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Tephrochronology (from tephra , Gk ‘ashes’) is a unique stratigraphic method for linking, dating, and synchronizing geological, palaeoenvironmental, or archaeological sequences or events. As well as utilizing the Law of Superposition, tephrochronology in practise requires tephra deposits to be characterized (or ‘fingerprinted’) using physical properties evident in the field together with those obtained from laboratory analyses. Such analyses include mineralogical examination (petrography) or geochemical analysis of glass shards or crystals using an electron microprobe or other analytical tools including laser-ablation-based mass spectrometry or the ion microprobe. The palaeoenvironmental or archaeological context in which a tephra occurs may also be useful for correlational purposes. Tephrochronology provides greatest utility when a numerical age obtained for a tephra or cryptotephra is transferrable from one site to another using stratigraphy and by comparing and matching inherent compositional features of the deposits with a high degree of likelihood. Used this way, tephrochronology is an age-equivalent dating method that provides an exceptionally precise volcanic-event stratigraphy. Such age transfers are valid because the primary tephra deposits from an eruption essentially have the same short-lived age everywhere they occur, forming isochrons very soon after the eruption (normally within a year). As well as providing isochrons for palaeoenvironmental and archaeological reconstructions, tephras through their geochemical analysis allow insight into volcanic and magmatic processes, and provide a comprehensive record of explosive volcanism and recurrence rates in the Quaternary (or earlier) that can be used to establish time–space relationships of relevance to volcanic hazard analysis. The basis and application of tephrochronology as a central stratigraphic and geochronological tool for Quaternary studies are presented and discussed in this review. Topics covered include principles of tephrochronology, defining isochrons, tephra nomenclature, mapping and correlating tephras from proximal to distal locations at metre- through to sub-millimetre-scale, cryptotephras, mineralogical and geochemical fingerprinting methods, numerical and statistical correlation techniques, and developments and applications in dating including the use of flexible depositional age-modelling techniques based on Bayesian statistics. Along with reference to wide-ranging examples and the identification of important recent advances in tephrochronology, such as the development of new geo-analytical approaches that enable individual small glass shards to be analysed near-routinely for major, trace, and rare-earth elements, potential problems such as miscorrelation, erroneous-age transfer, and tephra reworking and taphonomy (especially relating to cryptotephras) are also examined. Some of the challenges for future tephrochronological studies include refining geochemical analytical methods further, improving understanding of cryptotephra distribution and preservation patterns, improving age modelling including via new or enhanced radiometric or incremental techniques and Bayesian-derived models, evaluating and quantifying uncertainty in tephrochronology to a greater degree than at present, constructing comprehensive regional databases, and integrating tephrochronology with spatially referenced environmental and archaeometric data into 3-D reconstructions using GIS and geostatistics.

International audience; A recent survey in Mu Pon village, south of Mawlamyaing in the Mon State, revealed extensive looting in several areas. One large pit had contained, in addition to a reported thousands of beads, a group of broken tubes and fragments that the villagers had not been able to sell. We examined over 600 specimens, most directly related to glass bead production, and selected a representative group of 131 samples for chemical analysis by LA-ICPMS in an attempt to get some idea of the date and possible importance of the site. Just over half of the samples were potash glass, indicating a probable Southeast Asian origin, with most of the remainder moderate-to-high alumina soda glass typical for South Indian production; exceptionally, there were also two fragments of Roman natron glass. The materials included just two bracelet fragments, identical typologically and chemically to those produced at Khao Sam Kaeo in peninsular Thailand. By comparison with glass from other sites in Myanmar and Thailand, we conclude that this Mu Pon glass represents the remains of bead production from the last century BCE to the first few centuries CE, making Mu Pon by far the earliest documented glass bead manufacturing site in Myanmar, active at the same time as such sites as Phu Khao Thong and Kapoe in Ranong Province, Thailand. These results provide strong evidence that Mu Pon was economically and technologically integrated into early long-distance exchange networks that included both South India and the rest of Southeast Asia.

Arapucandere is one of a number of similar Cu–Zn–Pb ± Au–Ag epithermal deposits in the Biga Peninsula, which are mineralogically and tectonically similar. Fluid inclusions have very low salinities between 1.7 and 0 wt.% NaCl and a wide range of temperatures from ~ 360 to 160 °C. There was extensive boiling and “flashing” of the hydrothermal fluids which initiated mineral deposition. The range of temperatures is consistent with emplacement of the veins at ~ 700 m depth, with the pressure decreasing from near lithostatic to near hydrostatic and a decrease in temperature to ~ 250 °C due to adiabatic expansion of the fluids. There is evidence of a limited amount of boiling, but the temperature and pressure decrease was close to the liquid–vapour curve. Flashing of the fluids was caused by sudden drops to sub-hydrostatic pressures and even lower temperatures. Mineralization was caused by these pressure related temperature decreases as there is no evidence of cooling and dilution of the ore-fluids. δ 34 S values of sulphides indicate a magmatic source but the more negative than usual values also suggest boiling affected isotopes. δD and δ 18 O of the fluids indicate a mixing between meteoric waters and magmatic fluids, with the large range of δD due to boiling. LA-ICP-MS analyses of fluid inclusions reveal high Cu–Zn–Pb concentrations in the fluids, despite their low salinity, transported as chloride complexes. Exceptional pressure and temperature decrease causing the fluids to “flash” was likely to have been in response to earthquakes.

Arapucandere is one of a number of similar Cu-Zn-Pb Au-Ag epithermal deposits in the Biga Peninsula, which are mineralogically and tectonically similar. Fluid inclusions have very low salinities between 1.7 and 0 wt.% NaCI and a wide range of temperatures from -360 to 160 degrees C. There was extensive boiling and "flashing" of the hydrothermal fluids which initiated mineral deposition. The range of temperatures is consistent with emplacement of the veins at similar to 700 m depth, with the pressure decreasing from near lithostatic to near hydrostatic and a decrease in temperature to similar to 250 degrees C due to adiabatic expansion of the fluids. There is evidence of a limited amount of boiling, but the temperature and pressure decrease was close to the liquid-vapour curve. Flashing of the fluids was caused by sudden drops to sub-hydrostatic pressures and even lower temperatures. Mineralization was caused by these pressure related temperature decreases as there is no evidence of cooling and dilution of the orefluids. delta S-34 values of sulphides indicate a magmatic source but the more negative than usual values also suggest boiling affected isotopes. 81) and delta O-18 of the fluids indicate a mixing between meteoric waters and magmatic fluids, with the large range of 81) due to boiling. LA-ICP-MS analyses of fluid inclusions reveal high Cu-Zn-Pb concentrations in the fluids, despite their low salinity, transported as chloride complexes. Exceptional pressure and temperature decrease causing the fluids to "flash" was likely to have been in response to earthquakes. (C) 2014 Elsevier B.V. All rights reserved.

This paper presents the results of a petrographic and geochronological investigation of the Furquim Quartzite (FQ) to establish its stratigraphic correlation to quartzitic units of the Quadrilátero Ferrífero (QF) province. The Quartzite comprises a ca. 20km long and 1-6km wide ridge overlying discordantly the Archean to Paleoproterozoic gneissic basement and rocks of the Archean Rio das Velhas Supergroup between the city Mariana and the town Furquim, southeast of the QF. Despite the discordant contacts, previous field-based stratigraphic studies considered the Furquim Quartzite as part of the Archean Maquiné Group – top unit of the Rio das Velhas Supergroup. U-Pb zircon geochronology via LA-ICP-MS identified several detrital populations ranging from Paleoproterozoic to Archean age. The youngest population of 2087±19 Ma defines the maximum age for the sedimentation of the precursor sandstone. This age can be correlated to be the age of the youngest zircon population of the Itacolomi Group quartzites in the QF. Thus, in contrast to previous studies, the results indicate that the FQ is an eastern extension of the Itacolomi Group, the youngest unit of the Paleoproterozoic Minas Supergroup.

In the Arapuçandere LS-IS epithermal deposit in western Turkey, either well crystallised euhedral quartz or milky amorphous silica occurrences are associated with the precious and base-metal mineralisation. This study has determined the relative importance of the processes precipitating both of these in relation to the deposition of the ore. Analysis by LA-ICPMS of euhedral quartz and amorphous silica show that the latter is associated with much higher metal concentrations and suggests that the process responsible is more important for deposition of ore in the deposit. Mineralisation at Kumarlar and Koru may be similar. Slow cooling precipitates euhedral quartz and some ore but flashing of hydrothermal fluids causes drastic decreases in both T and P, sufficient to quantitatively deposit base metals and Au. In amorphous silica bands base metals reach concentrations of 1000?s of ppm compared with a few 10?s ppm in euhedral quartz; Au can reach over 1 ppm compared with a few 10?s ppb in quartz. The drastic pressure change from lithostatic to sub-hydrostatic could reasonably be caused by opening of faults and fractures by seismic events.

The breccia-hosted epithermal Au-Ag deposit of Rosia Montana is located 7 km northeast of Abrud, in the northern part of the South Apuseni Mountains, Romania. Estimated total reserves of 214.91 million metric tons (Mt) of ore at 1.46 g/t Au and 6.9 g/t Ag (10.1 Moz of Au and 47.6 Moz of Ag) make Rosia Montana one of the largest gold deposits in Europe. At this location, Miocene calc-alkaline magmatic and hydrothermal activity was associated with local extensional tectonics within a strike-slip regime related to the indentation of the Adriatic microplate into the European plate during the Carpathian orogenesis. The host rocks of the magmatic complex consist of pre-Mesozoic metamorphosed continental crust covered by Cretaceous turbiditic sediment (flysch). Magmatic activity at Rosia Montana and its surroundings occurred in several pulses and lasted about 7 m.y. Rosia Montana is a breccia-hosted epithermal system related to strong phreatomagmatic activity due to the shallow emplacement of the Montana dacite. The Montana dacite intruded Miocene volcaniclastic material (volcaniclastic breccias) and crops out at Cetate and Cârnic Hills. Current mining is focused primarily on the Cetate open pit, which was mapped in detail, leading to the recognition of three distinct breccia bodies: the dacite breccia with a dominantly hydrothermal matrix, the gray polymict breccia with a greater proportion of sand-sized matrix support, and the black polymict breccia, which reached to the surface, contains carbonized tree trunks and has a dominantly barren clastic matrix. The hydrothermal alteration is pervasive. Adularia alteration with a phyllic overprint is ubiquitous; silicification and argillic alteration occur locally. Mineralization consists of quartz, adularia, carbonates (commonly Mn-rich), pyrite, Fe-poor sphalerite, galena, chalcopyrite, tetrahedrite, and native gold and occurs as disseminations, as well as in veins and filling vugs within the Montana dacite and the different breccias. The age of mineralization (12.85 ± 0.07 Ma) was determined by 40 Ar- 39 Ar dating on hydrothermal adularia crystals from vugs in the dacite breccia in the Cetate open pit. Microthermometric measurements of fluid inclusions in quartz phenocrysts from the Montana dacite revealed two fluid types that are absent from the hydrothermal breccia and must have been trapped at depth prior to dacite dome emplacement: brine inclusions (32–55 wt % NaCl equiv, homogenizing at T h > 460°C) and intermediate density fluids (4.9–15.6 wt % NaCl equiv, T h between 345°–430°C). Secondary aqueous fluid inclusion assemblages in the phenocrysts have salinities of 0.2 to 2.2 wt percent NaCl equiv and T h of 200° to 280°C. Fluid inclusion assemblages in hydrothermal quartz from breccias and veins have salinities of 0.2 to 3.4 wt percent NaCl equiv and T h from 200° to 270°C. The oxygen isotope composition of several zones of an ore-related epithermal quartz crystal indicate a very constant δ 18 O of 4.5 to 5.0 per mil for the mineralizing fluid, despite significant salinity and temperature variation over time. Following microthermometry, selected fluid inclusion assemblages were analyzed by laser ablation-inductively coupled-plasma mass spectrometry (LA-ICPMS). Despite systematic differences in salinity between phenocryst-hosted fluids trapped at depth and fluids from quartz in the epithermal breccias, all fluids have overlapping major and trace cation ratios, including identical Na/K/Rb/Sr/Cs/Ba. Consistent with the constant near-magmatic oxygen isotope composition of the hydrothermal fluids, these data strongly indicate a common magmatic component of these chemically conservative solutes in all fluids. Cu, Pb, Zn, and Mn show variations in concentration relative to the relatively non-reactive alkalis, reflecting the precipitation of sulfide minerals together with Au in the epithermal breccia, and possibly of Cu in an inferred subjacent porphyry environment. The magmatic-hydrothermal processes responsible for epithermal Au-Ag mineralization at Rosia Montana are, however, not directly related to the formation of the spatially associated porphyry Cu-Au deposit of Rosia Poieni, which occurred about 3 m.y. later.

The elemental composition of European hake otoliths was analyzed at the core, settlement mark and otolith edge zones corresponding to the periods of pelagic early life stage, settlement to the bottom, and juvenile life, respectively. Barium, Sr, Mg, Mn and Ca were measured using LA-ICPMS on the sagitta otoliths of hake sampled in 6 different Western Mediterranean areas, separated by tens to hundreds of kilometers. The otolith edge, which should have incorporated the water mass signal of the sampling area, showed a high degree of overlap between geographical areas. This precluded the discrimination of geographically distinct groups. However, there was a clear ontogenetic signal in all the fish, with higher Sr:Ca in the otolith core. Ba:Ca was higher at the settlement mark, while Mn:Ca was overlapped with the core values. The otolith edge had lower ratios for all elements except for Mg. The conflicting effects of the ontogenic patterns and the inconclusive allocation of a geographical signal at the edge, precluded to assign individual hake to a natal origin based on the composition of the core and settlement mark zones. Our results may be explained by high mobility of the juvenile hake in this area of the Mediterranean, or by the relative homogeneity in the water masses for the four elements considered in this study. While this subset is useful for distinguishing major water masses or regional differences between, for example, the Atlantic and the Mediterranean, a larger set of elements could be needed for smaller-scale studies. © 2014 Elsevier B.V., This work is a result of the MICINN Project IDEADOS (Ref. No.: CTM2008-04489-C03/MAR). The salary of SPM is funded by the Spanish Ministry as part of the program MICINN-PTA (PTA2010-03812). The SPIRE Grant (No.: 719022) and Bergen University are thanked for the support to the first author

Alzheimer's disease (AD) is the leading cause of dementia in the elderly, affecting over 27 million people worldwide. AD represents a complex neurological disorder which is best understood as the consequence of a number of interconnected genetic and lifestyle variables, which culminate in multiple changes to brain structure and function. These can be observed on a gross anatomical level in brain atrophy, microscopically in extracellular amyloid plaque and neurofibrillary tangle formation, and at a functional level as alterations of metabolic activity. At a molecular level, metal dyshomeostasis is frequently observed in AD due to anomalous binding of metals such as Iron (Fe), Copper (Cu), and Zinc (Zn), or impaired regulation of redox-active metals which can induce the formation of cytotoxic reactive oxygen species and neuronal damage. Metal chelators have been administered therapeutically in transgenic mice models for AD and in clinical human AD studies, with positive outcomes. As a result, neuroimaging of metals in a variety of intact brain cells and tissues is emerging as an important tool for increasing our understanding of the role of metal dysregulation in AD. Several imaging techniques have been used to study the cerebral metallo-architecture in biological specimens to obtain spatially resolved data on chemical elements present in a sample. Hyperspectral techniques, such as particle-induced X-ray emission (PIXE), energy dispersive X-ray spectroscopy (EDS), X-ray fluorescence microscopy (XFM), synchrotron X-ray fluorescence (SXRF), secondary ion mass spectrometry (SIMS), and laser ablation inductively coupled mass spectrometry (LA-ICPMS) can reveal relative intensities and even semi-quantitative concentrations of a large set of elements with differing spatial resolution and detection sensitivities. Other mass spectrometric and spectroscopy imaging techniques such as laser ablation electrospray ionization mass spectrometry (LA ESI-MS), MALDI imaging mass spectrometry (MALDI-IMS), and Fourier transform infrared spectroscopy (FTIR) can be used to correlate changes in elemental distribution with the underlying pathology in AD brain specimens. Taken together, these techniques provide new techniques to probe the pathobiology of AD and pave the way for identifying new therapeutic targets. The current review aims to discuss the advantages and challenges of using these emerging elemental and molecular imaging techniques, and highlight clinical achievements in AD research using bioimaging techniques.

This study was performed to assess the role of nitrogen (N) rate and application time in combination with zinc (Zn) and iron (Fe) supplement in soil and foliage at booting stage of wheat (Triticum aestivum var. Krabat) for augmentation of protein, Zn and Fe in grain. Eighty four plastic pots of wheat containing 8 plants in each pot were grown in a climatically controlled growth room. The rates of N supply were 28.57, 42.86 and 57.14 mg N kg-1 soil, equivalent to 80, 120 and 160 kg N ha-1, respectively and for Zn and Fe, the rate was 10 mg kg-1 soil and additional 30% through foliar spray at the designated N treatments, a total of 21 treatments. Plants missed tillering reducing overall grain and straw yields. Grain and straw yield pot-1, 1000 grains weight, number of grains pot-1, whole grain protein content, concentration and total uptake of Zn and Fe in grains were determined. Analysis of variance demonstrated that soil applied N at sowing interacted often with Zn-Fe- treatments resulting differences in number of grains pot-1, straw yield, grain Fe- concentration and uptake of Zn and Fe in grain. A tendency of higher yield was seen when increasing N rate at sowing was applied but the tendency was reduced at higher dose (160 kg N ha-1 in this study). Relatively higher grain yield, protein content and the uptake of Zn and Fe in grain were obtained at split N equivalent to 160 kg N ha-1 (applying 70% of allocated N at sowing and 30% at stem elongation). But lower N rates at sowing resulted in reduced grain yield with higher concentrations of Zn and Fe in grain. At soil plus foliar supply of zinc sulfate (ZnSO4) and ferric ethylenediamine tetraacetic acid (Fe-EDTA) together enhanced grain protein content, concentration of Zn and Fe up to 46% and 64% and their total uptake in grain by 35% and 42%. For the localization of Zn and Fe in grain, LA-ICPMS and MA-XRF were used. Scanning of half grain along the crease pointed co-localization of Zn and Fe at germ, crease and aleurone. Split application of N with sufficient dose at sowing and stem elongation or beyond in combination with soil plus foliar application of Zn and Fe can be a good agricultural practice to enhance protein, Zn and Fe content in wheat. Key words: Zinc and iron uptake, nitrogen fertilization, foliar spray of zinc and iron, laser ablation-inductively coupled plasma-mass spectrometry (LA-ICPMS), wheat, wheat grain protein, grain components. 2014-12-15

Deccan Trap flood basalt volcanism reached its peak 65.5 (+/- 1) million years ago, giving rise to a 2.7 km thick lava pile that formed the Western Ghats range near Mumbai. The total duration of this activity cannot be constrained better than +/- 1 Ma by conventional Ar-dating techniques. It is also difficult to know whether there were short bursts of tremendous volcanic activity within that period which could have significantly impacted global climate. Here we employ diffusion relaxation modeling of Sr-87/Sr-86 zoning in plagioclase to obtain a better resolution on the life cycle of a magma chamber in order to provide a minimum constraint on the duration of the Western Ghats volcanic episode. The analyzed crystals are 2-5 cm long and occur in so-called Giant Plagioclase Basalt flows that mark the tops of the oldest formations of the Western Ghats. In the formation studied, such crystals may have recorded the life cycle of the magma chamber that fed the preceding flows. Our diffusion modeling yields 780 years for the maximum residence time for 5 cm long plagioclase crystals in the magma chamber and a mean growth rate of 2.03 Chi 10(-10) cm s(-1). Assuming continuous crystal growth while the underlying pile was being emplaced gives us a combined maximum rate of 0.13 m yr(-1) for incubation and extrusion of the lava. Using this rate we estimate that the peak volcanic activity lasted a minimum of 21,100 years. A short duration for the Deccan would preclude AFC contamination processes during emplacement of the bulk of Deccan lavas. (C) 2013 Elsevier Ltd. All rights reserved.

The study of fluid inclusions in high-grade rocks is especially challenging as the host minerals have been normally subjected to deformation, recrystallization and fluid-rock interaction so that primary inclusions, formed at the peak of metamorphism are rare. The larger part of the fluid inclusions found in metamorphic minerals is typically modified during uplift. These late processes may strongly disguise the characteristics of the “original” peak metamorphic fluid. A detailed microstructural analysis of the host minerals, notably quartz, is therefore indispensable for a proper interpretation of fluid inclusions. Cathodoluminescence (CL) techniques combined with trace element analysis of quartz (EPMA, LA-ICPMS) have shown to be very helpful in deciphering the rock-fluid evolution. Whereas high-grade metamorphic quartz may have relatively high contents of trace elements like Ti and Al, low-temperature re-equilibrated quartz typically shows reduced trace element concentrations. The resulting microstructures in CL can be basically distinguished in diffusion patterns (along microfractures and grain boundaries), and secondary quartz formed by dissolution-reprecipitation. Most of these textures are formed during retrograde fluid-controlled processes between ca. 220 and 500 °C, i.e. the range of semi-brittle deformation (greenschist-facies) and can be correlated with the fluid inclusions. In this way modified and re-trapped fluids can be identified, even when there are no optical features observed under the microscope. peerReviewed

This paper newly reports results of LA-ICPMS U-Pb dating for 282 zircon crystals separated from a Middle Miocene adakite in Cerro Pampa, southern Argentine Patagonia. With the exception of one spot age, 174 of the U-Pb concordia ages are markedly older (>94 Ma) than the cooling ages of the adakite magma (ca. 12 Ma). The presence of numerous exotic zircon crystals indicates that the adakitic magma carries up information related to the crustal components during its ascent through the entire crust underneath Cerro Pampa. The obtained concordia ages of exotic zircons, 94-1335 Ma, are divisible into five groups having distinctive peaks on a population diagram. The first (94-125 Ma) and second age groups (125-145 Ma) correspond to the age of plutonic activities that formed the main body of the South Patagonian Batholith. The third to fifth groups respectively correspond to activities of the El Qumado-Ibañez volcanic complex (145-170 Ma), plutonic rocks scarcely exposed in Central Patagonia (170-200 Ma), and the Eastern Andean metamorphic complex of Late Paleozoic to Early Mesozoic ages (200-380 Ma). Our data suggest that the crust underneath Cerro Pampa was formed mostly after 380 Ma, the majority forming during the Early Cretaceous to Middle Jurassic. The processes of crustal development ceased for ca. 80 m.y. until the activity of the Cerro Pampa adakite in ca. 12 Ma. In contrast to the existence of numerous Archaean-Palaeoproterozoic exotic zircons in Mesozoic plutonic rocks distributed in Andean Cordillera at around 46°S, no evidence was found for Archaean-Paleoproterozoic crust on the Cerro Pampa region at 48°S. This evidence suggests that two crusts must have aggregated along a boundary between 46°S and 48°S with the continental margin of Gondwana during Late Paleozoic times, as part of the amalgamation of Pangea. Fil: Orihashi, Yuji. The University of Tokyo. Earthquake Research Institute; Japón Fil: Anma, Ryo. University of Tsukuba. Graduate School of Life and Environmental Sciences; Japón Fil: Motoki, Akihisa. Rio de Janeiro State University. Departamento de Mineralogia e Petrologia Ígnea; Brasil Fil: Haller, Miguel Jorge F.. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Hirata, Daiji. Kanagawa Prefecture Museum of Natural History; Japón Fil: Iwano, Hideki. Kyoto Fission-Track; Japón Fil: Sumino, Hirochika. University of Tokyo. Graduate School of Science. Geochemical Research Center; Japón Fil: Ramos, Victor Alberto. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Geología. Laboratorio de Tectónica Andina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos; Argentina

The Estremoz Anticline in the Ossa-Morena Zone (SW Iberia) includes upper Ediacaran detrital rocks unconformably overlain by lower Cambrian detrital and carbonate rocks. The spectra of detrital zircon U–Pb ages dominated by Cryogenian and Ediacaran ages (with a typical gap in Mesoproterozoic ages) of the upper Ediacaran greywackes and lower Cambrian arkosic sandstones indicate provenance from sources placed near or at the North-Gondwana margin. These late Ediacaran and early Cambrian basins developed in a paleoposition close to the West African Craton and related to a long-lived Neoproterozoic magmatism (c. 850–700 Ma — Pan-African suture; c. 700–635 Ma — early Cadomian arc; and c. 635–545 Ma — late Cadomian arc). The rhyolites of the Volcanic–Sedimentary Complex of Estremoz whose stratigraphic position so far has been a controversy, yielded an upper Cambrian age (Furongian) at about 499 Ma indicating that carbonate production was episodic in SW Iberia during the Cambrian. This new evidence should be taken into account in the reshaping of paleogeographic reconstruction models that have erroneously insisted on placing Iberia at southerly cold water higher latitudes (> 60°S) during the Furongian.

High spatial resolution, quantitative chemical imaging is of importance to various scientific communities, however high spatial resolution and robust quantification are not trivial to attain at the same time. In order to achieve microscopic chemical imaging with enhanced quantification capabilities, the current study links the independent and complementary advantages of two micro-analytical techniques – Synchrotron Radiation-based micro X-ray Fluorescence (SR-microXRF) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS). A cross-calibration approach is established between these two techniques and validated by one experimental demonstration. In the presented test case, the diffusion pattern of trace level Cs migrating into a heterogeneous geological medium is imaged quantitatively with high spatial resolution. The one-dimensional line scans and the two-dimensional chemical images reveal two distinct types of geochemical domains: calcium carbonate rich domains and clay rich domains. During the diffusion, Cs shows a much higher interfacial reactivity within the clay rich domain, and turns out to be nearly non-reactive in the calcium carbonate domains. Such information obtained on the micrometer scale improves our chemical knowledge concerning reactive solute transport mechanism in heterogeneous media. Related to the chosen demonstration study, the outcome of the quantitative, microscopic chemical imaging contributes to a refined safety assessment of potential host rock materials for deep-geological nuclear waste storage repositories.

Information about dispersal scales of fish at various life history stages is critical for successful design of networks of marine protected areas, but is lacking for most species and regions. Otolith chemistry provides an opportunity to investigate dispersal patterns at a number of life history stages. Our aim was to assess patterns of larval and post-settlement (i.e. between settlement and recruitment) dispersal at two different spatial scales in a Mediterranean coastal fish (i.e. white sea bream, Diplodus sargus sargus) using otolith chemistry. At a large spatial scale (similar to 200 km) we investigated natal origin of fish and at a smaller scale (similar to 30 km) we assessed "site fidelity" (i.e. post-settlement dispersal until recruitment). Larvae dispersed from three spawning areas, and a single spawning area supplied post-settlers (proxy of larval supply) to sites spread from 100 to 200 km of coastline. Post-settlement dispersal occurred within the scale examined of similar to 30 km, although about a third of post-settlers were recruits in the same sites where they settled. Connectivity was recorded both from a MPA to unprotected areas and vice versa. The approach adopted in the present study provides some of the first quantitative evidence of dispersal at both larval and post-settlement stages of a key species in Mediterranean rocky reefs. Similar data taken from a number of species are needed to effectively design both single marine protected areas and networks of marine protected areas.

Hyperaccumulator plants are complex family characterized by taking up high amounts of heavy metals in their roots, translocating them to the shoot to be finally accumulated in above-ground organs, especially leaves. One of their principal interests is due to the possibility of using this type of plants for phytoremediation of contaminated or natural metal-rich soils. A new approach to quantify locally metals by LA-ICP-MS technique in these plants is presented using external calibration with addition of yttrium as internal standard with SRM NIST of tomato pressed pellets. On the other hand, a study of the metal distribution in Arabidopsis halleri leaves is performed by the same technique and elemental mapping is compared for fresh and freeze-dried leaves, young and mature leaves as well as for thin sections.

In this thesis otolith microchemistry analyses were used to gain insights into the individual life history and stock characteristics of three fish species from the Baltic Sea - the European eel Anguilla anguilla, the Atlantic cod Gadus morhua and the thicklip grey mullet Chelon labrosus. The special hydrographic environment of the world’s largest brackish water system provides promising conditions for the use of otolith elemental analysis to investigate individual migration patterns and stock structures of fish. Here, it was used to gain information with relevance for stock management of fish species that differ widely in their biology, ecology and stock structure. It was investigated whether individual continental migratory history affects health and spawner quality of the European eel. Otolith strontium (Sr) composition was used to identify characteristic migration patterns. Results show that the muscle fat contents of silver eels with strictly catadromous life cycles are significantly reduced compared to silver eels that never entered freshwaters. Furthermore, prevalence and infection intensities of the swimbladder nematode Anguillicoloides crassus are highly increased in catadromous silver eels. Both, a reduced accumulation of fat reserves and intense A. crassus infestations are assumed to impair the successful reproduction of A. anguilla. These results highlight the importance of brackish water habitats for the production of high quality spawners and question the benefit of restocking measures into inland waters. In order to investigate the influence of water temperature and feeding behaviour on the element incorporation into A. anguilla otoliths, two experimental studies were conducted. Results showed that otolith element incorporation is influenced by water temperature, but detected differences between treatments were low to allow an in situ reconstruction of temperature history. In the food experiment no effect on otolith microchemistry was detected between feeding groups. Results indicate that neither temperature changes nor individual dietary behaviour impair the use of otolith Sr concentrations as a tracer of diadromy. Thus the reliability of such migration studies is fundamentally increased. It was further investigated whether multi-element otolith analysis can be used to discriminate Atlantic cod individuals according to their origin. Otolith multi-element concentrations from adult individuals caught at spawning grounds in the North Sea, the western Baltic Sea and the eastern Baltic Sea were analysed. Furthermore, the multi-element composition of the core region of juvenile cod otoliths from western and eastern Baltic areas was examined. Multivariate statistical analyses successfully discriminated between adults from different stocks as well as between western and eastern Baltic Sea juveniles. Significant differences between the eastern Baltic spawning grounds, however, were not detected. These results demonstrate the potential of otolith microchemistry analysis to investigate the structure and connectivity of G. morhua stocks in the Baltic Sea. In a further field study the migratory behaviour of thicklip grey mullet was examined for the first time on individuals caught in the Baltic Sea. By detecting C. labrosus otolith Sr concentrations, this study aimed to gain first insights into preferences and whereabouts of individuals in the Baltic Sea. Results confirmed a preference of brackish habitats for all analysed specimens and suggest a high plasticity of C. labrosus migratory behaviour. The results support the assumption that a considerable fraction of individuals entering the western Baltic Sea regularly migrate to the North Sea. The results presented in this thesis confirm the feasibility of otolith microchemistry analyses for the investigation of a broad range of questions on Baltic Sea fish. Knowledge about investigated species was expanded and opportunities for future studies were indicated. In dieser Arbeit wurden anhand mikrochemischer Otolithenanalysen Erkenntnisse über die individuelle Lebensweise und die Bestandsstruktur von drei Fischarten aus der Ostsee gewonnen – dem Europäischen Aal Anguilla anguilla, dem Atlantischen Kabeljau Gadus morhua und der Dicklippigen Meeräsche Chelon labrosus. Die hydrographischen Besonderheiten der Ostsee als weltgrößtes Brackwassersystem bieten vielversprechende Voraussetzungen für die Anwendung von Otolithen-Elementanalysen zur Untersuchung des individuellen Wanderverhaltens von Fischen und deren Bestandsstrukturen. Hier wurden sie genutzt, um managementrelevante Fragestellungen von Fischarten zu untersuchen, die sich hinsichtlich ihrer Biologie, Ökologie und Bestandsstruktur sehr unterscheiden. Es wurde untersucht, ob das kontinentale Wanderverhalten Europäischer Aale deren Gesundheit und Laicherqualität beeinflusst. Dazu wurden anhand der Otolithen-Strontiumverteilung charakteristische Wandermuster ermittelt. Die Ergebnisse zeigen, dass der Muskelfettgehalt von Blankaalen mit strikt katadromen Wanderverhalten signifikant geringer ist als der von Blankaalen, die niemals ins Süßwasser eingewandert sind. Darüber hinaus sind Prävalenz und Befallsintensität mit dem Schwimmblasen-Nematoden Anguillicoloides crassus bei katadromen Blankaalen stark erhöht. Sowohl eine verringerte Einlagerung von Fettreserven als auch der intensive Befall mit A. crassus stehen im Verdacht, den Reproduktionserfolg von A. anguilla zu vermindern. Die vorliegenden Ergebnisse heben die Bedeutung von Brackwasserhabitaten für die Produktion von gesunden Laichtieren hervor und stellen den Nutzen von Besatzmaßnahmen in Binnengewässer in Frage. Um den Einfluss von Wassertemperatur und Futterverhalten auf die Elementeinlagerung in A. anguilla-Otolithen zu prüfen, wurden zwei experimentelle Studien durchgeführt. Die Ergebnisse zeigen, dass die Einlagerung von Elementen in die Otolithen zwar von der Wassertemperatur beeinflusst wird. Die Unterschiede zwischen den Futtergruppen waren aber so gering, dass eine Rekonstruktion erlebter Temperaturänderungen in situ schwierig erscheint. Im Futterexperiment konnte kein Effekt auf die Elementeinlagerung detektiert werden Die Ergebnisse zeigen, dass weder Temperaturschwankungen noch unterschiedliches Futterverhalten die Verwendung von Sr zur Rekonstruktion diadromen Verhaltens einschränken. Damit wird die Aussagekraft solcher Migrationsstudien deutlich erhöht. Des Weiteren wurde untersucht, ob Otolithen-Multielementanalysen dazu geeignet sind, G. morhua-Individuen ihrer Herkunft zuzuordnen. Dazu wurde die Multielementzusammensetzung von Otolithen adulter Dorsch von Laichplätzen aus der Nordsee, der westlichen und der östlichen Ostsee untersucht. Des Weiteren wurde die Zusammensetzung der Kernbereiche von Otolithen juveniler Dorsche aus der westlichen und der östlichen Ostsee analysiert. Multivariate statistische Analysen konnten sowohl die adulten Bestände erfolgreich trennen, als auch die Juvenilen aus der westlichen und der östlichen Ostsee unterscheiden. Signifikante Unterschiede zwischen den drei östlichen Laichgebieten konnten aber nicht detektiert werden. Die Ergebnisse zeigen das Potential von Otolithen-Multielementanalysen zur Untersuchung der Struktur und Konnektivität von G. morhua-Beständen. In einer weiteren Feldstudie wurde das Wanderverhalten der Dicklippigen Meeräsche C. labrosus erstmals an Individuen aus der Ostsee untersucht. Ziel der Studie war es, mittels der Analyse von Sr-Konzentrationen in C. labrosus-Otolithen grundsätzliche Informationen über Aufenthaltsorte und Habitatspräferenzen der Ostsee-Meeräschen zu erlangen. Die Ergebnisse bestätigen die Präferenz von Brackwasserhabitaten und lassen eine hohe Plastizität des Wanderverhaltens vermuten. Sie stützen die Vermutung, dass ein erheblicher Teil der in die Ostsee einwanderenden Individuen regelmäßig in die Nordsee zurückkehrt. Die Ergebnisse dieser Arbeit bestätigen die gute Eignung mikrochemischer Otolithenanalysen zur Untersuchung unterschiedlichster Fragestellungen an Fischarten aus der Ostsee. Das Wissen über die untersuchten Arten wurde erweitert und neue Wege für zukünftige Studien wurden aufgezeigt.

International audience; Geochronological studies of samples from continuous crustal sections of fossil intra-oceanic arcs are paramount for determining the precise timing of major processes that took place during the building of an oceanic island-arc crust. In this study, laser ablation ICP-MS U-Pb zircon (and conventional Rb-Sr) analyses pinpoint the timing of major events responsible for crustal growth of the Kohistan paleo-island arc (Northern Pakistan). Inheritance in magmatic rocks is evidence for recycling of intra-arc material and indicates that the Kohistan arc may have formed as early as 135 +/- 4 Ma. One older inherited grain indicates that the arc developed on a young oceanic lithosphere whose remnants include a c. 175 Ma old component. An interesting consequence is that intra-oceanic arc magmas can yield inherited zircons, which can be much older than the arc system itself without requiring recycling back into the mantle by subduction processes. In the case of the Kohistan arc, ante-arc Neotethys oceanic lithosphere was tapped by arc magmas during their way upward into the arc crust. The oldest magmatic ages measured in this study fall in the range 101-102 Ma (100.9 +/- 0.6 and 102.1 +/- 0.4 Ma). This period corresponds to arc build-up and thickening of the arc crust. Leucogranitic melts dated at 89.9 +/- 0.4 Ma and 90.9 +/- 1.0 Ma are considered as produced by dehydration/melting reaction accompanying granulitisation of the thickened lower arc crust. A maximum age for this event is 97.7 +/- 0.7 Ma, the age of emplacement of a garnet meta-tonalite affected by granulite facies metamorphism. Magmatic activity was still ongoing during and after the granulitisation as testified by emplacement of a diorite and a gabbro dated at 89.1 +/- 0.6 and 88.2 +/- 0.9 Ma respectively. The upper part of the metaplutonic sequence contains diorite samples dated at 84.6 +/- 0.5 Ma and 84.3 +/- 0.5 Ma and as young as 81.1 +/- 0.7 Ma. During this period, and based on the present day outcropping sequences, the mean crustal growth rate varied from 32 to 65 km(3)/km/Ma (volume per unit width along the strike of the arc) which is comparable to the range for present day arcs of the Western Pacific region. The correspondence of crustal growth rates observed for present-day island arcs and the good preservation of the crustal section in the Kohistan arc, make this area an exceptional natural laboratory to study arc related processes and to check models of continental crust formation by arc accretion.

"Laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) is a rapidly growing technique that allows many different types of in-situ microanalyses to be performed in geological materials. One of the most used methodologies is U-Pb isotopic dating of accessory minerals such as zircon. These analyses can be performed at the scale of tenths of micrometers, in a rapid, cost-effective way and with very good precision and accuracy. It is critical, however, to perform the data reduction in a fast, transparent and customizable way that takes into account the specific analytical procedures employed in various laboratories and the outputs of different instruments. UPb.age is a freely available data reduction script, written and developed in R, a free statistical environment. The software can read, correct and reduce U-Pb isotopic data obtained by several LA-ICMPS instruments. Its main strengths are transparency, robustness, speed, and the ability to be readily customized and adapted to specific analytical procedures used in different laboratories."

This work demonstrates and further develops spatially resolved laboratory and synchrotron X-ray spectroscopic and imaging experiments to answer specific ecotoxicological questions on the model organism Daphnia magna. The first phase of this work consisted of developing appropriate sample preparation procedures for this organism in order to be able to perform X-ray analyses on Daphnia magna subjected to ecotoxicological experiments. In the second phase, X-ray set-ups at different laboratories and synchrotron facilities were optimized and characterized in order to be able to perform the X-ray spectral imaging experiments of interest on Daphnia magna. Finally, various data reduction strategies were employed to process the vast amount of spectral data for evaluation and interpretation.

La composition en éléments en trace incompatibles des assemblages métamorphiques des roches de HP-BT et des veines de l'Ile de Groix a été analysée par LA-ICPMS. Les éléments en trace sont majoritairement redistribués et recyclés entre les minéraux néoformés aux différentes étapes du cycle métamorphique, en fonction des réactions métamorphiques et des variations de stabilité des minéraux. Les roches conservent ainsi la signature géochimique de leur protolithe. La composition chimique et le rapport ?18O des veines progrades et rétrogrades révèlent que de fortes interactions fluide-roche favorisent la mobilisation et le transport des éléments en trace. En dépit de ces interactions fluide-roche, il est possible de caractériser la source et la composition des fluides, qui interagissent principalement avec les bordures des chenaux. En outre, la datation d'un orthogneiss découvert sur l'île a donné un âge de 480. 8 ± 4.8 Ma, contemporain du magmatisme felsique lié au rifting cambro-ordovicien.

Uranium is a naturally abundant element which has been used in several industries. Internal exposure could occur via three main pathways that are ingestion, inhalation and wounds. It has been recently shown that chronic ingestion of uranium in drinking water induces an important uranium accumulation in kidney with a perturbation of iron metabolism in this organ. Whereas uranium speciation is a key parameter to elucidate the chemical reactivity and the mobility of an element, it remains poorly documented in most of environmental and biological media. A few examples of uranium complexation with biomolecules have been published recently but most of them are in vitro studies whereas in vivo experiments remain poorly investigated. In order to better understand possible competition of uranium towards metals involved in the metal-protein binding, i.e. iron, copper, calcium, a study on uranium speciation was investigated by doing an in vivo screening of target proteins likely to bind it in kidneys of exposed rats. Rats were chronically exposed via contaminated drinking water at 40 mg L-1 and killed 9 months after the beginning of exposure. Kidneys were dissected out and protein extract was prepared. Then, separation of renal proteins by isoelectric focusing gel electrophoresis (IEF) and two-dimensional gel electrophoresis (2-DE) followed by LA-ICPMS analysis were performed. IEF-LA-ICP MS showed that uranium could specifically bind few proteins in kidney whereas 2-DE-LA-ICP MS could indicate that uranium is not covalently bound to proteins in this organ. The results suggested that even at moderate concentrations of exposure, uranium can be observed chelated with some renal proteins that is very encouraging to understand the entry, storage and elimination of this element in kidneys.

The monazite Th–Pb chronometer is widely used in a variety of geological contexts but may be affected by interaction with fluids. In the central part of the Rhodope Massif (Greece, Bulgaria), synfolial pegmatite veins were emplaced within two major synmetamorphic shear zones. In the Chepelare shear zone (CZS), which displays no evidence of post-metamorphic fluid flow, consistent monazite Th–Pb ages of ∼ 36 Ma are interpreted as dating vein emplacement. Higher in the metamorphic pile, zircon and monazite give U–Th–Pb ages of ∼ 42 Ma for vein emplacement. In the Nestos Shear Zone (NSZ) pegmatites show evidence of post-emplacement interaction with fluids during greenschist facies ductile deformation. Evidence for this includes the precipitation of calcite in microscale tension gashes within feldspar porphyroclasts, and the oxygen isotope disequilibrium between quartz and feldspar. Aqueous carbonic fluids deriving from carbonate lithologies in the footwall of the NSZ are identifiable in the pegmatites by the high δ18O value of quartz (up to 21.8‰) and the presence of calcium in calcite veinlets. In these samples, some of the monazite grains show large intragrain scattering of Th–Pb age spanning up to ∼ 12 Ma, with intergrain scattering reaching ∼ 16 Ma (from ∼ 39 to ∼ 55 Ma). Within individual grains, age domains correlate with chemical heterogeneities, and some show a characteristic Ca-excess. These chemical and isotopic alterations are interpreted to be caused by interaction with fluids derived from carbonate lithologies. Complementary U–Pb data on zircons from the NSZ pegmatites yield mostly Mesozoic ages related to an older metamorphic cycle, and an age of ∼ 48 Ma for one grain with typical magmatic zoning. The Th–Pb ages of 49.3 ± 1.6 to 54.9 ± 1.7 Ma probably relate to the emplacement of the pegmatites. The spread of younger Th–Pb ages (from 38.6 ± 1.1 to 46.2 ± 1.6 Ma) probably reflects the period of fluid circulation during progressive cooling to greenschist facies conditions, or variable perturbations of the monazite isotope system during fluid-assisted greenschist facies deformation. This is consistent with 39Ar–40Ar mica ages of ∼ 32 to 34 Ma, interpreted as a tighter constraint for the timing of the greenschist facies metamorphism. This study illustrates the capacity of monazite to record distinct events in a single rock and highlights the need for identifying the potential involvement of fluids in order to interpret monazite ages.

Devolatilization reactions and subsequent transfer of fluid from subducted oceanic crust into the overlying mantle wedge are important processes, which are responsible for the specific geochemical characteristics of subduction-related metamorphic rocks, as well as those of arc magmatism. To better understand the geochemical fingerprint induced by fluid mobilization during dehydration and rehydration processes related to subduction zone metamorphism, the trace element and rare earth element (REE) distribution patterns in HP-LT metamorphic assemblages in eclogite-, blueschist- and greenschist-facies rocks of the Ile de Groix were obtained by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) analysis. This study focuses on 10 massive basic rocks representing former hydrothermally altered mid-ocean ridge basalts (MORB), four banded basic rocks of volcano-sedimentary origin and one micaschist. The main hosts for incompatible trace elements are epidote (REE, Th, U, Pb, Sr), garnet [Y, heavy REE (HREE)], phengite (Cs, Rb, Ba, B), titanite [Ti, Nb, Ta, REE; HREE > LREE (light REE)], rutile (Ti, Nb, Ta) and apatite (REE, Sr). The trace element contents of omphacite, amphibole, albite and chlorite are low. The incompatible trace element contents of minerals are controlled by the stable metamorphic mineral assemblage and directly related to the appearance, disappearance and reappearance of minerals, especially epidote, garnet, titanite, rutile and phengite, during subduction zone metamorphism. Epidote is a key mineral in the trace element exchange process because of its large stability field, ranging from lower greenschist- to blueschist- and eclogite-facies conditions. Different generations of epidote are generally observed and related to the coexisting phases at different stages of the metamorphic cycle (e.g. lawsonite, garnet, titanite). Epidote thus controls most of the REE budget during the changing P-T conditions along the prograde and retrograde path. Phengite also plays an important role in determining the large ion lithophile element (LILE) budget, as it is stable to high P-T conditions. The breakdown of phengite causes the release of LILE during retrogression. A comparison of trace element abundances in whole-rocks and minerals shows that the HP-LT metamorphic rocks largely retain the geochemical characteristics of their basic, volcano-sedimentary and pelitic protoliths, including a hydrothermal alteration overprint before the subduction process. A large part of the incompatible trace elements remained trapped in the rocks and was recycled within the various metamorphic assemblages stable under changing metamorphic conditions during the subduction process, indicating that devolatilization reactions in massive basic rocks do not necessarily imply significant simultaneous trace element and REE release.

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T15:30:54Z No. of bitstreams: 9 Pre textuais.pdf: 233346 bytes, checksum: 9c32b6c5f4b55341d206ad8e77f2cfe3 (MD5) Cap 1a 3.pdf: 2541466 bytes, checksum: dcc391beb9094b33e11fef92e03f9e9e (MD5) Cap 4.pdf: 2375693 bytes, checksum: 85105fbdbeb66cf6edc6a9b65959cc63 (MD5) Cap 5.pdf: 2991197 bytes, checksum: db368fb6fa851ea40fb4efe2862701b0 (MD5) Cap 6.pdf: 2462637 bytes, checksum: ea675ad53f8651be37a67ab16ac0f186 (MD5) Cap 7A.pdf: 4014302 bytes, checksum: 35b43610f8e45719819a837d74b49b28 (MD5) Cap 7B.pdf: 4373237 bytes, checksum: 3faea761be93b496e6af979ed367f4dd (MD5) Cap 8 e referencias.pdf: 1028705 bytes, checksum: 59465196f8c22f1c5ce49cf84cb80d32 (MD5) Anexo V.pdf: 2313853 bytes, checksum: d4e72d7034bc9ca441def4f7ba206db5 (MD5) Made available in DSpace on 2021-01-05T15:30:54Z (GMT). No. of bitstreams: 9 Pre textuais.pdf: 233346 bytes, checksum: 9c32b6c5f4b55341d206ad8e77f2cfe3 (MD5) Cap 1a 3.pdf: 2541466 bytes, checksum: dcc391beb9094b33e11fef92e03f9e9e (MD5) Cap 4.pdf: 2375693 bytes, checksum: 85105fbdbeb66cf6edc6a9b65959cc63 (MD5) Cap 5.pdf: 2991197 bytes, checksum: db368fb6fa851ea40fb4efe2862701b0 (MD5) Cap 6.pdf: 2462637 bytes, checksum: ea675ad53f8651be37a67ab16ac0f186 (MD5) Cap 7A.pdf: 4014302 bytes, checksum: 35b43610f8e45719819a837d74b49b28 (MD5) Cap 7B.pdf: 4373237 bytes, checksum: 3faea761be93b496e6af979ed367f4dd (MD5) Cap 8 e referencias.pdf: 1028705 bytes, checksum: 59465196f8c22f1c5ce49cf84cb80d32 (MD5) Anexo V.pdf: 2313853 bytes, checksum: d4e72d7034bc9ca441def4f7ba206db5 (MD5) Previous issue date: 2008-09-09 Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro The crustal structure of the Ribeira Belt can be defined, in its central segment, by some tectono-estratigraphic terrains which are different, and limited by thrusts over São Francisco Craton and obliquous shear zones, result of successful docking events in the Brasiliano. In this context, the Paraíba do Sul Terrane is presented as a sinformal structure, covering the Occidental Terrane, a reworked margin of São Francisco Craton (Heilbron et al., 2004). Although the Ribeira mobile belt is the most studied in the West Gondwana, this study has contributed to the understanding of the constitution, origin and evolution of the units which compose the Paraíba do Sul Terrane, in this orogen. For that, systematic geochronological investigations were carried out, subsidized by lithogeochemical analysis, considering the regional character of the terrane being analyzed. This integrated study is necessary due to the few and spaciously restricted existing ages for the orthogneisses of the basement (Quirino Complex) and granitoids, and the absence of ages of provenance of its metasedimentary coverage (Paraiba do Sul Group). The litogeochemical data of 41 analyses (32 from Valladares et al., 2002) distinguish two calc-alkaline series for Quirino Complex: one of medium-K and tonalitic composition; other of high-K and granitic/granodioritic composition, related to a volcanic arc environment. Some possible cogenetic groups we identified, for each of these series (groups 1 to 8 for the high-K series, and 1 to 3 for the medium-K series), considering rates between incompatible elements varying below 1.5 times (Allégre & Minster, 1978) and other petrologic criteria, for the orientation of the geochronological investigation. The U-Pb geochronological analysis was performed by LA-ICPMS method, in zircons selected from ten samples, of which six were from orthogneisses from the Quirino Complex (four from the high-K series and two from the medium-K series), two from quartzites from Paraíba do Sul Group and two from neoproterozoic granitoids. All the analyses were produced by the author in the Radiogenic Isotope Facility of University of Alberta, Canada. The data obtained presented, for the Quirino Complex, palaeoproterozoic crystallization ages related to the Transamazonic Event, the high-K series being older (2308 ± 9.2 Ma a 2185 ± 8 Ma) that the medium-K series (2169 ± 3 Ma a 2136 ± 14 Ma). The integration of the geochronological data with the petrogenetic evaluation leads to the conclusion that four or five suites occur in the high-K serie. The medium-K series would be represented by one sole cogenetic suite, evolved by concomitant assimilation during fractioned crystallization, resulting, in part, from the melt of an archean crust during the same event which generated juvenile crust on the Palaeoproterozoic. The expressive quantity of inherited archean grains and TDM archean age (Valladares et al., 2002) support this hypothesis. The metasediments investigated are originated from the erosion of palaeoproterozoic rocks (with higher concentration between 1.9 Ga and 2.1 Ga), partly originated from the basement itself, together with subordinated contributions of archean sources. The maximum deposition age obtained at 1951 Ma (youngest zircon concordant), together with the oldest concordant age of the metamorphism of its basement (645 ± 13 Ma), defines the best estimate for the implementation of the Paraíba do Sul Basin, in some interval between the end of the Transamazonic Orogeny and the beginning of the Brasilian Orogeny. Three neoproterozoic metamorphic events were also identified based on registers of overgrowth grain, prismatic tips and lower intercepts of zircons of the basement and granitoid crystallization ages: one precocious, between 645-605 Ma, characterized in this study as pre-M1; and two subsequent, with intervals of 605-570 Ma and 540-520 Ma respectively correlated to Heilbron (1993) M1 and M2 events for the Ribeira Belt. Among the hypothesis for the metamorphic pre-M1 register, we suggest possible influence of the collision episodes, of chronorrelated age, south of the Brasilia Belt, or the existence of a fragment of continental crust positioned between the Rio Negro Arc (Oriental Terrane) and São Francisco Craton. In the second case, an accretion event of this crust fragment to the arc, from before the collision with the Craton, would result in the earlier metamorphism ages. Finally, the ID-TIMS age of 503 ± 2 Ma in titanite of the Quirino Complex (Valladares, 1996) would still be the youngest, reflecting the decrease of the metamorphic activity for this terrane. A estrutura crustal do Orógeno Ribeira pode ser definida, em seu segmento central, por alguns terrenos tectono-estratigráficos distintos entre si, e limitados por empurrões por sobre o Cráton de São Francisco e zonas de cisalhamento oblíquas, resultado de sucessivos eventos de colagem no Brasiliano. Neste contexto, o Terreno Paraíba do Sul se apresenta como uma estrutura sinformal, recobrindo o Terreno Ocidental, margem retrabalhada do Cráton de São Francisco (Heilbron et al., 2004). Ainda que o Orógeno Ribeira seja o mais estudado do Gondwana Oeste, esta tese contribui para o entendimento da constituição, origem e evolução das unidades que compõem o Terreno Paraíba do Sul, neste orógeno. Para tanto foram realizadas investigações geocronológicas sistemáticas subsidiadas por análises litogeoquímicas, tendo em vista o caráter regional do terreno estudado. Este estudo integrado se faz necessário em virtude da poucas e espacialmente restritas idades existentes para os ortognaisses do embasamento (Complexo Quirino) e granitóides, e à ausência de idades de proveniência de sua cobertura metassedimentar (Grupo Paraíba do Sul). Os dados litogeoquímicos de quarenta e uma análises (trinta e duas de Valladares et al., 2002) discriminam duas séries cálcio-alcalinas para o Complexo Quirino: uma de médio-K e composição tonalítica; e outra de alto-K e composição granítica/granodiorítica, relacionadas a ambiente de arco vulcânico. Foram ainda identificados alguns possíveis grupos cogenéticos, para cada uma destas séries (grupos 1 a 8 para a série de alto-K, e 1 a 3 para a série de médio-K), considerando razões entre elementos incompatíveis com variações inferiores a 1,5 vezes (Allégre & Minster, 1978) e outros critérios petrológicos, para orientação da investigação geocronológica. A análise geocronológica U-Pb foi realizada pelo método LA-ICPMS, em zircões selecionados de dez amostras, sendo seis de ortognaisses do Complexo Quirino (quatro da série de alto-K e duas da série de médio-K), duas de quartzitos do Grupo Paraíba do Sul e duas de granitóides neoproterozóicos. Todas as análises foram produzidas pelo autor no Radiogenic Isotope Facility of University of Alberta, Canadá. Os dados obtidos apresentaram, para o Complexo Quirino, idades de cristalização paleoproterozóica relacionadas ao Evento Transamazônico, sendo a série de alto-K mais antiga (2308 ± 9,2 Ma a 2185 ± 8 Ma) do que a série de médio-K (2169 ± 3 Ma a 2136 ± 14 Ma). A integração dos dados geocronológicos obtidos, com as avaliações petrogenéticas, possibilita a interpretação de que quatro ou cinco suítes ocorram na série de alto-K. A série de médio-K seria representada por uma única suíte cogenética, evoluída por assimilação concomitante à cristalização fracionada, consequente de fusão de crosta arqueana pré-existente durante o mesmo evento que gerou crosta juvenil. A expressiva quantidade de grãos herdados e idade TDM (Valladares et al., 2002) corroboram com esta hipótese. Os metassedimentos investigados são provenientes da erosão de rochas paleoproterozóicas (com maior concentração entre 1,9 Ga e 2,1 Ga), em parte oriundas do próprio embasamento, juntamente com contribuições subordinadas de fontes arqueanas. A idade de deposição máxima obtida a 1951 Ma (zircão concordante mais jovem), juntamente com a idade concordante mais antiga de metamorfismo do seu embasamento (645 ± 13 Ma), define a melhor estimativa para a implantação da Bacia Paraíba do Sul em algum intervalo entre o final da Orogenia Transamazônica e o início da Orogenia Brasiliana. Três eventos metamórficos neoproterozóicos também foram identificados com base em registros de bordos de grãos, pontas de prismas e interceptos inferiores de zircões do embasamento e idades de cristalização de granitóides: um precoce, entre 645-605 Ma caracterizado nesta tese como pré-M1; e outros dois subseqüentes, com intervalos de 605-570 Ma e 540-520 Ma correlacionáveis respectivamente aos eventos M1 e M2 de Heilbron (1993) para o Orógeno Ribeira. Dentre as hipóteses para o registro metamórfico pré-M1, é sugerida uma possível influência dos episódios colisionais, de idade cronocorrelata, ao sul do Orógeno Brasília, ou a existência de um fragmento de crosta continental posicionada entre o Arco Rio Negro (Terreno Oriental) e o Cráton de São Francisco. No segundo caso, um evento de acresção deste fragmento de crosta ao arco, anterior à colisão com o Cráton, resultaria nas idades de metamorfismo mais precoce. Por fim, a idade ID-TIMS de 503 ± 2 Ma em titanita do Complexo Quirino (Valladares, 1996) continuaria sendo a mais nova, refletindo a diminuição da atividade metamórfica para este terreno.

LA-ICPMS U–Pb data from metamorphic monazite in upper amphibolite and granulite-grade metasedimentary rocks indicate that the Nawa Domain of the northern Gawler Craton in southern Australia underwent multiple high-grade metamorphic events in the Late Paleoproterozoic and Early Mesoproterozoic. Five of the six samples investigated here record metamorphic monazite growth during the period 1730–1690 Ma, coincident with the Kimban Orogeny, which shaped the crustal architecture of the southeastern Gawler Craton. Combined with existing detrital zircon U–Pb data, the metamorphic monazite ages constrain deposition of the northern Gawler metasedimentary protoliths to the interval ca 1750–1720 Ma. The new age data highlight the craton-wide nature of the 1730–1690 Ma Kimban Orogeny in the Gawler Craton. In the Mabel Creek Ridge region of the Nawa Domain, rocks metamorphosed during the Kimban Orogeny were reworked during the Kararan Orogeny (1570–1555 Ma). The obtained Kararan Orogeny monazite ages are within uncerta...

Variation in the chemical composition of fish otoliths has been used in recent years to address a range of ecological questions, including levels of stock mixing, variation in habitat use, and rates of larval exchange. While some of these questions have been answered with varying success, the degree to which discrete populations are connected via larval exchange remains unknown. To identify larval sources using natural variation in otolith chemistry, we must distinguish and measure the chemical composition of the otolith core, the portion of the otolith formed at the spawning site. Using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS), we found that the core regions of otoliths from 6 different species of fishes were highly enriched in manganese (Mn), and elevated in magnesium (Mg) and barium (Ba), relative to adjacent regions of the otolith. These patterns were consistent for species drawn from different taxonomic groups, which inhabit temperate and tropical regions, are found in marine and freshwater, and utilize a variety of spawning modes. Variation among species in Mn concentration in the core also corresponds to maternal investment, measured by egg size. These data suggest that core enrichment may be a general characteristic of otoliths, and that the chemical composition of the otolith core is fundamentally different from other regions of the otolith. The localized elemental enrichment of the core underscores the importance of methods that analyze the core region in small, discrete samples if otolith chemistry is used to address questions of larval exchange among populations.

Mineral exploration and sustainable developmentMineral exploration and sustainable development : proceedings of the Seventh Biennial SGA Meeting, Athens, Greece, 24-28 August 2003, ISBN:90-77017-77-1

This paper deals with the first results of chemical elementary analyse of early cretaceous flint from South Eastern France. These flints have been exchanged, principally during the Neolithic, between the Alps and the Pyrenean. The analyses concern geological samples, from a primary or secondary position, and archaeological samples as well. The latter are coming from excavations concerning significant archaeological entities. Raw and archaeological materials, attributed to several geological deposit (late cretaceous, tertiary) have been sampled to contrast the results. These analyses specially use LA-ICPMS, a non-destructive method whose results are compared with destructive ones (liquid ICP MS, ARNC). Several markers of provenance have been identified. These traces let us distinguish major geological deposits, and, let us exceptionally establish differences between early cretaceous flints. After this first approach, it will be necessary to increase the number of analysed samples and use a multidimensional statistical treatment in order to specify the differences and variability observed., Cet article expose les premiers résultats des analyses chimiques élémentaires mises en œuvre pour tenter de caractériser les silex crétacés (bédouliens) de Haute-Provence qui circulent, notamment au Néolithique, entre les Alpes et les Pyrénées. Les analyses concernent des échantillons géologiques prélevés en place, en position primaire ou plus rarement secondaire, ainsi que des échantillons archéologiques issus de fouilles concernant des ensembles culturels significatifs. Des matériaux géologiques et archéologiques, attribués à d'autres formations (turonien, éocène, oligocène), ont été introduits dans le corpus analysé pour contraster les résultats. Ces analyses mettent plus particulièrement en œuvre la méthode LA-ICPMS, non destructive dont les résultats sont comparables à des méthodes destructives (ICP MS en mode liquide, ARNC). Quelques marqueurs de provenance ont été ainsi mis en évidence. Ces éléments présents à l'état de trace permettent d'opérer des distinctions entre les étages et, plus exceptionnellement au sein du Bédoulien. Après cette première approche, il s'avérera nécessaire d'augmenter le nombre d'analyses et de mettre en œuvre des traitements statistiques multidimensionnels de manière à préciser les différences et les variabilités observées., Blet-Lemarquand Maryse, Binder Didier, Gratuze Bernard. Essais de caractérisation des silex bédouliens provençaux par analyse chimique élémentaire.. In: Revue d'Archéométrie, n°24, 2000. pp. 149-167.