The sources of island arcs as indicated by Nd and Sr isotopic studies
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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In the central Oregon Cascades, extension of the arc has promoted eruption of primitive basalts that are of three types, calcalkaline (CAB), low-K tholeiitic (LKT) and rare absarokitic (ABS) in the forearc. Based on a comparison with the distribution of primitive magma types and their Sr/Sr and Nd/Nd isotopic signature in the Cascades, we divide the arc into four segments that correspond to dis...
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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...
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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: Geophysical Research Letters
سال: 1977
ISSN: 0094-8276
DOI: 10.1029/gl004i010p00465