Role of the subducted slab, mantle wedge and continental crust in the generation of adakites from the Andean Austral Volcanic Zone

  title={Role of the subducted slab, mantle wedge and continental crust in the generation of adakites from the Andean Austral Volcanic Zone},
  author={Charles R. Stern and R. Kilian},
  journal={Contributions to Mineralogy and Petrology},
Abstract All six Holocene volcanic centers of the Andean Austral Volcanic Zone (AVZ; 49–54°S) have erupted exclusively adakitic andesites and dacites characterized by low Yb and Y concentrations and high Sr/Y ratios, suggesting a source with residual garnet, amphibole and pyroxene, but little or no olivine and plagioclase. Melting of mafic lower crust may be the source for adakites in some arcs, but such a source is inconsistent with the high Mg# of AVZ adakites. Also, the AVZ occurs in a… Expand
Slab melting and slab melt metasomatism in the Northern Andean Volcanic Zone : adakites and high-Mg andesites from Pichincha volcano (Ecuador)
Situated in the fore-arc of the Northern Volcanic Zone (NVZ) of the Andes in Ecuador, Pichincha volcano is an active edifice where have been erupted unusual magmas as adakites and high-Mg andesites.Expand
Melting of a subducting oceanic crust from U–Th disequilibria in austral Andean lavas
Understanding crustal genesis at convergent plate boundaries is important for determining mass transfer between different geochemical reservoirs in the Earth's mantle, and for deciphering theExpand
Petrology and Geochemistry of Adakitic Dacites and High-MgO Andesites, and Related Calc-alkaline Dacites from the Miocene Okoppe Volcanic Field, N Hokkaido, Japan
In the Okoppe area of North Hokkaido, Japan, the eruption of adakitic and calc-alkaline dacites was followed by high-Mg andesite (HMA) and calc-alkaline dacite during the Middle Miocene (12–10 Ma).Expand
Adakitic rocks derived from the partial melting of subducted continental crust: Evidence from the Eocene volcanic rocks in the northern Qiangtang block
Abstract Eocene is a critical time for the elevation of Tibetan Plateau and global climate change, and previous studies suggested that the Eocene elevation was caused by intra-continental subductionExpand
The role of subduction erosion in the generation of Andean and other convergent plate boundary arc magmas, the continental crust and mantle
Abstract Subduction erosion, which occurs at all convergent plate boundaries associated with magmatic arcs formed on crystalline forearc basement, is an important process for chemical recycling,Expand
Petrological and geochemical constraints on the origin of adakites in the Garibaldi Volcanic Complex, southwestern British Columbia, Canada
The Garibaldi Volcanic Complex (GVC) is located in southwestern British Columbia and comprises two related but distinct volcanic fields: the Garibaldi Lake and the Mount Garibaldi volcanic fields.Expand
Magmatic evidence for Late Carboniferous-Early Permian slab breakoff and extension of the southern Mongolia collage system in Central Asia
Abstract Oceanic subduction and its last underthrusted part can both triggers arc-like magmatism. As the existence of multi-subduction zones in the Central Asian Orogenic Belt, controversy stillExpand
Geochemical modelling of early Eocene adakitic magmatism in the Eastern Pontides, NE Anatolia: continental crust or subducted oceanic slab origin?
Early Eocene adakitic volcanic and granitoid rocks are widespread in the Eastern Pontides of NE Turkey, providing significant constraints for the early Cenozoic tectonomagmatic evolution of theExpand
Triassic “adakitic” rocks in an extensional setting (North China): Melts from the cratonic lower crust
Abstract Adakite was originally defined as a specific type of magmatic rock derived from melting of subducted oceanic plates (Defant, M.J., Drummond, M.S., 1990. Derivation of some modern arc magmasExpand
Evidence from mantle xenoliths for relatively thin (<100 km) continental lithosphere below the Phanerozoic crust of southernmost South America
Garnet peridotite xenoliths in the Quaternary Pali-Aike alkali olivine basalts of southernmost South America are samples of the deeper portion of continental lithosphere formed by accretion along theExpand


Magnesian andesite in the western Aleutian Komandorsky region: Implications for slab melting and processes in the mantle wedge
The role of the subducting lithospheric slab in the genesis of mantle-derived (primitive) magmas is investigated through a study of volcanic rocks formed in the tectonically strike-slip–dominatedExpand
Derivation of some modern arc magmas by melting of young subducted lithosphere
MOST volcanic rocks in modern island and continental arcs are probably derived from melting of the mantle wedge, induced by hydrous fluids released during dehydration reactions in the subductedExpand
Isotope and Trace Element Data for Orogenic Andesites from the Austral Andes
The Austral Volcanic Zone of the Andes (AVZ, 49–55°S) consists of six Pleistocene to Recent volcanic centres resulting from the subduction of the Antarctic plate beneath southernmost South America.Expand
Aleutian magnesian andesites: Melts from subducted Pacific ocean crust
Abstract Several diagnostic chemical characteristics of an uncommon Aleutian magma type support a proposed origin that involves a small amount of partial melting of subducted Pacific ocean crustExpand
Mount St. Helens: Potential example of the partial melting of the subducted lithosphere in a volcanic arc
Mount St. Helens, 50 km to the west of Mount Adams and the main Cascade volcanic chain, is only 80 km above the subducting oceanic lithosphere. The elevated temperatures off the subducting slab,Expand
Volcanic Arc Magmas: Implications of a Melting-Mixing Model for Element Recycling in the Crust-Upper Mantle System
  • R. Kay
  • Geology
  • The Journal of Geology
  • 1980
A multicomponent melting-mixing model for the origin of volcanic arc basalt magmas implies signifi cant recycling of K, Rb, Ba, and other elements in the crust-upper mantel system. The model accountsExpand
Relative depletion of niobium in some arc magmas and the continental crust : partitioning of K, Nb, La, and Ce during melt/rock reaction in the upper mantle
Abstract Depletion of Nb relative to K and La is characteristic of lavas in subduction-related magmatic arcs, as distinct from mid-ocean ridge basalts. Nb depletion is also characteristic of theExpand
Isotopic composition of Late Jurassic and Early Cretaceous mafic igneous rocks from the southernmost Andes: impllcations for Sub-Andean mantle
ABSTRACT. A basaltic dike and minerals within a gabbro from the ophiolitic Tortuga Complex, a portion of the mafic floor of the Late Jurassic Rocas Verdes back-arc basin in southernmost SouthExpand
Partial melting of subducted oceanic crust and isolation of its residual eclogitic lithology
  • W. McDonough
  • Geology
  • Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences
  • 1991
Oceanic lithosphere is produced at mid-ocean ridges and reinjected into the mantle at convergent plate boundaries. During subduction, this lithosphere goes through a series of progressive dehydrationExpand
Petrochemistry and recrystallization history of granulite xenoliths from the Pali-Aike volcanic field, Chile
Mafic granulite facies xenoliths found in the Pleistocene-Recent alkali basalts of southern Patagonia, South America, have an unfoliated granoblastic matrix with the mineral assemblage clinopyroxeneExpand