Fabio Tateo

Mode and tempo of the Paleocene-Eocene thermal maximum in an expanded section from the Venetian pre-Alps

Mode and tempo of an expanded Paleocene Eocene Thermal Maximum section in the Venetian Pre-Alps

Interplay between tectonics and glacio-eustasy: Pleistocene succession of the Crotone basin, Calabria (southern Italy)

On a global scale, the Crotone basin preserves one of the best-developed and most complete Pleistocene marine records available in outcrop, as important as those in California, New Zealand, and Japan. A deformed, markedly cyclothemic, lower to middle Pleistocene succession is present in the territory of San Mauro Marchesato (Crotone area, southern Italy), showing an overall shallowing trend from slope mudstones to marginal marine and continental deposits. Preservation and high resolution of cyclothems occurred through the interaction between high-amplitude relative sea-level fluctuations, a particular pattern of differential subsidence due to intrabasinal tectonics, and high rates of sediment supply. The studied succession was laid down in the Crotone basin under an extensional tectonic regime, following a major, middle Pliocene contractional phase probably of transpressional nature. Two major unconformities, locally accompanied by angular discordances, occur within the succession. The former, centered at ca. 1.2 Ma, is thought to reflect the opening of the San Mauro subbasin within the Crotone basin in the early Pleistocene, following dextral transtensional motion along north- to north-northeast–trending faults. The latter, with a hiatus lasting from ca. 0.65 to 0.45 Ma, may reflect the decoupling of the Calabrian block with respect to Adria and Sicily, allowing further advancing of the Calabrian arc in the Ionian area, where subduction could continue until the present time. The lower part of the succession (the H. sellii and “large Gephyrocapsa ” Zones, from ca. 1.67 to ca. 1.23 Ma) consists of slope to outer-shelf monotonous mudstones and is bounded at the top by the first unconformity, whose gap suppresses the upper part of to locally the entire “large Gephyrocapsa ” Zone (1.608–1.235 Ma) and the lower part of the “small Gephyrocapsa ” Zone (1.235–0.96 Ma). A number of cyclothems developed in an outer- to inner-shelf environment within the “small Gephyrocapsa ” Zone. Biomagnetostratigraphic constraints strongly support a correlation between the condensed sections of cyclo thems and MIS (marine isotope stage) 33 to MIS 25. From the base of the P. lacunosa Zone (at ca. 0.96 Ma) upward, the succession rapidly becomes sand dominated, a change that can be confidently correlated with the major climatic shift associated with MIS 24 to MIS 22. In the following succession, two tephra layers, named “Pitagora ash” and “Parmenide ash,” provide mappable isochronous surfaces across the subbasin. The sedimentary record is remarkably cyclo themic, characterized by a stack of simple or composite, seaward-prograding, sand- dominated tongues and intervening aggradational deposits related to transgressive-deepening episodes. The cyclothems can be confidently correlated with the oxygen isotope record up to the Matuyama-Brunhes inversion, i.e., up to MIS 19, whereas the stratigraphic record postdating MIS 19 has poorer chronological constraints. Dating is provided by tracing the Parmenide ash in the deeper-water coeval succession of the southern part of the Crotone basin, where the deposits including the ash can be correlated by means of nannofossil biostratigraphy with termination V (transition from MIS 12 to MIS 11). The second unconformity marks an abrupt increase in the proximal character of the sedimentary deposits forming the cyclothems, which incorporate increasing amounts of marginal-marine to continental deposits in the upper part of the subbasin infill. Several lines of direct and indirect evidence indicate that, in spite of the dramatic role of tectonics in shaping stratigraphic architecture, the roles of tectonics and eustasy can be disentangled, owing to the different time scales of the tectonic events and the high-frequency, high-amplitude glacio- eustatic Pleistocene cycles. Interaction between intrabasinal tectonics and high rates of sediment supply allowed forced regressive and possibly also lowstand systems tracts to be preserved in some cyclothems, particularly in the lower part of the succession, an unusual fact in shelf deposits. Considering the far younger age of marine terraces on the Ionian side of Calabria when compared to the Tyrrhenian side, it is thought that, during ongoing subduction of the Ionian crust, a wave of uplift and related extensional tectonics migrated southeastward in the rear of the frontal accretionary wedge.

The use of pelitic raw materials in thermal centres: Mineralogy, geochemistry, grain size and leaching tests. Examples from the Lucania area (southern Italy)

The pelitic materials used in two important thermal centres of southern Italy have been studied from mineralogical, geochemical and granulometrical points of view, both in natural conditions and after maturation. These data can be used as an inorganic compositional reference compared with a wider database of pelitic sediments cropping out in the area. Prospecting criteria matching the compositional data of raw materials, mineralogic considerations and geochemical data concerning the amount of hazardous trace elements, have been proposed. Besides the traditional criteria, the role of toxic elements was also considered. Reproducing the active mechanism during therapeutic treatments, the leaching tests were performed, and the mobility of the same element, regarded as dangerous, was emphasised. The release of the toxic elements and some important therapeutic properties depend mainly on clay mineralogy. Therefore, the contribution of mineralogy and geochemistry in the development of thermal medicine is underlined.

Integrated stratigraphy of the Oligocene pelagic sequence in the Umbria-Marche basin (northeastern Apennines, Italy): A potential Global Stratotype Section and Point (GSSP) for the Rupelian/Chattian boundary

The Oligocene represents an important time period from a wide range of perspectives and includes significant climatic and eustatic variations. The pelagic succession of the Umbria-Marche Apennines (central Italy) includes a complete and continuous sequence of marly limestones and marls, with volcaniclastic layers that enable us to construct an integrated stratigraphic framework for this time period. We present here a synthesis of detailed biostratigraphic, magnetostratigraphic, and chemostratigraphic studies, along with geochronologic results from several biotite-rich volcaniclastic layers, which provide the means for an accurate and precise radiometric calibration of the Oligocene time scale. From this study, the interpolated ages for the Rupelian/Chattian stage boundary, located in the upper half of Chron 10n at meter level 188 in the Monte Cagnero section, and corresponding to the O4/O5 planktonic foraminiferal zonal boundary, are 28.36 Ma (paleomagnetic interpolation), 28.27 ± 0.1 Ma (direct radioisotopic dating), and 27.99 Ma (astrochronological interpolation). These ages appear to be slightly younger than those reported in recent chronostratigraphic time scale compilations. The Monte Cagnero section is a potential candidate for defining the Chattian Global Stratotype Section and Point (GSSP) and some reliable criteria are here proposed for marking the Rupelian/Chattian boundary according to International Union of Geological Sciences (IUGS) recommendations.

Mineralogy and geochemistry of herbalist's clays for internal use : simulation of the digestive process

Abstract The laboratory simulation of the digestive process has been carried out considering 14 different herbalists clays for internal use found on the Italian market. The digestion has approximately used a two-stage experiment: the first one involving acidic solutions (matching the stomach environment), the other one reproducing bile–pancreas juices. The clay composition of a few samples is rather selected (mainly kaolinite and illite) and several are poly-mineralic clays, mainly with phyllosilicates, calcite, dolomite and quartz. One effect of the clay digestion is the dissolution of carbonates, developing a complete transfer of Ca and Mg from the solid to the digestive solutions and an increase of the pH values. The relationship between carbonates and pH can be obtained considering the buffer exerted by carbonates, which results in a bimodal distribution of pH, from about 1 to 3 and from about 5 to 6. The concentration of several chemical elements occurring into the final digestive solution is pH-dependent (the lower the pH, the higher the concentration; for example Al, P, Be, Sc, V, Fe, Cu, Zn, Ga, Ba, La, Nb, REE); on the other hand, chemical elements hosted into carbonates (for example Ca, Sr, Mg) are larger in higher pH solutions. To verify possible hazardous effects on human health, the chemical element concentration into the final solution has been compared to the maximum daily dose available from the drinking water regulation. Among elements not hosted into the carbonates, Al relatively shows high concentration, which can be justified by the occurrence of abundant clay minerals into the solids. Since the toxic effects of Al have been recently stressed, the silicate mineral digestion (and clays in particular) should be considered with caution, especially if the clay is carbonate-free. In this case, the pH stays at low values, increasing the Al solubility. Other hazardous chemical elements reach rather low levels, except for Ba, which is considered very toxic in soluble form. Additional precautionary advice arise from the recognition of serpentine minerals and free silica, due to the relationship between these minerals and human pathologies. Taking into account that hazardous chemical elements have been detected with solutions and that mineralogical risk is far from being excluded, it appears that a regulation will be necessary, if we consider the natural remedy market growing.

Geochemistry of two peats suitable for medical uses and their behaviour during leaching

Abstract The compositional characteristics of two peats, from Austria and Italy, have been studied. The Massaciuccoli peat shows a high quantity of trace elements (Br, Cd, Mo, Se, U, As and Sb) with respect to the average shale, whereas the Neydharting peat contains more Br, Se and U. Since the therapeutic properties of peats are broad and interesting, the mobility of trace elements (As, Cd, Hg, Pb, Sb, Se, Te and Tl) used for pelotherapy, during water leaching and after Na exchange, have been checked. The data concerning the leaching procedure indicate that the analysed peats are rather stable materials under laboratory conditions. Although the concentration of some toxic elements (As, Se, Cd and Hg) in bulk peats are of the same order of magnitude as in muds used in pelotherapy, the release after similar leaching is lesser. The higher release from muds could be explained by the high exchange capacity of smectite minerals. These minerals are characterised by low cation selectivity because the chemical interactions between smectite and sorbed species is mainly ionic. On the other hand, the cation–organic matter interactions can establish a higher degree of covalent bonds, that are more stable during the interactions developed with leaching. An additional possibility can be considered taking into account the genetic conditions of peat formation. In the upper part, the acidic and oxidising conditions cause the depletion of mobile elements. This process can be seen as a natural cleaning, which occurs under relatively strong conditions compared to the use during medical treatments.

Contribution of grain size and compositional data from the Bengal Fan sediment to the understanding of Toba volcanic event

Abstract Toba Tephra layers in cores from the Bengal Fan have been studied to characterize their granulometric, mineralogic and geochemical features. The layers are silt-sized sediments with no significant non-volcanic contamination. The samples are very homogeneous: glass shards have moderate hydration (about 6% water), a calc-alkaline character and a rhyolitic composition. The major and trace element compositions indicate an orogenic affinity and coincide with literature data for the youngest Toba Tephra level (YTT, 75 ka). X-ray diffraction (XRD) data indicate that the glass is the dominant phase, with minor feldspar, biotite and quartz. The grain size analyses of the beds show discontinuous vertical variation and no linear trends from south to north over about 1500 km. The vertical granulometric gap of the layers probably represents a single pyroclastic emplacement unit subjected to pre-depositional particle aggregation.

Orbital control on pelagic clay sedimentology; the case of the late Albian Amadeus Segment (central Italy)

The Amadeus Segment which falls within the Oceanic Anoxic Event 1c, is a composite stratigraphic interval of late Albian age, composed by frequent alternation of black shales characterised by organic carbon content usually lower than 1% and carbonate-richer sediments. Geochemical and clay mineral signatures indicate a coarser grain size for the black shales, and geochemical data from literature indicate a continental origin of the organic matter. Most of the geochemical variables analyzed show a record which follows an orbital cyclicity, with the exception of Mn and Ba, whose mobility after burial was identified by independent compositional criteria. The spectral analysis succeeded in identifying such compositional peculiarities, and also enabled to correlate the Amadeus Segment with the Segment-1 of the nearby Piobbico Core. The Milankovitch cyclicity (low eccentricity and obliquity) deeply affects the sedimentation of the Amadeus Segment, because orbital frequencies characterize the distribution of foraminiferal and compositional variables, which are both controlled by organic productivity and by detrital supply (dilution effect excluded). The high frequency changes from carbonate-rich layers to black shales are interpreted as changes in oceanographic regimes which in turn caused variations in the dispersal regime of continental inputs and in productivity.

Mineralogical and morphological investigation of kidney stones of a Mediterranean region (Basilicata, Italy)

Kidney stones are a very frequent finding in southern Italy, but stone analysis is not routinely performed. However, it is an important requirement not only for a successful treatment of this disease, but also for the prophylaxis to prevent any recurrence. We therefore set out to analyze 80 kidney stones collected from Basilicata Region (Southern, Italy). X-ray powder diffraction as well as optical and scanning electron microscopy and petrographic thin section analysis have been applied in order to determine the mineralogical and morphological compositions. The internal structure and the relation between major and minor components have facilitated the classification of the kidney stones according to a detailed scheme. As it is known from other country, calcium oxalate stones were the most frequent (59%) [39% mainly composed of whewellite, CaC₂O₄*H₂O and 29% is mainly made of weddellite, CaC₂O₄*2H₂O]. Uric acid stones were abundant too (18%). Calcium phosphate and cystine stone were less. The results of the observations of kidney stones in thin petrographic sections led to the identification of more cores in the same whewellite kidney stones. In some kidney stones the core is not situated in the central zone, which represents the point of attachment on kidney wall. Basilicata kidney stone prevalence is different from the average prevalence determined in other Mediterranean areas. The comparison showed that calcium oxalate stones seem to be more frequent, and there is a high prevalence of uric acid kidney stones and a lower prevalence of phosphate kidney stones, especially hydroxyapatite. The relative increase frequency of uric acid stones in the northern part of the Region may be due to high-purine diets and softness water consumption.

X-ray microdiffraction and urine: A new analysis method of crystalluria

The qualitative and quantitative analyses of crystalluria have clinical significance in the diagnosis and prognosis of urolithiasis. The aim of this paper is to provide a new accurate methodology to get qualitative and quantitative data on urine particulate in patients with renal stone disease.The procedure involves a urine collection, the separation of the solid residual by centrifugation, and its analysis by X-ray diffraction, utilizing a micro-diffractometer in order to analyze very low amounts of residual. The spectrum obtained was converted into 2 θ -I profiles and quantitatively refined by Rietveld method. The proposed methodology has the advantage to accurately quantify all crystalline phases and the amorphous component of the urine; anyway urine samples have to be centrifuged and analysed as soon as possible, because the quantitative results obtained by the X-ray microdiffraction showed that after some days and at room temperature urine increased significantly both amorphous and crystalline phases.