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The northern margin of the Nagssugtoqidian mobile belt in Southeast Greenland exposes a suite of moderately fractionated Fe-rich tholeiitic dykes of Paleo-proterozoic age. The dykes were intruded during extension of the crust prior to the development of the Nagssugtoqidian mobile belt. Although the dykes recrystallized under amphibolite facies conditions during Proterozoic orogenesis, they suffered...
Carbonate rocks at the Bayan Obo giant rare earth element (REE)-Nb-Fe ore deposit, Inner Mongolia, China are divided into four categories: sedimentary limestone and dolostone (H8 s ), deformed mineralized coarse-grained dolomite marble (H8 c ) and fine-grained dolomite marble (H8 f ), and carbonatite dikes (D), based on their texture, mineral assemblage and geological occurrence...
Petrological, trace element and Sr, Nd, Pb isotopic data are reported for volcanic rocks from the island of Filicudi, Aeolian Arc, Southern Tyrrhenian Sea. The volcano consists of several monogenic and polygenic centres built up through four major phases of explosive and effusive activity started before 1 Ma. Rock composition ranges from calc-alkaline basalts to high-K andesites. There is a negative...
In the Iberian Massif, rocks of the K-rich plutonic series are not abundant, but towards internal parts of the belt represented by the Central Iberian Zone there are some sectors where shoshonitic plutonism occurs over broad areas. One of these areas is the anatectic Tormes Dome, encompassing two similar studied plutons (Pereruela and Vitigudino). A monzonitic association has been defined, ranging...
Petrological and geochemical data for a suite of mafic granulite xenoliths in Cenozoic alkali basalts from Saudi Arabia, Jordan and Syria provide a unique opportunity to explore the composition and nature of the lower crust beneath the Arabian Plate. Two mineralogically and chemically distinct groups of xenoliths occur. Group I is composed of two pyroxenes and plagioclase approximately in equal amounts...
In the Pulur complex, NE Turkey, a heterogeneous rock sequence ranging from quartz-rich mesocratic gneisses to silica- and alkali-deficient, Fe-, Mg- and Al-rich melanocratic rocks is characterized by granulite-facies assemblages involving garnet, cordierite, sillimanite, ilmenite, +/-spinel, +/-plagioclase, +/-quartz, +/-biotite, +/-corundum, rutile and monazite. Textural evidence for partial melting...
In the Carpathian-Pannonian region in Neogene times, westward-dipping subduction in a land-locked basin caused collision of two lithospheric blocks (Alcapa and Tisia) with the southeastern border of the European plate. Calc-alkaline and alkaline magmatism was closely related to subduction, rollback, collision and extension. From the spatial distribution of the magmatic activity, four segments can...
A quartz-monzodioritic dike associated with the porphyry-Cu mineralized stock at Santa Rita, NM, has been studied to constrain physico-chemical factors (P, T, f O2 , and volatile content) responsible for mineralization. The dike contains a low-variance mineral assemblage of amphibole, plagioclase (An 30-50 ), quartz, biotite, sphene, magnetite, and apatite,...
A model metasomatized lherzolite composition contains phlogopite and pargasite, together with olivine, orthopyroxene, clinopyroxene and spinel or garnet as subsolidus phases to 3 GPa. Previous works established that at >=1.5 GPa, phlogopite is stable above the dehydration solidus, determined by the melting behaviour of pargasite and coexisting phases. At 2.8 GPa, melts with residual phlogopite+garnet...
Central Anatolia exhibits good examples of calc-alkaline and alkaline magmatism of similar age in a collision-related tectonic setting (continent-island arc collision). In the Central Anatolia region, late Cretaceous post-collisional plutonic rocks intrude Palaeozoic-Mesozoic metamorphic rocks overthrust by Upper Cretaceous ophiolitic units to make up the Central Anatolian Crystalline Complex.In the...
The Iratsu body is the largest eclogitic body in the Sanbagawa belt, central Shikoku, composed of schists with pumpellyite-actinolite, through blueschist/greenschist transition and epidote-amphibolite, up to eclogite-facies grades. The Iratsu body and the underlying Higashi-Akaishi peridotite body are situated in the intermediate structural level of the Sanbagawa belt which occurs as a subhorizontal...
Pantelleria, the type locality of pantellerite, is a Late-Pleistocene magmatic system with a bimodal association of alkali basalts and peralkaline rocks showing a large compositional gap at SiO 2 =50-67 wt.%. Major and trace element data show a strong change in all element patterns with two distinct liquid lines of descent for the mafic and the felsic end-members for many elements (Al ...
The Paleoproterozoic Itapema Granite (IG) is a large granitic body that intrudes orthogneisses and amphibolites, altogether representing part of the basement for Neoproterozoic granitic magmatism in southern Brazil. It is composed of fine- to medium-grained hornblende-biotite monzogranites to granodiorites that host abundant country-rock xenoliths and irregularly distributed mafic aggregates. Interaction...
A careful examination of the geochemical data set for SE China granulite xenoliths in Cenozoic basalts shows differences between the magmatic and cumulate granulite xenoliths, but no distinction between the Nushan and the other South China magmatic granulite xenoliths. Nushan granulite xenoliths with Archean Nd model ages were most likely derived from the Archean basement of the Yangtze craton itself...
Many of the early Cretaceous intrusive complexes in the Damaraland of west-central Namibia are silicic in composition. Although all have trace element characteristics typical for the so-called A-type granites, major differences in alkali/aluminum ratios and isotopic compositions require diverse magma sources. This paper presents Nd and O isotope data from the five largest silicic complexes (Paresis,...
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