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Colli Albani is a quiescent caldera complex located within the Roman Magmatic Province (RMP), Italy. The recent Via dei Laghi phreatomagmatic eruptions led to the formation of nested maars. Albano Maar is the largest and has erupted seven times between ca 69–33ka. The highly explosive nature of the Albano Maar eruptions is at odds with the predominant relatively mafic (SiO 2 =48–52wt.%) foiditic...
The Chinese Tianshan occupies the southernmost part of the Central Asian Orogenic Belt (CAOB). High-grade metamorphic rocks are widely distributed in its central uplift zones, composing the crustal basement of the Central Tianshan Block of the Chinese Tianshan. However, the origin of the crustal basement and whether the high-grade metamorphism was associated with the Paleozoic orogeny are still unresolved...
Oscillatory zoned garnets are able to record numerous geological processes including variations of physicochemical conditions and hydrothermal fluid evolution. In this contribution, we present the mineralogy, petrography, and systematic major, trace and rare earth element (REE) concentrations of zoned garnets from the Xieertala Fe–Zn skarn deposit. The in situ analytical results of oscillatory zoned...
Subduction processes on early earth are controversial, with some suggestions that tectonics did not operate until the earth cooled to a sufficient point around the Archean–Proterozoic boundary. One way of addressing this issue is to examine well-preserved successions of Archean supracrustal rocks. Here we discuss petrography, whole-rock chemical and isotopic data combined with zircon Hf isotopes from...
AFC3D is an original graphical free software developed in the framework of the R scientific environment and dedicated to the modelling of assimilation and fractional crystallization without (AFC) and with (AFC-r) recharge, facilitating the search for the solutions of the equations originally proposed by DePaolo (1981, 1985) and first solved in a graphical way by Aitcheson and Forrest (1994). The software...
Large-scale Cu–Au mineralization is associated with the Late Mesozoic granitoids in the Jiurui district of the Middle–Lower Yangtze Mineralization Belt in Eastern China. To constrain the petrogenesis of these granitoids and coeval mafic rocks, a detailed geochemical and Sr–Nd–Pb–Hf isotopic study was performed. The Jiurui granitoids are made up primarily of granodiorite porphyry and quartz diorite...
The lithospheric, and shallow asthenospheric, mantle in Southern Victoria Land are known to record anomalously high heat flow but the cause remains imperfectly understood. To address this issue plagioclase peridotite xenoliths have been collected from Cenozoic alkalic igneous rocks at three localities along a 150km transect across the western shoulder of the West Antarctic rift system in Southern...
We investigate the texture and chemical zoning of phenocrysts of six basic lavas (five basalts and one basaltic andesite) from the Marsili volcano, the superinflated spreading ridge of the Marsili back-arc basin (Southern Tyrrhenian). The samples, dredged from different portions of the volcano, were selected in order to represent the two distinct mafic magmas that sourced its plumbing system. Four...
Studies on zircon ages, petrology, major and trace element geochemistry, and Sr–Nd–Hf–Pb isotopic geochemistry of intermediate volcanic rocks from the Southern Yidun arc, Sanjiang-Tethyan Orogenic Belt, SW China have been undertaken in this paper. They are used to discuss the petrogenesis of these rocks and to constrain the tectonic setting and evolution of the Yidun arc. These intermediate volcanic...
Silicon (Si) is the defining element of silicate reservoirs yet, despite its dominance in major Earth processes, there is still no clear understanding of how much is hosted in Earth's core, how the enriched continental crust forms or even if the crust is isotopically different from the mantle because of a long history of weathering, erosion and subduction. With the advent of multiple collector inductively...
Crustal anatectites are frequently observed along ocean–continent active margins, although their origins are disputed with interpretations varying between rift-related and collisional. We report geochemical, isotopic and geochronological data that define an ~1500km long belt of S-type meta-granites along the Andes of Colombia and Ecuador, which formed during 275–223Ma. These are accompanied by amphibolitized...
The Chugach Metamorphic Complex (CMC) is a large high-grade metamorphic complex that developed in the Eocene within the Chugach accretionary complex along the margin of Alaska where subduction is still ongoing. The CMC has a conspicuous asymmetric structure with a migmatitic zone flanked in the north and west by amphibolite facies schists and in the south by a metabasite belt. To the north and south,...
In the early Permian large volumes of volcanic rocks developed in the Eastern Tianshan of the southern Altaids. The Shaerhu alkaline complex, which occurs along a NW-trending transcurrent fault in the Dananhu arc, is composed of alkaline gabbro intrusions, granites and rhyolites; the gabbros and rhyolites have similar zircon crystallization ages of 286.5±2.1Ma and 286.7±2.1Ma, respectively. The granitic...
The Beja Layered Gabbroic Sequence (LGS) intruded the SW border of the Ossa Morena Zone at ca. 350Ma during the early stages of the Variscan oblique continental collision in Iberia. It represents an exceptional case-study for the petrogenesis and metallogenesis of the rare class of synorogenic layered intrusions.LGS oxidised parental magmas (+1.7±0.5 ΔFMQ) evolved to relatively reduced ferro-basaltic...
In situ Zircon U–Pb ages and Hf-isotopes, whole-rock major- and trace elements, and Sr–Nd isotopic compositions of the Liudusi and Taiboding intrusions in the Jiaodong Peninsula (eastern China) are presented to trace their petrogenesis and relationships to lithosphere evolution. The Liudusi complex, which consists of biotite-bearing gabbro and quartz monzonite, formed at ca 115Ma. The rocks show shoshonitic...
A more than 12km wide sheeted tonalite complex in western Sierra de Famatina, NW Argentina, was emplaced at middle crust levels (ca. 5kbar), coeval with regional metamorphism during an early phase of the Ordovician Famatinian orogeny (ca. 480Ma). Advective heat from the tonalite complex caused a rise in the host regional temperatures (≤700°C) by a maximum of ca. 100°C, developing an aureole (~3km...
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