Time scales of intra-oceanic arc magmatism from combined U-Th and (U-Th)/He zircon geochronology of Dominica, Lesser Antilles
نویسندگان
چکیده
منابع مشابه
Laser microprobe (U–Th)/He geochronology
A new analytical method had been developed to enable high-spatial-resolution (U–Th)/He dating of accessory minerals. It involves the use of a focused ArF excimer to ablate pits in a polished grain surface, with the evolved gases spiked for isotope-dilution measurement of radiogenic He. These data are converted to concentrations by precise measurement of each pit using an optical interferometric...
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Seagrass beds are the largest organism-built marine habitat in Dominica, yet have only been surveyed since 2007. Standardized examinations along a depth gradient between 0 and 24 m, focusing on magnoliophyte species composition and benthic cover of shoots at 17 seagrass bed sites, were carried out between September 10 and December 7, 2008. The Cymodoceaceae Syringodium filiforme (Kuetzing 1860)...
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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...
متن کاملAdakite magmatism within the Sabzevar ophiolite zone, NE Iran: U-Pb geochronology and Sr-Nd isotopic evidences
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ژورنال
عنوان ژورنال: Geochemistry, Geophysics, Geosystems
سال: 2015
ISSN: 1525-2027
DOI: 10.1002/2014gc005636