676 research outputs found
Lettera di Alessandra
No full textUn ritratto critico dell'opera di Alessandra Carnaroli, autrice fra le più apprezzate delle ultime generazioni della poesia di ricerca. La sezione a lei dedicata, nel numero della rivista, contiene inoltre saggi di Cecilia Bello Minciacchi, Andrea Cortellessa, e Ivan Schiavone; e vari inediti dell'autrice. Il saggio è pubblicato con lo pseudonimo di Tommaso Ottonieri.A critical portrait of the work of Alessandra Carnaroli, author of the most appreciated in the latest generations of italian research poetry. Published under the pseudonym Tommaso Ottonieri
Multiphase inclusions in peritectic garnet from granulites of the Athabasca granulite terrane (Canada): Evidence of carbon recycling during Neoarchean crustal melting
No full textIn the last decade, the study of fluid and melt inclusions in partially melted rocks has become a key tool to acquire unprecedented information about crustal anatectic processes. In this study we report the results of the microstructural and microchemical investigation on multiphase inclusions trapped within peritectic garnet of a Neoarchean felsic granulite from the Upper Deck domain of the Athabasca granulite terrane, Canada. Inclusions have been studied by SEM-EDS, FIB-SEM serial sectioning and Raman microspectroscopy, and classified in terms of size and hosted phases. Type I multiphase inclusions are small (≤15 μm), primary in origin, and do not show evidence of decrepitation. Their multiphase assemblage is made of ferroan magnesite, quartz and graphite in association with minor amounts of corundum, pyrophyllite and Zn-spinel. Calcite, dolomite and zinc-bearing sulphide may also be present. The coexistence of quartz and corundum in these inclusions is interpreted as the product of metastable growth within pores of extremely small size. The fluid phase of Type I inclusions, always present in amounts >40 vol%, is CO2-rich (96.5 mol%) with traces of N2 (3.3 mol%) and CH4 (0.2 mol%). These carbon-rich Type I inclusions coexist in the same cluster with primary melt inclusions (nanogranitoids; Type II). These are large (up to 50 μm) and composed of K-feldspar, quartz and plagioclase with minor amounts of graphite, biotite and aluminosilicate. Because nanogranitoids are droplets of anatectic silicate melt formed and trapped during incongruent melting of crustal rocks, the coexistence of Type I multiphase inclusions proves the presence of a carbon-rich fluid during the Neoarchean anatexis (800–950 °C, 0.6–1.4 GPa) of this portion of continental crust, in a likely situation of melt/fluid immiscibility. According to phase equilibria modelling, the uncommon multiphase assemblage within Type I inclusions is here interpreted as the result of a post-entrapment carbonation reaction between an original CO2-bearing fluid and the garnet host during rock cooling from UHT conditions
Editorial: Dysmetabolism, obesity, and inflammation: Three prominent actors in the drama of major neuropsychiatric disorders
No full textEvidenze di deformazione in facies granulitica lungo la linea milonitica di Amaroni: applicazione EBSD al quarzo. Evidence of deformation in granulite facies on Amaroni mylonitic line: EBSD quartz application
No full textIn this work we have studied a sample from Amaroni shear zone, in Calabrian Serre Massif. In this zone is placed an important alpine thrust such as Curigna-Girifalco Lines that separates the deepest high grades metamorphic basement from upper lower grade metamorphic domains. Therefore, in this place there is an outcropping portion of hercynian continental crust exumated by tertiary tectonic.
The sample comes from migmatitic paragneiss dated about 300 My. This age is obtained by Zircon dating that identifies a metamorphic peak. This is related to an important magmatic activity, with an emplacement of granitoids magmas in the intermediate crust.
Later, this deep portion was affected and involved in alpine and appenninic orogeny that produced a nappes stacking from different geologic provenience.
The analysis has been made with SEM, using crystallographic techniques like EBSD.
This study is finalized to verify the presence of hypothetical deformation in granulitic facies, in the high temperature condition
Studio di inclusioni policristalline in granati di granuliti dell'Athabasca Granulite Terrane (Canada)
No full textFluid inclusions in minerals represent an important tool to investigate the processes involved in the petrogenesis of rocks, including the fluid-rock-melt interactions during anataxis. In this work a detailed microstructural and microchemical study has been performed on polycrystalline inclusions trapped in peritectic garnets of felsic granulite gneisses from the Upper Deck domain, Athabasca Granulite Terrane (Canada). Inclusions have been characterized by SEM-EDS and FIB-SEM techniques, and by Raman spectroscopy. These inclusions are very small (≤ 10 μm), they are primary and do not show evidences of decrepitation. FIB-SEM analyses permitted to recognise the main crystalline phases and their distribution. Their polycrystalline assemblage is always made of ferroan magnesite, quartz and graphite, in association with minor amounts of corundum and Zn-spinel. Calcite and dolomite may be present, and pyrophyllite was found only in one inclusion. Quartz and corundum coexistence has been interpreted as the product of metastability. Raman spectroscopy revealed the presence of CO2, with traces of CH4 and N2. A good negative correlation between the CO2 density and the total amount of coexisting solid phases has been observed. The main minerals occur in a relatively constant amount in the investigated inclusions, suggesting the entrapment of a compositionally homogeneous fluid characterized by a high-carbon content. These tiny carbon-rich inclusions coexist in the same cluster with nanogranite inclusions. Because nanogranites are interpreted to be droplet of anatectic melt formed and trapped during incongruent melting of crustal rocks, the investigated polycrystalline inclusions prove the presence of a carbon-rich fluid during melting of these rocks, possibly in a situation of melt/melt or melt/fluid immiscibility. Additional melting experiments are needed to better constrain the nature of former fluid
Nanoscale Investigation of Metamorphic Processes
No full textThis doctoral thesis presents micro to nanoscale investigations of metamorphic processes taking place within Earth’s lower crust. Atom probe tomography, together with a wide range of cutting-edge techniques, has been applied to well-preserved rocks that have been affected by interactions with fluids in different geological contexts and under different extent of deformation. The integrated outcome of this research provides unprecedented insights into the complex interplay between rock, fluids, and deformation
Studio di inclusioni policristalline in granati di granuliti dell'Athabasca Granulite Terrane (Canada)
No full textFluid inclusions in minerals represent an important tool to investigate the processes involved in the petrogenesis of rocks, including the fluid-rock-melt interactions during anataxis. In this work a detailed microstructural and microchemical study has been performed on polycrystalline inclusions trapped in peritectic garnets of felsic granulite gneisses from the Upper Deck domain, Athabasca Granulite Terrane (Canada). Inclusions have been characterized by SEM-EDS and FIB-SEM techniques, and by Raman spectroscopy. These inclusions are very small (≤ 10 μm), they are primary and do not show evidences of decrepitation. FIB-SEM analyses permitted to recognise the main crystalline phases and their distribution. Their polycrystalline assemblage is always made of ferroan magnesite, quartz and graphite, in association with minor amounts of corundum and Zn-spinel. Calcite and dolomite may be present, and pyrophyllite was found only in one inclusion. Quartz and corundum coexistence has been interpreted as the product of metastability. Raman spectroscopy revealed the presence of CO2, with traces of CH4 and N2. A good negative correlation between the CO2 density and the total amount of coexisting solid phases has been observed. The main minerals occur in a relatively constant amount in the investigated inclusions, suggesting the entrapment of a compositionally homogeneous fluid characterized by a high-carbon content. These tiny carbon-rich inclusions coexist in the same cluster with nanogranite inclusions. Because nanogranites are interpreted to be droplet of anatectic melt formed and trapped during incongruent melting of crustal rocks, the investigated polycrystalline inclusions prove the presence of a carbon-rich fluid during melting of these rocks, possibly in a situation of melt/melt or melt/fluid immiscibility. Additional melting experiments are needed to better constrain the nature of former fluid.ope
Evidenze di deformazione in facies granulitica lungo la linea milonitica di Amaroni: applicazione EBSD al quarzo. Evidence of deformation in granulite facies on Amaroni mylonitic line: EBSD quartz application
No full textIn this work we have studied a sample from Amaroni shear zone, in Calabrian Serre Massif. In this zone is placed an important alpine thrust such as Curigna-Girifalco Lines that separates the deepest high grades metamorphic basement from upper lower grade metamorphic domains. Therefore, in this place there is an outcropping portion of hercynian continental crust exumated by tertiary tectonic.
The sample comes from migmatitic paragneiss dated about 300 My. This age is obtained by Zircon dating that identifies a metamorphic peak. This is related to an important magmatic activity, with an emplacement of granitoids magmas in the intermediate crust.
Later, this deep portion was affected and involved in alpine and appenninic orogeny that produced a nappes stacking from different geologic provenience.
The analysis has been made with SEM, using crystallographic techniques like EBSD.
This study is finalized to verify the presence of hypothetical deformation in granulitic facies, in the high temperature condition.ope
Una facezia di Poggio nell'«Epirota» di Tommaso de Mezzo
No full textPrinted in 1483, Tommaso de Mezzo’s «Epirota» belongs to the second time of the
latin humanistic comedy of the Quattrocento, characterized by a strictly imitation of
Plaute (and also of Terence), more strong than in the texts of the first half of the century.
The first section of this paper presents Tommaso de Mezzo’s life and works, and plot,
types and subjects of «Epirota». The second part of the article offers the analysis of some
scenes of the comedy, in which the author clearly employs one of Bracciolini’s «Facetiae»
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