Chemical fluxes and wedge replenishment rates along recent destructive plate margins
In: Geology. Geological Society of America: Boulder. ISSN 0091-7613; e-ISSN 1943-2682, meer
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| Trefwoorden |
Chemical elements > Metals > Alkaline earth metals > Strontium
Chemistry > Geochemistry
Cycles > Chemical cycles
Earth sciences > Geology > Petrology
Earth structure > Earth crust > Continental crust
Earth structure > Earth mantle
Subduction zones
Topographic features > Submarine features > Continental margins
Marien/Kust |
| Auteurs | | Top |
- Hawkesworth, C.
- Ellam, R.
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| Abstract |
The Large Ion Lithophile Element (LILE) contents of island-are tholeiites are dominated by the contribution from the subducted slab, whereas those of continental margin rocks are dominated by that from the mantle wedge. It is therefore argued that the LILE abundances in the destructive-margin rocks that are most depleted in high field strength elements offer the best indication of the LILE flux from the subducted slab, and that the slab contributes similar to 25% of the Sr in average new crust. The remainder is derived from the mantle wedge, which is the principal site of crust generation and therefore must be replenished about every 75 m.y. |
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