Izu-Bonin-Mariana Forearc

Figure 15 Chondrite-normalized abundances of REEs in abyssal peridotites from the East Pacific Rise and the Izu-Bonin-Mariana Forearc (whole-rock analyses). Data from Niu and Hekinian (1997a) and Godard (unpublished) for the East Pacific Rise, and from Parkinson and Pearce (1998) for the Izu-Bonin-Mariana Forearc.

Figure 17 Abundances of lithophile trace elements normalized to PM values in ophiolitic peridotites from Oman and Cuba, and in abyssal peridotites from the East Pacific Rise and the Izu-Bonin-Mariana Forearc (whole-rock analyses). Ophiolitic peridotites data from Godard et al. (2000) (reproduced by permission of Elsevier from Earth Planet. Set Lett. 2000,180, 133-148) for Oman, and from Proenza et al. (1999) for Cuba abyssal peridotites data from Niu and Hekinian (1997a) and Godard (unpublished) for the East Pacific Rise, and from Parkinson and Pearce (1998) for the Izu-Bonin-Mariana Forearc. Normalizing values after Sun and McDonough (1989).

The abyssal peridotites from the Izu-Bonin-Mariana Forearc resemble the ophiolitic peridotites. They are, nevertheless, distinguished by more prominent enrichments in alkaline and alkaline-earth elements (rubidium, caesium, strontium, and barium), possibly reflecting a supra-subduction imprint (Parkinson and Pearce, 1998). Except for one sample, they lack the niobium enrichment relative to FREE that is observed in the Ronda and... 

Parkinson 1. J. and Pearce J. A. (1998) Peridotites from the Izu-Bonin-Mariana Forearc (OOP Leg 125) evidence for mantle melting and melt-mantle interaction in a supra-subduction zone setting. J. Petrol. 39, 1577—1618. 

Mottl M. J. (1992) Pore waters from serpentine seamounts in the Mariana and Izu-Bonin Forearcs, Leg 125 evidence for volatiles from the subducting slab. Proc. ODP Sci. Results 125, 373-385. 

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