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Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Science / Faculty of Science >
Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy >
Vol.XXI, No.3 >
Major, Trace, and Rare Earth Element Abudances in Boninitic Lavas from the Ogasawara Forearc
| Title: | Major, Trace, and Rare Earth Element Abudances in Boninitic Lavas from the Ogasawara Forearc |
| Authors: | Johnson, Kevin T.M. Browse this author |
| Issue Date: | Aug-1985 |
| Publisher: | 北海道大学 |
| Journal Title: | 北海道大学理学部紀要 |
| Journal Title(alt): | Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy |
| Volume: | 21 |
| Issue: | 3 |
| Start Page: | 453 |
| End Page: | 463 |
| Abstract: | Dredged andesites and dacites from the Ogasawara forearc contain high abundances of MgO at high SiO2, high K2O, low rare earth element abundances and flat patterns, and very low TiO2 contents. The chemical character and geologic setting support the interpretation that these lavas are evolved members of the boninite series formed by high degrees of partial melting of a previously depleted arc source, followed by enrichment in K, Th, and large-ion lithophile elements, and finally differentiated to higher SiO2 contents than are usually found in boninites. This is consistent with existing tectonic models of the Izu-Mariana arc system in which young, hot Philippine Sea crust produced high geothermal gradients in this region from the Tertiary. |
| Type: | bulletin (article) |
| URI: | http://hdl.handle.net/2115/36738 |
| Appears in Collections: | Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy > Vol.XXI, No.3
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