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Marble quarries exploited in antiquity of the Denizli and Karacasu Basins (Turkey) were characterized by their petrography, carbon and oxygen isotopes, and cathodoluminescence. This study is an useful contribution for provenance studies of archeological artifacts composed of unknown marble. Marble quarries from the Hierapolis, Laodikeia, and Aphrodisias territories were considered; they constitute a homogeneous group of marble extraction districts. Collectively, they were among the most important sites for marble exploitation throughout antiquity from southwestern Anatolia, where only Afyon and Ephesus, which have already been studied extensively, were more important. In spite of that, the exportation of these marbles in ancient times has not yet been demonstrated. This is partially because their identification has never been fully addressed scientifically. Petrography, isotopes, and cathodoluminescence techniques used together are effective in discriminating among the study marbles. This could facilitate the determination of the provenance of these marbles in local monuments and artifacts. However, it could be difficult to determine the marble provenances in cases where a larger set of possible provenances should be taken into consideration.

Stable isotope analysis in the reconstruction of human palaeodiets can yield clues to early human subsistence strategies, origins and history of farming and pastoralist societies, and intra- and intergroup social differentiation. In the last 10 years, the method has been extended to the pathological investigation. Stable isotope analysis to better understand a diet-related disease: celiac disease in ancient human bones was carried out. To do this, we analyzed the nitrogen and carbon isotopic composition of human (n = 37) and faunal (n = 8) bone remains from the archaeological site of Cosa at Ansedonia, on the Tyrrhenian coast near Orbetello (Tuscany), including the skeletal remains of a young woman (late 1st century-early 2nd century Common Era [CE]) with morphological and genetic features suggestive of celiac disease. We compared the young woman's isotopic data with those of other individuals recovered at the same site but from two later time periods (6th century CE; 11-12th century CE) and with literature data from other Italian archaeological sites dating to the same period. Her collagen δ(13) C and δ(15) N values differed from those of the samples at the same site, and from most but not all of the contemporary sites. Although the woman's diet appears distinct, chronic malnutrition resulting from severe malabsorption of essential nutrients due to celiac disease may have affected the isotopic composition of her bone collagen.

International audience; The chemistry and isotope ratios of He, C (δ13C) and H (δD) of free gases collected in the San Vittorino plain, an intramontane depression of tectonic origin, were determined to shed light on mantle degassing in central Italy. The C isotopic composition of CO2 (δ13C-CO2 −2.0‰ to −3.8‰) and He isotope ratios (R/RA 0.12-0.27) were used to calculate the fraction of CO2 originating from mantle degassing vs. sedimentary sources. The results show that CO2 predominantly (average of 75%) derives from the thermo-metamorphic reaction of limestone. Between 6% and 22% of the CO2 in the samples derives from organic-rich sedimentary sources. The mantle source accounts for 0-6% of the total CO2; however, in two samples, located in proximity to the most important faults of the plain, the mantle accounts for 24% and 42%. The presence of faults and fractures allows upward gas migration from a deep source to the Earth's surface, not only in the peri-Tyrrhenian sector, as generally reported by studies on natural gas emissions in central Italy, but also in the pre-Apennine and Apennine belts. Isotope ratios of CH4 (δ13C-CH4 −6.1‰ to −22.7‰; δD-CH4 −9‰ to −129‰) show that CH4 does not appear to be related to mantle or magma degassing, but it is the product of thermal degradation of organic matter (i.e. thermogenic origin) and/or the reduction of CO2 (i.e. geothermal origin). Most of the samples appear to be affected by secondary microbial oxidation processes.

The microbial diversity of moonmilk, a hydrated calcium carbonate speleothem, was evaluated from two Italian caves to provide context for the food web of highly-specialized troglobitic beetles, Cansiliella spp. (Leptodirinae), with distinctive carbon and nitrogen isotope values indicative of a novel food source. The moonmilk and associated percolating waters had low to no extractable chlorophyll, with an average organic C:N ratio of 9, indicating limited allochthonous input and a significant contribution from microbial biomass. The biomass from moonmilk was estimated to be ~10 4 micro- and meiofaunal individuals per m 2 and ~10 7 microbial cells/ml. Proteobacteria dominated the 16S rRNA gene sequences retrieved from the moonmilk from both caves. The distribution of other proteobacterial classes and phyla in the moonmilk were statistically similar to each other, even though the two caves are geographically separated from each other. Comparing the moonmilk gene sequences to sequences from previously described environmental clones or cultured strains revealed the uniqueness of the moonmilk habitat, as ~15% of all of the moonmilk sequences were more closely related to each other than to sequences retrieved from any other habitat. However, comparative analyses confirmed that as much as ~34% of the clones sequences were also closely related to environmental clones and cultured strains derived from soil and freshwater habitats, which is likely due to the fact that the putative inoculation source for the moonmilk bacterial communities is from overlying soil and percolating fluids from the surface. Prior to our studies of Cansiliella spp., moonmilk has not been considered a food source for cave animals. Our findings provide unique insight into moonmilk microbial diversity that could reveal the underpinnings of the moonmilk carbon and nitrogen cycle that influences the isotopic composition and the morphological adaptations of the troglobitic beetles associated with the moonmilk. calcium carbonate; microorganisms; food web; nitrogen cycling; beetles

A characterization of medium enthalpy geothermal resources has been carried out in the Southern Apennines "Guardia Lombardi" site (Campania Region, Italy) within the framework of the Vigor Project. Due to the intense hydrocarbon exploration carried out in Italy since the '50, a wide public dataset of well data and seismic reflection profiles is available for the study site. Moreover, a scientific cooperation with the ENI Italian Oil Company has been established in order to access to more detailed dataset also including wells information and core samples. A three-dimensional geological model of the reservoir-caprock system has been developed through an integrated interpretation of the available geological, geophysical, hydrogeological and geochemical information in the study area. The geothermal reservoir of "Guardia Lombardi" site is constituted by the Cretaceous-Eocene fractured shallow water carbonates belonging to the Apulian platform. Such units have been structured in a buried antiformal stack during the Apennine orogenesis. The reservoir fluids are mainly composed of CO2, which rests above of brackish water in the central part of the deep carbonatic aquifer culmination (i.e., Monte Forcuso 1 well). Conversely along the flanks of the buried anticline (e.g., Bonito 1 Dir, Ciccone 1 wells) the reservoir fluids consist of saline water, not showing any free gas phase. The temperature of this fluids recorded into the reservoir are 120-125°C at the depth of about 3000 m below the ground level (e.g. Bonito 1 well). Given the quite good permeability of the fractured carbonate rocks, numerical simulation performed in this work estimated that a water production of about 13.5-20 kg/s might be achieved according to the chosen technical solution (a single production well vs production- reinjection doublet). Results confirm that the "Guardia Lombardi" site represents an interesting area for the exploitation of this medium enthalpy geothermal resource.

The aim of this study is to apply an integrated approach to determine nitrate sources and fate in the alluvial aquifer of the River Vibrata (Abruzzi, central Italy) by coupling the Isotope and the Component approaches. Collected data include concentration and nitrogen isotope composition of groundwater samples from the alluvial aquifer and nitrogen loads arising from agricultural and non-agricultural sources. The adopted methodology identified synthetic fertilizers as main sources of nitrate in the Vibrata alluvial aquifer. At the catchment scale, two different zones have been identified: the Upper Valley, where infiltration to groundwater is dominant and nitrogen easily migrates into the aquifer; in this area, nitrate content in groundwater is stable and normally higher than EU requirements. Moreover, streamwaters are fed by groundwater with a nitrate content likely lowered by denitrification processes occurring in the hyporheic zone. In the Lower Valley, runoff processes dominate and the nitrate content in surface waters is higher. Nevertheless, groundwater is locally affected by denitrification that breaks down the nitrate content, which often reaches values consistent with law limits. © 2012 Springer-Verlag.

The Ipanema alkaline-carbonatitic complex is part of the Meso-Cenozoic alkaline magmatism located within the southeastern part of the Brazilian Platform. Drill-core and field sampling have indicated the occurrence of glimmerites, with subordinate shonkinites (mela-syenites), clinopyroxene-bearing glimmerites, diorites and syenites. The glimmerites are cross-cut by lamprophyric dykes and calciocarbonatites. Fenitization has deeply affected the country rocks, originating dioritic and syenitic rocks. The Ipanema rocks show a distinct potassic affinity. The initial Sr-Nd- isotopic composition of the Ipanema rocks (Sr-87/Sr-86 = 0.70661-0.70754 and Nd-143/Nd-144 = 0.51169-0.51181) is similar to that of tholeiitic and potassium-rich-alkaline rocks of the Eastern Paraguay. Stable isotope data for the Ipanema calciocarbonatite suggest interaction with fluids at temperatures typical of hydrothermal stages, as hypothesized for other carbonatite complexes from southeastern Brazil. The chemical differences between the lamprophyre, glimmerites, carbonatites, apatitites and magnetitites, and the absence of marked REE enrichment in the evolved lithologies, all indicate that fractional crystallization and accumulus of liquidus phases in a magma reservoir, likely coupled with liquid immiscibility processes, may have played an important role in the genesis of the Ipanema rocks.

The study examines the food webs of macroinvertebrates along a gradient from the sandy shore to a dune slack in the retrodune. The study was conducted at the Maremma Regional Park in an area subjected to beach progradation. Transects with pitfall traps were set perpendicular to the sea to capture macroinvertebrates, whereas vegetation biomass was evaluated using quadrats. Marine allochthonous material was also examined. Stable isotopes of delta(13)C and delta(15)N were analysed both in plants and macroinvertebrates of marine and terrestrial origins. Hierarchical cluster analysis was used to group species with similar values. Multi-source mixing models were used to analyse the contribution of carbon of marine origin to the diets, to calculate trophic levels and to estimate the diets of certain species. The results indicate a decrease in the contribution of marine carbon in the diets of terrestrial macroinvertebrates along the sea land axis.

A study was conducted on a Tyrrhenian sandy beach ecosystem to examine habitat partitioning of macroinvertebrates in relation to the abiotic factors and to the vegetation and to assess links with trophic webs. The study site was located in the Maremma Regional Park, in an area where the beach was undergoing a process of aggradation and thus was in a continuous dynamic state. The site was characterised by a dune slack that could be periodically flooded by heavy rain or invaded by marine water during violent sea storms. Monthly surveys were carried out for an entire year along two transects regularly set from the shoreline to the retrodune. Plants were assessed through quadrat sampling whereas macroinvertebrates were caught with pitfall traps perpendicular to the shoreline. Species diversity (? and ? diversity), richness and abundance were calculated together with mean zonations for both plants and terrestrial invertebrate species. Using Hierarchical cluster analysis plants were grouped into two clusters according to the abiotic factors whereas macroinvertebrates into four, according to abiotic factors and to the vegetation. For the most abundant species isotopic signature of ?13C and ?15N were assessed and cluster analysis was again preformed. Multi-source mixing models were used to identify trophic levels and the relative contribution of each food sources to the diets of each group of macroinvertebrates. The results of the annual ? diversity value indicated a very rich invertebrate community highly correlated to the complexity of the habitat and a ? diversity value that showed changes in the composition of the community every 40 m. The influence of marine subsides in the food web decreased at increasing distance from the sea and distinctive food webs were found according to the species zonation patterns. Some species mainly depended upon marine subsides (wrack debris), others, although inhabiting beach areas, were tied to both marine and terrestrial food sources whereas dune slack species were linked to terrestrial items. The work showed that in a spatially limited but complex environment, as is a beach - dune - slack system, marine wracks mainly subsided macroinvertebrates species of the eulittoral and contributed very little to the energy budget of more terrestrial species.

Magma–carbonate rock interaction is investigated through a geochemical and Sr–Nd–O isotope study of granular lithic clasts (ejecta) from the Alban Hills ultrapotassic volcano, Central Italy. Some samples (Group-1) basically represent intrusive equivalents of Alban Hills magmas. A few samples (Group-2) are ultramafic, have high MgO (∼30 to 40 wt%) and δ18O‰, and originated by accumulation of mafic phases that crystallised from ultrapotassic melts during assimilation of dolomitic rocks. Group-3 ejecta consist of dominant K-feldspar, and show major element compositions similar to phonolites, which, however, are absent among the Alban Hills volcanics. Finally, another group (Group-4) contains corroded K-feldspars, surrounded by a microgranular to porphyritic matrix, made of igneous minerals (K-feldspar, foids, clinopyroxene, phlogopite) plus wollastonite, garnet, and some cuspidine. Group-4 ejecta are depleted in SiO2 and enriched in CaO with respect to Group-3. The analysed ejecta have similar 143Nd/144Nd (0.51204–0.51217) as the Alban Hills lavas, whereas 87Sr/86Sr (0.70900–0.71067) is similar to lower. Whole rocks δ18O‰ ranges from +7.0 to +13.2, reaching maximum values in ultramafic samples. A positive correlation with CaO is observed in single rock groups. Large Ion Lithophile Element (LILE) abundances and REE fractionation are generally high, and extreme values of Th, U and LREE are found in some Group-3 and Group-4 rocks. Mineralogical, petrological and geochemical data reveal extensive interaction between magma and carbonate wall rocks, involving both dolostones and limestones. These processes had dramatic effects on magma compositions, especially on phonolites, which were transformed to foidites. Evidence of such a process is found in Group-4 samples, in which K-feldspar is observed to react with a matrix that represents strongly undersaturated melts formed by interaction between silicate magma and carbonates. Trace element data also testify to a very important role for F–CO2–H2O–S fluids during magma–wall rock interaction. Fluid transfer was responsible for extreme enrichments in Th, U, and LREE especially observed in Group-3 and Group-4 rocks. Implications of these processes for potassic magma evolution in Central Italy are discussed.

The Kenyan coast is characterized by a raised fossil reef complex cut by a series of morphological terraces. Shallow subtidal coralgal facies containing Tridacna gigas shells are found at different heights along the coast. Alpha-spectrometric U-series methods were applied to 18 T. gigas samples from different locations along this reef complex with an elevation range from 0 to 15 m above present sea level to obtain chronological information. Apparent U–Th ages, based on the assumption of closed system behaviour, correspond to early marine isotope stage (MIS) 5 (n = 17) and MIS 7 (n = 1). However, initial 234U/238U activity ratios exhibit a wide range, in many cases much greater than present seawater, which is likely to be associated with diagenetic alteration and migration of U-series isotopes. For this reason, we attempted a form of open system isochron dating after separating the Tridacna samples into three different groups on the basis of current elevation and distribution along the coast. An ‘isochron’ age of 120 ± 4 ka (1 sigma) was obtained for the higher elevation group, placed in the terraced central coastal area; another age, statistically undistinguishable from the previous one, of 118 ± 7 ka (1 sigma) was obtained for the group confined along the northern coast. These two groups correspond to a transgressive–regressive cycle connected to the maximum sea level highstand during the MIS 5e. A third ‘isochron’ age of 100 ± 4 ka (1 sigma) was obtained for the group confined along the southern coast, encompassing part of the isotopic substages MIS 5c and d. Based on these data, and on the ecology of T. gigas whose optimal present-day depth range can be considered of 3–10 m below sea level, a maximum tectonic coastal uplift rate of between, respectively, 0.12 and 0.18 mm a-1 was calculated for the period since formation of these shells, and then the paleobathymetry of Tridacna facies has been inferred.

[1] Recent studies have proposed that magma reservoirs crystallized to a virtually rigid crystal-mush can be partially remelted by diffusion of hot fluids. We show that for a crystal mush with the composition of a K-trachyte from the Campanian Ignimbrite (CI) Eruption, remelting can occur without a significant increase of the magma temperature, but simply by diffusion of H2O by the magmatic gases feeding the system. The CI origin is not the issue here, but rather the chemical and physical behavior of an almost solidified magma mass left over in a reservoir after a major eruption. To test our hypothesis, we run high pressure/high temperature laboratory experiments to study the kinetics of water diffusion, together with thermodynamics and fluid diffusion modelling. For small diffusivities, or large diffusion time, the remelting mechanism proposed above needs to be replaced by other processes as gas percolation or intrusion of a magmatic mass.

Structural investigations, integrated with X-ray diffraction, fluid inclusion microthermometry and oxygen-stable isotope analyses are used to reconstruct the deformation history and the palaeo-fluid circulation during formation of the low-grade, turbidite-dominated Early Palaeozoic Robertson Bay accretionary complex of north Victoria Land (Antarctica). Evidence for progressive deformation is elucidated by analysing the textural fabric of chronologically distinct, thrust-related quartz vein generations, incrementally developed during progressive shortening and thickening of the Robertson Bay accretionary complex. Our data attest that orogenic deformation was mainly controlled by dissolution-precipitation creep, modulated by stress- and strain-rate-dependent fluid pressure cycling, associated with local and regional permeability variations induced by the distribution and evolution of the fracture network during regional thrusting. Fracture-related fluid pathways constituted efficient conduits for episodic fluid flow. The dominant migrating fluid was pre-to-syn-folding and associated with the migration of warm (160-200 � C) nitrogen- and carbonic (CO2 and CH4)-bearing fluids. Both fluid advection and diffusive mass transfer are recognized as operative mechanisms for fluid-rock interaction and vein formation during continuous shortening. In particular, fluid-rock interaction was the consequence of dissolution-precipitation creep assisted by tectonically driven cooling fluids moving through the rock section as a result of seismic pumping. The most likely source of the migrating fluids would be the frontal part of the growing accretionary complex, where fluids from the deep levels in the hinterland are driven trough channelization operated by the thrust-related fracture (fault) systems.

Quantitative signal processing methods have been applied to a δ180 profile for a land-based stratigraphic section, extending from the upper part of lower Pleistocene to the lower part of middle Pleistocene. The section is well exposed with a continuous succession of muds and muddy silts, about 400 m thick, located in the southernmost part of Bradano Trough, near Montalbano Jonico in Basilicata (south Italy). The sampled part of the section is about 240 m thick, in which a foram benthic species (Cassidulina carinata) is continuously available for oxygen isotope ratio measurements. The aim of the data treatment is to discover how much of the Earth's orbital periodic movements, precession and obliquity, which represent the dominant periodicities in paleoclimatic variations from the base of the Pleistocene until 0.735 Myr BP, are responsible for the oscillations observed in the oxygen-18 record of the Montalbano Jonico section. A time framework of the section was constructed on the basis of calcareous nannofossil biostratigraphic analyses, preliminary magnetostratigraphic results and oxygen isotope correlation with the record from DSDP s607 (isotope data collected in the NOAA World Data Center). The resulting time-scale extends from 1.15 to 0.74 Myr. Power spectrum analysis was performed on the isotope data to illuminate the most important periodicity components of the Montalbano Jonico record. The periodic components of 41,000 and 21,000 yr are present in this record; the former associated with periodic changes in the tilt of Earth's axis and the latter with periodic changes with the precession of the equinoxes, as predicted by the astronomical theory of ice ages. They are, however, not the most important components of the power spectrum, in which a lower frequency component contains most of the variance. This low-frequency component is centered at a period around 208,000 yr. This periodicity seems not to be attributable to any known astronomical or paleoclimatic phenomenon. An attempt was made to verify if this periodicity was due to the composite effect of precession and obliquity signals together at different frequencies from their forcing frequencies. In order to investigate this effect, isotope data have been parameterized in terms of a sum of simple functions of precession and obliquity signals with unknown coefficients. The coefficients are estimated from the time series with the assumption that the best coefficients are those which minimize the ‘noise’ i.e. the difference between the data function and the precession and obliquity functions. Cross-spectra analyses were also performed on the data and the precession signal and on the data and the obliquity signal. The power spectrum of the residual ‘noise’ functions and the cross-spectra demonstrate that precession and obliquity signals are not in phase with the data at their forcing frequencies and so damp. The precession and obliquity signals were then shifted towards lower frequencies at equally spaced lags, the resultant ‘noise’ power spectra were plotted for every combination of lags of precession and obliquity. The results of this data processing demonstrate that it is possible to have a combination of precession and obliquity cyclicities that could be responsible for the signal with 208 kyr periodicity.