Classification of island arcs by Nd-Sr isotopic data.
نویسندگان
چکیده
منابع مشابه
THE SOURCES OF ISLAND ARCS AS INDICATED BY Nd AND Sr ISOTOPIC STUDIES
Abstmct: Island arc lavas from New Britain and the Marianas have 143 Nd/144 Nd similar to other oceanic basalts and distinctly different from continental flood basalts and thus appear to be derived from a high Sm/Nd, light-REE-depleted reservoir. Consideration of both Nd and Sr isotopes suggests seawater involvement in the generation of some island arc lavas and thus indicates that they may be ...
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salafchegan-khorhe volcanic rocks are exposed within urumieh-dokhtar magmatic belt. different kinds of volcanic and subvolcanic rocks of calc-alkaline to alkaline character have been reported throughout this magmatic belt. since, isotopic investigations are very useful for detection of magma petrogenesis and because no isotopic studies have been done in this area, so a geochemical and isotopic ...
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Samuel A. Bowring and Todd Housh (1) report Sm/Nd isotopic data giving a wide range of initial ENd values, from +3.5 to -4 at 4.0 billion years ago (Ga) and from +4 to -7 at 3.6 Ga. Their samples were from the Acasta gneisses of northern Canada, which represent the oldest known outcrops of continental crust (2). Their modeling of the Sm-Nd isotopic data is taken to suggest that the Acasta grani...
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Three intrusive granitoid bodies from northwest Saveh, central Iran, are embedded in volcanic sedimentary rocks of the Eocene,forming isolated small outcrops: Khalkhab quartz monzodioritic units (SiO2: ~52-57 wt %) to the northwest, Neshveh granodioriticunits (SiO2: ~62-71 wt %) to the northeast, and Selijerd granodioritic units (SiO2: ~63-69 wt %) to the southeast. The Khalkhab unit iscomposed...
متن کاملsr-nd isotopic characteristic, u-pb zircon geochronology, and petrogenesis of najmabad granodiorite batholith, eastern iran
the study area is located south of ghonabad in eastern iran. this area is situated between two major faults, darouneh to the north and dashtbyaz to the south. the movements of these faults cased major dislocation of this block. najmabad granodiorite to granite batholith is elongated trending east-west 2×8 km2. mineralization is associated with granite and monzonite. alteration zones are: propyl...
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ژورنال
عنوان ژورنال: GEOCHEMICAL JOURNAL
سال: 1984
ISSN: 0016-7002
DOI: 10.2343/geochemj.18.1