| Autor: |
A. M. Morris, S. Lambart, M. A. Stearns, J. R. Bowman, M. T. Jones, G. Mohn, G. Andrews, J. Millett, C. Tegner, S. Chatterjee, J. Frieling, P. Guo, D. W. Jolley, E. H. Cunningham, C. Berndt, S. Planke, C. A. Alvarez Zarikian, P. Betlem, H. Brinkhuis, M. Christopoulou, E. Ferré, I. Y. Filina, D. T. Harper, J. Longman, R. P. Scherer, N. Varela, W. Xu, S. L. Yager, A. Agarwal, V. J. Clementi |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
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| Zdroj: |
Geochemistry, Geophysics, Geosystems, Vol 25, Iss 7, Pp n/a-n/a (2024) |
| Druh dokumentu: |
article |
| ISSN: |
1525-2027 |
| DOI: |
10.1029/2023GC011413 |
| Popis: |
Abstract While basaltic volcanism is dominant during rifting and continental breakup, felsic magmatism may be a significant component of some rift margins. During International Ocean Discovery Program (IODP) Expedition 396 on the continental margin of Norway, a graphite‐garnet‐cordierite bearing dacitic unit (the Mimir dacite) was recovered in two holes within early Eocene sediments on Mimir High (Site U1570), a marginal high on the Vøring Transform Margin. Here, we present a comprehensive textural, petrological, and geochemical study of the Mimir dacite in order to assess its origin and discuss the geodynamic implications. The major mineral phases (garnet, cordierite, quartz, plagioclase, alkali feldspar) are hosted in a fresh rhyolitic, vesicular, glassy matrix that is locally mingled with sediments. The major element chemistry of garnet and cordierite, the presence of zircon inclusions with inherited cores, and thermobarometric calculations all support an upper crustal metapelitic origin. While most magma‐rich margin models favor crustal anatexis in the lower crust, thermobarometric calculations performed here show that the Mimir dacite was produced at upper‐crustal depths ( |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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