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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...
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