Titanium: A Tracer of Mafic Crust in Ocean Island Basalts?
Abstract
The recycling of mafic oceanic crust and its re-sampling in ocean island basalts (OIB) is a long-standing notion (e.g., 1). However, arguments based on trace element ratios and long-lived isotopic measurements fall prey to the uncertain make-up of the mantle source, time-integration and other added 'flavours' the OIB source may contain. Accordingly, the paradigm of crustal recycling continues to be debated (e.g., 2,3). With the advent of large online geochemical databases such as PetDB and GEOROC, major elements are yielding new insight to mantle melting processes. I review why the high field strength elements (HFSE) and titanium in particular appear to be a unique tracers of mafic oceanic crust in the source of ocean island basalts (e.g., 4). I will further explore the use of simple Ti abundances combined with other geochemical parameters in a well-characterised OIB suite from Pico, Azores to estimate the amount of recycled crust in the source. 1. Hofmann and White, 1982; 2. Niu and O'Hara, 2003; 3. Pilet et al. 2008; 4. Prytulak and Elliott, 2007
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2008
- Bibcode:
- 2008AGUFM.V31F..05P
- Keywords:
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- 1025 Composition of the mantle;
- 1065 Major and trace element geochemistry;
- 3619 Magma genesis and partial melting (1037);
- 3621 Mantle processes (1038)