High-Mg adakites from Kadavu Island Group, Fiji, southwest Pacific: Evidence for the mantle origin of adakite parental melts
نویسندگان
چکیده
منابع مشابه
Oxygen isotope evidence for slab melting in modern and ancient subduction zones
We measured oxygen isotope compositions of 34 adakites, high-Mg andesites, and lavas suspected to contain abundant slab and sediment melts from the Western and Central Aleutians, the Andes, Panama, Fiji, Kamchatka, Setouchi (Japan), and the Cascades. This suite covers much of the diversity of arc lavas previously hypothesized to contain abundant dslabT melts. Measured and calculated values of y...
متن کاملSlab melting in the Aleutians: implications of an ion probe study of clinopyroxene in primitive adakite and basalt
An ion probe study of trace elements in Mg-rich clinopyroxene phenocrysts in primitive Aleutian lavas provides constraints on the genesis of Aleutian adakites, and possible insights into the source of common Aleutian magmas. Clinopyroxene (cpx) phenocrysts in the primitive adakites have high Sr and Nd=Yb compared to cpx in Aleutian basalts. In the adakites, Sr and Nd=Yb are highest for high Mg#...
متن کاملEvidence from meimechites and other low-degree mantle melts for redox controls on mantle-crust fractionation of platinum-group elements.
Understanding of the geochemistry of the chalcophile elements [i.e., Os, Ir, Ru, Pt, Pd (platinum-group elements), and Au, Cu, Ni] has been informed for at least 20 years by the common assumption that when crust-forming partial melts are extracted from the upper mantle, sulfide liquid in the restite sequesters chalcophile elements until the extent of partial melting exceeds approximately 25% an...
متن کاملژئوشیمی رادیو ایزوتوپ‌های Rb–Sr و Sm–Nd و پتروژنز توده‌های نفوذی مرتبط با کانی‌سازی مس پورفیری غنی از طلای منطقه اکتشافی ماهرآباد (شمال هنیچ)، شرق ایران
The Maherabad gold-rich porphyry copper prospect area is located in the eastern part of Lut block, east of Iran. This is the first porphyry Cu-Au prospecting area which is discovered in eastern Iran. Fifteen mineralization-related intrusive rocks range (Middle Eocene 39 Ma) in composition from diorite to monzonite have been distinguished. Monzonitic porphyries had major role in Cu-Au mineraliza...
متن کاملAdakites from collision-modified lithosphere
[1] Adakitic melts from Papua New Guinea (PNG) show adakitic geochemical characteristics, yet their geodynamic context is unclear. Modern adakites are associated with hot-slab melting and/or remelting of orogenic mafic underplate at convergent margins. Rift-propagation over collision-modified lithosphere may explain the PNG adakite enigma, as PNG was influenced by rapid creation and subduction ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Geology
سال: 2008
ISSN: 0091-7613
DOI: 10.1130/g24349a.1