Abstract Arc magmatism is fundamental to the generation of new continental or island arc crust. However, mechanisms that add chemical complexity natural calc-alkaline magmas ranging from basaltic rhyolitic compositions are debated. Differentiation currently discussed include magma mixing, assimilation, crustal melting, (fractional) crystallisation. In this contribution, differentiation by decom...

Petrology and geochemical characteristics of granitic rocks from South Sulawesi, especially from Polewaliand Masamba area are presented in order to elucidate their origin of magma and geodynamic setting. The granitic rocks in these areas are dominated by granodiorite and granite in composition. Quartz, K-feldspar and plagioclase occur as major phases with hornblende and biotite as major ferroma...

Time-resolved geochemical data from the orthogneisses of basal units Allochthonous complexes NW Iberian Massif allow us to track changes in composition magmas generated a subduction-related setting that affects continental margin, which evolves building volcanic arc its dismantlement during rifting episode. The are interpreted as peripheral section North African margin Gondwana and record Neopr...

Charnockitic rocks form extensive orthogneiss plutons in many granulite terranes and are less commonly found in unmetamorphosed plutons, which have formed in various tectonic regimes. Geochemically, clearly igneous charnockites cover nearly the whole range of granite chemistry, from magnesian to ferroan and from calcic to alkalic. Pyroxenes from unmetamorphosed charnockitic rocks have compositi...

The Serra da Graciosa region includes important occurrences of granites and syenites of the Graciosa A-type Province (formerly Serra do Mar Suite), southern Brazil. Using fieldwork, petrography, and remote sensing imagery, we characterize the geology of the plutons in the region. Five individual plutons were recognized. Two correspond to the previously defined Marumbi and Anhangava Plutons. We ...

The Monte Santo Alkaline Intrusive Suite (MSAIS) is an association syenite foid, nepheline syenite and syenite. The MSAIS rocks are intruded in metapelites of the Rio do Coco meta-volcanic-sedimentary Sequence and are abundant pegmathoid veins cutting all of them. The mineral paragenesis is represented by aegirina, arfvedsonite, albite and nepheline, crystallized during the initial phase of cry...

Cratonic mantle eclogite xenoliths occur with diamond-bearing kimberlite. The modes and mineral compositions of eclogite contain important information on their origin, physical-chemical conditions of formation, and their geophysical properties. We have used the pseudosection option of the program PERPLEX to explore how mineral assemblage, abundance, and composition vary with bulk composition, t...