Search results for "Conti"
showing 10 items of 3486 documents
Synthesis of potentially anti-inflammatory IPL576,092-contignasterol and IPL576,092-manoalide hybrids
2004
The synthesis of two potentially anti-inflammatory steroidal hybrid compounds has been accomplished through a 16- and 17-step sequence, respectively, starting from commercially available androst-5-en-3β-ol-17-one. The synthetic strategies are based both on stereoselective side chains elaboration and high yielding functional group transformations.
Structural highs formation and their relationship to sedimentary basins in the north Sicily continental margin (southern Tyrrhenian Sea): implication…
2005
Two high-penetration seismic profiles across the continental margin of north Sicily (southern Tyrrhenian Sea) have been interpreted to construct a crustal section across the margin and to provide a three-dimensional perspective on the upper crustal setting of the Solunto High and its structural relationships with the adjacent Cefalù Basin. Crystalline rocks of the Kabilian-Calabrian Units (KCU) are recognized in the Solunto High region and farther to the north. The KCU body is tectonically superimposed onto sedimentary rocks pertaining to the Sicilian-Maghrebian Units (SMU) and the Solunto High corresponds to the thrust sheet culmination. Its occurrence in the Solunto High demonstrates that…
Generation of Earth's early continents from a relatively cool Archean mantle
2019
This research has been supported by DFG grant, SPP 1833 Building a Habitable Earth and MAGMA Consolidator Grant (ERC project #71143). Several lines of evidence suggest that the Archean (4.0 2.5 Ga) mantle was hotter than today's potential temperature (TP) of 1350 ° C. However, the magnitude of such difference is poorly constrained, with TP estimation spanning from 1500 ° C to 1600 ° C during the Meso‐Archean (3.2‐2.8 Ga). Such differences have major implications for the interpreted mechanisms of continental crust generation on the early Earth, as their efficacy is highly sensitive to the TP. Here, we integrate petrological modeling with thermomechanical simulations to understand the dynami…
Active geodynamics of the central Mediterranean Sea: Tensional tectonic evidences in western Sicily from mantle-derived helium
2005
[1] We report results on the measured high 3He/4He isotope ratio in western Sicily, interpreted together with the heat data. The study of this sector of the Europe-Africa interaction is crucial to a better understanding of the tectonics and the geodynamical evolution of the central Mediterranean area. The estimated mantle-derived helium fluxes in the investigated areas are up to 2–3 orders of magnitude greater than those of a stable continental area. The highest flux, found in the southernmost area near the Sicily Channel, where recent eruptions of the Ferdinandea Island occurred 20 miles out to sea off Sciacca, has been associated with a clear excess of heat flow. Our results indicate that…
Post-collisional adakite-like magmatism in the Ağvanis Massif and implications for the evolution of the Eocene magmatism in the Eastern Pontides (NE …
2011
In the Anatolia, the Caucasus and northwest Iran, the Eocene epoch is characterized by widespread basic to acidic magmatism, whose temporal and spatial evolutions and origin are poorly understood. In this paper, we provide geochronological and geochemical data on a suite of Early Eocene intrusions from northeast Turkey and discuss their origin within a regional tectonic framework. Post to late-collisional, moderate to small bodies of quartz diorite and leucogranodiorite as well as later dacite porphyries intrude Permo-Triassic low-grade metamorphic rocks in the southern part of the Eastern Pontides very close to the Neo-Tethyan Izmir-Ankara-Erzincan suture. In places, the intrusives display…
Characterization of an early metamorphic stage through inclusions in zircon of a diamondiferous quartzofeldspathic rock from the Erzgebirge, Germany
2003
About 1000 zircon grains from a diamondiferous quartzofeldspathic rock of the Saxonian Erzgebirge were investigated for inclusions using optical microscopy and confocal laser-Raman spectroscopy. Cathodoluminescence imagery was applied to characterize the growth zone of zircon where the inclusions occurred. The most abundant inclusion minerals are microdiamonds. Coesite was not detected. However, garnet and jadeite occur as rare inclusions in zircon cores where diamonds are lacking. Jadeite was detected for the first time in quartzofeldspathic rocks from the crystalline complex of the Erzgebirge. The compositions of the pristine garnets in the zircons are similar to those of core areas of mi…
Internal Differentiation of the Archean Continental Crust: Fluid-Controlled Partial Melting of Granulites and TTG-Amphibolite Associations in Central…
2009
Fault bound blocks of granulite and enderbite occur within upper amphibolite-facies migmatitic tonalitic-trondhjemitic-granodioritic (TTG) gneisses of the Iisalmi block of Central Finland. These units record reworking and partial melting of different levels of the Archean crust during a major tectonothermal event at 2·6-2·7 Ga. Anhydrous mineral assemblages and tonalitic melts in the granulites formed as a result of hydrous phase breakdown melting reactions involving amphibole at peak metamorphic conditions of 8-11 kbar and 750-900°C. A nominally fluid-absent melting regime in the granulites is supported by the presence of carbonic fluid inclusions. The geochemical signature of light rare e…
Precambrian crustal evolution and continental drift
1981
One of the major questions of Precambrian research is whether present-day plate tectonic models can be applied to the evolution of the ancient continental crust or whether the tectonic style suggests a unidirectional and therefore non-uniformitarian development in response to gradual changes in the global thermal regime through time.
Costruzioni discorsive sull’Europa e sui rapporti tra continenti nell’antichità greca
2019
L’articolo studia le retoriche cui sono state sottoposte le identità rappresentate dai continenti. Viene mostrato così che la mitica parentela originaria ha dato luogo ora ad un legame di solidarietà tra i popoli che occupano l’una o l’altra zona geografica, ora ad una giustificazione delle pretese imperialistiche di un popolo su un altro. Si mostra altresì che i confini tra i continenti vengono presentati, a seconda del punto di vista difensivo o aggressivo da cui se ne parla, ora come segni di una ‘architettura’ naturale di cui si pretende il rispetto, ora come ostacoli da superare in nome dell’amore della conoscenza che vuole esplorare l’ignoto o dell’addomesticamento di ciò che è selvag…
Διαλεκτικές κατασκευές για την Ευρώπη και για τις σχέσεις ανάμεσα σε ηπείρους στην ελληνική αρχαιότητα
2020
L’articolo studia le retoriche cui sono state sottoposte le identità rappresentate dai continenti. Viene mostrato così che la mitica parentela originaria ha dato luogo ora ad un legame di solidarietà tra i popoli che occupano l’una o l’altra zona geografica, ora ad una giustificazione delle pretese imperialistiche di un popolo su un altro. Si mostra altresì che i confini tra i continenti vengono presentati, a seconda del punto di vista difensivo o aggressivo da cui se ne parla, ora come segni di una ‘architettura’ naturale di cui si pretende il rispetto, ora come ostacoli da superare in nome dell’amore della conoscenza che vuole esplorare l’ignoto o dell’addomesticamento di ciò che è selvag…