Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and Cessation
Abstract The formerly continuous Vitiaz Arc broke into its Vanuatu and Fijian portions during a reversal of subduction polarity in the Miocene. Basaltic volcanism in Fiji that accompanied the breakup ranged from shoshonitic to low‐K and boninitic with increasing distance from the broken edge of the...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2022-12-01
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| Series: | Geochemistry, Geophysics, Geosystems |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2022GC010663 |
| _version_ | 1827771633745526784 |
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| author | James Gill Erin Todd Kaj Hoernle Folkmar Hauff Allison Ann Price Matthew G. Jackson |
| author_facet | James Gill Erin Todd Kaj Hoernle Folkmar Hauff Allison Ann Price Matthew G. Jackson |
| author_sort | James Gill |
| collection | DOAJ |
| description | Abstract The formerly continuous Vitiaz Arc broke into its Vanuatu and Fijian portions during a reversal of subduction polarity in the Miocene. Basaltic volcanism in Fiji that accompanied the breakup ranged from shoshonitic to low‐K and boninitic with increasing distance from the broken edge of the arc that, presumably, marks the broken edge of the slab. The Sr‐Pb‐Nd isotope ratios of the slab‐derived component in the breakup basalts most closely match those of the isotopically most depleted part of the Samoan seamount chain on the Pacific Plate that was adjacent to the site of breakup at 4–8 Ma, and differ from those of subsequent basalts in spreading segments of the surrounding backarc North Fiji and Lau Basins. Subduction of the Samoan Chain along the Vitiaz Trench Lineament may have controlled the limit of polarity reversal and, hence, where the double saloon doors (Martin, 2013) opened. Prior to breakup, Fijian volcanics were more similar isotopically to the Louisville Seamount Chain. |
| first_indexed | 2024-03-11T12:57:03Z |
| format | Article |
| id | doaj.art-e80206e64bbc4a2abe2155a5d2c15d24 |
| institution | Directory Open Access Journal |
| issn | 1525-2027 |
| language | English |
| last_indexed | 2024-03-11T12:57:03Z |
| publishDate | 2022-12-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geochemistry, Geophysics, Geosystems |
| spelling | doaj.art-e80206e64bbc4a2abe2155a5d2c15d242023-11-03T17:00:34ZengWileyGeochemistry, Geophysics, Geosystems1525-20272022-12-012312n/an/a10.1029/2022GC010663Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and CessationJames Gill0Erin Todd1Kaj Hoernle2Folkmar Hauff3Allison Ann Price4Matthew G. Jackson5Department of Earth and Planetary Sciences University of California Santa Cruz CA USAU.S. Geological Survey Alaska Science Center Anchorage AK USAGEOMAR Helmholtz Centre for Ocean Research Kiel GermanyGEOMAR Helmholtz Centre for Ocean Research Kiel GermanyDepartment of Earth Science University of California Santa Barbara CA USADepartment of Earth Science University of California Santa Barbara CA USAAbstract The formerly continuous Vitiaz Arc broke into its Vanuatu and Fijian portions during a reversal of subduction polarity in the Miocene. Basaltic volcanism in Fiji that accompanied the breakup ranged from shoshonitic to low‐K and boninitic with increasing distance from the broken edge of the arc that, presumably, marks the broken edge of the slab. The Sr‐Pb‐Nd isotope ratios of the slab‐derived component in the breakup basalts most closely match those of the isotopically most depleted part of the Samoan seamount chain on the Pacific Plate that was adjacent to the site of breakup at 4–8 Ma, and differ from those of subsequent basalts in spreading segments of the surrounding backarc North Fiji and Lau Basins. Subduction of the Samoan Chain along the Vitiaz Trench Lineament may have controlled the limit of polarity reversal and, hence, where the double saloon doors (Martin, 2013) opened. Prior to breakup, Fijian volcanics were more similar isotopically to the Louisville Seamount Chain.https://doi.org/10.1029/2022GC010663Fijisubduction reversalarc magmatismshoshoniteboniniteseamount chain |
| spellingShingle | James Gill Erin Todd Kaj Hoernle Folkmar Hauff Allison Ann Price Matthew G. Jackson Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and Cessation Geochemistry, Geophysics, Geosystems Fiji subduction reversal arc magmatism shoshonite boninite seamount chain |
| title | Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and Cessation |
| title_full | Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and Cessation |
| title_fullStr | Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and Cessation |
| title_full_unstemmed | Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and Cessation |
| title_short | Breaking Up Is Hard to Do: Magmatism During Oceanic Arc Breakup, Subduction Reversal, and Cessation |
| title_sort | breaking up is hard to do magmatism during oceanic arc breakup subduction reversal and cessation |
| topic | Fiji subduction reversal arc magmatism shoshonite boninite seamount chain |
| url | https://doi.org/10.1029/2022GC010663 |
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