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The Zabili granitic pluton (SW Chad) exposed in the Mayo Kebbi massif is dominated by a coarse-grained hornblende biotite granite grading into a fine-grained biotite granite along its southern margin. Petrologic (micrographic intergrowth of quartz and alkali feldspars, granophyric microstructures, the presence of fluorite and bastnaesite as accessory minerals) and geochemical data (high silica, alkalis...
Major and trace element, whole rock Sr‐, Nd‐and Hf‐isotopes and zircon U–Pb age and Hf–O isotope data have been determined for mafic to felsic intrusive rocks from the Late Triassic Mayihe (MYH), Longtou–Chaxinzi–Xiaoweishahe (LCX) and Nankouqian–Xidadingzi (NX) intrusions in the northern Liaodong Peninsula, NE China, in order to investigate their sources and petrogenesis related to decrationization...
Phanerozoic granitoids are widespread in the Korean Peninsula and form a part of the East Asian Cordilleran-type granitoid belt extending from southeastern China to Far East Russia. Here we present SHRIMP zircon U–Pb ages and geochemical and Nd isotopic compositions of Late Paleozoic to Early Jurassic granitoid plutons in the northern Gyeongsang basin, southeastern Korea; namely the Jangsari, Yeongdeok,...
The Neoproterozoic post-collisional period in southern Brazil (650–580Ma) is characterized by substantial volumes of magma emplaced along the active shear zones that compose the Southern Brazilian Shear Belt. The early-phase syntectonic magmatism (630–610Ma) is represented by the porphyritic, high-K, metaluminous to peraluminous Quatro Ilhas Granitoids and the younger heterogranular, slightly peraluminous...
The telluric planets and the asteroid belt display the same internal structure with a metallic inner core and a silicate outer shell. Experimental data and petrological evidence in silicate systems show that granite can be produced by extreme igneous differentiation through various types of igneous processes.On Moon, 4.4–3.9Ga granite clasts display dry mineral assemblages. They correspond to at least...
Located at the internal border of the Grand-Saint-Bernard Zone, the diorite and its aureole lie on top of intensively studied Alpine eclogitic units but this pluton, poorly studied yet, has kept locally almost undeformed. The pluton intruded, at ~360Ma, country-rocks mostly composed of dark shales with Na 2 O>K 2 O and minor mafic intercalations of tholeiitic basalt affinity. This...
A multiphase granitic complex (G1–G6) in the Carrazeda de Ansiães area, Central Iberian Zone, was emplaced during syn-kinematic stages of the Variscan orogeny, between 329.9±0.8Ma and 318.9±1.9Ma, as determined by ID-TIMS U–Pb on zircon and monazite. The complex intruded the metasedimentary Douro Group in a NW trending antiform formed during the D 1 and D 3 deformation phases, but...
Late Carboniferous U–Pb ages have been measured on igneous zircon from late- and post-D 3 Sn-bearing two-mica granites from the Gouveia area in the Central Iberian Zone. Inherited zircon from these granites is mainly of Neoproterozoic age, a small amount is Paleoproterozoic and Cambrian, and none is Mesoproterozoic. The most likely source of the granites is Gondwanan sediments derived from...
S-type granites always contain more Al than the amounts of Na, Ca and K in the rock required to form feldspars, primarily owing to their derivation from source components that had previously been weathered. Those rocks are therefore always saturated in Al, or peraluminous. Many I-type granites are also peraluminous, despite I-type source rocks typically not being saturated in Al. It has previously...
In the Ponte Segade area (Galicia, NW Spain) strongly differentiated granites, often associated with rare-element mineralization (Sn–Ta–Nb–Li–Be–Cs) that could be of economic interest, have recently been discovered. These granites appear in the northern sector of the Ollo de Sapo Antiform (Central Iberian Zone, Variscan Orogen). Three different muscovite-rich synkinematic and peraluminous types of...
The Pinilla de Fermoselle pegmatite is a cap-like body with an asymmetrical vertical zoning, from a granitic facies at the bottom to the upper contact with the metamorphic country-rocks. The granite grades imperceptibly into the pegmatite, which includes three main zones with different degrees of enrichment in Li+F+B (±P, Rb, Cs, Be, Sn). The essential minerals are quartz, feldspar, Al-micas from...
Crustal melting to produce granite magmas requires a tremendous amount of energy. In principle, there are three main mechanisms of heating that can extensively melt a fertile crust: radiogenic heat caused by the decay of 40 K, 230 Th, 235 U and 238 U; increased subcrustal heat flux caused by the upwelling of deeper, therefore hotter, mantle materials; advection of heat...
Major and trace-element microanalyses of the main minerals from the 610Ma Pedra Branca Syenite, southeast Brazil, allow inferences on intensive parameters of magmatic crystallization and on the partition of trace-elements among these minerals, with important implications for the petrogenetic evolution of the pluton. Two main syenite types make up the pluton, a quartz-free syenite with tabular alkali...
The Spanish Central System (SCS) is one of the largest granite batholiths in the European Variscan Belt. Zircons from five granitic intrusions from the eastern SCS have been separated and analysed for Hf isotopes by laser ablation MC-ICPMS, in order to evaluate the nature of granitic magma source. Two samples are cordierite-bearing S-type granites, the rest are amphibole-bearing I-type monzogranites...
Despite the consensus that TTGs, the main constituents of the Archaean continental crust worldwide, originated by partial melting of garnet-bearing amphibolites, natural evidence is scarce. A large variety of Archaean amphibole-rich rocks, including migmatitic amphibolites and hornblende-rich cumulates, was exhumed as a tectonic melange in the Inyoni shear zone (ISZ) near Barberton (South Africa),...
Crustal anatexis, coupled with melt extraction and ascent, is the main mechanism by which the continental crust differentiates. During diffusion-controlled melting, and in the absence of melt flow and mechanical mixing, diffusion is the main process by which the melt phase ultimately homogenizes and mineral residuum and melt equilibrate. Knowing the diffusive properties of the elements within a granitoid...
Magmas are commonly described through the usual content of 10 major oxides. This requires a complex dimensional plot. Concepts of hard–soft acid–base (HSAB) interactions allow estimating chemical reactivity of elements, such as electronegativity, i.e. the chemical potential changed of sign, hardness and electrophilicity. For complex system, those values result from equalization methods, i.e. the equalization...
Assimilation of foreign material into a granitic magma body entails mixing between two end-member components: the initially solid assimilant, and the original magma, whose composition is mostly represented by a granitic liquid. In this study, we assess the interactions between a haplogranite liquid made to the composition of the minimum at 200MPa H 2 O (Ab 38.23 Or 28.72 Qtz...
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