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Early and Late Cretaceous alkaline and alkaline–carbonatitic complexes from southern Brazil are located along the main tectonic lineaments of the South America Platform. Calcium-, magnesium-, and ferrocarbonatites are well represented and frequently associated even in the same complex. Primary carbonates present significant variations in C–O isotopic compositions, which are mainly due to isotope exchange with H2O–CO2-rich hydrothermal fluids, whereas fractional crystallization or liquid immiscibility probably affects the δ18O and δ13C values by no more than 2δ‰. Our isotope exchange model implies that the most significant isotopic variations took place in a hydrothermal environment, e.g., in the range 400–80°C, involving fluids with the CO2/H2O ratio ranging from 0.8 to 1. Sr–Nd–Pb isotope systematics highlight heterogeneous mixtures between HIMU and EMI mantle components, similar to the associated alkaline rocks and the flood tholeiites from southern Brazil. In spite of the strong variation shown by C–O isotopes, Sr–Nd–Pb–Os isotopic systematics could be related to an isotopically enriched source where the chemical heterogeneities reflect a depleted mantle “metasomatized” by small-volume melts and fluids rich in incompatible elements. These fluids are expected to have promoted crystallization of K-rich phases in the mantle, which produced a veined network variously enriched in LILE and LREE. The newly formed veins (enriched component) and peridotite matrix (depleted component) underwent a different isotopic evolution with time as reflected by the carbonatites. These conclusions may be extended to the whole Paraná–Etendeka system, where isotopically distinct parent magmas were generated following two main enrichment events of the subcontinental lithospheric mantle at 2.0–1.4 and 1.0–0.5 Ga, respectively, as also supported by Re–Os systematics. The mantle sources preserved the isotopic heterogeneities over a long time, suggesting a nonconvective lithospheric mantle beneath different cratons or intercratonic regions. Overall, the data indicate that the alkaline–carbonatitic magmatism originated from a locally heterogeneous subcontinental mantle.

The Sr-isotope ratios of several samples from a natural and an agricultural soil from Ravenna were determined using aqua regia and the two-step sequential extraction. Results indicate that the two-step extraction can provide the researcher with wider and more precise information on Sr sources, thus being a more suitable methodology for achieving scientific goals than the aqua regia extraction. Lastly, the extracts of hydrochloric acid and aqua regia display similar ranges of δ87Sr, indicating that the two procedures provide comparable information on Sr sources.

Sr-Nd isotopes were applied for the first time to the study of several moss samples from a transect stretching through Romagna from the Apennines to the Adriatic sea coast. The isotopic data suggest that the mosses uptake Sr and Nd via atmospheric depositions from both marine carbonates and old siliceous crustal rocks. Anthropic pollution cannot be precisely evaluated because of the lack of univocal isotopic signature of the sources.

Sr-Nd isotopes were applied for the first time to the study of several moss samples from a transect stretching through Romagna from the Apennines to the Adriatic sea coast. The isotopic data suggest that the mosses uptake Sr and Nd via atmospheric depositions from both marine carbonates and old siliceous crustal rocks. Anthropic pollution cannot be precisely evaluated because of the lack of univocal isotopic signature of the sources., Les isotopes du Sr et Nd ont été appliqués pour la première fois à l’étude des échantillons de mousses pris en Romagne le long d’une section de la côte adriatique aux Apennins. Les données isotopiques suggèrent que les mousses captent Sr et Nd de la poussière atmosphèrique par deux sources, les carbonates marins et les roches de la croûte siliceuse. La pollution anthropique ne peut pas être évaluée certes, car elle n’a pas de signatures isotopiques typiques., Gli isotopi dello Sr e del Nd sono stati applicati per la prima volta allo studio di campioni di muschio prelevati da un transetto attraverso la Romagna esteso dal mare adriatico agli Appennini. I risultati suggeriscono che i muschi prendono Sr e Nd tramite la polvere atmosferica da due sorgenti rappresentate dai carbonati marini e dalle rocce silicatiche crostali. L’inquinamento antropico non può essere valutato con certezza perché non è caratterizzato da parametri isotopici univoci., EQA - International Journal of Environmental Quality; Vol 3 (2010); 9-14

The Sr-isotope ratios of several samples from a natural and an agricultural soil from Ravenna were determined using aqua regia and the two-step sequential extraction. Results indicate that the two-step extraction can provide the researcher with wider and more precise information on Sr sources, thus being a more suitable methodology for achieving scientific goals than the aqua regia extraction. Lastly, the extracts of hydrochloric acid and aqua regia display similar ranges of δ87Sr, indicating that the two procedures provide comparable information on Sr sources., Les rapports isotopiques du Sr ont été déterminés dans les échantillons d’un sol naturel et d’un autre agricole de la zone de Ravenne en utilisant l’aqua regia et l’extraction séquentielle. Les résultats indiquent que l’extraction séquentielle peut fournir une information plus large et plus détaillée sur les sources du Sr. Elle représente donc une méthodologie plus adaptée aux buts scientifiques que l’extraction avec aqua regia. Enfin, les extraits avec aqua regia et acide chlorhydrique fournissent des valeurs comparables de δ87Sr, indiquant que les deux procédures donnent des informations analogues sur les sources de Sr., Sono stati determinati i rapporti isotopici dello Sr di parecchi campioni di un suolo naturale e uno agricolo della zona di Ravenna usando aqua regia e l’estrazione sequenziale. I risultati indicano che l’estrazione sequenziale può fornire una più ampia e puntuale informazione sulle sorgenti dello Sr, essendo quindi una metodica più adatta a conseguire gli scopi scientifici di quanto non sia l’estrazione con aqua regia. Infine gli estratti in aqua regia e acido cloridrico forniscono valori simili di δ87Sr, indicando che le due procedure danno informazioni analoghe sulle sorgenti dello Sr., EQA - International Journal of Environmental Quality; Vol 4 (2010); 7-14

The Sr isotopic compositions of 11 wines from Romagna were determined with the aim of providing a new parameter to track the origin of these wines and serving for better trading. The 87Sr values measured ranged narrowly from -0.07 to +0.33 permil, in agreement with the provenance of the parent grapes from an area characterized by substantial uniformity of soil composition. However, so far, it is possible to make a preliminary distinction of the Sangiovese wines from the other wines analyzed because the former contain slightly more radiogenic Sr. This may reflect the different soil geology of vineyards, as the Sangiovese wines are made from grapes mainly growing on flysch soils, while the other wines are from grapes growing on sedimentary and alluvial Pliocene-Quaternary soils. The comparison of the data from Romagna wines with those of other Italian regions shows the potential of the 87Sr to characterize most of these products. However, the data are ambiguous for distinguishing the wines from vinyards growing on similar lithologies, i.e. soils developed on Late Cenozoic sedimentary rocks. The application of Sr isotopes may be a promising tool for setting the fingerprints of wines when combined with other isotopic and chemical parameters., La composition isotopique du Sr a été mesurée dans 11 vins de Romagne, parce que la détermination de ce paramètre peut être utile à tracer l’origine des produits pour une meilleure commercialisation. Les 87Sr mesurés se sont avérés homogènes au sein d'une faible amplitude de valeurs (-0.07 et +0.33 o/oo), en accord avec la provenance des raisins d’une zone caractérisée en grande partie par l’uniformité des sols. On peut distinguer de façon préliminaire, les vins Sangiovese des autres, parce que ces vins-ci contiennent plus de Sr radiogénique. Cela peut être expliqué par la différente composition géologique des sols, car les raisins de Sangiovese poussent surtout sur sols de flysch et, au contraire, les autres vins proviennent de terrains sédimentaires du Pliocène-Quaternaire. En comparant les données isotopiques des vins de Romagne et d’autre régions italiennes, il semble possible que le 87Sr soit un élément distinctif de la plus grande partie des vins, mais non de tous. Mais les données isotopiques sont ambiguës pour distinguer les vins de raisins développés sur sols issus de lithologies semblables, comme les roches sédimentaires du Cénozoïque supérieur. L’application des isotopes du Sr peut être un outil favorable pour définir les caractéristiques des vins, en conjonction avec d’autres paramètres isotopiques et chimiques., È stata determinata la composizione isotopica dello Sr di 11 vini della Romagna, perché la determinazione di questo parametro può essere utile a tracciare l’origine del prodotto per una migliore commercializzazione. I δ87Sr misurati sono risultati sostanzialmente omogenei, variabili tra -0,07 e +0.33 per mille, in accordo con la provenienza delle uve da un’area caratterizzata da sostanziale uniformità dei suoli. E’ comunque possibile in via preliminare distinguere i vini Sangiovese dagli altri analizzati perché i primi contengono Sr leggermente più radiogenico. Ciò può riflettere la differente geologia dei suoli, perché le uve del Sangiovese crescono prevalentemente su terreni flisciodi, laddove le uve degli altri vini si sviluppano generalmente su suoli sedimentari e alluvionali di età pliocenica-quaternaria. Inoltre dal confronto dei dati isotopici dei vini della Romagna e di altre regioni italiane si evince la possibilità che il δ87Sr sia un parametro distintivo, sebbene non in tutti i casi. Infatti i dati isotopici mostrano ambiguità per vini di uve che crescono su suoli sviluppatisi su simili litologie, cioè rocce sedimentarie tardo-cenozoiche. Tuttavia è possibile che l’applicazione degli isotopi dello Sr possa essere un promettente strumento di definizione della provenienza dei vini, in associazione con altri parametri isotopici e chimici., EQA - International Journal of Environmental Quality; Vol 7 (2011); 41-48

The Sr/Ca ratios and Sr-isotope ratios of bulk samples and acetate extracts from a soil profile developed on Pliocene marine clays near Radicofani, in southern Tuscany, were determined. The uniform Sr/Ca ratios in the soil indicated a uniform distribution of the two elements throughout the profile. In contrast, the lower Sr/Ca ratios of acetate extracts from the upper horizons of the soil suggest preferential removal of Sr relative to Ca, perhaps by the plants. These latter seem to accumulate more Sr than Ca during their lifetime. The δ87Sr of acetate extracts suggests that bulk Sr is provided by the calcite of the Mesozoic-Cenozoic sedimentary formations of southern Tuscany. A minor source of Sr, although subordinate, is represented by clastic albite. A grass sample growing on the soil contained the Sr uptaken from both sources., Les rapports Sr/Ca et les isotopes du Sr ont été déterminés dans des échantillons de sol et les fractions extraites avec l’acétate d’ammonium, d’un profil développé sur les argiles marines du Pliocène près de Radicofani, dans la Toscane méridionale. Les rapports uniformes Sr/Ca du sol indiquent une distribution uniforme des deux éléments le long du profil. Par contre, les rapports plus faibles des fractions acétate mesurés dans les horizons supérieurs du sol suggèrent un retrait préférentiel éloignement du Sr, probablement par la végétation. Il semble que les herbes accumulent plus Sr que de Ca pendant leur vie. Les valeurs de δ87Sr des fractions acétate suggèrent que la plupart du Sr est fournie par la calcite dérivée des formations sédimentaires mésozoϊques et cénozoϊques de la région. Une source mineure de Sr est représentée par l’albite clastique. Un échantillon d‘herbe ayant poussé sur le sol contenait du Sr dérivé de ces deux minéraux., Sono stati determinati i rapporti Sr/Ca e i rapporti isotopici dello Sr in campioni di suolo e negli estratti d’acetato di un profilo sviluppato sulle argille marine plioceniche presso Radicofani, nella Toscana meridionale. I rapporti uniformi Sr/Ca del suolo indicano una distribuzione uniforme dei due elementi nel profilo. Al contrario, i rapporti più bassi misurati nelle frazioni d’acetato degli orizzonti superiori del suolo suggeriscono l’allontanamento preferenziale dello Sr, probabilmente ad opera della vegetazione. Sembra che le erbe accumulino più Sr di Ca durante la loro vita. I valori di δ87Sr degli estratti d’acetato suggeriscono che la maggior parte dello Sr deriva dalla calcite delle formazioni sedimentarie meso-cenozoiche della regione. Una sorgente minore è costituita dall’albite clastica. Un campione di erba che cresce sul suolo contiene Sr derivato da ambedue i minerali., EQA - International Journal of Environmental Quality; Vol 5 (2010); 7-14

In the frame of a multidisciplinary project of research on the San Vitale Pinewood ecosystem, north of Ravenna, the Sr isotope study of a soil profile developed on an old coastal dune aiming at detecting the effect of salinization is presented. The Sr isotope ratios of the bulk soil samples decreased significantly from upper (0.717) to lower (0.712) horizons because of the abundant marine salts deposited by the brackish water present in the deep soil. While the main source of Sr in the upper horizons is the silicates, especially the feldspaths contained in the old dune sediments; in contrast, Sr in the lower horizons is significantly also of evaporitic origin (0.707-0.709). This latter is dominantly the strontium bio-available to the plants., Dans le cadre d’un projet multidisciplinaire de recherche sur le processus de salinisation des sols, nous présentons une application des isotopes du Sr à un profil de sol développé sur une ancienne dune côtière dans la Pinède S.Vitale, au nord de Ravenne. La composition isotopique du Sr dans les échantillons du sol tel quel diminue des horizons superficiels (0,717) aux horizons profonds (0,712) par suite de l’abondant dépôt de sels marins par l’eau saumâtre présente dans les horizons inférieurs du profil. Le strontium présent dans les horizons les plus superficiels provient des silicates de l’ancienne dune, en particulier des feldspaths, mais le strontium des horizons inferieurs provient en grade partie aussi du lessivage des évaporites (0,707-0,709). Le strontium biodisponible pour les plantes est surtout dérivé des évaporites., Nel quadro di uno studio multidisciplinare sui processi di salinizzazione che interessano i suoli della Pineta di san Vitale, a nord di Ravenna, viene presentato un esempio di applicazione degli isotopi dello Sr. La sua composizione isotopica nei campioni di suolo tal quale diminuisce significativamente dagli orizzonti superficiali (0,717) a quelli profondi (0,712), a causa della abbondante deposizione di sali marini ad opera dell’acqua salmastra presente nella parte bassa del profilo. Mentre lo Sr presente negli orizzonti superiori del suolo è essenzialmente quello dei silicati dell’antica duna, in particolare dei feldspati, lo Sr degli orizzonti inferiori deriva considerevolmente anche dai sali e minerali evaporitici (0,707-0,709). Lo Sr biodisponibile per le piante è essenzialmente quello derivato dagli evaporiti., EQA - International Journal of Environmental Quality; Vol 2 (2009); 73-77

Sr/Ca ratios, and Sr and Nd isotopes, were determined in aqua regia extracts from three urban and agricultural soils from Ravenna. Sr/Ca ratios suggested preferential retention of Sr in the agricultural soils during the weathering of bedrock minerals. Despite of the different land use, the three soils displayed similar isotopic ranges, suggesting common sources for the two elements, likely represented by old marine carbonates and crustal silicates. The Nd isotopes of the urban park topsoil suggest some contamination by the soot of car exhausts., Les rapports Sr/Ca et les isotopes du Sr et du Nd ont été déterminés dans les extraits avec aqua regia de trois sols agricoles et résidentiels dans la zone de Ravenne. Les rapports Sr/Ca suggèrent la rétention préférentielle du Sr dans les sols agricoles pendant l’altération des minéraux. Nonobstant leur utilisation différente, les sols ont des valeurs isotopiques semblables, qui suggèrent des sources communes pour les deux éléments, représentées par d’anciens carbonates marins et des silicates de la croûte terrestre. Les horizons, les plus superficiels du sol du parc urbain sont probablement affectés par une pollution de Nd dérivé des émissions de voitures., Sono stati determinati i rapporti Sr/Ca e i rapporti isotopici di Sr e Nd in estratti di aqua regia di tre suoli interessati da uso agricolo e residenziale della zona di Ravenna. I rapporti Sr/Ca suggeriscono la ritenzione preferenziale dello Sr nei suoli agricoli durante l’alterazione dei minerali. Nonostante il differente uso, i suoli hanno rapporti isotopici simili, suggerendo che Sr e Nd derivano da sorgenti comuni, rappresentate da carbonati marini antichi e silicati crostali. Gli orizzonti più superficiali del suolo del giardino pubblico mostrano una probabile presenza di Nd derivato dalle emissioni di scarico dei veicoli., EQA - International Journal of Environmental Quality; Vol 4 (2010); 53-62