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TTGs and adakites: are they both slab melts?
Lithos, 2005Abstract Although both high-Al TTG (tonalite–trondhjemite–granodiorite) and adakite show strongly fractionated REE and incompatible element patterns, TTGs have lower Sr, Mg, Ni, Cr, and Nb/Ta than most adakites. These compositional differences cannot be easily related by shallow fractional crystallization. While adakites are probably slab melts, TTGs
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Adakites from Solander Island, New Zealand
New Zealand Journal of Geology and Geophysics, 1997Abstract The subduction related, island arc Pleistocene volcano of Solander Island in Foveaux Strait is composed of adakite, a new rock type first described from Adak Island in the Aleutian arc. Adakites are formed by the partial fusion of young oceanic crust under eclogitic facies conditions.
A. Reay, D. Parkinson
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Earth and Planetary Science Letters, 2008
Abstract Abundant dunite and harzbugite xenoliths are preserved in Early Cretaceous high-Mg# [63–67, where Mg# = molar 100 × Mg/(Mg + Fetot)] diorite intrusions from western Shandong in the North China Craton (NCC). Dunite and some harzburgite xenoliths typically preserve areas of orthopyroxenite (sometimes accompanied by phlogopite) either as veins ...
Wenliang Xu +5 more
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Abstract Abundant dunite and harzbugite xenoliths are preserved in Early Cretaceous high-Mg# [63–67, where Mg# = molar 100 × Mg/(Mg + Fetot)] diorite intrusions from western Shandong in the North China Craton (NCC). Dunite and some harzburgite xenoliths typically preserve areas of orthopyroxenite (sometimes accompanied by phlogopite) either as veins ...
Wenliang Xu +5 more
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Crustal thickness and adakite occurrence in the Philippines: Is there a relationship?
Island Arc, 2008AbstractAdakites are increasingly being recognized worldwide in a variety of tectonic settings. Models on the formation of this geochemically distinct class of volcanic rocks have evolved from partial melting of subducted young, hot oceanic slabs to magmatism resulting from oblique subduction, low‐angle or flat subduction, or even slab‐tearing.
Carla B. Dimalanta +1 more
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Adakitic magmas: modern analogues of Archaean granitoids
Lithos, 1999Both geochemical and experimental petrological research indicate that Archaean continental crust was generated by partial melting of an Archaean tholeiite transformed into a garnet-bearing amphibolite or eclogite. The geodynamic context of tholeiite melting is the subject of controversy.
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Island Arc, 2005
Abstract Small‐volume plutons of Early to Late Cretaceous ages are widely distributed in the Yamizo Mountains, central Japan. These plutons consist predominantly of granitoids, classified into hornblende gabbro, quartz diorite, hornblende–biotite granodiorite and coarse‐grained biotite granite.
Yutaka Takahashi +2 more
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Abstract Small‐volume plutons of Early to Late Cretaceous ages are widely distributed in the Yamizo Mountains, central Japan. These plutons consist predominantly of granitoids, classified into hornblende gabbro, quartz diorite, hornblende–biotite granodiorite and coarse‐grained biotite granite.
Yutaka Takahashi +2 more
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Adakites along oceanic transforms?
2003Quaternary dacites and trachytes from the Aird Hills and Lusancay Islands in Papua New Guinea show some of the clearest slab melt geochemical signatures (Mg# 73-93, Sr = 1520-2650 ppm, Sr/Y = 140-445, La/Yb = 135-238), yet there is no slab currently subducting beneath Papua New Guinea.
Haschke, M., Ben-Avraham, Z.
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Initiation of adakite occurrence in Cretaceous arc, Northeast Asia
Geosciences Journal, 2018Recent studies show that the Cretaceous intracontinental and arc tectonomagmatism in Northeast Asia resulted from the intracontinental mantle plume under the North China Craton and its channel-like flow that was dragged into the underneath of the ancient arc, respectively.
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Early paleozoic adakites in the eastern sayan: Geochemistry and sources
Geochemistry International, 2010The paper reports data on the geochemistry of Early Paleozoic granitoids in the Munku-Sardyk Range, Eastern Sayan. It has been established that the rocks composing this pluton have compositional characteristics corresponding to the genetically unified association of NEB (Nb-enriched basites) and adakites.
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