Trace element composition of the middle Miocene basaltic rocks in Akita-Yamagata oil fields, northeastern Japan arc.
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چکیده
منابع مشابه
Pb, Nd, and Sr isotopic constraints on the origin of Miocene basaltic rocks from northeast Hokkaido, Japan: Implications for opening of the Kurile back-arc basin
Late Miocene (7–9 Ma) basaltic rocks from the Monbetsu-Kamishihoro graben in northeast Hokkaido have chemical affinities to certain back-arc basin basalts (referred to herein as Hokkaido BABB). Pb-, Ndand Sr-isotopic compositions of the Hokkaido BABB and arc-type volcanic rocks (11–13 Ma and 4–4.5 Ma) from the nearby region indicate mixing between the depleted mantle and an EM II-like enriched ...
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Trace element analysis of fossil bone and enamel constitutes a useful tool to characterize the paleoecological behavior of mammals. Up to now, most trace element studies have focused on Plio-Pleistocene fossils. Here, we show that paleodietary inferences based on trace element analyses can be also obtained from ~14Ma old Miocene mammals, in a period of time when important paleoclimatic changes ...
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Temporal variations in the orientation of Cenozoic range growth in northeastern Tibet defi ne two modes by which India-Asia convergence was accommodated. Thermochronological age-elevation transects from the hanging walls of two major thrust-fault systems reveal diachronous Miocene exhumation of the Laji-Jishi Shan in northeastern Tibet. Whereas accelerated growth of the WNW-trending eastern Laj...
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ژورنال
عنوان ژورنال: JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY
سال: 1988
ISSN: 0914-9783,1881-3275
DOI: 10.2465/ganko.83.486