant hydrocarbon reservoirs. However, there are some arguments for the potential provenances. To solve this problem, it is essential to delineate their sedimentary processes as well as to evaluate their qualities as reservoir. Numerical simulations have been developed rapidly over the last several years, offering insights into turbidity current behaviors, as geologically significant turbidity currents are difficult to directly investigate due to their large scale and often destructive nature. Combined with the interpretation of the turbidity system based on high-resolution 3D seismic data, the paleotophography is acquired via a back-stripping seismic profile integrated with a borehole, i.e., Well A, in the western Qiongdongnan Basin; then a numerical model is built on the basis of this back-stripped profile. After defining the various turbidity current initial boundary conditions, including grain size, velocity and sediment concentration, the structures and behaviors of turbidity currents are investigated via numerical simulation software ANSYS FLUENT. Finally, the simulated turbidity deposits are compared with the interpreted sedimentary bodies based on 3D seismic data and the potential provenances of the revealed turbidites by Well A are discussed in details. The simulation results indicate that a sedimentary body develops far away from its source with an average grain size of 0.1 mm, i.e., sand-size sediment. Taking into account the location and orientation of the simulated seismic line, the consistence between normal forward simulation results and the revealed cores in Well A indicates that the turbidites should have been transported from Vietnam instead of Hainan Island. This interpretation has also been verified by the planar maps of sedimentary systems based on integration of boreholes and seismic data. The identification of the turbidity provenance will benefit the evaluation of extensively distributed submarine fans for hydrocarbon exploration in the deepwater areas.

Analysis of the elemental composition of Tang Sancai from the four major kilns in China using EDXRF

Tang Sancai was widely used in the Tang Dynasty, and the study of this pottery provides information about the sociocultural aspects of the Tang people. To understand the characteristics of the different kilns for the production of Tang Sancai, Energy Dispersive X-ray Fluorescence (EDXRF) was used to analyze 174 Tang Sancai shards. These specimens were selected from four production centers in the Tang Dynasty, namely, the Huangye Kiln, the Huangbu Kiln, the Xing Kiln and the Liquanfang Kiln. The results demonstrate that the clay bodies from different kilns have varying compositions, and each kiln has a unique elemental fingerprint. Of the 17 elements analyzed, TiO2 and Fe2O3 had distinctly different contents in the samples from the Huangye Kiln and the Huangbu Kiln. For the Xing Kiln and the Huangye Kiln, the characteristic elements are Fe2O3 and MnO. For the Xing Kiln and the Huangbu Kiln, the most dissimilar elements are TiO2, MnO and ZnO. When the Principal Component Analysis (PCA) was employed, the data points for the Huangye Kiln, the Huangbu Kiln and the Xing Kiln fell into distinct areas. For the Liquanfang Kiln, the contents of Al2O3 and Fe2O3 in white-bodied samples are different from those of other colors, which indicates that at least two types of raw materials were used. When compared with the white-bodied samples from the other three kilns, the white-bodied samples from the Liquanfang Kiln were found to have compositions similar to those of the samples from the Huangye Kiln, rather than the Huangbu Kiln, although the latter is much closer geographically than the former. All the obtained data provide valuable scientific criteria for provenance identification for Tang Sancai of unknown origin.

Grape brandy production, composition and sensory evaluation

Grape brandy is a spirit drink produced by wine distillation and is matured in wooden casks. According to legislation, it can be characterised by the geographical area where the grapes were produced, the grape variety used and the selected distillation and ageing techniques. Distillation increases ethanol concentration and aromatic constituents which are already present in grapes or are developed during fermentation and distillation. During maturation in wooden casks, compounds that contribute to the aroma and taste are extracted from the wood. Hence the spirit acquires the desired softer mouth feel, aromatic complexity and overall quality. Different methods of analysis are used in order to pursuit this process by analysing volatile and non-volatile substances and correlate composition with quality. Analysis can also be useful in identification of brandy safety, potential adulterations, provenance and differentiation from other spirits drinks.

Petrographic characterization and provenance determination of the white marbles used in the Roman sculptures of Forum Sempronii (Fossombrone, Marche, Italy)

The Roman municipium of Forum Sempronii (Fossombrone, Marche) was located along the 'Via Con- solare Flaminia', in the stretch of road where it ran along the final sector of the valley of the River Metauro (Matau- rus). The ancient colony of Forum Sempronii, which is cited by Strabo, Pliny, and Ptolemy, was found in the second cen- tury BC, probably on the site of an earlier community and its activity continued until the end of the fifth century AD. During ancient and more recent archaeological excavations, many fragments of coloured stones and marbles, and some white marble sculptures have been unearthed. In this paper, we report the results of the provenance identification of the white marbles used for the sculptures found in the archaeological site of Forum Sempronii and now displayed at the local archaeological museum. The de- termination of the source origin of the white marbles used for the sculptures has been established by mineralogical-

Identification of wine provenance by ICP-AES multielement analysis

We have estimated the possibility of identifying the provenance of some natural wines produced in the Krasnodar region. The macro- and microelement composition of wines and soils from the place of grape origin has been used as the classification criterion. The main elements indicating the wine provenance, Al, Co, Cu, Mn, Ti, Zn, Ba, and Rb have been determined by inductively coupled plasma atomic emission spectroscopy. We have revealed the possibility of distinguishing wines by their brand and provenance using pair-wise comparison of the classification function parameters for soils and wines produced from grape grown on those soils.

Egyptian Blue cakes from the Ayanis fortress (Eastern Anatolia, Turkey): micro-chemical and -structural investigations for the identification of manufacturing process and provenance

The microstructure and chemical composition of blue cakes, found during the archaeological excavation of the Ayanis fortress (Eastern Anatolia, Turkey), have been investigated by means of scanning electron microscopy combined with energy dispersive spectrometry (SEM–EDS), X-ray diffraction (XRD), micro-Raman (μ-Raman) and optical microscopy (OM) techniques. The analysis of the Ayanis cakes has shown the presence of Egyptian blue (i.e. CuCaOSi4O10, cuprorivaite), as the major component, intermixed with minor amount of other phases such as partially reacted quartz grains, an adherent glass phase and copper oxides. Since the finding of Egyptian Blue in Turkey has been never reported so far, great attention has been paid to its characterisation. The micro-chemical and micro-structural investigations of the Ayanis cakes have allowed a further insight into the manufacturing process and into the sources of the starting materials. The results of the characterisation have revealed some significant differences with respect to Egyptian blue cakes found in Egypt and Mesopotamia, as for instance the absence of tin excluded the use of bronze scraps or filings in their preparation differently from those produced in Egypt and Mesopotamia. Furthermore, some peculiarities of Egyptian blue found in Ayanis, as the detection of zinc in the cakes, allow to put forward the hypothesis of a local production considering that a large part of the bronze artefacts found at the Ayanis fortress is characterised by the presence of zinc as minor alloying element.

Professional minutia and their consequences: provenance, context, original identification, and anthropology at the Field Museum of Natural History, Chicago, Illinois

Historical settings structure how archivists and museum staff understand their work and how they apply relevant professional principles including the three core principles of provenance, context, and original identification. Their professional practices shape how the public understands or reads “original” artifacts and records. In helping to define what originals (artifacts and documents) are at a particular point in time, archivists and museum staff reinforce, support, or contradict theoretical paradigms, discourses, and social narratives on ethnicity, empire/internal colonialism, class, and gender among others. The article discusses two exemplary cases from the museum world that illustrate how the application of the three core principles is influenced by historical conditions and theoretical concepts and how these contingent applications influence what originals come to signify. In the first example, the theoretical concept of social evolution and the World Columbian Exposition in Chicago informed the founding, collecting, describing, and displaying of American Indian objects at the Field Museum of Natural History in 1894. Reflecting this, provenance, context, and original identifications were defined to mean different things for Euro-American versus American Indian objects and records, and Native Americans and others challenged these definitions and practices at the time. In the second example, the 1929–1933 making and displaying of the Hall of Races, a specific race anthropological understanding of race created unambiguous race anthropological provenance, context and original titles (identifications) for both the exhibit and individual race sculptures. By altering information concerning the three principles over the next 60 years, the Field Museum consciously destroyed the integrity of the originals and their meanings. The exhibit had become a political liability and the museum wanted to erase any trace of the race anthropological roots of the project and its sculptures. The article ends by asserting the contingency and importance of the three core principles for archivists and museum staff regardless of the format of the material involved and adds a few related observations for our contemporary hybrid, that means physical and digital, work world.

Forensic Assessment of Metal Contaminated Rivers in the 21st Century Using Geochemical and Isotopic Tracers

Documentation of contaminant source and dispersal pathways in riverine environments is essential to mitigate the potentially harmful effects of contaminants on human and ecosystem health, and is required from a legal perspective (particularly where the polluter pays principle is in effect) in assessing site liability. Where multiple natural and/or anthropogenic sources exist, identification of contaminant provenance has proven problematic, and estimated contributions from a specific source are often the subject of judicial debate. The past, current, and future use of geochemical and isotopic tracers in environmental forensic investigations of contaminant provenance, transport, and fate are analyzed herein for sediment-associated trace metals in riverine environments, particularly trace metals derived from mining and refining operations. The utilized methods have evolved significantly over the past four decades. Of primary significance has been the growing integration of geomorphic and stratigraphic techniques with the use of an increasing number of geochemical tracers including stable isotopes. The isotopes of Pb have been particularly well studied, and have been applied to a wide range of environmental media. Advances in analytical chemistry since the early 1990s have allowed for the precise characterization of other non-traditional stable isotopic systems within geological materials. The potential for using these non-traditional isotopes as tracers in river systems has yet to be adequately explored, but a number of these isotopes (e.g., Cd, Cu, Cr, Hg, Sb, and Zn) show considerable promise. Moreover, some of these isotopes (e.g., those of Cu, Cr, and Hg) may provide important insights into biogeochemical cycling processes within aquatic environments. This review suggests that future environmental forensic investigations will be characterized by an interdisciplinary approach that combines the use of multiple geochemical tracers with detailed stratigraphic, geomorphic, and hydrologic data, thereby yielding results that are likely to withstand the scrutiny of judicial review.

Isolation and characterization of microsatellites in a medicinal plant, Phyllanthus emblica (Euphorbiaceae)

Microsatellite markers were isolated and characterized in a medicinal plant, Phyllanthus emblica, to study population genetics for designing an effective in situ and ex situ conservation of genetic resources of the species. • Six microsatellite markers were developed using an enrichment and magnetic separation protocol. They were characterized in two natural populations of P. emblica. Out of the six microsatellites, five showed polymorphism, with the number of alleles ranging from four to seven. Observed and expected heterozygosities ranged from 0.360 to 0.760 and 0.499 to 0.806, respectively. • The five polymorphic microsatellite markers will be useful for studying the genetic structure, reproductive biology, and for identification of clones and provenances of this important medicinal plant.

Provenance of basaltic tephra from Vatnajökull subglacial volcanoes, Iceland, as determined by major- and trace-element analyses

The Holocene eruption history of subglacial volcanoes in Iceland is largely recorded by their tephra deposits. The numerous basaltic tephra offer the possibility to make the tephrochronology in the North Atlantic area more detailed and, therefore, more useful as a tool not only in volcanology but also in environmental and archaeological studies. The source of a tephra is established by mapping its distribution or inferred via compositional fingerprinting, mainly based on major-element analyses. In order to improve the provenance determinations for basaltic tephra produced at Grímsvötn, Bárdarbunga and Kverkfjöll volcanic systems in Iceland, 921 samples from soil profiles around the Vatnajökull ice-cap were analysed for major-element concentrations by electron probe microanalysis. These samples are shown to represent 747 primary tephra units. The tephra erupted within each of these volcanic system has similar chemical characteristics. The major-element results fall into three distinctive compositional groups, all of which show regular decrease of MgO with increasing K2O concentrations. The new analyses presented here considerably improve the compositional distinction between products of the three volcanic systems. Nevertheless, slight overlap of the compositional groups for each system still remains. In situ trace-element analyses by laser-ablation-inductively-coupled-plasma-mass-spectrometry were applied for better provenance identification for those tephra having similar major-element composition. Three trace-element ratios, Rb/Y, La/Yb and Sr/Th, proved particularly useful. Significantly higher La/Yb distinguishes the Grímsvötn basalts from those of Bárdarbunga and Rb/Y values differentiate the basalts of Grímsvötn and Kverkfjöll. Additionally, the products of Bárdarbunga, Grímsvötn and Kverkfjöll form distinct compositional fields on a Sr/Th versus Th plot. Taken together, the combined use of major- and trace-element analyses in delineating the provenance of basaltic tephra having similar major-element composition significantly improves the Holocene tephra record as well as the potential for correlations with tephra from outside Iceland.

Varietal heavy mineral analysis of sediment provenance, Lower Cretaceous Scotian Basin, eastern Canada

The origin of a major increase in sand supply in the Early Cretaceous of the Scotian Basin, offshore eastern Canada, has been investigated by analysis of heavy mineral varieties. The chemistry of detrital minerals from the Scotian Basin was compared with that of minerals from potential source rocks, sampled from older sedimentary successions, river sands and glacial tills on land. Heavy mineral varieties were established based on > 1000 high quality electron microprobe (EMP) analyses and used to classify heavy mineral types by Mineral Liberation Analysis (MLA), which uses a rapid scanning electron microscope particle analyser. Heavy mineral varieties were compared between the Cretaceous quartz arenites and subarkoses and samples from potential source areas. Different chemical varieties of the same mineral group have different grain size distributions, so that their relative modal abundances may be influenced by hydraulic sorting, but modal abundance of different varieties of tourmaline, garnet and spinel provides useful information. Widely used provenance-sensitive mineral ratios are difficult to interpret because of the abundance of polycyclic sources. Comparisons of the shape parameters of the individual mineral types are also useful for provenance identification. Aspect ratio in elongate grains, such as tourmaline and zircon, is a measure of polycyclic reworking, but is influenced by the initial shapes of minerals from different source rocks. Uniformity of varietal heavy minerals over a large area and stratigraphic range, and the covariance of spinel and zircon with quite different crystalline sources, indicate predominance of polycyclic sources to the Central Scotian Basin, probably principally from Carboniferous and Lower Paleozoic sandstones, in part sourced from western Newfoundland ophiolites. Heavy mineral varieties in the West Scotian Basin can be closely matched to sources in the adjacent Meguma Terrane of the Appalachians. All the data show that the sands of the Scotian Basin were derived from reworking of crystalline basement of the Appalachian orogen and its Paleozoic sandstone cover, uplifted during rifting of Iberia from the Grand Banks. There is no evidence of a significant supply of sand to the Scotian Basin from a proto-St Lawrence River.

Strontium-, carbon- and oxygen-isotope compositions of marbles from the Cycladic blueschist belt, Greece

AbstractThe Cycladic blueschist belt, Greece, is mostly submerged below sea level and regional correlations are difficult to establish. Marbles are widespread within the belt and locally used as marker horizons to subdivide monotonous schist sequences. However, owing to the lack of distinctive petrographic characteristics, the marbles have not been used for island-to-island correlations. This study aims to investigate the potential of Sr-, C- and O-isotope compositions of marbles as a tool for unravelling the litho- and/or tectonostratigraphic relationships across the Cycladic islands, and as a proxy for the time of sediment formation. For this purpose, we have studied metamorphic carbonate rocks from the islands of Tinos, Andros, Syros, Sifnos and Naxos. Identical87Sr/86Sr values for certain marble horizons occurring on Tinos, Andros and Sifnos are interpreted to document coeval regional carbonate precipitation. The87Sr/86Sr values of the apparently least altered samples intersect the seawater curve multiple times within the most likely time interval of original carbonate precipitation (< 240 Ma; as indicated by previously published ion probe U–Pb zircon data) and thus an unequivocal age assignment is not possible. Very broad temporal correlations are possible, but more subtle distinctions are not feasible. On Andros, the overlapping Sr-isotope values of marbles representing the lowest and highest parts of the metamorphic succession are in accordance with a model suggesting isoclinal folding or thrusting of a single horizon, or very fast sedimentation. In contrast, distinct87Sr/86Sr values for samples from Tinos, representing different levels of the metamorphic succession, suggest that these rocks represent a temporal succession and not the tectonic repetition of a single horizon. Based on Sr-, O- and C-isotope characteristics alone the time equivalence of marbles occurring on different islands could not be documented unambiguously. However, by using various combinations of these parameters, some occurrences can be discriminated from the overall sample population. The new data further accentuate the general potential of coupled Sr-, C- and O-isotope characteristics for identification of archaeological provenance and complement existing datasets for Aegean marbles.

The Application of Solution and Laser Ablation Based ICP-MS and Solution Based AES for the Provenance Determination of Selected Food and Drink Produce

The provenance identification of selected types of food and drink was undertaken from data obtained using both solution and laser ablation based inductively coupled plasma mass spectrometry (ICP-MS) and solution based inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis of selected food and drink materials (pork, wine, tea, coffee and olive oil). Quantitative determination of up to 55 elements was undertaken using solution based ICP- MS and AES while counts per second data for 49 elements was used for samples analyzed using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). ICP-AES was used to determine the concentrations of Na, K, Ca, Mg and Fe where appropriate. A quantitative analytical methodology for LA-ICP-MS analysis of olive oil was also developed and preliminary trials undertaken. Additional information, to establish more detailed geographic resolution in provenance determination, especially for tea and coffee (plantation of origin), was provided by the incorporation of data for light stable isotope distribution patterns ( 2 H (D), 13 C and 15 N). LA-ICP-MS was used for the direct analysis of olive oil and coffee beans. The use of laser ablation for the analysis of olive oil has the potential to overcome problems associated with both acid dissolution and thermal oxidation of this material, which are the traditional methods of sample dissolution and which either introduce significant contamination or cause the loss of volatile organo-metallic compounds that may be indicative for provenance determination. Results from the overall study indicated that it was possible not only to establish country of origin of the study materials but also in some cases to improve resolution of provenance to state of origin (wine and pork), and even plantation of origin (tea and coffee).

Archaeological applications of laser-induced breakdown spectroscopy: an example from the Coso Volcanic Field, California, using advanced statistical signal processing analysis

Over the past quarter century, multielement chemical analysis has become a common means for attributing the provenance of archaeological materials. The Coso Volcanic Field (CVF) in California, USA, contains at least 38 high-silica rhyolite domes, many of which contain obsidian glass that has been quarried for tools by the indigenous population for more than 12,000 years. Artifacts made from CVF obsidian are found throughout the southwestern United States and geochemical sourcing of CVF obsidian has been an important tool in understanding prehistoric Native American trading patterns. Laser-induced breakdown spectroscopy (LIBS) is a simple atomic emission spectroscopic technique that has the potential for real-time man-portable chemical analysis in the field. Because LIBS is simultaneously sensitive to all elements, a single laser shot can be used to record the broadband emission spectra, which provides a “chemical fingerprint” of a material. Single-shot broadband LIBS spectra were collected using a commercial benchtop LIBS system for 27 obsidian samples from major sites across the CVF and four additional sites in California and western Nevada outside of CVF. Classification of the samples was performed using partial least-squares discriminant analysis (PLSDA), a common chemometric technique suitable for performing regression on high-dimensional data. Provenance identification for the obsidian samples was evaluated for three separate labeling frameworks. The first framework consisted of a binary classification problem to distinguish CVF samples from non-CVF samples. The second approach focused on the CVF samples with labels that corresponded to the eight separate Coso sites encompassed by the 27 samples. In the third analysis, non-CVF samples were excluded, and the remaining 27 CVF samples were labeled based on groupings defined from previous major and trace element chemical studies, which reduces the number of possible classes from eight to four. Different aspects of the classifier setup considered in this study include the training/testing routine (a 27-fold leave-one-sample-out setup versus a simple split of the data into separate sets for training and evaluation), the number of latent variables used in the regression model, and whether PLSDA operating on the entire broadband LIBS spectrum is superior to that using only a selected subset of LIBS emission lines. The results point to the robustness of the PLSDA technique and suggest that LIBS analysis combined with the appropriate statistical signal processing has the potential to be a useful tool for chemical analysis of archaeological artifacts and geological specimens.

Coherent composition of glacial dust on opposite sides of the East Antarctic Plateau inferred from the deep EPICA ice cores

The dust provenance identification through isotopic and geochemical tracers focused mostly on ice cores drilled in the Pacific‐Indian sector of Antarctica, where a common provenance of dust from Southern South America during glacial ages was demonstrated. Conversely, in other areas of the East Antarctic Plateau as Dronning Maud Land provenance was deduced indirectly from back trajectory analyses and soluble chemistry records. In this work, we present the first comparison of major elemental composition of dust archived in two ice cores from opposite sides of Antarctica, in the framework of the EPICA Project. Mineral particles extracted from the EDC and EDML cores date back to glacial MIS 2, 4 and 6, over the last 200 kyr. Results reveal a coherent geochemical dust composition at both locations, providing experimental evidence of a common provenance over the wide area of East Antarctica during glacials, and key analytical constrains for atmospheric general circulation models.